summary refs log tree commit diff
path: root/elf/cache.c
blob: d95f93cf916130a4b11ffd51c206a65a77fd302f (plain) (blame)
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
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
/* Copyright (C) 1999, 2000, 2001 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Andreas Jaeger <aj@suse.de>, 1999.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public License as
   published by the Free Software Foundation; either version 2 of the
   License, or (at your option) any later version.

   The GNU C 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
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with the GNU C Library; see the file COPYING.LIB.  If not,
   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#include <errno.h>
#include <error.h>
#include <dirent.h>
#include <inttypes.h>
#include <libintl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/fcntl.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/types.h>

#include "ldconfig.h"
#include "dl-cache.h"

struct cache_entry
{
  char *lib;			/* Library name.  */
  char *path;			/* Path to find library.  */
  int flags;			/* Flags to indicate kind of library.  */
  unsigned int osversion;	/* Required OS version.  */
  uint64_t hwcap;		/* Important hardware capabilities.  */
  int bits_hwcap;		/* Number of bits set in hwcap.  */
  struct cache_entry *next;	/* Next entry in list.  */
};

/* List of all cache entries.  */
static struct cache_entry *entries;

static const char *flag_descr[] =
{ "libc4", "ELF", "libc5", "libc6"};

/* Print a single entry.  */
static void
print_entry (const char *lib, int flag, unsigned int osversion,
	     uint64_t hwcap, const char *key)
{
  printf ("\t%s (", lib);
  switch (flag & FLAG_TYPE_MASK)
    {
    case FLAG_LIBC4:
    case FLAG_ELF:
    case FLAG_ELF_LIBC5:
    case FLAG_ELF_LIBC6:
      fputs (flag_descr[flag & FLAG_TYPE_MASK], stdout);
      break;
    default:
      fputs (_("unknown"), stdout);
      break;
    }
  switch (flag & FLAG_REQUIRED_MASK)
    {
#ifdef __sparc__
    case FLAG_SPARC_LIB64:
      fputs (",64bit", stdout);
#endif
#if defined __ia64__ || defined __i386__
    case FLAG_IA64_LIB64:
      fputs (",IA-64", stdout);
#endif
#if defined __s390__ || defined __s390x__
    case FLAG_S390_LIB64:
      fputs(",64bit", stdout);
#endif
    case 0:
      break;
    default:
      printf (",%d", flag & FLAG_REQUIRED_MASK);
      break;
    }
  if (hwcap != 0)
    printf (", hwcap: 0x%" PRIx64, hwcap);
  if (osversion != 0)
    {
      static const char *const abi_tag_os[] =
      {
	[0] = "Linux",
	[1] = "Hurd",
	[2] = "Solaris",
	[3] = N_("Unknown OS")
      };
      unsigned int os = osversion >> 24;

      printf (_(", OS ABI: %s %d.%d.%d"),
	      _(abi_tag_os[os > 3 ? 3 : os]),
	      (osversion >> 16) & 0xff,
	      (osversion >> 8) & 0xff,
	      osversion & 0xff);
    }
  printf (") => %s\n", key);
}


/* Print the whole cache file, if a file contains the new cache format
   hidden in the old one, print the contents of the new format.  */
void
print_cache (const char *cache_name)
{
  size_t cache_size;
  struct stat64 st;
  int fd;
  unsigned int i;
  struct cache_file *cache;
  struct cache_file_new *cache_new = NULL;
  const char *cache_data;
  int format = 0;

  fd = open (cache_name, O_RDONLY);
  if (fd < 0)
    error (EXIT_FAILURE, errno, _("Can't open cache file %s\n"), cache_name);

  if (fstat64 (fd, &st) < 0
      /* No need to map the file if it is empty.  */
      || st.st_size == 0)
    {
      close (fd);
      return;
    }

  cache = mmap (0, st.st_size, PROT_READ, MAP_SHARED, fd, 0);
  if (cache == MAP_FAILED)
    error (EXIT_FAILURE, errno, _("mmap of cache file failed.\n"));
  cache_size = st.st_size;

