diff options
Diffstat (limited to 'source/tdb/tdb.c')
-rw-r--r-- | source/tdb/tdb.c | 35 |
1 files changed, 33 insertions, 2 deletions
diff --git a/source/tdb/tdb.c b/source/tdb/tdb.c index ed75a55e3e9..c57d23cb6f5 100644 --- a/source/tdb/tdb.c +++ b/source/tdb/tdb.c @@ -34,6 +34,7 @@ #include <errno.h> #include <sys/mman.h> #include <sys/stat.h> +#include <signal.h> #include "tdb.h" #include "spinlock.h" #else @@ -160,6 +161,18 @@ struct list_struct { */ }; +/*************************************************************** + Allow a caller to set a "alarm" flag that tdb can check to abort + a blocking lock on SIGALRM. +***************************************************************/ + +static sig_atomic_t *palarm_fired; + +void tdb_set_lock_alarm(sig_atomic_t *palarm) +{ + palarm_fired = palarm; +} + /* a byte range locking function - return 0 on success this functions locks/unlocks 1 byte at the specified offset. @@ -186,6 +199,8 @@ static int tdb_brlock(TDB_CONTEXT *tdb, tdb_off offset, do { ret = fcntl(tdb->fd,lck_type,&fl); + if (ret == -1 && errno == EINTR && palarm_fired && *palarm_fired) + break; } while (ret == -1 && errno == EINTR); if (ret == -1) { @@ -193,6 +208,10 @@ static int tdb_brlock(TDB_CONTEXT *tdb, tdb_off offset, TDB_LOG((tdb, 5,"tdb_brlock failed (fd=%d) at offset %d rw_type=%d lck_type=%d\n", tdb->fd, offset, rw_type, lck_type)); } + /* Was it an alarm timeout ? */ + if (errno == EINTR && palarm_fired && *palarm_fired) + return TDB_ERRCODE(TDB_ERR_LOCK_TIMEOUT, -1); + /* Otherwise - generic lock error. */ /* errno set by fcntl */ return TDB_ERRCODE(TDB_ERR_LOCK, -1); } @@ -517,17 +536,20 @@ int tdb_printfreelist(TDB_CONTEXT *tdb) /* read in the freelist top */ if (ofs_read(tdb, offset, &rec_ptr) == -1) { + tdb_unlock(tdb, -1, F_WRLCK); return 0; } printf("freelist top=[0x%08x]\n", rec_ptr ); while (rec_ptr) { if (tdb_read(tdb, rec_ptr, (char *)&rec, sizeof(rec), DOCONV()) == -1) { + tdb_unlock(tdb, -1, F_WRLCK); return -1; } if (rec.magic != TDB_FREE_MAGIC) { printf("bad magic 0x%08x in free list\n", rec.magic); + tdb_unlock(tdb, -1, F_WRLCK); return -1; } @@ -1030,6 +1052,12 @@ static int tdb_update(TDB_CONTEXT *tdb, TDB_DATA key, TDB_DATA dbuf) } /* find an entry in the database given a key */ +/* If an entry doesn't exist tdb_err will be set to + * TDB_ERR_NOEXIST. If a key has no data attached + * tdb_err will not be set. Both will return a + * zero pptr and zero dsize. + */ + TDB_DATA tdb_fetch(TDB_CONTEXT *tdb, TDB_DATA key) { tdb_off rec_ptr; @@ -1040,8 +1068,11 @@ TDB_DATA tdb_fetch(TDB_CONTEXT *tdb, TDB_DATA key) if (!(rec_ptr = tdb_find_lock(tdb,key,F_RDLCK,&rec))) return tdb_null; - ret.dptr = tdb_alloc_read(tdb, rec_ptr + sizeof(rec) + rec.key_len, - rec.data_len); + if (rec.data_len) + ret.dptr = tdb_alloc_read(tdb, rec_ptr + sizeof(rec) + rec.key_len, + rec.data_len); + else + ret.dptr = NULL; ret.dsize = rec.data_len; tdb_unlock(tdb, BUCKET(rec.full_hash), F_RDLCK); return ret; |