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Diffstat (limited to 'tests/gpgscm/scheme.c')
| -rw-r--r-- | tests/gpgscm/scheme.c | 6043 |
1 files changed, 6043 insertions, 0 deletions
diff --git a/tests/gpgscm/scheme.c b/tests/gpgscm/scheme.c new file mode 100644 index 0000000..86d70b3 --- /dev/null +++ b/tests/gpgscm/scheme.c @@ -0,0 +1,6043 @@ +/* T I N Y S C H E M E 1 . 4 1 + * Dimitrios Souflis (dsouflis@acm.org) + * Based on MiniScheme (original credits follow) + * (MINISCM) coded by Atsushi Moriwaki (11/5/1989) + * (MINISCM) E-MAIL : moriwaki@kurims.kurims.kyoto-u.ac.jp + * (MINISCM) This version has been modified by R.C. Secrist. + * (MINISCM) + * (MINISCM) Mini-Scheme is now maintained by Akira KIDA. + * (MINISCM) + * (MINISCM) This is a revised and modified version by Akira KIDA. + * (MINISCM) current version is 0.85k4 (15 May 1994) + * + */ + +#ifdef HAVE_CONFIG_H +# include <config.h> +#endif + +#define _SCHEME_SOURCE +#include "scheme-private.h" +#ifndef WIN32 +# include <unistd.h> +#endif +#ifdef WIN32 +#define snprintf _snprintf +#endif +#if USE_DL +# include "dynload.h" +#endif +#if USE_MATH +# include <math.h> +#endif + +#include <assert.h> +#include <limits.h> +#include <stdint.h> +#include <float.h> +#include <ctype.h> + +#if USE_STRCASECMP +#include <strings.h> +# ifndef __APPLE__ +# define stricmp strcasecmp +# endif +#endif + +#include "gpgrt.h" /* For GGPRT_GCC_VERSION */ + +/* Used for documentation purposes, to signal functions in 'interface' */ +#define INTERFACE + +#define TOK_EOF (-1) +#define TOK_LPAREN 0 +#define TOK_RPAREN 1 +#define TOK_DOT 2 +#define TOK_ATOM 3 +#define TOK_QUOTE 4 +#define TOK_COMMENT 5 +#define TOK_DQUOTE 6 +#define TOK_BQUOTE 7 +#define TOK_COMMA 8 +#define TOK_ATMARK 9 +#define TOK_SHARP 10 +#define TOK_SHARP_CONST 11 +#define TOK_VEC 12 + +#define BACKQUOTE '`' +#define DELIMITERS "()\";\f\t\v\n\r " + +/* + * Basic memory allocation units + */ + +#define banner "TinyScheme 1.41" + +#include <string.h> +#include <stddef.h> +#include <stdlib.h> + +#ifdef __APPLE__ +static int stricmp(const char *s1, const char *s2) +{ + unsigned char c1, c2; + do { + c1 = tolower(*s1); + c2 = tolower(*s2); + if (c1 < c2) + return -1; + else if (c1 > c2) + return 1; + s1++, s2++; + } while (c1 != 0); + return 0; +} +#endif /* __APPLE__ */ + +#if USE_STRLWR && !defined(HAVE_STRLWR) +static const char *strlwr(char *s) { + const char *p=s; + while(*s) { + *s=tolower(*s); + s++; + } + return p; +} +#endif + +#ifndef prompt +# define prompt "ts> " +#endif + +#ifndef InitFile +# define InitFile "init.scm" +#endif + +#ifndef FIRST_CELLSEGS +# define FIRST_CELLSEGS 3 +#endif + + + +/* All types have the LSB set. The garbage collector takes advantage + * of that to identify types. */ +enum scheme_types { + T_STRING = 1 << 1 | 1, + T_NUMBER = 2 << 1 | 1, + T_SYMBOL = 3 << 1 | 1, + T_PROC = 4 << 1 | 1, + T_PAIR = 5 << 1 | 1, + T_CLOSURE = 6 << 1 | 1, + T_CONTINUATION = 7 << 1 | 1, + T_FOREIGN = 8 << 1 | 1, + T_CHARACTER = 9 << 1 | 1, + T_PORT = 10 << 1 | 1, + T_VECTOR = 11 << 1 | 1, + T_MACRO = 12 << 1 | 1, + T_PROMISE = 13 << 1 | 1, + T_ENVIRONMENT = 14 << 1 | 1, + T_FOREIGN_OBJECT = 15 << 1 | 1, + T_BOOLEAN = 16 << 1 | 1, + T_NIL = 17 << 1 | 1, + T_EOF_OBJ = 18 << 1 | 1, + T_SINK = 19 << 1 | 1, + T_FRAME = 20 << 1 | 1, + T_LAST_SYSTEM_TYPE = 20 << 1 | 1 +}; + +static const char * +type_to_string (enum scheme_types typ) +{ + switch (typ) + { + case T_STRING: return "string"; + case T_NUMBER: return "number"; + case T_SYMBOL: return "symbol"; + case T_PROC: return "proc"; + case T_PAIR: return "pair"; + case T_CLOSURE: return "closure"; + case T_CONTINUATION: return "continuation"; + case T_FOREIGN: return "foreign"; + case T_CHARACTER: return "character"; + case T_PORT: return "port"; + case T_VECTOR: return "vector"; + case T_MACRO: return "macro"; + case T_PROMISE: return "promise"; + case T_ENVIRONMENT: return "environment"; + case T_FOREIGN_OBJECT: return "foreign object"; + case T_BOOLEAN: return "boolean"; + case T_NIL: return "nil"; + case T_EOF_OBJ: return "eof object"; + case T_SINK: return "sink"; + case T_FRAME: return "frame"; + } + assert (! "not reached"); + return "?"; +} + +/* ADJ is enough slack to align cells in a TYPE_BITS-bit boundary */ +#define TYPE_BITS 6 +#define ADJ (1 << TYPE_BITS) +#define T_MASKTYPE (ADJ - 1) + /* 0000000000111111 */ +#define T_TAGGED 1024 /* 0000010000000000 */ +#define T_FINALIZE 2048 /* 0000100000000000 */ +#define T_SYNTAX 4096 /* 0001000000000000 */ +#define T_IMMUTABLE 8192 /* 0010000000000000 */ +#define T_ATOM 16384 /* 0100000000000000 */ /* only for gc */ +#define CLRATOM 49151 /* 1011111111111111 */ /* only for gc */ +#define MARK 32768 /* 1000000000000000 */ +#define UNMARK 32767 /* 0111111111111111 */ + + +static num num_add(num a, num b); +static num num_mul(num a, num b); +static num num_div(num a, num b); +static num num_intdiv(num a, num b); +static num num_sub(num a, num b); +static num num_rem(num a, num b); +static num num_mod(num a, num b); +static int num_eq(num a, num b); +static int num_gt(num a, num b); +static int num_ge(num a, num b); +static int num_lt(num a, num b); +static int num_le(num a, num b); + +#if USE_MATH +static double round_per_R5RS(double x); +#endif +static int is_zero_double(double x); +static INLINE int num_is_integer(pointer p) { + return ((p)->_object._number.is_fixnum); +} + +static const struct num num_zero = { 1, {0} }; +static const struct num num_one = { 1, {1} }; + +/* macros for cell operations */ +#define typeflag(p) ((p)->_flag) +#define type(p) (typeflag(p)&T_MASKTYPE) +#define settype(p, typ) (typeflag(p) = (typeflag(p) & ~T_MASKTYPE) | (typ)) + +INTERFACE INLINE int is_string(pointer p) { return (type(p)==T_STRING); } +#define strvalue(p) ((p)->_object._string._svalue) +#define strlength(p) ((p)->_object._string._length) + +INTERFACE static int is_list(scheme *sc, pointer p); +INTERFACE INLINE int is_vector(pointer p) { return (type(p)==T_VECTOR); } +/* Given a vector, return it's length. */ +#define vector_length(v) (v)->_object._vector._length +/* Given a vector length, compute the amount of cells required to + * represent it. */ +#define vector_size(len) (1 + ((len) - 1 + 2) / 3) +INTERFACE static void fill_vector(pointer vec, pointer obj); +INTERFACE static pointer *vector_elem_slot(pointer vec, int ielem); +INTERFACE static pointer vector_elem(pointer vec, int ielem); +INTERFACE static pointer set_vector_elem(pointer vec, int ielem, pointer a); +INTERFACE INLINE int is_number(pointer p) { return (type(p)==T_NUMBER); } +INTERFACE INLINE int is_integer(pointer p) { + if (!is_number(p)) + return 0; + if (num_is_integer(p) || (double)ivalue(p) == rvalue(p)) + return 1; + return 0; +} + +INTERFACE INLINE int is_real(pointer p) { + return is_number(p) && (!(p)->_object._number.is_fixnum); +} + +INTERFACE INLINE int is_character(pointer p) { return (type(p)==T_CHARACTER); } +INTERFACE INLINE char *string_value(pointer p) { return strvalue(p); } +INLINE num nvalue(pointer p) { return ((p)->_object._number); } +INTERFACE long ivalue(pointer p) { return (num_is_integer(p)?(p)->_object._number.value.ivalue:(long)(p)->_object._number.value.rvalue); } +INTERFACE double rvalue(pointer p) { return (!num_is_integer(p)?(p)->_object._number.value.rvalue:(double)(p)->_object._number.value.ivalue); } +#define ivalue_unchecked(p) ((p)->_object._number.value.ivalue) +#define rvalue_unchecked(p) ((p)->_object._number.value.rvalue) +#define set_num_integer(p) (p)->_object._number.is_fixnum=1; +#define set_num_real(p) (p)->_object._number.is_fixnum=0; +INTERFACE long charvalue(pointer p) { return ivalue_unchecked(p); } + +INTERFACE INLINE int is_port(pointer p) { return (type(p)==T_PORT); } +INTERFACE INLINE int is_inport(pointer p) { return is_port(p) && p->_object._port->kind & port_input; } +INTERFACE INLINE int is_outport(pointer p) { return is_port(p) && p->_object._port->kind & port_output; } + +INTERFACE INLINE int is_pair(pointer p) { return (type(p)==T_PAIR); } +#define car(p) ((p)->_object._cons._car) +#define cdr(p) ((p)->_object._cons._cdr) +INTERFACE pointer pair_car(pointer p) { return car(p); } +INTERFACE pointer pair_cdr(pointer p) { return cdr(p); } +INTERFACE pointer set_car(pointer p, pointer q) { return car(p)=q; } +INTERFACE pointer set_cdr(pointer p, pointer q) { return cdr(p)=q; } + +INTERFACE INLINE int is_symbol(pointer p) { return (type(p)==T_SYMBOL); } +INTERFACE INLINE char *symname(pointer p) { return strvalue(car(p)); } +#if USE_PLIST +SCHEME_EXPORT INLINE int hasprop(pointer p) { return (is_symbol(p)); } +#define symprop(p) cdr(p) +#endif + +INTERFACE INLINE int is_syntax(pointer p) { return (typeflag(p)&T_SYNTAX); } +INTERFACE INLINE int is_proc(pointer p) { return (type(p)==T_PROC); } +INTERFACE INLINE int is_foreign(pointer p) { return (type(p)==T_FOREIGN); } +INTERFACE INLINE char *syntaxname(pointer p) { return strvalue(car(p)); } +#define procnum(p) ivalue_unchecked(p) +static const char *procname(pointer x); + +INTERFACE INLINE int is_closure(pointer p) { return (type(p)==T_CLOSURE); } +INTERFACE INLINE int is_macro(pointer p) { return (type(p)==T_MACRO); } +INTERFACE INLINE pointer closure_code(pointer p) { return car(p); } +INTERFACE INLINE pointer closure_env(pointer p) { return cdr(p); } + +INTERFACE INLINE int is_continuation(pointer p) { return (type(p)==T_CONTINUATION); } +#define cont_dump(p) cdr(p) + +INTERFACE INLINE int is_foreign_object(pointer p) { return (type(p)==T_FOREIGN_OBJECT); } +INTERFACE const foreign_object_vtable *get_foreign_object_vtable(pointer p) { + return p->_object._foreign_object._vtable; +} +INTERFACE void *get_foreign_object_data(pointer p) { + return p->_object._foreign_object._data; +} + +/* To do: promise should be forced ONCE only */ +INTERFACE INLINE int is_promise(pointer p) { return (type(p)==T_PROMISE); } + +INTERFACE INLINE int is_environment(pointer p) { return (type(p)==T_ENVIRONMENT); } +#define setenvironment(p) typeflag(p) = T_ENVIRONMENT + +INTERFACE INLINE int is_frame(pointer p) { return (type(p) == T_FRAME); } +#define setframe(p) settype(p, T_FRAME) + +#define is_atom(p) (typeflag(p)&T_ATOM) +#define setatom(p) typeflag(p) |= T_ATOM +#define clratom(p) typeflag(p) &= CLRATOM + +#define is_mark(p) (typeflag(p)&MARK) +#define setmark(p) typeflag(p) |= MARK +#define clrmark(p) typeflag(p) &= UNMARK + +INTERFACE INLINE int is_immutable(pointer p) { return (typeflag(p)&T_IMMUTABLE); } +/*#define setimmutable(p) typeflag(p) |= T_IMMUTABLE*/ +INTERFACE INLINE void setimmutable(pointer p) { typeflag(p) |= T_IMMUTABLE; } + +#define caar(p) car(car(p)) +#define cadr(p) car(cdr(p)) +#define cdar(p) cdr(car(p)) +#define cddr(p) cdr(cdr(p)) +#define cadar(p) car(cdr(car(p))) +#define caddr(p) car(cdr(cdr(p))) +#define cdaar(p) cdr(car(car(p))) +#define cadaar(p) car(cdr(car(car(p)))) +#define cadddr(p) car(cdr(cdr(cdr(p)))) +#define cddddr(p) cdr(cdr(cdr(cdr(p)))) + +#if USE_HISTORY +static pointer history_flatten(scheme *sc); +static void history_mark(scheme *sc); +#else +# define history_mark(SC) (void) 0 +# define history_flatten(SC) (SC)->NIL +#endif + +#if USE_CHAR_CLASSIFIERS +static INLINE int Cisalpha(int c) { return isascii(c) && isalpha(c); } +static INLINE int Cisdigit(int c) { return isascii(c) && isdigit(c); } +static INLINE int Cisspace(int c) { return isascii(c) && isspace(c); } +static INLINE int Cisupper(int c) { return isascii(c) && isupper(c); } +static INLINE int Cislower(int c) { return isascii(c) && islower(c); } +#endif + +#if USE_ASCII_NAMES +static const char charnames[32][3]={ + "nul", + "soh", + "stx", + "etx", + "eot", + "enq", + "ack", + "bel", + "bs", + "ht", + "lf", + "vt", + "ff", + "cr", + "so", + "si", + "dle", + "dc1", + "dc2", + "dc3", + "dc4", + "nak", + "syn", + "etb", + "can", + "em", + "sub", + "esc", + "fs", + "gs", + "rs", + "us" +}; + +static int is_ascii_name(const char *name, int *pc) { + int i; + for(i=0; i<32; i++) { + if (strncasecmp(name, charnames[i], 3) == 0) { + *pc=i; + return 1; + } + } + if (strcasecmp(name, "del") == 0) { + *pc=127; + return 1; + } + return 0; +} + +#endif + +static int file_push(scheme *sc, pointer fname); +static void file_pop(scheme *sc); +static int file_interactive(scheme *sc); +static INLINE int is_one_of(char *s, int c); +static int alloc_cellseg(scheme *sc, int n); +static long binary_decode(const char *s); +static INLINE pointer get_cell(scheme *sc, pointer a, pointer b); +static pointer _get_cell(scheme *sc, pointer a, pointer b); +static pointer reserve_cells(scheme *sc, int n); +static pointer get_consecutive_cells(scheme *sc, int n); +static pointer find_consecutive_cells(scheme *sc, int n); +static int finalize_cell(scheme *sc, pointer a); +static int count_consecutive_cells(pointer x, int needed); +static pointer find_slot_in_env(scheme *sc, pointer env, pointer sym, int all); +static pointer mk_number(scheme *sc, num n); +static char *store_string(scheme *sc, int len, const char *str, char fill); +static pointer mk_vector(scheme *sc, int len); +static pointer mk_atom(scheme *sc, char *q); +static pointer mk_sharp_const(scheme *sc, char *name); +static pointer mk_port(scheme *sc, port *p); +static pointer port_from_filename(scheme *sc, const char *fn, int prop); +static pointer port_from_file(scheme *sc, FILE *, int prop); +static pointer port_from_string(scheme *sc, char *start, char *past_the_end, int prop); +static port *port_rep_from_filename(scheme *sc, const char *fn, int prop); +static port *port_rep_from_file(scheme *sc, FILE *, int prop); +static port *port_rep_from_string(scheme *sc, char *start, char *past_the_end, int prop); +static void port_close(scheme *sc, pointer p, int flag); +static void mark(pointer a); +static void gc(scheme *sc, pointer a, pointer b); +static int basic_inchar(port *pt); +static int inchar(scheme *sc); +static void backchar(scheme *sc, int c); +static char *readstr_upto(scheme *sc, char *delim); +static pointer readstrexp(scheme *sc); +static INLINE int skipspace(scheme *sc); +static int token(scheme *sc); +static void printslashstring(scheme *sc, char *s, int len); +static void atom2str(scheme *sc, pointer l, int f, char **pp, int *plen); +static void printatom(scheme *sc, pointer l, int f); +static pointer mk_proc(scheme *sc, enum scheme_opcodes op); +static pointer mk_closure(scheme *sc, pointer c, pointer e); +static pointer mk_continuation(scheme *sc, pointer d); +static pointer reverse(scheme *sc, pointer term, pointer list); +static pointer reverse_in_place(scheme *sc, pointer term, pointer list); +static pointer revappend(scheme *sc, pointer a, pointer b); +static void dump_stack_preallocate_frame(scheme *sc); +static void dump_stack_mark(scheme *); +struct op_code_info { + char name[31]; /* strlen ("call-with-current-continuation") + 1 */ + unsigned char min_arity; + unsigned char max_arity; + char arg_tests_encoding[3]; +}; +static const struct op_code_info dispatch_table[]; +static int check_arguments (scheme *sc, const struct op_code_info *pcd, char *msg, size_t msg_size); +static void Eval_Cycle(scheme *sc, enum scheme_opcodes op); +static void assign_syntax(scheme *sc, enum scheme_opcodes op, char *name); +static int syntaxnum(scheme *sc, pointer p); +static void assign_proc(scheme *sc, enum scheme_opcodes, const char *name); + +#define num_ivalue(n) (n.is_fixnum?(n).value.ivalue:(long)(n).value.rvalue) +#define num_rvalue(n) (!n.is_fixnum?(n).value.rvalue:(double)(n).value.ivalue) + +static num num_add(num a, num b) { + num ret; + ret.is_fixnum=a.is_fixnum && b.is_fixnum; + if(ret.is_fixnum) { + ret.value.ivalue= a.value.ivalue+b.value.ivalue; + } else { + ret.value.rvalue=num_rvalue(a)+num_rvalue(b); + } + return ret; +} + +static num num_mul(num a, num b) { + num ret; + ret.is_fixnum=a.is_fixnum && b.is_fixnum; + if(ret.is_fixnum) { + ret.value.ivalue= a.value.ivalue*b.value.ivalue; + } else { + ret.value.rvalue=num_rvalue(a)*num_rvalue(b); + } + return ret; +} + +static num num_div(num a, num b) { + num ret; + ret.is_fixnum=a.is_fixnum && b.is_fixnum && a.value.ivalue%b.value.ivalue==0; + if(ret.is_fixnum) { + ret.value.ivalue= a.value.ivalue/b.value.ivalue; + } else { + ret.value.rvalue=num_rvalue(a)/num_rvalue(b); + } + return ret; +} + +static num num_intdiv(num a, num b) { + num ret; + ret.is_fixnum=a.is_fixnum && b.is_fixnum; + if(ret.is_fixnum) { + ret.value.ivalue= a.value.ivalue/b.value.ivalue; + } else { + ret.value.rvalue=num_rvalue(a)/num_rvalue(b); + } + return ret; +} + +static num num_sub(num a, num b) { + num ret; + ret.is_fixnum=a.is_fixnum && b.is_fixnum; + if(ret.is_fixnum) { + ret.value.ivalue= a.value.ivalue-b.value.ivalue; + } else { + ret.value.rvalue=num_rvalue(a)-num_rvalue(b); + } + return ret; +} + +static num num_rem(num a, num b) { + num ret; + long e1, e2, res; + ret.is_fixnum=a.is_fixnum && b.is_fixnum; + e1=num_ivalue(a); + e2=num_ivalue(b); + res=e1%e2; + /* remainder should have same sign as second operand */ + if (res > 0) { + if (e1 < 0) { + res -= labs(e2); + } + } else if (res < 0) { + if (e1 > 0) { + res += labs(e2); + } + } + ret.value.ivalue=res; + return ret; +} + +static num num_mod(num a, num b) { + num ret; + long e1, e2, res; + ret.is_fixnum=a.is_fixnum && b.is_fixnum; + e1=num_ivalue(a); + e2=num_ivalue(b); + res=e1%e2; + /* modulo should have same sign as second operand */ + if (res * e2 < 0) { + res += e2; + } + ret.value.ivalue=res; + return ret; +} + +static int num_eq(num a, num b) { + int ret; + int is_fixnum=a.is_fixnum && b.is_fixnum; + if(is_fixnum) { + ret= a.value.ivalue==b.value.ivalue; + } else { + ret=num_rvalue(a)==num_rvalue(b); + } + return ret; +} + + +static int num_gt(num a, num b) { + int ret; + int is_fixnum=a.is_fixnum && b.is_fixnum; + if(is_fixnum) { + ret= a.value.ivalue>b.value.ivalue; + } else { + ret=num_rvalue(a)>num_rvalue(b); + } + return ret; +} + +static int num_ge(num a, num b) { + return !num_lt(a,b); +} + +static int num_lt(num a, num b) { + int ret; + int is_fixnum=a.is_fixnum && b.is_fixnum; + if(is_fixnum) { + ret= a.value.ivalue<b.value.ivalue; + } else { + ret=num_rvalue(a)<num_rvalue(b); + } + return ret; +} + +static int num_le(num a, num b) { + return !num_gt(a,b); +} + +#if USE_MATH +/* Round to nearest. Round to even if midway */ +static double round_per_R5RS(double x) { + double fl=floor(x); + double ce=ceil(x); + double dfl=x-fl; + double dce=ce-x; + if(dfl>dce) { + return ce; + } else if(dfl<dce) { + return fl; + } else { + if(fmod(fl,2.0)==0.0) { /* I imagine this holds */ + return fl; + } else { + return ce; + } + } +} +#endif + +static int is_zero_double(double x) { + return x<DBL_MIN && x>-DBL_MIN; +} + +static long binary_decode(const char *s) { + long x=0; + + while(*s!