  if (cache_size < sizeof (struct cache_file))
    error (EXIT_FAILURE, 0, _("File is not a cache file.\n"));

  if (memcmp (cache->magic, CACHEMAGIC, sizeof CACHEMAGIC - 1))
    {
      /* This can only be the new format without the old one.  */
      cache_new = (struct cache_file_new *) cache;

      if (memcmp (cache_new->magic, CACHEMAGIC_NEW, sizeof CACHEMAGIC_NEW - 1)
	  || memcmp (cache_new->version, CACHE_VERSION,
		      sizeof CACHE_VERSION - 1))
	error (EXIT_FAILURE, 0, _("File is not a cache file.\n"));
      format = 1;
      /* This is where the strings start.  */
      cache_data = (const char *) cache_new;
    }
  else
    {
      size_t offset = ALIGN_CACHE (sizeof (struct cache_file)
				   + (cache->nlibs
				      * sizeof (struct file_entry)));
      /* This is where the strings start.  */
      cache_data = (const char *) &cache->libs[cache->nlibs];

      /* Check for a new cache embedded in the old format.  */
      if (cache_size >
	  (offset + sizeof (struct cache_file_new)))
	{

	  cache_new = (struct cache_file_new *) ((void *)cache + offset);

	  if (memcmp (cache_new->magic, CACHEMAGIC_NEW,
		      sizeof CACHEMAGIC_NEW - 1) == 0
	      && memcmp (cache_new->version, CACHE_VERSION,
			 sizeof CACHE_VERSION - 1) == 0)
	    {
	      cache_data = (const char *) cache_new;
	      format = 1;
	    }
	}
    }

  if (format == 0)
    {
      printf (_("%d libs found in cache `%s'\n"), cache->nlibs, cache_name);

      /* Print everything.  */
      for (i = 0; i < cache->nlibs; i++)
	print_entry (cache_data + cache->libs[i].key,
		     cache->libs[i].flags, 0, 0,
		     cache_data + cache->libs[i].value);
    }
  else if (format == 1)
    {
      printf (_("%d libs found in cache `%s'\n"),
	      cache_new->nlibs, cache_name);

      /* Print everything.  */
      for (i = 0; i < cache_new->nlibs; i++)
	print_entry (cache_data + cache_new->libs[i].key,
		     cache_new->libs[i].flags,
		     cache_new->libs[i].osversion,
		     cache_new->libs[i].hwcap,
		     cache_data + cache_new->libs[i].value);
    }
  /* Cleanup.  */
  munmap (cache, cache_size);
  close (fd);
}

/* Initialize cache data structures.  */
void
init_cache (void)
{
  entries = NULL;
}



static
int compare (const struct cache_entry *e1, const struct cache_entry *e2)
{
  int res;

  /* We need to swap entries here to get the correct sort order.  */
  res = _dl_cache_libcmp (e2->lib, e1->lib);
  if (res == 0)
    {
      if (e1->flags < e2->flags)
	return 1;
      else if (e1->flags > e2->flags)
	return -1;
      /* Sort by most specific hwcap.  */
      else if (e2->bits_hwcap > e1->bits_hwcap)
	return 1;
      else if (e2->bits_hwcap < e1->bits_hwcap)
	return -1;
      else if (e2->hwcap > e1->hwcap)
	return 1;
      else if (e2->hwcap < e1->hwcap)
	return -1;
      if (e2->osversion > e1->osversion)
	return 1;
      if (e2->osversion < e1->osversion)
	return -1;
    }
  return res;
}

/* Save the contents of the cache.  */
void
save_cache (const char *cache_name)
{
  struct cache_entry *entry;
  int fd, idx_old, idx_new;
  size_t total_strlen, len;
  char *strings, *str, *temp_name;
  struct cache_file *file_entries = NULL;
  struct cache_file_new *file_entries_new = NULL;
  size_t file_entries_size = 0;
  size_t file_entries_new_size = 0;
  unsigned int str_offset;
  /* Number of cache entries.  */
  int cache_entry_count = 0;
  /* Number of normal cache entries.  */
  int cache_entry_old_count = 0;
  /* Pad for alignment of cache_file_new.  */
  size_t pad;

