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-rw-r--r--REORG.TODO/elf/cache.c829
1 files changed, 829 insertions, 0 deletions
diff --git a/REORG.TODO/elf/cache.c b/REORG.TODO/elf/cache.c
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index 0000000000..a76f89281d
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+++ b/REORG.TODO/elf/cache.c
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+/* Copyright (C) 1999-2017 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Andreas Jaeger <aj@suse.de>, 1999.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published
+ by the Free Software Foundation; version 2 of the License, or
+ (at your option) any later version.
+
+ This program 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 General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, see <http://www.gnu.org/licenses/>. */
+
+#include <errno.h>
+#include <error.h>
+#include <dirent.h>
+#include <inttypes.h>
+#include <libgen.h>
+#include <libintl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <stdint.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)
+ {
+ case FLAG_SPARC_LIB64:
+ fputs (",64bit", stdout);
+ break;
+ case FLAG_IA64_LIB64:
+ fputs (",IA-64", stdout);
+ break;
+ case FLAG_X8664_LIB64:
+ fputs (",x86-64", stdout);
+ break;
+ case FLAG_S390_LIB64:
+ fputs (",64bit", stdout);
+ break;
+ case FLAG_POWERPC_LIB64:
+ fputs (",64bit", stdout);
+ break;
+ case FLAG_MIPS64_LIBN32:
+ fputs (",N32", stdout);
+ break;
+ case FLAG_MIPS64_LIBN64:
+ fputs (",64bit", stdout);
+ break;
+ case FLAG_X8664_LIBX32:
+ fputs (",x32", stdout);
+ break;
+ case FLAG_ARM_LIBHF:
+ fputs (",hard-float", stdout);
+ break;
+ case FLAG_AARCH64_LIB64:
+ fputs (",AArch64", stdout);
+ break;
+ /* Uses the ARM soft-float ABI. */
+ case FLAG_ARM_LIBSF:
+ fputs (",soft-float", stdout);
+ break;
+ case FLAG_MIPS_LIB32_NAN2008:
+ fputs (",nan2008", stdout);
+ break;
+ case FLAG_MIPS64_LIBN32_NAN2008:
+ fputs (",N32,nan2008", stdout);
+ break;
+ case FLAG_MIPS64_LIBN64_NAN2008:
+ fputs (",64bit,nan2008", stdout);
+ break;
+ case 0:
+ break;
+ default:
+ printf (",%d", flag & FLAG_REQUIRED_MASK);
+ break;
+ }
+ if (hwcap != 0)
+ printf (", hwcap: %#.16" PRIx64, hwcap);
+ if (osversion != 0)
+ {
+ static const char *const abi_tag_os[] =
+ {
+ [0] = "Linux",
+ [1] = "Hurd",
+ [2] = "Solaris",
+ [3] = "FreeBSD",
+ [4] = "kNetBSD",
+ [5] = "Syllable",
+ [6] = N_("Unknown OS")
+ };
+#define MAXTAG (sizeof abi_tag_os / sizeof abi_tag_os[0] - 1)
+ unsigned int os = osversion >> 24;
+
+ printf (_(", OS ABI: %s %d.%d.%d"),
+ _(abi_tag_os[os > MAXTAG ? MAXTAG : 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)
+{
+ int fd = open (cache_name, O_RDONLY);
+ if (fd < 0)
+ error (EXIT_FAILURE, errno, _("Can't open cache file %s\n"), cache_name);
+
+ struct stat64 st;
+ if (fstat64 (fd, &st) < 0
+ /* No need to map the file if it is empty. */
+ || st.st_size == 0)
+ {
+ close (fd);
+ return;
+ }
+
+ struct cache_file *cache
+ = mmap (NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
+ if (cache == MAP_FAILED)
+ error (EXIT_FAILURE, errno, _("mmap of cache file failed.\n"));
+
+ size_t cache_size = st.st_size;
+ if (cache_size < sizeof (struct cache_file))
+ error (EXIT_FAILURE, 0, _("File is not a cache file.\n"));
+
+ struct cache_file_new *cache_new = NULL;
+ const char *cache_data;
+ int format = 0;
+
+ 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 (unsigned int 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 (unsigned int 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)
+{
+ /* We need to swap entries here to get the correct sort order. */
+ int 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)
+{
+ /* 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. */
+ size_t total_strlen = 0;
+ struct cache_entry *entry;
+ /* Number of cache entries. */
+ int cache_entry_count = 0;
+ /* Number of normal cache entries. */
+ int cache_entry_old_count = 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. */
+ struct cache_file *file_entries = NULL;