=0 && (*s=='1' || *s=='0')) { + x<<=1; + x+=*s-'0'; + s++; + } + + return x; +} + + + +/* + * Copying values. + * + * Occasionally, we need to copy a value from one location in the + * storage to another. Scheme objects are fine. Some primitive + * objects, however, require finalization, usually to free resources. + * + * For these values, we either make a copy or acquire a reference. + */ + +/* + * Copy SRC to DST. + * + * Copies the representation of SRC to DST. This makes SRC + * indistinguishable from DST from the perspective of a Scheme + * expression modulo the fact that they reside at a different location + * in the store. + * + * Conditions: + * + * - SRC must not be a vector. + * - Caller must ensure that any resources associated with the + * value currently stored in DST is accounted for. + */ +static void +copy_value(scheme *sc, pointer dst, pointer src) +{ + memcpy(dst, src, sizeof *src); + + /* We may need to make a copy or acquire a reference. */ + if (typeflag(dst) & T_FINALIZE) + switch (type(dst)) { + case T_STRING: + strvalue(dst) = store_string(sc, strlength(dst), strvalue(dst), 0); + break; + case T_PORT: + /* XXX acquire reference */ + assert (!"implemented"); + break; + case T_FOREIGN_OBJECT: + /* XXX acquire reference */ + assert (!"implemented"); + break; + case T_VECTOR: + assert (!"vectors cannot be copied"); + } +} + + + +/* Tags are like property lists, but can be attached to arbitrary + * values. */ + +static pointer +mk_tagged_value(scheme *sc, pointer v, pointer tag_car, pointer tag_cdr) +{ + pointer r, t; + + assert(! is_vector(v)); + + r = get_consecutive_cells(sc, 2); + if (r == sc->sink) + return sc->sink; + + copy_value(sc, r, v); + typeflag(r) |= T_TAGGED; + + t = r + 1; + typeflag(t) = T_PAIR; + car(t) = tag_car; + cdr(t) = tag_cdr; + + return r; +} + +static INLINE int +has_tag(pointer v) +{ + return !! (typeflag(v) & T_TAGGED); +} + +static INLINE pointer +get_tag(scheme *sc, pointer v) +{ + if (has_tag(v)) + return v + 1; + return sc->NIL; +} + + + +/* Low-level allocator. + * + * Memory is allocated in segments. Every segment holds a fixed + * number of cells. Segments are linked into a list, sorted in + * reverse address order (i.e. those with a higher address first). + * This is used in the garbage collector to build the freelist in + * address order. + */ + +struct cell_segment +{ + struct cell_segment *next; + void *alloc; + pointer cells; + size_t cells_len; +}; + +/* Allocate a new cell segment but do not make it available yet. */ +static int +_alloc_cellseg(scheme *sc, size_t len, struct cell_segment **segment) +{ + int adj = ADJ; + void *cp; + + if (adj < sizeof(struct cell)) + adj = sizeof(struct cell); + + /* The segment header is conveniently allocated with the cells. */ + cp = sc->malloc(sizeof **segment + len * sizeof(struct cell) + adj); + if (cp == NULL) + return 1; + + *segment = cp; + (*segment)->next = NULL; + (*segment)->alloc = cp; + cp = (void *) ((uintptr_t) cp + sizeof **segment); + + /* adjust in TYPE_BITS-bit boundary */ + if (((uintptr_t) cp) % adj != 0) + cp = (void *) (adj * ((uintptr_t) cp / adj + 1)); + + (*segment)->cells = cp; + (*segment)->cells_len = len; + return 0; +} + +/* Deallocate a cell segment. Returns the next cell segment. + * Convenient for deallocation in a loop. */ +static struct cell_segment * +_dealloc_cellseg(scheme *sc, struct cell_segment *segment) +{ + + struct cell_segment *next; + + if (segment == NULL) + return NULL; + + next = segment->next; + sc->free(segment->alloc); + return next; +} + +/* allocate new cell segment */ +static int alloc_cellseg(scheme *sc, int n) { + pointer last; + pointer p; + int k; + + for (k = 0; k < n; k++) { + struct cell_segment *new, **s; + if (_alloc_cellseg(sc, CELL_SEGSIZE, &new)) { + return k; + } + /* insert new segment in reverse address order */ + for (s = &sc->cell_segments; + *s && (uintptr_t) (*s)->alloc > (uintptr_t) new->alloc; + s = &(*s)->next) { + /* walk */ + } + new->next = *s; + *s = new; + + sc->fcells += new->cells_len; + last = new->cells + new->cells_len - 1; + for (p = new->cells; p <= last; p++) { + typeflag(p) = 0; + cdr(p) = p + 1; + car(p) = sc->NIL; + } + /* insert new cells in address order on free list */ + if (sc->free_cell == sc->NIL || p < sc->free_cell) { + cdr(last) = sc->free_cell; + sc->free_cell = new->cells; + } else { + p = sc->free_cell; + while (cdr(p) != sc->NIL && (uintptr_t) new->cells > (uintptr_t) cdr(p)) + p = cdr(p); + cdr(last) = cdr(p); + cdr(p) = new->cells; + } + } + return n; +} + + + +/* Controlling the garbage collector. + * + * Every time a cell is allocated, the interpreter may run out of free + * cells and do a garbage collection. This is problematic because it + * might garbage collect objects that have been allocated, but are not + * yet made available to the interpreter. + * + * Previously, we would plug such newly allocated cells into the list + * of newly allocated objects rooted at car(sc->sink), but that + * requires allocating yet another cell increasing pressure on the + * memory management system. + * + * A faster alternative is to preallocate the cells needed for an + * operation and make sure the garbage collection is not run until all + * allocated objects are plugged in. This can be done with gc_disable + * and gc_enable. + */ + +/* The garbage collector is enabled if the inhibit counter is + * zero. */ +#define GC_ENABLED 0 + +/* For now we provide a way to disable this optimization for + * benchmarking and because it produces slightly smaller code. */ +#ifndef USE_GC_LOCKING +# define USE_GC_LOCKING 1 +#endif + +/* To facilitate nested calls to gc_disable, functions that allocate + * more than one cell may define a macro, e.g. foo_allocates. This + * macro can be used to compute the amount of preallocation at the + * call site with the help of this macro. */ +#define gc_reservations(fn) fn ## _allocates + +#if USE_GC_LOCKING + +/* Report a shortage in reserved cells, and terminate the program. */ +static void +gc_reservation_failure(struct scheme *sc) +{ +#ifdef NDEBUG + fprintf(stderr, + "insufficient reservation\n"); +#else + fprintf(stderr, + "insufficient %s reservation in line %d\n", + sc->frame_freelist == sc->NIL ? "frame" : "cell", + sc->reserved_lineno); +#endif + abort(); +} + +/* Disable the garbage collection and reserve the given number of + * cells. gc_disable may be nested, but the enclosing reservation + * must include the reservations of all nested calls. Note: You must + * re-enable the gc before calling Error_X. */ +static void +_gc_disable(struct scheme *sc, size_t reserve, int lineno) +{ + if (sc->inhibit_gc == 0) { + reserve_cells(sc, (reserve)); + sc->reserved_cells = (reserve); +#ifdef NDEBUG + (void) lineno; +#else + sc->reserved_lineno = lineno; +#endif + } else if (sc->reserved_cells < (reserve)) + gc_reservation_failure (sc); + sc->inhibit_gc += 1; +} +#define gc_disable(sc, reserve) \ + do { \ + if (sc->frame_freelist == sc->NIL) { \ + if (gc_enabled(sc)) \ + dump_stack_preallocate_frame(sc); \ + else \ + gc_reservation_failure(sc); \ + } \ + _gc_disable (sc, reserve, __LINE__); \ + } while (0) + +/* Enable the garbage collector. */ +#define gc_enable(sc) \ + do { \ + assert(sc->inhibit_gc); \ + sc->inhibit_gc -= 1; \ + } while (0) + +/* Test whether the garbage collector is enabled. */ +#define gc_enabled(sc) \ + (sc->inhibit_gc == GC_ENABLED) + +/* Consume a reserved cell. */ +#define gc_consume(sc) \ + do { \ + assert(! gc_enabled (sc)); \ + if (sc->reserved_cells == 0) \ + gc_reservation_failure (sc); \ + sc->reserved_cells -= 1; \ + } while (0) + +#else /* USE_GC_LOCKING */ + +#define gc_reservation_failure(sc) (void) 0 +#define gc_disable(sc, reserve) \ + do { \ + if (sc->frame_freelist == sc->NIL) \ + dump_stack_preallocate_frame(sc); \ + } while (0) +#define gc_enable(sc) (void) 0 +#define gc_enabled(sc) 1 +#define gc_consume(sc) (void) 0 + +#endif /* USE_GC_LOCKING */ + +static INLINE pointer get_cell_x(scheme *sc, pointer a, pointer b) { + if (! gc_enabled (sc) || sc->free_cell != sc->NIL) { + pointer x = sc->free_cell; + if (! gc_enabled (sc)) + gc_consume (sc); + sc->free_cell = cdr(x); + --sc->fcells; + return (x); + } + assert (gc_enabled (sc)); + return _get_cell (sc, a, b); +} + + +/* get new cell. parameter a, b is marked by gc. */ +static pointer _get_cell(scheme *sc, pointer a, pointer b) { + pointer x; + + if(sc->no_memory) { + return sc->sink; + } + + assert (gc_enabled (sc)); + if (sc->free_cell == sc->NIL) { + gc(sc,a, b); + if (sc->free_cell == sc->NIL) { + sc->no_memory=1; + return sc->sink; + } + } + x = sc->free_cell; + sc->free_cell = cdr(x); + --sc->fcells; + return (x); +} + +/* make sure that there is a given number of cells free */ +static pointer reserve_cells(scheme *sc, int n) { + if(sc->no_memory) { + return sc->NIL; + } + + /* Are there enough cells available? */ + if (sc->fcells < n) { + /* If not, try gc'ing some */ + gc(sc, sc->NIL, sc->NIL); + if (sc->fcells < n) { + /* If there still aren't, try getting more heap */ + if (!alloc_cellseg(sc,1)) { + sc->no_memory=1; + return sc->NIL; + } + } + if (sc->fcells < n) { + /* If all fail, report failure */ + sc->no_memory=1; + return sc->NIL; + } + } + return (sc->T); +} + +static pointer get_consecutive_cells(scheme *sc, int n) { + pointer x; + + if(sc->no_memory) { return sc->sink; } + + /* Are there any cells available? */ + x=find_consecutive_cells(sc,n); + if (x != sc->NIL) { return x; } + + /* If not, try gc'ing some */ + gc(sc, sc->NIL, sc->NIL); + x=find_consecutive_cells(sc,n); + if (x != sc->NIL) { return x; } + + /* If there still aren't, try getting more heap */ + if (!alloc_cellseg(sc,1)) + { + sc->no_memory=1; + return sc->sink; + } + + x=find_consecutive_cells(sc,n); + if (x != sc->NIL) { return x; } + + /* If all fail, report failure */ + sc->no_memory=1; + return sc->sink; +} + +static int count_consecutive_cells(pointer x, int needed) { + int n=1; + while(cdr(x)==x+1) { + x=cdr(x); + n++; + if(n>needed) return n; + } + return n; +} + +static pointer find_consecutive_cells(scheme *sc, int n) { + pointer *pp; + int cnt; + + pp=&sc->free_cell; + while(*pp!=sc->NIL) { + cnt=count_consecutive_cells(*pp,n); + if(cnt>=n) { + pointer x=*pp; + *pp=cdr(*pp+n-1); + sc->fcells -= n; + return x; + } + pp=&cdr(*pp+cnt-1); + } + return sc->NIL; +} + +/* Free a cell. This is dangerous. Only free cells that are not + * referenced. */ +static INLINE void +free_cell(scheme *sc, pointer a) +{ + cdr(a) = sc->free_cell; + sc->free_cell = a; + sc->fcells += 1; +} + +/* Free a cell and retrieve its content. This is dangerous. Only + * free cells that are not referenced. */ +static INLINE void +free_cons(scheme *sc, pointer a, pointer *r_car, pointer *r_cdr) +{ + *r_car = car(a); + *r_cdr = cdr(a); + free_cell(sc, a); +} + +/* To retain recent allocs before interpreter knows about them - + Tehom */ + +static void push_recent_alloc(scheme *sc, pointer recent, pointer extra) +{ + pointer holder = get_cell_x(sc, recent, extra); + typeflag(holder) = T_PAIR | T_IMMUTABLE; + car(holder) = recent; + cdr(holder) = car(sc->sink); + car(sc->sink) = holder; +} + +static INLINE void ok_to_freely_gc(scheme *sc) +{ + pointer a = car(sc->sink), next; + car(sc->sink) = sc->NIL; + while (a != sc->NIL) + { + next = cdr(a); + free_cell(sc, a); + a = next; + } +} + +static pointer get_cell(scheme *sc, pointer a, pointer b) +{ + pointer cell = get_cell_x(sc, a, b); + /* For right now, include "a" and "b" in "cell" so that gc doesn't + think they are garbage. */ + /* Tentatively record it as a pair so gc understands it. */ + typeflag(cell) = T_PAIR; + car(cell) = a; + cdr(cell) = b; + if (gc_enabled (sc)) + push_recent_alloc(sc, cell, sc->NIL); + return cell; +} + +static pointer get_vector_object(scheme *sc, int len, pointer init) +{ + pointer cells = get_consecutive_cells(sc, vector_size(len)); + int i; + int alloc_len = 1 + 3 * (vector_size(len) - 1); + if(sc->no_memory) { return sc->sink; } + /* Record it as a vector so that gc understands it. */ + typeflag(cells) = (T_VECTOR | T_ATOM | T_FINALIZE); + vector_length(cells) = len; + fill_vector(cells,init); + + /* Initialize the unused slots at the end. */ + assert (alloc_len - len < 3); + for (i = len; i < alloc_len; i++) + cells->_object._vector._elements[i] = sc->NIL; + + if (gc_enabled (sc)) + push_recent_alloc(sc, cells, sc->NIL); + return cells; +} + +/* Medium level cell allocation */ + +/* get new cons cell */ +pointer _cons(scheme *sc, pointer a, pointer b, int immutable) { + pointer x = get_cell(sc,a, b); + + typeflag(x) = T_PAIR; + if(immutable) { + setimmutable(x); + } + car(x) = a; + cdr(x) = b; + return (x); +} + + +/* ========== oblist implementation ========== */ + +#ifndef USE_OBJECT_LIST + +static int hash_fn(const char *key, int table_size); + +static pointer oblist_initial_value(scheme *sc) +{ + /* There are about 768 symbols used after loading the + * interpreter. */ + return mk_vector(sc, 1009); +} + +/* Lookup the symbol NAME. Returns the symbol, or NIL if it does not + * exist. In that case, SLOT points to the point where the new symbol + * is to be inserted. */ +static INLINE pointer +oblist_find_by_name(scheme *sc, const char *name, pointer **slot) +{ + int location; + pointer x; + char *s; + int d; + + location = hash_fn(name, vector_length(sc->oblist)); + for (*slot = vector_elem_slot(sc->oblist, location), x = **slot; + x != sc->NIL; *slot = &cdr(x), x = **slot) { + s = symname(car(x)); + /* case-insensitive, per R5RS section 2. */ + d = stricmp(name, s); + if (d == 0) + return car(x); /* Hit. */ + else if (d > 0) + break; /* Miss. */ + } + return sc->NIL; +} + +static pointer oblist_all_symbols(scheme *sc) +{ + int i; + pointer x; + pointer ob_list = sc->NIL; + + for (i = 0; i < vector_length(sc->oblist); i++) { + for (x = vector_elem(sc->oblist, i); x != sc->NIL; x = cdr(x)) { + ob_list = cons(sc, x, ob_list); + } + } + return ob_list; +} + +#else + +static pointer oblist_initial_value(scheme *sc) +{ + return sc->NIL; +} + +/* Lookup the symbol NAME. Returns the symbol, or NIL if it does not + * exist. In that case, SLOT points to the point where the new symbol + * is to be inserted. */ +static INLINE pointer +oblist_find_by_name(scheme *sc, const char *name, pointer **slot) +{ + pointer x; + char *s; + int d; + + for (*slot = &sc->oblist, x = **slot; x != sc->NIL; *slot = &cdr(x), x = **slot) { + s = symname(car(x)); + /* case-insensitive, per R5RS section 2. */ + d = stricmp(name, s); + if (d == 0) + return car(x); /* Hit. */ + else if (d > 0) + break; /* Miss. */ + } + return sc->NIL; +} + +static pointer oblist_all_symbols(scheme *sc) +{ + return sc->oblist; +} + +#endif + +/* Add a new symbol NAME at SLOT. SLOT must be obtained using + * oblist_find_by_name, and no insertion must be done between + * obtaining the SLOT and calling this function. Returns the new + * symbol. */ +static pointer oblist_add_by_name(scheme *sc, const char *name, pointer *slot) +{ +#define oblist_add_by_name_allocates 3 + pointer x; + + gc_disable(sc, gc_reservations (oblist_add_by_name)); + x = immutable_cons(sc, mk_string(sc, name), sc->NIL); + typeflag(x) = T_SYMBOL; + setimmutable(car(x)); + *slot = immutable_cons(sc, x, *slot); + gc_enable(sc); + return x; +} + + + +static pointer mk_port(scheme *sc, port *p) { + pointer x = get_cell(sc, sc->NIL, sc->NIL); + + typeflag(x) = T_PORT|T_ATOM|T_FINALIZE; + x->_object._port=p; + return (x); +} + +pointer mk_foreign_func(scheme *sc, foreign_func f) { + pointer x = get_cell(sc, sc->NIL, sc->NIL); + + typeflag(x) = (T_FOREIGN | T_ATOM); + x->_object._ff=f; + return (x); +} + +pointer mk_foreign_object(scheme *sc, const foreign_object_vtable *vtable, void *data) { + pointer x = get_cell(sc, sc->NIL, sc->NIL); + + typeflag(x) = (T_FOREIGN_OBJECT | T_ATOM | T_FINALIZE); + x->_object._foreign_object._vtable=vtable; + x->_object._foreign_object._data = data; + return (x); +} + +INTERFACE pointer mk_character(scheme *sc, int c) { + pointer x = get_cell(sc,sc->NIL, sc->NIL); + + typeflag(x) = (T_CHARACTER | T_ATOM); + ivalue_unchecked(x)= c; + set_num_integer(x); + return (x); +} + + + +#if USE_SMALL_INTEGERS + +static const struct cell small_integers[] = { +#define DEFINE_INTEGER(n) { T_NUMBER | T_ATOM | MARK, {{ 1, {n}}}}, +#include "small-integers.h" +#undef DEFINE_INTEGER + {0} +}; + +#define MAX_SMALL_INTEGER (sizeof small_integers / sizeof *small_integers - 1) + +static INLINE pointer +mk_small_integer(scheme *sc, long n) +{ +#define mk_small_integer_allocates 0 + (void) sc; + assert(0 <= n && n < MAX_SMALL_INTEGER); + return (pointer) &small_integers[n]; +} +#else + +#define mk_small_integer_allocates 1 +#define mk_small_integer mk_integer + +#endif + +/* get number atom (integer) */ +INTERFACE pointer mk_integer(scheme *sc, long n) { + pointer x; + +#if USE_SMALL_INTEGERS + if (0 <= n && n < MAX_SMALL_INTEGER) + return mk_small_integer(sc, n); +#endif + + x = get_cell(sc,sc->NIL, sc->NIL); + typeflag(x) = (T_NUMBER | T_ATOM); + ivalue_unchecked(x)= n; + set_num_integer(x); + return (x); +} + + + +INTERFACE pointer mk_real(scheme *sc, double n) { + pointer x = get_cell(sc,sc->NIL, sc->NIL); + + typeflag(x) = (T_NUMBER | T_ATOM); + rvalue_unchecked(x)= n; + set_num_real(x); + return (x); +} + +static pointer mk_number(scheme *sc, num n) { + if(n.is_fixnum) { + return mk_integer(sc,n.value.ivalue); + } else { + return mk_real(sc,n.value.rvalue); + } +} + +/* allocate name to string area */ +static char *store_string(scheme *sc, int len_str, const char *str, char fill) { + char *q; + + q=(char*)sc->malloc(len_str+1); + if(q==0) { + sc->no_memory=1; + return sc->strbuff; + } + if(str!