2 * Copyright (c) 2002 Tim J. Robbins.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 #include "namespace.h"
28 #include <sys/cdefs.h>
29 #include <sys/types.h>
38 #include "un-namespace.h"
40 __FBSDID("$FreeBSD$");
42 static int we_askshell(const char *, wordexp_t *, int);
43 static int we_check(const char *, int);
47 * Perform shell word expansion on `words' and place the resulting list
48 * of words in `we'. See wordexp(3).
50 * Specified by IEEE Std. 1003.1-2001.
53 wordexp(const char * __restrict words, wordexp_t * __restrict we, int flags)
57 if (flags & WRDE_REUSE)
59 if ((flags & WRDE_APPEND) == 0) {
62 we->we_strings = NULL;
65 if ((error = we_check(words, flags)) != 0) {
69 if ((error = we_askshell(words, we, flags)) != 0) {
78 * Use the `wordexp' /bin/sh builtin function to do most of the work
79 * in expanding the word string. This function is complicated by
83 we_askshell(const char *words, wordexp_t *we, int flags)
85 int pdes[2]; /* Pipe to child */
86 char bbuf[9]; /* Buffer for byte count */
87 char wbuf[9]; /* Buffer for word count */
88 long nwords, nbytes; /* Number of words, bytes from child */
89 long i; /* Handy integer */
90 size_t sofs; /* Offset into we->we_strings */
91 size_t vofs; /* Offset into we->we_wordv */
92 pid_t pid; /* Process ID of child */
93 int status; /* Child exit status */
94 char *ifs; /* IFS env. var. */
95 char *np, *p; /* Handy pointers */
96 char *nstrings; /* Temporary for realloc() */
97 char **nwv; /* Temporary for realloc() */
99 if ((ifs = getenv("IFS")) == NULL)
103 return (WRDE_NOSPACE); /* XXX */
104 if ((pid = fork()) < 0) {
107 return (WRDE_NOSPACE); /* XXX */
111 * We are the child; just get /bin/sh to run the wordexp
112 * builtin on `words'.
118 if (_dup2(pdes[1], STDOUT_FILENO) < 0)
121 if (asprintf(&cmd, "wordexp%c%s\n", *ifs, words) < 0)
123 if ((flags & WRDE_SHOWERR) == 0) {
124 if ((devnull = _open(_PATH_DEVNULL, O_RDWR, 0666)) < 0)
126 if (_dup2(devnull, STDERR_FILENO) < 0)
130 execl(_PATH_BSHELL, "sh", flags & WRDE_UNDEF ? "-u" : "+u",
131 "-c", cmd, (char *)NULL);
136 * We are the parent; read the output of the shell wordexp function,
137 * which is a 32-bit hexadecimal word count, a 32-bit hexadecimal
138 * byte count (not including terminating null bytes), followed by
139 * the expanded words separated by nulls.
142 if (_read(pdes[0], wbuf, 8) != 8 || _read(pdes[0], bbuf, 8) != 8) {
144 _waitpid(pid, &status, 0);
145 return (flags & WRDE_UNDEF ? WRDE_BADVAL : WRDE_SYNTAX);
147 wbuf[8] = bbuf[8] = '\0';
148 nwords = strtol(wbuf, NULL, 16);
149 nbytes = strtol(bbuf, NULL, 16) + nwords;
152 * Allocate or reallocate (when flags & WRDE_APPEND) the word vector
153 * and string storage buffers for the expanded words we're about to
154 * read from the child.
156 sofs = we->we_nbytes;
158 if ((flags & (WRDE_DOOFFS|WRDE_APPEND)) == (WRDE_DOOFFS|WRDE_APPEND))
160 we->we_wordc += nwords;
161 we->we_nbytes += nbytes;
162 if ((nwv = realloc(we->we_wordv, (we->we_wordc + 1 +
163 (flags & WRDE_DOOFFS ? we->we_offs : 0)) *
164 sizeof(char *))) == NULL) {
166 _waitpid(pid, &status, 0);
167 return (WRDE_NOSPACE);
170 if ((nstrings = realloc(we->we_strings, we->we_nbytes)) == NULL) {
172 _waitpid(pid, &status, 0);
173 return (WRDE_NOSPACE);
175 for (i = 0; i < vofs; i++)
176 if (we->we_wordv[i] != NULL)
177 we->we_wordv[i] += nstrings - we->we_strings;
178 we->we_strings = nstrings;
180 if (_read(pdes[0], we->we_strings + sofs, nbytes) != nbytes) {
182 _waitpid(pid, &status, 0);
183 return (flags & WRDE_UNDEF ? WRDE_BADVAL : WRDE_SYNTAX);
186 if (_waitpid(pid, &status, 0) < 0 || !WIFEXITED(status) ||
187 WEXITSTATUS(status) != 0) {
189 return (flags & WRDE_UNDEF ? WRDE_BADVAL : WRDE_SYNTAX);
194 * Break the null-terminated expanded word strings out into
197 if (vofs == 0 && flags & WRDE_DOOFFS)
198 while (vofs < we->we_offs)
199 we->we_wordv[vofs++] = NULL;
200 p = we->we_strings + sofs;
201 while (nwords-- != 0) {
202 we->we_wordv[vofs++] = p;
203 if ((np = memchr(p, '\0', nbytes)) == NULL)
204 return (WRDE_NOSPACE); /* XXX */
205 nbytes -= np - p + 1;
208 we->we_wordv[vofs] = NULL;
215 * Check that the string contains none of the following unquoted
216 * special characters: <newline> |&;<>(){}
217 * or command substitutions when WRDE_NOCMD is set in flags.
220 we_check(const char *words, int flags)
223 int dquote, level, quote, squote;
225 quote = squote = dquote = 0;
226 while ((c = *words++) != '\0') {
232 if (quote + dquote == 0)
236 if (quote + squote == 0)
240 if (quote + squote == 0 && flags & WRDE_NOCMD)
241 return (WRDE_CMDSUB);
242 while ((c = *words++) != '\0' && c != '`')
243 if (c == '\\' && (c = *words++) == '\0')
246 return (WRDE_SYNTAX);
248 case '|': case '&': case ';': case '<': case '>':
249 case '{': case '}': case '(': case ')': case '\n':
250 if (quote + squote + dquote == 0)
251 return (WRDE_BADCHAR);
254 if ((c = *words++) == '\0')
256 else if (quote + squote == 0 && c == '(') {
257 if (flags & WRDE_NOCMD && *words != '(')
258 return (WRDE_CMDSUB);
260 while ((c = *words++) != '\0') {
262 if ((c = *words++) == '\0')
266 else if (c == ')' && --level == 0)
269 if (c == '\0' || level != 0)
270 return (WRDE_SYNTAX);
271 } else if (quote + squote == 0 && c == '{') {
273 while ((c = *words++) != '\0') {
275 if ((c = *words++) == '\0')
279 else if (c == '}' && --level == 0)
282 if (c == '\0' || level != 0)
283 return (WRDE_SYNTAX);
292 if (quote + squote + dquote != 0)
293 return (WRDE_SYNTAX);
300 * Free the result of wordexp(). See wordexp(3).
302 * Specified by IEEE Std. 1003.1-2001.
305 wordfree(wordexp_t *we)
311 free(we->we_strings);
313 we->we_strings = NULL;