sequencer: factor out strbuf_read_file_or_whine()

Reduce code duplication by factoring out a function that reads an entire
file into a strbuf, or reports errors on stderr if something goes wrong.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

sequencer.c

@@ -1333,22 +1333,31 @@ static int count_commands(struct todo_list *todo_list)
 	return count;
 }
 
+static ssize_t strbuf_read_file_or_whine(struct strbuf *sb, const char *path)
+{
+	int fd;
+	ssize_t len;
+
+	fd = open(path, O_RDONLY);
+	if (fd < 0)
+		return error_errno(_("could not open '%s'"), path);
+	len = strbuf_read(sb, fd, 0);
+	close(fd);
+	if (len < 0)
+		return error(_("could not read '%s'."), path);
+	return len;
+}
+
 static int read_populate_todo(struct todo_list *todo_list,
 			struct replay_opts *opts)
 {
 	struct stat st;
 	const char *todo_file = get_todo_path(opts);
-	int fd, res;
+	int res;
 
 	strbuf_reset(&todo_list->buf);
-	fd = open(todo_file, O_RDONLY);
-	if (fd < 0)
-		return error_errno(_("could not open '%s'"), todo_file);
-	if (strbuf_read(&todo_list->buf, fd, 0) < 0) {
-		close(fd);
-		return error(_("could not read '%s'."), todo_file);
-	}
-	close(fd);
+	if (strbuf_read_file_or_whine(&todo_list->buf, todo_file) < 0)
+		return -1;
 
 	res = stat(todo_file, &st);
 	if (res)
@@ -2575,20 +2584,13 @@ int check_todo_list(void)
 	struct strbuf todo_file = STRBUF_INIT;
 	struct todo_list todo_list = TODO_LIST_INIT;
 	struct strbuf missing = STRBUF_INIT;
-	int advise_to_edit_todo = 0, res = 0, fd, i;
+	int advise_to_edit_todo = 0, res = 0, i;
 
 	strbuf_addstr(&todo_file, rebase_path_todo());
-	fd = open(todo_file.buf, O_RDONLY);
-	if (fd < 0) {
-		res = error_errno(_("could not open '%s'"), todo_file.buf);
+	if (strbuf_read_file_or_whine(&todo_list.buf, todo_file.buf) < 0) {
+		res = -1;
 		goto leave_check;
 	}
-	if (strbuf_read(&todo_list.buf, fd, 0) < 0) {
-		close(fd);
-		res = error(_("could not read '%s'."), todo_file.buf);
-		goto leave_check;
-	}
-	close(fd);
 	advise_to_edit_todo = res =
 		parse_insn_buffer(todo_list.buf.buf, &todo_list);
 
@@ -2604,17 +2606,10 @@ int check_todo_list(void)
 
 	todo_list_release(&todo_list);
 	strbuf_addstr(&todo_file, ".backup");
-	fd = open(todo_file.buf, O_RDONLY);
-	if (fd < 0) {
-		res = error_errno(_("could not open '%s'"), todo_file.buf);
+	if (strbuf_read_file_or_whine(&todo_list.buf, todo_file.buf) < 0) {
+		res = -1;
 		goto leave_check;
 	}
-	if (strbuf_read(&todo_list.buf, fd, 0) < 0) {
-		close(fd);
-		res = error(_("could not read '%s'."), todo_file.buf);
-		goto leave_check;
-	}
-	close(fd);
 	strbuf_release(&todo_file);
 	res = !!parse_insn_buffer(todo_list.buf.buf, &todo_list);
 
@@ -2682,15 +2677,8 @@ int skip_unnecessary_picks(void)
 	}
 	strbuf_release(&buf);
 
-	fd = open(todo_file, O_RDONLY);
-	if (fd < 0) {
-		return error_errno(_("could not open '%s'"), todo_file);
-	}
-	if (strbuf_read(&todo_list.buf, fd, 0) < 0) {
-		close(fd);
-		return error(_("could not read '%s'."), todo_file);
-	}
-	close(fd);
+	if (strbuf_read_file_or_whine(&todo_list.buf, todo_file) < 0)
+		return -1;
 	if (parse_insn_buffer(todo_list.buf.buf, &todo_list) < 0) {
 		todo_list_release(&todo_list);
 		return -1;
@@ -2799,17 +2787,11 @@ int rearrange_squash(void)
 	const char *todo_file = rebase_path_todo();
 	struct todo_list todo_list = TODO_LIST_INIT;
 	struct hashmap subject2item;
-	int res = 0, rearranged = 0, *next, *tail, fd, i;
+	int res = 0, rearranged = 0, *next, *tail, i;
 	char **subjects;
 
-	fd = open(todo_file, O_RDONLY);
-	if (fd < 0)
-		return error_errno(_("could not open '%s'"), todo_file);
-	if (strbuf_read(&todo_list.buf, fd, 0) < 0) {
-		close(fd);
-		return error(_("could not read '%s'."), todo_file);
-	}
-	close(fd);
+	if (strbuf_read_file_or_whine(&todo_list.buf, todo_file) < 0)
+		return -1;
 	if (parse_insn_buffer(todo_list.buf.buf, &todo_list) < 0) {
 		todo_list_release(&todo_list);
 		return -1;