=0) { + memcpy (q, str, len_str); + q[len_str]=0; + } else { + memset(q, fill, len_str); + q[len_str]=0; + } + return (q); +} + +/* get new string */ +INTERFACE pointer mk_string(scheme *sc, const char *str) { + return mk_counted_string(sc,str,strlen(str)); +} + +INTERFACE pointer mk_counted_string(scheme *sc, const char *str, int len) { + pointer x = get_cell(sc, sc->NIL, sc->NIL); + typeflag(x) = (T_STRING | T_ATOM | T_FINALIZE); + strvalue(x) = store_string(sc,len,str,0); + strlength(x) = len; + return (x); +} + +INTERFACE pointer mk_empty_string(scheme *sc, int len, char fill) { + pointer x = get_cell(sc, sc->NIL, sc->NIL); + typeflag(x) = (T_STRING | T_ATOM | T_FINALIZE); + strvalue(x) = store_string(sc,len,0,fill); + strlength(x) = len; + return (x); +} + +INTERFACE static pointer mk_vector(scheme *sc, int len) +{ return get_vector_object(sc,len,sc->NIL); } + +INTERFACE static void fill_vector(pointer vec, pointer obj) { + size_t i; + assert (is_vector (vec)); + for(i = 0; i < vector_length(vec); i++) { + vec->_object._vector._elements[i] = obj; + } +} + +INTERFACE static pointer *vector_elem_slot(pointer vec, int ielem) { + assert (is_vector (vec)); + assert (ielem < vector_length(vec)); + return &vec->_object._vector._elements[ielem]; +} + +INTERFACE static pointer vector_elem(pointer vec, int ielem) { + assert (is_vector (vec)); + assert (ielem < vector_length(vec)); + return vec->_object._vector._elements[ielem]; +} + +INTERFACE static pointer set_vector_elem(pointer vec, int ielem, pointer a) { + assert (is_vector (vec)); + assert (ielem < vector_length(vec)); + vec->_object._vector._elements[ielem] = a; + return a; +} + +/* get new symbol */ +INTERFACE pointer mk_symbol(scheme *sc, const char *name) { +#define mk_symbol_allocates oblist_add_by_name_allocates + pointer x; + pointer *slot; + + /* first check oblist */ + x = oblist_find_by_name(sc, name, &slot); + if (x != sc->NIL) { + return (x); + } else { + x = oblist_add_by_name(sc, name, slot); + return (x); + } +} + +INTERFACE pointer gensym(scheme *sc) { + pointer x; + pointer *slot; + char name[40]; + + for(; sc->gensym_cnt<LONG_MAX; sc->gensym_cnt++) { + snprintf(name,40,"gensym-%ld",sc->gensym_cnt); + + /* first check oblist */ + x = oblist_find_by_name(sc, name, &slot); + + if (x != sc->NIL) { + continue; + } else { + x = oblist_add_by_name(sc, name, slot); + return (x); + } + } + + return sc->NIL; +} + +/* double the size of the string buffer */ +static int expand_strbuff(scheme *sc) { + size_t new_size = sc->strbuff_size * 2; + char *new_buffer = sc->malloc(new_size); + if (new_buffer == 0) { + sc->no_memory = 1; + return 1; + } + memcpy(new_buffer, sc->strbuff, sc->strbuff_size); + sc->free(sc->strbuff); + sc->strbuff = new_buffer; + sc->strbuff_size = new_size; + return 0; +} + +/* make symbol or number atom from string */ +static pointer mk_atom(scheme *sc, char *q) { + char c, *p; + int has_dec_point=0; + int has_fp_exp = 0; + +#if USE_COLON_HOOK + char *next; + next = p = q; + while ((next = strstr(next, "::")) != 0) { + /* Keep looking for the last occurrence. */ + p = next; + next = next + 2; + } + + if (p != q) { + *p=0; + return cons(sc, sc->COLON_HOOK, + cons(sc, + cons(sc, + sc->QUOTE, + cons(sc, mk_symbol(sc, strlwr(p + 2)), + sc->NIL)), + cons(sc, mk_atom(sc, q), sc->NIL))); + } +#endif + + p = q; + c = *p++; + if ((c == '+') || (c == '-')) { + c = *p++; + if (c == '.') { + has_dec_point=1; + c = *p++; + } + if (!isdigit(c)) { + return (mk_symbol(sc, strlwr(q))); + } + } else if (c == '.') { + has_dec_point=1; + c = *p++; + if (!isdigit(c)) { + return (mk_symbol(sc, strlwr(q))); + } + } else if (!isdigit(c)) { + return (mk_symbol(sc, strlwr(q))); + } + + for ( ; (c = *p) != 0; ++p) { + if (!isdigit(c)) { + if(c=='.') { + if(!has_dec_point) { + has_dec_point=1; + continue; + } + } + else if ((c == 'e') || (c == 'E')) { + if(!has_fp_exp) { + has_dec_point = 1; /* decimal point illegal + from now on */ + p++; + if ((*p == '-') || (*p == '+') || isdigit(*p)) { + continue; + } + } + } + return (mk_symbol(sc, strlwr(q))); + } + } + if(has_dec_point) { + return mk_real(sc,atof(q)); + } + return (mk_integer(sc, atol(q))); +} + +/* make constant */ +static pointer mk_sharp_const(scheme *sc, char *name) { + long x; + char tmp[STRBUFFSIZE]; + + if (!strcmp(name, "t")) + return (sc->T); + else if (!strcmp(name, "f")) + return (sc->F); + else if (*name == 'o') {/* #o (octal) */ + snprintf(tmp, STRBUFFSIZE, "0%s", name+1); + sscanf(tmp, "%lo", (long unsigned *)&x); + return (mk_integer(sc, x)); + } else if (*name == 'd') { /* #d (decimal) */ + sscanf(name+1, "%ld", (long int *)&x); + return (mk_integer(sc, x)); + } else if (*name == 'x') { /* #x (hex) */ + snprintf(tmp, STRBUFFSIZE, "0x%s", name+1); + sscanf(tmp, "%lx", (long unsigned *)&x); + return (mk_integer(sc, x)); + } else if (*name == 'b') { /* #b (binary) */ + x = binary_decode(name+1); + return (mk_integer(sc, x)); + } else if (*name == '\\') { /* #\w (character) */ + int c=0; + if(stricmp(name+1,"space")==0) { + c=' '; + } else if(stricmp(name+1,"newline")==0) { + c='\n'; + } else if(stricmp(name+1,"return")==0) { + c='\r'; + } else if(stricmp(name+1,"tab")==0) { + c='\t'; + } else if(name[1]=='x' && name[2]!=0) { + int c1=0; + if(sscanf(name+2,"%x",(unsigned int *)&c1)==1 && c1 < UCHAR_MAX) { + c=c1; + } else { + return sc->NIL; + } +#if USE_ASCII_NAMES + } else if(is_ascii_name(name+1,&c)) { + /* nothing */ +#endif + } else if(name[2]==0) { + c=name[1]; + } else { + return sc->NIL; + } + return mk_character(sc,c); + } else + return (sc->NIL); +} + +/* ========== garbage collector ========== */ + +const int frame_length; +static void dump_stack_deallocate_frame(scheme *sc, pointer frame); + +/*-- + * We use algorithm E (Knuth, The Art of Computer Programming Vol.1, + * sec. 2.3.5), the Schorr-Deutsch-Waite link-inversion algorithm, + * for marking. + */ +static void mark(pointer a) { + pointer t, q, p; + + t = (pointer) 0; + p = a; +E2: if (! is_mark(p)) + setmark(p); + if (is_vector(p) || is_frame(p)) { + int i; + int len = is_vector(p) ? vector_length(p) : frame_length; + for (i = 0; i < len; i++) { + mark(p->_object._vector._elements[i]); + } + } +#if SHOW_ERROR_LINE + else if (is_port(p)) { + port *pt = p->_object._port; + mark(pt->curr_line); + mark(pt->filename); + } +#endif + /* Mark tag if p has one. */ + if (has_tag(p)) + mark(p + 1); + if (is_atom(p)) + goto E6; + /* E4: down car */ + q = car(p); + if (q && !is_mark(q)) { + setatom(p); /* a note that we have moved car */ + car(p) = t; + t = p; + p = q; + goto E2; + } +E5: q = cdr(p); /* down cdr */ + if (q && !is_mark(q)) { + cdr(p) = t; + t = p; + p = q; + goto E2; + } +E6: /* up. Undo the link switching from steps E4 and E5. */ + if (!t) + return; + q = t; + if (is_atom(q)) { + clratom(q); + t = car(q); + car(q) = p; + p = q; + goto E5; + } else { + t = cdr(q); + cdr(q) = p; + p = q; + goto E6; + } +} + +/* garbage collection. parameter a, b is marked. */ +static void gc(scheme *sc, pointer a, pointer b) { + pointer p; + struct cell_segment *s; + int i; + + assert (gc_enabled (sc)); + + if(sc->gc_verbose) { + putstr(sc, "gc..."); + } + + /* mark system globals */ + mark(sc->oblist); + mark(sc->global_env); + + /* mark current registers */ + mark(sc->args); + mark(sc->envir); + mark(sc->code); + history_mark(sc); + dump_stack_mark(sc); + mark(sc->value); + mark(sc->inport); + mark(sc->save_inport); + mark(sc->outport); + mark(sc->loadport); + for (i = 0; i <= sc->file_i; i++) { + mark(sc->load_stack[i].filename); + mark(sc->load_stack[i].curr_line); + } + + /* Mark recent objects the interpreter doesn't know about yet. */ + mark(car(sc->sink)); + /* Mark any older stuff above nested C calls */ + mark(sc->c_nest); + + /* mark variables a, b */ + mark(a); + mark(b); + + /* garbage collect */ + clrmark(sc->NIL); + sc->fcells = 0; + sc->free_cell = sc->NIL; + /* free-list is kept sorted by address so as to maintain consecutive + ranges, if possible, for use with vectors. Here we scan the cells + (which are also kept sorted by address) downwards to build the + free-list in sorted order. + */ + for (s = sc->cell_segments; s; s = s->next) { + p = s->cells + s->cells_len; + while (--p >= s->cells) { + if ((typeflag(p) & 1) == 0) + /* All types have the LSB set. This is not a typeflag. */ + continue; + if (is_mark(p)) { + clrmark(p); + } else { + /* reclaim cell */ + if ((typeflag(p) & T_FINALIZE) == 0 + || finalize_cell(sc, p)) { + /* Reclaim cell. */ + ++sc->fcells; + typeflag(p) = 0; + car(p) = sc->NIL; + cdr(p) = sc->free_cell; + sc->free_cell = p; + } + } + } + } + + if (sc->gc_verbose) { + char msg[80]; + snprintf(msg,80,"done: %ld cells were recovered.\n", sc->fcells); + putstr(sc,msg); + } + + /* if only a few recovered, get more to avoid fruitless gc's */ + if (sc->fcells < CELL_MINRECOVER + && alloc_cellseg(sc, 1) == 0) + sc->no_memory = 1; +} + +/* Finalize A. Returns true if a can be added to the list of free + * cells. */ +static int +finalize_cell(scheme *sc, pointer a) +{ + switch (type(a)) { + case T_STRING: + sc->free(strvalue(a)); + break; + + case T_PORT: + if(a->_object._port->kind&port_file + && a->_object._port->rep.stdio.closeit) { + port_close(sc,a,port_input|port_output); + } else if (a->_object._port->kind & port_srfi6) { + sc->free(a->_object._port->rep.string.start); + } + sc->free(a->_object._port); + break; + + case T_FOREIGN_OBJECT: + a->_object._foreign_object._vtable->finalize(sc, a->_object._foreign_object._data); + break; + + case T_VECTOR: + do { + int i; + for (i = vector_size(vector_length(a)) - 1; i > 0; i--) { + pointer p = a + i; + typeflag(p) = 0; + car(p) = sc->NIL; + cdr(p) = sc->free_cell; + sc->free_cell = p; + sc->fcells += 1; + } + } while (0); + break; + + case T_FRAME: + dump_stack_deallocate_frame(sc, a); + return 0; /* Do not free cell. */ + } + + return 1; /* Free cell. */ +} + +#if SHOW_ERROR_LINE +static void +port_clear_location (scheme *sc, port *p) +{ + p->curr_line = sc->NIL; + p->filename = sc->NIL; +} + +static void +port_increment_current_line (scheme *sc, port *p, long delta) +{ + if (delta == 0) + return; + + p->curr_line = + mk_integer(sc, ivalue_unchecked(p->curr_line) + delta); +} + +static void +port_init_location (scheme *sc, port *p, pointer name) +{ + p->curr_line = mk_integer(sc, 0); + p->filename = name ? name : mk_string(sc, "<unknown>"); +} + +#else + +static void +port_clear_location (scheme *sc, port *p) +{ +} + +static void +port_increment_current_line (scheme *sc, port *p, long delta) +{ +} + +static void +port_init_location (scheme *sc, port *p, pointer name) +{ +} + +#endif + +/* ========== Routines for Reading ========== */ + +static int file_push(scheme *sc, pointer fname) { + FILE *fin = NULL; + + if (sc->file_i == MAXFIL-1) + return 0; + fin = fopen(string_value(fname), "r"); + if(fin!=0) { + sc->file_i++; + sc->load_stack[sc->file_i].kind=port_file|port_input; + sc->load_stack[sc->file_i].rep.stdio.file=fin; + sc->load_stack[sc->file_i].rep.stdio.closeit=1; + sc->nesting_stack[sc->file_i]=0; + sc->loadport->_object._port=sc->load_stack+sc->file_i; + port_init_location(sc, &sc->load_stack[sc->file_i], fname); + } + return fin!=0; +} + +static void file_pop(scheme *sc) { + if(sc->file_i != 0) { + sc->nesting=sc->nesting_stack[sc->file_i]; + port_close(sc,sc->loadport,port_input); + port_clear_location(sc, &sc->load_stack[sc->file_i]); + sc->file_i--; + sc->loadport->_object._port=sc->load_stack+sc->file_i; + } +} + +static int file_interactive(scheme *sc) { + return sc->file_i==0 && sc->load_stack[0].rep.stdio.file==stdin + && sc->inport->_object._port->kind&port_file; +} + +static port *port_rep_from_filename(scheme *sc, const char *fn, int prop) { + FILE *f; + char *rw; + port *pt; + if(prop==(port_input|port_output)) { + rw="a+"; + } else if(prop==port_output) { + rw="w"; + } else { + rw="r"; + } + f=fopen(fn,rw); + if(f==0) { + return 0; + } + pt=port_rep_from_file(sc,f,prop); + pt->rep.stdio.closeit=1; + port_init_location(sc, pt, mk_string(sc, fn)); + return pt; +} + +static pointer port_from_filename(scheme *sc, const char *fn, int prop) { + port *pt; + pt=port_rep_from_filename(sc,fn,prop); + if(pt==0) { + return sc->NIL; + } + return mk_port(sc,pt); +} + +static port *port_rep_from_file(scheme *sc, FILE *f, int prop) +{ + port *pt; + + pt = (port *)sc->malloc(sizeof *pt); + if (pt == NULL) { + return NULL; + } + pt->kind = port_file | prop; + pt->rep.stdio.file = f; + pt->rep.stdio.closeit = 0; + port_init_location(sc, pt, NULL); + return pt; +} + +static pointer port_from_file(scheme *sc, FILE *f, int prop) { + port *pt; + pt=port_rep_from_file(sc,f,prop); + if(pt==0) { + return sc->NIL; + } + return mk_port(sc,pt); +} + +static port *port_rep_from_string(scheme *sc, char *start, char *past_the_end, int prop) { + port *pt; + pt=(port*)sc->malloc(sizeof(port)); + if(pt==0) { + return 0; + } + pt->kind=port_string|prop; + pt->rep.string.start=start; + pt->rep.string.curr=start; + pt->rep.string.past_the_end=past_the_end; + port_init_location(sc, pt, NULL); + return pt; +} + +static pointer port_from_string(scheme *sc, char *start, char *past_the_end, int prop) { + port *pt; + pt=port_rep_from_string(sc,start,past_the_end,prop); + if(pt==0) { + return sc->NIL; + } + return mk_port(sc,pt); +} + +#define BLOCK_SIZE 256 + +static port *port_rep_from_scratch(scheme *sc) { + port *pt; + char *start; + pt=(port*)sc->malloc(sizeof(port)); + if(pt==0) { + return 0; + } + start=sc->malloc(BLOCK_SIZE); + if(start==0) { + return 0; + } + memset(start,' ',BLOCK_SIZE-1); + start[BLOCK_SIZE-1]='\0'; + pt->kind=port_string|port_output|port_srfi6; + pt->rep.string.start=start; + pt->rep.string.curr=start; + pt->rep.string.past_the_end=start+BLOCK_SIZE-1; + port_init_location(sc, pt, NULL); + return pt; +} + +static pointer port_from_scratch(scheme *sc) { + port *pt; + pt=port_rep_from_scratch(sc); + if(pt==0) { + return sc->NIL; + } + return mk_port(sc,pt); +} + +static void port_close(scheme *sc, pointer p, int flag) { + port *pt=p->_object._port; + pt->kind&=~flag; + if((pt->kind & (port_input|port_output))==0) { + /* Cleanup is here so (close-*-port) functions could work too */ + port_clear_location(sc, pt); + if(pt->kind&port_file) { + fclose(pt->rep.stdio.file); + } + pt->kind=port_free; + } +} + +/* get new character from input file */ +static int inchar(scheme *sc) { + int c; + port *pt; + + pt = sc->inport->_object._port; + if(pt->kind & port_saw_EOF) + { return EOF; } + c = basic_inchar(pt); + if(c == EOF && sc->inport == sc->loadport) { + /* Instead, set port_saw_EOF */ + pt->kind |= port_saw_EOF; + + /* file_pop(sc); */ + return EOF; + /* NOTREACHED */ + } + return c; +} + +static int basic_inchar(port *pt) { + if(pt->kind & port_file) { + return fgetc(pt->rep.stdio.file); + } else { + if(*pt->rep.string.curr == 0 || + pt->rep.string.curr == pt->rep.string.past_the_end) { + return EOF; + } else { + return *pt->rep.string.curr++; + } + } +} + +/* back character to input buffer */ +static void backchar(scheme *sc, int c) { + port *pt; + if(c==EOF) return; + pt=sc->inport->_object._port; + if(pt->kind&port_file) { + ungetc(c,pt->rep.stdio.file); + } else { + if(pt->rep.string.curr!=pt->rep.string.start) { + --pt->rep.string.curr; + } + } +} + +static int realloc_port_string(scheme *sc, port *p) +{ + char *start=p->rep.string.start; + size_t old_size = p->rep.string.past_the_end - start; + size_t new_size=p->rep.string.past_the_end-start+1+BLOCK_SIZE; + char *str=sc->malloc(new_size); + if(str) { + memset(str,' ',new_size-1); + str[new_size-1]='\0'; + memcpy(str, start, old_size); + p->rep.string.start=str; + p->rep.string.past_the_end=str+new_size-1; + p->rep.string.curr-=start-str; + sc->free(start); + return 1; + } else { + return 0; + } +} + +INTERFACE void putstr(scheme *sc, const char *s) { + port *pt=sc->outport->_object._port; + if(pt->kind&port_file) { + fputs(s,pt->rep.stdio.file); + } else { + for(;*s;s++) { + if(pt->rep.string.curr!=pt->rep.string.past_the_end) { + *pt->rep.string.curr++=*s; + } else if(pt->kind&port_srfi6&&realloc_port_string(sc,pt)) { + *pt->rep.string.curr++=*s; + } + } + } +} + +static void putchars(scheme *sc, const char *s, int len) { + port *pt=sc->outport->_object._port; + if(pt->kind&port_file) { + fwrite(s,1,len,pt->rep.stdio.file); + } else { + for(;len;len--) { + if(pt->rep.string.curr!=pt->rep.string.past_the_end) { + *pt->rep.string.curr++=*s++; + } else if(pt->kind&port_srfi6&&realloc_port_string(sc,pt)) { + *pt->rep.string.curr++=*s++; + } + } + } +} + +INTERFACE void putcharacter(scheme *sc, int c) { + port *pt=sc->outport->_object._port; + if(pt->kind&port_file) { + fputc(c,pt->rep.stdio.file); + } else { + if(pt->rep.string.curr!=pt->rep.string.past_the_end) { + *pt->rep.string.curr++=c; + } else if(pt->kind&port_srfi6&&realloc_port_string(sc,pt)) { + *pt->rep.string.curr++=c; + } + } +} + +/* read characters up to delimiter, but cater to character constants */ +static char *readstr_upto(scheme *sc, char *delim) { + char *p = sc->strbuff; + + while ((p - sc->strbuff < sc->strbuff_size) && + !is_one_of(delim, (*p++ = inchar(sc)))); + + if(p == sc->strbuff+2 && p[-2] == '\\') { + *p=0; + } else { + backchar(sc,p[-1]); + *--p = '\0'; + } + return sc->strbuff; +} + +/* read string expression "xxx...xxx" */ +static pointer readstrexp(scheme *sc) { + char *p = sc->strbuff; + int c; + int c1=0; + enum { st_ok, st_bsl, st_x1, st_x2, st_oct1, st_oct2 } state=st_ok; + + for (;;) { + c=inchar(sc); + if(c == EOF) { + return sc->F; + } + if(p-sc->strbuff > (sc->strbuff_size)-1) { + ptrdiff_t offset = p - sc->strbuff; + if (expand_strbuff(sc) != 0) { + return sc->F; + } + p = sc->strbuff + offset; + } + switch(state) { + case st_ok: + switch(c) { + case '\\': + state=st_bsl; + break; + case '"': + *p=0; + return mk_counted_string(sc,sc->strbuff,p-sc->strbuff); + default: + *p++=c; + break; + } + break; + case st_bsl: + switch(c) { + case '0': + case '1': + case '2': + case '3': + case '4': + case '5': + case '6': + case '7': + state=st_oct1; + c1=c-'0'; + break; + case 'x': + case 'X': + state=st_x1; + c1=0; + break; + case 'n': + *p++='\n'; + state=st_ok; + break; + case 't': + *p++='\t'; + state=st_ok; + break; + case 'r': + *p++='\r'; + state=st_ok; + break; + case '"': + *p++='"'; + state=st_ok; + break; + default: + *p++=c; + state=st_ok; + break; + } + break; + case st_x1: + case st_x2: + c=toupper(c); + if(c>='0' && c<='F') { + if(c<='9') { + c1=(c1<<4)+c-'0'; + } else { + c1=(c1<<4)+c-'A'+10; + } + if(state==st_x1) { + state=st_x2; + } else { + *p++=c1; + state=st_ok; + } + } else { + return sc->F; + } + break; + case st_oct1: + case st_oct2: + if (c < '0' || c > '7') + { + *p++=c1; + backchar(sc, c); + state=st_ok; + } + else + { + if (state==st_oct2 && c1 >= 32) + return sc->F; + + c1=(c1<<3)+(c-'0'); + + if (state == st_oct1) + state=st_oct2; + else + { + *p++=c1; + state=st_ok; + } + } + break; + + } + } +} + +/* check c is in chars */ +static INLINE int is_one_of(char *s, int c) { + if(c==EOF) return 1; + while (*s) + if (*s++ == c) + return (1); + return (0); +} + +/* skip white characters */ +static INLINE int skipspace(scheme *sc) { + int c = 0, curr_line = 0; + + do { + c=inchar(sc); +#if SHOW_ERROR_LINE + if(c=='\n') + curr_line++; +#endif + } while (isspace(c)); + + /* record it */ + port_increment_current_line(sc, &sc->load_stack[sc->file_i], curr_line); + + if(c!