xref: /netbsd-src/external/gpl2/diffutils/dist/lib/exclude.c (revision 75f6d617e282811cb173c2ccfbf5df0dd71f7045)
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
32 typedef enum {false = 0, true = 1} bool;
33 #endif
34 
35 #include <errno.h>
36 #ifndef errno
37 extern 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 
72 verify (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 
81 struct patopts
82   {
83     char const *pattern;
84     int options;
85   };
86 
87 /* An exclude list, of pattern-options pairs.  */
88 
89 struct 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 
98 struct exclude *
new_exclude(void)99 new_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 
111 void
free_exclude(struct exclude * ex)112 free_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 
121 static int
fnmatch_no_wildcards(char const * pattern,char const * f,int options)122 fnmatch_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 
146 bool
excluded_filename(struct exclude const * ex,char const * f)147 excluded_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 
192 void
add_exclude(struct exclude * ex,char const * pattern,int options)193 add_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 
216 int
add_exclude_file(void (* add_func)PARAMS ((struct exclude *,char const *,int)),struct exclude * ex,char const * filename,int options,char line_end)217 add_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