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Diffstat (limited to 'sysdeps/generic/wordexp.c')
| -rw-r--r-- | sysdeps/generic/wordexp.c | 2452 |
1 files changed, 2452 insertions, 0 deletions
diff --git a/sysdeps/generic/wordexp.c b/sysdeps/generic/wordexp.c new file mode 100644 index 0000000000..82765e1820 --- /dev/null +++ b/sysdeps/generic/wordexp.c @@ -0,0 +1,2452 @@ +/* POSIX.2 wordexp implementation. + Copyright (C) 1997, 1998, 1999, 2000, 2001 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Tim Waugh <tim@cyberelk.demon.co.uk>. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public License as + published by the Free Software Foundation; either version 2 of the + License, or (at your option) any later version. + + The GNU C Library 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with the GNU C Library; see the file COPYING.LIB. If not, + write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. */ + +#include <wordexp.h> +#include <signal.h> +#include <stdlib.h> +#include <pwd.h> +#include <sys/types.h> +#include <string.h> +#include <glob.h> +#include <ctype.h> +#include <sys/time.h> +#include <sys/types.h> +#include <sys/wait.h> +#include <unistd.h> +#include <fcntl.h> +#include <sys/stat.h> +#include <paths.h> +#include <errno.h> +#include <sys/param.h> +#include <stdio.h> +#include <fnmatch.h> + +#include <stdio-common/_itoa.h> + +/* Undefine the following line for the production version. */ +/* #define NDEBUG 1 */ +#include <assert.h> + +/* Get some device information. */ +#include <device-nrs.h> + +/* + * This is a recursive-descent-style word expansion routine. + */ + +/* These variables are defined and initialized in the startup code. */ +extern int __libc_argc; +extern char **__libc_argv; + +/* Some forward declarations */ +static int parse_dollars (char **word, size_t *word_length, size_t *max_length, + const char *words, size_t *offset, int flags, + wordexp_t *pwordexp, const char *ifs, + const char *ifs_white, int quoted) + internal_function; +static int parse_backtick (char **word, size_t *word_length, + size_t *max_length, const char *words, + size_t *offset, int flags, wordexp_t *pwordexp, + const char *ifs, const char *ifs_white) + internal_function; +static int parse_dquote (char **word, size_t *word_length, size_t *max_length, + const char *words, size_t *offset, int flags, + wordexp_t *pwordexp, const char *ifs, + const char *ifs_white) + internal_function; +static int eval_expr (char *expr, long int *result) internal_function; + +/* The w_*() functions manipulate word lists. */ + +#define W_CHUNK (100) + +/* Result of w_newword will be ignored if it's the last word. */ +static inline char * +w_newword (size_t *actlen, size_t *maxlen) +{ + *actlen = *maxlen = 0; + return NULL; +} + +static inline char * +w_addchar (char *buffer, size_t *actlen, size_t *maxlen, char ch) + /* (lengths exclude trailing zero) */ +{ + /* Add a character to the buffer, allocating room for it if needed. + */ + + if (*actlen == *maxlen) + { + char *old_buffer = buffer; + assert (buffer == NULL || *maxlen != 0); + *maxlen += W_CHUNK; + buffer = realloc (buffer, 1 + *maxlen); + + if (buffer == NULL) + free (old_buffer); + } + + if (buffer != NULL) + { + buffer[*actlen] = ch; + buffer[++(*actlen)] = '\0'; + } + + return buffer; +} + +static char * +internal_function +w_addmem (char *buffer, size_t *actlen, size_t *maxlen, const char *str, + size_t len) +{ + /* Add a string to the buffer, allocating room for it if needed. + */ + if (*actlen + len > *maxlen) + { + char *old_buffer = buffer; + assert (buffer == NULL || *maxlen != 0); + *maxlen += MAX (2 * len, W_CHUNK); + buffer = realloc (old_buffer, 1 + *maxlen); + + if (buffer == NULL) + free (old_buffer); + } + + if (buffer != NULL) + { + *((char *) __mempcpy (&buffer[*actlen], str, len)) = '\0'; + *actlen += len; + } + + return buffer; +} + +static char * +internal_function +w_addstr (char *buffer, size_t *actlen, size_t *maxlen, const char *str) + /* (lengths exclude trailing zero) */ +{ + /* Add a string to the buffer, allocating room for it if needed. + */ + size_t len; + + assert (str != NULL); /* w_addstr only called from this file */ + len = strlen (str); + + return w_addmem (buffer, actlen, maxlen, str, len); +} + +static int +internal_function +w_addword (wordexp_t *pwordexp, char *word) +{ + /* Add a word to the wordlist */ + size_t num_p; + char **new_wordv; + + /* Internally, NULL acts like "". Convert NULLs to "" before + * the caller sees them. + */ + if (word == NULL) + { + word = __strdup (""); + if (word == NULL) + goto no_space; + } + + num_p = 2 + pwordexp->we_wordc + pwordexp->we_offs; + new_wordv = realloc (pwordexp->we_wordv, sizeof (char *) * num_p); + if (new_wordv != NULL) + { + pwordexp->we_wordv = new_wordv; + pwordexp->we_wordv[pwordexp->we_offs + pwordexp->we_wordc++] = word; + pwordexp->we_wordv[pwordexp->we_offs + pwordexp->we_wordc] = NULL; + return 0; + } + +no_space: + return WRDE_NOSPACE; +} + +/* The parse_*() functions should leave *offset being the offset in 'words' + * to the last character processed. + */ + +static int +internal_function +parse_backslash (char **word, size_t *word_length, size_t *max_length, + const char *words, size_t *offset) +{ + /* We are poised _at_ a backslash, not in quotes */ + + switch (words[1 + *offset]) + { + case 0: + /* Backslash is last character of input words */ + return WRDE_SYNTAX; + + case '\n': + ++(*offset); + break; + + default: + *word = w_addchar (*word, word_length, max_length, words[1 + *offset]); + if (*word == NULL) + return WRDE_NOSPACE; + + ++(*offset); + break; + } + + return 0; +} + +static int +internal_function +parse_qtd_backslash (char **word, size_t *word_length, size_t *max_length, + const char *words, size_t *offset) +{ + /* We are poised _at_ a backslash, inside quotes */ + + switch (words[1 + *offset]) + { + case 0: + /* Backslash is last character of input words */ + return WRDE_SYNTAX; + + case '\n': + ++(*offset); + break; + + case '$': + case '`': + case '"': + case '\\': + *word = w_addchar (*word, word_length, max_length, words[1 + *offset]); + if (*word == NULL) + return WRDE_NOSPACE; + + ++(*offset); + break; + + default: + *word = w_addchar (*word, word_length, max_length, words[*offset]); + if (*word != NULL) + *word = w_addchar (*word, word_length, max_length, words[1 + *offset]); + + if (*word == NULL) + return WRDE_NOSPACE; + + ++(*offset); + break; + } + + return 0; +} + +static int +internal_function +parse_tilde (char **word, size_t *word_length, size_t *max_length, + const char *words, size_t *offset, size_t wordc) +{ + /* We are poised _at_ a tilde */ + size_t i; + + if (*word_length != 0) + { + if (!