=EOF) { + backchar(sc,c); + return 1; + } + else + { return EOF; } +} + +/* get token */ +static int token(scheme *sc) { + int c; + c = skipspace(sc); + if(c == EOF) { return (TOK_EOF); } + switch (c=inchar(sc)) { + case EOF: + return (TOK_EOF); + case '(': + return (TOK_LPAREN); + case ')': + return (TOK_RPAREN); + case '.': + c=inchar(sc); + if(is_one_of(" \n\t",c)) { + return (TOK_DOT); + } else { + backchar(sc,c); + backchar(sc,'.'); + return TOK_ATOM; + } + case '\'': + return (TOK_QUOTE); + case ';': + while ((c=inchar(sc)) != '\n' && c!=EOF) + ; + + if(c == '\n') + port_increment_current_line(sc, &sc->load_stack[sc->file_i], 1); + + if(c == EOF) + { return (TOK_EOF); } + else + { return (token(sc));} + case '"': + return (TOK_DQUOTE); + case BACKQUOTE: + return (TOK_BQUOTE); + case ',': + if ((c=inchar(sc)) == '@') { + return (TOK_ATMARK); + } else { + backchar(sc,c); + return (TOK_COMMA); + } + case '#': + c=inchar(sc); + if (c == '(') { + return (TOK_VEC); + } else if(c == '!') { + while ((c=inchar(sc)) != '\n' && c!=EOF) + ; + + if(c == '\n') + port_increment_current_line(sc, &sc->load_stack[sc->file_i], 1); + + if(c == EOF) + { return (TOK_EOF); } + else + { return (token(sc));} + } else { + backchar(sc,c); + if(is_one_of(" tfodxb\\",c)) { + return TOK_SHARP_CONST; + } else { + return (TOK_SHARP); + } + } + default: + backchar(sc,c); + return (TOK_ATOM); + } +} + +/* ========== Routines for Printing ========== */ +#define ok_abbrev(x) (is_pair(x) && cdr(x) == sc->NIL) + +static void printslashstring(scheme *sc, char *p, int len) { + int i; + unsigned char *s=(unsigned char*)p; + putcharacter(sc,'"'); + for ( i=0; i<len; i++) { + if(*s==0xff || *s=='"' || *s<' ' || *s=='\\') { + putcharacter(sc,'\\'); + switch(*s) { + case '"': + putcharacter(sc,'"'); + break; + case '\n': + putcharacter(sc,'n'); + break; + case '\t': + putcharacter(sc,'t'); + break; + case '\r': + putcharacter(sc,'r'); + break; + case '\\': + putcharacter(sc,'\\'); + break; + default: { + int d=*s/16; + putcharacter(sc,'x'); + if(d<10) { + putcharacter(sc,d+'0'); + } else { + putcharacter(sc,d-10+'A'); + } + d=*s%16; + if(d<10) { + putcharacter(sc,d+'0'); + } else { + putcharacter(sc,d-10+'A'); + } + } + } + } else { + putcharacter(sc,*s); + } + s++; + } + putcharacter(sc,'"'); +} + + +/* print atoms */ +static void printatom(scheme *sc, pointer l, int f) { + char *p; + int len; + atom2str(sc,l,f,&p,&len); + putchars(sc,p,len); +} + + +/* Uses internal buffer unless string pointer is already available */ +static void atom2str(scheme *sc, pointer l, int f, char **pp, int *plen) { + char *p; + + if (l == sc->NIL) { + p = "()"; + } else if (l == sc->T) { + p = "#t"; + } else if (l == sc->F) { + p = "#f"; + } else if (l == sc->EOF_OBJ) { + p = "#<EOF>"; + } else if (is_port(l)) { + p = "#<PORT>"; + } else if (is_number(l)) { + p = sc->strbuff; + if (f <= 1 || f == 10) /* f is the base for numbers if > 1 */ { + if(num_is_integer(l)) { + snprintf(p, STRBUFFSIZE, "%ld", ivalue_unchecked(l)); + } else { + snprintf(p, STRBUFFSIZE, "%.10g", rvalue_unchecked(l)); + /* r5rs says there must be a '.' (unless 'e'?) */ + f = strcspn(p, ".e"); + if (p[f] == 0) { + p[f] = '.'; /* not found, so add '.0' at the end */ + p[f+1] = '0'; + p[f+2] = 0; + } + } + } else { + long v = ivalue(l); + if (f == 16) { + if (v >= 0) + snprintf(p, STRBUFFSIZE, "%lx", v); + else + snprintf(p, STRBUFFSIZE, "-%lx", -v); + } else if (f == 8) { + if (v >= 0) + snprintf(p, STRBUFFSIZE, "%lo", v); + else + snprintf(p, STRBUFFSIZE, "-%lo", -v); + } else if (f == 2) { + unsigned long b = (v < 0) ? -v : v; + p = &p[STRBUFFSIZE-1]; + *p = 0; + do { *--p = (b&1) ? '1' : '0'; b >>= 1; } while (b != 0); + if (v < 0) *--p = '-'; + } + } + } else if (is_string(l)) { + if (!f) { + *pp = strvalue(l); + *plen = strlength(l); + return; + } else { /* Hack, uses the fact that printing is needed */ + *pp=sc->strbuff; + *plen=0; + printslashstring(sc, strvalue(l), strlength(l)); + return; + } + } else if (is_character(l)) { + int c=charvalue(l); + p = sc->strbuff; + if (!f) { + p[0]=c; + p[1]=0; + } else { + switch(c) { + case ' ': + p = "#\\space"; + break; + case '\n': + p = "#\\newline"; + break; + case '\r': + p = "#\\return"; + break; + case '\t': + p = "#\\tab"; + break; + default: +#if USE_ASCII_NAMES + if(c==127) { + p = "#\\del"; + break; + } else if(c<32) { + snprintf(p,STRBUFFSIZE, "#\\%s",charnames[c]); + break; + } +#else + if(c<32) { + snprintf(p,STRBUFFSIZE,"#\\x%x",c); + break; + } +#endif + snprintf(p,STRBUFFSIZE,"#\\%c",c); + break; + } + } + } else if (is_symbol(l)) { + p = symname(l); + } else if (is_proc(l)) { + p = sc->strbuff; + snprintf(p,STRBUFFSIZE,"#<%s PROCEDURE %ld>", procname(l),procnum(l)); + } else if (is_macro(l)) { + p = "#<MACRO>"; + } else if (is_closure(l)) { + p = "#<CLOSURE>"; + } else if (is_promise(l)) { + p = "#<PROMISE>"; + } else if (is_foreign(l)) { + p = sc->strbuff; + snprintf(p,STRBUFFSIZE,"#<FOREIGN PROCEDURE %ld>", procnum(l)); + } else if (is_continuation(l)) { + p = "#<CONTINUATION>"; + } else if (is_foreign_object(l)) { + p = sc->strbuff; + l->_object._foreign_object._vtable->to_string(sc, p, STRBUFFSIZE, l->_object._foreign_object._data); + } else { + p = "#<ERROR>"; + } + *pp=p; + *plen=strlen(p); +} +/* ========== Routines for Evaluation Cycle ========== */ + +/* make closure. c is code. e is environment */ +static pointer mk_closure(scheme *sc, pointer c, pointer e) { + pointer x = get_cell(sc, c, e); + + typeflag(x) = T_CLOSURE; + car(x) = c; + cdr(x) = e; + return (x); +} + +/* make continuation. */ +static pointer mk_continuation(scheme *sc, pointer d) { + pointer x = get_cell(sc, sc->NIL, d); + + typeflag(x) = T_CONTINUATION; + cont_dump(x) = d; + return (x); +} + +static pointer list_star(scheme *sc, pointer d) { + pointer p, q; + if(cdr(d)==sc->NIL) { + return car(d); + } + p=cons(sc,car(d),cdr(d)); + q=p; + while(cdr(cdr(p))!=sc->NIL) { + d=cons(sc,car(p),cdr(p)); + if(cdr(cdr(p))!=sc->NIL) { + p=cdr(d); + } + } + cdr(p)=car(cdr(p)); + return q; +} + +/* reverse list -- produce new list */ +static pointer reverse(scheme *sc, pointer term, pointer list) { +/* a must be checked by gc */ + pointer a = list, p = term; + + for ( ; is_pair(a); a = cdr(a)) { + p = cons(sc, car(a), p); + } + return (p); +} + +/* reverse list --- in-place */ +static pointer reverse_in_place(scheme *sc, pointer term, pointer list) { + pointer p = list, result = term, q; + + while (p != sc->NIL) { + q = cdr(p); + cdr(p) = result; + result = p; + p = q; + } + return (result); +} + +/* append list -- produce new list (in reverse order) */ +static pointer revappend(scheme *sc, pointer a, pointer b) { + pointer result = a; + pointer p = b; + + while (is_pair(p)) { + result = cons(sc, car(p), result); + p = cdr(p); + } + + if (p == sc->NIL) { + return result; + } + + return sc->F; /* signal an error */ +} + +/* equivalence of atoms */ +int eqv(pointer a, pointer b) { + if (is_string(a)) { + if (is_string(b)) + return (strvalue(a) == strvalue(b)); + else + return (0); + } else if (is_number(a)) { + if (is_number(b)) { + if (num_is_integer(a) == num_is_integer(b)) + return num_eq(nvalue(a),nvalue(b)); + } + return (0); + } else if (is_character(a)) { + if (is_character(b)) + return charvalue(a)==charvalue(b); + else + return (0); + } else if (is_port(a)) { + if (is_port(b)) + return a==b; + else + return (0); + } else if (is_proc(a)) { + if (is_proc(b)) + return procnum(a)==procnum(b); + else + return (0); + } else { + return (a == b); + } +} + +/* true or false value macro */ +/* () is #t in R5RS */ +#define is_true(p) ((p) != sc->F) +#define is_false(p) ((p) == sc->F) + + +/* ========== Environment implementation ========== */ + +#if !defined(USE_ALIST_ENV) || !defined(USE_OBJECT_LIST) + +static int hash_fn(const char *key, int table_size) +{ + unsigned int hashed = 0; + const char *c; + int bits_per_int = sizeof(unsigned int)*8; + + for (c = key; *c; c++) { + /* letters have about 5 bits in them */ + hashed = (hashed<<5) | (hashed>>(bits_per_int-5)); + hashed ^= *c; + } + return hashed % table_size; +} +#endif + +/* Compares A and B. Returns an integer less than, equal to, or + * greater than zero if A is stored at a memory location that is + * numerical less than, equal to, or greater than that of B. */ +static int +pointercmp(pointer a, pointer b) +{ + uintptr_t a_n = (uintptr_t) a; + uintptr_t b_n = (uintptr_t) b; + + if (a_n < b_n) + return -1; + if (a_n > b_n) + return 1; + return 0; +} + +#ifndef USE_ALIST_ENV + +/* + * In this implementation, each frame of the environment may be + * a hash table: a vector of alists hashed by variable name. + * In practice, we use a vector only for the initial frame; + * subsequent frames are too small and transient for the lookup + * speed to out-weigh the cost of making a new vector. + */ + +static void new_frame_in_env(scheme *sc, pointer old_env) +{ + pointer new_frame; + + /* The interaction-environment has about 480 variables in it. */ + if (old_env == sc->NIL) { + new_frame = mk_vector(sc, 751); + } else { + new_frame = sc->NIL; + } + + gc_disable(sc, 1); + sc->envir = immutable_cons(sc, new_frame, old_env); + gc_enable(sc); + setenvironment(sc->envir); +} + +/* Find the slot in ENV under the key HDL. If ALL is given, look in + * all environments enclosing ENV. If the lookup fails, and SSLOT is + * given, the position where the new slot has to be inserted is stored + * at SSLOT. */ +static pointer +find_slot_spec_in_env(scheme *sc, pointer env, pointer hdl, int all, pointer **sslot) +{ + pointer x,y; + int location; + pointer *sl; + int d; + assert(is_symbol(hdl)); + + for (x = env; x != sc->NIL; x = cdr(x)) { + if (is_vector(car(x))) { + location = hash_fn(symname(hdl), vector_length(car(x))); + sl = vector_elem_slot(car(x), location); + } else { + sl = &car(x); + } + for (y = *sl ; y != sc->NIL; sl = &cdr(y), y = *sl) { + d = pointercmp(caar(y), hdl); + if (d == 0) + return car(y); /* Hit. */ + else if (d > 0) + break; /* Miss. */ + } + + if (x == env && sslot) + *sslot = sl; /* Insert here. */ + + if (!all) + return sc->NIL; /* Miss, and stop looking. */ + } + + return sc->NIL; /* Not found in any environment. */ +} + +#else /* USE_ALIST_ENV */ + +static INLINE void new_frame_in_env(scheme *sc, pointer old_env) +{ + sc->envir = immutable_cons(sc, sc->NIL, old_env); + setenvironment(sc->envir); +} + +/* Find the slot in ENV under the key HDL. If ALL is given, look in + * all environments enclosing ENV. If the lookup fails, and SSLOT is + * given, the position where the new slot has to be inserted is stored + * at SSLOT. */ +static pointer +find_slot_spec_in_env(scheme *sc, pointer env, pointer hdl, int all, pointer **sslot) +{ + pointer x,y; + pointer *sl; + int d; + assert(is_symbol(hdl)); + + for (x = env; x != sc->NIL; x = cdr(x)) { + for (sl = &car(x), y = *sl; y != sc->NIL; sl = &cdr(y), y = *sl) { + d = pointercmp(caar(y), hdl); + if (d == 0) + return car(y); /* Hit. */ + else if (d > 0) + break; /* Miss. */ + } + + if (x == env && sslot) + *sslot = sl; /* Insert here. */ + + if (!all) + return sc->NIL; /* Miss, and stop looking. */ + } + + return sc->NIL; /* Not found in any environment. */ +} + +#endif /* USE_ALIST_ENV else */ + +static pointer find_slot_in_env(scheme *sc, pointer env, pointer hdl, int all) +{ + return find_slot_spec_in_env(sc, env, hdl, all, NULL); +} + +/* Insert (VARIABLE, VALUE) at SSLOT. SSLOT must be obtained using + * find_slot_spec_in_env, and no insertion must be done between + * obtaining SSLOT and the call to this function. */ +static INLINE void new_slot_spec_in_env(scheme *sc, + pointer variable, pointer value, + pointer *sslot) +{ +#define new_slot_spec_in_env_allocates 2 + pointer slot; + gc_disable(sc, gc_reservations (new_slot_spec_in_env)); + slot = immutable_cons(sc, variable, value); + *sslot = immutable_cons(sc, slot, *sslot); + gc_enable(sc); +} + +static INLINE void new_slot_in_env(scheme *sc, pointer variable, pointer value) +{ +#define new_slot_in_env_allocates new_slot_spec_in_env_allocates + pointer slot; + pointer *sslot; + assert(is_symbol(variable)); + slot = find_slot_spec_in_env(sc, sc->envir, variable, 0, &sslot); + assert(slot == sc->NIL); + new_slot_spec_in_env(sc, variable, value, sslot); +} + +static INLINE void set_slot_in_env(scheme *sc, pointer slot, pointer value) +{ + (void)sc; + cdr(slot) = value; +} + +static INLINE pointer slot_value_in_env(pointer slot) +{ + return cdr(slot); +} + + +/* ========== Evaluation Cycle ========== */ + + +static enum scheme_opcodes +_Error_1(scheme *sc, const char *s, pointer a) { + const char *str = s; + pointer history; +#if USE_ERROR_HOOK + pointer x; + pointer hdl=sc->ERROR_HOOK; +#endif + +#if SHOW_ERROR_LINE + char sbuf[STRBUFFSIZE]; +#endif + + history = history_flatten(sc); + +#if SHOW_ERROR_LINE + /* make sure error is not in REPL */ + if (((sc->load_stack[sc->file_i].kind & port_file) == 0 + || sc->load_stack[sc->file_i].rep.stdio.file != stdin)) { + pointer tag; + const char *fname; + int ln; + + if (history != sc->NIL && has_tag(car(history)) + && (tag = get_tag(sc, car(history))) + && is_string(car(tag)) && is_integer(cdr(tag))) { + fname = string_value(car(tag)); + ln = ivalue_unchecked(cdr(tag)); + } else { + fname = string_value(sc->load_stack[sc->file_i].filename); + ln = ivalue_unchecked(sc->load_stack[sc->file_i].curr_line); + } + + /* should never happen */ + if(!fname) fname = "<unknown>"; + + /* we started from 0 */ + ln++; + snprintf(sbuf, STRBUFFSIZE, "%s:%i: %s", fname, ln, s); + + str = (const char*)sbuf; + } +#endif + +#if USE_ERROR_HOOK + x=find_slot_in_env(sc,sc->envir,hdl,1); + if (x != sc->NIL) { + sc->code = cons(sc, cons(sc, sc->QUOTE, + cons(sc, history, sc->NIL)), + sc->NIL); + if(a!=0) { + sc->code = cons(sc, cons(sc, sc->QUOTE, cons(sc, a, sc->NIL)), + sc->code); + } else { + sc->code = cons(sc, sc->F, sc->code); + } + sc->code = cons(sc, mk_string(sc, str), sc->code); + setimmutable(car(sc->code)); + sc->code = cons(sc, slot_value_in_env(x), sc->code); + return OP_EVAL; + } +#endif + + if(a!=0) { + sc->args = cons(sc, (a), sc->NIL); + } else { + sc->args = sc->NIL; + } + sc->args = cons(sc, mk_string(sc, str), sc->args); + setimmutable(car(sc->args)); + return OP_ERR0; +} +#define Error_1(sc,s, a) { op = _Error_1(sc,s,a); goto dispatch; } +#define Error_0(sc,s) { op = _Error_1(sc,s,0); goto dispatch; } + +/* Too small to turn into function */ +# define BEGIN do { +# define END } while (0) + + + +/* Flags. The interpreter has a flags field. When the interpreter + * pushes a frame to the dump stack, it is encoded with the opcode. + * Therefore, we do not use the least significant byte. */ + +/* Masks used to encode and decode opcode and flags. */ +#define S_OP_MASK 0x000000ff +#define S_FLAG_MASK 0xffffff00 + +/* Set if the interpreter evaluates an expression in a tail context + * (see R5RS, section 3.5). If a function, procedure, or continuation + * is invoked while this flag is set, the call is recorded as tail + * call in the history buffer. */ +#define S_FLAG_TAIL_CONTEXT 0x00000100 + +/* Set flag F. */ +#define s_set_flag(sc, f) \ + BEGIN \ + (sc)->flags |= S_FLAG_ ## f; \ + END + +/* Clear flag F. */ +#define s_clear_flag(sc, f) \ + BEGIN \ + (sc)->flags &= ~ S_FLAG_ ## f; \ + END + +/* Check if flag F is set. */ +#define s_get_flag(sc, f) \ + !!