General ref log reading improvements.

diff --git a/describe.c b/describe.c
index 4866510eafa19fbfe74e11d20e5d2d1a0a44fd4b..8a9cd5d52c555330c512b977179ab030ccd28861 100644 (file)
--- a/describe.c
+++ b/describe.c
@@ -11,7 +11,6 @@ static const char describe_usage[] =
 static int all = 0;    /* Default to annotated tags only */
 static int tags = 0;   /* But allow any tags if --tags is specified */
 
-#define DEFAULT_ABBREV 8 /* maybe too many */
 static int abbrev = DEFAULT_ABBREV;
 
 static int names = 0, allocs = 0;
@@ -106,11 +105,11 @@ static void describe(char *arg, int last_one)
        static int initialized = 0;
        struct commit_name *n;
 
-       if (get_sha1(arg, sha1) < 0)
-               usage(describe_usage);
+       if (get_sha1(arg, sha1))
+               die("Not a valid object name %s", arg);
        cmit = lookup_commit_reference(sha1);
        if (!cmit)
-               usage(describe_usage);
+               die("%s is not a valid '%s' object", arg, commit_type);
 
        if (!initialized) {
                initialized = 1;
@@ -155,7 +154,7 @@ int main(int argc, char **argv)
                        tags = 1;
                else if (!strncmp(arg, "--abbrev=", 9)) {
                        abbrev = strtoul(arg + 9, NULL, 10);
-                       if (abbrev < 4 || 40 <= abbrev)
+                       if (abbrev < MINIMUM_ABBREV || 40 <= abbrev)
                                abbrev = DEFAULT_ABBREV;
                }
                else