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-rw-r--r--src/preproc/pic/lex.cpp2039
1 files changed, 2039 insertions, 0 deletions
diff --git a/src/preproc/pic/lex.cpp b/src/preproc/pic/lex.cpp
new file mode 100644
index 0000000..e59801b
--- /dev/null
+++ b/src/preproc/pic/lex.cpp
@@ -0,0 +1,2039 @@
+// -*- C++ -*-
+/* Copyright (C) 1989-2020 Free Software Foundation, Inc.
+ Written by James Clark (jjc@jclark.com)
+
+This file is part of groff.
+
+groff is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+groff is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>. */
+
+#include "pic.h"
+#include "ptable.h"
+#include "object.h"
+#include "pic.hpp"
+
+declare_ptable(char)
+implement_ptable(char)
+
+PTABLE(char) macro_table;
+
+// First character of the range representing $1-$<MAX_ARG>.
+// All of them must be invalid input characters.
+#ifndef IS_EBCDIC_HOST
+#define ARG1 0x80
+#define MAX_ARG 32
+#else
+#define ARG1 0x30
+#define MAX_ARG 16
+#endif
+
+class macro_input : public input {
+ char *s;
+ char *p;
+public:
+ macro_input(const char *);
+ ~macro_input();
+ int get();
+ int peek();
+};
+
+class argument_macro_input : public input {
+ char *s;
+ char *p;
+ char *ap;
+ int argc;
+ char *argv[MAX_ARG];
+public:
+ argument_macro_input(const char *, int, char **);
+ ~argument_macro_input();
+ int get();
+ int peek();
+};
+
+input::input() : next(0)
+{
+}
+
+input::~input()
+{
+}
+
+int input::get_location(const char **, int *)
+{
+ return 0;
+}
+
+file_input::file_input(FILE *f, const char *fn)
+: fp(f), filename(fn), lineno(0), ptr("")
+{
+}
+
+file_input::~file_input()
+{
+ fclose(fp);
+}
+
+int file_input::read_line()
+{
+ for (;;) {
+ line.clear();
+ lineno++;
+ for (;;) {
+ int c = getc(fp);
+ if (c == '\r') {
+ c = getc(fp);
+ if (c != '\n')
+ lex_error("invalid input character code %1", '\r');
+ }
+ if (c == EOF)
+ break;
+ else if (is_invalid_input_char(c))
+ lex_error("invalid input character code %1", c);
+ else {
+ line += char(c);
+ if (c == '\n')
+ break;
+ }
+ }
+ if (line.length() == 0)
+ return 0;
+ if (!(line.length() >= 3 && line[0] == '.' && line[1] == 'P'
+ && (line[2] == 'S' || line[2] == 'E' || line[2] == 'F')
+ && (line.length() == 3 || line[3] == ' ' || line[3] == '\n'
+ || compatible_flag))) {
+ line += '\0';
+ ptr = line.contents();
+ return 1;
+ }
+ }
+}
+
+int file_input::get()
+{
+ if (*ptr != '\0' || read_line())
+ return (unsigned char)*ptr++;
+ else
+ return EOF;
+}
+
+int file_input::peek()
+{
+ if (*ptr != '\0' || read_line())
+ return (unsigned char)*ptr;
+ else
+ return EOF;
+}
+
+int file_input::get_location(const char **fnp, int *lnp)
+{
+ *fnp = filename;
+ *lnp = lineno;
+ return 1;
+}
+
+macro_input::macro_input(const char *str)
+{
+ p = s = strsave(str);
+}
+
+macro_input::~macro_input()
+{
+ free(s);
+}
+
+int macro_input::get()
+{
+ if (p == 0 || *p == '\0')
+ return EOF;
+ else
+ return (unsigned char)*p++;
+}
+
+int macro_input::peek()
+{
+ if (p == 0 || *p == '\0')
+ return EOF;
+ else
+ return (unsigned char)*p;
+}
+
+char *process_body(const char *body)
+{
+ char *s = strsave(body);
+ int j = 0;
+ for (int i = 0; s[i] != '\0'; i++)
+ if (s[i] == '$' && csdigit(s[i + 1])) {
+ int n = 0;
+ int start = i;
+ i++;
+ while (csdigit(s[i]))
+ if (n > MAX_ARG)
+ i++;
+ else
+ n = 10 * n + s[i++] - '0';
+ if (n > MAX_ARG) {
+ string arg;
+ for (int k = start; k < i; k++)
+ arg += s[k];
+ lex_error("invalid macro argument number %1", arg.contents());
+ }
+ else if (n > 0)
+ s[j++] = ARG1 + n - 1;
+ i--;
+ }
+ else
+ s[j++] = s[i];
+ s[j] = '\0';
+ return s;
+}
+
+argument_macro_input::argument_macro_input(const char *body, int ac, char **av)
+: ap(0), argc(ac)
+{
+ for (int i = 0; i < argc; i++)
+ argv[i] = av[i];
+ p = s = process_body(body);
+}
+
+argument_macro_input::~argument_macro_input()
+{
+ for (int i = 0; i < argc; i++)
+ free(argv[i]);
+ free(s);
+}
+
+int argument_macro_input::get()
+{
+ if (ap) {
+ if (*ap != '\0')
+ return (unsigned char)*ap++;
+ ap = 0;
+ }
+ if (p == 0)
+ return EOF;
+ while ((unsigned char)*p >= ARG1
+ && (unsigned char)*p <= ARG1 + MAX_ARG - 1) {
+ int i = (unsigned char)*p++ - ARG1;
+ if (i < argc && argv[i] != 0 && argv[i][0] != '\0') {
+ ap = argv[i];
+ return (unsigned char)*ap++;
+ }
+ }
+ if (*p == '\0')
+ return EOF;
+ return (unsigned char)*p++;
+}
+
+int argument_macro_input::peek()
+{
+ if (ap) {
+ if (*ap != '\0')
+ return (unsigned char)*ap;
+ ap = 0;
+ }
+ if (p == 0)
+ return EOF;
+ while ((unsigned char)*p >= ARG1
+ && (unsigned char)*p <= ARG1 + MAX_ARG - 1) {
+ int i = (unsigned char)*p++ - ARG1;
+ if (i < argc && argv[i] != 0 && argv[i][0] != '\0') {
+ ap = argv[i];
+ return (unsigned char)*ap;
+ }
+ }
+ if (*p == '\0')
+ return EOF;
+ return (unsigned char)*p;
+}
+
+class input_stack {
+ static input *current_input;
+ static int bol_flag;
+public:
+ static void push(input *);
+ static void clear();
+ static int get_char();
+ static int peek_char();
+ static int get_location(const char **fnp, int *lnp);
