diff options
Diffstat (limited to 'src/libs/3rdparty/libarchive/archive_write_disk_set_standard_lookup.c')
-rw-r--r-- | src/libs/3rdparty/libarchive/archive_write_disk_set_standard_lookup.c | 263 |
1 files changed, 263 insertions, 0 deletions
diff --git a/src/libs/3rdparty/libarchive/archive_write_disk_set_standard_lookup.c b/src/libs/3rdparty/libarchive/archive_write_disk_set_standard_lookup.c new file mode 100644 index 000000000..5fccdb9dc --- /dev/null +++ b/src/libs/3rdparty/libarchive/archive_write_disk_set_standard_lookup.c @@ -0,0 +1,263 @@ +/*- + * Copyright (c) 2003-2007 Tim Kientzle + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include "archive_platform.h" +__FBSDID("$FreeBSD: head/lib/libarchive/archive_write_disk_set_standard_lookup.c 201083 2009-12-28 02:09:57Z kientzle $"); + +#ifdef HAVE_SYS_TYPES_H +#include <sys/types.h> +#endif +#ifdef HAVE_ERRNO_H +#include <errno.h> +#endif +#ifdef HAVE_GRP_H +#include <grp.h> +#endif +#ifdef HAVE_PWD_H +#include <pwd.h> +#endif +#ifdef HAVE_STDLIB_H +#include <stdlib.h> +#endif +#ifdef HAVE_STRING_H +#include <string.h> +#endif + +#include "archive.h" +#include "archive_private.h" +#include "archive_read_private.h" +#include "archive_write_disk_private.h" + +struct bucket { + char *name; + int hash; + id_t id; +}; + +static const size_t cache_size = 127; +static unsigned int hash(const char *); +static int64_t lookup_gid(void *, const char *uname, int64_t); +static int64_t lookup_uid(void *, const char *uname, int64_t); +static void cleanup(void *); + +/* + * Installs functions that use getpwnam()/getgrnam()---along with + * a simple cache to accelerate such lookups---into the archive_write_disk + * object. This is in a separate file because getpwnam()/getgrnam() + * can pull in a LOT of library code (including NIS/LDAP functions, which + * pull in DNS resolvers, etc). This can easily top 500kB, which makes + * it inappropriate for some space-constrained applications. + * + * Applications that are size-sensitive may want to just use the + * real default functions (defined in archive_write_disk.c) that just + * use the uid/gid without the lookup. Or define your own custom functions + * if you prefer. + * + * TODO: Replace these hash tables with simpler move-to-front LRU + * lists with a bounded size (128 items?). The hash is a bit faster, + * but has a bad pathology in which it thrashes a single bucket. Even + * walking a list of 128 items is a lot faster than calling + * getpwnam()! + */ +int +archive_write_disk_set_standard_lookup(struct archive *a) +{ + struct bucket *ucache = calloc(cache_size, sizeof(struct bucket)); + struct bucket *gcache = calloc(cache_size, sizeof(struct bucket)); + if (ucache == NULL || gcache == NULL) { + free(ucache); + free(gcache); + return (ARCHIVE_FATAL); + } + archive_write_disk_set_group_lookup(a, gcache, lookup_gid, cleanup); + archive_write_disk_set_user_lookup(a, ucache, lookup_uid, cleanup); + return (ARCHIVE_OK); +} + +static int64_t +lookup_gid(void *private_data, const char *gname, int64_t gid) +{ + int h; + struct bucket *b; + struct bucket *gcache = (struct bucket *)private_data; + + /* If no gname, just use the gid provided. */ + if (gname == NULL || *gname == '\0') + return (gid); + + /* Try to find gname in the cache. */ + h = hash(gname); + b = &gcache[h % cache_size ]; + if (b->name != NULL && b->hash == h && strcmp(gname, b->name) == 0) + return ((gid_t)b->id); + + /* Free the cache slot for a new entry. */ + free(b->name); + b->name = strdup(gname); + /* Note: If strdup fails, that's okay; we just won't cache. */ + b->hash = h; +#if HAVE_GRP_H +# if HAVE_GETGRNAM_R + { + char _buffer[128]; + size_t bufsize = 128; + char *buffer = _buffer; + char *allocated = NULL; + struct group grent, *result; + int r; + + for (;;) { + result = &grent; /* Old getgrnam_r ignores last arg. */ + r = getgrnam_r(gname, &grent, buffer, bufsize, &result); + if (r == 0) + break; + if (r != ERANGE) + break; + bufsize *= 2; + free(allocated); + allocated = malloc(bufsize); + if (allocated == NULL) + break; + buffer = allocated; + } + if (result != NULL) + gid = result->gr_gid; + free(allocated); + } +# else /* HAVE_GETGRNAM_R */ + { + struct group *result; + + result = getgrnam(gname); + if (result != NULL) + gid = result->gr_gid; + } +# endif /* HAVE_GETGRNAM_R */ +#elif defined(_WIN32) && !defined(__CYGWIN__) + /* TODO: do a gname->gid lookup for Windows. */ +#else + #error No way to perform gid lookups on this platform +#endif + b->id = (gid_t)gid; + + return (gid); +} + +static int64_t +lookup_uid(void *private_data, const char *uname, int64_t uid) +{ + int h; + struct bucket *b; + struct bucket *ucache = (struct bucket *)private_data; + + /* If no uname, just use the uid provided. */ + if (uname == NULL || *uname == '\0') + return (uid); + + /* Try to find uname in the cache. */ + h = hash(uname); + b = &ucache[h % cache_size ]; + if (b->name != NULL && b->hash == h && strcmp(uname, b->name) == 0) + return ((uid_t)b->id); + + /* Free the cache slot for a new entry. */ + free(b->name); + b->name = strdup(uname); + /* Note: If strdup fails, that's okay; we just won't cache. */ + b->hash = h; +#if HAVE_PWD_H +# if HAVE_GETPWNAM_R + { + char _buffer[128]; + size_t bufsize = 128; + char *buffer = _buffer; + char *allocated = NULL; + struct passwd pwent, *result; + int r; + + for (;;) { + result = &pwent; /* Old getpwnam_r ignores last arg. */ + r = getpwnam_r(uname, &pwent, buffer, bufsize, &result); + if (r == 0) + break; + if (r != ERANGE) + break; + bufsize *= 2; + free(allocated); + allocated = malloc(bufsize); + if (allocated == NULL) + break; + buffer = allocated; + } + if (result != NULL) + uid = result->pw_uid; + free(allocated); + } +# else /* HAVE_GETPWNAM_R */ + { + struct passwd *result; + + result = getpwnam(uname); + if (result != NULL) + uid = result->pw_uid; + } +#endif /* HAVE_GETPWNAM_R */ +#elif defined(_WIN32) && !defined(__CYGWIN__) + /* TODO: do a uname->uid lookup for Windows. */ +#else + #error No way to look up uids on this platform +#endif + b->id = (uid_t)uid; + + return (uid); +} + +static void +cleanup(void *private) +{ + size_t i; + struct bucket *cache = (struct bucket *)private; + + for (i = 0; i < cache_size; i++) + free(cache[i].name); + free(cache); +} + + +static unsigned int +hash(const char *p) +{ + /* A 32-bit version of Peter Weinberger's (PJW) hash algorithm, + as used by ELF for hashing function names. */ + unsigned g, h = 0; + while (*p != '\0') { + h = (h << 4) + *p++; + if ((g = h & 0xF0000000) != 0) { + h ^= g >> 24; + h &= 0x0FFFFFFF; + } + } + return h; +} |