git-commit: exit non-zero if we fail to commit the index

drafnel · gitster · commit 5a9dd3998fb4 · 2008-01-23T10:10:11.000-08:00
In certain rare cases, the creation of the commit object
and update of HEAD can succeed, but then installing the
updated index will fail. This is most likely caused by a
full disk or exceeded disk quota. When this happens the
new index file will be removed, and the repository will
be left with the original now-out-of-sync index. The
user can recover with a "git reset HEAD" once the disk
space issue is resolved.

We should detect this failure and offer the user some
helpful guidance.

Signed-off-by: Brandon Casey &lt;casey@nrlssc.navy.mil&gt;
Signed-off-by: Junio C Hamano &lt;gitster@pobox.com&gt;
diff --git a/builtin-commit.c b/builtin-commit.c
@@ -122,19 +122,23 @@ static void rollback_index_files(void)
 	}
 }
 
-static void commit_index_files(void)
+static int commit_index_files(void)
 {
+	int err = 0;
+
 	switch (commit_style) {
 	case COMMIT_AS_IS:
 		break; /* nothing to do */
 	case COMMIT_NORMAL:
-		commit_lock_file(&index_lock);
+		err = commit_lock_file(&index_lock);
 		break;
 	case COMMIT_PARTIAL:
-		commit_lock_file(&index_lock);
+		err = commit_lock_file(&index_lock);
 		rollback_lock_file(&false_lock);
 		break;
 	}
+
+	return err;
 }
 
 /*
@@ -926,7 +930,10 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
 	unlink(git_path("MERGE_HEAD"));
 	unlink(git_path("MERGE_MSG"));
 
-	commit_index_files();
+	if (commit_index_files())
+		die ("Repository has been updated, but unable to write\n"
+		     "new_index file. Check that disk is not full or quota is\n"
+		     "not exceeded, and then \"git reset HEAD\" to recover.");
 
 	rerere();
 	run_hook(get_index_file(), "post-commit", NULL);
