1/*	$NetBSD: exclude.c,v 1.1.1.1 2016/01/13 03:15:30 christos Exp $	*/
2
3/* exclude.c -- exclude file names
4
5   Copyright 1992, 1993, 1994, 1997, 1999, 2000, 2001 Free Software
6   Foundation, Inc.
7
8   This program is free software; you can redistribute it and/or modify
9   it under the terms of the GNU General Public License as published by
10   the Free Software Foundation; either version 2, or (at your option)
11   any later version.
12
13   This program is distributed in the hope that it will be useful,
14   but WITHOUT ANY WARRANTY; without even the implied warranty of
15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16   GNU General Public License for more details.
17
18   You should have received a copy of the GNU General Public License
19   along with this program; see the file COPYING.
20   If not, write to the Free Software Foundation,
21   59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
22
23/* Written by Paul Eggert <eggert@twinsun.com>  */
24
25#if HAVE_CONFIG_H
26# include <config.h>
27#endif
28
29#if HAVE_STDBOOL_H
30# include <stdbool.h>
31#else
32typedef enum {false = 0, true = 1} bool;
33#endif
34
35#include <errno.h>
36#ifndef errno
37extern int errno;
38#endif
39#include <stdio.h>
40#if HAVE_SYS_TYPES_H
41# include <sys/types.h>
42#endif
43#if HAVE_STDLIB_H
44# include <stdlib.h>
45#endif
46#if HAVE_STRING_H
47# include <string.h>
48#endif
49#if HAVE_STRINGS_H
50# include <strings.h>
51#endif
52#if HAVE_INTTYPES_H
53# include <inttypes.h>
54#else
55# if HAVE_STDINT_H
56#  include <stdint.h>
57# endif
58#endif
59
60#include "exclude.h"
61#include "fnmatch.h"
62#include "unlocked-io.h"
63#include "xalloc.h"
64
65#ifndef SIZE_MAX
66# define SIZE_MAX ((size_t) -1)
67#endif
68
69/* Verify a requirement at compile-time (unlike assert, which is runtime).  */
70#define verify(name, assertion) struct name { char a[(assertion) ? 1 : -1]; }
71
72verify (EXCLUDE_macros_do_not_collide_with_FNM_macros,
73	(((EXCLUDE_ANCHORED | EXCLUDE_INCLUDE | EXCLUDE_WILDCARDS)
74	  & (FNM_FILE_NAME | FNM_NOESCAPE | FNM_PERIOD | FNM_LEADING_DIR
75	     | FNM_CASEFOLD))
76	 == 0));
77
78/* An exclude pattern-options pair.  The options are fnmatch options
79   ORed with EXCLUDE_* options.  */
80
81struct patopts
82  {
83    char const *pattern;
84    int options;
85  };
86
87/* An exclude list, of pattern-options pairs.  */
88
89struct exclude
90  {
91    struct patopts *exclude;
92    size_t exclude_alloc;
93    size_t exclude_count;
94  };
95
96/* Return a newly allocated and empty exclude list.  */
97
98struct exclude *
99new_exclude (void)
100{
101  struct exclude *ex = (struct exclude *) xmalloc (sizeof *ex);
102  ex->exclude_count = 0;
103  ex->exclude_alloc = (1 << 6); /* This must be a power of 2.  */
104  ex->exclude = (struct patopts *) xmalloc (ex->exclude_alloc
105					    * sizeof ex->exclude[0]);
106  return ex;
107}
108
109/* Free the storage associated with an exclude list.  */
110
111void
112free_exclude (struct exclude *ex)
113{
114  free (ex->exclude);
115  free (ex);
116}
117
118/* Return zero if PATTERN matches F, obeying OPTIONS, except that
119   (unlike fnmatch) wildcards are disabled in PATTERN.  */
120
121static int
122fnmatch_no_wildcards (char const *pattern, char const *f, int options)
123{
124  if (! (options & FNM_LEADING_DIR))
125    return ((options & FNM_CASEFOLD)
126	    ? strcasecmp (pattern, f)
127	    : strcmp (pattern, f));
128  else
129    {
130      size_t patlen = strlen (pattern);
131      int r = ((options & FNM_CASEFOLD)
132		? strncasecmp (pattern, f, patlen)
133		: strncmp (pattern, f, patlen));
