glibc/elf/cache.c

464 lines
13 KiB
C

/* 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. */
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, 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
case 0:
break;
default:
printf (",%d", flag & FLAG_REQUIRED_MASK);
break;
}
if (hwcap != 0)
printf (", hwcap: 0x%" PRIx64, hwcap);
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)
&& !memcmp (cache_new->version, CACHE_VERSION,
sizeof CACHE_VERSION - 1))
{
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,
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].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;
}
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].hwcap = entry->hwcap;
file_entries_new->libs[idx_new].key = str_offset;
file_entries_new->libs[idx_new].__unused = 0;
}
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,
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->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;
}
}