Minor improvement: avoid assuming that GetLastError value cannot be

affected by CloseHandle() or Sleep().

diff --git a/src/backend/port/win32_shmem.c b/src/backend/port/win32_shmem.c
index ed485ea80f8bc7e0c803e77b9042802251204c07..5651a31e44cf697c6b32b15e0c59a5024ef3a9a1 100644 (file)
--- a/src/backend/port/win32_shmem.c
+++ b/src/backend/port/win32_shmem.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1996-2009, PostgreSQL Global Development Group
  *
  * IDENTIFICATION
- *   $PostgreSQL: pgsql/src/backend/port/win32_shmem.c,v 1.9 2009/05/05 09:48:51 mha Exp $
+ *   $PostgreSQL: pgsql/src/backend/port/win32_shmem.c,v 1.10 2009/05/05 21:51:46 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -158,12 +158,13 @@ PGSharedMemoryCreate(Size size, bool makePrivate, int port)
 
        /*
         * If the segment already existed, CreateFileMapping() will return a
-        * handle to the existing one.
+        * handle to the existing one and set ERROR_ALREADY_EXISTS.
         */
        if (GetLastError() == ERROR_ALREADY_EXISTS)
        {
-           CloseHandle(hmap);      /* Close the old handle, since we got a valid
+           CloseHandle(hmap);      /* Close the handle, since we got a valid
                                     * one to the previous segment. */
+           hmap = NULL;
            Sleep(1000);
            continue;
        }
@@ -171,10 +172,10 @@ PGSharedMemoryCreate(Size size, bool makePrivate, int port)
    }
 
    /*
-    * If the last call in the loop still returned ERROR_ALREADY_EXISTS, this shared memory
-    * segment exists and we assume it belongs to somebody else.
+    * If the last call in the loop still returned ERROR_ALREADY_EXISTS, this
+    * shared memory segment exists and we assume it belongs to somebody else.
     */
-   if (GetLastError() == ERROR_ALREADY_EXISTS)
+   if (!hmap)
        ereport(FATAL,
             (errmsg("pre-existing shared memory block is still in use"),
              errhint("Check if there are any old server processes still running, and terminate them.")));