Fix filename verification when in a subdirectory

When we are in a subdirectory of a git archive, we need to take the prefix
of that subdirectory into accoung when we verify filename arguments.

Noted by Matthias Lederhofer

This also uses the improved error reporting for all the other git commands
that use the revision parsing interfaces, not just git-rev-parse. Also, it
makes the error reporting for mixed filenames and argument flags clearer
(you cannot put flags after the start of the pathname list).

[jc: with fix to a trivial typo noticed by Timo Hirvonen]

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>

1 files changed, 23 insertions, 0 deletions

diff --git a/setup.c b/setup.c
index 36ede3d87..cce9bb806 100644
--- a/setup.c
+++ b/setup.c
@@ -62,6 +62,29 @@ const char *prefix_filename(const char *pfx, int pfx_len, const char *arg)
 	return path;
 }
 
+/*
+ * Verify a filename that we got as an argument for a pathspec
+ * entry. Note that a filename that begins with "-" never verifies
+ * as true, because even if such a filename were to exist, we want
+ * it to be preceded by the "--" marker (or we want the user to
+ * use a format like "./-filename")
+ */
+void verify_filename(const char *prefix, const char *arg)
+{
+	const char *name;
+	struct stat st;
+
+	if (*arg == '-')
+		die("bad flag '%s' used after filename", arg);
+	name = prefix ? prefix_filename(prefix, strlen(prefix), arg) : arg;
+	if (!lstat(name, &st))
+		return;
+	if (errno == ENOENT)
+		die("ambiguous argument '%s': unknown revision or filename\n"
+		    "Use '--' to separate filenames from revisions", arg);
+	die("'%s': %s", arg, strerror(errno));
+}
+
 const char **get_pathspec(const char *prefix, const char **pathspec)
 {
 	const char *entry = *pathspec;