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Diffstat (limited to 'usr/dash/bltin/test.c')
| -rw-r--r-- | usr/dash/bltin/test.c | 543 |
1 files changed, 543 insertions, 0 deletions
diff --git a/usr/dash/bltin/test.c b/usr/dash/bltin/test.c new file mode 100644 index 0000000..90135e1 --- /dev/null +++ b/usr/dash/bltin/test.c @@ -0,0 +1,543 @@ +/* + * test(1); version 7-like -- author Erik Baalbergen + * modified by Eric Gisin to be used as built-in. + * modified by Arnold Robbins to add SVR3 compatibility + * (-x -c -b -p -u -g -k) plus Korn's -L -nt -ot -ef and new -S (socket). + * modified by J.T. Conklin for NetBSD. + * + * This program is in the Public Domain. + */ + +#include <sys/stat.h> +#include <sys/types.h> + +#include <fcntl.h> +#include <inttypes.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <stdarg.h> +#include "bltin.h" + +/* test(1) accepts the following grammar: + oexpr ::= aexpr | aexpr "-o" oexpr ; + aexpr ::= nexpr | nexpr "-a" aexpr ; + nexpr ::= primary | "!" primary + primary ::= unary-operator operand + | operand binary-operator operand + | operand + | "(" oexpr ")" + ; + unary-operator ::= "-r"|"-w"|"-x"|"-f"|"-d"|"-c"|"-b"|"-p"| + "-u"|"-g"|"-k"|"-s"|"-t"|"-z"|"-n"|"-o"|"-O"|"-G"|"-L"|"-S"; + + binary-operator ::= "="|"!="|"-eq"|"-ne"|"-ge"|"-gt"|"-le"|"-lt"| + "-nt"|"-ot"|"-ef"; + operand ::= <any legal UNIX file name> +*/ + +enum token { + EOI, + FILRD, + FILWR, + FILEX, + FILEXIST, + FILREG, + FILDIR, + FILCDEV, + FILBDEV, + FILFIFO, + FILSOCK, + FILSYM, + FILGZ, + FILTT, + FILSUID, + FILSGID, + FILSTCK, + FILNT, + FILOT, + FILEQ, + FILUID, + FILGID, + STREZ, + STRNZ, + STREQ, + STRNE, + STRLT, + STRGT, + INTEQ, + INTNE, + INTGE, + INTGT, + INTLE, + INTLT, + UNOT, + BAND, + BOR, + LPAREN, + RPAREN, + OPERAND +}; + +enum token_types { + UNOP, + BINOP, + BUNOP, + BBINOP, + PAREN +}; + +static struct t_op { + const char *op_text; + short op_num, op_type; +} const ops [] = { + {"-r", FILRD, UNOP}, + {"-w", FILWR, UNOP}, + {"-x", FILEX, UNOP}, + {"-e", FILEXIST,UNOP}, + {"-f", FILREG, UNOP}, + {"-d", FILDIR, UNOP}, + {"-c", FILCDEV,UNOP}, + {"-b", FILBDEV,UNOP}, + {"-p", FILFIFO,UNOP}, + {"-u", FILSUID,UNOP}, + {"-g", FILSGID,UNOP}, + {"-k", FILSTCK,UNOP}, + {"-s", FILGZ, UNOP}, + {"-t", FILTT, UNOP}, + {"-z", STREZ, UNOP}, + {"-n", STRNZ, UNOP}, + {"-h", FILSYM, UNOP}, /* for backwards compat */ + {"-O", FILUID, UNOP}, + {"-G", FILGID, UNOP}, + {"-L", FILSYM, UNOP}, + {"-S", FILSOCK,UNOP}, + {"=", STREQ, BINOP}, + {"!=", STRNE, BINOP}, + {"<", STRLT, BINOP}, + {">", STRGT, BINOP}, + {"-eq", INTEQ, BINOP}, + {"-ne", INTNE, BINOP}, + {"-ge", INTGE, BINOP}, + {"-gt", INTGT, BINOP}, + {"-le", INTLE, BINOP}, + {"-lt", INTLT, BINOP}, + {"-nt", FILNT, BINOP}, + {"-ot", FILOT, BINOP}, + {"-ef", FILEQ, BINOP}, + {"!", UNOT, BUNOP}, + {"-a", BAND, BBINOP}, + {"-o", BOR, BBINOP}, + {"(", LPAREN, PAREN}, + {")", RPAREN, PAREN}, + {0, 0, 0} +}; + +static char **t_wp; +static struct t_op const *t_wp_op; + +static void syntax(const char *, const char *); +static int oexpr(enum token); +static int aexpr(enum token); +static int nexpr(enum token); +static int primary(enum token); +static int binop(void); +static int filstat(char *, enum token); +static enum token t_lex(char **); +static int isoperand(char **); +static int newerf(const char *, const char *); +static int olderf(const char *, const char *); +static int equalf(const char *, const char *); +#ifdef HAVE_FACCESSAT +static int test_file_access(const char *, int); +#else +static int test_st_mode(const struct stat64 *, int); +static int