Reduce stat() calls

diff --git a/ccache.c b/ccache.c
index b0b38cad6393e2849ddd999aa3a95f83283d0eb1..1b9467c3fddad436431d03c6e4f294b5a7d6d848 100644 (file)
--- a/ccache.c
+++ b/ccache.c
@@ -73,7 +73,7 @@ static char *current_working_dir;
 char *cache_dir = NULL;
 
 /* the directory for temporary files */
-static char *temp_dir;
+static const char* temp_dir();
 
 /* the debug logfile name, if set */
 char *cache_logfile = NULL;
@@ -250,6 +250,25 @@ clean_up_tmp_files()
        }
 }
 
+static const char*
+temp_dir() {
+       static char* path = NULL;
+       if (path) return path;  /* Memoize */
+       path = getenv("CCACHE_TEMPDIR");
+       if (!path) {
+               path = format("%s/tmp", cache_dir);
+       }
+
+       /* make sure the temp dir exists */
+       if (create_dir(path) != 0) {
+               fprintf(stderr,
+                       "ccache: failed to create %s (%s)\n",
+                       path, strerror(errno));
+               exit(1);
+       }
+       return path;
+}
+
 /*
  * Transform a name to a full path into the cache directory, creating needed
  * sublevels if needed. Caller frees.
@@ -674,6 +693,17 @@ to_cache(struct args *args)
 
        stats_update_size(STATS_TOCACHE, added_bytes / 1024, added_files);
 
+       /* Make sure we have a CACHEDIR.TAG
+        * This can be almost anywhere, but might as well do it near the end
+        * as if we exit early we save the stat call
+        */
+       if (create_cachedirtag(cache_dir) != 0) {
+               cc_log("Failed to create %s/CACHEDIR.TAG (%s)\n",
+                       cache_dir, strerror(errno));
+               stats_update(STATS_ERROR);
+               failed();
+       }
+
        free(tmp_obj);
        free(tmp_stderr);
        free(tmp_stdout);
@@ -707,8 +737,8 @@ get_object_name_from_cpp(struct args *args, struct mdfour *hash)
 
        /* now the run */
        path_stdout = format("%s/%s.tmp.%s.%s",
-                            temp_dir, input_base, tmp_string(), i_extension);
-       path_stderr = format("%s/tmp.cpp_stderr.%s", temp_dir, tmp_string());
+                            temp_dir(), input_base, tmp_string(), i_extension);
+       path_stderr = format("%s/tmp.cpp_stderr.%s", temp_dir(), tmp_string());
 
        time_of_compilation = time(NULL);
 
@@ -2117,11 +2147,6 @@ ccache_main(int argc, char *argv[])
 
        check_cache_dir();
 
-       temp_dir = getenv("CCACHE_TEMPDIR");
-       if (!temp_dir) {
-               temp_dir = format("%s/tmp", cache_dir);
-       }
-
        base_dir = getenv("CCACHE_BASEDIR");
        if (base_dir && base_dir[0] != '/') {
                cc_log("Ignoring non-absolute base directory %s", base_dir);
@@ -2140,23 +2165,6 @@ ccache_main(int argc, char *argv[])
                exit(1);
        }
 
-       /* make sure the temp dir exists */
-       if (create_dir(temp_dir) != 0) {
-               fprintf(stderr,
-                       "ccache: failed to create %s (%s)\n",
-                       temp_dir, strerror(errno));
-               exit(1);
-       }
-
-       if (!getenv("CCACHE_READONLY")) {
-               if (create_cachedirtag(cache_dir) != 0) {
-                       fprintf(stderr,
-                               "ccache: failed to create %s/CACHEDIR.TAG (%s)\n",
-                               cache_dir, strerror(errno));
-                       exit(1);
-               }
-       }
-
        ccache(argc, argv);
        return 1;
 }