((sc)->flags & S_FLAG_ ## f) + + + +/* Bounce back to Eval_Cycle and execute A. */ +#define s_goto(sc, a) { op = (a); goto dispatch; } + +#if USE_THREADED_CODE + +/* Do not bounce back to Eval_Cycle but execute A by jumping directly + * to it. */ +#define s_thread_to(sc, a) \ + BEGIN \ + op = (a); \ + goto a; \ + END + +/* Define a label OP and emit a case statement for OP. For use in the + * dispatch function. The slightly peculiar goto that is never + * executed avoids warnings about unused labels. */ +#define CASE(OP) case OP: if (0) goto OP; OP + +#else /* USE_THREADED_CODE */ +#define s_thread_to(sc, a) s_goto(sc, a) +#define CASE(OP) case OP +#endif /* USE_THREADED_CODE */ + +/* Return to the previous frame on the dump stack, setting the current + * value to A. */ +#define s_return(sc, a) s_goto(sc, _s_return(sc, a, 0)) + +/* Return to the previous frame on the dump stack, setting the current + * value to A, and re-enable the garbage collector. */ +#define s_return_enable_gc(sc, a) s_goto(sc, _s_return(sc, a, 1)) + +static INLINE void dump_stack_reset(scheme *sc) +{ + sc->dump = sc->NIL; +} + +static INLINE void dump_stack_initialize(scheme *sc) +{ + dump_stack_reset(sc); + sc->frame_freelist = sc->NIL; +} + +static void dump_stack_free(scheme *sc) +{ + dump_stack_initialize(sc); +} + +const int frame_length = 4; + +static pointer +dump_stack_make_frame(scheme *sc) +{ + pointer frame; + + frame = mk_vector(sc, frame_length); + if (! sc->no_memory) + setframe(frame); + + return frame; +} + +static INLINE pointer * +frame_slots(pointer frame) +{ + return &frame->_object._vector._elements[0]; +} + +#define frame_payload vector_length + +static pointer +dump_stack_allocate_frame(scheme *sc) +{ + pointer frame = sc->frame_freelist; + if (frame == sc->NIL) { + if (gc_enabled(sc)) + frame = dump_stack_make_frame(sc); + else + gc_reservation_failure(sc); + } else + sc->frame_freelist = *frame_slots(frame); + return frame; +} + +static void +dump_stack_deallocate_frame(scheme *sc, pointer frame) +{ + pointer *p = frame_slots(frame); + *p++ = sc->frame_freelist; + *p++ = sc->NIL; + *p++ = sc->NIL; + *p++ = sc->NIL; + sc->frame_freelist = frame; +} + +static void +dump_stack_preallocate_frame(scheme *sc) +{ + pointer frame = dump_stack_make_frame(sc); + if (! sc->no_memory) + dump_stack_deallocate_frame(sc, frame); +} + +static enum scheme_opcodes +_s_return(scheme *sc, pointer a, int enable_gc) { + pointer dump = sc->dump; + pointer *p; + unsigned long v; + enum scheme_opcodes next_op; + sc->value = (a); + if (enable_gc) + gc_enable(sc); + if (dump == sc->NIL) + return OP_QUIT; + v = frame_payload(dump); + next_op = (int) (v & S_OP_MASK); + sc->flags = v & S_FLAG_MASK; + p = frame_slots(dump); + sc->args = *p++; + sc->envir = *p++; + sc->code = *p++; + sc->dump = *p++; + dump_stack_deallocate_frame(sc, dump); + return next_op; +} + +static void s_save(scheme *sc, enum scheme_opcodes op, pointer args, pointer code) { +#define s_save_allocates 0 + pointer dump; + pointer *p; + gc_disable(sc, gc_reservations (s_save)); + dump = dump_stack_allocate_frame(sc); + frame_payload(dump) = (size_t) (sc->flags | (unsigned long) op); + p = frame_slots(dump); + *p++ = args; + *p++ = sc->envir; + *p++ = code; + *p++ = sc->dump; + sc->dump = dump; + gc_enable(sc); +} + +static INLINE void dump_stack_mark(scheme *sc) +{ + mark(sc->dump); + mark(sc->frame_freelist); +} + + + +#if USE_HISTORY + +static void +history_free(scheme *sc) +{ + sc->free(sc->history.m); + sc->history.tailstacks = sc->NIL; + sc->history.callstack = sc->NIL; +} + +static pointer +history_init(scheme *sc, size_t N, size_t M) +{ + size_t i; + struct history *h = &sc->history; + + h->N = N; + h->mask_N = N - 1; + h->n = N - 1; + assert ((N & h->mask_N) == 0); + + h->M = M; + h->mask_M = M - 1; + assert ((M & h->mask_M) == 0); + + h->callstack = mk_vector(sc, N); + if (h->callstack == sc->sink) + goto fail; + + h->tailstacks = mk_vector(sc, N); + for (i = 0; i < N; i++) { + pointer tailstack = mk_vector(sc, M); + if (tailstack == sc->sink) + goto fail; + set_vector_elem(h->tailstacks, i, tailstack); + } + + h->m = sc->malloc(N * sizeof *h->m); + if (h->m == NULL) + goto fail; + + for (i = 0; i < N; i++) + h->m[i] = 0; + + return sc->T; + +fail: + history_free(sc); + return sc->F; +} + +static void +history_mark(scheme *sc) +{ + struct history *h = &sc->history; + mark(h->callstack); + mark(h->tailstacks); +} + +#define add_mod(a, b, mask) (((a) + (b)) & (mask)) +#define sub_mod(a, b, mask) add_mod(a, (mask) + 1 - (b), mask) + +static INLINE void +tailstack_clear(scheme *sc, pointer v) +{ + assert(is_vector(v)); + /* XXX optimize */ + fill_vector(v, sc->NIL); +} + +static pointer +callstack_pop(scheme *sc) +{ + struct history *h = &sc->history; + size_t n = h->n; + pointer item; + + if (h->callstack == sc->NIL) + return sc->NIL; + + item = vector_elem(h->callstack, n); + /* Clear our frame so that it can be gc'ed and we don't run into it + * when walking the history. */ + set_vector_elem(h->callstack, n, sc->NIL); + tailstack_clear(sc, vector_elem(h->tailstacks, n)); + + /* Exit from the frame. */ + h->n = sub_mod(h->n, 1, h->mask_N); + + return item; +} + +static void +callstack_push(scheme *sc, pointer item) +{ + struct history *h = &sc->history; + size_t n = h->n; + + if (h->callstack == sc->NIL) + return; + + /* Enter a new frame. */ + n = h->n = add_mod(n, 1, h->mask_N); + + /* Initialize tail stack. */ + tailstack_clear(sc, vector_elem(h->tailstacks, n)); + h->m[n] = h->mask_M; + + set_vector_elem(h->callstack, n, item); +} + +static void +tailstack_push(scheme *sc, pointer item) +{ + struct history *h = &sc->history; + size_t n = h->n; + size_t m = h->m[n]; + + if (h->callstack == sc->NIL) + return; + + /* Enter a new tail frame. */ + m = h->m[n] = add_mod(m, 1, h->mask_M); + set_vector_elem(vector_elem(h->tailstacks, n), m, item); +} + +static pointer +tailstack_flatten(scheme *sc, pointer tailstack, size_t i, size_t n, + pointer acc) +{ + struct history *h = &sc->history; + pointer frame; + + assert(i <= h->M); + assert(n < h->M); + + if (acc == sc->sink) + return sc->sink; + + if (i == 0) { + /* We reached the end, but we did not see a unused frame. Signal + this using '... . */ + return cons(sc, mk_symbol(sc, "..."), acc); + } + + frame = vector_elem(tailstack, n); + if (frame == sc->NIL) { + /* A unused frame. We reached the end of the history. */ + return acc; + } + + /* Add us. */ + acc = cons(sc, frame, acc); + + return tailstack_flatten(sc, tailstack, i - 1, sub_mod(n, 1, h->mask_M), + acc); +} + +static pointer +callstack_flatten(scheme *sc, size_t i, size_t n, pointer acc) +{ + struct history *h = &sc->history; + pointer frame; + + assert(i <= h->N); + assert(n < h->N); + + if (acc == sc->sink) + return sc->sink; + + if (i == 0) { + /* We reached the end, but we did not see a unused frame. Signal + this using '... . */ + return cons(sc, mk_symbol(sc, "..."), acc); + } + + frame = vector_elem(h->callstack, n); + if (frame == sc->NIL) { + /* A unused frame. We reached the end of the history. */ + return acc; + } + + /* First, emit the tail calls. */ + acc = tailstack_flatten(sc, vector_elem(h->tailstacks, n), h->M, h->m[n], + acc); + + /* Then us. */ + acc = cons(sc, frame, acc); + + return callstack_flatten(sc, i - 1, sub_mod(n, 1, h->mask_N), acc); +} + +static pointer +history_flatten(scheme *sc) +{ + struct history *h = &sc->history; + pointer history; + + if (h->callstack == sc->NIL) + return sc->NIL; + + history = callstack_flatten(sc, h->N, h->n, sc->NIL); + if (history == sc->sink) + return sc->sink; + + return reverse_in_place(sc, sc->NIL, history); +} + +#undef add_mod +#undef sub_mod + +#else /* USE_HISTORY */ + +#define history_init(SC, A, B) (void) 0 +#define history_free(SC) (void) 0 +#define callstack_pop(SC) (void) 0 +#define callstack_push(SC, X) (void) 0 +#define tailstack_push(SC, X) (void) 0 + +#endif /* USE_HISTORY */ + + + +#if USE_PLIST +static pointer +get_property(scheme *sc, pointer obj, pointer key) +{ + pointer x; + + assert (is_symbol(obj)); + assert (is_symbol(key)); + + for (x = symprop(obj); x != sc->NIL; x = cdr(x)) { + if (caar(x) == key) + break; + } + + if (x != sc->NIL) + return cdar(x); + + return sc->NIL; +} + +static pointer +set_property(scheme *sc, pointer obj, pointer key, pointer value) +{ +#define set_property_allocates 2 + pointer x; + + assert (is_symbol(obj)); + assert (is_symbol(key)); + + for (x = symprop(obj); x != sc->NIL; x = cdr(x)) { + if (caar(x) == key) + break; + } + + if (x != sc->NIL) + cdar(x) = value; + else { + gc_disable(sc, gc_reservations(set_property)); + symprop(obj) = cons(sc, cons(sc, key, value), symprop(obj)); + gc_enable(sc); + } + + return sc->T; +} +#endif + + + +static int is_list(scheme *sc, pointer a) +{ return list_length(sc,a) >= 0; } + +/* Result is: + proper list: length + circular list: -1 + not even a pair: -2 + dotted list: -2 minus length before dot +*/ +int list_length(scheme *sc, pointer a) { + int i=0; + pointer slow, fast; + + slow = fast = a; + while (1) + { + if (fast == sc->NIL) + return i; + if (!is_pair(fast)) + return -2 - i; + fast = cdr(fast); + ++i; + if (fast == sc->NIL) + return i; + if (!is_pair(fast)) + return -2 - i; + ++i; + fast = cdr(fast); + + /* Safe because we would have already returned if `fast' + encountered a non-pair. */ + slow = cdr(slow); + if (fast == slow) + { + /* the fast pointer has looped back around and caught up + with the slow pointer, hence the structure is circular, + not of finite length, and therefore not a list */ + return -1; + } + } +} + + + +#if GPGRT_GCC_VERSION >= 80000 +# pragma GCC diagnostic push +# pragma GCC diagnostic ignored "-Wimplicit-fallthrough" +#endif + +#define s_retbool(tf) s_return(sc,(tf) ? sc->T : sc->F) + +/* kernel of this interpreter */ +static void +Eval_Cycle(scheme *sc, enum scheme_opcodes op) { + for (;;) { + pointer x, y; + pointer callsite; + num v; +#if USE_MATH + double dd; +#endif + int (*comp_func)(num, num) = NULL; + const struct op_code_info *pcd; + + dispatch: + pcd = &dispatch_table[op]; + if (pcd->name[0] != 0) { /* if built-in function, check arguments */ + char msg[STRBUFFSIZE]; + if (! check_arguments (sc, pcd, msg, sizeof msg)) { + s_goto(sc, _Error_1(sc, msg, 0)); + } + } + + if(sc->no_memory) { + fprintf(stderr,"No memory!\n"); + exit(1); + } + ok_to_freely_gc(sc); + + switch (op) { + CASE(OP_LOAD): /* load */ + if(file_interactive(sc)) { + fprintf(sc->outport->_object._port->rep.stdio.file, + "Loading %s\n", strvalue(car(sc->args))); + } + if (!file_push(sc, car(sc->args))) { + Error_1(sc,"unable to open", car(sc->args)); + } + else + { + sc->args = mk_integer(sc,sc->file_i); + s_thread_to(sc,OP_T0LVL); + } + + CASE(OP_T0LVL): /* top level */ + /* If we reached the end of file, this loop is done. */ + if(sc->loadport->_object._port->kind & port_saw_EOF) + { + if(sc->file_i == 0) + { + sc->args=sc->NIL; + sc->nesting = sc->nesting_stack[0]; + s_thread_to(sc,OP_QUIT); + } + else + { + file_pop(sc); + s_return(sc,sc->value); + } + /* NOTREACHED */ + } + + /* If interactive, be nice to user. */ + if(file_interactive(sc)) + { + sc->envir = sc->global_env; + dump_stack_reset(sc); + putstr(sc,"\n"); + putstr(sc,prompt); + } + + /* Set up another iteration of REPL */ + sc->nesting=0; + sc->save_inport=sc->inport; + sc->inport = sc->loadport; + s_save(sc,OP_T0LVL, sc->NIL, sc->NIL); + s_save(sc,OP_VALUEPRINT, sc->NIL, sc->NIL); + s_save(sc,OP_T1LVL, sc->NIL, sc->NIL); + s_thread_to(sc,OP_READ_INTERNAL); + + CASE(OP_T1LVL): /* top level */ + sc->code = sc->value; + sc->inport=sc->save_inport; + s_thread_to(sc,OP_EVAL); + + CASE(OP_READ_INTERNAL): /* internal read */ + sc->tok = token(sc); + if(sc->tok==TOK_EOF) + { s_return(sc,sc->EOF_OBJ); } + s_thread_to(sc,OP_RDSEXPR); + + CASE(OP_GENSYM): + s_return(sc, gensym(sc)); + + CASE(OP_VALUEPRINT): /* print evaluation result */ + /* OP_VALUEPRINT is always pushed, because when changing from + non-interactive to interactive mode, it needs to be + already on the stack */ + if(sc->tracing) { + putstr(sc,"\nGives: "); + } + if(file_interactive(sc)) { + sc->print_flag = 1; + sc->args = sc->value; + s_thread_to(sc,OP_P0LIST); + } else { + s_return(sc,sc->value); + } + + CASE(OP_EVAL): /* main part of evaluation */ +#if USE_TRACING + if(sc->tracing) { + /*s_save(sc,OP_VALUEPRINT,sc->NIL,sc->NIL);*/ + s_save(sc,OP_REAL_EVAL,sc->args,sc->code); + sc->args=sc->code; + putstr(sc,"\nEval: "); + s_thread_to(sc,OP_P0LIST); + } + /* fall through */ + CASE(OP_REAL_EVAL): +#endif + if (is_symbol(sc->code)) { /* symbol */ + x=find_slot_in_env(sc,sc->envir,sc->code,1); + if (x != sc->NIL) { + s_return(sc,slot_value_in_env(x)); + } else { + Error_1(sc, "eval: unbound variable", sc->code); + } + } else if (is_pair(sc->code)) { + if (is_syntax(x = car(sc->code))) { /* SYNTAX */ + sc->code = cdr(sc->code); + s_goto(sc, syntaxnum(sc, x)); + } else {/* first, eval top element and eval arguments */ + s_save(sc,OP_E0ARGS, sc->NIL, sc->code); + /* If no macros => s_save(sc,OP_E1ARGS, sc->NIL, cdr(sc->code));*/ + sc->code = car(sc->code); + s_clear_flag(sc, TAIL_CONTEXT); + s_thread_to(sc,OP_EVAL); + } + } else { + s_return(sc,sc->code); + } + + CASE(OP_E0ARGS): /* eval arguments */ + if (is_macro(sc->value)) { /* macro expansion */ + gc_disable(sc, 1 + gc_reservations (s_save)); + s_save(sc,OP_DOMACRO, sc->NIL, sc->NIL); + sc->args = cons(sc,sc->code, sc->NIL); + gc_enable(sc); + sc->code = sc->value; + s_clear_flag(sc, TAIL_CONTEXT); + s_thread_to(sc,OP_APPLY); + } else { + gc_disable(sc, 1); + sc->args = cons(sc, sc->code, sc->NIL); + gc_enable(sc); + sc->code = cdr(sc->code); + s_thread_to(sc,OP_E1ARGS); + } + + CASE(OP_E1ARGS): /* eval arguments */ + gc_disable(sc, 1); + sc->args = cons(sc, sc->value, sc->args); + gc_enable(sc); + if (is_pair(sc->code)) { /* continue */ + s_save(sc,OP_E1ARGS, sc->args, cdr(sc->code)); + sc->code = car(sc->code); + sc->args = sc->NIL; + s_clear_flag(sc, TAIL_CONTEXT); + s_thread_to(sc,OP_EVAL); + } else { /* end */ + sc->args = reverse_in_place(sc, sc->NIL, sc->args); + s_thread_to(sc,OP_APPLY_CODE); + } + +#if USE_TRACING + CASE(OP_TRACING): { + int tr=sc->tracing; + sc->tracing=ivalue(car(sc->args)); + gc_disable(sc, 1); + s_return_enable_gc(sc, mk_integer(sc, tr)); + } +#endif + +#if USE_HISTORY + CASE(OP_CALLSTACK_POP): /* pop the call stack */ + callstack_pop(sc); + s_return(sc, sc->value); +#endif + + CASE(OP_APPLY_CODE): /* apply 'cadr(args)' to 'cddr(args)', + * record in the history as invoked from + * 'car(args)' */ + free_cons(sc, sc->args, &callsite, &sc->args); + sc->code = car(sc->args); + sc->args = cdr(sc->args); + /* Fallthrough. */ + + CASE(OP_APPLY): /* apply 'code' to 'args' */ +#if USE_TRACING + if(sc->tracing) { + s_save(sc,OP_REAL_APPLY,sc->args,sc->code); + sc->print_flag = 1; + /* sc->args=cons(sc,sc->code,sc->args);*/ + putstr(sc,"\nApply to: "); + s_thread_to(sc,OP_P0LIST); + } + /* fall through */ + CASE(OP_REAL_APPLY): +#endif +#if USE_HISTORY + if (op != OP_APPLY_CODE) + callsite = sc->code; + if (s_get_flag(sc, TAIL_CONTEXT)) { + /* We are evaluating a tail call. */ + tailstack_push(sc, callsite); + } else { + callstack_push(sc, callsite); + s_save(sc, OP_CALLSTACK_POP, sc->NIL, sc->NIL); + } +#endif + + if (is_proc(sc->code)) { + s_goto(sc,procnum(sc->code)); /* PROCEDURE */ + } else if (is_foreign(sc->code)) + { + /* Keep nested calls from GC'ing the arglist */ + push_recent_alloc(sc,sc->args,sc->NIL); + x=sc->code->_object._ff(sc,sc->args); + s_return(sc,x); + } else if (is_closure(sc->code) || is_macro(sc->code) + || is_promise(sc->code)) { /* CLOSURE */ + /* Should not accept promise */ + /* make environment */ + new_frame_in_env(sc, closure_env(sc->code)); + for (x = car(closure_code(sc->code)), y = sc->args; + is_pair(x); x = cdr(x), y = cdr(y)) { + if (y == sc->NIL) { + Error_1(sc, "not enough arguments, missing", x); + } else if (is_symbol(car(x))) { + new_slot_in_env(sc, car(x), car(y)); + } else { + Error_1(sc, "syntax error in closure: not a symbol", car(x)); + } + } + + if (x == sc->NIL) { + if (y != sc->NIL) { + Error_0(sc, "too many arguments"); + } + } else if (is_symbol(x)) + new_slot_in_env(sc, x, y); + else { + Error_1(sc, "syntax error in closure: not a symbol", x); + } + sc->code = cdr(closure_code(sc->code)); + sc->args = sc->NIL; + s_set_flag(sc, TAIL_CONTEXT); + s_thread_to(sc,OP_BEGIN); + } else if (is_continuation(sc->code)) { /* CONTINUATION */ + sc->dump = cont_dump(sc->code); + s_return(sc,sc->args != sc->NIL ? car(sc->args) : sc->NIL); + } else { + Error_1(sc,"illegal function",sc->code); + } + + CASE(OP_DOMACRO): /* do macro */ + sc->code = sc->value; + s_thread_to(sc,OP_EVAL); + +#if USE_COMPILE_HOOK + CASE(OP_LAMBDA): /* lambda */ + /* If the hook is defined, apply it to sc->code, otherwise + set sc->value fall through */ + { + pointer f=find_slot_in_env(sc,sc->envir,sc->COMPILE_HOOK,1); + if(f==sc->NIL) { + sc->value = sc->code; + /* Fallthru */ + } else { + gc_disable(sc, 1 + gc_reservations (s_save)); + s_save(sc,OP_LAMBDA1,sc->args,sc->code); + sc->args=cons(sc,sc->code,sc->NIL); + gc_enable(sc); + sc->code=slot_value_in_env(f); + s_thread_to(sc,OP_APPLY); + } + } + /* Fallthrough. */ +#else + CASE(OP_LAMBDA): /* lambda */ + sc->value = sc->code; + /* Fallthrough. */ +#endif + + CASE(OP_LAMBDA1): + gc_disable(sc, 1); + s_return_enable_gc(sc, mk_closure(sc, sc->value, sc->envir)); + + + CASE(OP_MKCLOSURE): /* make-closure */ + x=car(sc->args); + if(car(x)==sc->LAMBDA) { + x=cdr(x); + } + if(cdr(sc->args)==sc->NIL) { + y=sc->envir; + } else { + y=cadr(sc->args); + } + gc_disable(sc, 1); + s_return_enable_gc(sc, mk_closure(sc, x, y)); + + CASE(OP_QUOTE): /* quote */ + s_return(sc,car(sc->code)); + + CASE(OP_DEF0): /* define */ + if(is_immutable(car(sc->code))) + Error_1(sc,"define: unable to alter immutable", car(sc->code)); + + if (is_pair(car(sc->code))) { + x = caar(sc->code); + gc_disable(sc, 2); + sc->code = cons(sc, sc->LAMBDA, cons(sc, cdar(sc->code), cdr(sc->code))); + gc_enable(sc); + } else { + x = car(sc->code); + sc->code = cadr(sc->code); + } + if (!is_symbol(x)) { + Error_0(sc,"variable is not a symbol"); + } + s_save(sc,OP_DEF1, sc->NIL, x); + s_thread_to(sc,OP_EVAL); + + CASE(OP_DEF1): { /* define */ + pointer *sslot; + x = find_slot_spec_in_env(sc, sc->envir, sc->code, 0, &sslot); + if (x != sc->NIL) { + set_slot_in_env(sc, x, sc->value); + } else { + new_slot_spec_in_env(sc, sc->code, sc->value, sslot); + } + s_return(sc,sc->code); + } + + CASE(OP_DEFP): /* defined? */ + x=sc->envir; + if(cdr(sc->args)!=sc->NIL) { + x=cadr(sc->args); + } + s_retbool(find_slot_in_env(sc,x,car(sc->args),1)!