git-merge: show usage if run without arguments

diff --git a/fsck-objects.c b/fsck-objects.c
index 4ba3377aeffa4b0c7868943d688c9a8ed2f5ed08..4d994f3fc83d71501bbfde5159a869b4f2a38e99 100644 (file)
--- a/fsck-objects.c
+++ b/fsck-objects.c
@@ -14,12 +14,12 @@
 #define REACHABLE 0x0001
 #define SEEN      0x0002
 
-static int show_root = 0;
-static int show_tags = 0;
-static int show_unreachable = 0;
-static int check_full = 0;
-static int check_strict = 0;
-static int keep_cache_objects = 0;
+static int show_root;
+static int show_tags;
+static int show_unreachable;
+static int check_full;
+static int check_strict;
+static int keep_cache_objects;
 static unsigned char head_sha1[20];
 
 #ifdef NO_D_INO_IN_DIRENT
@@ -356,7 +356,7 @@ static void add_sha1_list(unsigned char *sha1, unsigned long ino)
        int nr;
 
        entry->ino = ino;
-       memcpy(entry->sha1, sha1, 20);
+       hashcpy(entry->sha1, sha1);
        nr = sha1_list.nr;
        if (nr == MAX_SHA1_ENTRIES) {
                fsck_sha1_list();
@@ -400,7 +400,7 @@ static void fsck_dir(int i, char *path)
        closedir(dir);
 }
 
-static int default_refs = 0;
+static int default_refs;
 
 static int fsck_handle_ref(const char *refname, const unsigned char *sha1)
 {
@@ -425,8 +425,23 @@ static int fsck_handle_ref(const char *refname, const unsigned char *sha1)
 static void get_default_heads(void)
 {
        for_each_ref(fsck_handle_ref);
-       if (!default_refs)
-               die("No default references");
+
+       /*
+        * Not having any default heads isn't really fatal, but
+        * it does mean that "--unreachable" no longer makes any
+        * sense (since in this case everything will obviously
+        * be unreachable by definition.
+        *
+        * Showing dangling objects is valid, though (as those
+        * dangling objects are likely lost heads).
+        *
+        * So we just print a warning about it, and clear the
+        * "show_unreachable" flag.
+        */
+       if (!default_refs) {
+               error("No default references");
+               show_unreachable = 0;
+       }
 }
 
 static void fsck_object_dir(const char *path)
@@ -443,7 +458,7 @@ static void fsck_object_dir(const char *path)
 static int fsck_head_link(void)
 {
        unsigned char sha1[20];
-       const char *git_HEAD = strdup(git_path("HEAD"));
+       const char *git_HEAD = xstrdup(git_path("HEAD"));
        const char *git_refs_heads_master = resolve_ref(git_HEAD, sha1, 1);
        int pfxlen = strlen(git_HEAD) - 4; /* strip .../.git/ part */
 
@@ -452,7 +467,7 @@ static int fsck_head_link(void)
        if (strncmp(git_refs_heads_master + pfxlen, "refs/heads/", 11))
                return error("HEAD points to something strange (%s)",
                             git_refs_heads_master + pfxlen);
-       if (!memcmp(null_sha1, sha1, 20))
+       if (is_null_sha1(sha1))
                return error("HEAD: not a valid git pointer");
        return 0;
 }