1/* exclude.c -- exclude file names
2
3   Copyright 1992, 1993, 1994, 1997, 1999, 2000, 2001 Free Software
4   Foundation, Inc.
5
6   This program is free software; you can redistribute it and/or modify
7   it under the terms of the GNU General Public License as published by
8   the Free Software Foundation; either version 2, or (at your option)
9   any later version.
10
11   This program is distributed in the hope that it will be useful,
12   but WITHOUT ANY WARRANTY; without even the implied warranty of
13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14   GNU General Public License for more details.
15
16   You should have received a copy of the GNU General Public License
17   along with this program; see the file COPYING.
18   If not, write to the Free Software Foundation,
19   59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
20
21/* Written by Paul Eggert <eggert@twinsun.com>  */
22
23#if HAVE_CONFIG_H
24# include <config.h>
25#endif
26
27#if HAVE_STDBOOL_H
28# include <stdbool.h>
29#else
30typedef enum {false = 0, true = 1} bool;
31#endif
32
33#include <errno.h>
34#ifndef errno
35extern int errno;
36#endif
37#include <stdio.h>
38#if HAVE_SYS_TYPES_H
39# include <sys/types.h>
40#endif
41#if HAVE_STDLIB_H
42# include <stdlib.h>
43#endif
44#if HAVE_STRING_H
45# include <string.h>
46#endif
47#if HAVE_STRINGS_H
48# include <strings.h>
49#endif
50#if HAVE_INTTYPES_H
51# include <inttypes.h>
52#else
53# if HAVE_STDINT_H
54#  include <stdint.h>
55# endif
56#endif
57
58#include "exclude.h"
59#include "fnmatch.h"
60#include "unlocked-io.h"
61#include "xalloc.h"
62
63#ifndef SIZE_MAX
64# define SIZE_MAX ((size_t) -1)
65#endif
66
67/* Verify a requirement at compile-time (unlike assert, which is runtime).  */
68#define verify(name, assertion) struct name { char a[(assertion) ? 1 : -1]; }
69
70verify (EXCLUDE_macros_do_not_collide_with_FNM_macros,
71	(((EXCLUDE_ANCHORED | EXCLUDE_INCLUDE | EXCLUDE_WILDCARDS)
72	  & (FNM_FILE_NAME | FNM_NOESCAPE | FNM_PERIOD | FNM_LEADING_DIR
73	     | FNM_CASEFOLD))
74	 == 0));
75
76/* An exclude pattern-options pair.  The options are fnmatch options
77   ORed with EXCLUDE_* options.  */
78
79struct patopts
80  {
81    char const *pattern;
82    int options;
83  };
84
85/* An exclude list, of pattern-options pairs.  */
86
87struct exclude
88  {
89    struct patopts *exclude;
90    size_t exclude_alloc;
91    size_t exclude_count;
92  };
93
94/* Return a newly allocated and empty exclude list.  */
95
96struct exclude *
97new_exclude (void)
98{
99  struct exclude *ex = (struct exclude *) xmalloc (sizeof *ex);
100  ex->exclude_count = 0;
101  ex->exclude_alloc = (1 << 6); /* This must be a power of 2.  */
102  ex->exclude = (struct patopts *) xmalloc (ex->exclude_alloc
103					    * sizeof ex->exclude[0]);
104  return ex;
105}
106
107/* Free the storage associated with an exclude list.  */
108
109void
110free_exclude (struct exclude *ex)
111{
112  free (ex->exclude);
113  free (ex);
114}
115
116/* Return zero if PATTERN matches F, obeying OPTIONS, except that
117   (unlike fnmatch) wildcards are disabled in PATTERN.  */
118
119static int
120fnmatch_no_wildcards (char const *pattern, char const *f, int options)
121{
122  if (! (options & FNM_LEADING_DIR))
123    return ((options & FNM_CASEFOLD)
124	    ? strcasecmp (pattern, f)
125	    : strcmp (pattern, f));
126  else
127    {
128      size_t patlen = strlen (pattern);
129      int r = ((options & FNM_CASEFOLD)
130		? strncasecmp (pattern, f, patlen)
131		: strncmp (pattern, f, patlen));
132      if (! r)
133	{
134	  r = f[patlen];