+ static void push_back(unsigned char c, int was_bol = 0);
+ static int bol();
+};
+
+input *input_stack::current_input = 0;
+int input_stack::bol_flag = 0;
+
+inline int input_stack::bol()
+{
+ return bol_flag;
+}
+
+void input_stack::clear()
+{
+ while (current_input != 0) {
+ input *tem = current_input;
+ current_input = current_input->next;
+ delete tem;
+ }
+ bol_flag = 1;
+}
+
+void input_stack::push(input *in)
+{
+ in->next = current_input;
+ current_input = in;
+}
+
+void lex_init(input *top)
+{
+ input_stack::clear();
+ input_stack::push(top);
+}
+
+void lex_cleanup()
+{
+ while (input_stack::get_char() != EOF)
+ ;
+}
+
+int input_stack::get_char()
+{
+ while (current_input != 0) {
+ int c = current_input->get();
+ if (c != EOF) {
+ bol_flag = c == '\n';
+ return c;
+ }
+ // don't pop the top-level input off the stack
+ if (current_input->next == 0)
+ return EOF;
+ input *tem = current_input;
+ current_input = current_input->next;
+ delete tem;
+ }
+ return EOF;
+}
+
+int input_stack::peek_char()
+{
+ while (current_input != 0) {
+ int c = current_input->peek();
+ if (c != EOF)
+ return c;
+ if (current_input->next == 0)
+ return EOF;
+ input *tem = current_input;
+ current_input = current_input->next;
+ delete tem;
+ }
+ return EOF;
+}
+
+class char_input : public input {
+ int c;
+public:
+ char_input(int);
+ int get();
+ int peek();
+};
+
+char_input::char_input(int n) : c((unsigned char)n)
+{
+}
+
+int char_input::get()
+{
+ int n = c;
+ c = EOF;
+ return n;
+}
+
+int char_input::peek()
+{
+ return c;
+}
+
+void input_stack::push_back(unsigned char c, int was_bol)
+{
+ push(new char_input(c));
+ bol_flag = was_bol;
+}
+
+int input_stack::get_location(const char **fnp, int *lnp)
+{
+ for (input *p = current_input; p; p = p->next)
+ if (p->get_location(fnp, lnp))
+ return 1;
+ return 0;
+}
+
+string context_buffer;
+
+string token_buffer;
+double token_double;
+int token_int;
+
+void interpolate_macro_with_args(const char *body)
+{
+ char *argv[MAX_ARG];
+ int argc = 0;
+ int ignore = 0;
+ int i;
+ for (i = 0; i < MAX_ARG; i++)
+ argv[i] = 0;
+ int level = 0;
+ int c;
+ enum { NORMAL, IN_STRING, IN_STRING_QUOTED } state = NORMAL;
+ do {
+ token_buffer.clear();
+ for (;;) {
+ c = input_stack::get_char();
+ if (c == EOF) {
+ lex_error("end of input while scanning macro arguments");
+ break;
+ }
+ if (state == NORMAL && level == 0 && (c == ',' || c == ')')) {
+ if (token_buffer.length() > 0) {
+ token_buffer += '\0';
+ if (!ignore) {
+ if (argc == MAX_ARG) {
+ lex_warning("only %1 macro arguments supported", MAX_ARG);
+ ignore = 1;
+ }
+ else
+ argv[argc] = strsave(token_buffer.contents());
+ }
+ }
+ // for 'foo()', argc = 0
+ if (argc > 0 || c != ')' || i > 0)
+ if (!ignore)
+ argc++;
+ break;
+ }
+ token_buffer += char(c);
+ switch (state) {
+ case NORMAL:
+ if (c == '"')
+ state = IN_STRING;
+ else if (c == '(')
+ level++;
+ else if (c == ')')
+ level--;
+ break;
+ case IN_STRING:
+ if (c == '"')
+ state = NORMAL;
+ else if (c == '\\')
+ state = IN_STRING_QUOTED;
+ break;
+ case IN_STRING_QUOTED:
+ state = IN_STRING;
+ break;
+ }
+ }
+ } while (c != ')' && c != EOF);
+ input_stack::push(new argument_macro_input(body, argc, argv));
+}
+
+static int docmp(const char *s1, int n1, const char *s2, int n2)
+{
+ if (n1 < n2) {
+ int r = memcmp(s1, s2, n1);
+ return r ? r : -1;
+ }
+ else if (n1 > n2) {
+ int r = memcmp(s1, s2, n2);
+ return r ? r : 1;
+ }
+ else
+ return memcmp(s1, s2, n1);
+}
+
+int lookup_keyword(const char *str, int len)
+{
+ static struct keyword {
+ const char *name;
+ int token;
+ } table[] = {
+ { "Here", HERE },
+ { "above", ABOVE },
+ { "aligned", ALIGNED },
+ { "and", AND },
+ { "arc", ARC },
+ { "arrow", ARROW },
+ { "at", AT },
+ { "atan2", ATAN2 },
+ { "below", BELOW },
+ { "between", BETWEEN },
+ { "bottom", BOTTOM },
+ { "box", BOX },
+ { "by", BY },
+ { "ccw", CCW },
+ { "center", CENTER },
+ { "chop", CHOP },
+ { "circle", CIRCLE },
+ { "color", COLORED },
+ { "colored", COLORED },
+ { "colour", COLORED },
+ { "coloured", COLORED },
+ { "command", COMMAND },
+ { "copy", COPY },
+ { "cos", COS },
+ { "cw", CW },
+ { "dashed", DASHED },
+ { "define", DEFINE },
+ { "diam", DIAMETER },
+ { "diameter", DIAMETER },
+ { "do", DO },
+ { "dotted", DOTTED },
+ { "down", DOWN },
+ { "east", EAST },
+ { "ellipse", ELLIPSE },
+ { "else", ELSE },
+ { "end", END },
+ { "exp", EXP },
+ { "figname", FIGNAME },
+ { "fill", FILL },
+ { "filled", FILL },
+ { "for", FOR },
+ { "from", FROM },
+ { "height", HEIGHT },
+ { "ht", HEIGHT },
+ { "if", IF },
+ { "int", INT },
+ { "invis", INVISIBLE },
+ { "invisible", INVISIBLE },
+ { "last", LAST },
+ { "left", LEFT },
+ { "line", LINE },
+ { "ljust", LJUST },
+ { "log", LOG },
+ { "lower", LOWER },
+ { "max", K_MAX },
+ { "min", K_MIN },
+ { "move", MOVE },
+ { "north", NORTH },
+ { "of", OF },
+ { "outline", OUTLINED },
+ { "outlined", OUTLINED },
+ { "plot", PLOT },
+ { "print", PRINT },
+ { "rad", RADIUS },
+ { "radius", RADIUS },
+ { "rand", RAND },
+ { "reset", RESET },
+ { "right", RIGHT },
