]> git.ozlabs.org Git - ccan/blobdiff - ccan/tdb2/tdb.c
tdb2: move open routines into a separate file (open.c)
[ccan] / ccan / tdb2 / tdb.c
index b5e5457691257cbc8034a393f9d2bdeaf091a3cf..02642f58c97427b27a03e9bd8c7bd0c17d087328 100644 (file)
 #include "private.h"
 #include <ccan/asprintf/asprintf.h>
-#include <ccan/tdb2/tdb2.h>
-#include <assert.h>
 #include <stdarg.h>
 
 /* The null return. */
 struct tdb_data tdb_null = { .dptr = NULL, .dsize = 0 };
 
-/* all contexts, to ensure no double-opens (fcntl locks don't nest!) */
-static struct tdb_context *tdbs = NULL;
-
-static bool tdb_already_open(dev_t device, ino_t ino)
-{
-       struct tdb_context *i;
-       
-       for (i = tdbs; i; i = i->next) {
-               if (i->device == device && i->inode == ino) {
-                       return true;
-               }
-       }
-
-       return false;
-}
-
-static bool read_all(int fd, void *buf, size_t len)
-{
-       while (len) {
-               ssize_t ret;
-               ret = read(fd, buf, len);
-               if (ret < 0)
-                       return false;
-               if (ret == 0) {
-                       /* ETOOSHORT? */
-                       errno = EWOULDBLOCK;
-                       return false;
-               }
-               buf = (char *)buf + ret;
-               len -= ret;
-       }
-       return true;
-}
-
-static uint64_t random_number(struct tdb_context *tdb)
-{
-       int fd;
-       uint64_t ret = 0;
-       struct timeval now;
-
-       fd = open("/dev/urandom", O_RDONLY);
-       if (fd >= 0) {
-               if (read_all(fd, &ret, sizeof(ret))) {
-                       close(fd);
-                       return ret;
-               }
-               close(fd);
-       }
-       /* FIXME: Untested!  Based on Wikipedia protocol description! */
-       fd = open("/dev/egd-pool", O_RDWR);
-       if (fd >= 0) {
-               /* Command is 1, next byte is size we want to read. */
-               char cmd[2] = { 1, sizeof(uint64_t) };
-               if (write(fd, cmd, sizeof(cmd)) == sizeof(cmd)) {
-                       char reply[1 + sizeof(uint64_t)];
-                       int r = read(fd, reply, sizeof(reply));
-                       if (r > 1) {
-                               /* Copy at least some bytes. */
-                               memcpy(&ret, reply+1, r - 1);
-                               if (reply[0] == sizeof(uint64_t)
-                                   && r == sizeof(reply)) {
-                                       close(fd);
-                                       return ret;
-                               }
-                       }
-               }
-               close(fd);
-       }
-
-       /* Fallback: pid and time. */
-       gettimeofday(&now, NULL);
-       ret = getpid() * 100132289ULL + now.tv_sec * 1000000ULL + now.tv_usec;
-       tdb_logerr(tdb, TDB_SUCCESS, TDB_LOG_WARNING,
-                  "tdb_open: random from getpid and time");
-       return ret;
-}
-
-struct new_database {
-       struct tdb_header hdr;
-       struct tdb_freetable ftable;
-};
-
-/* initialise a new database */
-static enum TDB_ERROR tdb_new_database(struct tdb_context *tdb,
-                                      struct tdb_attribute_seed *seed,
-                                      struct tdb_header *hdr)
-{
-       /* We make it up in memory, then write it out if not internal */
-       struct new_database newdb;
-       unsigned int magic_len;
-       ssize_t rlen;
-       enum TDB_ERROR ecode;
-
-       /* Fill in the header */
-       newdb.hdr.version = TDB_VERSION;
-       if (seed)
-               newdb.hdr.hash_seed = seed->seed;
-       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.recovery = 0;
-       newdb.hdr.features_used = newdb.hdr.features_offered = TDB_FEATURE_MASK;
-       memset(newdb.hdr.reserved, 0, sizeof(newdb.hdr.reserved));
-       /* Initial hashes are empty. */
-       memset(newdb.hdr.hashtable, 0, sizeof(newdb.hdr.hashtable));
-
-       /* Free is empty. */
-       newdb.hdr.free_table = offsetof(struct new_database, ftable);
-       memset(&newdb.ftable, 0, sizeof(newdb.ftable));
-       ecode = set_header(NULL, &newdb.ftable.hdr, TDB_FTABLE_MAGIC, 0,
-                          sizeof(newdb.ftable) - sizeof(newdb.ftable.hdr),
-                          sizeof(newdb.ftable) - sizeof(newdb.ftable.hdr),
-                          0);
-       if (ecode != TDB_SUCCESS) {
-               return ecode;
-       }
-