+ size_t file_entries_size = 0;
+
+ if (opt_format != 2)
+ {
+ /* struct cache_file_new is 64-bit aligned on some arches while
+ only 32-bit aligned on other arches. Duplicate last old
+ cache entry so that new cache in ld.so.cache can be used by
+ both. */
+ if (opt_format != 0)
+ cache_entry_old_count = (cache_entry_old_count + 1) & ~1;
+
+ /* 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 = 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;
+ }
+
+ struct cache_file_new *file_entries_new = NULL;
+ size_t file_entries_new_size = 0;
+
+ 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 = 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 for alignment of cache_file_new. */
+ size_t 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. */
+ unsigned int str_offset;
+ if (opt_format != 0)
+ str_offset = file_entries_new_size;
+ else
+ str_offset = 0;
+
+ /* An array for all strings. */
+ char *strings = xmalloc (total_strlen);
+ char *str = strings;
+ int idx_old;
+ int idx_new;
+
+ for (idx_old = 0, idx_new = 0, entry = entries; entry != NULL;
+ entry = entry->next, ++idx_new)
+ {
+ /* First the library. */
+ if (opt_format != 2 && entry->hwcap == 0)
+ {
+ 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 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;
+ }
+
+ size_t len = strlen (entry->lib) + 1;
+ str = mempcpy (str, entry->lib, len);
+ str_offset += len;
+ /* Then the path. */
+ if (opt_format != 2 && entry->hwcap == 0)
+ 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) + 1;
+ str = mempcpy (str, entry->path, len);
+ str_offset += len;
+ /* Ignore entries with hwcap for old format. */
+ if (entry->hwcap == 0)
+ ++idx_old;
+ }
+
+ /* Duplicate last old cache entry if needed. */
+ if (opt_format != 2
+ && idx_old < cache_entry_old_count)
+ file_entries->libs[idx_old] = file_entries->libs[idx_old - 1];
+
+ /* Write out the cache. */
+
+ /* Write cache first to a temporary file and rename it later. */
+ char *temp_name = xmalloc (strlen (cache_name) + 2);
+ sprintf (temp_name, "%s~", cache_name);
+
+ /* Create file. */
+ int fd = open (temp_name, O_CREAT|O_WRONLY|O_TRUNC|O_NOFOLLOW,
+ 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];
+ memset (zero, '\0', 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
+ || close (fd))
+ error (EXIT_FAILURE, errno, _("Writing of cache data failed"));
+
+ /* 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_new);
+ free (file_entries);
+ free (strings);
+
+ while (entries)
+ {
+ entry = entries;
+ 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)
+{
+ size_t liblen = strlen (lib) + 1;
+ size_t len = liblen + strlen (path) + 1;
+ struct cache_entry *new_entry
+ = xmalloc (sizeof (struct cache_entry) + liblen + len);
+
+ new_entry->lib = memcpy ((char *) (new_entry + 1), lib, liblen);
+ new_entry->path = new_entry->lib + liblen;
+ snprintf (new_entry->path, len, "%s/%s", path, lib);
+ 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 (size_t i = 0;
+ (~((1ULL << i) - 1) & hwcap) != 0 && i < 8 * sizeof (hwcap); ++i)
+ if ((hwcap & (1ULL << i)) != 0)
+ ++new_entry->bits_hwcap;
+
+
+ /* Keep the list sorted - search for right place to insert. */
+ struct cache_entry *ptr = entries;
+ struct cache_entry *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;
+ }
+}
+
+
+/* Auxiliary cache. */
+
+struct aux_cache_entry_id
+{
+ uint64_t ino;
+ uint64_t ctime;
+ uint64_t size;
+ uint64_t dev;
+};
+
+struct aux_cache_entry
+{
+ struct aux_cache_entry_id id;
+ int flags;
+ unsigned int osversion;
+ int used;
+ char *soname;
+ struct aux_cache_entry *next;
+};
+
+#define AUX_CACHEMAGIC "glibc-ld.so.auxcache-1.0"
+
+struct aux_cache_file_entry
+{
+ struct aux_cache_entry_id id; /* Unique id of entry. */
+ int32_t flags; /* This is 1 for an ELF library. */
+ uint32_t soname; /* String table indice. */
+ uint32_t osversion; /* Required OS version. */
+ int32_t pad;
+};
+
+/* ldconfig maintains an auxiliary cache file that allows
+ only reading those libraries that have changed since the last iteration.
