1/* exclude.c -- exclude file names
2
3   Copyright (C) 1992, 1993, 1994, 1997, 1999, 2000, 2001, 2002, 2003 Free
4   Software 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#include <stdbool.h>
28
29#include <ctype.h>
30#include <errno.h>
31#ifndef errno
32extern int errno;
33#endif
34#include <stddef.h>
35#include <stdio.h>
36#include <stdlib.h>
37#include <string.h>
38
39#include "exclude.h"
40#include "fnmatch.h"
41#include "unlocked-io.h"
42#include "xalloc.h"
43
44#if STDC_HEADERS || (! defined isascii && ! HAVE_ISASCII)
45# define IN_CTYPE_DOMAIN(c) true
46#else
47# define IN_CTYPE_DOMAIN(c) isascii (c)
48#endif
49
50static inline bool
51is_space (unsigned char c)
52{
53  return IN_CTYPE_DOMAIN (c) && isspace (c);
54}
55
56/* Verify a requirement at compile-time (unlike assert, which is runtime).  */
57#define verify(name, assertion) struct name { char a[(assertion) ? 1 : -1]; }
58
59/* Non-GNU systems lack these options, so we don't need to check them.  */
60#ifndef FNM_CASEFOLD
61# define FNM_CASEFOLD 0
62#endif
63#ifndef FNM_LEADING_DIR
64# define FNM_LEADING_DIR 0
65#endif
66
67verify (EXCLUDE_macros_do_not_collide_with_FNM_macros,
68	(((EXCLUDE_ANCHORED | EXCLUDE_INCLUDE | EXCLUDE_WILDCARDS)
69	  & (FNM_PATHNAME | FNM_NOESCAPE | FNM_PERIOD | FNM_LEADING_DIR
70	     | FNM_CASEFOLD))
71	 == 0));
72
73/* An exclude pattern-options pair.  The options are fnmatch options
74   ORed with EXCLUDE_* options.  */
75
76struct patopts
77  {
78    char const *pattern;
79    int options;
80  };
81
82/* An exclude list, of pattern-options pairs.  */
83
84struct exclude
85  {
86    struct patopts *exclude;
87    size_t exclude_alloc;
88    size_t exclude_count;
89  };
90
91/* Return a newly allocated and empty exclude list.  */
92
93struct exclude *
94new_exclude (void)
95{
96  return xzalloc (sizeof *new_exclude ());
97}
98
99/* Free the storage associated with an exclude list.  */
100
101void
102free_exclude (struct exclude *ex)
103{
104  free (ex->exclude);
105  free (ex);
106}
107
108/* Return zero if PATTERN matches F, obeying OPTIONS, except that
109   (unlike fnmatch) wildcards are disabled in PATTERN.  */
110
111static int
112fnmatch_no_wildcards (char const *pattern, char const *f, int options)
113{
114  if (! (options & FNM_LEADING_DIR))
115    return ((options & FNM_CASEFOLD)
116	    ? strcasecmp (pattern, f)
117	    : strcmp (pattern, f));
118  else
119    {
120      size_t patlen = strlen (pattern);
121      int r = ((options & FNM_CASEFOLD)
122		? strncasecmp (pattern, f, patlen)
123		: strncmp (pattern, f, patlen));
124      if (! r)
125	{
126	  r = f[patlen];
127	  if (r == '/')
128	    r = 0;
129	}
130      return r;
131    }
132}
133
134/* Return true if EX excludes F.  */
135
136bool
137excluded_filename (struct exclude const *ex, char const *f)
138{
139  size_t exclude_count = ex->exclude_count;
140
141  /* If no options are given, the default is to include.  */
142  if (exclude_count == 0)
143    return false;
144  else
145    {
146      struct patopts const *exclude = ex->exclude;
147      size_t i;
148
149      /* Otherwise, the default is the opposite of the first option.  */
150      bool excluded = !! (exclude[0].options & EXCLUDE_INCLUDE);
151
152      /* Scan through the options, seeing whether they change F from
153	 excluded to included or vice versa.  */
154      for (i = 0;  i < exclude_count;  i++)
155	{
156	  char const *pattern = exclude[i].pattern;
157	  int options = exclude[i].options;
158	  if (excluded == !! (options & EXCLUDE_INCLUDE))
159	    {
160	      int (*matcher) (char const *, char const *, int) =
161		(options & EXCLUDE_WILDCARDS
162		 ? fnmatch
163		 : fnmatch_no_wildcards);
164	      bool matched = ((*matcher) (pattern, f, options) == 0);
165	      char const *p;
166
167	      if (! (options & EXCLUDE_ANCHORED))
168		for (p = f; *p && ! matched; p++)
169		  if (*p == '/' && p[1] != '/')
170		    matched = ((*matcher) (pattern, p + 1, options) == 0);
171
172	      excluded ^= matched;
173	    }
174	}
175
176      return excluded;
177    }
178}
179
180/* Append to EX the exclusion PATTERN with OPTIONS.  */
181
182void
183add_exclude (struct exclude *ex, char const *pattern, int options)
184{
185  struct patopts *patopts;
186
187  if (ex->exclude_count == ex->exclude_alloc)
188    ex->exclude = x2nrealloc (ex->exclude, &ex->exclude_alloc,
189			      sizeof *ex->exclude);
190
191  patopts = &ex->exclude[ex->exclude_count++];
192  patopts->pattern = pattern;
193  patopts->options = options;
194}
195
196/* Use ADD_FUNC to append to EX the patterns in FILENAME, each with
197   OPTIONS.  LINE_END terminates each pattern in the file.  If
198   LINE_END is a space character, ignore trailing spaces and empty
199   lines in FILE.  Return -1 on failure, 0 on success.  */
200
201int
202add_exclude_file (void (*add_func) (struct exclude *, char const *, int),
203		  struct exclude *ex, char const *filename, int options,
204		  char line_end)
205{
206  bool use_stdin = filename[0] == '-' && !filename[1];
207  FILE *in;
208  char *buf = NULL;
209  char *p;
210  char const *pattern;
211  char const *lim;
212  size_t buf_alloc = 0;
213  size_t buf_count = 0;
214  int c;
215  int e = 0;
216
217  if (use_stdin)
218    in = stdin;
219  else if (! (in = fopen (filename, "r")))
220    return -1;
221
222  while ((c = getc (in)) != EOF)
223    {
224      if (buf_count == buf_alloc)
225	buf = x2realloc (buf, &buf_alloc);
226      buf[buf_count++] = c;
227    }
228
229  if (ferror (in))
230    e = errno;
231
232  if (!use_stdin && fclose (in) != 0)
233    e = errno;
234
235  buf = xrealloc (buf, buf_count + 1);
236  buf[buf_count] = line_end;
237  lim = buf + buf_count + ! (buf_count == 0 || buf[buf_count - 1] == line_end);
238  pattern = buf;
239
240  for (p = buf; p < lim; p++)
241    if (*p == line_end)
242      {
243	char *pattern_end = p;
244
245	if (is_space (line_end))
246	  {
247	    for (; ; pattern_end--)
248	      if (pattern_end == pattern)
249		goto next_pattern;
250	      else if (! is_space (pattern_end[-1]))
251		break;
252	  }
253
254	*pattern_end = '\0';
255	(*add_func) (ex, pattern, options);
256
257      next_pattern:
258	pattern = p + 1;
259      }
260
261  errno = e;
262  return e ? -1 : 0;
263}
264