summaryrefslogtreecommitdiff
path: root/Build/source/texk/kpathsea/cnf.c
blob: 60a5df93e6de98d27d9eb1294fb3924ff7206f97 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
/* cnf.c: read config files.

   Copyright 1994, 1995, 1996, 1997, 2008, 2009, 2011, 2012, 2016,
   2017, 2018 Karl Berry.
   Copyright 1997-2005 Olaf Weber.

   This library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   This library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public License
   along with this library; if not, see <http://www.gnu.org/licenses/>.  */

#include <kpathsea/config.h>
#include <kpathsea/c-fopen.h>
#include <kpathsea/c-ctype.h>
#include <kpathsea/c-pathch.h>
#include <kpathsea/cnf.h>
#include <kpathsea/db.h>
#include <kpathsea/hash.h>
#include <kpathsea/line.h>
#include <kpathsea/paths.h>
#include <kpathsea/pathsearch.h>
#include <kpathsea/tex-file.h>
#include <kpathsea/variable.h>

/* By using our own hash table, instead of the environment, we
   complicate variable expansion (because we have to look in two
   places), but we don't bang so much on the system.  DOS and System V
   have very limited environment space.  Also, this way
   `kpse_init_format' can distinguish between values originating from
   the cnf file and ones from environment variables, which can be useful
   for users trying to figure out what's going on.  */

#define CNF_HASH_SIZE 751
#define CNF_NAME "texmf.cnf"


/* Do a single line in a cnf file: if it's blank or a comment or
   erroneous, skip it.  Otherwise, parse
     <variable>[.<program>] [=] <value>
   Do this even if the <variable> is already set in the environment,
   since the envvalue might contain a trailing :, in which case we'll be
   looking for the cnf value.
   
   We return NULL if ok, an error string otherwise.  */

static string
do_line (kpathsea kpse, string line)
{
  unsigned len;
  string start;
  string value, var;
  string prog = NULL;

  /* Skip leading whitespace.  */
  while (*line && ISSPACE (*line))
    line++;

  /* More to do only if we have non-comment material left.  */
  if (*line == 0 || *line == '%' || *line == '#')
    return NULL;

  /* Remove trailing comment: a % or # preceded by whitespace.  Also
     remove any whitespace before that.  For example, the value for
       foo = a#b  %something
     is a#b.  */
  value = line + strlen (line) - 1; /* start at end of line */
  while (value > line) {            
    if (*value == '%' || *value == '#') {
      value--;                      /* move before comment char */
      while (ISSPACE (*value))
        *value-- = 0;               /* wipe out as much preceding whitespace
      continue;                        (and comment) as we find */
    }
    value--;                        /* move before the new null byte */
  }

  /* The variable name is everything up to the next space or = or `.'.  */
  start = line;
  while (*line && !ISSPACE (*line) && *line != '=' && *line != '.')
    line++;

  /* `line' is now one character past the end of the variable name.  */
  len = line - start;
  if (len == 0) {
    return ("No cnf variable name");
  }
  
  var = (string) xmalloc (len + 1);
  strncpy (var, start, len);
  var[len] = 0;

  /* If the variable is qualified with a program name, find out which. */
  while (*line && ISSPACE (*line))
    line++;
  if (*line == '.') {
    /* Skip spaces, then everything up to the next space or =.  */
    line++;
    while (ISSPACE (*line))
      line++;
    start = line;
    while (*line && !ISSPACE (*line) && *line != '=')
      line++;

    /* It's annoying to repeat all this, but making a tokenizing
       subroutine would be just as long and annoying.  */
    len = line - start;
    prog = (string) xmalloc (len + 1);
    strncpy (prog, start, len);
    prog[len] = 0;
  }

  /* Skip whitespace, an optional =, more whitespace.  */
  while (*line && ISSPACE (*line))
    line++;
  if (*line == '=') {
    line++;
    while (*line && ISSPACE (*line))
      line++;
  }

  /* The value is whatever remains.  Remove trailing whitespace.  */
  start = line;
  len = strlen (start);
  while (len > 0 && ISSPACE (start[len - 1]))
    len--;
  if (len == 0) {
    return ("No cnf value");
  }
  
  value = (string) xmalloc (len + 1);
  strncpy (value, start, len);
  value[len] = 0;

  /* Suppose we want to write a single texmf.cnf that can be used under
     both Windows and Unix. This is feasible except for the path
     separators: : on Unix, ; on Windows. We can't switch Windows to
     allowing :, since : is the drive separator. So we switch Unix to
     allowing ;. On the other hand, we don't want to change IS_ENV_SEP
     and all the rest.

