master
  1#define _BSD_SOURCE
  2#include <glob.h>
  3#include <fnmatch.h>
  4#include <sys/stat.h>
  5#include <dirent.h>
  6#include <limits.h>
  7#include <string.h>
  8#include <stdlib.h>
  9#include <errno.h>
 10#include <stddef.h>
 11#include <unistd.h>
 12#include <pwd.h>
 13
 14struct match
 15{
 16	struct match *next;
 17	char name[];
 18};
 19
 20static int append(struct match **tail, const char *name, size_t len, int mark)
 21{
 22	struct match *new = malloc(sizeof(struct match) + len + 2);
 23	if (!new) return -1;
 24	(*tail)->next = new;
 25	new->next = NULL;
 26	memcpy(new->name, name, len+1);
 27	if (mark && len && name[len-1]!='/') {
 28		new->name[len] = '/';
 29		new->name[len+1] = 0;
 30	}
 31	*tail = new;
 32	return 0;
 33}
 34
 35static int do_glob(char *buf, size_t pos, int type, char *pat, int flags, int (*errfunc)(const char *path, int err), struct match **tail)
 36{
 37	/* If GLOB_MARK is unused, we don't care about type. */
 38	if (!type && !(flags & GLOB_MARK)) type = DT_REG;
 39
 40	/* Special-case the remaining pattern being all slashes, in
 41	 * which case we can use caller-passed type if it's a dir. */
 42	if (*pat && type!=DT_DIR) type = 0;
 43	while (pos+1 < PATH_MAX && *pat=='/') buf[pos++] = *pat++;
 44
 45	/* Consume maximal [escaped-]literal prefix of pattern, copying
 46	 * and un-escaping it to the running buffer as we go. */
 47	ptrdiff_t i=0, j=0;
 48	int in_bracket = 0, overflow = 0;
 49	for (; pat[i]!='*' && pat[i]!='?' && (!in_bracket || pat[i]!=']'); i++) {
 50		if (!pat[i]) {
 51			if (overflow) return 0;
 52			pat += i;
 53			pos += j;
 54			i = j = 0;
 55			break;
 56		} else if (pat[i] == '[') {
 57			in_bracket = 1;
 58		} else if (pat[i] == '\\' && !(flags & GLOB_NOESCAPE)) {
 59			/* Backslashes inside a bracket are (at least by
 60			 * our interpretation) non-special, so if next
 61			 * char is ']' we have a complete expression. */
 62			if (in_bracket && pat[i+1]==']') break;
 63			/* Unpaired final backslash never matches. */
 64			if (!pat[i+1]) return 0;
 65			i++;
 66		}
 67		if (pat[i] == '/') {
 68			if (overflow) return 0;
 69			in_bracket = 0;
 70			pat += i+1;
 71			i = -1;
 72			pos += j+1;
 73			j = -1;
 74		}
 75		/* Only store a character if it fits in the buffer, but if
 76		 * a potential bracket expression is open, the overflow
 77		 * must be remembered and handled later only if the bracket
 78		 * is unterminated (and thereby a literal), so as not to
 79		 * disallow long bracket expressions with short matches. */
 80		if (pos+(j+1) < PATH_MAX) {
 81			buf[pos+j++] = pat[i];
 82		} else if (in_bracket) {
 83			overflow = 1;
 84		} else {
 85			return 0;
 86		}
 87		/* If we consume any new components, the caller-passed type
 88		 * or dummy type from above is no longer valid. */
 89		type = 0;
 90	}
 91	buf[pos] = 0;
 92	if (!*pat) {
 93		/* If we consumed any components above, or if GLOB_MARK is
 94		 * requested and we don't yet know if the match is a dir,
 95		 * we must confirm the file exists and/or determine its type.
