X-Git-Url: http://git.ozlabs.org/?p=ccan;a=blobdiff_plain;f=ccan%2Ftdb2%2Fopen.c;h=68f707b920ec8cf72bcf66b9788c1abd25bc26c0;hp=21881c350e084dcc5751c395a773ec974662244b;hb=b87e14495d5b07e1b247218a72329f10ecb3da7f;hpb=efdf0f2d8f34b4c01c82c558b350ec36c7329b1e diff --git a/ccan/tdb2/open.c b/ccan/tdb2/open.c index 21881c35..68f707b9 100644 --- a/ccan/tdb2/open.c +++ b/ccan/tdb2/open.c @@ -1,19 +1,38 @@ + /* + Trivial Database 2: opening and closing TDBs + Copyright (C) Rusty Russell 2010 + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 3 of the License, or (at your option) any later version. + + This 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with this library; if not, see . +*/ #include "private.h" +#include +#include -/* all contexts, to ensure no double-opens (fcntl locks don't nest!) */ -static struct tdb_context *tdbs = NULL; +/* all lock info, to detect double-opens (fcntl file don't nest!) */ +static struct tdb_file *files = NULL; -static bool tdb_already_open(dev_t device, ino_t ino) +static struct tdb_file *find_file(dev_t device, ino_t ino) { - struct tdb_context *i; + struct tdb_file *i; - for (i = tdbs; i; i = i->next) { + for (i = files; i; i = i->next) { if (i->device == device && i->inode == ino) { - return true; + i->refcnt++; + break; } } - - return false; + return i; } static bool read_all(int fd, void *buf, size_t len) @@ -100,12 +119,13 @@ static enum TDB_ERROR tdb_new_database(struct tdb_context *tdb, else newdb.hdr.hash_seed = random_number(tdb); newdb.hdr.hash_test = TDB_HASH_MAGIC; - newdb.hdr.hash_test = tdb->khash(&newdb.hdr.hash_test, - sizeof(newdb.hdr.hash_test), - newdb.hdr.hash_seed, - tdb->hash_priv); + newdb.hdr.hash_test = tdb->hash_fn(&newdb.hdr.hash_test, + sizeof(newdb.hdr.hash_test), + newdb.hdr.hash_seed, + tdb->hash_data); newdb.hdr.recovery = 0; newdb.hdr.features_used = newdb.hdr.features_offered = TDB_FEATURE_MASK; + newdb.hdr.seqnum = 0; memset(newdb.hdr.reserved, 0, sizeof(newdb.hdr.reserved)); /* Initial hashes are empty. */ memset(newdb.hdr.hashtable, 0, sizeof(newdb.hdr.hashtable)); @@ -133,29 +153,29 @@ static enum TDB_ERROR tdb_new_database(struct tdb_context *tdb, *hdr = newdb.hdr; if (tdb->flags & TDB_INTERNAL) { - tdb->map_size = sizeof(newdb); - tdb->map_ptr = malloc(tdb->map_size); - if (!tdb->map_ptr) { + tdb->file->map_size = sizeof(newdb); + tdb->file->map_ptr = malloc(tdb->file->map_size); + if (!tdb->file->map_ptr) { return tdb_logerr(tdb, TDB_ERR_OOM, TDB_LOG_ERROR, "tdb_new_database:" " failed to allocate"); } - memcpy(tdb->map_ptr, &newdb, tdb->map_size); + memcpy(tdb->file->map_ptr, &newdb, tdb->file->map_size); return TDB_SUCCESS; } - if (lseek(tdb->fd, 0, SEEK_SET) == -1) { + if (lseek(tdb->file->fd, 0, SEEK_SET) == -1) { return tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR, "tdb_new_database:" " failed to seek: %s", strerror(errno)); } - if (ftruncate(tdb->fd, 0) == -1) { + if (ftruncate(tdb->file->fd, 