+ { "rjust", RJUST },
+ { "same", SAME },
+ { "sh", SH },
+ { "shaded", SHADED },
+ { "sin", SIN },
+ { "solid", SOLID },
+ { "south", SOUTH },
+ { "spline", SPLINE },
+ { "sprintf", SPRINTF },
+ { "sqrt", SQRT },
+ { "srand", SRAND },
+ { "start", START },
+ { "the", THE },
+ { "then", THEN },
+ { "thick", THICKNESS },
+ { "thickness", THICKNESS },
+ { "thru", THRU },
+ { "to", TO },
+ { "top", TOP },
+ { "undef", UNDEF },
+ { "until", UNTIL },
+ { "up", UP },
+ { "upper", UPPER },
+ { "way", WAY },
+ { "west", WEST },
+ { "wid", WIDTH },
+ { "width", WIDTH },
+ { "with", WITH },
+ { "xslanted", XSLANTED },
+ { "yslanted", YSLANTED },
+ };
+
+ const keyword *start = table;
+ const keyword *end = table + sizeof(table)/sizeof(table[0]);
+ while (start < end) {
+ // start <= target < end
+ const keyword *mid = start + (end - start)/2;
+
+ int cmp = docmp(str, len, mid->name, strlen(mid->name));
+ if (cmp == 0)
+ return mid->token;
+ if (cmp < 0)
+ end = mid;
+ else
+ start = mid + 1;
+ }
+ return 0;
+}
+
+int get_token_after_dot(int c)
+{
+ // get_token deals with the case where c is a digit
+ switch (c) {
+ case 'h':
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 't') {
+ input_stack::get_char();
+ context_buffer = ".ht";
+ return DOT_HT;
+ }
+ else if (c == 'e') {
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'i') {
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'g') {
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'h') {
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 't') {
+ input_stack::get_char();
+ context_buffer = ".height";
+ return DOT_HT;
+ }
+ input_stack::push_back('h');
+ }
+ input_stack::push_back('g');
+ }
+ input_stack::push_back('i');
+ }
+ input_stack::push_back('e');
+ }
+ input_stack::push_back('h');
+ return '.';
+ case 'x':
+ input_stack::get_char();
+ context_buffer = ".x";
+ return DOT_X;
+ case 'y':
+ input_stack::get_char();
+ context_buffer = ".y";
+ return DOT_Y;
+ case 'c':
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'e') {
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'n') {
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 't') {
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'e') {
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'r') {
+ input_stack::get_char();
+ context_buffer = ".center";
+ return DOT_C;
+ }
+ input_stack::push_back('e');
+ }
+ input_stack::push_back('t');
+ }
+ input_stack::push_back('n');
+ }
+ input_stack::push_back('e');
+ }
+ context_buffer = ".c";
+ return DOT_C;
+ case 'n':
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'e') {
+ input_stack::get_char();
+ context_buffer = ".ne";
+ return DOT_NE;
+ }
+ else if (c == 'w') {
+ input_stack::get_char();
+ context_buffer = ".nw";
+ return DOT_NW;
+ }
+ else {
+ context_buffer = ".n";
+ return DOT_N;
+ }
+ break;
+ case 'e':
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'n') {
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'd') {
+ input_stack::get_char();
+ context_buffer = ".end";
+ return DOT_END;
+ }
+ input_stack::push_back('n');
+ context_buffer = ".e";
+ return DOT_E;
+ }
+ context_buffer = ".e";
+ return DOT_E;
+ case 'w':
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'i') {
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'd') {
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 't') {
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'h') {
+ input_stack::get_char();
+ context_buffer = ".width";
+ return DOT_WID;
+ }
+ input_stack::push_back('t');
+ }
+ context_buffer = ".wid";
+ return DOT_WID;
+ }
+ input_stack::push_back('i');
+ }
+ context_buffer = ".w";
+ return DOT_W;
+ case 's':
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'e') {
+ input_stack::get_char();
+ context_buffer = ".se";
+ return DOT_SE;
+ }
+ else if (c == 'w') {
+ input_stack::get_char();
+ context_buffer = ".sw";
+ return DOT_SW;
+ }
+ else {
+ if (c == 't') {
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'a') {
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'r') {
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 't') {
+ input_stack::get_char();
+ context_buffer = ".start";
+ return DOT_START;
+ }
+ input_stack::push_back('r');
+ }
+ input_stack::push_back('a');
+ }
+ input_stack::push_back('t');
+ }
+ context_buffer = ".s";
+ return DOT_S;
+ }
+ break;
+ case 't':
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'o') {
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'p') {
+ input_stack::get_char();
+ context_buffer = ".top";
+ return DOT_N;
+ }
+ input_stack::push_back('o');
+ }
+ context_buffer = ".t";
+ return DOT_N;
+ case 'l':
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'e') {
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'f') {
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 't') {
+ input_stack::get_char();
+ context_buffer = ".left";
+ return DOT_W;
+ }
+ input_stack::push_back('f');
+ }
+ input_stack::push_back('e');
+ }
+ context_buffer = ".l";
+ return DOT_W;
+ case 'r':