((*word)[*word_length - 1] == '=' && wordc == 0)) + { + if (!((*word)[*word_length - 1] == ':' + && strchr (*word, '=') && wordc == 0)) + { + *word = w_addchar (*word, word_length, max_length, '~'); + return *word ? 0 : WRDE_NOSPACE; + } + } + } + + for (i = 1 + *offset; words[i]; i++) + { + if (words[i] == ':' || words[i] == '/' || words[i] == ' ' || + words[i] == '\t' || words[i] == 0 ) + break; + + if (words[i] == '\\') + { + *word = w_addchar (*word, word_length, max_length, '~'); + return *word ? 0 : WRDE_NOSPACE; + } + } + + if (i == 1 + *offset) + { + /* Tilde appears on its own */ + uid_t uid; + struct passwd pwd, *tpwd; + int buflen = 1000; + char* home; + char* buffer; + int result; + + /* POSIX.2 says ~ expands to $HOME and if HOME is unset the + results are unspecified. We do a lookup on the uid if + HOME is unset. */ + + home = getenv ("HOME"); + if (home != NULL) + { + *word = w_addstr (*word, word_length, max_length, home); + if (*word == NULL) + return WRDE_NOSPACE; + } + else + { + uid = __getuid (); + buffer = __alloca (buflen); + + while ((result = __getpwuid_r (uid, &pwd, buffer, buflen, &tpwd)) != 0 + && errno == ERANGE) + { + buflen += 1000; + buffer = __alloca (buflen); + } + + if (result == 0 && tpwd != NULL && pwd.pw_dir != NULL) + { + *word = w_addstr (*word, word_length, max_length, pwd.pw_dir); + if (*word == NULL) + return WRDE_NOSPACE; + } + else + { + *word = w_addchar (*word, word_length, max_length, '~'); + if (*word == NULL) + return WRDE_NOSPACE; + } + } + } + else + { + /* Look up user name in database to get home directory */ + char *user = __strndup (&words[1 + *offset], i - (1 + *offset)); + struct passwd pwd, *tpwd; + int buflen = 1000; + char* buffer = __alloca (buflen); + int result; + + while ((result = __getpwnam_r (user, &pwd, buffer, buflen, &tpwd)) != 0 + && errno == ERANGE) + { + buflen += 1000; + buffer = __alloca (buflen); + } + + if (result == 0 && tpwd != NULL && pwd.pw_dir) + *word = w_addstr (*word, word_length, max_length, pwd.pw_dir); + else + { + /* (invalid login name) */ + *word = w_addchar (*word, word_length, max_length, '~'); + if (*word != NULL) + *word = w_addstr (*word, word_length, max_length, user); + } + + *offset = i - 1; + } + return *word ? 0 : WRDE_NOSPACE; +} + + +static int +internal_function +do_parse_glob (const char *glob_word, char **word, size_t *word_length, + size_t *max_length, wordexp_t *pwordexp, const char *ifs, + const char *ifs_white) +{ + int error; + unsigned int match; + glob_t globbuf; + + error = glob (glob_word, GLOB_NOCHECK, NULL, &globbuf); + + if (error != 0) + { + /* We can only run into memory problems. */ + assert (error == GLOB_NOSPACE); + return WRDE_NOSPACE; + } + + if (ifs && !*ifs) + { + /* No field splitting allowed. */ + assert (globbuf.gl_pathv[0] != NULL); + *word = w_addstr (*word, word_length, max_length, globbuf.gl_pathv[0]); + for (match = 1; match < globbuf.gl_pathc && *word != NULL; ++match) + { + *word = w_addchar (*word, word_length, max_length, ' '); + if (*word != NULL) + *word = w_addstr (*word, word_length, max_length, + globbuf.gl_pathv[match]); + } + + globfree (&globbuf); + return *word ? 0 : WRDE_NOSPACE; + } + + assert (ifs == NULL || *ifs != '\0'); + if (*word != NULL) + { + free (*word); + *word = w_newword (word_length, max_length); + } + + for (match = 0; match < globbuf.gl_pathc; ++match) + { + char *matching_word = __strdup (globbuf.gl_pathv[match]); + if (matching_word == NULL || w_addword (pwordexp, matching_word)) + { + globfree (&globbuf); + return WRDE_NOSPACE; + } + } + + globfree (&globbuf); + return 0; +} + +static int +internal_function +parse_glob (char **word, size_t *word_length, size_t *max_length, + const char *words, size_t *offset, int flags, + wordexp_t *pwordexp, const char *ifs, const char *ifs_white) +{ + /* We are poised just after a '*', a '[' or a '?'. */ + int error = WRDE_NOSPACE; + int quoted = 0; /* 1 if singly-quoted, 2 if doubly */ + int i; + wordexp_t glob_list; /* List of words to glob */ + + glob_list.we_wordc = 0; + glob_list.we_wordv = NULL; + glob_list.we_offs = 0; + for (; words[*offset] != '\0'; ++*offset) + { + if ((ifs && strchr (ifs, words[*offset])) || + (!ifs && strchr (" \t\n", words[*offset]))) + /* Reached IFS */ + break; + + /* Sort out quoting */ + if (words[*offset] == '\'') + { + if (quoted == 0) + { + quoted = 1; + continue; + } + else if (quoted == 1) + { + quoted = 0; + continue; + } + } + else if (words[*offset] == '"') + { + if (quoted == 0) + { + quoted = 2; + continue; + } + else if (quoted == 2) + { + quoted = 0; + continue; + } + } + + /* Sort out other special characters */ + if (quoted != 1 && words[*offset] == '$') + { + error = parse_dollars (word, word_length, max_length, words, + offset, flags, &glob_list, ifs, ifs_white, + quoted == 2); + if (error) + goto tidy_up; + + continue; + } + else if (words[*offset] == '\\') + { + if (quoted) + error = parse_qtd_backslash (word, word_length, max_length, + words, offset); + else + error = parse_backslash (word, word_length, max_length, + words, offset); + + if (error) + goto tidy_up; + + continue; + } + + *word = w_addchar (*word, word_length, max_length, words[*offset]); + if (*word == NULL) + goto tidy_up; + } + + /* Don't forget to re-parse the character we stopped at. */ + --*offset; + + /* Glob the words */ + error = w_addword (&glob_list, *word); + *word = w_newword (word_length, max_length); + for (i = 0; error == 0 && i < glob_list.we_wordc; i++) + error = do_parse_glob (glob_list.we_wordv[i], word, word_length, + max_length, pwordexp, ifs, ifs_white); + + /* Now tidy up */ +tidy_up: + wordfree (&glob_list); + return error; +} + +static int +internal_function +parse_squote (char **word, size_t *word_length, size_t *max_length, + const char *words, size_t *offset) +{ + /* We are poised just after a single quote */ + for (; words[*offset]; ++(*offset)) + { + if (words[*offset] != '\'') + { + *word = w_addchar (*word, word_length, max_length, words[*offset]); + if (*word == NULL) + return WRDE_NOSPACE; + } + else return 0; + } + + /* Unterminated string */ + return WRDE_SYNTAX; +} + +/* Functions to evaluate an arithmetic expression */ +static int +internal_function +eval_expr_val (char **expr, long int *result) +{ + int sgn = +1; + char *digit; + + /* Skip white space */ + for (digit = *expr; digit && *digit && isspace (*digit); ++digit); + + switch (*digit) + { + case '(': + + /* Scan for closing paren */ + for (++digit; **expr && **expr != ')'; ++(*expr)); + + /* Is there one? */ + if (!**expr) + return WRDE_SYNTAX; + + *(*expr)++ = 0; + + if (eval_expr (digit, result)) + return WRDE_SYNTAX; + + return 0; + + case '+': /* Positive value */ + ++digit; + break; + + case '-': /* Negative value */ + ++digit; + sgn = -1; + break; + + default: + if (!isdigit (*digit)) + return WRDE_SYNTAX; + } + + *result = 0; + for (; *digit && isdigit (*digit); ++digit) + *result = (*result * 10) + (*digit - '0'); + + *expr = digit; + *result *= sgn; + return 0; +} + +static int +internal_function +eval_expr_multdiv (char **expr, long int *result) +{ + long int arg; + + /* Read a Value */ + if (eval_expr_val (expr, result) != 0) + return WRDE_SYNTAX; + + while (**expr) + { + /* Skip white space */ + for (; *expr && **expr && isspace (**expr); ++(*expr)); + + if (**expr == '*') + { + ++(*expr); + if (eval_expr_val (expr, &arg) != 0) + return WRDE_SYNTAX; + + *result *= arg; + } + else if (**expr == '/') + { + ++(*expr); + if (eval_expr_val (expr, &arg) != 0) + return WRDE_SYNTAX; + + *result /= arg; + } + else break; + } + + return 0; +} + +static int +internal_function +eval_expr (char *expr, long int *result) +{ + long int arg; + + /* Read a Multdiv */ + if (eval_expr_multdiv (&expr, result) != 0) + return WRDE_SYNTAX; + + while (*expr) + { + /* Skip white space */ + for (; expr && *expr && isspace (*expr); ++expr); + + if (*expr == '+') + { + ++expr; + if (eval_expr_multdiv (&expr, &arg) != 0) + return WRDE_SYNTAX; + + *result += arg; + } + else if (*expr == '-') + { + ++expr; + if (eval_expr_multdiv (&expr, &arg) != 0) + return WRDE_SYNTAX; + + *result -= arg; + } + else break; + } + + return 0; +} + +static int +internal_function +parse_arith (char **word, size_t *word_length, size_t *max_length, + const char *words, size_t *offset, int flags, int bracket) +{ + /* We are poised just after "$((" or "$[" */ + int error; + int paren_depth = 1; + size_t expr_length; + size_t expr_maxlen; + char *expr; + + expr = w_newword (&expr_length, &expr_maxlen); + for (; words[*offset]; ++(*offset)) + { + switch (words[*offset]) + { + case '$': + error = parse_dollars (&expr, &expr_length, &expr_maxlen, + words, offset, flags, NULL, NULL, NULL, 1); + /* The ``1'' here is to tell parse_dollars not to + * split the fields. + */ + if (error) + { + free (expr); + return error; + } + break; + + case '`': + (*offset)++; + error = parse_backtick (&expr, &expr_length, &expr_maxlen, + words, offset, flags, NULL, NULL, NULL); + /* The first NULL here is to tell parse_backtick not to + * split the fields. + */ + if (error) + { + free (expr); + return error; + } + break; + + case '\\': + error = parse_qtd_backslash (&expr, &expr_length, &expr_maxlen, + words, offset); + if (error) + { + free (expr); + return error; + } + /* I think that a backslash within an + * arithmetic expansion is bound to + * cause an error sooner or later anyway though. + */ + break; + + case ')': + if (--paren_depth == 0) + { + char result[21]; /* 21 = ceil(log10(2^64)) + 1 */ + long int numresult = 0; + long long int convertme; + + if (bracket || words[1 + *offset] != ')') + { + free (expr); + return WRDE_SYNTAX; + } + + ++(*offset); + + /* Go - evaluate. */ + if (*expr && eval_expr (expr, &numresult) != 0) + { + free (expr); + return WRDE_SYNTAX; + } + + if (numresult < 0) + { + convertme = -numresult; + *word = w_addchar (*word, word_length, max_length, '-'); + if (!*word) + { + free (expr); + return WRDE_NOSPACE; + } + } + else + convertme = numresult; + + result[20] = '\0'; + *word = w_addstr (*word, word_length, max_length, + _itoa (convertme, &result[20], 10, 0)); + free (expr); + return *word ? 0 : WRDE_NOSPACE; + } + expr = w_addchar (expr, &expr_length, &expr_maxlen, words[*offset]); + if (expr == NULL) + return WRDE_NOSPACE; + + break; + + case ']': + if (bracket && paren_depth == 1) + { + char result[21]; /* 21 = ceil(log10(2^64)) + 1 */ + long int numresult = 0; + + /* Go - evaluate. */ + if (*expr && eval_expr (expr, &numresult) != 0) + { + free (expr); + return WRDE_SYNTAX; + } + + result[20] = '\0'; + *word = w_addstr (*word, word_length, max_length, + _itoa_word (numresult, &result[20], 10, 0)); + free (expr); + return *word ? 