diff options
Diffstat (limited to 'bdb/os/os_fid.c')
| -rw-r--r-- | bdb/os/os_fid.c | 148 |
1 files changed, 0 insertions, 148 deletions
diff --git a/bdb/os/os_fid.c b/bdb/os/os_fid.c deleted file mode 100644 index 125e6f0712c..00000000000 --- a/bdb/os/os_fid.c +++ /dev/null @@ -1,148 +0,0 @@ -/*- - * See the file LICENSE for redistribution information. - * - * Copyright (c) 1996-2002 - * Sleepycat Software. All rights reserved. - */ - -#include "db_config.h" - -#ifndef lint -static const char revid[] = "$Id: os_fid.c,v 11.14 2002/08/26 14:37:38 margo Exp $"; -#endif /* not lint */ - -#ifndef NO_SYSTEM_INCLUDES -#include <sys/types.h> -#include <sys/stat.h> - -#if TIME_WITH_SYS_TIME -#include <sys/time.h> -#include <time.h> -#else -#if HAVE_SYS_TIME_H -#include <sys/time.h> -#else -#include <time.h> -#endif -#endif - -#include <stdlib.h> -#include <string.h> -#include <unistd.h> -#endif - -#include "db_int.h" - -#define SERIAL_INIT 0 -static u_int32_t fid_serial = SERIAL_INIT; - -/* - * __os_fileid -- - * Return a unique identifier for a file. The structure - * of a fileid is: ino(4) dev(4) time(4) pid(4) extra(4). - * For real files, which have a backing inode and device, the first - * 16 bytes are filled in and the extra bytes are left 0. For - * temporary files, the inode and device fields are left blank and - * the extra four bytes are filled in with a random value. - * - * PUBLIC: int __os_fileid __P((DB_ENV *, const char *, int, u_int8_t *)); - */ -int -__os_fileid(dbenv, fname, unique_okay, fidp) - DB_ENV *dbenv; - const char *fname; - int unique_okay; - u_int8_t *fidp; -{ - struct stat sb; - size_t i; - int ret; - u_int32_t tmp; - u_int8_t *p; - - /* Clear the buffer. */ - memset(fidp, 0, DB_FILE_ID_LEN); - - /* On POSIX/UNIX, use a dev/inode pair. */ -retry: -#ifdef HAVE_VXWORKS - if (stat((char *)fname, &sb) != 0) { -#else - if (stat(fname, &sb) != 0) { -#endif - if ((ret = __os_get_errno()) == EINTR) - goto retry; - __db_err(dbenv, "%s: %s", fname, strerror(ret)); - return (ret); - } - - /* - * Initialize/increment the serial number we use to help avoid - * fileid collisions. Note that we don't bother with locking; - * it's unpleasant to do from down in here, and if we race on - * this no real harm will be done, since the finished fileid - * has so many other components. - * - * We increment by 100000 on each call as a simple way of - * randomizing; simply incrementing seems potentially less useful - * if pids are also simply incremented, since this is process-local - * and we may be one of a set of processes starting up. 100000 - * pushes us out of pid space on most platforms, and has few - * interesting properties in base 2. - */ - if (fid_serial == SERIAL_INIT) - __os_id(&fid_serial); - else - fid_serial += 100000; - - /* - * !!! - * Nothing is ever big enough -- on Sparc V9, st_ino, st_dev and the - * time_t types are all 8 bytes. As DB_FILE_ID_LEN is only 20 bytes, - * we convert to a (potentially) smaller fixed-size type and use it. - * - * We don't worry about byte sexing or the actual variable sizes. - * - * When this routine is called from the DB access methods, it's only - * called once -- whatever ID is generated when a database is created - * is stored in the database file's metadata, and that is what is - * saved in the mpool region's information to uniquely identify the - * file. - * - * When called from the mpool layer this routine will be called each - * time a new thread of control wants to share the file, which makes - * things tougher. As far as byte sexing goes, since the mpool region - * lives on a single host, there's no issue of that -- the entire - * region is byte sex dependent. As far as variable sizes go, we make - * the simplifying assumption that 32-bit and 64-bit processes will - * get the same 32-bit values if we truncate any returned 64-bit value - * to a 32-bit value. When we're called from the mpool layer, though, - * we need to be careful not to include anything that isn't - * reproducible for a given file, such as the timestamp or serial - * number. - */ - tmp = (u_int32_t)sb.st_ino; - for (p = (u_int8_t *)&tmp, i = sizeof(u_int32_t); i > 0; --i) - *fidp++ = *p++; - - tmp = (u_int32_t)sb.st_dev; - for (p = (u_int8_t *)&tmp, i = sizeof(u_int32_t); i > 0; --i) - *fidp++ = *p++; - - if (unique_okay) { - /* - * We want the number of seconds, not the high-order 0 bits, - * so convert the returned time_t to a (potentially) smaller - * fixed-size type. - */ - tmp = (u_int32_t)time(NULL); - for (p = (u_int8_t *)&tmp, i = sizeof(u_int32_t); i > 0; --i) - *fidp++ = *p++; - - for (p = (u_int8_t *)&fid_serial, i = sizeof(u_int32_t); - i > 0; --i) - *fidp++ = *p++; - } - - return (0); -} |