+ For this for each library some information is cached in the auxiliary
+ cache. */
+struct aux_cache_file
+{
+ char magic[sizeof AUX_CACHEMAGIC - 1];
+ uint32_t nlibs; /* Number of entries. */
+ uint32_t len_strings; /* Size of string table. */
+ struct aux_cache_file_entry libs[0]; /* Entries describing libraries. */
+ /* After this the string table of size len_strings is found. */
+};
+
+static const unsigned int primes[] =
+{
+ 1021, 2039, 4093, 8191, 16381, 32749, 65521, 131071, 262139,
+ 524287, 1048573, 2097143, 4194301, 8388593, 16777213, 33554393,
+ 67108859, 134217689, 268435399, 536870909, 1073741789, 2147483647
+};
+
+static size_t aux_hash_size;
+static struct aux_cache_entry **aux_hash;
+
+/* Simplistic hash function for aux_cache_entry_id. */
+static unsigned int
+aux_cache_entry_id_hash (struct aux_cache_entry_id *id)
+{
+ uint64_t ret = ((id->ino * 11 + id->ctime) * 11 + id->size) * 11 + id->dev;
+ return ret ^ (ret >> 32);
+}
+
+static size_t nextprime (size_t x)
+{
+ for (unsigned int i = 0; i < sizeof (primes) / sizeof (primes[0]); ++i)
+ if (primes[i] >= x)
+ return primes[i];
+ return x;
+}
+
+void
+init_aux_cache (void)
+{
+ aux_hash_size = primes[3];
+ aux_hash = xcalloc (aux_hash_size, sizeof (struct aux_cache_entry *));
+}
+
+int
+search_aux_cache (struct stat64 *stat_buf, int *flags,
+ unsigned int *osversion, char **soname)
+{
+ struct aux_cache_entry_id id;
+ id.ino = (uint64_t) stat_buf->st_ino;
+ id.ctime = (uint64_t) stat_buf->st_ctime;
+ id.size = (uint64_t) stat_buf->st_size;
+ id.dev = (uint64_t) stat_buf->st_dev;
+
+ unsigned int hash = aux_cache_entry_id_hash (&id);
+ struct aux_cache_entry *entry;
+ for (entry = aux_hash[hash % aux_hash_size]; entry; entry = entry->next)
+ if (id.ino == entry->id.ino
+ && id.ctime == entry->id.ctime
+ && id.size == entry->id.size
+ && id.dev == entry->id.dev)
+ {
+ *flags = entry->flags;
+ *osversion = entry->osversion;
+ if (entry->soname != NULL)
+ *soname = xstrdup (entry->soname);
+ else
+ *soname = NULL;
+ entry->used = 1;
+ return 1;
+ }
+
+ return 0;
+}
+
+static void
+insert_to_aux_cache (struct aux_cache_entry_id *id, int flags,
+ unsigned int osversion, const char *soname, int used)
+{
+ size_t hash = aux_cache_entry_id_hash (id) % aux_hash_size;
+ struct aux_cache_entry *entry;
+ for (entry = aux_hash[hash]; entry; entry = entry->next)
+ if (id->ino == entry->id.ino
+ && id->ctime == entry->id.ctime
+ && id->size == entry->id.size
+ && id->dev == entry->id.dev)
+ abort ();
+
+ size_t len = soname ? strlen (soname) + 1 : 0;
+ entry = xmalloc (sizeof (struct aux_cache_entry) + len);
+ entry->id = *id;
+ entry->flags = flags;
+ entry->osversion = osversion;
+ entry->used = used;
+ if (soname != NULL)
+ entry->soname = memcpy ((char *) (entry + 1), soname, len);
+ else
+ entry->soname = NULL;
+ entry->next = aux_hash[hash];
+ aux_hash[hash] = entry;
+}
+
+void
+add_to_aux_cache (struct stat64 *stat_buf, int flags,
+ unsigned int osversion, const char *soname)
+{
+ struct aux_cache_entry_id id;
+ id.ino = (uint64_t) stat_buf->st_ino;
+ id.ctime = (uint64_t) stat_buf->st_ctime;
+ id.size = (uint64_t) stat_buf->st_size;
+ id.dev = (uint64_t) stat_buf->st_dev;
+ insert_to_aux_cache (&id, flags, osversion, soname, 1);
+}
+
+/* Load auxiliary cache to search for unchanged entries. */
+void
+load_aux_cache (const char *aux_cache_name)
+{
+ int fd = open (aux_cache_name, O_RDONLY);
+ if (fd < 0)
+ {
+ init_aux_cache ();
+ return;
+ }
+
+ struct stat64 st;
+ if (fstat64 (fd, &st) < 0 || st.st_size < sizeof (struct aux_cache_file))
+ {
+ close (fd);
+ init_aux_cache ();
+ return;
+ }
+
+ size_t aux_cache_size = st.st_size;
+ struct aux_cache_file *aux_cache
+ = mmap (NULL, aux_cache_size, PROT_READ, MAP_PRIVATE, fd, 0);