0) == -1) { return tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR, "tdb_new_database:" " failed to truncate: %s", strerror(errno)); } - rlen = write(tdb->fd, &newdb, sizeof(newdb)); + rlen = write(tdb->file->fd, &newdb, sizeof(newdb)); if (rlen != sizeof(newdb)) { if (rlen >= 0) errno = ENOSPC; @@ -166,6 +186,155 @@ static enum TDB_ERROR tdb_new_database(struct tdb_context *tdb, return TDB_SUCCESS; } +static enum TDB_ERROR tdb_new_file(struct tdb_context *tdb) +{ + tdb->file = malloc(sizeof(*tdb->file)); + if (!tdb->file) + return tdb_logerr(tdb, TDB_ERR_OOM, TDB_LOG_ERROR, + "tdb_open: cannot alloc tdb_file structure"); + tdb->file->num_lockrecs = 0; + tdb->file->lockrecs = NULL; + tdb->file->allrecord_lock.count = 0; + tdb->file->refcnt = 1; + return TDB_SUCCESS; +} + +enum TDB_ERROR tdb_set_attribute(struct tdb_context *tdb, + const union tdb_attribute *attr) +{ + switch (attr->base.attr) { + case TDB_ATTRIBUTE_LOG: + tdb->log_fn = attr->log.fn; + tdb->log_data = attr->log.data; + break; + case TDB_ATTRIBUTE_HASH: + case TDB_ATTRIBUTE_SEED: + case TDB_ATTRIBUTE_OPENHOOK: + return tdb->last_error + = tdb_logerr(tdb, TDB_ERR_EINVAL, + TDB_LOG_USE_ERROR, + "tdb_set_attribute:" + " cannot set %s after opening", + attr->base.attr == TDB_ATTRIBUTE_HASH + ? "TDB_ATTRIBUTE_HASH" + : attr->base.attr == TDB_ATTRIBUTE_SEED + ? "TDB_ATTRIBUTE_SEED" + : "TDB_ATTRIBUTE_OPENHOOK"); + case TDB_ATTRIBUTE_STATS: + return tdb->last_error + = tdb_logerr(tdb, TDB_ERR_EINVAL, + TDB_LOG_USE_ERROR, + "tdb_set_attribute:" + " cannot set TDB_ATTRIBUTE_STATS"); + case TDB_ATTRIBUTE_FLOCK: + tdb->lock_fn = attr->flock.lock; + tdb->unlock_fn = attr->flock.unlock; + tdb->lock_data = attr->flock.data; + break; + default: + return tdb->last_error + = tdb_logerr(tdb, TDB_ERR_EINVAL, + TDB_LOG_USE_ERROR, + "tdb_set_attribute:" + " unknown attribute type %u", + attr->base.attr); + } + return TDB_SUCCESS; +} + +static uint64_t jenkins_hash(const void *key, size_t length, uint64_t seed, + void *unused) +{ + uint64_t ret; + /* hash64_stable assumes lower bits are more important; they are a + * slightly better hash. We use the upper bits first, so swap them. */ + ret = hash64_stable((const unsigned char *)key, length, seed); + return (ret >> 32) | (ret << 32); +} + +enum TDB_ERROR tdb_get_attribute(struct tdb_context *tdb, + union tdb_attribute *attr) +{ + switch (attr->base.attr) { + case TDB_ATTRIBUTE_LOG: + if (!tdb->log_fn) + return tdb->last_error = TDB_ERR_NOEXIST; + attr->log.fn = tdb->log_fn; + attr->log.data = tdb->log_data; + break; + case TDB_ATTRIBUTE_HASH: + attr->hash.fn = tdb->hash_fn; + attr->hash.data = tdb->hash_data; + break; + case TDB_ATTRIBUTE_SEED: + attr->seed.seed = tdb->hash_seed; + break; + case TDB_ATTRIBUTE_OPENHOOK: + return tdb->last_error + = tdb_logerr(tdb, TDB_ERR_EINVAL, + TDB_LOG_USE_ERROR, + "tdb_get_attribute:" + " cannot get TDB_ATTRIBUTE_OPENHOOK"); + case TDB_ATTRIBUTE_STATS: { + size_t