glibc/elf/cache.c
Ulrich Drepper 25ee87d6f1 Update.
2000-04-10  Thorsten Kukuk  <kukuk@suse.de>

	* elf/cache.c (save_cache): Make sure /etc/ld.so.cache is mode 644.
2000-04-10 16:22:52 +00:00

369 lines
9.1 KiB
C

/* Copyright (C) 1999, 2000 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. */
#define _GNU_SOURCE 1
#include <assert.h>
#include <errno.h>
#include <error.h>
#include <dirent.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"
#define CACHEMAGIC "ld.so-1.7.0"
struct cache_entry
{
char *lib;
char *path;
int flags;
struct cache_entry *next;
};
struct file_entry
{
int flags; /* This is 1 for an ELF library. */
unsigned int key, value; /* String table indices. */
};
struct cache_file
{
char magic[sizeof CACHEMAGIC - 1];
unsigned int nlibs;
struct file_entry libs[0];
};
/* 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, 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
case 0:
break;
default:
fprintf (stdout, ",%d", flag & FLAG_REQUIRED_MASK);
break;
}
printf (") => %s\n", key);
}
/* Print the whole cache file. */
void
print_cache (const char *cache_name)
{
size_t cache_size;
struct stat st;
int fd;
unsigned int i;
struct cache_file *cache;
const char *cache_data;
fd = open (cache_name, O_RDONLY);
if (fd < 0)
error (EXIT_FAILURE, errno, _("Can't open cache file %s\n"), cache_name);
if (fstat (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)
|| memcmp (cache->magic, CACHEMAGIC, sizeof CACHEMAGIC - 1))
return;
/* This is where the strings start. */
cache_data = (const char *) &cache->libs[cache->nlibs];
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,
cache_data + cache->libs[i].value);
/* Cleanup. */
munmap (cache, cache_size);
close (fd);
}
/* Initialize cache data structures. */
void
init_cache (void)
{
entries = NULL;
}
/* Helper function which must match the one in the dynamic linker, so that
we rely on the same sort order. */
int
cache_libcmp (const char *p1, const char *p2)
{
while (*p1 != '\0')
{
if (*p1 >= '0' && *p1 <= '9')
{
if (*p2 >= '0' && *p2 <= '9')
{
/* Must compare this numerically. */
int val1;
int val2;
val1 = *p1++ - '0';
val2 = *p2++ - '0';
while (*p1 >= '0' && *p1 <= '9')
val1 = val1 * 10 + *p1++ - '0';
while (*p2 >= '0' && *p2 <= '9')
val2 = val2 * 10 + *p2++ - '0';
if (val1 != val2)
return val1 - val2;
}
else
return 1;
}
else if (*p2 >= '0' && *p2 <= '9')
return -1;
else if (*p1 != *p2)
return *p1 - *p2;
else
{
++p1;
++p2;
}
}
return *p1 - *p2;
}
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 = cache_libcmp (e2->lib, e1->lib);
if (res == 0)
{
if (e1->flags < e2->flags)
return 1;
else if (e1->flags > e2->flags)
return -1;
}
return res;
}
/* Save the contents of the cache. */
void
save_cache (const char *cache_name)
{
struct cache_entry *entry;
int i, fd;
size_t total_strlen, len;
char *strings, *str, *temp_name;
struct cache_file *file_entries;
size_t file_entries_size;
unsigned int str_offset;
/* Number of cache entries. */
int cache_entry_count = 0;
/* The cache entries are sorted already, save them in this order. */
/* Count the length of all strings. */
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;
}
/* Create the on disk cache structure. */
/* First an array for all strings. */
strings = (char *)xmalloc (total_strlen + 1);
/* And the list of all entries. */
file_entries_size = sizeof (struct cache_file)
+ cache_entry_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_count;
str_offset = 0;
str = strings;
for (i = 0, entry = entries; entry != NULL; entry = entry->next, ++i)
{
file_entries->libs[i].flags = entry->flags;
/* First the library. */
/* XXX: Actually we can optimize here and remove duplicates. */
file_entries->libs[i].key = str_offset;
len = strlen (entry->lib);
str = stpcpy (str, entry->lib);
/* Account the final NUL. */
++str;
str_offset += len + 1;
/* Then the path. */
file_entries->libs[i].value = str_offset;
len = strlen (entry->path);
str = stpcpy (str, entry->path);
/* Account the final NUL. */
++str;
str_offset += len + 1;
}
assert (str_offset == total_strlen);
/* 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, 0644);
if (fd < 0)
error (EXIT_FAILURE, errno, _("Can't create temporary cache file %s"),
temp_name);
/* Write contents. */
if (write (fd, file_entries, file_entries_size) != (ssize_t)file_entries_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, 0644))
error (EXIT_FAILURE, errno,
_("Changing access rights of %s to 0644 failed"), temp_name);
/* 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)
{
struct cache_entry *new_entry, *ptr, *prev;
char *full_path;
int len;
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;
/* 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;
}
}