bash_group_member(gid_t); +#endif + +static inline intmax_t getn(const char *s) +{ + return atomax10(s); +} + +static const struct t_op *getop(const char *s) +{ + const struct t_op *op; + + for (op = ops; op->op_text; op++) { + if (strcmp(s, op->op_text) == 0) + return op; + } + + return NULL; +} + +int +testcmd(int argc, char **argv) +{ + const struct t_op *op; + enum token n; + int res; + + if (*argv[0] == '[') { + if (*argv[--argc] != ']') + error("missing ]"); + argv[argc] = NULL; + } + + argv++; + argc--; + + if (argc < 1) + return 1; + + /* + * POSIX prescriptions: he who wrote this deserves the Nobel + * peace prize. + */ + switch (argc) { + case 3: + op = getop(argv[1]); + if (op && op->op_type == BINOP) { + n = OPERAND; + goto eval; + } + /* fall through */ + + case 4: + if (!strcmp(argv[0], "(") && !strcmp(argv[argc - 1], ")")) { + argv[--argc] = NULL; + argv++; + argc--; + } + } + + n = t_lex(argv); + +eval: + t_wp = argv; + res = !oexpr(n); + argv = t_wp; + + if (argv[0] != NULL && argv[1] != NULL) + syntax(argv[0], "unexpected operator"); + + return res; +} + +static void +syntax(const char *op, const char *msg) +{ + if (op && *op) + error("%s: %s", op, msg); + else + error("%s", msg); +} + +static int +oexpr(enum token n) +{ + int res = 0; + + for (;;) { + res |= aexpr(n); + n = t_lex(t_wp + 1); + if (n != BOR) + break; + n = t_lex(t_wp += 2); + } + return res; +} + +static int +aexpr(enum token n) +{ + int res = 1; + + for (;;) { + if (!nexpr(n)) + res = 0; + n = t_lex(t_wp + 1); + if (n != BAND) + break; + n = t_lex(t_wp += 2); + } + return res; +} + +static int +nexpr(enum token n) +{ + if (n == UNOT) + return !nexpr(t_lex(++t_wp)); + return primary(n); +} + +static int +primary(enum token n) +{ + enum token nn; + int res; + + if (n == EOI) + return 0; /* missing expression */ + if (n == LPAREN) { + if ((nn = t_lex(++t_wp)) == RPAREN) + return 0; /* missing expression */ + res = oexpr(nn); + if (t_lex(++t_wp) != RPAREN) + syntax(NULL, "closing paren expected"); + return res; + } + if (t_wp_op && t_wp_op->op_type == UNOP) { + /* unary expression */ + if (*++t_wp == NULL) + syntax(t_wp_op->op_text, "argument expected"); + switch (n) { + case STREZ: + return strlen(*t_wp) == 0; + case STRNZ: + return strlen(*t_wp) != 0; + case FILTT: + return isatty(getn(*t_wp)); +#ifdef HAVE_FACCESSAT + case FILRD: + return test_file_access(*t_wp, R_OK); + case FILWR: + return test_file_access(*t_wp, W_OK); + case FILEX: + return test_file_access(*t_wp, X_OK); +#endif + default: + return filstat(*t_wp, n); + } + } + + if (t_lex(t_wp + 1), t_wp_op && t_wp_op->op_type == BINOP) { + return binop(); + } + + return strlen(*t_wp) > 0; +} + +static int +binop(void) +{ + const char *opnd1, *opnd2; + struct t_op const *op; + + opnd1 = *t_wp; + (void) t_lex(++t_wp); + op = t_wp_op; + + if ((opnd2 = *++t_wp) == (char *)0) + syntax(op->op_text, "argument expected"); + + switch (op->op_num) { + default: +#ifdef DEBUG + abort(); + /* NOTREACHED */ +#endif + case STREQ: + return strcmp(opnd1, opnd2) == 0; + case STRNE: + return strcmp(opnd1, opnd2) != 0; + case STRLT: + return strcmp(opnd1, opnd2) < 0; + case STRGT: + return strcmp(opnd1, opnd2) > 0; + case INTEQ: + return getn(opnd1) == getn(opnd2); + case INTNE: + return getn(opnd1) != getn(opnd2); + case INTGE: + return getn(opnd1) >= getn(opnd2); + case INTGT: + return getn(opnd1) > getn(opnd2); + case INTLE: + return getn(opnd1) <= getn(opnd2); + case INTLT: + return getn(opnd1) < getn(opnd2); + case FILNT: + return newerf (opnd1, opnd2); + case FILOT: + return olderf (opnd1, opnd2); + case