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'a') {
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'd') {
+ input_stack::get_char();
+ context_buffer = ".rad";
+ return DOT_RAD;
+ }
+ input_stack::push_back('a');
+ }
+ else if (c == 'i') {
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'g') {
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'h') {
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 't') {
+ input_stack::get_char();
+ context_buffer = ".right";
+ return DOT_E;
+ }
+ input_stack::push_back('h');
+ }
+ input_stack::push_back('g');
+ }
+ input_stack::push_back('i');
+ }
+ context_buffer = ".r";
+ return DOT_E;
+ case 'b':
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'o') {
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 't') {
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 't') {
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'o') {
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'm') {
+ input_stack::get_char();
+ context_buffer = ".bottom";
+ return DOT_S;
+ }
+ input_stack::push_back('o');
+ }
+ input_stack::push_back('t');
+ }
+ context_buffer = ".bot";
+ return DOT_S;
+ }
+ input_stack::push_back('o');
+ }
+ context_buffer = ".b";
+ return DOT_S;
+ default:
+ context_buffer = '.';
+ return '.';
+ }
+}
+
+int get_token(int lookup_flag)
+{
+ context_buffer.clear();
+ for (;;) {
+ int n = 0;
+ int bol = input_stack::bol();
+ int c = input_stack::get_char();
+ if (bol && c == command_char) {
+ token_buffer.clear();
+ token_buffer += c;
+ // the newline is not part of the token
+ for (;;) {
+ c = input_stack::peek_char();
+ if (c == EOF || c == '\n')
+ break;
+ input_stack::get_char();
+ token_buffer += char(c);
+ }
+ context_buffer = token_buffer;
+ return COMMAND_LINE;
+ }
+ switch (c) {
+ case EOF:
+ return EOF;
+ case ' ':
+ case '\t':
+ break;
+ case '\\':
+ {
+ int d = input_stack::peek_char();
+ if (d != '\n') {
+ context_buffer = '\\';
+ return '\\';
+ }
+ input_stack::get_char();
+ break;
+ }
+ case '#':
+ do {
+ c = input_stack::get_char();
+ } while (c != '\n' && c != EOF);
+ if (c == '\n')
+ context_buffer = '\n';
+ return c;
+ case '"':
+ context_buffer = '"';
+ token_buffer.clear();
+ for (;;) {
+ c = input_stack::get_char();
+ if (c == '\\') {
+ context_buffer += '\\';
+ c = input_stack::peek_char();
+ if (c == '"') {
+ input_stack::get_char();
+ token_buffer += '"';
+ context_buffer += '"';
+ }
+ else
+ token_buffer += '\\';
+ }
+ else if (c == '\n') {
+ error("newline in string");
+ break;
+ }
+ else if (c == EOF) {
+ error("missing '\"'");
+ break;
+ }
+ else if (c == '"') {
+ context_buffer += '"';
+ break;
+ }
+ else {
+ context_buffer += char(c);
+ token_buffer += char(c);
+ }
+ }
+ return TEXT;
+ case '0':
+ case '1':
+ case '2':
+ case '3':
+ case '4':
+ case '5':
+ case '6':
+ case '7':
+ case '8':
+ case '9':
+ {
+ int overflow = 0;
+ n = 0;
+ for (;;) {
+ if (n > (INT_MAX - 9)/10) {
+ overflow = 1;
+ break;
+ }
+ n *= 10;
+ n += c - '0';
+ context_buffer += char(c);
+ c = input_stack::peek_char();
+ if (c == EOF || !csdigit(c))
+ break;
+ c = input_stack::get_char();
+ }
+ token_double = n;
+ if (overflow) {
+ for (;;) {
+ token_double *= 10.0;
+ token_double += c - '0';
+ context_buffer += char(c);
+ c = input_stack::peek_char();
+ if (c == EOF || !csdigit(c))
+ break;
+ c = input_stack::get_char();
+ }
+ // if somebody asks for 1000000000000th, we will silently
+ // give them INT_MAXth
+ double temp = token_double; // work around gas 1.34/sparc bug
+ if (token_double > INT_MAX)
+ n = INT_MAX;
+ else
+ n = int(temp);
+ }
+ }
+ switch (c) {
+ case 'i':
+ case 'I':
+ context_buffer += char(c);
+ input_stack::get_char();
+ return NUMBER;
+ case '.':
+ {
+ context_buffer += '.';
+ input_stack::get_char();
+ got_dot:
+ double factor = 1.0;
+ for (;;) {
+ c = input_stack::peek_char();
+ if (c == EOF || !csdigit(c))
+ break;
+ input_stack::get_char();
+ context_buffer += char(c);
+ factor /= 10.0;
+ if (c != '0')
+ token_double += factor*(c - '0');
+ }
+ if (c != 'e' && c != 'E') {
+ if (c == 'i' || c == 'I') {
+ context_buffer += char(c);
+ input_stack::get_char();
+ }
+ return NUMBER;
+ }
+ }
+ // fall through
+ case 'e':
+ case 'E':
+ {
+ int echar = c;
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ int sign = '+';
+ if (c == '+' || c == '-') {
+ sign = c;
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == EOF || !csdigit(c)) {
+ input_stack::push_back(sign);
+ input_stack::push_back(echar);
+ return NUMBER;
+ }
+ context_buffer += char(echar);
+ context_buffer += char(sign);
+ }
+ else {
+ if (c == EOF || !csdigit(c)) {
+ input_stack::push_back(echar);
+ return NUMBER;
+ }
+ context_buffer += char(echar);
+ }
+ input_stack::get_char();
+ context_buffer += char(c);
+ n = c - '0';
+ for (;;) {
+ c = input_stack::peek_char();
+ if (c == EOF || !csdigit(c))
+ break;
+ input_stack::get_char();
+ context_buffer += char(c);
+ n = n*10 + (c - '0');
+ }
+ if (sign == '-')
+ n = -n;
+ if (c == 'i' || c == 'I') {
+ context_buffer += char(c);