 96		 *
 97		 * If marking dirs, symlink type is inconclusive; we need the
 98		 * type for the symlink target, and therefore must try stat
 99		 * first unless type is known not to be a symlink. Otherwise,
100		 * or if that fails, use lstat for determining existence to
101		 * avoid false negatives in the case of broken symlinks. */
102		struct stat st;
103		if ((flags & GLOB_MARK) && (!type||type==DT_LNK) && !stat(buf, &st)) {
104			if (S_ISDIR(st.st_mode)) type = DT_DIR;
105			else type = DT_REG;
106		}
107		if (!type && lstat(buf, &st)) {
108			if (errno!=ENOENT && (errfunc(buf, errno) || (flags & GLOB_ERR)))
109				return GLOB_ABORTED;
110			return 0;
111		}
112		if (append(tail, buf, pos, (flags & GLOB_MARK) && type==DT_DIR))
113			return GLOB_NOSPACE;
114		return 0;
115	}
116	char *p2 = strchr(pat, '/'), saved_sep = '/';
117	/* Check if the '/' was escaped and, if so, remove the escape char
118	 * so that it will not be unpaired when passed to fnmatch. */
119	if (p2 && !(flags & GLOB_NOESCAPE)) {
120		char *p;
121		for (p=p2; p>pat && p[-1]=='\\'; p--);
122		if ((p2-p)%2) {
123			p2--;
124			saved_sep = '\\';
125		}
126	}
127	DIR *dir = opendir(pos ? buf : ".");
128	if (!dir) {
129		if (errfunc(buf, errno) || (flags & GLOB_ERR))
130			return GLOB_ABORTED;
131		return 0;
132	}
133	int old_errno = errno;
134	struct dirent *de;
135	while (errno=0, de=readdir(dir)) {
136		/* Quickly skip non-directories when there's pattern left. */
137		if (p2 && de->d_type && de->d_type!=DT_DIR && de->d_type!=DT_LNK)
138			continue;
139
140		size_t l = strlen(de->d_name);
141		if (l >= PATH_MAX-pos) continue;
142
143		if (p2) *p2 = 0;
144
145		int fnm_flags= ((flags & GLOB_NOESCAPE) ? FNM_NOESCAPE : 0)
146			| ((!(flags & GLOB_PERIOD)) ? FNM_PERIOD : 0);
147
148		if (fnmatch(pat, de->d_name, fnm_flags))
149			continue;
150
151		/* With GLOB_PERIOD, don't allow matching . or .. unless
152		 * fnmatch would match them with FNM_PERIOD rules in effect. */
153		if (p2 && (flags & GLOB_PERIOD) && de->d_name[0]=='.'
154		    && (!de->d_name[1] || de->d_name[1]=='.' && !de->d_name[2])
155		    && fnmatch(pat, de->d_name, fnm_flags | FNM_PERIOD))
156			continue;
157
158		memcpy(buf+pos, de->d_name, l+1);
159		if (p2) *p2 = saved_sep;
160		int r = do_glob(buf, pos+l, de->d_type, p2 ? p2 : "", flags, errfunc, tail);
161		if (r) {
162			closedir(dir);
163			return r;
164		}
165	}
166	int readerr = errno;
167	if (p2) *p2 = saved_sep;
168	closedir(dir);
169	if (readerr && (errfunc(buf, errno) || (flags & GLOB_ERR)))
170		return GLOB_ABORTED;
171	errno = old_errno;
172	return 0;
173}
174
175static int ignore_err(const char *path, int err)
176{
177	return 0;
178}
179
180static void freelist(struct match *head)
181{
182	struct match *match, *next;
183	for (match=head->next; match; match=next) {
184		next = match->next;
185		free(match);
186	}
187}
188
189static int sort(const void *a, const void *b)
190{
191	return strcmp(*(const char **)a, *(const char **)b);