=sc->NIL); + + CASE(OP_SET0): /* set! */ + if(is_immutable(car(sc->code))) + Error_1(sc,"set!: unable to alter immutable variable",car(sc->code)); + s_save(sc,OP_SET1, sc->NIL, car(sc->code)); + sc->code = cadr(sc->code); + s_thread_to(sc,OP_EVAL); + + CASE(OP_SET1): /* set! */ + y=find_slot_in_env(sc,sc->envir,sc->code,1); + if (y != sc->NIL) { + set_slot_in_env(sc, y, sc->value); + s_return(sc,sc->value); + } else { + Error_1(sc, "set!: unbound variable", sc->code); + } + + + CASE(OP_BEGIN): /* begin */ + { + int last; + + if (!is_pair(sc->code)) { + s_return(sc,sc->code); + } + + last = cdr(sc->code) == sc->NIL; + if (!last) { + s_save(sc,OP_BEGIN, sc->NIL, cdr(sc->code)); + } + sc->code = car(sc->code); + if (! last) + /* This is not the end of the list. This is not a tail + * position. */ + s_clear_flag(sc, TAIL_CONTEXT); + s_thread_to(sc,OP_EVAL); + } + + CASE(OP_IF0): /* if */ + s_save(sc,OP_IF1, sc->NIL, cdr(sc->code)); + sc->code = car(sc->code); + s_clear_flag(sc, TAIL_CONTEXT); + s_thread_to(sc,OP_EVAL); + + CASE(OP_IF1): /* if */ + if (is_true(sc->value)) + sc->code = car(sc->code); + else + sc->code = cadr(sc->code); /* (if #f 1) ==> () because + * car(sc->NIL) = sc->NIL */ + s_thread_to(sc,OP_EVAL); + + CASE(OP_LET0): /* let */ + sc->args = sc->NIL; + sc->value = sc->code; + sc->code = is_symbol(car(sc->code)) ? cadr(sc->code) : car(sc->code); + s_thread_to(sc,OP_LET1); + + CASE(OP_LET1): /* let (calculate parameters) */ + gc_disable(sc, 1 + (is_pair(sc->code) ? gc_reservations (s_save) : 0)); + sc->args = cons(sc, sc->value, sc->args); + if (is_pair(sc->code)) { /* continue */ + if (!is_pair(car(sc->code)) || !is_pair(cdar(sc->code))) { + gc_enable(sc); + Error_1(sc, "Bad syntax of binding spec in let", + car(sc->code)); + } + s_save(sc,OP_LET1, sc->args, cdr(sc->code)); + gc_enable(sc); + sc->code = cadar(sc->code); + sc->args = sc->NIL; + s_clear_flag(sc, TAIL_CONTEXT); + s_thread_to(sc,OP_EVAL); + } else { /* end */ + gc_enable(sc); + sc->args = reverse_in_place(sc, sc->NIL, sc->args); + sc->code = car(sc->args); + sc->args = cdr(sc->args); + s_thread_to(sc,OP_LET2); + } + + CASE(OP_LET2): /* let */ + new_frame_in_env(sc, sc->envir); + for (x = is_symbol(car(sc->code)) ? cadr(sc->code) : car(sc->code), y = sc->args; + y != sc->NIL; x = cdr(x), y = cdr(y)) { + new_slot_in_env(sc, caar(x), car(y)); + } + if (is_symbol(car(sc->code))) { /* named let */ + for (x = cadr(sc->code), sc->args = sc->NIL; x != sc->NIL; x = cdr(x)) { + if (!is_pair(x)) + Error_1(sc, "Bad syntax of binding in let", x); + if (!is_list(sc, car(x))) + Error_1(sc, "Bad syntax of binding in let", car(x)); + gc_disable(sc, 1); + sc->args = cons(sc, caar(x), sc->args); + gc_enable(sc); + } + gc_disable(sc, 2 + gc_reservations (new_slot_in_env)); + x = mk_closure(sc, cons(sc, reverse_in_place(sc, sc->NIL, sc->args), cddr(sc->code)), sc->envir); + new_slot_in_env(sc, car(sc->code), x); + gc_enable(sc); + sc->code = cddr(sc->code); + sc->args = sc->NIL; + } else { + sc->code = cdr(sc->code); + sc->args = sc->NIL; + } + s_thread_to(sc,OP_BEGIN); + + CASE(OP_LET0AST): /* let* */ + if (car(sc->code) == sc->NIL) { + new_frame_in_env(sc, sc->envir); + sc->code = cdr(sc->code); + s_thread_to(sc,OP_BEGIN); + } + if(!is_pair(car(sc->code)) || !is_pair(caar(sc->code)) || !is_pair(cdaar(sc->code))) { + Error_1(sc, "Bad syntax of binding spec in let*", car(sc->code)); + } + s_save(sc,OP_LET1AST, cdr(sc->code), car(sc->code)); + sc->code = cadaar(sc->code); + s_clear_flag(sc, TAIL_CONTEXT); + s_thread_to(sc,OP_EVAL); + + CASE(OP_LET1AST): /* let* (make new frame) */ + new_frame_in_env(sc, sc->envir); + s_thread_to(sc,OP_LET2AST); + + CASE(OP_LET2AST): /* let* (calculate parameters) */ + new_slot_in_env(sc, caar(sc->code), sc->value); + sc->code = cdr(sc->code); + if (is_pair(sc->code)) { /* continue */ + s_save(sc,OP_LET2AST, sc->args, sc->code); + sc->code = cadar(sc->code); + sc->args = sc->NIL; + s_clear_flag(sc, TAIL_CONTEXT); + s_thread_to(sc,OP_EVAL); + } else { /* end */ + sc->code = sc->args; + sc->args = sc->NIL; + s_thread_to(sc,OP_BEGIN); + } + + CASE(OP_LET0REC): /* letrec */ + new_frame_in_env(sc, sc->envir); + sc->args = sc->NIL; + sc->value = sc->code; + sc->code = car(sc->code); + s_thread_to(sc,OP_LET1REC); + + CASE(OP_LET1REC): /* letrec (calculate parameters) */ + gc_disable(sc, 1); + sc->args = cons(sc, sc->value, sc->args); + gc_enable(sc); + if (is_pair(sc->code)) { /* continue */ + if (!is_pair(car(sc->code)) || !is_pair(cdar(sc->code))) { + Error_1(sc, "Bad syntax of binding spec in letrec", + car(sc->code)); + } + s_save(sc,OP_LET1REC, sc->args, cdr(sc->code)); + sc->code = cadar(sc->code); + sc->args = sc->NIL; + s_clear_flag(sc, TAIL_CONTEXT); + s_thread_to(sc,OP_EVAL); + } else { /* end */ + sc->args = reverse_in_place(sc, sc->NIL, sc->args); + sc->code = car(sc->args); + sc->args = cdr(sc->args); + s_thread_to(sc,OP_LET2REC); + } + + CASE(OP_LET2REC): /* letrec */ + for (x = car(sc->code), y = sc->args; y != sc->NIL; x = cdr(x), y = cdr(y)) { + new_slot_in_env(sc, caar(x), car(y)); + } + sc->code = cdr(sc->code); + sc->args = sc->NIL; + s_thread_to(sc,OP_BEGIN); + + CASE(OP_COND0): /* cond */ + if (!is_pair(sc->code)) { + Error_0(sc,"syntax error in cond"); + } + s_save(sc,OP_COND1, sc->NIL, sc->code); + sc->code = caar(sc->code); + s_clear_flag(sc, TAIL_CONTEXT); + s_thread_to(sc,OP_EVAL); + + CASE(OP_COND1): /* cond */ + if (is_true(sc->value)) { + if ((sc->code = cdar(sc->code)) == sc->NIL) { + s_return(sc,sc->value); + } + if(!sc->code || car(sc->code)==sc->FEED_TO) { + if(!is_pair(cdr(sc->code))) { + Error_0(sc,"syntax error in cond"); + } + gc_disable(sc, 4); + x=cons(sc, sc->QUOTE, cons(sc, sc->value, sc->NIL)); + sc->code=cons(sc,cadr(sc->code),cons(sc,x,sc->NIL)); + gc_enable(sc); + s_thread_to(sc,OP_EVAL); + } + s_thread_to(sc,OP_BEGIN); + } else { + if ((sc->code = cdr(sc->code)) == sc->NIL) { + s_return(sc,sc->NIL); + } else { + s_save(sc,OP_COND1, sc->NIL, sc->code); + sc->code = caar(sc->code); + s_clear_flag(sc, TAIL_CONTEXT); + s_thread_to(sc,OP_EVAL); + } + } + + CASE(OP_DELAY): /* delay */ + gc_disable(sc, 2); + x = mk_closure(sc, cons(sc, sc->NIL, sc->code), sc->envir); + typeflag(x)=T_PROMISE; + s_return_enable_gc(sc,x); + + CASE(OP_AND0): /* and */ + if (sc->code == sc->NIL) { + s_return(sc,sc->T); + } + s_save(sc,OP_AND1, sc->NIL, cdr(sc->code)); + if (cdr(sc->code) != sc->NIL) + s_clear_flag(sc, TAIL_CONTEXT); + sc->code = car(sc->code); + s_thread_to(sc,OP_EVAL); + + CASE(OP_AND1): /* and */ + if (is_false(sc->value)) { + s_return(sc,sc->value); + } else if (sc->code == sc->NIL) { + s_return(sc,sc->value); + } else { + s_save(sc,OP_AND1, sc->NIL, cdr(sc->code)); + if (cdr(sc->code) != sc->NIL) + s_clear_flag(sc, TAIL_CONTEXT); + sc->code = car(sc->code); + s_thread_to(sc,OP_EVAL); + } + + CASE(OP_OR0): /* or */ + if (sc->code == sc->NIL) { + s_return(sc,sc->F); + } + s_save(sc,OP_OR1, sc->NIL, cdr(sc->code)); + if (cdr(sc->code) != sc->NIL) + s_clear_flag(sc, TAIL_CONTEXT); + sc->code = car(sc->code); + s_thread_to(sc,OP_EVAL); + + CASE(OP_OR1): /* or */ + if (is_true(sc->value)) { + s_return(sc,sc->value); + } else if (sc->code == sc->NIL) { + s_return(sc,sc->value); + } else { + s_save(sc,OP_OR1, sc->NIL, cdr(sc->code)); + if (cdr(sc->code) != sc->NIL) + s_clear_flag(sc, TAIL_CONTEXT); + sc->code = car(sc->code); + s_thread_to(sc,OP_EVAL); + } + + CASE(OP_C0STREAM): /* cons-stream */ + s_save(sc,OP_C1STREAM, sc->NIL, cdr(sc->code)); + sc->code = car(sc->code); + s_thread_to(sc,OP_EVAL); + + CASE(OP_C1STREAM): /* cons-stream */ + sc->args = sc->value; /* save sc->value to register sc->args for gc */ + gc_disable(sc, 3); + x = mk_closure(sc, cons(sc, sc->NIL, sc->code), sc->envir); + typeflag(x)=T_PROMISE; + s_return_enable_gc(sc, cons(sc, sc->args, x)); + + CASE(OP_MACRO0): /* macro */ + if (is_pair(car(sc->code))) { + x = caar(sc->code); + gc_disable(sc, 2); + sc->code = cons(sc, sc->LAMBDA, cons(sc, cdar(sc->code), cdr(sc->code))); + gc_enable(sc); + } else { + x = car(sc->code); + sc->code = cadr(sc->code); + } + if (!is_symbol(x)) { + Error_0(sc,"variable is not a symbol"); + } + s_save(sc,OP_MACRO1, sc->NIL, x); + s_thread_to(sc,OP_EVAL); + + CASE(OP_MACRO1): { /* macro */ + pointer *sslot; + typeflag(sc->value) = T_MACRO; + x = find_slot_spec_in_env(sc, sc->envir, sc->code, 0, &sslot); + if (x != sc->NIL) { + set_slot_in_env(sc, x, sc->value); + } else { + new_slot_spec_in_env(sc, sc->code, sc->value, sslot); + } + s_return(sc,sc->code); + } + + CASE(OP_CASE0): /* case */ + s_save(sc,OP_CASE1, sc->NIL, cdr(sc->code)); + sc->code = car(sc->code); + s_clear_flag(sc, TAIL_CONTEXT); + s_thread_to(sc,OP_EVAL); + + CASE(OP_CASE1): /* case */ + for (x = sc->code; x != sc->NIL; x = cdr(x)) { + if (!is_pair(y = caar(x))) { + break; + } + for ( ; y != sc->NIL; y = cdr(y)) { + if (eqv(car(y), sc->value)) { + break; + } + } + if (y != sc->NIL) { + break; + } + } + if (x != sc->NIL) { + if (is_pair(caar(x))) { + sc->code = cdar(x); + s_thread_to(sc,OP_BEGIN); + } else {/* else */ + s_save(sc,OP_CASE2, sc->NIL, cdar(x)); + sc->code = caar(x); + s_thread_to(sc,OP_EVAL); + } + } else { + s_return(sc,sc->NIL); + } + + CASE(OP_CASE2): /* case */ + if (is_true(sc->value)) { + s_thread_to(sc,OP_BEGIN); + } else { + s_return(sc,sc->NIL); + } + + CASE(OP_PAPPLY): /* apply */ + sc->code = car(sc->args); + sc->args = list_star(sc,cdr(sc->args)); + /*sc->args = cadr(sc->args);*/ + s_thread_to(sc,OP_APPLY); + + CASE(OP_PEVAL): /* eval */ + if(cdr(sc->args)!=sc->NIL) { + sc->envir=cadr(sc->args); + } + sc->code = car(sc->args); + s_thread_to(sc,OP_EVAL); + + CASE(OP_CONTINUATION): /* call-with-current-continuation */ + sc->code = car(sc->args); + gc_disable(sc, 2); + sc->args = cons(sc, mk_continuation(sc, sc->dump), sc->NIL); + gc_enable(sc); + s_thread_to(sc,OP_APPLY); + +#if USE_MATH + CASE(OP_INEX2EX): /* inexact->exact */ + x=car(sc->args); + if(num_is_integer(x)) { + s_return(sc,x); + } else if(modf(rvalue_unchecked(x),&dd)==0.0) { + s_return(sc,mk_integer(sc,ivalue(x))); + } else { + Error_1(sc, "inexact->exact: not integral", x); + } + + CASE(OP_EXP): + x=car(sc->args); + s_return(sc, mk_real(sc, exp(rvalue(x)))); + + CASE(OP_LOG): + x=car(sc->args); + s_return(sc, mk_real(sc, log(rvalue(x)))); + + CASE(OP_SIN): + x=car(sc->args); + s_return(sc, mk_real(sc, sin(rvalue(x)))); + + CASE(OP_COS): + x=car(sc->args); + s_return(sc, mk_real(sc, cos(rvalue(x)))); + + CASE(OP_TAN): + x=car(sc->args); + s_return(sc, mk_real(sc, tan(rvalue(x)))); + + CASE(OP_ASIN): + x=car(sc->args); + s_return(sc, mk_real(sc, asin(rvalue(x)))); + + CASE(OP_ACOS): + x=car(sc->args); + s_return(sc, mk_real(sc, acos(rvalue(x)))); + + CASE(OP_ATAN): + x=car(sc->args); + if(cdr(sc->args)==sc->NIL) { + s_return(sc, mk_real(sc, atan(rvalue(x)))); + } else { + pointer y=cadr(sc->args); + s_return(sc, mk_real(sc, atan2(rvalue(x),rvalue(y)))); + } + + CASE(OP_SQRT): + x=car(sc->args); + s_return(sc, mk_real(sc, sqrt(rvalue(x)))); + + CASE(OP_EXPT): { + double result; + int real_result=1; + pointer y=cadr(sc->args); + x=car(sc->args); + if (num_is_integer(x) && num_is_integer(y)) + real_result=0; + /* This 'if' is an R5RS compatibility fix. */ + /* NOTE: Remove this 'if' fix for R6RS. */ + if (rvalue(x) == 0 && rvalue(y) < 0) { + result = 0.0; + } else { + result = pow(rvalue(x),rvalue(y)); + } + /* Before returning integer result make sure we can. */ + /* If the test fails, result is too big for integer. */ + if (!real_result) + { + long result_as_long = (long)result; + if (result != (double)result_as_long) + real_result = 1; + } + if (real_result) { + s_return(sc, mk_real(sc, result)); + } else { + s_return(sc, mk_integer(sc, result)); + } + } + + CASE(OP_FLOOR): + x=car(sc->args); + s_return(sc, mk_real(sc, floor(rvalue(x)))); + + CASE(OP_CEILING): + x=car(sc->args); + s_return(sc, mk_real(sc, ceil(rvalue(x)))); + + CASE(OP_TRUNCATE ): { + double rvalue_of_x ; + x=car(sc->args); + rvalue_of_x = rvalue(x) ; + if (rvalue_of_x > 0) { + s_return(sc, mk_real(sc, floor(rvalue_of_x))); + } else { + s_return(sc, mk_real(sc, ceil(rvalue_of_x))); + } + } + + CASE(OP_ROUND): + x=car(sc->args); + if (num_is_integer(x)) + s_return(sc, x); + s_return(sc, mk_real(sc, round_per_R5RS(rvalue(x)))); +#endif + + CASE(OP_ADD): /* + */ + v=num_zero; + for (x = sc->args; x != sc->NIL; x = cdr(x)) { + v=num_add(v,nvalue(car(x))); + } + gc_disable(sc, 1); + s_return_enable_gc(sc, mk_number(sc, v)); + + CASE(OP_MUL): /* * */ + v=num_one; + for (x = sc->args; x != sc->NIL; x = cdr(x)) { + v=num_mul(v,nvalue(car(x))); + } + gc_disable(sc, 1); + s_return_enable_gc(sc, mk_number(sc, v)); + + CASE(OP_SUB): /* - */ + if(cdr(sc->args)==sc->NIL) { + x=sc->args; + v=num_zero; + } else { + x = cdr(sc->args); + v = nvalue(car(sc->args)); + } + for (; x != sc->NIL; x = cdr(x)) { + v=num_sub(v,nvalue(car(x))); + } + gc_disable(sc, 1); + s_return_enable_gc(sc, mk_number(sc, v)); + + CASE(OP_DIV): /* / */ + if(cdr(sc->args)==sc->NIL) { + x=sc->args; + v=num_one; + } else { + x = cdr(sc->args); + v = nvalue(car(sc->args)); + } + for (; x != sc->NIL; x = cdr(x)) { + if (!is_zero_double(rvalue(car(x)))) + v=num_div(v,nvalue(car(x))); + else { + Error_0(sc,"/: division by zero"); + } + } + gc_disable(sc, 1); + s_return_enable_gc(sc, mk_number(sc, v)); + + CASE(OP_INTDIV): /* quotient */ + if(cdr(sc->args)==sc->NIL) { + x=sc->args; + v=num_one; + } else { + x = cdr(sc->args); + v = nvalue(car(sc->args)); + } + for (; x != sc->NIL; x = cdr(x)) { + if (ivalue(car(x)) != 0) + v=num_intdiv(v,nvalue(car(x))); + else { + Error_0(sc,"quotient: division by zero"); + } + } + gc_disable(sc, 1); + s_return_enable_gc(sc, mk_number(sc, v)); + + CASE(OP_REM): /* remainder */ + v = nvalue(car(sc->args)); + if (ivalue(cadr(sc->args)) != 0) + v=num_rem(v,nvalue(cadr(sc->args))); + else { + Error_0(sc,"remainder: division by zero"); + } + gc_disable(sc, 1); + s_return_enable_gc(sc, mk_number(sc, v)); + + CASE(OP_MOD): /* modulo */ + v = nvalue(car(sc->args)); + if (ivalue(cadr(sc->args)) != 0) + v=num_mod(v,nvalue(cadr(sc->args))); + else { + Error_0(sc,"modulo: division by zero"); + } + gc_disable(sc, 1); + s_return_enable_gc(sc, mk_number(sc, v)); + + CASE(OP_CAR): /* car */ + s_return(sc,caar(sc->args)); + + CASE(OP_CDR): /* cdr */ + s_return(sc,cdar(sc->args)); + + CASE(OP_CONS): /* cons */ + cdr(sc->args) = cadr(sc->args); + s_return(sc,sc->args); + + CASE(OP_SETCAR): /* set-car! */ + if(!is_immutable(car(sc->args))) { + caar(sc->args) = cadr(sc->args); + s_return(sc,car(sc->args)); + } else { + Error_0(sc,"set-car!: unable to alter immutable pair"); + } + + CASE(OP_SETCDR): /* set-cdr! */ + if(!is_immutable(car(sc->args))) { + cdar(sc->args) = cadr(sc->args); + s_return(sc,car(sc->args)); + } else { + Error_0(sc,"set-cdr!: unable to alter immutable pair"); + } + + CASE(OP_CHAR2INT): { /* char->integer */ + char c; + c=(char)ivalue(car(sc->args)); + gc_disable(sc, 1); + s_return_enable_gc(sc, mk_integer(sc, (unsigned char) c)); + } + + CASE(OP_INT2CHAR): { /* integer->char */ + unsigned char c; + c=(unsigned char)ivalue(car(sc->args)); + gc_disable(sc, 1); + s_return_enable_gc(sc, mk_character(sc, (char) c)); + } + + CASE(OP_CHARUPCASE): { + unsigned char c; + c=(unsigned char)ivalue(car(sc->args)); + c=toupper(c); + gc_disable(sc, 1); + s_return_enable_gc(sc, mk_character(sc, (char) c)); + } + + CASE(OP_CHARDNCASE): { + unsigned char c; + c=(unsigned char)ivalue(car(sc->args)); + c=tolower(c); + gc_disable(sc, 1); + s_return_enable_gc(sc, mk_character(sc, (char) c)); + } + + CASE(OP_STR2SYM): /* string->symbol */ + gc_disable(sc, gc_reservations (mk_symbol)); + s_return_enable_gc(sc, mk_symbol(sc, strvalue(car(sc->args)))); + + CASE(OP_STR2ATOM): /* string->atom */ { + char *s=strvalue(car(sc->args)); + long pf = 0; + if(cdr(sc->args)!=sc->NIL) { + /* we know cadr(sc->args) is a natural number */ + /* see if it is 2, 8, 10, or 16, or error */ + pf = ivalue_unchecked(cadr(sc->args)); + if(pf == 16 || pf == 10 || pf == 8 || pf == 2) { + /* base is OK */ + } + else { + pf = -1; + } + } + if (pf < 0) { + Error_1(sc, "string->atom: bad base", cadr(sc->args)); + } else if(*s=='#') /* no use of base! */ { + s_return(sc, mk_sharp_const(sc, s+1)); + } else { + if (pf == 0 || pf == 10) { + s_return(sc, mk_atom(sc, s)); + } + else { + char *ep; + long iv = strtol(s,&ep,(int )pf); + if (*ep == 0) { + s_return(sc, mk_integer(sc, iv)); + } + else { + s_return(sc, sc->F); + } + } + } + } + + CASE(OP_SYM2STR): /* symbol->string */ + gc_disable(sc, 1); + x=mk_string(sc,symname(car(sc->args))); + setimmutable(x); + s_return_enable_gc(sc, x); + + CASE(OP_ATOM2STR): /* atom->string */ { + long pf = 0; + x=car(sc->args); + if(cdr(sc->args)!=sc->NIL) { + /* we know cadr(sc->args) is a natural number */ + /* see if it is 2, 8, 10, or 16, or error */ + pf = ivalue_unchecked(cadr(sc->args)); + if(is_number(x) && (pf == 16 || pf == 10 || pf == 8 || pf == 2)) { + /* base is OK */ + } + else { + pf = -1; + } + } + if (pf < 0) { + Error_1(sc, "atom->string: bad base", cadr(sc->args)); + } else if(is_number(x) || is_character(x) || is_string(x) || is_symbol(x)) { + char *p; + int len; + atom2str(sc,x,(int )pf,&p,&len); + gc_disable(sc, 1); + s_return_enable_gc(sc, mk_counted_string(sc, p, len)); + } else { + Error_1(sc, "atom->string: not an atom", x); + } + } + + CASE(OP_MKSTRING): { /* make-string */ + int fill=' '; + int len; + + len=ivalue(car(sc->args)); + + if(cdr(sc->args)!=sc->NIL) { + fill=charvalue(cadr(sc->args)); + } + gc_disable(sc, 1); + s_return_enable_gc(sc, mk_empty_string(sc, len, (char) fill)); + } + + CASE(OP_STRLEN): /* string-length */ + gc_disable(sc, 1); + s_return_enable_gc(sc, mk_integer(sc, strlength(car(sc->args)))); + + CASE(OP_STRREF): { /* string-ref */ + char *str; + int index; + + str=strvalue(car(sc->args)); + + index=ivalue(cadr(sc->args)); + + if(index>=strlength(car(sc->args))) { + Error_1(sc, "string-ref: out of bounds", cadr(sc->args)); + } + + gc_disable(sc, 1); + s_return_enable_gc(sc, + mk_character(sc, ((unsigned char*) str)[index])); + } + + CASE(OP_STRSET): { /* string-set! */ + char *str; + int index; + int c; + + if(is_immutable(car(sc->args))) { + Error_1(sc, "string-set!: unable to alter immutable string", + car(sc->args)); + } + str=strvalue(car(sc->args)); + + index=ivalue(cadr(sc->args)); + if(index>=strlength(car(sc->args))) { + Error_1(sc, "string-set!: out of bounds", cadr(sc->args)); + } + + c=charvalue(caddr(sc->args)); + + str[index]=(char)c; + s_return(sc,car(sc->args)); + } + + CASE(OP_STRAPPEND): { /* string-append */ + /* in 1.29 string-append was in Scheme in init.scm but was too slow */ + int len = 0; + pointer newstr; + char *pos; + + /* compute needed length for new string */ + for (x = sc->args; x != sc->NIL; x = cdr(x)) { + len += strlength(car(x)); + } + gc_disable(sc, 1); + newstr = mk_empty_string(sc, len, ' '); + /* store the contents of the argument strings into the new string */ + for (pos = strvalue(newstr), x = sc->args; x != sc->NIL; + pos += strlength(car(x)), x = cdr(x)) { + memcpy(pos, strvalue(car(x)), strlength(car(x))); + } + s_return_enable_gc(sc, newstr); + } + + CASE(OP_SUBSTR): { /* substring */ + char *str; + int index0; + int index1; + + str=strvalue(car(sc->args)); + + index0=ivalue(cadr(sc->args)); + + if(index0>strlength(car(sc->args))) { + Error_1(sc, "substring: start out of bounds", cadr(sc->args)); + } + + if(cddr(sc->args)!