+ input_stack::get_char();
+ }
+ token_double *= pow(10.0, n);
+ return NUMBER;
+ }
+ case 'n':
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'd') {
+ input_stack::get_char();
+ token_int = n;
+ context_buffer += "nd";
+ return ORDINAL;
+ }
+ input_stack::push_back('n');
+ return NUMBER;
+ case 'r':
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'd') {
+ input_stack::get_char();
+ token_int = n;
+ context_buffer += "rd";
+ return ORDINAL;
+ }
+ input_stack::push_back('r');
+ return NUMBER;
+ case 't':
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'h') {
+ input_stack::get_char();
+ token_int = n;
+ context_buffer += "th";
+ return ORDINAL;
+ }
+ input_stack::push_back('t');
+ return NUMBER;
+ case 's':
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 't') {
+ input_stack::get_char();
+ token_int = n;
+ context_buffer += "st";
+ return ORDINAL;
+ }
+ input_stack::push_back('s');
+ return NUMBER;
+ default:
+ return NUMBER;
+ }
+ break;
+ case '\'':
+ {
+ c = input_stack::peek_char();
+ if (c == 't') {
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == 'h') {
+ input_stack::get_char();
+ context_buffer = "'th";
+ return TH;
+ }
+ else
+ input_stack::push_back('t');
+ }
+ context_buffer = "'";
+ return '\'';
+ }
+ case '.':
+ {
+ c = input_stack::peek_char();
+ if (c != EOF && csdigit(c)) {
+ n = 0;
+ token_double = 0.0;
+ context_buffer = '.';
+ goto got_dot;
+ }
+ return get_token_after_dot(c);
+ }
+ case '<':
+ c = input_stack::peek_char();
+ if (c == '-') {
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ if (c == '>') {
+ input_stack::get_char();
+ context_buffer = "<->";
+ return DOUBLE_ARROW_HEAD;
+ }
+ context_buffer = "<-";
+ return LEFT_ARROW_HEAD;
+ }
+ else if (c == '=') {
+ input_stack::get_char();
+ context_buffer = "<=";
+ return LESSEQUAL;
+ }
+ context_buffer = "<";
+ return '<';
+ case '-':
+ c = input_stack::peek_char();
+ if (c == '>') {
+ input_stack::get_char();
+ context_buffer = "->";
+ return RIGHT_ARROW_HEAD;
+ }
+ context_buffer = "-";
+ return '-';
+ case '!':
+ c = input_stack::peek_char();
+ if (c == '=') {
+ input_stack::get_char();
+ context_buffer = "!=";
+ return NOTEQUAL;
+ }
+ context_buffer = "!";
+ return '!';
+ case '>':
+ c = input_stack::peek_char();
+ if (c == '=') {
+ input_stack::get_char();
+ context_buffer = ">=";
+ return GREATEREQUAL;
+ }
+ context_buffer = ">";
+ return '>';
+ case '=':
+ c = input_stack::peek_char();
+ if (c == '=') {
+ input_stack::get_char();
+ context_buffer = "==";
+ return EQUALEQUAL;
+ }
+ context_buffer = "=";
+ return '=';
+ case '&':
+ c = input_stack::peek_char();
+ if (c == '&') {
+ input_stack::get_char();
+ context_buffer = "&&";
+ return ANDAND;
+ }
+ context_buffer = "&";
+ return '&';
+ case '|':
+ c = input_stack::peek_char();
+ if (c == '|') {
+ input_stack::get_char();
+ context_buffer = "||";
+ return OROR;
+ }
+ context_buffer = "|";
+ return '|';
+ default:
+ if (c != EOF && csalpha(c)) {
+ token_buffer.clear();
+ token_buffer = c;
+ for (;;) {
+ c = input_stack::peek_char();
+ if (c == EOF || (!csalnum(c) && c != '_'))
+ break;
+ input_stack::get_char();
+ token_buffer += char(c);
+ }
+ int tok = lookup_keyword(token_buffer.contents(),
+ token_buffer.length());
+ if (tok != 0) {
+ context_buffer = token_buffer;
+ return tok;
+ }
+ char *def = 0;
+ if (lookup_flag) {
+ token_buffer += '\0';
+ def = macro_table.lookup(token_buffer.contents());
+ token_buffer.set_length(token_buffer.length() - 1);
+ if (def) {
+ if (c == '(') {
+ input_stack::get_char();
+ interpolate_macro_with_args(def);
+ }
+ else
+ input_stack::push(new macro_input(def));
+ }
+ }
+ if (!def) {
+ context_buffer = token_buffer;
+ if (csupper(token_buffer[0]))
+ return LABEL;
+ else
+ return VARIABLE;
+ }
+ }
+ else {
+ context_buffer = char(c);
+ return (unsigned char)c;
+ }
+ break;
+ }
+ }
+}
+
+int get_delimited()
+{
+ token_buffer.clear();
+ int c = input_stack::get_char();
+ while (c == ' ' || c == '\t' || c == '\n')
+ c = input_stack::get_char();
+ if (c == EOF) {
+ lex_error("missing delimiter");
+ return 0;
+ }
+ context_buffer = char(c);
+ int had_newline = 0;
+ int start = c;
+ int level = 0;
+ enum { NORMAL, IN_STRING, IN_STRING_QUOTED, DELIM_END } state = NORMAL;
+ for (;;) {
+ c = input_stack::get_char();
+ if (c == EOF) {
+ lex_error("missing closing delimiter");
+ return 0;
+ }
+ if (c == '\n')
+ had_newline = 1;
+ else if (!had_newline)
+ context_buffer += char(c);
+ switch (state) {
+ case NORMAL:
+ if (start == '{') {
+ if (c == '{') {
+ level++;
+ break;
+ }
+ if (c == '}') {
+ if (--level < 0)
+ state = DELIM_END;
+ break;
+ }
+ }
+ else {
+ if (c == start) {
+ state = DELIM_END;
+ break;
+ }
+ }
+ if (c == '"')
+ state = IN_STRING;
+ break;
+ case IN_STRING_QUOTED:
+ if (c == '\n')
+ state = NORMAL;
+ else
+ state = IN_STRING;
+ break;
+ case IN_STRING:
+ if (c == '"' || c == '\n')
+ state = NORMAL;
+ else if (c == '\\')
+ state = IN_STRING_QUOTED;
+ break;
+ case DELIM_END:
+ // This case it just to shut cfront 2.0 up.
