Allow passing a path with a trailing slash to mkdir

Some applications invoke mkdir() with a path that ends with a slash, and
expect that if the last component of the path does not exist, it will be
created. This indeed is the behaviour under Linux.

Author: mardy

source/fatdir.c

@@ -338,6 +338,7 @@ int _FAT_mkdir_r (struct _reent *r, const char *path, int mode) {
 	bool fileExists;
 	DIR_ENTRY dirEntry;
 	const char* pathEnd;
+	const char* lastSlash;
 	uint32_t parentCluster, dirCluster;
 	uint8_t newEntryData[DIR_ENTRY_DATA_SIZE];
 
@@ -376,11 +377,16 @@ int _FAT_mkdir_r (struct _reent *r, const char *path, int mode) {
 	}
 
 	// Get the directory it has to go in
-	pathEnd = strrchr (path, DIR_SEPARATOR);
+	pathEnd = NULL;
+	lastSlash = strchr (path, DIR_SEPARATOR);
+	while (lastSlash && lastSlash[1] != '\0') {
+		pathEnd = lastSlash;
+		lastSlash = strchr (pathEnd + 1, DIR_SEPARATOR);
+	}
 	if (pathEnd == NULL) {
 		// No path was specified
 		parentCluster = partition->cwdCluster;
-		pathEnd = path;
+		strncpy (dirEntry.filename, path, NAME_MAX - 1);
 	} else {
 		// Path was specified -- get the right parentCluster
 		// Recycling dirEntry, since it needs to be recreated anyway
@@ -391,11 +397,15 @@ int _FAT_mkdir_r (struct _reent *r, const char *path, int mode) {
 			return -1;
 		}
 		parentCluster = _FAT_directory_entryGetCluster (partition, dirEntry.entryData);
-		// Move the pathEnd past the last DIR_SEPARATOR
-		pathEnd += 1;
+
+		// Set the name -- remove the trailing '/', if present
+		strncpy (dirEntry.filename, pathEnd + 1, NAME_MAX - 1);
+		if (lastSlash && lastSlash != pathEnd) {
+			// replace the last '/' with a null byte
+			dirEntry.filename[lastSlash - pathEnd - 1] = '\0';
+		}
 	}
 	// Create the entry data
-	strncpy (dirEntry.filename, pathEnd, NAME_MAX - 1);
 	memset (dirEntry.entryData, 0, DIR_ENTRY_DATA_SIZE);
 
 	// Set the creation time and date