+ if (aux_cache == MAP_FAILED
+ || aux_cache_size < sizeof (struct aux_cache_file)
+ || memcmp (aux_cache->magic, AUX_CACHEMAGIC, sizeof AUX_CACHEMAGIC - 1)
+ || aux_cache_size != (sizeof(struct aux_cache_file) +
+ aux_cache->nlibs * sizeof(struct aux_cache_file_entry) +
+ aux_cache->len_strings))
+ {
+ close (fd);
+ init_aux_cache ();
+ return;
+ }
+
+ aux_hash_size = nextprime (aux_cache->nlibs);
+ aux_hash = xcalloc (aux_hash_size, sizeof (struct aux_cache_entry *));
+
+ const char *aux_cache_data
+ = (const char *) &aux_cache->libs[aux_cache->nlibs];
+ for (unsigned int i = 0; i < aux_cache->nlibs; ++i)
+ insert_to_aux_cache (&aux_cache->libs[i].id,
+ aux_cache->libs[i].flags,
+ aux_cache->libs[i].osversion,
+ aux_cache->libs[i].soname == 0
+ ? NULL : aux_cache_data + aux_cache->libs[i].soname,
+ 0);
+
+ munmap (aux_cache, aux_cache_size);
+ close (fd);
+}
+
+/* Save the contents of the auxiliary cache. */
+void
+save_aux_cache (const char *aux_cache_name)
+{
+ /* Count the length of all sonames. We start with empty string. */
+ size_t total_strlen = 1;
+ /* Number of cache entries. */
+ int cache_entry_count = 0;
+
+ for (size_t i = 0; i < aux_hash_size; ++i)
+ for (struct aux_cache_entry *entry = aux_hash[i];
+ entry != NULL; entry = entry->next)
+ if (entry->used)
+ {
+ ++cache_entry_count;
+ if (entry->soname != NULL)
+ total_strlen += strlen (entry->soname) + 1;
+ }
+
+ /* Auxiliary cache. */
+ size_t file_entries_size
+ = sizeof (struct aux_cache_file)
+ + cache_entry_count * sizeof (struct aux_cache_file_entry);
+ struct aux_cache_file *file_entries
+ = xmalloc (file_entries_size + total_strlen);
+
+ /* Fill in the header of the auxiliary cache. */
+ memset (file_entries, '\0', sizeof (struct aux_cache_file));
+ memcpy (file_entries->magic, AUX_CACHEMAGIC, sizeof AUX_CACHEMAGIC - 1);
+
+ file_entries->nlibs = cache_entry_count;
+ file_entries->len_strings = total_strlen;
+
+ /* Initial String offset for auxiliary cache is always after the
+ special empty string. */
+ unsigned int str_offset = 1;
+
+ /* An array for all strings. */
+ char *str = (char *) file_entries + file_entries_size;
+ *str++ = '\0';
+
+ size_t idx = 0;
+ for (size_t i = 0; i < aux_hash_size; ++i)
+ for (struct aux_cache_entry *entry = aux_hash[i];
+ entry != NULL; entry = entry->next)
+ if (entry->used)
+ {
+ file_entries->libs[idx].id = entry->id;
+ file_entries->libs[idx].flags = entry->flags;
+ if (entry->soname == NULL)
+ file_entries->libs[idx].soname = 0;
+ else
+ {
+ file_entries->libs[idx].soname = str_offset;
+
+ size_t len = strlen (entry->soname) + 1;
+ str = mempcpy (str, entry->soname, len);
+ str_offset += len;
+ }
+ file_entries->libs[idx].osversion = entry->osversion;
+ file_entries->libs[idx++].pad = 0;
+ }
+
+ /* Write out auxiliary cache file. */
+ /* Write auxiliary cache first to a temporary file and rename it later. */
+
+ char *temp_name = xmalloc (strlen (aux_cache_name) + 2);
+ sprintf (temp_name, "%s~", aux_cache_name);
+
+ /* Check that directory exists and create if needed. */
+ char *dir = strdupa (aux_cache_name);
+ dir = dirname (dir);
+
+ struct stat64 st;
+ if (stat64 (dir, &st) < 0)
+ {
+ if (mkdir (dir, 0700) < 0)
+ goto out_fail;
+ }
+
+ /* Create file. */
+ int fd = open (temp_name, O_CREAT|O_WRONLY|O_TRUNC|O_NOFOLLOW,
+ S_IRUSR|S_IWUSR);
+ if (fd < 0)
+ goto out_fail;
+
+ if (write (fd, file_entries, file_entries_size + total_strlen)
+ != (ssize_t) (file_entries_size + total_strlen)
+ || close (fd))
+ {
+ unlink (temp_name);
+ goto out_fail;
+ }
+
+ /* Move temporary to its final location. */
+ if (rename (temp_name, aux_cache_name))
+ unlink (temp_name);
+
+out_fail:
+ /* Free allocated memory. */
+ free (temp_name);
+ free (file_entries);
+}