+ default:
+ assert(0);
+ }
+ if (state == DELIM_END)
+ break;
+ token_buffer += c;
+ }
+ return 1;
+}
+
+void do_define()
+{
+ int t = get_token(0); // do not expand what we are defining
+ if (t != VARIABLE && t != LABEL) {
+ lex_error("can only define variable or placename");
+ return;
+ }
+ token_buffer += '\0';
+ string nm = token_buffer;
+ const char *name = nm.contents();
+ if (!get_delimited())
+ return;
+ token_buffer += '\0';
+ macro_table.define(name, strsave(token_buffer.contents()));
+}
+
+void do_undef()
+{
+ int t = get_token(0); // do not expand what we are undefining
+ if (t != VARIABLE && t != LABEL) {
+ lex_error("can only define variable or placename");
+ return;
+ }
+ token_buffer += '\0';
+ macro_table.define(token_buffer.contents(), 0);
+}
+
+
+class for_input : public input {
+ char *var;
+ char *body;
+ double from;
+ double to;
+ int by_is_multiplicative;
+ double by;
+ const char *p;
+ int done_newline;
+public:
+ for_input(char *, double, double, int, double, char *);
+ ~for_input();
+ int get();
+ int peek();
+};
+
+for_input::for_input(char *vr, double f, double t,
+ int bim, double b, char *bd)
+: var(vr), body(bd), from(f), to(t), by_is_multiplicative(bim), by(b),
+ p(body), done_newline(0)
+{
+}
+
+for_input::~for_input()
+{
+ free(var);
+ free(body);
+}
+
+int for_input::get()
+{
+ if (p == 0)
+ return EOF;
+ for (;;) {
+ if (*p != '\0')
+ return (unsigned char)*p++;
+ if (!done_newline) {
+ done_newline = 1;
+ return '\n';
+ }
+ double val;
+ if (!lookup_variable(var, &val)) {
+ lex_error("body of 'for' terminated enclosing block");
+ return EOF;
+ }
+ if (by_is_multiplicative)
+ val *= by;
+ else
+ val += by;
+ define_variable(var, val);
+ if ((from <= to && val > to)
+ || (from >= to && val < to)) {
+ p = 0;
+ return EOF;
+ }
+ p = body;
+ done_newline = 0;
+ }
+}
+
+int for_input::peek()
+{
+ if (p == 0)
+ return EOF;
+ if (*p != '\0')
+ return (unsigned char)*p;
+ if (!done_newline)
+ return '\n';
+ double val;
+ if (!lookup_variable(var, &val))
+ return EOF;
+ if (by_is_multiplicative) {
+ if (val * by > to)
+ return EOF;
+ }
+ else {
+ if ((from <= to && val + by > to)
+ || (from >= to && val + by < to))
+ return EOF;
+ }
+ if (*body == '\0')
+ return EOF;
+ return (unsigned char)*body;
+}
+
+void do_for(char *var, double from, double to, int by_is_multiplicative,
+ double by, char *body)
+{
+ define_variable(var, from);
+ if ((by_is_multiplicative && by <= 0)
+ || (by > 0 && from > to)
+ || (by < 0 && from < to))
+ return;
+ input_stack::push(new for_input(var, from, to,
+ by_is_multiplicative, by, body));
+}
+
+
+void do_copy(const char *filename)
+{
+ errno = 0;
+ FILE *fp = fopen(filename, "r");
+ if (fp == 0) {
+ lex_error("can't open '%1': %2", filename, strerror(errno));
+ return;
+ }
+ input_stack::push(new file_input(fp, filename));
+}
+
+class copy_thru_input : public input {
+ int done;
+ char *body;
+ char *until;
+ const char *p;
+ const char *ap;
+ int argv[MAX_ARG];
+ int argc;
+ string line;
+ int get_line();
+ virtual int inget() = 0;
+public:
+ copy_thru_input(const char *b, const char *u);
+ ~copy_thru_input();
+ int get();
+ int peek();
+};
+
+class copy_file_thru_input : public copy_thru_input {
+ input *in;
+public:
+ copy_file_thru_input(input *, const char *b, const char *u);
+ ~copy_file_thru_input();
+ int inget();
+};
+
+copy_file_thru_input::copy_file_thru_input(input *i, const char *b,
+ const char *u)
+: copy_thru_input(b, u), in(i)
+{
+}
+
+copy_file_thru_input::~copy_file_thru_input()
+{
+ delete in;
+}
+
+int copy_file_thru_input::inget()
+{
+ if (!in)
+ return EOF;
+ else
+ return in->get();
+}
+
+class copy_rest_thru_input : public copy_thru_input {
+public:
+ copy_rest_thru_input(const char *, const char *u);
+ int inget();
+};
+
+copy_rest_thru_input::copy_rest_thru_input(const char *b, const char *u)
+: copy_thru_input(b, u)
+{
+}
+
+int copy_rest_thru_input::inget()
+{
+ while (next != 0) {
+ int c = next->get();
+ if (c != EOF)
+ return c;
+ if (next->next == 0)
+ return EOF;
+ input *tem = next;
+ next = next->next;
+ delete tem;
