X-Git-Url: http://git.indexdata.com/?a=blobdiff_plain;f=util%2Fgw-db.c;h=dd3b2c12c1a1555ce40fd2d92404d82f9c1150cc;hb=67ac07cdd6c04dd152397a25dd583ea4cb9ea331;hp=97bb3065d91343d4f041f34d2bfce90a9b149d41;hpb=566b5cccc9ee5bfe515a452cbed95fec34bfd074;p=egate.git

diff --git a/util/gw-db.c b/util/gw-db.c
index 97bb306..dd3b2c1 100644
--- a/util/gw-db.c
+++ b/util/gw-db.c
@@ -45,7 +45,12 @@
  * Europagate, 1995
  *
  * $Log: gw-db.c,v $
- * Revision 1.3  1995/05/16 09:40:53  adam
+ * Revision 1.4  1995/12/20 16:28:07  adam
+ * Extra parameter block to gw_db_open. If block is 0 gw_db_open
+ * returns NULL if lock couldn't be satisfied.
+ * Minor changes in iso2709.c.
+ *
+ * Revision 1.3  1995/05/16  09:40:53  adam
  * LICENSE.
  *
  * Revision 1.2  1995/05/01  12:43:57  adam
@@ -64,6 +69,7 @@
 #include <unistd.h>
 #include <fcntl.h>
 
+#include <gw-log.h>
 #include <gw-db.h>
 
 #define FILE_HEAD_LEN 128
@@ -87,6 +93,8 @@ struct db_bucket {         /* information about individual entries */
     int  prev;             /* prev in hach chain - possibly 0 */
 };
 
+static char *mod = "gwdb";
+
 /*
  * write_head: write header of table
  */
@@ -122,16 +130,17 @@ static unsigned hash (const char *name, int length)
 /*
  * lock_file: lock entire file 
  */
-static void lock_file (int fd, int type)
+static int lock_file (int fd, int block, int type)
 {
     struct flock area;
     area.l_type = type;
     area.l_whence = SEEK_SET;
     area.l_start = 0L;
     area.l_len = 0L;
-    fcntl (fd, F_SETLKW, &area);
+    return fcntl (fd, block ? F_SETLKW : F_SETLK, &area);
 }
 
+
 /*
  * gw_db_lookup: table lookup
  */
@@ -287,24 +296,52 @@ static GW_DB gw_db_free (GW_DB db)
 /*
  * gw_db_open: open and lock table for reading (and writing)
  */
-GW_DB gw_db_open (const char *fname, int write_flag)
+GW_DB gw_db_open (const char *fname, int write_flag, int block)
 {
     char file_head_buf[FILE_HEAD_LEN];
     GW_DB db;
     int r;
 
-    if (!(db = malloc (sizeof(*db))))
-        return NULL;
+    db = malloc (sizeof(*db));
+    if (!db)
+    {
+        gw_log (GW_LOG_FATAL|GW_LOG_ERRNO, mod, "malloc");
+        exit (1);
+    }
     db->dirty = 0;
     if (!(db->hash_array = malloc (DB_HASH * sizeof(*db->hash_array))))
-        return gw_db_free (db);
+    {
+        gw_log (GW_LOG_FATAL|GW_LOG_ERRNO, mod, "malloc");
+        exit (1);
+    }
     if (write_flag)
-        db->fd = open (fname, O_RDWR|O_CREAT, 0666);
+    {
+        if ((db->fd = open (fname, O_RDWR|O_CREAT, 0666)) == -1)
+        {
+            gw_log (GW_LOG_FATAL|GW_LOG_ERRNO, mod, "open %s", fname);
+            exit (1);
+        }
+    }
     else
-        db->fd = open (fname, O_RDONLY);
-    if (db->fd == -1)
-        return gw_db_free (db);
-    lock_file (db->fd, write_flag ? F_WRLCK : F_RDLCK);
+    {
+        if ((db->fd = open (fname, O_RDONLY)) == -1)
+        {
+            gw_log (GW_LOG_WARN|GW_LOG_ERRNO," open %s", fname);
+            return gw_db_free (db);
+        }
+    }
+    if (block)
+        lock_file (db->fd, 1, write_flag ? F_WRLCK : F_RDLCK);
+    else
+    {
+        r = lock_file (db->fd, 0, write_flag ? F_WRLCK : F_RDLCK);
+        if (r == -1)
+        {
+            gw_log (GW_LOG_WARN|GW_LOG_ERRNO, "flock %s", fname);
+            close (db->fd);
+            return gw_db_free (db);
+        }
+    }
     r = read (db->fd, file_head_buf, FILE_HEAD_LEN);
     if (r == -1)
         return gw_db_free (db);
@@ -340,7 +377,7 @@ int gw_db_close (GW_DB db)
 
     if (db->dirty) 
         r = write_head (db);
-    lock_file (db->fd, F_UNLCK);
+    lock_file (db->fd, 1, F_UNLCK);
     if (close (db->fd) == -1)
     {
         gw_db_free (db);