From: Shivam Garg <garg.shivam@samsung.com>
Date: Thu, 29 Dec 2016 07:00:07 +0000 (+0900)
Subject: Make logm to spit a message, before dropping messages if buffer overflows.
X-Git-Tag: 1.1_Public_Release~679
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=a80f26484608d27cc5ac9a7eda933cf3381b6637;p=rtos%2Ftinyara.git

Make logm to spit a message, before dropping messages if buffer overflows.

Change-Id: I6438fb53b11626a4f742c28cfd16ffe5d1832999
Signed-off-by: Shivam Garg <garg.shivam@samsung.com>
---

diff --git a/os/logm/logm.c b/os/logm/logm.c
index 72505c4..9cc3428 100644
--- a/os/logm/logm.c
+++ b/os/logm/logm.c
@@ -27,7 +27,7 @@
 
 #include "logm.h"
 
-char g_logm_rsvbuf[LOGM_RSVBUF_COUNT][LOGM_MAX_MSG_LEN];
+char g_logm_rsvbuf[LOGM_RSVBUF_COUNT + 1][LOGM_MAX_MSG_LEN];
 int g_logm_head;
 int g_logm_tail;
 int g_logm_count;
@@ -37,22 +37,43 @@ int logm_internal(int priority, const char *fmt, va_list ap)
 {
 	irqstate_t flags;
 	int ret = 0;
-
-	/* Need logic for set here */
+	buffer_state_t op;
 
 	if (g_logm_isready) {
 		flags = irqsave();
 
-		/* choose a available buffer */
-		/* This section will be optimized later */
 		if (g_logm_count < LOGM_RSVBUF_COUNT) {
+			op = LESS;
+		}
+		else if (g_logm_count == LOGM_RSVBUF_COUNT) {
+			op = EQUAL;
+		}
+		else {
+			op = GREATER;
+		}
+
+		switch (op) {
+		case LESS:
 			ret = vsnprintf((char *)&g_logm_rsvbuf[g_logm_tail], LOGM_MAX_MSG_LEN - 1, fmt, ap);
-			g_logm_tail += 1;
-			if (g_logm_tail >= LOGM_RSVBUF_COUNT) {
-				g_logm_tail -= LOGM_RSVBUF_COUNT;
-			}
-			g_logm_count++;
+			break;
+		case EQUAL:
+			ret = vsnprintf((char *)&g_logm_rsvbuf[g_logm_tail], LOGM_MAX_MSG_LEN - 1, "LOGM: Buffer Overflow dropping messages\n", ap);
+			break;
+		case GREATER:
+			irqrestore(flags);
+			return 0;
 		}
+		/* choose a available buffer */
+
+		if (ret > LOGM_MAX_MSG_LEN - 1) {
+			g_logm_rsvbuf[g_logm_tail][LOGM_MAX_MSG_LEN - 1] = '\n';
+		}
+		g_logm_tail += 1;
+		if (g_logm_tail >= (LOGM_RSVBUF_COUNT + 1)) {
+			g_logm_tail -= (LOGM_RSVBUF_COUNT + 1) ;
+		}
+		g_logm_count++;
+
 		irqrestore(flags);
 	} else {
 		/* Low Output: Sytem is not yet completely ready  */
diff --git a/os/logm/logm.h b/os/logm/logm.h
index 4bb5df1..db08d95 100644
--- a/os/logm/logm.h
+++ b/os/logm/logm.h
@@ -33,7 +33,14 @@
 /****************************************************************************
  * Private Declarations
  ****************************************************************************/
-#define LOGM_PRIVATE_SIGNO (13)
+
+enum buffer_state_e {
+	LESS = 0,
+	EQUAL = 1,
+	GREATER = 2
+};
+
+typedef enum buffer_state_e buffer_state_t;
 
 /* Structure for a single debug message */
 
diff --git a/os/logm/logm_process.c b/os/logm/logm_process.c
index 83b1d1b..0228879 100644
--- a/os/logm/logm_process.c
+++ b/os/logm/logm_process.c
@@ -33,7 +33,6 @@ int logm_task(int argc, char *argv[])
 	g_logm_head = 0;
 	g_logm_tail = 0;
 	g_logm_count = 0;
-
 	/* Now logm is ready */
 	g_logm_isready = 1;
 
@@ -45,8 +44,8 @@ int logm_task(int argc, char *argv[])
 		while (g_logm_count > 0) {
 			fputs(g_logm_rsvbuf[g_logm_head], stdout);
 			g_logm_head += 1;
-			if (g_logm_head >= LOGM_RSVBUF_COUNT) {
-				g_logm_head -= LOGM_RSVBUF_COUNT;
+			if (g_logm_head >= (LOGM_RSVBUF_COUNT + 1)) {
+				g_logm_head -= (LOGM_RSVBUF_COUNT + 1);
 			}
 			g_logm_count--;
 		}