1/* Utility functions for finding files relative to GCC binaries.
2   Copyright (C) 1992-2015 Free Software Foundation, Inc.
3
4This file is part of GCC.
5
6GCC is free software; you can redistribute it and/or modify it under
7the terms of the GNU General Public License as published by the Free
8Software Foundation; either version 3, or (at your option) any later
9version.
10
11GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12WARRANTY; without even the implied warranty of MERCHANTABILITY or
13FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14for more details.
15
16You should have received a copy of the GNU General Public License
17along with GCC; see the file COPYING3.  If not see
18<http://www.gnu.org/licenses/>.  */
19
20#include "config.h"
21#include "system.h"
22#include "filenames.h"
23#include "file-find.h"
24
25static bool debug = false;
26
27void
28find_file_set_debug (bool debug_state)
29{
30  debug = debug_state;
31}
32
33char *
34find_a_file (struct path_prefix *pprefix, const char *name, int mode)
35{
36  char *temp;
37  struct prefix_list *pl;
38  int len = pprefix->max_len + strlen (name) + 1;
39
40  if (debug)
41    fprintf (stderr, "Looking for '%s'\n", name);
42
43#ifdef HOST_EXECUTABLE_SUFFIX
44  len += strlen (HOST_EXECUTABLE_SUFFIX);
45#endif
46
47  temp = XNEWVEC (char, len);
48
49  /* Determine the filename to execute (special case for absolute paths).  */
50
51  if (IS_ABSOLUTE_PATH (name))
52    {
53      if (access (name, mode) == 0)
54	{
55	  strcpy (temp, name);
56
57	  if (debug)
58	    fprintf (stderr, "  - found: absolute path\n");
59
60	  return temp;
61	}
62
63#ifdef HOST_EXECUTABLE_SUFFIX
64	/* Some systems have a suffix for executable files.
65	   So try appending that.  */
66      strcpy (temp, name);
67	strcat (temp, HOST_EXECUTABLE_SUFFIX);
68
69	if (access (temp, mode) == 0)
70	  return temp;
71#endif
72
73      if (debug)
74	fprintf (stderr, "  - failed to locate using absolute path\n");
75    }
76  else
77    for (pl = pprefix->plist; pl; pl = pl->next)
78      {
79	struct stat st;
80
81	strcpy (temp, pl->prefix);
82	strcat (temp, name);
83
84	if (stat (temp, &st) >= 0
85	    && ! S_ISDIR (st.st_mode)
86	    && access (temp, mode) == 0)
87	  return temp;
88
89#ifdef HOST_EXECUTABLE_SUFFIX
90	/* Some systems have a suffix for executable files.
91	   So try appending that.  */
92	strcat (temp, HOST_EXECUTABLE_SUFFIX);
93
94	if (stat (temp, &st) >= 0
95	    && ! S_ISDIR (st.st_mode)
96	    && access (temp, mode) == 0)
97	  return temp;
98#endif
99      }
100
101  if (debug && pprefix->plist == NULL)
102    fprintf (stderr, "  - failed: no entries in prefix list\n");
103
104  free (temp);
105  return 0;
106}
107
108/* Add an entry for PREFIX to prefix list PREFIX.
109   Add at beginning if FIRST is true.  */
110
111void
112do_add_prefix (struct path_prefix *pprefix, const char *prefix, bool first)
113{
114  struct prefix_list *pl, **prev;
115  int len;
116
117  if (pprefix->plist && !first)
118    {
119      for (pl = pprefix->plist; pl->next; pl = pl->next)
120	;
121      prev = &pl->next;
122    }
123  else
124    prev = &pprefix->plist;
125
126  /* Keep track of the longest prefix.  */
127
128  len = strlen (prefix);
129  if (len > pprefix->max_len)
130    pprefix->max_len = len;
131
132  pl = XNEW (struct prefix_list);
133  pl->prefix = xstrdup (prefix);
134
135  if (*prev)
136    pl->next = *prev;
137  else
138    pl->next = (struct prefix_list *) 0;
139  *prev = pl;
140}
141
142/* Add an entry for PREFIX at the end of prefix list PREFIX.  */
143
144void
145add_prefix (struct path_prefix *pprefix, const char *prefix)
146{
147  do_add_prefix (pprefix, prefix, false);
148}
149
150/* Add an entry for PREFIX at the begin of prefix list PREFIX.  */
151
152void
153add_prefix_begin (struct path_prefix *pprefix, const char *prefix)
154{
155  do_add_prefix (pprefix, prefix, true);
156}
157
158/* Take the value of the environment variable ENV, break it into a path, and
159   add of the entries to PPREFIX.  */
160
161void
162prefix_from_env (const char *env, struct path_prefix *pprefix)
163{
164  const char *p;
165  p = getenv (env);
166
167  if (p)
168    prefix_from_string (p, pprefix);
169}
170
171void
172prefix_from_string (const char *p, struct path_prefix *pprefix)
173{
174  const char *startp, *endp;
175  char *nstore = XNEWVEC (char, strlen (p) + 3);
176
177  if (debug)
178    fprintf (stderr, "Convert string '%s' into prefixes, separator = '%c'\n", p, PATH_SEPARATOR);
179
180  startp = endp = p;
181  while (1)
182    {
183      if (*endp == PATH_SEPARATOR || *endp == 0)
184	{
185	  strncpy (nstore, startp, endp-startp);
186	  if (endp == startp)
187	    {
188	      strcpy (nstore, "./");
189	    }
190	  else if (! IS_DIR_SEPARATOR (endp[-1]))
191	    {
192	      nstore[endp-startp] = DIR_SEPARATOR;
193	      nstore[endp-startp+1] = 0;
194	    }
195	  else
196	    nstore[endp-startp] = 0;
197
198	  if (debug)
199	    fprintf (stderr, "  - add prefix: %s\n", nstore);
200
201	  add_prefix (pprefix, nstore);
202	  if (*endp == 0)
203	    break;
204	  endp = startp = endp + 1;
205	}
206      else
207	endp++;
208    }
209  free (nstore);
210}
211