Slightly untested initial ringlog.

src/agents/store/CMakeLists.txt

@@ -22,6 +22,7 @@ add_executable(bongostore
 	properties.c
 	query-builder.c
 	query-parser.c
+	ringlog.c
 	search.c
 	store.c
 	stored.c

src/agents/store/command.c

@@ -249,7 +249,10 @@ StoreCommandLoop(StoreClient *client)
         if (-1 == ccode || ccode >= CONN_BUFSIZE) {
             break;
         }
-                        
+        char command_message[256];
+        snprintf(command_message, 255, "-> %s", client->buffer);
+        Ringlog(command_message);
+        
         memset(tokens, 0, sizeof(tokens));
         n = CommandSplit(client->buffer, tokens, TOK_ARR_SZ);
         if (0 == n) {
@@ -1318,8 +1321,13 @@ StoreCommandLoop(StoreClient *client)
         if (ccode >= 0) {
             ccode = ConnFlush(client->conn);
         }
+    
+        command_message[0] = '<';
+        command_message[1] = '-';
+        Ringlog(command_message);
     }
     
+    
     return ccode;
 }
 

src/agents/store/ringlog.c

@@ -0,0 +1,67 @@
+#include "stored.h"
+#include "messages.h"
+#include "lock.h"
+
+/* ring log for debugging purposes */
+
+typedef struct {
+	time_t timestamp;
+	char message[256];
+} RingLogItem;
+
+#define RINGLOG_SIZE 200
+
+static RingLogItem ringlog[RINGLOG_SIZE];
+// ringlog_pos points to the next "free" ringlog entry.
+static int ringlog_pos = 0;
+static XplMutex ringlog_lock;
+
+void
+RinglogInit()
+{
+	// initialise lock; this must be held to access the ringlog.
+	XplMutexInit(ringlog_lock);
+	
+	// clear the ringlog.
+	memset(ringlog, 0, sizeof(ringlog));
+}
+
+void
+Ringlog(char *message)
+{
+	XplMutexLock(ringlog_lock);
+	
+	// find the next ring log entry and write into it
+	ringlog[ringlog_pos].timestamp = time(NULL);
+	strncpy(ringlog[ringlog_pos].message, message, 255);
+	
+	// advance the ring pointer, and wrap around if necessary
+	ringlog_pos++;
+	if (ringlog_pos == RINGLOG_SIZE) ringlog_pos = 0;
+	
+	XplMutexUnlock(ringlog_lock);
+}
+
+void
+RinglogDumpFilehandle(int fh)
+{
+	XplMutexLock(ringlog_lock);
+	
+	for (int i = ringlog_pos; i < ringlog_pos + RINGLOG_SIZE; i++) {
+		// print the next ring log entry - wraps by cunning use of modulo
+		char message[300];
+		size_t len = snprintf(message, 299, "%20s %s\n", 
+			ctime(&(ringlog[i % RINGLOG_SIZE].timestamp)),
+			ringlog[i % RINGLOG_SIZE].message);
+		write(fh, message, len);
+	}
+	
+	XplMutexUnlock(ringlog_lock);
+}
+
+void
+RinglogDumpConsole()
+{
+	// hope we still have STDOUT around?!
+	RinglogDumpFilehandle(1);
+}

src/agents/store/stored.c

@@ -188,7 +188,18 @@ int _NonAppCheckUnload(void)
 static void 
 SignalHandler(int sigtype) 
 {
-    BongoAgentHandleSignal(&StoreAgent.agent, sigtype);
+	if (sigtype == SIGSEGV) {
+		char path[XPL_MAX_PATH + 1];
+		int boomfile;
+		
+		snprintf(path, XPL_MAX_PATH, "%s/store-ringlog-%d", XPL_DEFAULT_WORK_DIR, (int)time(NULL));
+		boomfile = open(path, O_CREAT | O_WRONLY);
+		if (boomfile != -1) {
+			RinglogDumpFilehandle(boomfile);
+			close(boomfile);
+		}
+	}
+	BongoAgentHandleSignal(&StoreAgent.agent, sigtype);
 }
 
 
@@ -207,6 +218,8 @@ _XplServiceMain(int argc, char *argv[])
     int startupOpts;
 
     LogStart();
+    RinglogInit();
+    Ringlog("Started store daemon");
 
     if (XplSetEffectiveUser(MsgGetUnprivilegedUser()) < 0) {
         Log(LOG_ERROR, "Could not drop to unprivileged user '%s'", MsgGetUnprivilegedUser());
@@ -229,7 +242,9 @@ _XplServiceMain(int argc, char *argv[])
         Log(LOG_FATAL, "Couldn't initialize Bongo libraries");
         return -1;
     }
- 
+
+    Ringlog("Initialising libraries");
+
     MsgInit();
     cal_success = BongoCalInit(MsgGetDir(MSGAPI_DIR_DBF, NULL, 0));
     
@@ -263,7 +278,7 @@ _XplServiceMain(int argc, char *argv[])
     }
 
     /* Create a thread pool for managing connections */
-
+    Ringlog("Initialising threads");
     BongoQueueAgentGetThreadPoolParameters (&StoreAgent.agent, &minThreads, 
                                           &maxThreads, &minSleep);
     
@@ -298,12 +313,15 @@ _XplServiceMain(int argc, char *argv[])
 
     /* Start the server thread */
     MsgSetRecoveryFlag("store");
+    Ringlog("Starting main thread");
     XplStartMainThread(AGENT_NAME, &id, StoreServer, 8192, NULL, ccode);
+    Ringlog("Stopping main thread");
     
     XplUnloadApp(XplGetThreadID());
     MsgClearRecoveryFlag("store");
     
     g_mime_shutdown();
+    Ringlog("Shutdown complete");
     
     return 0;
 }

src/agents/store/stored.h

@@ -412,6 +412,12 @@ int MimeGetGuid(StoreClient *client, uint64_t guid, MimeReport **outReport);
 /** config.c **/
 BOOL StoreAgentReadConfiguration(BOOL *recover);
 
+/** ringlog.c **/
+void RinglogInit();
+void Ringlog(char *message);
+void RinglogDumpConsole();
+void RinglogDumpFilehandle(int fh);
+
 /** locking.c **/
 typedef enum {
 	LLOCK_NONE,