size = attr->stats.size; + if (size > tdb->stats.size) + size = tdb->stats.size; + memcpy(&attr->stats, &tdb->stats, size); + break; + } + case TDB_ATTRIBUTE_FLOCK: + attr->flock.lock = tdb->lock_fn; + attr->flock.unlock = tdb->unlock_fn; + attr->flock.data = tdb->lock_data; + break; + default: + return tdb->last_error + = tdb_logerr(tdb, TDB_ERR_EINVAL, + TDB_LOG_USE_ERROR, + "tdb_get_attribute:" + " unknown attribute type %u", + attr->base.attr); + } + attr->base.next = NULL; + return TDB_SUCCESS; +} + +void tdb_unset_attribute(struct tdb_context *tdb, + enum tdb_attribute_type type) +{ + switch (type) { + case TDB_ATTRIBUTE_LOG: + tdb->log_fn = NULL; + break; + case TDB_ATTRIBUTE_HASH: + case TDB_ATTRIBUTE_SEED: + case TDB_ATTRIBUTE_OPENHOOK: + tdb_logerr(tdb, TDB_ERR_EINVAL, TDB_LOG_USE_ERROR, + "tdb_unset_attribute: cannot unset %s after opening", + type == TDB_ATTRIBUTE_HASH + ? "TDB_ATTRIBUTE_HASH" + : type == TDB_ATTRIBUTE_SEED + ? "TDB_ATTRIBUTE_SEED" + : "TDB_ATTRIBUTE_OPENHOOK"); + break; + case TDB_ATTRIBUTE_STATS: + tdb_logerr(tdb, TDB_ERR_EINVAL, + TDB_LOG_USE_ERROR, + "tdb_unset_attribute:" + "cannot unset TDB_ATTRIBUTE_STATS"); + break; + case TDB_ATTRIBUTE_FLOCK: + tdb->lock_fn = tdb_fcntl_lock; + tdb->unlock_fn = tdb_fcntl_unlock; + break; + default: + tdb_logerr(tdb, TDB_ERR_EINVAL, + TDB_LOG_USE_ERROR, + "tdb_unset_attribute: unknown attribute type %u", + type); + } +} + struct tdb_context *tdb_open(const char *name, int tdb_flags, int open_flags, mode_t mode, union tdb_attribute *attr) @@ -178,61 +347,63 @@ struct tdb_context *tdb_open(const char *name, int tdb_flags, ssize_t rlen; struct tdb_header hdr; struct tdb_attribute_seed *seed = NULL; + struct tdb_attribute_openhook *openhook = NULL; tdb_bool_err berr; enum TDB_ERROR ecode; + int openlock; - tdb = malloc(sizeof(*tdb)); + tdb = malloc(sizeof(*tdb) + (name ? strlen(name) + 1 : 0)); if (!tdb) { /* Can't log this */ errno = ENOMEM; return NULL; } - tdb->name = NULL; - tdb->map_ptr = NULL; + /* Set name immediately for logging functions. */ + if (name) { + tdb->name = strcpy((char *)(tdb + 1), name); + } else { + tdb->name = NULL; + } tdb->direct_access = 0; - tdb->fd = -1; - tdb->map_size = sizeof(struct tdb_header); tdb->flags = tdb_flags; - tdb->logfn = NULL; + tdb->log_fn = NULL; tdb->transaction = NULL; - tdb->stats = NULL; tdb->access = NULL; - tdb_hash_init(tdb); + tdb->open_flags = open_flags; + tdb->last_error = TDB_SUCCESS; + tdb->file = NULL; + tdb->lock_fn = tdb_fcntl_lock; + tdb->unlock_fn = tdb_fcntl_unlock; + tdb->hash_fn = jenkins_hash; + memset(&tdb->stats, 0, sizeof(tdb->stats)); + tdb->stats.base.attr = TDB_ATTRIBUTE_STATS; + tdb->stats.size = sizeof(tdb->stats); tdb_io_init(tdb); - tdb_lock_init(tdb); while (attr) { switch (attr->base.attr) { - case TDB_ATTRIBUTE_LOG: - tdb->logfn = attr->log.log_fn; - tdb->log_private = attr->log.log_private; - break; case TDB_ATTRIBUTE_HASH: - tdb->khash = attr->hash.hash_fn; - tdb->hash_priv = attr->hash.hash_private; + tdb->hash_fn = attr->hash.fn; + tdb->hash_data = attr->hash.data; break; case TDB_ATTRIBUTE_SEED: seed = &attr->seed; break; - case TDB_ATTRIBUTE_STATS: - tdb->stats = &attr->stats; - /* They have stats we don't know about? Tell them. */ - if (tdb->stats->size > sizeof(attr->stats)) - tdb->stats->size = sizeof(attr->stats); + case TDB_ATTRIBUTE_OPENHOOK: + openhook = &attr->openhook; break; default: - ecode = tdb_logerr(tdb, TDB_ERR_EINVAL, - TDB_LOG_USE_ERROR, - "tdb_open:" - " unknown attribute type %u", - attr->base.attr); - goto fail; + /* These are set as normal. */ + ecode = tdb_set_attribute(tdb, attr); + if (ecode != TDB_SUCCESS) + goto fail; } attr = attr->base.next; } if (tdb_flags & ~(TDB_INTERNAL | TDB_NOLOCK | TDB_NOMMAP | TDB_CONVERT - | TDB_NOSYNC)) { + | TDB_NOSYNC | TDB_SEQNUM | TDB_ALLOW_NESTING + | TDB_RDONLY)) { ecode = tdb_logerr(tdb, TDB_ERR_EINVAL, TDB_LOG_USE_ERROR, "tdb_open: unknown flags %u", tdb_flags); goto fail; @@ -246,16 +417,27 @@ struct tdb_context *tdb_open(const char *name, int tdb_flags, } if ((open_flags & O_ACCMODE) == O_RDONLY) { - tdb->read_only = true; - tdb->mmap_flags = PROT_READ; + openlock = F_RDLCK; + tdb->flags |= TDB_RDONLY; } else { - tdb->read_only = false; - tdb->mmap_flags = PROT_READ | PROT_WRITE; + if (tdb_flags & TDB_RDONLY) { + ecode = tdb_logerr(tdb, TDB_ERR_EINVAL, + TDB_LOG_USE_ERROR, + "tdb_open: can't use TDB_RDONLY" + " without O_RDONLY"); + goto fail; + } + openlock = F_WRLCK; } /* internal databases don't need any of the rest. */ if (tdb->flags & TDB_INTERNAL) { tdb->flags |= (TDB_NOLOCK | TDB_NOMMAP); + ecode = tdb_new_file(tdb); + if (ecode != TDB_SUCCESS) { + goto fail; + } + tdb->file->fd = -1; ecode = tdb_new_database(tdb, seed, &hdr); if (ecode != TDB_SUCCESS) { goto fail; @@ -266,27 +448,68 @@ struct tdb_context *tdb_open(const char *name, int tdb_flags, return tdb; } - if ((tdb->fd = open(name, open_flags, mode)) == -1) { - /* errno set by open(2) */ - saved_errno = errno; - ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR, + if (stat(name, &st) != -1) + tdb->file = find_file(st.st_dev, st.st_ino); + + if (!tdb->file) { + int fd; + + if ((fd = open(name, open_flags, mode)) == -1) { + /* errno set by open(2) */ + saved_errno = errno; + tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR, "tdb_open: could not open file %s: %s", name, strerror(errno)); - goto fail; - } + goto fail_errno; + } + + /* on exec, don't inherit the fd */ + v = fcntl(fd, F_GETFD, 0); + fcntl(fd, F_SETFD, v | FD_CLOEXEC); + + if (fstat(fd, &st) == -1) { + saved_errno = errno; + tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR, + "tdb_open: could not stat open %s: %s", + name, strerror(errno)); + close(fd); + goto fail_errno; + } - /* on exec, don't inherit the fd */ - v = fcntl(tdb->fd, F_GETFD, 0); - fcntl(tdb->fd, F_SETFD, v | FD_CLOEXEC); + ecode = tdb_new_file(tdb); + if (ecode != TDB_SUCCESS) { + close(fd); + goto fail; + } + + tdb->file->next = files; + tdb->file->fd = fd; + tdb->file->device = st.st_dev; + tdb->file->inode = st.st_ino; + tdb->file->map_ptr = NULL; + tdb->file->map_size = sizeof(struct tdb_header); + } /* ensure there is only one process initialising at once */ - ecode = tdb_lock_open(tdb, TDB_LOCK_WAIT|TDB_LOCK_NOCHECK); + ecode = tdb_lock_open(tdb, openlock, TDB_LOCK_WAIT|TDB_LOCK_NOCHECK); if (ecode != TDB_SUCCESS) { - goto fail; + saved_errno = errno; + goto fail_errno; + } + + /* call their open hook if they gave us one. */ + if (openhook) { + ecode = openhook->fn(tdb->file->fd, openhook->data); + if (ecode != TDB_SUCCESS) { + tdb_logerr(tdb, ecode, TDB_LOG_ERROR, + "tdb_open: open hook failed"); + goto fail; + } + open_flags |= O_CREAT; } /* If they used O_TRUNC, read will return 0. */ - rlen = read(tdb->fd, &hdr, sizeof(hdr)); + rlen = pread(tdb->file->fd, &hdr, sizeof(hdr), 0); if (rlen == 0 && (open_flags & O_CREAT)) { ecode = tdb_new_database(tdb, seed, &hdr); if (ecode != TDB_SUCCESS) { @@ -315,6 +538,12 @@ struct tdb_context *tdb_open(const char *name, int tdb_flags, name, (long long)hdr.version); goto fail; } + } else if (tdb->flags & TDB_CONVERT) { + ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR, + "tdb_open:" + " %s does not need TDB_CONVERT", + name); + goto fail; } tdb_convert(tdb, &hdr, sizeof(hdr)); @@ -330,47 +559,23 @@ struct tdb_context *tdb_open(const char *name, int tdb_flags, goto fail; } - if (fstat(tdb->fd, &st) == -1) { - saved_errno = errno; - ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR, - "tdb_open: could not stat open %s: %s", - name, strerror(errno)); - goto fail; - } - - /* Is it already in the open list? If so, fail. */ - if (tdb_already_open(st.st_dev, st.st_ino)) { - /* FIXME */ - ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_USE_ERROR, - "tdb_open: %s (%d,%d) is already open" - " in this process", - name, (int)st.st_dev, (int)st.st_ino); - goto fail; - } - - tdb->name = strdup(name); - if (!tdb->name) { - ecode = tdb_logerr(tdb, TDB_ERR_OOM, TDB_LOG_ERROR, - "tdb_open: failed to allocate name"); - goto fail; - } - /* Clear any features we don't understand. */ if ((open_flags & O_ACCMODE) != O_RDONLY) { hdr.features_used &= TDB_FEATURE_MASK; - if (tdb_write_convert(tdb, offsetof(struct tdb_header, - features_used), - &hdr.features_used, - sizeof(hdr.features_used)) == -1) + ecode = tdb_write_convert(tdb, offsetof(struct tdb_header, + features_used), + &hdr.features_used, + sizeof(hdr.features_used)); + if (ecode != TDB_SUCCESS) goto fail; } - tdb->device = st.st_dev; - tdb->inode = st.st_ino; - tdb_unlock_open(tdb); + tdb_unlock_open(tdb, openlock); /* This make sure we have current map_size and mmap. */ - tdb->methods->oob(tdb, tdb->map_size + 1, true); + ecode = tdb->methods->oob(tdb, tdb->file->map_size + 1, true); + if (unlikely(ecode != TDB_SUCCESS)) + goto fail; /* Now