[Fix] Fix locking in mmapped statistics

diff --git a/src/libstat/backends/mmaped_file.c b/src/libstat/backends/mmaped_file.c
index a2d81944e7f974a28ca2a5f6f18504fb45be0354..6ebe904e4280fcc9ccf07a921959af1841f843af 100644 (file)
--- a/src/libstat/backends/mmaped_file.c
+++ b/src/libstat/backends/mmaped_file.c
@@ -400,6 +400,10 @@ rspamd_mmaped_file_reindex (rspamd_mempool_t *pool,
        u_char *map, *pos;
        struct stat_file_block *block;
        struct stat_file_header *header, *nh;
+       struct timespec sleep_ts = {
+                       .tv_sec = 0,
+                       .tv_nsec = 1000000
+       };
 
        if (size <
                sizeof (struct stat_file_header) + sizeof (struct stat_file_section) +
@@ -415,28 +419,19 @@ rspamd_mmaped_file_reindex (rspamd_mempool_t *pool,
 
        if (lock_fd == -1) {
                /* Wait for lock */
-               lock_fd = open (lock, O_RDONLY, 00600);
+               lock_fd = open (lock, O_WRONLY|O_CREAT|O_EXCL, 00600);
                if (lock_fd != -1) {
-                       if (!rspamd_file_lock (lock_fd, TRUE)) {
-                               close (lock_fd);
-                               g_free (lock);
+                       unlink (lock);
+                       close (lock_fd);
+                       g_free (lock);
 
-                               return rspamd_mmaped_file_open (pool, filename, size, stcf);
-                       }
+                       return rspamd_mmaped_file_open (pool, filename, size, stcf);
                }
                else {
-                       return rspamd_mmaped_file_open (pool, filename, size, stcf);
+                       nanosleep (&sleep_ts, NULL);
                }
        }
 
-       if (!rspamd_file_lock (lock_fd, TRUE)) {
-               close (lock_fd);
-               unlink (lock);
-               g_free (lock);
-
-               return rspamd_mmaped_file_open (pool, filename, size, stcf);
-       }
-
        old = rspamd_mmaped_file_open (pool, filename, old_size, stcf);
 
        if (old == NULL) {
@@ -451,7 +446,6 @@ rspamd_mmaped_file_reindex (rspamd_mempool_t *pool,
                g_free (backup);
                unlink (lock);
                g_free (lock);
-               rspamd_file_unlock (lock_fd, FALSE);
                close (lock_fd);
 
                return NULL;
@@ -463,7 +457,6 @@ rspamd_mmaped_file_reindex (rspamd_mempool_t *pool,
                g_free (backup);
                unlink (lock);
                g_free (lock);
-               rspamd_file_unlock (lock_fd, FALSE);
                close (lock_fd);
 
                return NULL;
@@ -482,7 +475,6 @@ rspamd_mmaped_file_reindex (rspamd_mempool_t *pool,
                        msg_err_pool ("cannot open file: %s", strerror (errno));
                        unlink (lock);
                        g_free (lock);
-                       rspamd_file_unlock (lock_fd, FALSE);
                        close (lock_fd);
                        g_free (backup);
                        return NULL;
@@ -497,7 +489,6 @@ rspamd_mmaped_file_reindex (rspamd_mempool_t *pool,
                        close (fd);
                        unlink (lock);
                        g_free (lock);
-                       rspamd_file_unlock (lock_fd, FALSE);
                        close (lock_fd);
                        g_free (backup);
                        return NULL;
@@ -533,11 +524,8 @@ rspamd_mmaped_file_reindex (rspamd_mempool_t *pool,
        g_free (backup);
        unlink (lock);
        g_free (lock);
-       rspamd_file_unlock (lock_fd, FALSE);
        close (lock_fd);
 
-       rspamd_file_unlock (new->fd, FALSE);
-
        return new;
 
 }
@@ -693,11 +681,15 @@ rspamd_mmaped_file_create (const gchar *filename,
        };
        struct stat_file_block block = { 0, 0, 0 };
        struct rspamd_stat_tokenizer *tokenizer;
-       gint fd;
+       gint fd, lock_fd;
        guint buflen = 0, nblocks;
-       gchar *buf = NULL;
+       gchar *buf = NULL, *lock;
        gpointer tok_conf;
        gsize tok_conf_len;
+       struct timespec sleep_ts = {
+                       .tv_sec = 0,
+                       .tv_nsec = 1000000
+       };
 
        if (size <
                sizeof (struct stat_file_header) + sizeof (struct stat_file_section) +
@@ -708,6 +700,24 @@ rspamd_mmaped_file_create (const gchar *filename,
                return -1;
        }
 
+       lock = g_strconcat (filename, ".lock", NULL);
+       lock_fd = open (lock, O_WRONLY|O_CREAT|O_EXCL, 00600);
+
+       if (lock_fd == -1) {
+               /* Wait for lock */
+               lock_fd = open (lock, O_WRONLY|O_CREAT|O_EXCL, 00600);
+               if (lock_fd != -1) {
+                       unlink (lock);
+                       close (lock_fd);
+                       g_free (lock);
+
+                       return 0;
+               }
+               else {
+                       nanosleep (&sleep_ts, NULL);
+               }
+       }
+
        nblocks =
                (size - sizeof (struct stat_file_header) -
                sizeof (struct stat_file_section)) / sizeof (struct stat_file_block);
@@ -719,6 +729,10 @@ rspamd_mmaped_file_create (const gchar *filename,
                        filename,
                        errno,
                        strerror (errno));
+               unlink (lock);
+               close (lock_fd);
+               g_free (lock);
+
                return -1;
        }
 
@@ -742,6 +756,9 @@ rspamd_mmaped_file_create (const gchar *filename,
                        errno,
                        strerror (errno));
                close (fd);
+               unlink (lock);
+               close (lock_fd);
+               g_free (lock);
 
                return -1;
        }
@@ -753,6 +770,9 @@ rspamd_mmaped_file_create (const gchar *filename,
                        errno,
                        strerror (errno));
                close (fd);
+               unlink (lock);
+               close (lock_fd);
+               g_free (lock);
 
                return -1;
        }
@@ -773,6 +793,9 @@ rspamd_mmaped_file_create (const gchar *filename,
                                        strerror (errno));
                                close (fd);
                                g_free (buf);
+                               unlink (lock);
+                               close (lock_fd);
+                               g_free (lock);
 
                                return -1;
                        }
@@ -789,6 +812,10 @@ rspamd_mmaped_file_create (const gchar *filename,
                                        g_free (buf);
                                }
 
+                               unlink (lock);
+                               close (lock_fd);
+                               g_free (lock);
+
                                return -1;
                        }
                        nblocks--;
@@ -801,6 +828,10 @@ rspamd_mmaped_file_create (const gchar *filename,
                g_free (buf);
        }
 
+       unlink (lock);
+       close (lock_fd);
+       g_free (lock);
+
        return 0;
 }
 
@@ -866,7 +897,7 @@ rspamd_mmaped_file_init (struct rspamd_stat_ctx *ctx,
                }
 
                mf = rspamd_mmaped_file_open (cfg->cfg_pool, filename, size, stf);
-        }
+       }
 
        return (gpointer)mf;
 }