135	  if (r == '/')
136	    r = 0;
137	}
138      return r;
139    }
140}
141
142/* Return true if EX excludes F.  */
143
144bool
145excluded_filename (struct exclude const *ex, char const *f)
146{
147  size_t exclude_count = ex->exclude_count;
148
149  /* If no options are given, the default is to include.  */
150  if (exclude_count == 0)
151    return false;
152  else
153    {
154      struct patopts const *exclude = ex->exclude;
155      size_t i;
156
157      /* Otherwise, the default is the opposite of the first option.  */
158      bool excluded = !! (exclude[0].options & EXCLUDE_INCLUDE);
159
160      /* Scan through the options, seeing whether they change F from
161	 excluded to included or vice versa.  */
162      for (i = 0;  i < exclude_count;  i++)
163	{
164	  char const *pattern = exclude[i].pattern;
165	  int options = exclude[i].options;
166	  if (excluded == !! (options & EXCLUDE_INCLUDE))
167	    {
168	      int (*matcher) PARAMS ((char const *, char const *, int)) =
169		(options & EXCLUDE_WILDCARDS
170		 ? fnmatch
171		 : fnmatch_no_wildcards);
172	      bool matched = ((*matcher) (pattern, f, options) == 0);
173	      char const *p;
174
175	      if (! (options & EXCLUDE_ANCHORED))
176		for (p = f; *p && ! matched; p++)
177		  if (*p == '/' && p[1] != '/')
178		    matched = ((*matcher) (pattern, p + 1, options) == 0);
179
180	      excluded ^= matched;
181	    }
182	}
183
184      return excluded;
185    }
186}
187
188/* Append to EX the exclusion PATTERN with OPTIONS.  */
189
190void
191add_exclude (struct exclude *ex, char const *pattern, int options)
192{
193  struct patopts *patopts;
194
195  if (ex->exclude_alloc <= ex->exclude_count)
196    {
197      size_t s = 2 * ex->exclude_alloc;
198      if (! (0 < s && s <= SIZE_MAX / sizeof ex->exclude[0]))
199	xalloc_die ();
200      ex->exclude_alloc = s;
201      ex->exclude = (struct patopts *) xrealloc (ex->exclude,
202						 s * sizeof ex->exclude[0]);
203    }
204
205  patopts = &ex->exclude[ex->exclude_count++];
206  patopts->pattern = pattern;
207  patopts->options = options;
208}
209
210/* Use ADD_FUNC to append to EX the patterns in FILENAME, each with
211   OPTIONS.  LINE_END terminates each pattern in the file.  Return -1
212   on failure, 0 on success.  */
213
214int
215add_exclude_file (void (*add_func) PARAMS ((struct exclude *,
216					    char const *, int)),
217		  struct exclude *ex, char const *filename, int options,
218		  char line_end)
219{
220  bool use_stdin = filename[0] == '-' && !filename[1];
221  FILE *in;
222  char *buf;
223  char *p;
224  char const *pattern;
225  char const *lim;
226  size_t buf_alloc = (1 << 10);  /* This must be a power of two.  */
227  size_t buf_count = 0;
228  int c;
229  int e = 0;
230
231  if (use_stdin)
232    in = stdin;
233  else if (! (in = fopen (filename, "r")))
234    return -1;
235
236  buf = xmalloc (buf_alloc);
237
238  while ((c = getc (in)) != EOF)
239    {
240      buf[buf_count++] = c;
241      if (buf_count == buf_alloc)
242	{
243	  buf_alloc *= 2;
244	  if (! buf_alloc)
245	    xalloc_die ();
246	  buf = xrealloc (buf, buf_alloc);
247	}
248    }
249
250  if (ferror (in))
251    e = errno;
252
253  if (!use_stdin && fclose (in) != 0)
254    e = errno;
255
256  buf = xrealloc (buf, buf_count + 1);
257
258  for (pattern = p = buf, lim = buf + buf_count;  p <= lim;  p++)
259    if (p < lim ? *p == line_end : buf < p && p[-1])
260      {
261	*p = '\0';
262	(*add_func) (ex, pattern, options);
263	pattern = p + 1;
264      }
265
266  errno = e;
267  return e ? -1 : 0;
268}
269