  /* The cache entries are sorted already, save them in this order. */

  /* Count the length of all strings.  */
  /* The old format doesn't contain hwcap entries and doesn't contain
     libraries in subdirectories with hwcaps entries.  Count therefore
     also all entries with hwcap == 0.  */
  total_strlen = 0;
  for (entry = entries; entry != NULL; entry = entry->next)
    {
      /* Account the final NULs.  */
      total_strlen += strlen (entry->lib) + strlen (entry->path) + 2;
      ++cache_entry_count;
      if (entry->hwcap == 0)
	++cache_entry_old_count;
    }

  /* Create the on disk cache structure.  */
  /* First an array for all strings.  */
  strings = (char *)xmalloc (total_strlen);

  if (opt_format != 2)
    {
      /* And the list of all entries in the old format.  */
      file_entries_size = sizeof (struct cache_file)
	+ cache_entry_old_count * sizeof (struct file_entry);
      file_entries = (struct cache_file *) xmalloc (file_entries_size);

      /* Fill in the header.  */
      memset (file_entries, 0, sizeof (struct cache_file));
      memcpy (file_entries->magic, CACHEMAGIC, sizeof CACHEMAGIC - 1);

      file_entries->nlibs = cache_entry_old_count;
    }

  if (opt_format != 0)
    {
      /* And the list of all entries in the new format.  */
      file_entries_new_size = sizeof (struct cache_file_new)
	+ cache_entry_count * sizeof (struct file_entry_new);
      file_entries_new =
	(struct cache_file_new *) xmalloc (file_entries_new_size);

      /* Fill in the header.  */
      memset (file_entries_new, 0, sizeof (struct cache_file_new));
      memcpy (file_entries_new->magic, CACHEMAGIC_NEW,
	      sizeof CACHEMAGIC_NEW - 1);
      memcpy (file_entries_new->version, CACHE_VERSION,
	      sizeof CACHE_VERSION - 1);

      file_entries_new->nlibs = cache_entry_count;
      file_entries_new->len_strings = total_strlen;
    }

  pad = ALIGN_CACHE (file_entries_size) - file_entries_size;

  /* If we have both formats, we hide the new format in the strings
     table, we have to adjust all string indices for this so that
     old libc5/glibc 2 dynamic linkers just ignore them.  */
  if (opt_format != 0)
    str_offset = file_entries_new_size;
  else
    str_offset = 0;

  str = strings;
  for (idx_old = 0, idx_new = 0, entry = entries; entry != NULL;
       entry = entry->next, ++idx_new)
    {
      /* First the library.  */
      if (opt_format != 2)
	{
	  file_entries->libs[idx_old].flags = entry->flags;
	  /* XXX: Actually we can optimize here and remove duplicates.  */
	  file_entries->libs[idx_old].key = str_offset + pad;
	}
      if (opt_format != 0)
	{
	  /* We could subtract file_entries_new_size from str_offset -
	     not doing so makes the code easier, the string table
	     always begins at the beginning of the the new cache
	     struct.  */
	  file_entries_new->libs[idx_new].flags = entry->flags;
	  file_entries_new->libs[idx_new].osversion = entry->osversion;
	  file_entries_new->libs[idx_new].hwcap = entry->hwcap;
	  file_entries_new->libs[idx_new].key = str_offset;
	}
      len = strlen (entry->lib);
      str = stpcpy (str, entry->lib);
      /* Account the final NUL.  */
      ++str;
      str_offset += len + 1;
      /* Then the path.  */
      if (opt_format != 2)
	file_entries->libs[idx_old].value = str_offset + pad;
      if (opt_format != 0)
	file_entries_new->libs[idx_new].value = str_offset;
      len = strlen (entry->path);
      str = stpcpy (str, entry->path);
      /* Account the final NUL.  */
      ++str;
      str_offset += len + 1;
      /* Ignore entries with hwcap for old format.  */
      if (entry->hwcap == 0)
	++idx_old;
    }