FILEQ: + return equalf (opnd1, opnd2); + } +} + +static int +filstat(char *nm, enum token mode) +{ + struct stat64 s; + + if (mode == FILSYM ? lstat64(nm, &s) : stat64(nm, &s)) + return 0; + + switch (mode) { +#ifndef HAVE_FACCESSAT + case FILRD: + return test_st_mode(&s, R_OK); + case FILWR: + return test_st_mode(&s, W_OK); + case FILEX: + return test_st_mode(&s, X_OK); +#endif + case FILEXIST: + return 1; + case FILREG: + return S_ISREG(s.st_mode); + case FILDIR: + return S_ISDIR(s.st_mode); + case FILCDEV: + return S_ISCHR(s.st_mode); + case FILBDEV: + return S_ISBLK(s.st_mode); + case FILFIFO: + return S_ISFIFO(s.st_mode); + case FILSOCK: + return S_ISSOCK(s.st_mode); + case FILSYM: + return S_ISLNK(s.st_mode); + case FILSUID: + return (s.st_mode & S_ISUID) != 0; + case FILSGID: + return (s.st_mode & S_ISGID) != 0; + case FILSTCK: + return (s.st_mode & S_ISVTX) != 0; + case FILGZ: + return !!s.st_size; + case FILUID: + return s.st_uid == geteuid(); + case FILGID: + return s.st_gid == getegid(); + default: + return 1; + } +} + +static enum token t_lex(char **tp) +{ + struct t_op const *op; + char *s = *tp; + + if (s == 0) { + t_wp_op = (struct t_op *)0; + return EOI; + } + + op = getop(s); + if (op && !(op->op_type == UNOP && isoperand(tp)) && + !(op->op_num == LPAREN && !tp[1])) { + t_wp_op = op; + return op->op_num; + } + + t_wp_op = (struct t_op *)0; + return OPERAND; +} + +static int isoperand(char **tp) +{ + struct t_op const *op; + char *s; + + if (!(s = tp[1])) + return 1; + if (!tp[2]) + return 0; + + op = getop(s); + return op && op->op_type == BINOP; +} + +static int +newerf (const char *f1, const char *f2) +{ + struct stat b1, b2; + + return (stat (f1, &b1) == 0 && + stat (f2, &b2) == 0 && + b1.st_mtime > b2.st_mtime); +} + +static int +olderf (const char *f1, const char *f2) +{ + struct stat b1, b2; + + return (stat (f1, &b1) == 0 && + stat (f2, &b2) == 0 && + b1.st_mtime < b2.st_mtime); +} + +static int +equalf (const char *f1, const char *f2) +{ + struct stat b1, b2; + + return (stat (f1, &b1) == 0 && + stat (f2, &b2) == 0 && + b1.st_dev == b2.st_dev && + b1.st_ino == b2.st_ino); +} + +#ifdef HAVE_FACCESSAT +static int test_file_access(const char *path, int mode) +{ + return !faccessat(AT_FDCWD, path, mode, AT_EACCESS); +} +#else /* HAVE_FACCESSAT */ +/* + * Similar to what access(2) does, but uses the effective uid and gid. + * Doesn't make the mistake of telling root that any file is executable. + * Returns non-zero if the file is accessible. + */ +static int +test_st_mode(const struct stat64 *st, int mode) +{ + int euid = geteuid(); + + if (euid == 0) { + /* Root can read or write any file. */ + if (mode != X_OK) + return 1; + + /* Root can execute any file that has any one of the execute + bits set. */ + mode = S_IXUSR | S_IXGRP | S_IXOTH; + } else if (st->st_uid == euid) + mode <<= 6; + else if (bash_group_member(st->st_gid)) + mode <<= 3; + + return st->st_mode & mode; +} + +/* Return non-zero if GID is one that we have in our groups list. */ +static int +bash_group_member(gid_t gid) +{ + register int i; + gid_t *group_array; + int ngroups; + + /* Short-circuit if possible, maybe saving a call to getgroups(). */ + if (gid == getgid() || gid == getegid()) + return (1); + + ngroups = getgroups(0, NULL); + group_array = stalloc(ngroups * sizeof(gid_t)); + if ((getgroups(ngroups, group_array)) != ngroups) + return (0); + + /* Search through the list looking for GID. */ + for (i = 0; i < ngroups; i++) + if (gid == group_array[i]) + return (1); + + return (0); +} +#endif /* HAVE_FACCESSAT */ |