diff options
Diffstat (limited to 'db2/common/db_region.c')
-rw-r--r-- | db2/common/db_region.c | 77 |
1 files changed, 47 insertions, 30 deletions
diff --git a/db2/common/db_region.c b/db2/common/db_region.c index 4fc603a2b0..02d939e3e6 100644 --- a/db2/common/db_region.c +++ b/db2/common/db_region.c @@ -43,7 +43,7 @@ #include "config.h" #ifndef lint -static const char sccsid[] = "@(#)db_region.c 10.18 (Sleepycat) 11/28/97"; +static const char sccsid[] = "@(#)db_region.c 10.21 (Sleepycat) 1/16/98"; #endif /* not lint */ #ifndef NO_SYSTEM_INCLUDES @@ -168,6 +168,8 @@ __db_rinit(dbenv, rp, fd, size, lock_region) { int ret; + COMPQUIET(dbenv, NULL); + /* * Initialize the common information. * @@ -190,6 +192,12 @@ __db_rinit(dbenv, rp, fd, size, lock_region) * been initialized in which case an attempt to get it could lead to * random behavior. If the version number isn't there (the file size * is too small) or it's 0, we know that the region is being created. + * + * We also make sure to check the return of __db_mutex_lock() here, + * even though we don't usually check elsewhere. This is the first + * lock we attempt to acquire, and if it fails we have to know. (It + * can fail -- SunOS, using fcntl(2) for locking, with an in-memory + * filesystem specified as the database home.) */ __db_mutex_init(&rp->lock, MUTEX_LOCK_OFFSET(rp, &rp->lock)); if (lock_region && (ret = __db_mutex_lock(&rp->lock, fd)) != 0) @@ -219,7 +227,8 @@ __db_ropen(dbenv, appname, path, file, flags, fdp, retp) void *retp; { RLAYOUT *rp; - off_t size1, size2; + size_t size; + u_int32_t mbytes, bytes; int fd, ret; char *name; @@ -251,19 +260,20 @@ __db_ropen(dbenv, appname, path, file, flags, fdp, retp) * flatly impossible. Hope that mmap fails if the file is too large. * */ - if ((ret = __db_ioinfo(name, fd, &size1, NULL)) != 0) { + if ((ret = __db_ioinfo(name, fd, &mbytes, &bytes, NULL)) != 0) { __db_err(dbenv, "%s: %s", name, strerror(ret)); goto err2; } + size = mbytes * MEGABYTE + bytes; /* Check to make sure the first block has been written. */ - if ((size_t)size1 < sizeof(RLAYOUT)) { + if (size < sizeof(RLAYOUT)) { ret = EAGAIN; goto err2; } /* Map in whatever is there. */ - if ((ret = __db_rmap(dbenv, fd, size1, &rp)) != 0) + if ((ret = __db_rmap(dbenv, fd, size, &rp)) != 0) goto err2; /* @@ -284,11 +294,11 @@ __db_ropen(dbenv, appname, path, file, flags, fdp, retp) * getting the size of the file and checking the major version. Check * to make sure we got the entire file. */ - if ((ret = __db_ioinfo(name, fd, &size2, NULL)) != 0) { + if ((ret = __db_ioinfo(name, fd, &mbytes, &bytes, NULL)) != 0) { __db_err(dbenv, "%s: %s", name, strerror(ret)); goto err1; } - if (size1 != size2) { + if (size != mbytes * MEGABYTE + bytes) { ret = EAGAIN; goto err1; } @@ -490,11 +500,9 @@ __db_rgrow(dbenv, fd, incr) int fd; size_t incr; { -#ifdef MMAP_INIT_NEEDED size_t i; -#endif ssize_t nw; - int ret; + int mmap_init_needed, ret; char buf[__DB_VMPAGESIZE]; /* Seek to the end of the region. */ @@ -506,33 +514,42 @@ __db_rgrow(dbenv, fd, incr) /* * Historically, some systems required that all of the bytes of the - * region be written before you could mmap it and access it randomly. + * region be written before it could be mmapped and accessed randomly. + * + * Windows/95 doesn't have that problem, but it leaves file contents + * uninitialized. Win/NT apparently initializes them. */ #ifdef MMAP_INIT_NEEDED - /* Extend the region by writing each new page. */ - for (i = 0; i < incr; i += __DB_VMPAGESIZE) { + mmap_init_needed = 1; +#else + mmap_init_needed = __os_oldwin(); +#endif + if (mmap_init_needed) + /* Extend the region by writing each new page. */ + for (i = 0; i < incr; i += __DB_VMPAGESIZE) { + if ((ret = __db_write(fd, buf, sizeof(buf), &nw)) != 0) + goto err; + if (nw != sizeof(buf)) + goto eio; + } + else { + /* + * Extend the region by writing the last page. + * + * Round off the increment to the next page boundary. + */ + incr += __DB_VMPAGESIZE - 1; + incr -= incr % __DB_VMPAGESIZE; + + /* Write the last page, not the page after the last. */ + if ((ret = + __db_seek(fd, 0, 0, incr - __DB_VMPAGESIZE, SEEK_CUR)) != 0) + goto err; if ((ret = __db_write(fd, buf, sizeof(buf), &nw)) != 0) goto err; if (nw != sizeof(buf)) goto eio; } -#else - /* - * Extend the region by writing the last page. - * - * Round off the increment to the next page boundary. - */ - incr += __DB_VMPAGESIZE - 1; - incr -= incr % __DB_VMPAGESIZE; - - /* Write the last page, not the page after the last. */ - if ((ret = __db_seek(fd, 0, 0, incr - __DB_VMPAGESIZE, SEEK_CUR)) != 0) - goto err; - if ((ret = __db_write(fd, buf, sizeof(buf), &nw)) != 0) - goto err; - if (nw != sizeof(buf)) - goto eio; -#endif return (0); eio: ret = EIO; |