# HG changeset patch
# User Maxim Dounin <mdounin@mdounin.ru>
# Date 1322057359 0
# Node ID 45272aab5eea5e02bf0aaf8b0da58c76533952d3
# Parent  13f108b9f3cfa7f6de3d3261160f7b0464cd8929
Unlock of shared memory zones on process crash.

If process exited abnormally while holding lock on some shared memory zone -
unlock it.  It may be not safe thing to do (as crash with lock held may
result in corrupted shared memory structure, and other processes will
subsequently crash while trying to access shared data), therefore complain
loudly if unlock succeeds.

diff --git a/src/os/unix/ngx_process.c b/src/os/unix/ngx_process.c
--- a/src/os/unix/ngx_process.c
+++ b/src/os/unix/ngx_process.c
@@ -22,6 +22,7 @@ typedef struct {
 static void ngx_execute_proc(ngx_cycle_t *cycle, void *data);
 static void ngx_signal_handler(int signo);
 static void ngx_process_get_status(void);
+static void ngx_unlock_mutexes(ngx_pid_t pid);
 
 
 int              ngx_argc;
@@ -497,17 +498,6 @@ ngx_process_get_status(void)
         }
 
 
-        if (ngx_accept_mutex_ptr) {
-
-            /*
-             * unlock the accept mutex if the abnormally exited process
-             * held it
-             */
-
-            ngx_shmtx_force_unlock(&ngx_accept_mutex, pid);
-        }
-
-
         one = 1;
         process = "unknown process";
 
@@ -545,6 +535,55 @@ ngx_process_get_status(void)
                           process, pid, WEXITSTATUS(status));
             ngx_processes[i].respawn = 0;
         }
+
+        ngx_unlock_mutexes(pid);
+    }
+}
+
+
+static void
+ngx_unlock_mutexes(ngx_pid_t pid)
+{ 
+    ngx_uint_t        i;
+    ngx_shm_zone_t   *shm_zone;
+    ngx_list_part_t  *part;
+    ngx_slab_pool_t  *sp;
+
+    /*
+     * unlock the accept mutex if the abnormally exited process
+     * held it
+     */
+
+    if (ngx_accept_mutex_ptr) {
+        ngx_shmtx_force_unlock(&ngx_accept_mutex, pid);
+    }
+
+    /*
+     * unlock shared memory mutexes if held by the abnormally exited
+     * process
+     */
+
+    part = (ngx_list_part_t *) &ngx_cycle->shared_memory.part;
+    shm_zone = part->elts;
+
+    for (i = 0; /* void */ ; i++) {
+
+        if (i >= part->nelts) {
+            if (part->next == NULL) {
+                break;
+            }
+            part = part->next;
+            shm_zone = part->elts;
+            i = 0;
+        }
+
+        sp = (ngx_slab_pool_t *) shm_zone[i].shm.addr;
+
+        if (ngx_shmtx_force_unlock(&sp->mutex, pid)) {
+            ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, 0,
+                          "shared memory zone \"%V\" was locked by %P",
+                          &shm_zone[i].shm.name, pid);
+        }
     }
 }