range-diff: libify the read_patches() function again

dscho · gitster · commit a2d474adf32c · 2021-02-04T17:16:42.000-08:00
In library functions, we do want to avoid the (simple, but rather final) `die()` calls, instead returning with a value indicating an error. Let's do exactly that in the code introduced in b66885a (range-diff: add section header instead of diff header, 2019-07-11) that wants to error out if a diff header could not be parsed. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/range-diff.c b/range-diff.c
@@ -135,9 +135,16 @@ static int read_patches(const char *range, struct string_list *list,
 			orig_len = len;
 			len = parse_git_diff_header(&root, &linenr, 0, line,
 						    len, size, &patch);
-			if (len < 0)
-				die(_("could not parse git header '%.*s'"),
-				    orig_len, line);
+			if (len < 0) {
+				error(_("could not parse git header '%.*s'"),
+				      orig_len, line);
+				free(util);
+				free(current_filename);
+				string_list_clear(list, 1);
+				strbuf_release(&buf);
+				strbuf_release(&contents);
+				return -1;
+			}
 			strbuf_addstr(&buf, " ## ");
 			if (patch.is_new > 0)
 				strbuf_addf(&buf, "%s (new)", patch.new_name);