+ }
+ return EOF;
+
+}
+
+copy_thru_input::copy_thru_input(const char *b, const char *u)
+: done(0)
+{
+ ap = 0;
+ body = process_body(b);
+ p = 0;
+ until = strsave(u);
+}
+
+
+copy_thru_input::~copy_thru_input()
+{
+ delete[] body;
+ delete[] until;
+}
+
+int copy_thru_input::get()
+{
+ if (ap) {
+ if (*ap != '\0')
+ return (unsigned char)*ap++;
+ ap = 0;
+ }
+ for (;;) {
+ if (p == 0) {
+ if (!get_line())
+ break;
+ p = body;
+ }
+ if (*p == '\0') {
+ p = 0;
+ return '\n';
+ }
+ while ((unsigned char)*p >= ARG1
+ && (unsigned char)*p <= ARG1 + MAX_ARG - 1) {
+ int i = (unsigned char)*p++ - ARG1;
+ if (i < argc && line[argv[i]] != '\0') {
+ ap = line.contents() + argv[i];
+ return (unsigned char)*ap++;
+ }
+ }
+ if (*p != '\0')
+ return (unsigned char)*p++;
+ }
+ return EOF;
+}
+
+int copy_thru_input::peek()
+{
+ if (ap) {
+ if (*ap != '\0')
+ return (unsigned char)*ap;
+ ap = 0;
+ }
+ for (;;) {
+ if (p == 0) {
+ if (!get_line())
+ break;
+ p = body;
+ }
+ if (*p == '\0')
+ return '\n';
+ while ((unsigned char)*p >= ARG1
+ && (unsigned char)*p <= ARG1 + MAX_ARG - 1) {
+ int i = (unsigned char)*p++ - ARG1;
+ if (i < argc && line[argv[i]] != '\0') {
+ ap = line.contents() + argv[i];
+ return (unsigned char)*ap;
+ }
+ }
+ if (*p != '\0')
+ return (unsigned char)*p;
+ }
+ return EOF;
+}
+
+int copy_thru_input::get_line()
+{
+ if (done)
+ return 0;
+ line.clear();
+ argc = 0;
+ int c = inget();
+ for (;;) {
+ while (c == ' ')
+ c = inget();
+ if (c == EOF || c == '\n')
+ break;
+ if (argc == MAX_ARG) {
+ do {
+ c = inget();
+ } while (c != '\n' && c != EOF);
+ break;
+ }
+ argv[argc++] = line.length();
+ do {
+ line += char(c);
+ c = inget();
+ } while (c != ' ' && c != '\n');
+ line += '\0';
+ }
+ if (until != 0 && argc > 0 && strcmp(&line[argv[0]], until) == 0) {
+ done = 1;
+ return 0;
+ }
+ return argc > 0 || c == '\n';
+}
+
+class simple_file_input : public input {
+ const char *filename;
+ int lineno;
+ FILE *fp;
+public:
+ simple_file_input(FILE *, const char *);
+ ~simple_file_input();
+ int get();
+ int peek();
+ int get_location(const char **, int *);
+};
+
+simple_file_input::simple_file_input(FILE *p, const char *s)
+: filename(s), lineno(1), fp(p)
+{
+}
+
+simple_file_input::~simple_file_input()
+{
+ // don't delete the filename
+ fclose(fp);
+}
+
+int simple_file_input::get()
+{
+ int c = getc(fp);
+ while (is_invalid_input_char(c)) {
+ error("invalid input character code %1", c);
+ c = getc(fp);
+ }
+ if (c == '\n')
+ lineno++;
+ return c;
+}
+
+int simple_file_input::peek()
+{
+ int c = getc(fp);
+ while (is_invalid_input_char(c)) {
+ error("invalid input character code %1", c);
+ c = getc(fp);
+ }
+ if (c != EOF)
+ ungetc(c, fp);
+ return c;
+}
+
+int simple_file_input::get_location(const char **fnp, int *lnp)
+{
+ *fnp = filename;
+ *lnp = lineno;
+ return 1;
+}
+
+
+void copy_file_thru(const char *filename, const char *body, const char *until)
+{
+ errno = 0;
+ FILE *fp = fopen(filename, "r");
+ if (fp == 0) {
+ lex_error("can't open '%1': %2", filename, strerror(errno));
+ return;
+ }
+ input *in = new copy_file_thru_input(new simple_file_input(fp, filename),
+ body, until);
+ input_stack::push(in);
+}
+
+void copy_rest_thru(const char *body, const char *until)
+{
+ input_stack::push(new copy_rest_thru_input(body, until));
+}
+
+void push_body(const char *s)
+{
+ input_stack::push(new char_input('\n'));
+ input_stack::push(new macro_input(s));
+}
+
+int delim_flag = 0;
+
+char *get_thru_arg()
+{
+ int c = input_stack::peek_char();
+ while (c == ' ') {
+ input_stack::get_char();
+ c = input_stack::peek_char();
+ }
+ if (c != EOF && csalpha(c)) {
+ // looks like a macro
+ input_stack::get_char();
+ token_buffer = c;
+ for (;;) {
+ c = input_stack::peek_char();
+ if (c == EOF || (!csalnum(c) && c != '_'))
+ break;
+ input_stack::get_char();
+ token_buffer += char(c);
+ }
+ context_buffer = token_buffer;
+ token_buffer += '\0';
+ char *def = macro_table.lookup(token_buffer.contents());
+ if (def)
+ return strsave(def);
+ // I guess it wasn't a macro after all; so push the macro name back.