134      if (! r)
135	{
136	  r = f[patlen];
137	  if (r == '/')
138	    r = 0;
139	}
140      return r;
141    }
142}
143
144/* Return true if EX excludes F.  */
145
146bool
147excluded_filename (struct exclude const *ex, char const *f)
148{
149  size_t exclude_count = ex->exclude_count;
150
151  /* If no options are given, the default is to include.  */
152  if (exclude_count == 0)
153    return false;
154  else
155    {
156      struct patopts const *exclude = ex->exclude;
157      size_t i;
158
159      /* Otherwise, the default is the opposite of the first option.  */
160      bool excluded = !! (exclude[0].options & EXCLUDE_INCLUDE);
161
162      /* Scan through the options, seeing whether they change F from
163	 excluded to included or vice versa.  */
164      for (i = 0;  i < exclude_count;  i++)
165	{
166	  char const *pattern = exclude[i].pattern;
167	  int options = exclude[i].options;
168	  if (excluded == !! (options & EXCLUDE_INCLUDE))
169	    {
170	      int (*matcher) PARAMS ((char const *, char const *, int)) =
171		(options & EXCLUDE_WILDCARDS
172		 ? fnmatch
173		 : fnmatch_no_wildcards);
174	      bool matched = ((*matcher) (pattern, f, options) == 0);
175	      char const *p;
176
177	      if (! (options & EXCLUDE_ANCHORED))
178		for (p = f; *p && ! matched; p++)
179		  if (*p == '/' && p[1] != '/')
180		    matched = ((*matcher) (pattern, p + 1, options) == 0);
181
182	      excluded ^= matched;
183	    }
184	}
185
186      return excluded;
187    }
188}
189
190/* Append to EX the exclusion PATTERN with OPTIONS.  */
191
192void
193add_exclude (struct exclude *ex, char const *pattern, int options)
194{
195  struct patopts *patopts;
196
197  if (ex->exclude_alloc <= ex->exclude_count)
198    {
199      size_t s = 2 * ex->exclude_alloc;
200      if (! (0 < s && s <= SIZE_MAX / sizeof ex->exclude[0]))
201	xalloc_die ();
202      ex->exclude_alloc = s;
203      ex->exclude = (struct patopts *) xrealloc (ex->exclude,
204						 s * sizeof ex->exclude[0]);
205    }
206
207  patopts = &ex->exclude[ex->exclude_count++];
208  patopts->pattern = pattern;
209  patopts->options = options;
210}
211
212/* Use ADD_FUNC to append to EX the patterns in FILENAME, each with
213   OPTIONS.  LINE_END terminates each pattern in the file.  Return -1
214   on failure, 0 on success.  */
215
216int
217add_exclude_file (void (*add_func) PARAMS ((struct exclude *,
218					    char const *, int)),
219		  struct exclude *ex, char const *filename, int options,
220		  char line_end)
221{
222  bool use_stdin = filename[0] == '-' && !filename[1];
223  FILE *in;
224  char *buf;
225  char *p;
226  char const *pattern;
227  char const *lim;
228  size_t buf_alloc = (1 << 10);  /* This must be a power of two.  */
229  size_t buf_count = 0;
230  int c;
231  int e = 0;
232
233  if (use_stdin)
234    in = stdin;
235  else if (! (in = fopen (filename, "r")))
236    return -1;
237
238  buf = xmalloc (buf_alloc);
239
240  while ((c = getc (in)) != EOF)
241    {
242      buf[buf_count++] = c;
243      if (buf_count == buf_alloc)
244	{
245	  buf_alloc *= 2;
246	  if (! buf_alloc)
247	    xalloc_die ();
248	  buf = xrealloc (buf, buf_alloc);
249	}
250    }
251
252  if (ferror (in))
253    e = errno;
254
255  if (!use_stdin && fclose (in) != 0)
256    e = errno;
257
258  buf = xrealloc (buf, buf_count + 1);
259
260  for (pattern = p = buf, lim = buf + buf_count;  p <= lim;  p++)
261    if (p < lim ? *p == line_end : buf < p && p[-1])
262      {
263	*p = '\0';
264	(*add_func) (ex, pattern, options);
265	pattern = p + 1;
266      }
267
268  errno = e;
269  return e ? -1 : 0;
270}
271