put flash writes in a mutex lock

1 files changed, 22 insertions, 16 deletions

diff --git a/flash.c b/flash.c
index a242284..34f6e7f 100644
--- a/flash.c
+++ b/flash.c
@@ -259,7 +259,7 @@ bool persistence_unfreeze(char* dest, void* result, unsigned int len, uint32_t v
 
 }
 
-int readUserBlock(FlashStruct *mem)
+static int readUserBlock(FlashStruct *mem)
 {
 
 	// try to unfreeze the main file
@@ -295,31 +295,37 @@ void writeUserBlock(FlashStruct *mem, int addr, int numbytes)
 	// *** that the main file is valid before backing it up I guess...  ***
 	// *** but I don't think this situation should arise.				***
 
+	static GMutex mutex;
+
+	g_mutex_lock (&mutex);
+
 	if (!globals.Flags.flash_writes_suspended) {
 
 		// backup the main copy of the file
-		if (globals.Flags.shutdown_started) return;
-
-		globals.Flags.flash_write_in_progress = TRUE;
-		bool backup_ok = persistence_copyfile(MAINFILE, BACKUPFILE);
-		globals.Flags.flash_write_in_progress = FALSE;
+		if (!globals.Flags.shutdown_started) {
 
-		if (backup_ok) {
-			if (globals.Flags.shutdown_started) return;
 			globals.Flags.flash_write_in_progress = TRUE;
+			bool backup_ok = persistence_copyfile(MAINFILE, BACKUPFILE);
+			globals.Flags.flash_write_in_progress = FALSE;
+
+			if (backup_ok && !globals.Flags.shutdown_started) {
+				globals.Flags.flash_write_in_progress = TRUE;
 
-			if (!persistence_freeze(MAINFILE, mem, addr, numbytes, sizeof(*mem), 0)) {
-				if (errno != PERSIST_ERR_COULDNTWRITE) {
-					printf("Error while trying to write, %d. **Write did not happen!!!**\n", errno);
-				} else {
-					printf("Error while writing data to disk. **File is potentially corrupt!**\n");
+				if (!persistence_freeze(MAINFILE, mem, addr, numbytes, sizeof(*mem), 0)) {
+					if (errno != PERSIST_ERR_COULDNTWRITE) {
+						printf("Error while trying to write, %d. **Write did not happen!!!**\n", errno);
+					} else {
+						printf("Error while writing data to disk. **File is potentially corrupt!**\n");
+					}
 				}
+				globals.Flags.flash_write_in_progress = FALSE;
+			} else {
+				printf("Could not backup current file. **Write did not happen!!!**\n");
 			}
-			globals.Flags.flash_write_in_progress = FALSE;
-		} else {
-			printf("Could not backup current file. **Write did not happen!!!**\n");
 		}
 	}
+
+	g_mutex_unlock (&mutex);
 }