1 files changed, 100 insertions, 7 deletions

diff --git a/submodule.c b/submodule.c
index 86aad653b7..676d48fb33 100644
--- a/submodule.c
+++ b/submodule.c
@@ -4,22 +4,33 @@
 #include "diff.h"
 #include "commit.h"
 #include "revision.h"
+#include "run-command.h"
+#include "diffcore.h"
 
-int add_submodule_odb(const char *path)
+static int add_submodule_odb(const char *path)
 {
 	struct strbuf objects_directory = STRBUF_INIT;
 	struct alternate_object_database *alt_odb;
+	int ret = 0;
+	const char *git_dir;
 
-	strbuf_addf(&objects_directory, "%s/.git/objects/", path);
-	if (!is_directory(objects_directory.buf))
-		return -1;
-
+	strbuf_addf(&objects_directory, "%s/.git", path);
+	git_dir = read_gitfile_gently(objects_directory.buf);
+	if (git_dir) {
+		strbuf_reset(&objects_directory);
+		strbuf_addstr(&objects_directory, git_dir);
+	}
+	strbuf_addstr(&objects_directory, "/objects/");
+	if (!is_directory(objects_directory.buf)) {
+		ret = -1;
+		goto done;
+	}
 	/* avoid adding it twice */
 	for (alt_odb = alt_odb_list; alt_odb; alt_odb = alt_odb->next)
 		if (alt_odb->name - alt_odb->base == objects_directory.len &&
 				!strncmp(alt_odb->base, objects_directory.buf,
 					objects_directory.len))
-			return 0;
+			goto done;
 
 	alt_odb = xmalloc(objects_directory.len + 42 + sizeof(*alt_odb));
 	alt_odb->next = alt_odb_list;
@@ -30,11 +41,14 @@ int add_submodule_odb(const char *path)
 	alt_odb->name[41] = '\0';
 	alt_odb_list = alt_odb;
 	prepare_alt_odb();
-	return 0;
+done:
+	strbuf_release(&objects_directory);
+	return ret;
 }
 
 void show_submodule_summary(FILE *f, const char *path,
 		unsigned char one[20], unsigned char two[20],
+		unsigned dirty_submodule,
 		const char *del, const char *add, const char *reset)
 {
 	struct rev_info rev;
@@ -79,6 +93,16 @@ void show_submodule_summary(FILE *f, const char *path,
 			message = "(revision walker failed)";
 	}
 
+	if (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)
+		fprintf(f, "Submodule %s contains untracked content\n", path);
+	if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
+		fprintf(f, "Submodule %s contains modified content\n", path);
+
+	if (!hashcmp(one, two)) {
+		strbuf_release(&sb);
+		return;
+	}
+
 	strbuf_addf(&sb, "Submodule %s %s..", path,
 			find_unique_abbrev(one, DEFAULT_ABBREV));
 	if (!fast_backward && !fast_forward)
@@ -112,3 +136,72 @@ void show_submodule_summary(FILE *f, const char *path,
 	}
 	strbuf_release(&sb);
 }
+
+unsigned is_submodule_modified(const char *path, int ignore_untracked)
+{
+	ssize_t len;
+	struct child_process cp;
+	const char *argv[] = {
+		"status",
+		"--porcelain",
+		NULL,
+		NULL,
+	};
+	struct strbuf buf = STRBUF_INIT;
+	unsigned dirty_submodule = 0;
+	const char *line, *next_line;
+	const char *git_dir;
+
+	strbuf_addf(&buf, "%s/.git", path);
+	git_dir = read_gitfile_gently(buf.buf);
+	if (!git_dir)
+		git_dir = buf.buf;
+	if (!is_directory(git_dir)) {
+		strbuf_release(&buf);
+		/* The submodule is not checked out, so it is not modified */
+		return 0;
+
+	}
+	strbuf_reset(&buf);
+
+	if (ignore_untracked)
+		argv[2] = "-uno";
+
+	memset(&cp, 0, sizeof(cp));
+	cp.argv = argv;
+	cp.env = local_repo_env;
+	cp.git_cmd = 1;
+	cp.no_stdin = 1;
+	cp.out = -1;
+	cp.dir = path;
+	if (start_command(&cp))
+		die("Could not run git status --porcelain");
+
+	len = strbuf_read(&buf, cp.out, 1024);
+	line = buf.buf;
+	while (len > 2) {
+		if ((line[0] == '?') && (line[1] == '?')) {
+			dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
+			if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
+				break;
+		} else {
+			dirty_submodule |= DIRTY_SUBMODULE_MODIFIED;
+			if (ignore_untracked ||
+			    (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED))
+				break;
+		}
+		next_line = strchr(line, '\n');
+		if (!next_line)
+			break;
+		next_line++;
+		len -= (next_line - line);
+		line = next_line;
+	}
+	close(cp.out);
+
+	if (finish_command(&cp))
+		die("git status --porcelain failed");
+
+	strbuf_release(&buf);
+	return dirty_submodule;
+}