trailer: streamline trailer item create and add

Currently, creation and addition (to a list) of trailer items are spread
across multiple functions. Streamline this by only having 2 functions:
one to parse the user-supplied string, and one to add the parsed
information to a list.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

trailer.c

@@ -500,10 +500,31 @@ static int git_trailer_config(const char *conf_key, const char *value, void *cb)
 	return 0;
 }
 
-static int parse_trailer(struct strbuf *tok, struct strbuf *val, const char *trailer)
+static const char *token_from_item(struct trailer_item *item, char *tok)
+{
+	if (item->conf.key)
+		return item->conf.key;
+	if (tok)
+		return tok;
+	return item->conf.name;
+}
+
+static int token_matches_item(const char *tok, struct trailer_item *item, int tok_len)
+{
+	if (!strncasecmp(tok, item->conf.name, tok_len))
+		return 1;
+	return item->conf.key ? !strncasecmp(tok, item->conf.key, tok_len) : 0;
+}
+
+static int parse_trailer(struct strbuf *tok, struct strbuf *val,
+			 const struct conf_info **conf, const char *trailer)
 {
 	size_t len;
 	struct strbuf seps = STRBUF_INIT;
+	struct trailer_item *item;
+	int tok_len;
+	struct list_head *pos;
+
 	strbuf_addstr(&seps, separators);
 	strbuf_addch(&seps, '=');
 	len = strcspn(trailer, seps.buf);
@@ -523,74 +544,31 @@ static int parse_trailer(struct strbuf *tok, struct strbuf *val, const char *tra
 		strbuf_addstr(tok, trailer);
 		strbuf_trim(tok);
 	}
+
+	/* Lookup if the token matches something in the config */
+	tok_len = token_len_without_separator(tok->buf, tok->len);
+	*conf = &default_conf_info;
+	list_for_each(pos, &conf_head) {
+		item = list_entry(pos, struct trailer_item, list);
+		if (token_matches_item(tok->buf, item, tok_len)) {
+			char *tok_buf = strbuf_detach(tok, NULL);
+			*conf = &item->conf;
+			strbuf_addstr(tok, token_from_item(item, tok_buf));
+			free(tok_buf);
+			break;
+		}
+	}
+
 	return 0;
 }
 
-static const char *token_from_item(struct trailer_item *item, char *tok)
+static void add_trailer_item(struct list_head *head, char *tok, char *val,
-{
+			     const struct conf_info *conf)
-	if (item->conf.key)
-		return item->conf.key;
-	if (tok)
-		return tok;
-	return item->conf.name;
-}
-
-static struct trailer_item *new_trailer_item(struct trailer_item *conf_item,
-					     char *tok, char *val)
 {
 	struct trailer_item *new = xcalloc(sizeof(*new), 1);
-	new->value = val ? val : xstrdup("");
+	new->token = tok;
-
+	new->value = val;
-	if (conf_item) {
+	duplicate_conf(&new->conf, conf);
-		duplicate_conf(&new->conf, &conf_item->conf);
-		new->token = xstrdup(token_from_item(conf_item, tok));
-		free(tok);
-	} else {
-		duplicate_conf(&new->conf, &default_conf_info);
-		new->token = tok;
-	}
-
-	return new;
-}
-
-static int token_matches_item(const char *tok, struct trailer_item *item, int tok_len)
-{
-	if (!strncasecmp(tok, item->conf.name, tok_len))
-		return 1;
-	return item->conf.key ? !strncasecmp(tok, item->conf.key, tok_len) : 0;
-}
-
-static struct trailer_item *create_trailer_item(const char *string)
-{
-	struct strbuf tok = STRBUF_INIT;
-	struct strbuf val = STRBUF_INIT;
-	struct trailer_item *item;
-	int tok_len;
-	struct list_head *pos;
-
-	if (parse_trailer(&tok, &val, string))
-		return NULL;
-
-	tok_len = token_len_without_separator(tok.buf, tok.len);
-
-	/* Lookup if the token matches something in the config */
-	list_for_each(pos, &conf_head) {
-		item = list_entry(pos, struct trailer_item, list);
-		if (token_matches_item(tok.buf, item, tok_len))
-			return new_trailer_item(item,
-						strbuf_detach(&tok, NULL),
-						strbuf_detach(&val, NULL));
-	}
-
-	return new_trailer_item(NULL,
-				strbuf_detach(&tok, NULL),
-				strbuf_detach(&val, NULL));
-}
-
-static void add_trailer_item(struct list_head *head, struct trailer_item *new)
-{
-	if (!new)
-		return;
 	list_add_tail(&new->list, head);
 }
 
@@ -599,21 +577,28 @@ static void process_command_line_args(struct list_head *arg_head,
 {
 	struct string_list_item *tr;
 	struct trailer_item *item;
+	struct strbuf tok = STRBUF_INIT;
+	struct strbuf val = STRBUF_INIT;
+	const struct conf_info *conf;
 	struct list_head *pos;
 
 	/* Add a trailer item for each configured trailer with a command */
 	list_for_each(pos, &conf_head) {
 		item = list_entry(pos, struct trailer_item, list);
-		if (item->conf.command) {
+		if (item->conf.command)
-			struct trailer_item *new = new_trailer_item(item, NULL, NULL);
+			add_trailer_item(arg_head,
-			add_trailer_item(arg_head, new);
+					 xstrdup(token_from_item(item, NULL)),
-		}
+					 xstrdup(""),
+					 &item->conf);
 	}
 
 	/* Add a trailer item for each trailer on the command line */
 	for_each_string_list_item(tr, trailers) {
-		struct trailer_item *new = create_trailer_item(tr->string);
+		if (!parse_trailer(&tok, &val, &conf, tr->string))
-		add_trailer_item(arg_head, new);
+			add_trailer_item(arg_head,
+					 strbuf_detach(&tok, NULL),
+					 strbuf_detach(&val, NULL),
+					 conf);
 	}
 }
 
@@ -734,6 +719,9 @@ static int process_input_file(FILE *outfile,
 {
 	int count = 0;
 	int patch_start, trailer_start, trailer_end, i;
+	struct strbuf tok = STRBUF_INIT;
+	struct strbuf val = STRBUF_INIT;
+	const struct conf_info *conf;
 
 	/* Get the line count */
 	while (lines[count])
@@ -751,10 +739,12 @@ static int process_input_file(FILE *outfile,
 
 	/* Parse trailer lines */
 	for (i = trailer_start; i < trailer_end; i++) {
-		if (lines[i]->buf[0] != comment_line_char) {
+		if (lines[i]->buf[0] != comment_line_char &&
-			struct trailer_item *new = create_trailer_item(lines[i]->buf);
+		    !parse_trailer(&tok, &val, &conf, lines[i]->buf))
-			add_trailer_item(head, new);
+			add_trailer_item(head,
-		}
+					 strbuf_detach(&tok, NULL),
+					 strbuf_detach(&val, NULL),
+					 conf);
 	}
 
 	return trailer_end;