0 : WRDE_NOSPACE; + } + + free (expr); + return WRDE_SYNTAX; + + case '\n': + case ';': + case '{': + case '}': + free (expr); + return WRDE_BADCHAR; + + case '(': + ++paren_depth; + default: + expr = w_addchar (expr, &expr_length, &expr_maxlen, words[*offset]); + if (expr == NULL) + return WRDE_NOSPACE; + } + } + + /* Premature end */ + free (expr); + return WRDE_SYNTAX; +} + +/* Function called by child process in exec_comm() */ +static void +internal_function +exec_comm_child (char *comm, int *fildes, int showerr, int noexec) +{ + const char *args[4] = { _PATH_BSHELL, "-c", comm, NULL }; + + /* Execute the command, or just check syntax? */ + if (noexec) + args[1] = "-nc"; + + /* Redirect output. */ + __dup2 (fildes[1], 1); + __close (fildes[1]); + + /* Redirect stderr to /dev/null if we have to. */ + if (showerr == 0) + { + struct stat64 st; + int fd; + __close (2); + fd = __open (_PATH_DEVNULL, O_WRONLY); + if (fd >= 0 && fd != 2) + { + __dup2 (fd, 2); + __close (fd); + } + /* Be paranoid. Check that we actually opened the /dev/null + device. */ + if (__builtin_expect (__fxstat64 (_STAT_VER, 2, &st), 0) != 0 + || __builtin_expect (S_ISCHR (st.st_mode), 1) == 0 +#if defined DEV_NULL_MAJOR && defined DEV_NULL_MINOR + || st.st_rdev != makedev (DEV_NULL_MAJOR, DEV_NULL_MINOR) +#endif + ) + /* It's not the /dev/null device. Stop right here. The + problem is: how do we stop? We use _exit() with an + hopefully unusual exit code. */ + _exit (90); + } + + /* Make sure the subshell doesn't field-split on our behalf. */ + __unsetenv ("IFS"); + + __close (fildes[0]); + __execve (_PATH_BSHELL, (char *const *) args, __environ); + + /* Bad. What now? */ + abort (); +} + +/* Function to execute a command and retrieve the results */ +/* pwordexp contains NULL if field-splitting is forbidden */ +static int +internal_function +exec_comm (char *comm, char **word, size_t *word_length, size_t *max_length, + int flags, wordexp_t *pwordexp, const char *ifs, + const char *ifs_white) +{ + int fildes[2]; + int bufsize = 128; + int buflen; + int i; + int status = 0; + size_t maxnewlines = 0; + char *buffer; + pid_t pid; + + /* Don't fork() unless necessary */ + if (!comm || !*comm) + return 0; + + if (__pipe (fildes)) + /* Bad */ + return WRDE_NOSPACE; + + if ((pid = __fork ()) < 0) + { + /* Bad */ + __close (fildes[0]); + __close (fildes[1]); + return WRDE_NOSPACE; + } + + if (pid == 0) + exec_comm_child(comm, fildes, (flags & WRDE_SHOWERR), 0); + + /* Parent */ + + __close (fildes[1]); + buffer = __alloca (bufsize); + + if (!pwordexp) + /* Quoted - no field splitting */ + { + while (1) + { + if ((buflen = __read (fildes[0], buffer, bufsize)) < 1) + { + if (__waitpid (pid, &status, WNOHANG) == 0) + continue; + if ((buflen = __read (fildes[0], buffer, bufsize)) < 1) + break; + } + + maxnewlines += buflen; + + *word = w_addmem (*word, word_length, max_length, buffer, buflen); + if (*word == NULL) + goto no_space; + } + } + else + /* Not quoted - split fields */ + { + int copying = 0; + /* 'copying' is: + * 0 when searching for first character in a field not IFS white space + * 1 when copying the text of a field + * 2 when searching for possible non-whitespace IFS + * 3 when searching for non-newline after copying field + */ + + while (1) + { + if ((buflen = __read (fildes[0], buffer, bufsize)) < 1) + { + if (__waitpid (pid, &status, WNOHANG) == 0) + continue; + if ((buflen = __read (fildes[0], buffer, bufsize)) < 1) + break; + } + + for (i = 0; i < buflen; ++i) + { + if (strchr (ifs, buffer[i]) != NULL) + { + /* Current character is IFS */ + if (strchr (ifs_white, buffer[i]) == NULL) + { + /* Current character is IFS but not whitespace */ + if (copying == 2) + { + /* current character + * | + * V + * eg: text<space><comma><space>moretext + * + * So, strip whitespace IFS (like at the start) + */ + copying = 0; + continue; + } + + copying = 0; + /* fall through and delimit field.. */ + } + else + { + if (buffer[i] == '\n') + { + /* Current character is (IFS) newline */ + + /* If copying a field, this is the end of it, + but maybe all that's left is trailing newlines. + So start searching for a non-newline. */ + if (copying == 1) + copying = 3; + + continue; + } + else + { + /* Current character is IFS white space, but + not a newline */ + + /* If not either copying a field or searching + for non-newline after a field, ignore it */ + if (copying != 1 && copying != 3) + continue; + + /* End of field (search for non-ws IFS afterwards) */ + copying = 2; + } + } + + /* First IFS white space (non-newline), or IFS non-whitespace. + * Delimit the field. Nulls are converted by w_addword. */ + if (w_addword (pwordexp, *word) == WRDE_NOSPACE) + goto no_space; + + *word = w_newword (word_length, max_length); + + maxnewlines = 0; + /* fall back round the loop.. */ + } + else + { + /* Not IFS character */ + + if (copying == 3) + { + /* Nothing but (IFS) newlines since the last field, + so delimit it here before starting new word */ + if (w_addword (pwordexp, *word) == WRDE_NOSPACE) + goto no_space; + + *word = w_newword (word_length, max_length); + } + + copying = 1; + + if (buffer[i] == '\n') /* happens if newline not in IFS */ + maxnewlines++; + else + maxnewlines = 0; + + *word = w_addchar (*word, word_length, max_length, + buffer[i]); + if (*word == NULL) + goto no_space; + } + } + } + } + + /* Chop off trailing newlines (required by POSIX.2) */ + /* Ensure we don't go back further than the beginning of the + substitution (i.e. remove maxnewlines bytes at most) */ + while (maxnewlines-- != 0 && + *word_length > 0 && (*word)[*word_length - 1] == '\n') + { + (*word)[--*word_length] = '\0'; + + /* If the last word was entirely newlines, turn it into a new word + * which can be ignored if there's nothing following it. */ + if (*word_length == 0) + { + free (*word); + *word = w_newword (word_length, max_length); + break; + } + } + + __close (fildes[0]); + + /* Check for syntax error (re-execute but with "-n" flag) */ + if (buflen < 1 && status != 0) + { + if ((pid = __fork ()) < 0) + { + /* Bad */ + return WRDE_NOSPACE; + } + + if (pid == 0) + { + fildes[0] = fildes[1] = -1; + exec_comm_child(comm, fildes, 0, 1); + } + + if (__waitpid (pid, &status, 0) == pid && status != 0) + return WRDE_SYNTAX; + } + + return 0; + +no_space: + __kill (pid, SIGKILL); + __waitpid (pid, NULL, 0); + __close (fildes[0]); + return WRDE_NOSPACE; +} + +static int +internal_function +parse_comm (char **word, size_t *word_length, size_t *max_length, + const char *words, size_t *offset, int flags, wordexp_t *pwordexp, + const char *ifs, const char *ifs_white) +{ + /* We are poised just after "$(" */ + int paren_depth = 1; + int error = 0; + int quoted = 0; /* 1 for singly-quoted, 2 for doubly-quoted */ + size_t comm_length; + size_t comm_maxlen; + char *comm = w_newword (&comm_length, &comm_maxlen); + + for (; words[*offset]; ++(*offset)) + { + switch (words[*offset]) + { + case '\'': + if (quoted == 0) + quoted = 1; + else if (quoted == 1) + quoted = 