-       /* Magic food */
-       memset(newdb.hdr.magic_food, 0, sizeof(newdb.hdr.magic_food));
-       strcpy(newdb.hdr.magic_food, TDB_MAGIC_FOOD);
-
-       /* This creates an endian-converted database, as if read from disk */
-       magic_len = sizeof(newdb.hdr.magic_food);
-       tdb_convert(tdb,
-                   (char *)&newdb.hdr + magic_len, sizeof(newdb) - magic_len);
-
-       *hdr = newdb.hdr;
-
-       if (tdb->flags & TDB_INTERNAL) {
-               tdb->map_size = sizeof(newdb);
-               tdb->map_ptr = malloc(tdb->map_size);
-               if (!tdb->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);
-               return TDB_SUCCESS;
-       }
-       if (lseek(tdb->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) {
-               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));
-       if (rlen != sizeof(newdb)) {
-               if (rlen >= 0)
-                       errno = ENOSPC;
-               return tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
-                                 "tdb_new_database: %zi writing header: %s",
-                                 rlen, strerror(errno));
-       }
-       return TDB_SUCCESS;
-}
-
-struct tdb_context *tdb_open(const char *name, int tdb_flags,
-                            int open_flags, mode_t mode,
-                            union tdb_attribute *attr)
-{
-       struct tdb_context *tdb;
-       struct stat st;
-       int saved_errno = 0;
-       uint64_t hash_test;
-       unsigned v;
-       ssize_t rlen;
-       struct tdb_header hdr;
-       struct tdb_attribute_seed *seed = NULL;
-       tdb_bool_err berr;
-       enum TDB_ERROR ecode;
-
-       tdb = malloc(sizeof(*tdb));
-       if (!tdb) {
-               /* Can't log this */
-               errno = ENOMEM;
-               return NULL;
-       }
-       tdb->name = NULL;
-       tdb->map_ptr = NULL;
-       tdb->direct_access = 0;
-       tdb->fd = -1;
-       tdb->map_size = sizeof(struct tdb_header);
-       tdb->flags = tdb_flags;
-       tdb->logfn = NULL;
-       tdb->transaction = NULL;
-       tdb->stats = NULL;
-       tdb->access = NULL;
-       tdb_hash_init(tdb);
-       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;
-                       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);
-                       break;
-               default:
-                       ecode = tdb_logerr(tdb, TDB_ERR_EINVAL,
-                                          TDB_LOG_USE_ERROR,
-                                          "tdb_open:"
-                                          " unknown attribute type %u",
-                                          attr->base.attr);
-                       goto fail;
-               }
-               attr = attr->base.next;
-       }
-
-       if (tdb_flags & ~(TDB_INTERNAL | TDB_NOLOCK | TDB_NOMMAP | TDB_CONVERT
-                         | TDB_NOSYNC)) {
-               ecode = tdb_logerr(tdb, TDB_ERR_EINVAL, TDB_LOG_USE_ERROR,
-                                  "tdb_open: unknown flags %u", tdb_flags);
-               goto fail;
-       }
-
-       if ((open_flags & O_ACCMODE) == O_WRONLY) {
-               ecode = tdb_logerr(tdb, TDB_ERR_EINVAL, TDB_LOG_USE_ERROR,
-                                  "tdb_open: can't open tdb %s write-only",
-                                  name);
-               goto fail;
-       }
-
-       if ((open_flags & O_ACCMODE) == O_RDONLY) {
-               tdb->read_only = true;
-               tdb->mmap_flags = PROT_READ;
-       } else {
-               tdb->read_only = false;
-               tdb->mmap_flags = PROT_READ | PROT_WRITE;
-       }
-
-       /* internal databases don't need any of the rest. */
-       if (tdb->flags & TDB_INTERNAL) {
-               tdb->flags |= (TDB_NOLOCK | TDB_NOMMAP);
-               ecode = tdb_new_database(tdb, seed, &hdr);
-               if (ecode != TDB_SUCCESS) {
-                       goto fail;
-               }
-               tdb_convert(tdb, &hdr.hash_seed, sizeof(hdr.hash_seed));
-               tdb->hash_seed = hdr.hash_seed;
-               tdb_ftable_init(tdb);
-               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,
-                                  "tdb_open: could not open file %s: %s",
-                                  name, strerror(errno));
-               goto fail;
-       }
-
-       /* on exec, don't inherit the fd */
-       v = fcntl(tdb->fd, F_GETFD, 0);
-        fcntl(tdb->fd, F_SETFD, v | FD_CLOEXEC);
-