it's fully formed, recover if necessary. */ berr = tdb_needs_recovery(tdb); @@ -390,49 +595,55 @@ struct tdb_context *tdb_open(const char *name, int tdb_flags, goto fail; } - tdb->next = tdbs; - tdbs = tdb; + /* Add to linked list if we're new. */ + if (tdb->file->refcnt == 1) + files = tdb->file; return tdb; fail: /* Map ecode to some logical errno. */ - if (!saved_errno) { - switch (ecode) { - case TDB_ERR_CORRUPT: - case TDB_ERR_IO: - saved_errno = EIO; - break; - case TDB_ERR_LOCK: - saved_errno = EWOULDBLOCK; - break; - case TDB_ERR_OOM: - saved_errno = ENOMEM; - break; - case TDB_ERR_EINVAL: - saved_errno = EINVAL; - break; - default: - saved_errno = EINVAL; - break; - } - } - + switch (ecode) { + case TDB_ERR_CORRUPT: + case TDB_ERR_IO: + saved_errno = EIO; + break; + case TDB_ERR_LOCK: + saved_errno = EWOULDBLOCK; + break; + case TDB_ERR_OOM: + saved_errno = ENOMEM; + break; + case TDB_ERR_EINVAL: + saved_errno = EINVAL; + break; + default: + saved_errno = EINVAL; + break; + } + +fail_errno: #ifdef TDB_TRACE close(tdb->tracefd); #endif - if (tdb->map_ptr) { - if (tdb->flags & TDB_INTERNAL) { - free(tdb->map_ptr); - } else - tdb_munmap(tdb); - } - free(tdb->lockrecs); - free((char *)tdb->name); - if (tdb->fd != -1) - if (close(tdb->fd) != 0) - tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR, - "tdb_open: failed to close tdb->fd" - " on error: %s", strerror(errno)); + if (tdb->file) { + tdb_lock_cleanup(tdb); + if (--tdb->file->refcnt == 0) { + assert(tdb->file->num_lockrecs == 0); + if (tdb->file->map_ptr) { + if (tdb->flags & TDB_INTERNAL) { + free(tdb->file->map_ptr); + } else + tdb_munmap(tdb->file); + } + if (close(tdb->file->fd) != 0) + tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR, + "tdb_open: failed to close tdb fd" + " on error: %s", strerror(errno)); + free(tdb->file->lockrecs); + free(tdb->file); + } + } + free(tdb); errno = saved_errno; return NULL; @@ -440,7 +651,6 @@ struct tdb_context *tdb_open(const char *name, int tdb_flags, int tdb_close(struct tdb_context *tdb) { - struct tdb_context **i; int ret = 0; tdb_trace(tdb, "tdb_close"); @@ -449,24 +659,28 @@ int tdb_close(struct tdb_context *tdb) tdb_transaction_cancel(tdb); } - if (tdb->map_ptr) { + if (tdb->file->map_ptr) { if (tdb->flags & TDB_INTERNAL) - free(tdb->map_ptr); + free(tdb->file->map_ptr); else - tdb_munmap(tdb); - } - free((char *)tdb->name); - if (tdb->fd != -1) { - ret = close(tdb->fd); - tdb->fd = -1; + tdb_munmap(tdb->file); } - free(tdb->lockrecs); + if (tdb->file) { + struct tdb_file **i; - /* Remove from contexts list */ - for (i = &tdbs; *i; i = &(*i)->next) { - if (*i == tdb) { - *i = tdb->next; - break; + tdb_lock_cleanup(tdb); + if (--tdb->file->refcnt == 0) { + ret = close(tdb->file->fd); + + /* Remove from files list */ + for (i = &files; *i; i = &(*i)->next) { + if (*i == tdb->file) { + *i = tdb->file->next; + break; + } + } + free(tdb->file->lockrecs); + free(tdb->file); } }