     So, translate all ;'s in the path values to :'s if we'd normally
     use :. (Fortunately we don't use ; as a normal character in values.)  */

  if (IS_ENV_SEP(':')) {
      string loc;
      for (loc = value; *loc; loc++) {
          if (*loc == ';')
              *loc = ':';
      }
  }

  /* We want TEXINPUTS.prog to override plain TEXINPUTS.  The simplest
     way is to put both in the hash table (so we don't have to write
     hash_delete and hash_replace, and keep track of values' sources),
     and then look up the .prog version first in `kpse_cnf_get'.  */
  if (prog) {
    string lhs = concat3 (var, ".", prog);
    free (var);
    free (prog);
    var = lhs;
  }
  /* last-ditch debug */
  /* fprintf (stderr, "kpse/cnf.c hash_insert(%s,%s)\n", var, value); */
  hash_insert (&(kpse->cnf_hash), var, value);

  /* We should check that anything remaining is preceded by a comment
     character, but we don't.  Sorry.  */
  return NULL;
}

/* Read all the configuration files in the path.  */

static void
read_all_cnf (kpathsea kpse)
{
  string *cnf_files;
  string *cnf;
  const_string cnf_path = kpathsea_init_format (kpse, kpse_cnf_format);

  kpse->cnf_hash = hash_create (CNF_HASH_SIZE);

  cnf_files = kpathsea_all_path_search (kpse, cnf_path, CNF_NAME);
  if (cnf_files && *cnf_files) {
    for (cnf = cnf_files; *cnf; cnf++) {
      string line;
      string msg;
      unsigned lineno = 0;
      FILE *cnf_file = xfopen (*cnf, FOPEN_R_MODE);
      if (kpse->record_input)
        kpse->record_input (*cnf);

      while ((line = read_line (cnf_file)) != NULL) {
        unsigned len;
        lineno++;
        len = strlen (line);
        /* Strip trailing spaces. */
        while (len > 0 && ISSPACE(line[len-1])) {
          line[len - 1] = 0;
          --len;
        }
        /* Concatenate consecutive lines that end with \.  */
        while (len > 0 && line[len - 1] == '\\') {
          string next_line = read_line (cnf_file);
          lineno++;
          line[len - 1] = 0;
          if (!next_line) {
            WARNING2 ("%s:%d: (kpathsea) Last line of file ends with \\",
                       *cnf, lineno);
          } else {
            string new_line;
            new_line = concat (line, next_line);
            free (line);
            line = new_line;
            len = strlen (line);
          }
        }

        msg = do_line (kpse, line);
        if (msg) {
          WARNING4 ("%s:%d: (kpathsea) %s on line: %s",
                    *cnf, lineno, msg, line);
        }
        free (line);
      }

      xfclose (cnf_file, *cnf);
      free (*cnf);
    }
    free (cnf_files);
  } else {
    string warn = getenv ("KPATHSEA_WARNING");
    if (!(warn && STREQ (warn, "0"))) {
      WARNING1
  ("kpathsea: configuration file texmf.cnf not found in these directories: %s",
        cnf_path);
    }
  }
}

/* Read the cnf files on the first call.  Return the first value in the
   returned list -- this will be from the last-read cnf file.  */

const_string
kpathsea_cnf_get (kpathsea kpse, const_string name)
{
  string ctry;
  const_string ret, *ret_list;

  /* When we expand the compile-time value for DEFAULT_TEXMFCNF,
     we end up needing the value for TETEXDIR and other variables,
     so kpse_var_expand ends up calling us again.  No good.  Except this
     code is not sufficient, somehow the ls-R path needs to be
     computed when initializing the cnf path.  Better to ensure that the
     compile-time path does not contain variable references.  */
  if (kpse->doing_cnf_init)
    return NULL;

  if (kpse->cnf_hash.size == 0) {
    /* Read configuration files and initialize databases.  */
    kpse->doing_cnf_init = true;
    read_all_cnf (kpse);
    kpse->doing_cnf_init = false;

    /* Since `kpse_init_db' recursively calls us, we must call it from
       outside a `kpse_path_element' loop (namely, the one in
       `read_all_cnf' above): `kpse_path_element' is not reentrant.  */
    kpathsea_init_db (kpse);
  }

  /* First look up NAME.`kpse->program_name', then NAME.  */
  assert (kpse->program_name);
  ctry = concat3 (name, ".", kpse->program_name);
  ret_list = hash_lookup (kpse->cnf_hash, ctry);
  free (ctry);
  if (ret_list) {
    ret = *ret_list;
    free (ret_list);
  } else {
    ret_list = hash_lookup (kpse->cnf_hash, name);
    if (ret_list) {
      ret = *ret_list;
      free (ret_list);
    } else {
      ret = NULL;
    }
  }

  return ret;
}

#if defined(KPSE_COMPAT_API)
const_string
kpse_cnf_get (const_string name)
{
    return kpathsea_cnf_get(kpse_def, name);
}
#endif