192}
193
194static int expand_tilde(char **pat, char *buf, size_t *pos)
195{
196	char *p = *pat + 1;
197	size_t i = 0;
198
199	char delim, *name_end = __strchrnul(p, '/');
200	if ((delim = *name_end)) *name_end++ = 0;
201	*pat = name_end;
202
203	char *home = *p ? NULL : getenv("HOME");
204	if (!home) {
205		struct passwd pw, *res;
206		switch (*p ? getpwnam_r(p, &pw, buf, PATH_MAX, &res)
207			   : getpwuid_r(getuid(), &pw, buf, PATH_MAX, &res)) {
208		case ENOMEM:
209			return GLOB_NOSPACE;
210		case 0:
211			if (!res)
212		default:
213				return GLOB_NOMATCH;
214		}
215		home = pw.pw_dir;
216	}
217	while (i < PATH_MAX - 2 && *home)
218		buf[i++] = *home++;
219	if (*home)
220		return GLOB_NOMATCH;
221	if ((buf[i] = delim))
222		buf[++i] = 0;
223	*pos = i;
224	return 0;
225}
226
227int glob(const char *restrict pat, int flags, int (*errfunc)(const char *path, int err), glob_t *restrict g)
228{
229	struct match head = { .next = NULL }, *tail = &head;
230	size_t cnt, i;
231	size_t offs = (flags & GLOB_DOOFFS) ? g->gl_offs : 0;
232	int error = 0;
233	char buf[PATH_MAX];
234	
235	if (!errfunc) errfunc = ignore_err;
236
237	if (!(flags & GLOB_APPEND)) {
238		g->gl_offs = offs;
239		g->gl_pathc = 0;
240		g->gl_pathv = NULL;
241	}
242
243	if (*pat) {
244		char *p = strdup(pat);
245		if (!p) return GLOB_NOSPACE;
246		buf[0] = 0;
247		size_t pos = 0;
248		char *s = p;
249		if ((flags & (GLOB_TILDE | GLOB_TILDE_CHECK)) && *p == '~')
250			error = expand_tilde(&s, buf, &pos);
251		if (!error)
252			error = do_glob(buf, pos, 0, s, flags, errfunc, &tail);
253		free(p);
254	}
255
256	if (error == GLOB_NOSPACE) {
257		freelist(&head);
258		return error;
259	}
260	
261	for (cnt=0, tail=head.next; tail; tail=tail->next, cnt++);
262	if (!cnt) {
263		if (flags & GLOB_NOCHECK) {
264			tail = &head;
265			if (append(&tail, pat, strlen(pat), 0))
266				return GLOB_NOSPACE;
267			cnt++;
268		} else if (!error)
269			return GLOB_NOMATCH;
270	}
271
272	if (flags & GLOB_APPEND) {
273		char **pathv = realloc(g->gl_pathv, (offs + g->gl_pathc + cnt + 1) * sizeof(char *));
274		if (!pathv) {
275			freelist(&head);
276			return GLOB_NOSPACE;
277		}
278		g->gl_pathv = pathv;
279		offs += g->gl_pathc;
280	} else {
281		g->gl_pathv = malloc((offs + cnt + 1) * sizeof(char *));
282		if (!g->gl_pathv) {
283			freelist(&head);
284			return GLOB_NOSPACE;
285		}
286		for (i=0; i<offs; i++)
287			g->gl_pathv[i] = NULL;
288	}
289	for (i=0, tail=head.next; i<cnt; tail=tail->next, i++)
290		g->gl_pathv[offs + i] = tail->name;
291	g->gl_pathv[offs + i] = NULL;
292	g->gl_pathc += cnt;
293
294	if (!(flags & GLOB_NOSORT))
295		qsort(g->gl_pathv+offs, cnt, sizeof(char *), sort);
296	
297	return error;
298}
299
300void globfree(glob_t *g)
301{
302	size_t i;
303	for (i=0; i<g->gl_pathc; i++)
304		free(g->gl_pathv[g->gl_offs + i] - offsetof(struct match, name));
305	free(g->gl_pathv);
306	g->gl_pathc = 0;
307	g->gl_pathv = NULL;
308}