+ // -2 because we added a '\0'
+ for (int i = token_buffer.length() - 2; i >= 0; i--)
+ input_stack::push_back(token_buffer[i]);
+ }
+ if (get_delimited()) {
+ token_buffer += '\0';
+ return strsave(token_buffer.contents());
+ }
+ else
+ return 0;
+}
+
+int lookahead_token = -1;
+string old_context_buffer;
+
+void do_lookahead()
+{
+ if (lookahead_token == -1) {
+ old_context_buffer = context_buffer;
+ lookahead_token = get_token(1);
+ }
+}
+
+int yylex()
+{
+ if (delim_flag) {
+ assert(lookahead_token == -1);
+ if (delim_flag == 2) {
+ if ((yylval.str = get_thru_arg()) != 0)
+ return DELIMITED;
+ else
+ return 0;
+ }
+ else {
+ if (get_delimited()) {
+ token_buffer += '\0';
+ yylval.str = strsave(token_buffer.contents());
+ return DELIMITED;
+ }
+ else
+ return 0;
+ }
+ }
+ for (;;) {
+ int t;
+ if (lookahead_token >= 0) {
+ t = lookahead_token;
+ lookahead_token = -1;
+ }
+ else
+ t = get_token(1);
+ switch (t) {
+ case '\n':
+ return ';';
+ case EOF:
+ return 0;
+ case DEFINE:
+ do_define();
+ break;
+ case UNDEF:
+ do_undef();
+ break;
+ case ORDINAL:
+ yylval.n = token_int;
+ return t;
+ case NUMBER:
+ yylval.x = token_double;
+ return t;
+ case COMMAND_LINE:
+ case TEXT:
+ token_buffer += '\0';
+ if (!input_stack::get_location(&yylval.lstr.filename,
+ &yylval.lstr.lineno)) {
+ yylval.lstr.filename = 0;
+ yylval.lstr.lineno = -1;
+ }
+ yylval.lstr.str = strsave(token_buffer.contents());
+ return t;
+ case LABEL:
+ case VARIABLE:
+ token_buffer += '\0';
+ yylval.str = strsave(token_buffer.contents());
+ return t;
+ case LEFT:
+ // change LEFT to LEFT_CORNER when followed by OF
+ old_context_buffer = context_buffer;
+ lookahead_token = get_token(1);
+ if (lookahead_token == OF)
+ return LEFT_CORNER;
+ else
+ return t;
+ case RIGHT:
+ // change RIGHT to RIGHT_CORNER when followed by OF
+ old_context_buffer = context_buffer;
+ lookahead_token = get_token(1);
+ if (lookahead_token == OF)
+ return RIGHT_CORNER;
+ else
+ return t;
+ case UPPER:
+ // recognise UPPER only before LEFT or RIGHT
+ old_context_buffer = context_buffer;
+ lookahead_token = get_token(1);
+ if (lookahead_token != LEFT && lookahead_token != RIGHT) {
+ yylval.str = strsave("upper");
+ return VARIABLE;
+ }
+ else
+ return t;
+ case LOWER:
+ // recognise LOWER only before LEFT or RIGHT
+ old_context_buffer = context_buffer;
+ lookahead_token = get_token(1);
+ if (lookahead_token != LEFT && lookahead_token != RIGHT) {
+ yylval.str = strsave("lower");
+ return VARIABLE;
+ }
+ else
+ return t;
+ case NORTH:
+ // recognise NORTH only before OF
+ old_context_buffer = context_buffer;
+ lookahead_token = get_token(1);
+ if (lookahead_token != OF) {
+ yylval.str = strsave("north");
+ return VARIABLE;
+ }
+ else
+ return t;
+ case SOUTH:
+ // recognise SOUTH only before OF
+ old_context_buffer = context_buffer;
+ lookahead_token = get_token(1);
+ if (lookahead_token != OF) {
+ yylval.str = strsave("south");
+ return VARIABLE;
+ }
+ else
+ return t;
+ case EAST:
+ // recognise EAST only before OF
+ old_context_buffer = context_buffer;
+ lookahead_token = get_token(1);
+ if (lookahead_token != OF) {
+ yylval.str = strsave("east");
+ return VARIABLE;
+ }
+ else
+ return t;
+ case WEST:
+ // recognise WEST only before OF
+ old_context_buffer = context_buffer;
+ lookahead_token = get_token(1);
+ if (lookahead_token != OF) {
+ yylval.str = strsave("west");
+ return VARIABLE;
+ }
+ else
+ return t;
+ case TOP:
+ // recognise TOP only before OF
+ old_context_buffer = context_buffer;
+ lookahead_token = get_token(1);
+ if (lookahead_token != OF) {
+ yylval.str = strsave("top");
+ return VARIABLE;
+ }
+ else
+ return t;
+ case BOTTOM:
+ // recognise BOTTOM only before OF
+ old_context_buffer = context_buffer;
+ lookahead_token = get_token(1);
+ if (lookahead_token != OF) {
+ yylval.str = strsave("bottom");
+ return VARIABLE;
+ }
+ else
+ return t;
+ case CENTER:
+ // recognise CENTER only before OF
+ old_context_buffer = context_buffer;
+ lookahead_token = get_token(1);
+ if (lookahead_token != OF) {
+ yylval.str = strsave("center");
+ return VARIABLE;
+ }
+ else
+ return t;
+ case START:
+ // recognise START only before OF
+ old_context_buffer = context_buffer;
+ lookahead_token = get_token(1);
+ if (lookahead_token != OF) {
+ yylval.str = strsave("start");
+ return VARIABLE;
+ }
+ else
+ return t;
+ case END:
+ // recognise END only before OF
+ old_context_buffer = context_buffer;
+ lookahead_token = get_token(1);
+ if (lookahead_token != OF) {
+ yylval.str = strsave("end");
+ return VARIABLE;
+ }
+ else
+ return t;
+ default:
+ return t;
+ }
+ }
+}
+
+void lex_error(const char *message,
+ const errarg &arg1,
+ const errarg &arg2,
+ const errarg &arg3)
+{
+ const char *filename;
+ int lineno;
+ if (!input_stack::get_location(&filename, &lineno))
+ error(message, arg1, arg2, arg3);
+ else
+ error_with_file_and_line(filename, lineno, message, arg1, arg2, arg3);
+}
+
+void lex_warning(const char *message,
+ const errarg &arg1,
+ const errarg &arg2,
+ const errarg &arg3)
+{
+ const char *filename;
+ int lineno;
+ if (!input_stack::get_location(&filename, &lineno))
+ warning(message, arg1, arg2, arg3);
+ else
+ warning_with_file_and_line(filename, lineno, message, arg1, arg2, arg3);
+}
+
+void yyerror(const char *s)
+{
+ const char *filename;
+ int lineno;
+ const char *context = 0;
+ if (lookahead_token == -1) {
+ if (context_buffer.length() > 0) {
+ context_buffer += '\0';
+ context = context_buffer.contents();
+ }
+ }
+ else {
+ if (old_context_buffer.length() > 0) {
+ old_context_buffer += '\0';
+ context = old_context_buffer.contents();
+ }
+ }
+ if (!input_stack::get_location(&filename, &lineno)) {
+ if (context) {
+ if (context[0] == '\n' && context[1] == '\0')
+ error("%1 before newline", s);
+ else
+ error("%1 before '%2'", s, context);
+ }
+ else
+ error("%1 at end of picture", s);
+ }
+ else {
+ if (context) {
+ if (context[0] == '\n' && context[1] == '\0')
+ error_with_file_and_line(filename, lineno, "%1 before newline", s);
+ else
+ error_with_file_and_line(filename, lineno, "%1 before '%2'",
+ s, context);
+ }
+ else
+ error_with_file_and_line(filename, lineno, "%1 at end of picture", s);
+ }
+}
+