0; + + break; + + case '"': + if (quoted == 0) + quoted = 2; + else if (quoted == 2) + quoted = 0; + + break; + + case ')': + if (!quoted && --paren_depth == 0) + { + /* Go -- give script to the shell */ + if (comm) + { + error = exec_comm (comm, word, word_length, max_length, + flags, pwordexp, ifs, ifs_white); + free (comm); + } + + return error; + } + + /* This is just part of the script */ + break; + + case '(': + if (!quoted) + ++paren_depth; + } + + comm = w_addchar (comm, &comm_length, &comm_maxlen, words[*offset]); + if (comm == NULL) + return WRDE_NOSPACE; + } + + /* Premature end */ + if (comm) + free (comm); + + return WRDE_SYNTAX; +} + +static int +internal_function +parse_param (char **word, size_t *word_length, size_t *max_length, + const char *words, size_t *offset, int flags, wordexp_t *pwordexp, + const char *ifs, const char *ifs_white, int quoted) +{ + /* We are poised just after "$" */ + enum action + { + ACT_NONE, + ACT_RP_SHORT_LEFT = '#', + ACT_RP_LONG_LEFT = 'L', + ACT_RP_SHORT_RIGHT = '%', + ACT_RP_LONG_RIGHT = 'R', + ACT_NULL_ERROR = '?', + ACT_NULL_SUBST = '-', + ACT_NONNULL_SUBST = '+', + ACT_NULL_ASSIGN = '=' + }; + size_t env_length; + size_t env_maxlen; + size_t pat_length; + size_t pat_maxlen; + size_t start = *offset; + char *env; + char *pattern; + char *value = NULL; + enum action action = ACT_NONE; + int depth = 0; + int colon_seen = 0; + int seen_hash = 0; + int free_value = 0; + int pattern_is_quoted = 0; /* 1 for singly-quoted, 2 for doubly-quoted */ + int error; + int special = 0; + char buffer[21]; + int brace = words[*offset] == '{'; + + env = w_newword (&env_length, &env_maxlen); + pattern = w_newword (&pat_length, &pat_maxlen); + + if (brace) + ++*offset; + + /* First collect the parameter name. */ + + if (words[*offset] == '#') + { + seen_hash = 1; + if (!brace) + goto envsubst; + ++*offset; + } + + if (isalpha (words[*offset]) || words[*offset] == '_') + { + /* Normal parameter name. */ + do + { + env = w_addchar (env, &env_length, &env_maxlen, + words[*offset]); + if (env == NULL) + goto no_space; + } + while (isalnum (words[++*offset]) || words[*offset] == '_'); + } + else if (isdigit (words[*offset])) + { + /* Numeric parameter name. */ + special = 1; + do + { + env = w_addchar (env, &env_length, &env_maxlen, + words[*offset]); + if (env == NULL) + goto no_space; + if (!brace) + goto envsubst; + } + while (isdigit(words[++*offset])); + } + else if (strchr ("*@$", words[*offset]) != NULL) + { + /* Special parameter. */ + special = 1; + env = w_addchar (env, &env_length, &env_maxlen, + words[*offset]); + if (env == NULL) + goto no_space; + ++*offset; + } + else + { + if (brace) + goto syntax; + } + + if (brace) + { + /* Check for special action to be applied to the value. */ + switch (words[*offset]) + { + case '}': + /* Evaluate. */ + goto envsubst; + + case '#': + action = ACT_RP_SHORT_LEFT; + if (words[1 + *offset] == '#') + { + ++*offset; + action = ACT_RP_LONG_LEFT; + } + break; + + case '%': + action = ACT_RP_SHORT_RIGHT; + if (words[1 + *offset] == '%') + { + ++*offset; + action = ACT_RP_LONG_RIGHT; + } + break; + + case ':': + if (strchr ("-=?+", words[1 + *offset]) == NULL) + goto syntax; + + colon_seen = 1; + action = words[++*offset]; + break; + + case '-': + case '=': + case '?': + case '+': + action = words[*offset]; + break; + + default: + goto syntax; + } + + /* Now collect the pattern, but don't expand it yet. */ + ++*offset; + for (; words[*offset]; ++(*offset)) + { + switch (words[*offset]) + { + case '{': + if (!pattern_is_quoted) + ++depth; + break; + + case '}': + if (!pattern_is_quoted) + { + if (depth == 0) + goto envsubst; + --depth; + } + break; + + case '\\': + if (pattern_is_quoted) + /* Quoted; treat as normal character. */ + break; + + /* Otherwise, it's an escape: next character is literal. */ + if (words[++*offset] == '\0') + goto syntax; + + pattern = w_addchar (pattern, &pat_length, &pat_maxlen, '\\'); + if (pattern == NULL) + goto no_space; + + break; + + case '\'': + if (pattern_is_quoted == 0) + pattern_is_quoted = 1; + else if (pattern_is_quoted == 1) + pattern_is_quoted = 0; + + break; + + case '"': + if (pattern_is_quoted == 0) + pattern_is_quoted = 2; + else if (pattern_is_quoted == 2) + pattern_is_quoted = 0; + + break; + } + + pattern = w_addchar (pattern, &pat_length, &pat_maxlen, + words[*offset]); + if (pattern == NULL) + goto no_space; + } + } + + /* End of input string -- remember to reparse the character that we + * stopped at. */ + --(*offset); + +envsubst: + if (words[start] == '{' && words[*offset] != '}') + goto syntax; + + if (env == NULL) + { + if (seen_hash) + { + /* $# expands to the number of positional parameters */ + buffer[20] = '\0'; + value = _itoa_word (__libc_argc - 1, &buffer[20], 10, 0); + seen_hash = 0; + } + else + { + /* Just $ on its own */ + *offset = start - 1; + *word = w_addchar (*word, word_length, max_length, '$'); + return *word ? 0 : WRDE_NOSPACE; + } + } + /* Is it a numeric parameter? */ + else if (isdigit (env[0])) + { + int n = atoi (env); + + if (n >= __libc_argc) + /* Substitute NULL. */ + value = NULL; + else + /* Replace with appropriate positional parameter. */ + value = __libc_argv[n]; + } + /* Is it a special parameter? */ + else if (special) + { + /* Is it `$$'? */ + if (*env == '$') + { + buffer[20] = '\0'; + value = _itoa_word (__getpid (), &buffer[20], 10, 0); + } + /* Is it `${#*}' or `${#@}'? */ + else if ((*env == '*' || *env == '@') && seen_hash) + { + buffer[20] = '\0'; + value = _itoa_word (__libc_argc > 0 ? __libc_argc - 1 : 0, + &buffer[20], 10, 0); + *word = w_addstr (*word, word_length, max_length, value); + free (env); + if (pattern) + free (pattern); + return *word ? 