diff options
Diffstat (limited to 'source3')
| -rw-r--r-- | source3/printing/printing.c | 79 |
1 files changed, 61 insertions, 18 deletions
diff --git a/source3/printing/printing.c b/source3/printing/printing.c index cb689c05d6..61c3282196 100644 --- a/source3/printing/printing.c +++ b/source3/printing/printing.c @@ -132,11 +132,13 @@ static pid_t local_pid; static int get_queue_status(int, print_status_struct *); +/* There can be this many printing tdb's open, plus any locked ones. */ #define MAX_PRINT_DBS_OPEN 1 struct tdb_print_db { struct tdb_print_db *next, *prev; TDB_CONTEXT *tdb; + int locked; fstring printer_name; }; @@ -149,7 +151,7 @@ static struct tdb_print_db *print_db_head; static struct tdb_print_db *get_print_db_byname(const char *printername) { - struct tdb_print_db *p, *last_entry; + struct tdb_print_db *p = NULL, *last_entry = NULL; int num_open = 0; pstring printdb_path; @@ -161,20 +163,28 @@ static struct tdb_print_db *get_print_db_byname(const char *printername) num_open++; last_entry = p; } + /* Not found. */ if (num_open >= MAX_PRINT_DBS_OPEN) { - /* Recycle the last entry. */ + /* Try and recycle the last entry. */ DLIST_PROMOTE(print_db_head, last_entry); - if (print_db_head->tdb) { - if (tdb_close(print_db_head->tdb)) { - DEBUG(0,("get_print_db: Failed to close tdb for printer %s\n", - print_db_head->printer_name )); - return NULL; + + for (p = print_db_head; p; p = p->next) { + if (p->locked) + continue; + if (p->tdb) { + if (tdb_close(print_db_head->tdb)) { + DEBUG(0,("get_print_db: Failed to close tdb for printer %s\n", + print_db_head->printer_name )); + return NULL; + } + ZERO_STRUCTP(p); + DLIST_PROMOTE(print_db_head, p); } } - p = print_db_head; - ZERO_STRUCTP(p); - } else { + } + + if (!p) { /* Create one. */ p = (struct tdb_print_db *)malloc(sizeof(struct tdb_print_db)); if (!p) { @@ -205,6 +215,30 @@ static struct tdb_print_db *get_print_db_byname(const char *printername) } /**************************************************************************** + Lock a pdb entry by string. +****************************************************************************/ + +static int pdb_entry_lock(struct tdb_print_db *pdb, char *key) +{ + if (pdb->locked == 0) { + if (tdb_lock_bystring(pdb->tdb, key) == -1) + return -1; + } + pdb->locked++; +} + +/**************************************************************************** + Unlock a pdb entry by string. +****************************************************************************/ + +static void pdb_entry_unlock(struct tdb_print_db *pdb, char *key) +{ + pdb->locked--; + if (pdb->locked == 0) + tdb_unlock_bystring(pdb->tdb, key); +} + +/**************************************************************************** Initialise the printing backend. Called once at startup. Does not survive a fork ****************************************************************************/ @@ -235,12 +269,15 @@ BOOL print_backend_init(void) pdb = get_print_db_byname(lp_const_servicename(snum)); if (!pdb) continue; - tdb_lock_bystring(pdb->tdb, sversion); + if (pdb_entry_lock(pdb, sversion) == -1) { + DEBUG(0,("print_backend_init: Failed to open printer %s database\n", lp_const_servicename(snum) )); + return False; + } if (tdb_fetch_int32(pdb->tdb, sversion) != PRINT_DATABASE_VERSION) { tdb_traverse(pdb->tdb, tdb_traverse_delete_fn, NULL); tdb_store_int32(pdb->tdb, sversion, PRINT_DATABASE_VERSION); } - tdb_unlock_bystring(pdb->tdb, sversion); + pdb_entry_unlock(pdb, sversion); } /* select the appropriate printing interface... */ @@ -746,7 +783,10 @@ static void print_queue_update(int snum) /* Lock the queue for the database update */ slprintf(keystr, sizeof(keystr) - 1, "LOCK/%s", printer_name); - tdb_lock_bystring(pdb->tdb, keystr); + if (pdb_entry_lock(pdb, keystr) == -1) { + DEBUG(0,("print_queue_update: Failed to lock printer %s database\n", printer_name)); + return; + } /* * Ensure that no one else got in here. @@ -758,7 +798,7 @@ static void print_queue_update(int snum) /* * Someone else is doing the update, exit. */ - tdb_unlock_bystring(pdb->tdb, keystr); + pdb_entry_unlock(pdb, keystr); return; } @@ -774,7 +814,7 @@ static void print_queue_update(int snum) * the update. */ - tdb_unlock_bystring(pdb->tdb, keystr); + pdb_entry_unlock(pdb, keystr); /* * Update the cache time FIRST ! Stops others even @@ -1335,7 +1375,10 @@ uint32 print_job_start(struct current_user *user, int snum, char *jobname) fstrcpy(pjob.queuename, lp_const_servicename(snum)); /* lock the database */ - tdb_lock_bystring(pdb->tdb, "INFO/nextjob"); + if (pdb_entry_lock(pdb, "INFO/nextjob") == -1) { + DEBUG(0,("print_job_start: failed to lock printing database %s\n", printername )); + return (uint32)-1; + } next_jobid = tdb_fetch_int32(pdb->tdb, "INFO/nextjob"); if (next_jobid == -1) @@ -1378,7 +1421,7 @@ to open spool file %s.\n", pjob.filename)); pjob_store(snum, jobid, &pjob); - tdb_unlock_bystring(pdb->tdb, "INFO/nextjob"); + pdb_entry_unlock(pdb, "INFO/nextjob"); /* * If the printer is marked as postscript output a leading @@ -1397,7 +1440,7 @@ to open spool file %s.\n", pjob.filename)); if (jobid != -1) pjob_delete(snum, jobid); - tdb_unlock_bystring(pdb->tdb, "INFO/nextjob"); + pdb_entry_unlock(pdb, "INFO/nextjob"); DEBUG(3, ("print_job_start: returning fail. Error = %s\n", strerror(errno) )); return -1; |