cscvs to tla changeset 55

Author: noodles
Date: 2003/02/02 23:59:15
Try to break deadlocks when we start and react better to being told we're in a
deadlock.

diff --git a/keydb_db3.c b/keydb_db3.c
index 0ccaec33d63857fe0fdf9bc0320ef89078bf3550..4d1bcca162acc14948e0e0e29be077170d76c2fb 100644 (file)
--- a/keydb_db3.c
+++ b/keydb_db3.c
@@ -116,10 +116,21 @@ void initdb(void)
                exit(1);
        }
 
+       /*
+        * This is a bit of a kludge. Either we run a separate process for
+        * deadlock detection or we do this every time we run. What we really
+        * want to do is specify that our locks are exclusive locks when we
+        * start to do an update.
+        */
+       ret = lock_detect(dbenv,
+                       0, /* flags */
+                       DB_LOCK_RANDOM,
+                       NULL); /* If non null int* for number broken */
+
        ret = dbenv->open(dbenv, config.db_dir,
                        DB_INIT_LOG | DB_INIT_MPOOL | DB_INIT_LOCK |
                        DB_INIT_TXN |
-                       DB_RECOVER | DB_CREATE,
+                       DB_CREATE,
                        0);
        if (ret != 0) {
                dbenv->err(dbenv, ret, "%s", config.db_dir);
@@ -424,6 +435,7 @@ int store_key(struct openpgp_publickey *publickey, bool intrans, bool update)
        unsigned char worddb_data[12];
        struct ll *wordlist = NULL;
        struct ll *curword  = NULL;
+       bool       deadlock = false;
 
        keyid = get_keyid(publickey);
 
@@ -440,61 +452,69 @@ int store_key(struct openpgp_publickey *publickey, bool intrans, bool update)
         * it definitely needs updated.
         */
        if (update) {
-               delete_key(keyid, true);
+               deadlock = (delete_key(keyid, true) == -1);
        }
 
        /*
         * Convert the key to a flat set of binary data.
         */
-       next = publickey->next;
-       publickey->next = NULL;
-       flatten_publickey(publickey, &packets, &list_end);
-       publickey->next = next;
-
-       storebuf.offset = 0; 
-       storebuf.size = 8192;
-       storebuf.buffer = malloc(8192);
+       if (!deadlock) {
+               next = publickey->next;
+               publickey->next = NULL;
+               flatten_publickey(publickey, &packets, &list_end);
+               publickey->next = next;
+
+               storebuf.offset = 0; 
+               storebuf.size = 8192;
+               storebuf.buffer = malloc(8192);
        
-       write_openpgp_stream(buffer_putchar, &storebuf, packets);
+               write_openpgp_stream(buffer_putchar, &storebuf, packets);
 
-       /*
-        * Now we have the key data store it in the DB; the keyid is the key.
-        */
-       memset(&key, 0, sizeof(key));
-       memset(&data, 0, sizeof(data));
-       key.data = &keyid;
-       key.size = sizeof(keyid);
-       keyid &= 0xFFFFFFFF;
-       data.size = storebuf.offset;
-       data.data = storebuf.buffer;
-
-       ret = dbconn->put(dbconn,
-                       txn,
-                       &key,
-                       &data,
-                       0); /* flags*/
-       if (ret != 0) {
-               dbconn->err(dbconn, ret, "Problem storing key");
-       }
+               /*
+                * Now we have the key data store it in the DB; the keyid is
+                * the key.
+                */
+               memset(&key, 0, sizeof(key));
+               memset(&data, 0, sizeof(data));
+               key.data = &keyid;
+               key.size = sizeof(keyid);
+               keyid &= 0xFFFFFFFF;
+               data.size = storebuf.offset;
+               data.data = storebuf.buffer;
 
-       free(storebuf.buffer);
-       storebuf.buffer = NULL;
-       storebuf.size = 0;
-       storebuf.offset = 0; 
+               ret = dbconn->put(dbconn,
+                               txn,
+                               &key,
+                               &data,
+                               0); /* flags*/
+               if (ret != 0) {
+                       dbconn->err(dbconn, ret, "Problem storing key");
+                       if (ret == DB_LOCK_DEADLOCK) {
+                               deadlock = true;
+                       }
+               }
 
-       free_packet_list(packets);
-       packets = NULL;
+               free(storebuf.buffer);
+               storebuf.buffer = NULL;
+               storebuf.size = 0;
+               storebuf.offset = 0; 
+       
+               free_packet_list(packets);
+               packets = NULL;
+       }
 
        /*
         * Walk through our uids storing the words into the db with the keyid.
         */
-       uids = keyuids(publickey, &primary);
+       if (!deadlock) {
+               uids = keyuids(publickey, &primary);
+       }
        if (uids != NULL) {
                for (i = 0; ret == 0 && uids[i] != NULL; i++) {
                        wordlist = makewordlist(wordlist, uids[i]);
                }
 
-               for (curword = wordlist; curword != NULL;
+               for (curword = wordlist; curword != NULL && !deadlock;
                                curword = curword->next) {
                        memset(&key, 0, sizeof(key));
                        memset(&data, 0, sizeof(data));
@@ -527,6 +547,9 @@ int store_key(struct openpgp_publickey *publickey, bool intrans, bool update)
                        if (ret != 0) {
                                worddb->err(worddb, ret,
                                        "Problem storing key");
+                               if (ret == DB_LOCK_DEADLOCK) {
+                                       deadlock = true;
+                               }
                        }
                }
 
@@ -546,7 +569,7 @@ int store_key(struct openpgp_publickey *publickey, bool intrans, bool update)
                endtrans();
        }
 
-       return 0;
+       return deadlock ? -1 : 0 ;
 }
 
 /**
@@ -569,6 +592,7 @@ int delete_key(uint64_t keyid, bool intrans)
        unsigned char worddb_data[12];
        struct ll *wordlist = NULL;
        struct ll *curword  = NULL;
+       bool deadlock = false;
 
        keyid &= 0xFFFFFFFF;
 
@@ -594,7 +618,7 @@ int delete_key(uint64_t keyid, bool intrans)
                        &cursor,
                        0);   /* flags */
 
-               for (curword = wordlist; curword != NULL;
+               for (curword = wordlist; curword != NULL && !deadlock;
                                curword = curword->next) {
                        memset(&key, 0, sizeof(key));
                        memset(&data, 0, sizeof(data));
@@ -636,6 +660,9 @@ int delete_key(uint64_t keyid, bool intrans)
                        if (ret != 0) {
                                worddb->err(worddb, ret,
                                        "Problem deleting word.");
+                               if (ret == DB_LOCK_DEADLOCK) {
+                                       deadlock = true;
+                               }
                        }
                }
                ret = cursor->c_close(cursor);
@@ -655,19 +682,21 @@ int delete_key(uint64_t keyid, bool intrans)
                publickey = NULL;
        }
 
-       key.data = &keyid;
-       key.size = sizeof(keyid);
+       if (!deadlock) {
+               key.data = &keyid;
+               key.size = sizeof(keyid);
 
-       dbconn->del(dbconn,
-                       txn,
-                       &key,
-                       0); /* flags */
+               dbconn->del(dbconn,
+                               txn,
+                               &key,
+                               0); /* flags */
+       }
 
        if (!intrans) {
                endtrans();
        }
 
-       return (ret == DB_NOTFOUND);
+       return deadlock ? (-1) : (ret == DB_NOTFOUND);
 }
 
 /*