-       /* ensure there is only one process initialising at once */
-       ecode = tdb_lock_open(tdb, TDB_LOCK_WAIT|TDB_LOCK_NOCHECK);
-       if (ecode != TDB_SUCCESS) {
-               goto fail;
-       }
-
-       /* If they used O_TRUNC, read will return 0. */
-       rlen = read(tdb->fd, &hdr, sizeof(hdr));
-       if (rlen == 0 && (open_flags & O_CREAT)) {
-               ecode = tdb_new_database(tdb, seed, &hdr);
-               if (ecode != TDB_SUCCESS) {
-                       goto fail;
-               }
-       } else if (rlen < 0) {
-               ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
-                                  "tdb_open: error %s reading %s",
-                                  strerror(errno), name);
-               goto fail;
-       } else if (rlen < sizeof(hdr)
-                  || strcmp(hdr.magic_food, TDB_MAGIC_FOOD) != 0) {
-               ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
-                                  "tdb_open: %s is not a tdb file", name);
-               goto fail;
-       }
-
-       if (hdr.version != TDB_VERSION) {
-               if (hdr.version == bswap_64(TDB_VERSION))
-                       tdb->flags |= TDB_CONVERT;
-               else {
-                       /* wrong version */
-                       ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
-                                          "tdb_open:"
-                                          " %s is unknown version 0x%llx",
-                                          name, (long long)hdr.version);
-                       goto fail;
-               }
-       }
-
-       tdb_convert(tdb, &hdr, sizeof(hdr));
-       tdb->hash_seed = hdr.hash_seed;
-       hash_test = TDB_HASH_MAGIC;
-       hash_test = tdb_hash(tdb, &hash_test, sizeof(hash_test));
-       if (hdr.hash_test != hash_test) {
-               /* wrong hash variant */
-               ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
-                                  "tdb_open:"
-                                  " %s uses a different hash function",
-                                  name);
-               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)
-                       goto fail;
-       }
-
-       tdb->device = st.st_dev;
-       tdb->inode = st.st_ino;
-       tdb_unlock_open(tdb);
-
-       /* This make sure we have current map_size and mmap. */
-       tdb->methods->oob(tdb, tdb->map_size + 1, true);
-
-       /* Now it's fully formed, recover if necessary. */
-       berr = tdb_needs_recovery(tdb);
-       if (unlikely(berr != false)) {
-               if (berr < 0) {
-                       ecode = berr;
-                       goto fail;
-               }
-               ecode = tdb_lock_and_recover(tdb);
-               if (ecode != TDB_SUCCESS) {
-                       goto fail;
-               }
-       }
-
-       ecode = tdb_ftable_init(tdb);
-       if (ecode != TDB_SUCCESS) {
-               goto fail;
-       }
-
-       tdb->next = tdbs;
-       tdbs = tdb;
-       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;
-               }
-       }
-
-#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));
-       free(tdb);
-       errno = saved_errno;
-       return NULL;
-}
-
 static enum TDB_ERROR update_rec_hdr(struct tdb_context *tdb,
                                     tdb_off_t off,
                                     tdb_len_t keylen,
@@ -718,46 +278,6 @@ unlock:
        return ecode;
 }
 
-int tdb_close(struct tdb_context *tdb)
-{
-       struct tdb_context **i;
-       int ret = 0;
-
-       tdb_trace(tdb, "tdb_close");
-
-       if (tdb->transaction) {
-               tdb_transaction_cancel(tdb);
-       }
-
-       if (tdb->map_ptr) {
-               if (tdb->flags & TDB_INTERNAL)
-                       free(tdb->map_ptr);
-               else
-                       tdb_munmap(tdb);
-       }
-       free((char *)tdb->name);
-       if (tdb->fd != -1) {
-               ret = close(tdb->fd);
-               tdb->fd = -1;
-       }
-       free(tdb->lockrecs);
-
-       /* Remove from contexts list */
-       for (i = &tdbs; *i; i = &(*i)->next) {
-               if (*i == tdb) {
-                       *i = tdb->next;
-                       break;
-               }
-       }
-
-#ifdef TDB_TRACE
-       close(tdb->tracefd);
-#endif
-       free(tdb);
-
-       return ret;
-}
-
 unsigned int tdb_get_flags(struct tdb_context *tdb)
 {
        return tdb->flags;