[apparmor] [patch] [parser]: create missing cache directory

[John Johansen]

This patch applies on top of the previous 2 cache patches. It does two
things, create the cache dir if it is missing, and moves the cache clearing
logic into the create cache routine, because if we are writing a new
cache .features file the cache dir should be cleared out.

Signed-off-by: John Johansen <john.johansen at canonical.com>

---
=== modified file 'parser/parser_main.c'
--- parser/parser_main.c	2013-09-23 22:26:51 +0000
+++ parser/parser_main.c	2013-09-23 23:09:21 +0000
@@ -1260,20 +1260,42 @@
 	return error;
 }
 
-static int create_cache(const char *path, const char *features)
+static int create_cache(const char *cachedir, const char *path,
+			const char *features)
 {
+	struct stat stat_file;
 	FILE * f = NULL;
 
+	if (cond_clear_cache && clear_cache_files(cacheloc) != 0)
+		goto error;
+
+create_file:
 	f = fopen(path, "w");
 	if (f) {
 		if (fwrite(features, strlen(features), 1, f) != 1 )
-			goto fail;
+			goto error;
 
 		fclose(f);
-	}
-
-	return 0;
-fail:
+
+
+		return 0;
+	}
+
+error:
+	/* does the dir exist? */
+	if (stat(cachedir, &stat_file) == -1) {
+		if (mkdir(cachedir, 0700) == 0)
+			goto create_file;
+		if (show_cache)
+			PERROR(_("Can't create cache directory: %s\n"), cachedir);
+	} else if (!S_ISDIR(stat_file.st_mode)) {
+		if (show_cache)
+			PERROR(_("File in cache directory location: %s\n"), cachedir);
+	} else {
+		if (show_cache)
+			PERROR(_("Can't update cache directory: %s\n"), cachedir);
+	}
+
 	if (show_cache)
 		PERROR("Cache write disabled: cannot create %s\n", path);
 	write_cache = 0;
@@ -1319,12 +1341,10 @@
 	get_flags_string(&cache_flags, cache_features_path);
 	if (cache_flags) {
 		if (strcmp(flags_string, cache_flags) != 0) {
-			if (write_cache && cond_clear_cache) {
-				if (clear_cache_files(cacheloc) ||
-				    create_cache(cache_features_path,
-						 flags_string)) {
+			if (write_cache) {
+				if (create_cache(cacheloc, cache_features_path,
+						 flags_string))
 					skip_read_cache = 1;
-				}
 			} else {
 				if (show_cache)
 					PERROR("Cache read/write disabled: %s does not match %s\n", FLAGS_FILE, cache_features_path);
@@ -1335,7 +1355,7 @@
 		free(cache_flags);
 		cache_flags = NULL;
 	} else if (write_cache) {
-		create_cache(cache_features_path, flags_string);
+		create_cache(cacheloc, cache_features_path, flags_string);
 	}
 
 	free(cache_features_path);