Further code review for pg_stat_ssl patch.

Fix additional bogosity in commit 9029f4b37406b21a.  Include the
BackendSslStatusBuffer in the BackendStatusShmemSize calculation,
avoid ugly and error-prone casts to char* and back, put related
code stanzas into a consistent order (and fix a couple of previous
instances of that sin).  All cosmetic except for the size oversight.

diff --git a/src/backend/postmaster/pgstat.c b/src/backend/postmaster/pgstat.c
index 887095def06661e3d4471fdecdcc683ae6558768..ab018c474140a39dd9f568168047c2133a576fc8 100644 (file)
--- a/src/backend/postmaster/pgstat.c
+++ b/src/backend/postmaster/pgstat.c
@@ -2478,8 +2478,8 @@ pgstat_fetch_global(void)
 
 static PgBackendStatus *BackendStatusArray = NULL;
 static PgBackendStatus *MyBEEntry = NULL;
-static char *BackendClientHostnameBuffer = NULL;
 static char *BackendAppnameBuffer = NULL;
+static char *BackendClientHostnameBuffer = NULL;
 static char *BackendActivityBuffer = NULL;
 static Size BackendActivityBufferSize = 0;
 #ifdef USE_SSL
@@ -2495,13 +2495,22 @@ BackendStatusShmemSize(void)
 {
        Size            size;
 
+       /* BackendStatusArray: */
        size = mul_size(sizeof(PgBackendStatus), MaxBackends);
+       /* BackendAppnameBuffer: */
+       size = add_size(size,
+                                       mul_size(NAMEDATALEN, MaxBackends));
+       /* BackendClientHostnameBuffer: */
        size = add_size(size,
                                        mul_size(NAMEDATALEN, MaxBackends));
+       /* BackendActivityBuffer: */
        size = add_size(size,
                                        mul_size(pgstat_track_activity_query_size, MaxBackends));
+#ifdef USE_SSL
+       /* BackendSslStatusBuffer: */
        size = add_size(size,
-                                       mul_size(NAMEDATALEN, MaxBackends));
+                                       mul_size(sizeof(PgBackendSSLStatus), MaxBackends));
+#endif
        return size;
 }
 
@@ -2566,26 +2575,6 @@ CreateSharedBackendStatus(void)
                }
        }
 
-#ifdef USE_SSL
-       /* Create or attach to the shared SSL status buffer */
-       size = mul_size(sizeof(PgBackendSSLStatus), MaxBackends);
-       BackendSslStatusBuffer = (PgBackendSSLStatus *)
-               ShmemInitStruct("Backend SSL Status Buffer", size, &found);
-
-       if (!found)
-       {
-               MemSet(BackendSslStatusBuffer, 0, size);
-
-               /* Initialize st_sslstatus pointers. */
-               buffer = (char *) BackendSslStatusBuffer;
-               for (i = 0; i < MaxBackends; i++)
-               {
-                       BackendStatusArray[i].st_sslstatus = (PgBackendSSLStatus *) buffer;
-                       buffer += sizeof(PgBackendSSLStatus);
-               }
-       }
-#endif
-
        /* Create or attach to the shared activity buffer */
        BackendActivityBufferSize = mul_size(pgstat_track_activity_query_size,
                                                                                 MaxBackends);
@@ -2606,6 +2595,28 @@ CreateSharedBackendStatus(void)
                        buffer += pgstat_track_activity_query_size;
                }
        }
+
+#ifdef USE_SSL
+       /* Create or attach to the shared SSL status buffer */
+       size = mul_size(sizeof(PgBackendSSLStatus), MaxBackends);
+       BackendSslStatusBuffer = (PgBackendSSLStatus *)
+               ShmemInitStruct("Backend SSL Status Buffer", size, &found);
+
+       if (!found)
+       {
+               PgBackendSSLStatus *ptr;
+
+               MemSet(BackendSslStatusBuffer, 0, size);
+
+               /* Initialize st_sslstatus pointers. */
+               ptr = BackendSslStatusBuffer;
+               for (i = 0; i < MaxBackends; i++)
+               {
+                       BackendStatusArray[i].st_sslstatus = ptr;
+                       ptr++;
+               }
+       }
+#endif
 }
 
 
@@ -2932,11 +2943,11 @@ pgstat_read_current_status(void)
        volatile PgBackendStatus *beentry;
        LocalPgBackendStatus *localtable;
        LocalPgBackendStatus *localentry;
+       char       *localappname,
+                          *localactivity;
 #ifdef USE_SSL
        PgBackendSSLStatus *localsslstatus;
 #endif
-       char       *localappname,
-                          *localactivity;
        int                     i;
 
        Assert(!pgStatRunningInCollector);
@@ -2951,15 +2962,15 @@ pgstat_read_current_status(void)
        localappname = (char *)
                MemoryContextAlloc(pgStatLocalContext,
                                                   NAMEDATALEN * MaxBackends);
+       localactivity = (char *)
+               MemoryContextAlloc(pgStatLocalContext,
+                                                  pgstat_track_activity_query_size * MaxBackends);
 #ifdef USE_SSL
        localsslstatus = (PgBackendSSLStatus *)
                MemoryContextAlloc(pgStatLocalContext,
                                                   sizeof(PgBackendSSLStatus) * MaxBackends);
 #endif
 
-       localactivity = (char *)
-               MemoryContextAlloc(pgStatLocalContext,
-                                                  pgstat_track_activity_query_size * MaxBackends);
        localNumBackends = 0;
 
        beentry = BackendStatusArray;