  /* Write out the cache.  */

  /* Write cache first to a temporary file and rename it later.  */
  temp_name = xmalloc (strlen (cache_name) + 2);
  sprintf (temp_name, "%s~", cache_name);
  /* First remove an old copy if it exists.  */
  if (unlink (temp_name) && errno != ENOENT)
    error (EXIT_FAILURE, errno, _("Can't remove old temporary cache file %s"),
	   temp_name);

  /* Create file.  */
  fd = open (temp_name, O_CREAT|O_WRONLY|O_TRUNC|O_NOFOLLOW,
	     S_IROTH|S_IRGRP|S_IRUSR|S_IWUSR);
  if (fd < 0)
    error (EXIT_FAILURE, errno, _("Can't create temporary cache file %s"),
	   temp_name);

  /* Write contents.  */
  if (opt_format != 2)
    {
      if (write (fd, file_entries, file_entries_size)
	  != (ssize_t)file_entries_size)
	error (EXIT_FAILURE, errno, _("Writing of cache data failed"));
    }
  if (opt_format != 0)
    {
      /* Align cache.  */
      if (opt_format != 2)
	{
	  char zero[pad];
	  if (write (fd, zero, pad) != (ssize_t)pad)
	    error (EXIT_FAILURE, errno, _("Writing of cache data failed"));
	}
      if (write (fd, file_entries_new, file_entries_new_size)
	  != (ssize_t)file_entries_new_size)
	error (EXIT_FAILURE, errno, _("Writing of cache data failed"));
    }

  if (write (fd, strings, total_strlen) != (ssize_t)total_strlen)
    error (EXIT_FAILURE, errno, _("Writing of cache data failed."));

  close (fd);

  /* Make sure user can always read cache file */
  if (chmod (temp_name, S_IROTH|S_IRGRP|S_IRUSR|S_IWUSR))
    error (EXIT_FAILURE, errno,
	   _("Changing access rights of %s to %#o failed"), temp_name,
	   S_IROTH|S_IRGRP|S_IRUSR|S_IWUSR);

  /* Move temporary to its final location.  */
  if (rename (temp_name, cache_name))
    error (EXIT_FAILURE, errno, _("Renaming of %s to %s failed"), temp_name,
	   cache_name);

  /* Free all allocated memory.  */
  free (file_entries);
  free (strings);

  while (entries)
    {
      entry = entries;
      free (entry->path);
      free (entry->lib);
      entries = entries->next;
      free (entry);
    }
}


/* Add one library to the cache.  */
void
add_to_cache (const char *path, const char *lib, int flags,
	      unsigned int osversion, uint64_t hwcap)
{
  struct cache_entry *new_entry, *ptr, *prev;
  char *full_path;
  int len, i;

  new_entry = (struct cache_entry *) xmalloc (sizeof (struct cache_entry));

  len = strlen (lib) + strlen (path) + 2;

  full_path = (char *) xmalloc (len);
  snprintf (full_path, len, "%s/%s", path, lib);

  new_entry->lib = xstrdup (lib);
  new_entry->path = full_path;
  new_entry->flags = flags;
  new_entry->osversion = osversion;
  new_entry->hwcap = hwcap;
  new_entry->bits_hwcap = 0;

  /* Count the number of bits set in the masked value.  */
  for (i = 0; (~((1ULL << i) - 1) & hwcap) != 0; ++i)
    if ((hwcap & (1ULL << i)) != 0)
      ++new_entry->bits_hwcap;


  /* Keep the list sorted - search for right place to insert.  */
  ptr = entries;
  prev = entries;
  while (ptr != NULL)
    {
      if (compare (ptr, new_entry) > 0)
	break;
      prev = ptr;
      ptr = ptr->next;
    }
  /* Is this the first entry?  */
  if (ptr == entries)
    {
      new_entry->next = entries;
      entries = new_entry;
    }
  else
    {
      new_entry->next = prev->next;
      prev->next = new_entry;
    }
}