=sc->NIL) { + index1=ivalue(caddr(sc->args)); + if(index1>strlength(car(sc->args)) || index1<index0) { + Error_1(sc, "substring: end out of bounds", caddr(sc->args)); + } + } else { + index1=strlength(car(sc->args)); + } + + gc_disable(sc, 1); + s_return_enable_gc(sc, mk_counted_string(sc, str + index0, index1 - index0)); + } + + CASE(OP_VECTOR): { /* vector */ + int i; + pointer vec; + int len=list_length(sc,sc->args); + if(len<0) { + Error_1(sc, "vector: not a proper list", sc->args); + } + vec=mk_vector(sc,len); + if(sc->no_memory) { s_return(sc, sc->sink); } + for (x = sc->args, i = 0; is_pair(x); x = cdr(x), i++) { + set_vector_elem(vec,i,car(x)); + } + s_return(sc,vec); + } + + CASE(OP_MKVECTOR): { /* make-vector */ + pointer fill=sc->NIL; + int len; + pointer vec; + + len=ivalue(car(sc->args)); + + if(cdr(sc->args)!=sc->NIL) { + fill=cadr(sc->args); + } + vec=mk_vector(sc,len); + if(sc->no_memory) { s_return(sc, sc->sink); } + if(fill!=sc->NIL) { + fill_vector(vec,fill); + } + s_return(sc,vec); + } + + CASE(OP_VECLEN): /* vector-length */ + gc_disable(sc, 1); + s_return_enable_gc(sc, mk_integer(sc, vector_length(car(sc->args)))); + + CASE(OP_VECREF): { /* vector-ref */ + int index; + + index=ivalue(cadr(sc->args)); + + if(index >= vector_length(car(sc->args))) { + Error_1(sc, "vector-ref: out of bounds", cadr(sc->args)); + } + + s_return(sc,vector_elem(car(sc->args),index)); + } + + CASE(OP_VECSET): { /* vector-set! */ + int index; + + if(is_immutable(car(sc->args))) { + Error_1(sc, "vector-set!: unable to alter immutable vector", + car(sc->args)); + } + + index=ivalue(cadr(sc->args)); + if(index >= vector_length(car(sc->args))) { + Error_1(sc, "vector-set!: out of bounds", cadr(sc->args)); + } + + set_vector_elem(car(sc->args),index,caddr(sc->args)); + s_return(sc,car(sc->args)); + } + + CASE(OP_NOT): /* not */ + s_retbool(is_false(car(sc->args))); + CASE(OP_BOOLP): /* boolean? */ + s_retbool(car(sc->args) == sc->F || car(sc->args) == sc->T); + CASE(OP_EOFOBJP): /* boolean? */ + s_retbool(car(sc->args) == sc->EOF_OBJ); + CASE(OP_NULLP): /* null? */ + s_retbool(car(sc->args) == sc->NIL); + CASE(OP_NUMEQ): /* = */ + /* Fallthrough. */ + CASE(OP_LESS): /* < */ + /* Fallthrough. */ + CASE(OP_GRE): /* > */ + /* Fallthrough. */ + CASE(OP_LEQ): /* <= */ + /* Fallthrough. */ + CASE(OP_GEQ): /* >= */ + switch(op) { + case OP_NUMEQ: comp_func=num_eq; break; + case OP_LESS: comp_func=num_lt; break; + case OP_GRE: comp_func=num_gt; break; + case OP_LEQ: comp_func=num_le; break; + case OP_GEQ: comp_func=num_ge; break; + default: assert (! "reached"); + } + x=sc->args; + v=nvalue(car(x)); + x=cdr(x); + + for (; x != sc->NIL; x = cdr(x)) { + if(!comp_func(v,nvalue(car(x)))) { + s_retbool(0); + } + v=nvalue(car(x)); + } + s_retbool(1); + CASE(OP_SYMBOLP): /* symbol? */ + s_retbool(is_symbol(car(sc->args))); + CASE(OP_NUMBERP): /* number? */ + s_retbool(is_number(car(sc->args))); + CASE(OP_STRINGP): /* string? */ + s_retbool(is_string(car(sc->args))); + CASE(OP_INTEGERP): /* integer? */ + s_retbool(is_integer(car(sc->args))); + CASE(OP_REALP): /* real? */ + s_retbool(is_number(car(sc->args))); /* All numbers are real */ + CASE(OP_CHARP): /* char? */ + s_retbool(is_character(car(sc->args))); +#if USE_CHAR_CLASSIFIERS + CASE(OP_CHARAP): /* char-alphabetic? */ + s_retbool(Cisalpha(ivalue(car(sc->args)))); + CASE(OP_CHARNP): /* char-numeric? */ + s_retbool(Cisdigit(ivalue(car(sc->args)))); + CASE(OP_CHARWP): /* char-whitespace? */ + s_retbool(Cisspace(ivalue(car(sc->args)))); + CASE(OP_CHARUP): /* char-upper-case? */ + s_retbool(Cisupper(ivalue(car(sc->args)))); + CASE(OP_CHARLP): /* char-lower-case? */ + s_retbool(Cislower(ivalue(car(sc->args)))); +#endif + CASE(OP_PORTP): /* port? */ + s_retbool(is_port(car(sc->args))); + CASE(OP_INPORTP): /* input-port? */ + s_retbool(is_inport(car(sc->args))); + CASE(OP_OUTPORTP): /* output-port? */ + s_retbool(is_outport(car(sc->args))); + CASE(OP_PROCP): /* procedure? */ + /*-- + * continuation should be procedure by the example + * (call-with-current-continuation procedure?) ==> #t + * in R^3 report sec. 6.9 + */ + s_retbool(is_proc(car(sc->args)) || is_closure(car(sc->args)) + || is_continuation(car(sc->args)) || is_foreign(car(sc->args))); + CASE(OP_PAIRP): /* pair? */ + s_retbool(is_pair(car(sc->args))); + CASE(OP_LISTP): /* list? */ + s_retbool(list_length(sc,car(sc->args)) >= 0); + + CASE(OP_ENVP): /* environment? */ + s_retbool(is_environment(car(sc->args))); + CASE(OP_VECTORP): /* vector? */ + s_retbool(is_vector(car(sc->args))); + CASE(OP_EQ): /* eq? */ + s_retbool(car(sc->args) == cadr(sc->args)); + CASE(OP_EQV): /* eqv? */ + s_retbool(eqv(car(sc->args), cadr(sc->args))); + + CASE(OP_FORCE): /* force */ + sc->code = car(sc->args); + if (is_promise(sc->code)) { + /* Should change type to closure here */ + s_save(sc, OP_SAVE_FORCED, sc->NIL, sc->code); + sc->args = sc->NIL; + s_thread_to(sc,OP_APPLY); + } else { + s_return(sc,sc->code); + } + + CASE(OP_SAVE_FORCED): /* Save forced value replacing promise */ + copy_value(sc, sc->code, sc->value); + s_return(sc,sc->value); + + CASE(OP_WRITE): /* write */ + /* Fallthrough. */ + CASE(OP_DISPLAY): /* display */ + /* Fallthrough. */ + CASE(OP_WRITE_CHAR): /* write-char */ + if(is_pair(cdr(sc->args))) { + if(cadr(sc->args)!=sc->outport) { + x=cons(sc,sc->outport,sc->NIL); + s_save(sc,OP_SET_OUTPORT, x, sc->NIL); + sc->outport=cadr(sc->args); + } + } + sc->args = car(sc->args); + if(op==OP_WRITE) { + sc->print_flag = 1; + } else { + sc->print_flag = 0; + } + s_thread_to(sc,OP_P0LIST); + + CASE(OP_NEWLINE): /* newline */ + if(is_pair(sc->args)) { + if(car(sc->args)!=sc->outport) { + x=cons(sc,sc->outport,sc->NIL); + s_save(sc,OP_SET_OUTPORT, x, sc->NIL); + sc->outport=car(sc->args); + } + } + putstr(sc, "\n"); + s_return(sc,sc->T); + + CASE(OP_ERR0): /* error */ + sc->retcode=-1; + if (!is_string(car(sc->args))) { + sc->args=cons(sc,mk_string(sc," -- "),sc->args); + setimmutable(car(sc->args)); + } + putstr(sc, "Error: "); + putstr(sc, strvalue(car(sc->args))); + sc->args = cdr(sc->args); + s_thread_to(sc,OP_ERR1); + + CASE(OP_ERR1): /* error */ + putstr(sc, " "); + if (sc->args != sc->NIL) { + s_save(sc,OP_ERR1, cdr(sc->args), sc->NIL); + sc->args = car(sc->args); + sc->print_flag = 1; + s_thread_to(sc,OP_P0LIST); + } else { + putstr(sc, "\n"); + if(sc->interactive_repl) { + s_thread_to(sc,OP_T0LVL); + } else { + return; + } + } + + CASE(OP_REVERSE): /* reverse */ + s_return(sc,reverse(sc, sc->NIL, car(sc->args))); + + CASE(OP_REVERSE_IN_PLACE): /* reverse! */ + s_return(sc, reverse_in_place(sc, sc->NIL, car(sc->args))); + + CASE(OP_LIST_STAR): /* list* */ + s_return(sc,list_star(sc,sc->args)); + + CASE(OP_APPEND): /* append */ + x = sc->NIL; + y = sc->args; + if (y == x) { + s_return(sc, x); + } + + /* cdr() in the while condition is not a typo. If car() */ + /* is used (append '() 'a) will return the wrong result.*/ + while (cdr(y) != sc->NIL) { + x = revappend(sc, x, car(y)); + y = cdr(y); + if (x == sc->F) { + Error_0(sc, "non-list argument to append"); + } + } + + s_return(sc, reverse_in_place(sc, car(y), x)); + +#if USE_PLIST + CASE(OP_SET_SYMBOL_PROPERTY): /* set-symbol-property! */ + gc_disable(sc, gc_reservations(set_property)); + s_return_enable_gc(sc, + set_property(sc, car(sc->args), + cadr(sc->args), caddr(sc->args))); + + CASE(OP_SYMBOL_PROPERTY): /* symbol-property */ + s_return(sc, get_property(sc, car(sc->args), cadr(sc->args))); +#endif /* USE_PLIST */ + + CASE(OP_TAG_VALUE): { /* not exposed */ + /* This tags sc->value with car(sc->args). Useful to tag + * results of opcode evaluations. */ + pointer a, b, c; + free_cons(sc, sc->args, &a, &b); + free_cons(sc, b, &b, &c); + assert(c == sc->NIL); + s_return(sc, mk_tagged_value(sc, sc->value, a, b)); + } + + CASE(OP_MK_TAGGED): /* make-tagged-value */ + if (is_vector(car(sc->args))) + Error_0(sc, "cannot tag vector"); + s_return(sc, mk_tagged_value(sc, car(sc->args), + car(cadr(sc->args)), + cdr(cadr(sc->args)))); + + CASE(OP_GET_TAG): /* get-tag */ + s_return(sc, get_tag(sc, car(sc->args))); + + CASE(OP_QUIT): /* quit */ + if(is_pair(sc->args)) { + sc->retcode=ivalue(car(sc->args)); + } + return; + + CASE(OP_GC): /* gc */ + gc(sc, sc->NIL, sc->NIL); + s_return(sc,sc->T); + + CASE(OP_GCVERB): /* gc-verbose */ + { int was = sc->gc_verbose; + + sc->gc_verbose = (car(sc->args) != sc->F); + s_retbool(was); + } + + CASE(OP_NEWSEGMENT): /* new-segment */ + if (!is_pair(sc->args) || !is_number(car(sc->args))) { + Error_0(sc,"new-segment: argument must be a number"); + } + alloc_cellseg(sc, (int) ivalue(car(sc->args))); + s_return(sc,sc->T); + + CASE(OP_OBLIST): /* oblist */ + s_return(sc, oblist_all_symbols(sc)); + + CASE(OP_CURR_INPORT): /* current-input-port */ + s_return(sc,sc->inport); + + CASE(OP_CURR_OUTPORT): /* current-output-port */ + s_return(sc,sc->outport); + + CASE(OP_OPEN_INFILE): /* open-input-file */ + /* Fallthrough. */ + CASE(OP_OPEN_OUTFILE): /* open-output-file */ + /* Fallthrough. */ + CASE(OP_OPEN_INOUTFILE): /* open-input-output-file */ { + int prop=0; + pointer p; + switch(op) { + case OP_OPEN_INFILE: prop=port_input; break; + case OP_OPEN_OUTFILE: prop=port_output; break; + case OP_OPEN_INOUTFILE: prop=port_input|port_output; break; + default: assert (! "reached"); + } + p=port_from_filename(sc,strvalue(car(sc->args)),prop); + if(p==sc->NIL) { + s_return(sc,sc->F); + } + s_return(sc,p); + break; + } + +#if USE_STRING_PORTS + CASE(OP_OPEN_INSTRING): /* open-input-string */ + /* Fallthrough. */ + CASE(OP_OPEN_INOUTSTRING): /* open-input-output-string */ { + int prop=0; + pointer p; + switch(op) { + case OP_OPEN_INSTRING: prop=port_input; break; + case OP_OPEN_INOUTSTRING: prop=port_input|port_output; break; + default: assert (! "reached"); + } + p=port_from_string(sc, strvalue(car(sc->args)), + strvalue(car(sc->args))+strlength(car(sc->args)), prop); + if(p==sc->NIL) { + s_return(sc,sc->F); + } + s_return(sc,p); + } + CASE(OP_OPEN_OUTSTRING): /* open-output-string */ { + pointer p; + if(car(sc->args)==sc->NIL) { + p=port_from_scratch(sc); + if(p==sc->NIL) { + s_return(sc,sc->F); + } + } else { + p=port_from_string(sc, strvalue(car(sc->args)), + strvalue(car(sc->args))+strlength(car(sc->args)), + port_output); + if(p==sc->NIL) { + s_return(sc,sc->F); + } + } + s_return(sc,p); + } + CASE(OP_GET_OUTSTRING): /* get-output-string */ { + port *p; + + if ((p=car(sc->args)->_object._port)->kind&port_string) { + gc_disable(sc, 1); + s_return_enable_gc( + sc, + mk_counted_string(sc, + p->rep.string.start, + p->rep.string.curr - p->rep.string.start)); + } + s_return(sc,sc->F); + } +#endif + + CASE(OP_CLOSE_INPORT): /* close-input-port */ + port_close(sc,car(sc->args),port_input); + s_return(sc,sc->T); + + CASE(OP_CLOSE_OUTPORT): /* close-output-port */ + port_close(sc,car(sc->args),port_output); + s_return(sc,sc->T); + + CASE(OP_INT_ENV): /* interaction-environment */ + s_return(sc,sc->global_env); + + CASE(OP_CURR_ENV): /* current-environment */ + s_return(sc,sc->envir); + + + /* ========== reading part ========== */ + CASE(OP_READ): + if(!is_pair(sc->args)) { + s_thread_to(sc,OP_READ_INTERNAL); + } + if(!is_inport(car(sc->args))) { + Error_1(sc, "read: not an input port", car(sc->args)); + } + if(car(sc->args)==sc->inport) { + s_thread_to(sc,OP_READ_INTERNAL); + } + x=sc->inport; + sc->inport=car(sc->args); + x=cons(sc,x,sc->NIL); + s_save(sc,OP_SET_INPORT, x, sc->NIL); + s_thread_to(sc,OP_READ_INTERNAL); + + CASE(OP_READ_CHAR): /* read-char */ + /* Fallthrough. */ + CASE(OP_PEEK_CHAR): /* peek-char */ { + int c; + if(is_pair(sc->args)) { + if(car(sc->args)!=sc->inport) { + x=sc->inport; + x=cons(sc,x,sc->NIL); + s_save(sc,OP_SET_INPORT, x, sc->NIL); + sc->inport=car(sc->args); + } + } + c=inchar(sc); + if(c==EOF) { + s_return(sc,sc->EOF_OBJ); + } + if(op==OP_PEEK_CHAR) { + backchar(sc,c); + } + s_return(sc,mk_character(sc,c)); + } + + CASE(OP_CHAR_READY): /* char-ready? */ { + pointer p=sc->inport; + int res; + if(is_pair(sc->args)) { + p=car(sc->args); + } + res=p->_object._port->kind&port_string; + s_retbool(res); + } + + CASE(OP_SET_INPORT): /* set-input-port */ + sc->inport=car(sc->args); + s_return(sc,sc->value); + + CASE(OP_SET_OUTPORT): /* set-output-port */ + sc->outport=car(sc->args); + s_return(sc,sc->value); + + CASE(OP_RDSEXPR): + switch (sc->tok) { + case TOK_EOF: + s_return(sc,sc->EOF_OBJ); + /* NOTREACHED */ + case TOK_VEC: + s_save(sc,OP_RDVEC,sc->NIL,sc->NIL); + /* fall through */ + case TOK_LPAREN: + sc->tok = token(sc); + if (sc->tok == TOK_RPAREN) { + s_return(sc,sc->NIL); + } else if (sc->tok == TOK_DOT) { + Error_0(sc,"syntax error: illegal dot expression"); + } else { +#if SHOW_ERROR_LINE + pointer filename; + pointer lineno; +#endif + sc->nesting_stack[sc->file_i]++; +#if SHOW_ERROR_LINE + filename = sc->load_stack[sc->file_i].filename; + lineno = sc->load_stack[sc->file_i].curr_line; + + s_save(sc, OP_TAG_VALUE, + cons(sc, filename, cons(sc, lineno, sc->NIL)), + sc->NIL); +#endif + s_save(sc,OP_RDLIST, sc->NIL, sc->NIL); + s_thread_to(sc,OP_RDSEXPR); + } + case TOK_QUOTE: + s_save(sc,OP_RDQUOTE, sc->NIL, sc->NIL); + sc->tok = token(sc); + s_thread_to(sc,OP_RDSEXPR); + case TOK_BQUOTE: + sc->tok = token(sc); + if(sc->tok==TOK_VEC) { + s_save(sc,OP_RDQQUOTEVEC, sc->NIL, sc->NIL); + sc->tok=TOK_LPAREN; + s_thread_to(sc,OP_RDSEXPR); + } else { + s_save(sc,OP_RDQQUOTE, sc->NIL, sc->NIL); + } + s_thread_to(sc,OP_RDSEXPR); + case TOK_COMMA: + s_save(sc,OP_RDUNQUOTE, sc->NIL, sc->NIL); + sc->tok = token(sc); + s_thread_to(sc,OP_RDSEXPR); + case TOK_ATMARK: + s_save(sc,OP_RDUQTSP, sc->NIL, sc->NIL); + sc->tok = token(sc); + s_thread_to(sc,OP_RDSEXPR); + case TOK_ATOM: + s_return(sc,mk_atom(sc, readstr_upto(sc, DELIMITERS))); + case TOK_DQUOTE: + x=readstrexp(sc); + if(x==sc->F) { + Error_0(sc,"Error reading string"); + } + setimmutable(x); + s_return(sc,x); + case TOK_SHARP: { + pointer f=find_slot_in_env(sc,sc->envir,sc->SHARP_HOOK,1); + if(f==sc->NIL) { + Error_0(sc,"undefined sharp expression"); + } else { + sc->code=cons(sc,slot_value_in_env(f),sc->NIL); + s_thread_to(sc,OP_EVAL); + } + } + case TOK_SHARP_CONST: + if ((x = mk_sharp_const(sc, readstr_upto(sc, DELIMITERS))) == sc->NIL) { + Error_0(sc,"undefined sharp expression"); + } else { + s_return(sc,x); + } + default: + Error_0(sc,"syntax error: illegal token"); + } + break; + + CASE(OP_RDLIST): { + gc_disable(sc, 1); + sc->args = cons(sc, sc->value, sc->args); + gc_enable(sc); + sc->tok = token(sc); + if (sc->tok == TOK_EOF) + { s_return(sc,sc->EOF_OBJ); } + else if (sc->tok == TOK_RPAREN) { + int c = inchar(sc); + if (c != '\n') + backchar(sc,c); + else + port_increment_current_line(sc, &sc->load_stack[sc->file_i], 1); + sc->nesting_stack[sc->file_i]--; + s_return(sc,reverse_in_place(sc, sc->NIL, sc->args)); + } else if (sc->tok == TOK_DOT) { + s_save(sc,OP_RDDOT, sc->args, sc->NIL); + sc->tok = token(sc); + s_thread_to(sc,OP_RDSEXPR); + } else { + s_save(sc,OP_RDLIST, sc->args, sc->NIL);; + s_thread_to(sc,OP_RDSEXPR); + } + } + + CASE(OP_RDDOT): + if (token(sc) != TOK_RPAREN) { + Error_0(sc,"syntax error: illegal dot expression"); + } else { + sc->nesting_stack[sc->file_i]--; + s_return(sc,reverse_in_place(sc, sc->value, sc->args)); + } + + CASE(OP_RDQUOTE): + gc_disable(sc, 2); + s_return_enable_gc(sc, cons(sc, sc->QUOTE, + cons(sc, sc->value, sc->NIL))); + + CASE(OP_RDQQUOTE): + gc_disable(sc, 2); + s_return_enable_gc(sc, cons(sc, sc->QQUOTE, + cons(sc, sc->value, sc->NIL))); + + CASE(OP_RDQQUOTEVEC): + gc_disable(sc, 5 + 2 * gc_reservations (mk_symbol)); + s_return_enable_gc(sc,cons(sc, mk_symbol(sc,"apply"), + cons(sc, mk_symbol(sc,"vector"), + cons(sc,cons(sc, sc->QQUOTE, + cons(sc,sc->value,sc->NIL)), + sc->NIL)))); + + CASE(OP_RDUNQUOTE): + gc_disable(sc, 2); + s_return_enable_gc(sc, cons(sc, sc->UNQUOTE, + cons(sc, sc->value, sc->NIL))); + + CASE(OP_RDUQTSP): + gc_disable(sc, 2); + s_return_enable_gc(sc, cons(sc, sc->UNQUOTESP, + cons(sc, sc->value, sc->NIL))); + + CASE(OP_RDVEC): + /*sc->code=cons(sc,mk_proc(sc,OP_VECTOR),sc->value); + s_thread_to(sc,OP_EVAL); Cannot be quoted*/ + /*x=cons(sc,mk_proc(sc,OP_VECTOR),sc->value); + s_return(sc,x); Cannot be part of pairs*/ + /*sc->code=mk_proc(sc,OP_VECTOR); + sc->args=sc->value; + s_thread_to(sc,OP_APPLY);*/ + sc->args=sc->value; + s_thread_to(sc,OP_VECTOR); + + /* ========== printing part ========== */ + CASE(OP_P0LIST): + if(is_vector(sc->args)) { + putstr(sc,"#("); + sc->args=cons(sc,sc->args,mk_integer(sc,0)); + s_thread_to(sc,OP_PVECFROM); + } else if(is_environment(sc->args)) { + putstr(sc,"#<ENVIRONMENT>"); + s_return(sc,sc->T); + } else if (!is_pair(sc->args)) { + printatom(sc, sc->args, sc->print_flag); + s_return(sc,sc->T); + } else if (car(sc->args) == sc->QUOTE && ok_abbrev(cdr(sc->args))) { + putstr(sc, "'"); + sc->args = cadr(sc->args); + s_thread_to(sc,OP_P0LIST); + } else if (car(sc->args) == sc->QQUOTE && ok_abbrev(cdr(sc->args))) { + putstr(sc, "`"); + sc->args = cadr(sc->args); + s_thread_to(sc,OP_P0LIST); + } else if (car(sc->args) == sc->UNQUOTE && ok_abbrev(cdr(sc->args))) { + putstr(sc, ","); + sc->args = cadr(sc->args); + s_thread_to(sc,OP_P0LIST); + } else if (car(sc->args) == sc->UNQUOTESP && ok_abbrev(cdr(sc->args))) { + putstr(sc, ",@"); + sc->args = cadr(sc->args); + s_thread_to(sc,OP_P0LIST); + } else { + putstr(sc, "("); + s_save(sc,OP_P1LIST, cdr(sc->args), sc->NIL); + sc->args = car(sc->args); + s_thread_to(sc,OP_P0LIST); + } + + CASE(OP_P1LIST): + if (is_pair(sc->args)) { + s_save(sc,OP_P1LIST, cdr(sc->args), sc->NIL); + putstr(sc, " "); + sc->args = car(sc->args); + s_thread_to(sc,OP_P0LIST); + } else if(is_vector(sc->args)) { + s_save(sc,OP_P1LIST,sc->NIL,sc->NIL); + putstr(sc, " . "); + s_thread_to(sc,OP_P0LIST); + } else { + if (sc->args != sc->NIL) { + putstr(sc, " . "); + printatom(sc, sc->args, sc->print_flag); + } + putstr(sc, ")"); + s_return(sc,sc->T); + } + CASE(OP_PVECFROM): { + int i=ivalue_unchecked(cdr(sc->args)); + pointer vec=car(sc->args); + int len = vector_length(vec); + if(i==len) { + putstr(sc,")"); + s_return(sc,sc->T); + } else { + pointer elem=vector_elem(vec,i); + cdr(sc->args) = mk_integer(sc, i + 1); + s_save(sc,OP_PVECFROM, sc->args, sc->NIL); + sc->args=elem; + if (i > 0) + putstr(sc," "); + s_thread_to(sc,OP_P0LIST); + } + } + + CASE(OP_LIST_LENGTH): { /* length */ /* a.k */ + long l = list_length(sc, car(sc->args)); + if(l<0) { + Error_1(sc, "length: not a list", car(sc->args)); + } + gc_disable(sc, 1); + s_return_enable_gc(sc, mk_integer(sc, l)); + } + CASE(OP_ASSQ): /* assq */ /* a.k */ + x = car(sc->args); + for (y = cadr(sc->args); is_pair(y); y = cdr(y)) { + if (!is_pair(car(y))) { + Error_0(sc,"unable to handle non pair element"); + } + if (x == caar(y)) + break; + } + if (is_pair(y)) { + s_return(sc,car(y)); + } else { + s_return(sc,sc->F); + } + + + CASE(OP_GET_CLOSURE): /* get-closure-code */ /* a.k */ + sc->args = car(sc->args); + if (sc->args == sc->NIL) { + s_return(sc,sc->F); + } else if (is_closure(sc->args)) { + gc_disable(sc, 1); + s_return_enable_gc(sc, cons(sc, sc->LAMBDA, + closure_code(sc->value))); + } else if (is_macro(sc->args)) { + gc_disable(sc, 1); + s_return_enable_gc(sc, cons(sc, sc->LAMBDA, + closure_code(sc->value))); + } else { + s_return(sc,sc->F); + } + CASE(OP_CLOSUREP): /* closure? */ + /* + * Note, macro object is also a closure. + * Therefore, (closure? <#MACRO>) ==> #t + */ + s_retbool(is_closure(car(sc->args))); + CASE(OP_MACROP): /* macro? */ + s_retbool(is_macro(car(sc->args))); + CASE(OP_VM_HISTORY): /* *vm-history* */ + s_return(sc, history_flatten(sc)); + default: + snprintf(sc->strbuff,STRBUFFSIZE,"%d: illegal operator", op); + Error_0(sc,sc->strbuff); + } + } +} + +#if GPGRT_GCC_VERSION >= 80000 +# pragma GCC diagnostic pop +#endif + + +typedef int (*test_predicate)(pointer); + +static int is_any(pointer p) { + (void)p; + return 1; +} + +static int is_nonneg(pointer p) { + return ivalue(p)>=0 && is_integer(p); +} + +/* Correspond carefully with following defines! */ +static const struct { + test_predicate fct; + const char *kind; +} tests[]={ + {0,0}, /* unused */ + {is_any, 0}, + {is_string, "string"}, + {is_symbol, "symbol"}, + {is_port, "port"}, + {is_inport,"input port"}, + {is_outport,"output port"}, + {is_environment, "environment"}, + {is_pair, "pair"}, + {0, "pair or '()"}, + {is_character, "character"}, + {is_vector, "vector"}, + {is_number, "number"}, + {is_integer, "integer"}, + {is_nonneg, "non-negative integer"} +}; + +#define TST_NONE 0 +#define TST_ANY "\001" +#define TST_STRING "\002" +#define TST_SYMBOL "\003" +#define TST_PORT "\004" +#define TST_INPORT "\005" +#define TST_OUTPORT "\006" +#define TST_ENVIRONMENT "\007" +#define TST_PAIR "\010" +#define TST_LIST "\011" +#define TST_CHAR "\012" +#define TST_VECTOR "\013" +#define TST_NUMBER "\014" +#define TST_INTEGER "\015" +#define TST_NATURAL "\016" + +#define INF_ARG 0xff + +static const struct op_code_info dispatch_table[]= { +#define _OP_DEF(A,B,C,D,OP) {{A},B,C,{D}}, +#include "opdefines.h" +#undef _OP_DEF + {{0},0,0,{0}}, +}; + +static const char *procname(pointer x) { + int n=procnum(x); + const char *name=dispatch_table[n].name; + if (name[0] == 0) { + name="ILLEGAL!"; + } + return name; +} + +static int +check_arguments (scheme *sc, const struct op_code_info *pcd, char *msg, size_t msg_size) +{ + int ok = 1; + int n = list_length(sc, sc->args); + + /* Check number of arguments */ + if (n < pcd->min_arity) { + ok = 0; + snprintf(msg, msg_size, "%s: needs%s %d argument(s)", + pcd->name, + pcd->min_arity == pcd->max_arity ? "" : " at least", + pcd->min_arity); + } + if (ok && n>pcd->max_arity) { + ok = 0; + snprintf(msg, msg_size, "%s: needs%s %d argument(s)", + pcd->name, + pcd->min_arity == pcd->max_arity ? "" : " at most", + pcd->max_arity); + } + if (ok) { + if (pcd->arg_tests_encoding[0] != 0) { + int i = 0; + int j; + const char *t = pcd->arg_tests_encoding; + pointer arglist = sc->args; + + do { + pointer arg = car(arglist); + j = (int)t[0]; + if (j == TST_LIST[0]) { + if (arg != sc->NIL && !is_pair(arg)) break; + } else { + if (!tests[j].fct(arg)) break; + } + + if (t[1] != 0 && i < sizeof pcd->arg_tests_encoding) { + /* last test is replicated as necessary */ + t++; + } + arglist = cdr(arglist); + i++; + } while (i < n); + + if (i < n) { + ok = 0; + snprintf(msg, msg_size, "%s: argument %d must be: %s, got: %s", + pcd->name, + i + 1, + tests[j].kind, + type_to_string(type(car(arglist)))); + } + } + } + + return ok; +} + +/* ========== Initialization of internal keywords ========== */ + +/* Symbols representing syntax are tagged with (OP . '()). */ +static void assign_syntax(scheme *sc, enum scheme_opcodes op, char *name) { + pointer x, y; + pointer *slot; + + x = oblist_find_by_name(sc, name, &slot); + assert (x == sc->NIL); + + x = immutable_cons(sc, mk_string(sc, name), sc->NIL); + typeflag(x) = T_SYMBOL | T_SYNTAX; + setimmutable(car(x)); + y = mk_tagged_value(sc, x, mk_integer(sc, op), sc->NIL); + free_cell(sc, x); + setimmutable(get_tag(sc, y)); + *slot = immutable_cons(sc, y, *slot); +} + +/* Returns the opcode for the syntax represented by P. */ +static int syntaxnum(scheme *sc, pointer p) { + int op = ivalue_unchecked(car(get_tag(sc, p))); + assert (op < OP_MAXDEFINED); + return op; +} + +static void assign_proc(scheme *sc, enum scheme_opcodes op, const char *name) { + pointer x, y; + + x = mk_symbol(sc, name); + y = mk_proc(sc,op); + new_slot_in_env(sc, x, y); +} + +static pointer mk_proc(scheme *sc, enum scheme_opcodes op) { + pointer y; + + y = get_cell(sc, sc->NIL, sc->NIL); + typeflag(y) = (T_PROC | T_ATOM); + ivalue_unchecked(y) = (long) op; + set_num_integer(y); + return y; +} + +/* initialization of TinyScheme */ +#if USE_INTERFACE +INTERFACE static pointer s_cons(scheme *sc, pointer a, pointer b) { + return cons(sc,a,b); +} +INTERFACE static pointer s_immutable_cons(scheme *sc, pointer a, pointer b) { + return immutable_cons(sc,a,b); +} + +static const struct scheme_interface vtbl = { + scheme_define, + s_cons, + s_immutable_cons, + reserve_cells, + mk_integer, + mk_real, + mk_symbol, + gensym, + mk_string, + mk_counted_string, + mk_character, + mk_vector, + mk_foreign_func, + mk_foreign_object, + get_foreign_object_vtable, + get_foreign_object_data, + putstr, + putcharacter, + + is_string, + string_value, + is_number, + nvalue, + ivalue, + rvalue, + is_integer, + is_real, + is_character, + charvalue, + is_list, + is_vector, + list_length, + ivalue, + fill_vector, + vector_elem, + set_vector_elem, + is_port, + is_pair, + pair_car, + pair_cdr, + set_car, + set_cdr, + + is_symbol, + symname, + + is_syntax, + is_proc, + is_foreign, + syntaxname, + is_closure, + is_macro, + closure_code, + closure_env, + + is_continuation, + is_promise, + is_environment, + is_immutable, + setimmutable, + + scheme_load_file, + scheme_load_string, + port_from_file +}; +#endif + +scheme *scheme_init_new() { + scheme *sc=(scheme*)malloc(sizeof(scheme)); + if(!scheme_init(sc)) { + free(sc); + return 0; + } else { + return sc; + } +} + +scheme *scheme_init_new_custom_alloc(func_alloc malloc, func_dealloc free) { + scheme *sc=(scheme*)malloc(sizeof(scheme)); + if(!scheme_init_custom_alloc(sc,malloc,free)) { + free(sc); + return 0; + } else { + return sc; + } +} + + +int scheme_init(scheme *sc) { + return scheme_init_custom_alloc(sc,malloc,free); +} + +int scheme_init_custom_alloc(scheme *sc, func_alloc malloc, func_dealloc free) { + int i, n=sizeof(dispatch_table)/sizeof(dispatch_table[0]); + pointer x; + +#if USE_INTERFACE + sc->vptr=&vtbl; +#endif + sc->gensym_cnt=0; + sc->malloc=malloc; + sc->free=free; + sc->sink = &sc->_sink; + sc->NIL = &sc->_NIL; + sc->T = &sc->_HASHT; + sc->F = &sc->_HASHF; + sc->EOF_OBJ=&sc->_EOF_OBJ; + + sc->free_cell = &sc->_NIL; + sc->fcells = 0; + sc->inhibit_gc = GC_ENABLED; + sc->reserved_cells = 0; +#ifndef NDEBUG + sc->reserved_lineno = 0; +#endif + sc->no_memory=0; + sc->inport=sc->NIL; + sc->outport=sc->NIL; + sc->save_inport=sc->NIL; + sc->loadport=sc->NIL; + sc->nesting=0; + memset (sc->nesting_stack, 0, sizeof sc->nesting_stack); + sc->interactive_repl=0; + sc->strbuff = sc->malloc(STRBUFFSIZE); + if (sc->strbuff == 0) { + sc->no_memory=1; + return 0; + } + sc->strbuff_size = STRBUFFSIZE; + + sc->cell_segments = NULL; + if (alloc_cellseg(sc,FIRST_CELLSEGS) != FIRST_CELLSEGS) { + sc->no_memory=1; + return 0; + } + sc->gc_verbose = 0; + dump_stack_initialize(sc); + sc->code = sc->NIL; + sc->tracing=0; + sc->flags = 0; + + /* init sc->NIL */ + typeflag(sc->NIL) = (T_NIL | T_ATOM | MARK); + car(sc->NIL) = cdr(sc->NIL) = sc->NIL; + /* init T */ + typeflag(sc->T) = (T_BOOLEAN | T_ATOM | MARK); + car(sc->T) = cdr(sc->T) = sc->T; + /* init F */ + typeflag(sc->F) = (T_BOOLEAN | T_ATOM | MARK); + car(sc->F) = cdr(sc->F) = sc->F; + /* init EOF_OBJ */ + typeflag(sc->EOF_OBJ) = (T_EOF_OBJ | T_ATOM | MARK); + car(sc->EOF_OBJ) = cdr(sc->EOF_OBJ) = sc->EOF_OBJ; + /* init sink */ + typeflag(sc->sink) = (T_SINK | T_PAIR | MARK); + car(sc->sink) = cdr(sc->sink) = sc->NIL; + /* init c_nest */ + sc->c_nest = sc->NIL; + + sc->oblist = oblist_initial_value(sc); + /* init global_env */ + new_frame_in_env(sc, sc->NIL); + sc->global_env = sc->envir; + /* init else */ + x = mk_symbol(sc,"else"); + new_slot_in_env(sc, x, sc->T); + + assign_syntax(sc, OP_LAMBDA, "lambda"); + assign_syntax(sc, OP_QUOTE, "quote"); + assign_syntax(sc, OP_DEF0, "define"); + assign_syntax(sc, OP_IF0, "if"); + assign_syntax(sc, OP_BEGIN, "begin"); + assign_syntax(sc, OP_SET0, "set!"); + assign_syntax(sc, OP_LET0, "let"); + assign_syntax(sc, OP_LET0AST, "let*"); + assign_syntax(sc, OP_LET0REC, "letrec"); + assign_syntax(sc, OP_COND0, "cond"); + assign_syntax(sc, OP_DELAY, "delay"); + assign_syntax(sc, OP_AND0, "and"); + assign_syntax(sc, OP_OR0, "or"); + assign_syntax(sc, OP_C0STREAM, "cons-stream"); + assign_syntax(sc, OP_MACRO0, "macro"); + assign_syntax(sc, OP_CASE0, "case"); + + for(i=0; i<n; i++) { + if (dispatch_table[i].name[0] != 0) { + assign_proc(sc, (enum scheme_opcodes)i, dispatch_table[i].name); + } + } + + history_init(sc, 8, 8); + + /* initialization of global pointers to special symbols */ + sc->LAMBDA = mk_symbol(sc, "lambda"); + sc->QUOTE = mk_symbol(sc, "quote"); + sc->QQUOTE = mk_symbol(sc, "quasiquote"); + sc->UNQUOTE = mk_symbol(sc, "unquote"); + sc->UNQUOTESP = mk_symbol(sc, "unquote-splicing"); + sc->FEED_TO = mk_symbol(sc, "=>"); + sc->COLON_HOOK = mk_symbol(sc,"*colon-hook*"); + sc->ERROR_HOOK = mk_symbol(sc, "*error-hook*"); + sc->SHARP_HOOK = mk_symbol(sc, "*sharp-hook*"); +#if USE_COMPILE_HOOK + sc->COMPILE_HOOK = mk_symbol(sc, "*compile-hook*"); +#endif + + return !sc->no_memory; +} + +void scheme_set_input_port_file(scheme *sc, FILE *fin) { + sc->inport=port_from_file(sc,fin,port_input); +} + +void scheme_set_input_port_string(scheme *sc, char *start, char *past_the_end) { + sc->inport=port_from_string(sc,start,past_the_end,port_input); +} + +void scheme_set_output_port_file(scheme *sc, FILE *fout) { + sc->outport=port_from_file(sc,fout,port_output); +} + +void scheme_set_output_port_string(scheme *sc, char *start, char *past_the_end) { + sc->outport=port_from_string(sc,start,past_the_end,port_output); +} + +void scheme_set_external_data(scheme *sc, void *p) { + sc->ext_data=p; +} + +void scheme_deinit(scheme *sc) { + struct cell_segment *s; + int i; + + sc->oblist=sc->NIL; + sc->global_env=sc->NIL; + dump_stack_free(sc); + sc->envir=sc->NIL; + sc->code=sc->NIL; + history_free(sc); + sc->args=sc->NIL; + sc->value=sc->NIL; + if(is_port(sc->inport)) { + typeflag(sc->inport) = T_ATOM; + } + sc->inport=sc->NIL; + sc->outport=sc->NIL; + if(is_port(sc->save_inport)) { + typeflag(sc->save_inport) = T_ATOM; + } + sc->save_inport=sc->NIL; + if(is_port(sc->loadport)) { + typeflag(sc->loadport) = T_ATOM; + } + sc->loadport=sc->NIL; + + for(i=0; i<=sc->file_i; i++) { + port_clear_location(sc, &sc->load_stack[i]); + } + + sc->gc_verbose=0; + gc(sc,sc->NIL,sc->NIL); + + for (s = sc->cell_segments; s; s = _dealloc_cellseg(sc, s)) { + /* nop */ + } + sc->free(sc->strbuff); +} + +void scheme_load_file(scheme *sc, FILE *fin) +{ scheme_load_named_file(sc,fin,0); } + +void scheme_load_named_file(scheme *sc, FILE *fin, const char *filename) { + dump_stack_reset(sc); + sc->envir = sc->global_env; + sc->file_i=0; + sc->load_stack[0].kind=port_input|port_file; + sc->load_stack[0].rep.stdio.file=fin; + sc->loadport=mk_port(sc,sc->load_stack); + sc->retcode=0; + if(fin==stdin) { + sc->interactive_repl=1; + } + + port_init_location(sc, &sc->load_stack[0], + (fin != stdin && filename) + ? mk_string(sc, filename) + : NULL); + + sc->inport=sc->loadport; + sc->args = mk_integer(sc,sc->file_i); + Eval_Cycle(sc, OP_T0LVL); + typeflag(sc->loadport)=T_ATOM; + if(sc->retcode==0) { + sc->retcode=sc->nesting!=0; + } + + port_clear_location(sc, &sc->load_stack[0]); +} + +void scheme_load_string(scheme *sc, const char *cmd) { + scheme_load_memory(sc, cmd, strlen(cmd), NULL); +} + +void scheme_load_memory(scheme *sc, const char *buf, size_t len, const char *filename) { + dump_stack_reset(sc); + sc->envir = sc->global_env; + sc->file_i=0; + sc->load_stack[0].kind=port_input|port_string; + sc->load_stack[0].rep.string.start = (char *) buf; /* This func respects const */ + sc->load_stack[0].rep.string.past_the_end = (char *) buf + len; + sc->load_stack[0].rep.string.curr = (char *) buf; + port_init_location(sc, &sc->load_stack[0], filename ? mk_string(sc, filename) : NULL); + sc->loadport=mk_port(sc,sc->load_stack); + sc->retcode=0; + sc->interactive_repl=0; + sc->inport=sc->loadport; + sc->args = mk_integer(sc,sc->file_i); + Eval_Cycle(sc, OP_T0LVL); + typeflag(sc->loadport)=T_ATOM; + if(sc->retcode==0) { + sc->retcode=sc->nesting!=0; + } + + port_clear_location(sc, &sc->load_stack[0]); +} + +void scheme_define(scheme *sc, pointer envir, pointer symbol, pointer value) { + pointer x; + pointer *sslot; + x = find_slot_spec_in_env(sc, envir, symbol, 0, &sslot); + if (x != sc->NIL) { + set_slot_in_env(sc, x, value); + } else { + new_slot_spec_in_env(sc, symbol, value, sslot); + } +} + +#if !STANDALONE +void scheme_register_foreign_func(scheme * sc, scheme_registerable * sr) +{ + scheme_define(sc, + sc->global_env, + mk_symbol(sc,sr->name), + mk_foreign_func(sc, sr->f)); +} + +void scheme_register_foreign_func_list(scheme * sc, + scheme_registerable * list, + int count) +{ + int i; + for(i = 0; i < count; i++) + { + scheme_register_foreign_func(sc, list + i); + } +} + +pointer scheme_apply0(scheme *sc, const char *procname) +{ return scheme_eval(sc, cons(sc,mk_symbol(sc,procname),sc->NIL)); } + +void save_from_C_call(scheme *sc) +{ + pointer saved_data = + cons(sc, + car(sc->sink), + cons(sc, + sc->envir, + sc->dump)); + /* Push */ + sc->c_nest = cons(sc, saved_data, sc->c_nest); + /* Truncate the dump stack so TS will return here when done, not + directly resume pre-C-call operations. */ + dump_stack_reset(sc); +} +void restore_from_C_call(scheme *sc) +{ + car(sc->sink) = caar(sc->c_nest); + sc->envir = cadar(sc->c_nest); + sc->dump = cdr(cdar(sc->c_nest)); + /* Pop */ + sc->c_nest = cdr(sc->c_nest); +} + +/* "func" and "args" are assumed to be already eval'ed. */ +pointer scheme_call(scheme *sc, pointer func, pointer args) +{ + int old_repl = sc->interactive_repl; + sc->interactive_repl = 0; + save_from_C_call(sc); + sc->envir = sc->global_env; + sc->args = args; + sc->code = func; + sc->retcode = 0; + Eval_Cycle(sc, OP_APPLY); + sc->interactive_repl = old_repl; + restore_from_C_call(sc); + return sc->value; +} + +pointer scheme_eval(scheme *sc, pointer obj) +{ + int old_repl = sc->interactive_repl; + sc->interactive_repl = 0; + save_from_C_call(sc); + sc->args = sc->NIL; + sc->code = obj; + sc->retcode = 0; + Eval_Cycle(sc, OP_EVAL); + sc->interactive_repl = old_repl; + restore_from_C_call(sc); + return sc->value; +} + + +#endif + +/* ========== Main ========== */ + +#if STANDALONE + +#if defined(__APPLE__) && !defined (OSX) +int main() +{ + extern MacTS_main(int argc, char **argv); + char** argv; + int argc = ccommand(&argv); + MacTS_main(argc,argv); + return 0; +} +int MacTS_main(int argc, char **argv) { +#else +int main(int argc, char **argv) { +#endif + scheme sc; + FILE *fin; + char *file_name=InitFile; + int retcode; + int isfile=1; + + if(argc==1) { + printf(banner); + } + if(argc==2 && strcmp(argv[1],"-?")==0) { + printf("Usage: tinyscheme -?\n"); + printf("or: tinyscheme [<file1> <file2> ...]\n"); + printf("followed by\n"); + printf(" -1 <file> [<arg1> <arg2> ...]\n"); + printf(" -c <Scheme commands> [<arg1> <arg2> ...]\n"); + printf("assuming that the executable is named tinyscheme.\n"); + printf("Use - as filename for stdin.\n"); + return 1; + } + if(!scheme_init(&sc)) { + fprintf(stderr,"Could not initialize!\n"); + return 2; + } + scheme_set_input_port_file(&sc, stdin); + scheme_set_output_port_file(&sc, stdout); +#if USE_DL + scheme_define(&sc,sc.global_env,mk_symbol(&sc,"load-extension"),mk_foreign_func(&sc, scm_load_ext)); +#endif + argv++; + if(access(file_name,0)!=0) { + char *p=getenv("TINYSCHEMEINIT"); + if(p!=0) { + file_name=p; + } + } + do { + if(strcmp(file_name,"-")==0) { + fin=stdin; + } else if(strcmp(file_name,"-1")==0 || strcmp(file_name,"-c")==0) { + pointer args=sc.NIL; + isfile=file_name[1]=='1'; + file_name=*argv++; + if(strcmp(file_name,"-")==0) { + fin=stdin; + } else if(isfile) { + fin=fopen(file_name,"r"); + } + for(;*argv;argv++) { + pointer value=mk_string(&sc,*argv); + args=cons(&sc,value,args); + } + args=reverse_in_place(&sc,sc.NIL,args); + scheme_define(&sc,sc.global_env,mk_symbol(&sc,"*args*"),args); + + } else { + fin=fopen(file_name,"r"); + } + if(isfile && fin==0) { + fprintf(stderr,"Could not open file %s\n",file_name); + } else { + if(isfile) { + scheme_load_named_file(&sc,fin,file_name); + } else { + scheme_load_string(&sc,file_name); + } + if(!isfile || fin!=stdin) { + if(sc.retcode!=0) { + fprintf(stderr,"Errors encountered reading %s\n",file_name); + } + if(isfile) { + fclose(fin); + } + } + } + file_name=*argv++; + } while(file_name!=0); + if(argc==1) { + scheme_load_named_file(&sc,stdin,0); + } + retcode=sc.retcode; + scheme_deinit(&sc); + + return retcode; +} + +#endif + +/* +Local variables: +c-file-style: "k&r" +End: +*/ |