0 : WRDE_NOSPACE; + } + /* Is it `$*' or `$@' (unquoted) ? */ + else if (*env == '*' || (*env == '@' && !quoted)) + { + size_t plist_len = 0; + int p; + char *end; + + /* Build up value parameter by parameter (copy them) */ + for (p = 1; __libc_argv[p]; ++p) + plist_len += strlen (__libc_argv[p]) + 1; /* for space */ + value = malloc (plist_len); + if (value == NULL) + goto no_space; + end = value; + *end = 0; + for (p = 1; __libc_argv[p]; ++p) + { + if (p > 1) + *end++ = ' '; + end = __stpcpy (end, __libc_argv[p]); + } + + free_value = 1; + } + else + { + /* Must be a quoted `$@' */ + assert (*env == '@' && quoted); + + /* Each parameter is a separate word ("$@") */ + if (__libc_argc == 2) + value = __libc_argv[1]; + else if (__libc_argc > 2) + { + int p; + + /* Append first parameter to current word. */ + value = w_addstr (*word, word_length, max_length, + __libc_argv[1]); + if (value == NULL || w_addword (pwordexp, value)) + goto no_space; + + for (p = 2; __libc_argv[p + 1]; p++) + { + char *newword = __strdup (__libc_argv[p]); + if (newword == NULL || w_addword (pwordexp, newword)) + goto no_space; + } + + /* Start a new word with the last parameter. */ + *word = w_newword (word_length, max_length); + value = __libc_argv[p]; + } + else + { + free (env); + free (pattern); + return 0; + } + } + } + else + value = getenv (env); + + if (value == NULL && (flags & WRDE_UNDEF)) + { + /* Variable not defined. */ + error = WRDE_BADVAL; + goto do_error; + } + + if (action != ACT_NONE) + { + int expand_pattern = 0; + + /* First, find out if we need to expand pattern (i.e. if we will + * use it). */ + switch (action) + { + case ACT_RP_SHORT_LEFT: + case ACT_RP_LONG_LEFT: + case ACT_RP_SHORT_RIGHT: + case ACT_RP_LONG_RIGHT: + /* Always expand for these. */ + expand_pattern = 1; + break; + + case ACT_NULL_ERROR: + case ACT_NULL_SUBST: + case ACT_NULL_ASSIGN: + if (!value || (!*value && colon_seen)) + /* If param is unset, or set but null and a colon has been seen, + the expansion of the pattern will be needed. */ + expand_pattern = 1; + + break; + + case ACT_NONNULL_SUBST: + /* Expansion of word will be needed if parameter is set and not null, + or set null but no colon has been seen. */ + if (value && (*value || !colon_seen)) + expand_pattern = 1; + + break; + + default: + assert (! "Unrecognised action!"); + } + + if (expand_pattern) + { + /* We need to perform tilde expansion, parameter expansion, + command substitution, and arithmetic expansion. We also + have to be a bit careful with wildcard characters, as + pattern might be given to fnmatch soon. To do this, we + convert quotes to escapes. */ + + char *expanded; + size_t exp_len; + size_t exp_maxl; + char *p; + int quoted = 0; /* 1: single quotes; 2: double */ + + expanded = w_newword (&exp_len, &exp_maxl); + for (p = pattern; p && *p; p++) + { + size_t offset; + + switch (*p) + { + case '"': + if (quoted == 2) + quoted = 0; + else if (quoted == 0) + quoted = 2; + else break; + + continue; + + case '\'': + if (quoted == 1) + quoted = 0; + else if (quoted == 0) + quoted = 1; + else break; + + continue; + + case '*': + case '?': + if (quoted) + { + /* Convert quoted wildchar to escaped wildchar. */ + expanded = w_addchar (expanded, &exp_len, + &exp_maxl, '\\'); + + if (expanded == NULL) + goto no_space; + } + break; + + case '$': + offset = 0; + error = parse_dollars (&expanded, &exp_len, &exp_maxl, p, + &offset, flags, NULL, NULL, NULL, 1); + if (error) + { + if (free_value) + free (value); + + if (expanded) + free (expanded); + + goto do_error; + } + + p += offset; + continue; + + case '~': + if (quoted || exp_len) + break; + + offset = 0; + error = parse_tilde (&expanded, &exp_len, &exp_maxl, p, + &offset, 0); + if (error) + { + if (free_value) + free (value); + + if (expanded) + free (expanded); + + goto do_error; + } + + p += offset; + continue; + + case '\\': + expanded = w_addchar (expanded, &exp_len, &exp_maxl, '\\'); + ++p; + assert (*p); /* checked when extracted initially */ + if (expanded == NULL) + goto no_space; + } + + expanded = w_addchar (expanded, &exp_len, &exp_maxl, *p); + + if (expanded == NULL) + goto no_space; + } + + if (pattern) + free (pattern); + + pattern = expanded; + } + + switch (action) + { + case ACT_RP_SHORT_LEFT: + case ACT_RP_LONG_LEFT: + case ACT_RP_SHORT_RIGHT: + case ACT_RP_LONG_RIGHT: + { + char *p; + char c; + char *end; + + if (value == NULL || pattern == NULL || *pattern == '\0') + break; + + end = value + strlen (value); + + switch (action) + { + case ACT_RP_SHORT_LEFT: + for (p = value; p <= end; ++p) + { + c = *p; + *p = '\0'; + if (fnmatch (pattern, value, 0) != FNM_NOMATCH) + { + *p = c; + if (free_value) + { + char *newval = __strdup (p); + if (newval == NULL) + { + free (value); + goto no_space; + } + free (value); + value = newval; + } + else + value = p; + break; + } + *p = c; + } + + break; + + case ACT_RP_LONG_LEFT: + for (p = end; p >= value; --p) + { + c = *p; + *p = '\0'; + if (fnmatch (pattern, value, 0) != FNM_NOMATCH) + { + *p = c; + if (free_value) + { + char *newval = __strdup (p); + if (newval == NULL) + { + free (value); + goto no_space; + } + free (value); + value = newval; + } + else + value = p; + break; + } + *p = c; + } + + break; + + case ACT_RP_SHORT_RIGHT: + for (p = end; p >= value; --p) + { + if (fnmatch (pattern, p, 0) != FNM_NOMATCH) + { + char *newval; + newval = malloc (p - value + 1); + + if (newval == NULL) + { + if (free_value) + free (value); + goto no_space; + } + + *(char *) __mempcpy (newval, value, p - value) = '\0'; + if (free_value) + free (value); + value = newval; + free_value = 1; + break; + } + } + + break; + + case ACT_RP_LONG_RIGHT: + for (p = value; p <= end; ++p) + { + if (fnmatch (pattern, p, 0) != FNM_NOMATCH) + { + char *newval; + newval = malloc (p - value + 1); + + if (newval == NULL) + { + if (free_value) + free (value); + goto no_space; + } + + *(char *) __mempcpy (newval, value, p - value) = '\0'; + if (free_value) + free (value); + value = newval; + free_value = 1; + break; + } + } + + break; + + default: + break; + } + + break; + } + + case ACT_NULL_ERROR: + if (value && *value) + /* Substitute parameter */ + break; + + error = 0; + if (!colon_seen && value) + /* Substitute NULL */ + ; + else if (*pattern) + fprintf (stderr, "%s: %s\n", env, pattern); + else + { + fprintf (stderr, "%s: parameter null or not set\n", env); + error = WRDE_BADVAL; + } + + if (free_value) + free (value); + goto do_error; + + case ACT_NULL_SUBST: + if (value && *value) + /* Substitute parameter */ + break; + + if (free_value && value) + free (value); + + if (!colon_seen && value) + /* Substitute NULL */ + goto success; + + value = pattern ? __strdup (pattern) : pattern; + free_value = 1; + + if (pattern && !value) + goto no_space; + + break; + + case ACT_NONNULL_SUBST: + if (value && (*value || !colon_seen)) + { + if (free_value && value) + free (value); + + value = pattern ? __strdup (pattern) : pattern; + free_value = 1; + + if (pattern && !value) + goto no_space; + + break; + } + + /* Substitute NULL */ + if (free_value) + free (value); + goto success; + + case ACT_NULL_ASSIGN: + if (value && *value) + /* Substitute parameter */ + break; + + if (!colon_seen && value) + { + /* Substitute NULL */ + if (free_value) + free (value); + goto success; + } + + if (free_value && value) + free (value); + + value = pattern ? __strdup (pattern) : pattern; + free_value = 1; + + if (pattern && !value) + goto no_space; + + __setenv (env, value, 1); + break; + + default: + assert (! "Unrecognised action!"); + } + } + + free (env); env = NULL; + free (pattern); pattern = NULL; + + if (seen_hash) + { + char param_length[21]; + param_length[20] = '\0'; + *word = w_addstr (*word, word_length, max_length, + _itoa_word (value ? strlen (value) : 0, + ¶m_length[20], 10, 0)); + if (free_value) + { + assert (value != NULL); + free (value); + } + + return *word ? 0 : WRDE_NOSPACE; + } + + if (value == NULL) + return 0; + + if (quoted || !pwordexp) + { + /* Quoted - no field split */ + *word = w_addstr (*word, word_length, max_length, value); + if (free_value) + free (value); + + return *word ? 0 : WRDE_NOSPACE; + } + else + { + /* Need to field-split */ + char *value_copy = __strdup (value); /* Don't modify value */ + char *field_begin = value_copy; + int seen_nonws_ifs = 0; + + if (free_value) + free (value); + + if (value_copy == NULL) + goto no_space; + + do + { + char *field_end = field_begin; + char *next_field; + + /* If this isn't the first field, start a new word */ + if (field_begin != value_copy) + { + if (w_addword (pwordexp, *word) == WRDE_NOSPACE) + { + free (value_copy); + goto no_space; + } + + *word = w_newword (word_length, max_length); + } + + /* Skip IFS whitespace before the field */ + field_begin += strspn (field_begin, ifs_white); + + if (!seen_nonws_ifs && *field_begin == 0) + /* Nothing but whitespace */ + break; + + /* Search for the end of the field */ + field_end = field_begin + strcspn (field_begin, ifs); + + /* Set up pointer to the character after end of field and + skip whitespace IFS after it. */ + next_field = field_end + strspn (field_end, ifs_white); + + /* Skip at most one non-whitespace IFS character after the field */ + seen_nonws_ifs = 0; + if (*next_field && strchr (ifs, *next_field)) + { + seen_nonws_ifs = 1; + next_field++; + } + + /* Null-terminate it */ + *field_end = 0; + + /* Tag a copy onto the current word */ + *word = w_addstr (*word, word_length, max_length, field_begin); + + if (*word == NULL && *field_begin != '\0') + { + free (value_copy); + goto no_space; + } + + field_begin = next_field; + } + while (seen_nonws_ifs || *field_begin); + + free (value_copy); + } + + return 0; + +success: + error = 0; + goto do_error; + +no_space: + error = WRDE_NOSPACE; + goto do_error; + +syntax: + error = WRDE_SYNTAX; + +do_error: + if (env) + free (env); + + if (pattern) + free (pattern); + + return error; +} + +static int +internal_function +parse_dollars (char **word, size_t *word_length, size_t *max_length, + const char *words, size_t *offset, int flags, + wordexp_t *pwordexp, const char *ifs, const char *ifs_white, + int quoted) +{ + /* We are poised _at_ "$" */ + switch (words[1 + *offset]) + { + case '"': + case '\'': + case 0: + *word = w_addchar (*word, word_length, max_length, '$'); + return *word ? 0 : WRDE_NOSPACE; + + case '(': + if (words[2 + *offset] == '(') + { + /* Differentiate between $((1+3)) and $((echo);(ls)) */ + int i = 3 + *offset; + int depth = 0; + while (words[i] && !(depth == 0 && words[i] == ')')) + { + if (words[i] == '(') + ++depth; + else if (words[i] == ')') + --depth; + + ++i; + } + + if (words[i] == ')' && words[i + 1] == ')') + { + (*offset) += 3; + /* Call parse_arith -- 0 is for "no brackets" */ + return parse_arith (word, word_length, max_length, words, offset, + flags, 0); + } + } + + if (flags & WRDE_NOCMD) + return WRDE_CMDSUB; + + (*offset) += 2; + return parse_comm (word, word_length, max_length, words, offset, flags, + quoted? NULL : pwordexp, ifs, ifs_white); + + case '[': + (*offset) += 2; + /* Call parse_arith -- 1 is for "brackets" */ + return parse_arith (word, word_length, max_length, words, offset, flags, + 1); + + case '{': + default: + ++(*offset); /* parse_param needs to know if "{" is there */ + return parse_param (word, word_length, max_length, words, offset, flags, + pwordexp, ifs, ifs_white, quoted); + } +} + +static int +internal_function +parse_backtick (char **word, size_t *word_length, size_t *max_length, + const char *words, size_t *offset, int flags, + wordexp_t *pwordexp, const char *ifs, const char *ifs_white) +{ + /* We are poised just after "`" */ + int error; + int squoting = 0; + size_t comm_length; + size_t comm_maxlen; + char *comm = w_newword (&comm_length, &comm_maxlen); + + for (; words[*offset]; ++(*offset)) + { + switch (words[*offset]) + { + case '`': + /* Go -- give the script to the shell */ + error = exec_comm (comm, word, word_length, max_length, flags, + pwordexp, ifs, ifs_white); + free (comm); + return error; + + case '\\': + if (squoting) + { + error = parse_qtd_backslash (&comm, &comm_length, &comm_maxlen, + words, offset); + + if (error) + { + free (comm); + return error; + } + + break; + } + + ++(*offset); + error = parse_backslash (&comm, &comm_length, &comm_maxlen, words, + offset); + + if (error) + { + free (comm); + return error; + } + + break; + + case '\'': + squoting = 1 - squoting; + default: + comm = w_addchar (comm, &comm_length, &comm_maxlen, words[*offset]); + if (comm == NULL) + return WRDE_NOSPACE; + } + } + + /* Premature end */ + free (comm); + return WRDE_SYNTAX; +} + +static int +internal_function +parse_dquote (char **word, size_t *word_length, size_t *max_length, + const char *words, size_t *offset, int flags, + wordexp_t *pwordexp, const char * ifs, const char * ifs_white) +{ + /* We are poised just after a double-quote */ + int error; + + for (; words[*offset]; ++(*offset)) + { + switch (words[*offset]) + { + case '"': + return 0; + + case '$': + error = parse_dollars (word, word_length, max_length, words, offset, + flags, pwordexp, ifs, ifs_white, 1); + /* The ``1'' here is to tell parse_dollars not to + * split the fields. It may need to, however ("$@"). + */ + if (error) + return error; + + break; + + case '`': + if (flags & WRDE_NOCMD) + return WRDE_CMDSUB; + + ++(*offset); + error = parse_backtick (word, word_length, max_length, words, + offset, flags, NULL, NULL, NULL); + /* The first NULL here is to tell parse_backtick not to + * split the fields. + */ + if (error) + return error; + + break; + + case '\\': + error = parse_qtd_backslash (word, word_length, max_length, words, + offset); + + if (error) + return error; + + break; + + default: + *word = w_addchar (*word, word_length, max_length, words[*offset]); + if (*word == NULL) + return WRDE_NOSPACE; + } + } + + /* Unterminated string */ + return WRDE_SYNTAX; +} + +/* + * wordfree() is to be called after pwordexp is finished with. + */ + +void +wordfree (wordexp_t *pwordexp) +{ + + /* wordexp can set pwordexp to NULL */ + if (pwordexp && pwordexp->we_wordv) + { + char **wordv = pwordexp->we_wordv; + + for (wordv += pwordexp->we_offs; *wordv; ++wordv) + free (*wordv); + + free (pwordexp->we_wordv); + pwordexp->we_wordv = NULL; + } +} + +/* + * wordexp() + */ + +int +wordexp (const char *words, wordexp_t *pwordexp, int flags) +{ + size_t words_offset; + size_t word_length; + size_t max_length; + char *word = w_newword (&word_length, &max_length); + int error; + char *ifs; + char ifs_white[4]; + wordexp_t old_word = *pwordexp; + + if (flags & WRDE_REUSE) + { + /* Minimal implementation of WRDE_REUSE for now */ + wordfree (pwordexp); + old_word.we_wordv = NULL; + } + + if ((flags & WRDE_APPEND) == 0) + { + pwordexp->we_wordc = 0; + + if (flags & WRDE_DOOFFS) + { + pwordexp->we_wordv = calloc (1 + pwordexp->we_offs, sizeof (char *)); + if (pwordexp->we_wordv == NULL) + { + error = WRDE_NOSPACE; + goto do_error; + } + } + else + { + pwordexp->we_wordv = calloc (1, sizeof (char *)); + if (pwordexp->we_wordv == NULL) + { + error = WRDE_NOSPACE; + goto do_error; + } + + pwordexp->we_offs = 0; + } + } + + /* Find out what the field separators are. + * There are two types: whitespace and non-whitespace. + */ + ifs = getenv ("IFS"); + + if (!ifs) + /* IFS unset - use <space><tab><newline>. */ + ifs = strcpy (ifs_white, " \t\n"); + else + { + char *ifsch = ifs; + char *whch = ifs_white; + + /* Start off with no whitespace IFS characters */ + ifs_white[0] = '\0'; + + while (*ifsch != '\0') + { + if ((*ifsch == ' ') || (*ifsch == '\t') || (*ifsch == '\n')) + { + /* Whitespace IFS. See first whether it is already in our + collection. */ + char *runp = ifs_white; + + while (runp < whch && *runp != '\0' && *runp != *ifsch) + ++runp; + + if (runp == whch) + *whch++ = *ifsch; + } + + ++ifsch; + } + *whch = '\0'; + } + + for (words_offset = 0 ; words[words_offset] ; ++words_offset) + switch (words[words_offset]) + { + case '\\': + error = parse_backslash (&word, &word_length, &max_length, words, + &words_offset); + + if (error) + goto do_error; + + break; + + case '$': + error = parse_dollars (&word, &word_length, &max_length, words, + &words_offset, flags, pwordexp, ifs, ifs_white, + 0); + + if (error) + goto do_error; + + break; + + case '`': + if (flags & WRDE_NOCMD) + { + error = WRDE_CMDSUB; + goto do_error; + } + + ++words_offset; + error = parse_backtick (&word, &word_length, &max_length, words, + &words_offset, flags, pwordexp, ifs, + ifs_white); + + if (error) + goto do_error; + + break; + + case '"': + ++words_offset; + error = parse_dquote (&word, &word_length, &max_length, words, + &words_offset, flags, pwordexp, ifs, ifs_white); + + if (error) + goto do_error; + + if (!word_length) + { + error = w_addword (pwordexp, NULL); + + if (error) + return error; + } + + break; + + case '\'': + ++words_offset; + error = parse_squote (&word, &word_length, &max_length, words, + &words_offset); + + if (error) + goto do_error; + + if (!word_length) + { + error = w_addword (pwordexp, NULL); + + if (error) + return error; + } + + break; + + case '~': + error = parse_tilde (&word, &word_length, &max_length, words, + &words_offset, pwordexp->we_wordc); + + if (error) + goto do_error; + + break; + + case '*': + case '[': + case '?': + error = parse_glob (&word, &word_length, &max_length, words, + &words_offset, flags, pwordexp, ifs, ifs_white); + + if (error) + goto do_error; + + break; + + default: + /* Is it a word separator? */ + if (strchr (" \t", words[words_offset]) == NULL) + { + char ch = words[words_offset]; + + /* Not a word separator -- but is it a valid word char? */ + if (strchr ("\n|&;<>(){}", ch)) + { + /* Fail */ + error = WRDE_BADCHAR; + goto do_error; + } + + /* "Ordinary" character -- add it to word */ + word = w_addchar (word, &word_length, &max_length, + ch); + if (word == NULL) + { + error = WRDE_NOSPACE; + goto do_error; + } + + break; + } + + /* If a word has been delimited, add it to the list. */ + if (word != NULL) + { + error = w_addword (pwordexp, word); + if (error) + goto do_error; + } + + word = w_newword (&word_length, &max_length); + } + + /* End of string */ + + /* There was a word separator at the end */ + if (word == NULL) /* i.e. w_newword */ + return 0; + + /* There was no field separator at the end */ + return w_addword (pwordexp, word); + +do_error: + /* Error: + * free memory used (unless error is WRDE_NOSPACE), and + * set pwordexp members back to what they were. + */ + + if (word != NULL) + free (word); + + if (error == WRDE_NOSPACE) + return WRDE_NOSPACE; + + if ((flags & WRDE_APPEND) == 0) + wordfree (pwordexp); + + *pwordexp = old_word; + return error; +} |