git-hash-object: Add --stdin-paths option

This allows multiple paths to be specified on stdin.

Signed-off-by: Adam Roben <aroben@apple.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/hash-object.c b/hash-object.c
index 61e7160..0a7ac2f 100644
--- a/hash-object.c
+++ b/hash-object.c
@@ -6,6 +6,7 @@
  */
 #include "cache.h"
 #include "blob.h"
+#include "quote.h"
 
 static void hash_object(const char *path, enum object_type type, int write_object)
 {
@@ -20,6 +21,7 @@
 		    ? "Unable to add %s to database"
 		    : "Unable to hash %s", path);
 	printf("%s\n", sha1_to_hex(sha1));
+	maybe_flush_or_die(stdout, "hash to stdout");
 }
 
 static void hash_stdin(const char *type, int write_object)
@@ -30,8 +32,27 @@
 	printf("%s\n", sha1_to_hex(sha1));
 }
 
+static void hash_stdin_paths(const char *type, int write_objects)
+{
+	struct strbuf buf, nbuf;
+
+	strbuf_init(&buf, 0);
+	strbuf_init(&nbuf, 0);
+	while (strbuf_getline(&buf, stdin, '\n') != EOF) {
+		if (buf.buf[0] == '"') {
+			strbuf_reset(&nbuf);
+			if (unquote_c_style(&nbuf, buf.buf, NULL))
+				die("line is badly quoted");
+			strbuf_swap(&buf, &nbuf);
+		}
+		hash_object(buf.buf, type_from_string(type), write_objects);
+	}
+	strbuf_release(&buf);
+	strbuf_release(&nbuf);
+}
+
 static const char hash_object_usage[] =
-"git-hash-object [-t <type>] [-w] [--stdin] <file>...";
+"git-hash-object [ [-t <type>] [-w] [--stdin] <file>... | --stdin-paths < <list-of-paths> ]";
 
 int main(int argc, char **argv)
 {
@@ -42,6 +63,7 @@
 	int prefix_length = -1;
 	int no_more_flags = 0;
 	int hashstdin = 0;
+	int stdin_paths = 0;
 
 	git_config(git_default_config);
 
@@ -65,7 +87,19 @@
 			}
 			else if (!strcmp(argv[i], "--help"))
 				usage(hash_object_usage);
+			else if (!strcmp(argv[i], "--stdin-paths")) {
+				if (hashstdin) {
+					error("Can't use --stdin-paths with --stdin");
+					usage(hash_object_usage);
+				}
+				stdin_paths = 1;
+
+			}
 			else if (!strcmp(argv[i], "--stdin")) {
+				if (stdin_paths) {
+					error("Can't use %s with --stdin-paths", argv[i]);
+					usage(hash_object_usage);
+				}
 				if (hashstdin)
 					die("Multiple --stdin arguments are not supported");
 				hashstdin = 1;
@@ -76,6 +110,11 @@
 		else {
 			const char *arg = argv[i];
 
+			if (stdin_paths) {
+				error("Can't specify files (such as \"%s\") with --stdin-paths", arg);
+				usage(hash_object_usage);
+			}
+
 			if (hashstdin) {
 				hash_stdin(type, write_object);
 				hashstdin = 0;
@@ -87,6 +126,10 @@
 			no_more_flags = 1;
 		}
 	}
+
+	if (stdin_paths)
+		hash_stdin_paths(type, write_object);
+
 	if (hashstdin)
 		hash_stdin(type, write_object);
 	return 0;