Test in git-init-db if the filemode can be trusted

... and if not, write an appropriate .git/config. Of course, that happens
only if no config file was yet created (by a template or a hook).

Signed-off-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/init-db.c b/init-db.c
index aabc09f..2a4aa3c 100644 (file)
--- a/init-db.c
+++ b/init-db.c
@@ -196,6 +196,43 @@ static void create_default_files(const char *git_dir,
        }
        path[len] = 0;
        copy_templates(path, len, template_path);
+
+       /*
+        * Find out if we can trust the executable bit.
+        */
+       safe_create_dir(path);
+       strcpy(path + len, "config");
+       if (access(path, R_OK) < 0) {
+               static const char contents[] =
+                       "#\n"
+                       "# This is the config file\n"
+                       "#\n"
+                       "\n"
+                       "; core variables\n"
+                       "[core]\n"
+                       "       ; Don't trust file modes\n"
+                       "       filemode = false\n"
+                       "\n";
+               FILE *config = fopen(path, "w");
+               struct stat st;
+
+               if (!config)
+                       die("Can not write to %s?", path);
+
+               fwrite(contents, sizeof(contents)-1, 1, config);
+
+               fclose(config);
+
+               if (!lstat(path, &st)) {
+                       struct stat st2;
+                       if (!chmod(path, st.st_mode ^ S_IXUSR) &&
+                                       !lstat(path, &st2) &&
+                                       st.st_mode != st2.st_mode)
+                               unlink(path);
+                       else
+                               fprintf(stderr, "Ignoring file modes\n");
+               }
+       }
 }
 
 static const char init_db_usage[] =