[PATCH 0/4] git-am: use trailers to add extra signatures

@@ -25,7 +25,7 @@ int cmd_interpret_trailers(int argc, const char **argv, const char *prefix)
 	struct option options[] = {
 		OPT_BOOL(0, "in-place", &in_place, N_("edit files in place")),
 		OPT_BOOL(0, "trim-empty", &trim_empty, N_("trim empty trailers")),
-		OPT_STRING_LIST(0, "trailer", &trailers, N_("trailer"),
+		OPT_STRING_LIST('t', "trailer", &trailers, N_("trailer"),
 				N_("trailer(s) to add")),
 		OPT_END()
 	};

@@ -2,6 +2,6 @@
 #define TRAILER_H
 
 void process_trailers(const char *file, int in_place, int trim_empty,
-		      struct string_list *trailers);
+		      int suppress_blank_line, struct string_list *trailers);
 
 #endif /* TRAILER_H */

@@ -18,11 +18,14 @@ static const char * const git_interpret_trailers_usage[] = {
 
 int cmd_interpret_trailers(int argc, const char **argv, const char *prefix)
 {
+	int suppress_blank_line = 0;
 	int in_place = 0;
 	int trim_empty = 0;
 	struct string_list trailers = STRING_LIST_INIT_DUP;
 
 	struct option options[] = {
+		OPT_BOOL(0, "suppress-blank-line", &suppress_blank_line,
+			 N_("suppress prefixing tailer(s) with a blank line ")),
 		OPT_BOOL(0, "in-place", &in_place, N_("edit files in place")),
 		OPT_BOOL(0, "trim-empty", &trim_empty, N_("trim empty trailers")),
 		OPT_STRING_LIST('t', "trailer", &trailers, N_("trailer"),

@@ -36,11 +39,13 @@ int cmd_interpret_trailers(int argc, const char **argv, const char *prefix)
 	if (argc) {
 		int i;
 		for (i = 0; i < argc; i++)
-			process_trailers(argv[i], in_place, trim_empty, &trailers);
+			process_trailers(argv[i], in_place, trim_empty,
+					 suppress_blank_line, &trailers);
 	} else {
 		if (in_place)
 			die(_("no input file given for in-place editing"));
-		process_trailers(NULL, in_place, trim_empty, &trailers);
+		process_trailers(NULL, in_place, trim_empty,
+				 suppress_blank_line, &trailers);
 	}
 
 	string_list_clear(&trailers, 0);

@@ -805,6 +805,7 @@ static void print_lines(FILE *outfile, struct strbuf **lines, int start, int end
 
 static int process_input_file(FILE *outfile,
 			      struct strbuf **lines,
+			      int suppress_blank_line,
 			      struct trailer_item **in_tok_first,
 			      struct trailer_item **in_tok_last)
 {

@@ -822,7 +823,8 @@ static int process_input_file(FILE *outfile,
 	/* Print lines before the trailers as is */
 	print_lines(outfile, lines, 0, trailer_start);
 
-	if (!has_blank_line_before(lines, trailer_start - 1))
+	if (!suppress_blank_line &&
+	    !has_blank_line_before(lines, trailer_start - 1))
 		fprintf(outfile, "\n");
 
 	/* Parse trailer lines */

@@ -875,7 +877,8 @@ static FILE *create_in_place_tempfile(const char *file)
 	return outfile;
 }
 
-void process_trailers(const char *file, int in_place, int trim_empty, struct string_list *trailers)
+void process_trailers(const char *file, int in_place, int trim_empty,
+		      int suppress_blank_line, struct string_list *trailers)
 {
 	struct trailer_item *in_tok_first = NULL;
 	struct trailer_item *in_tok_last = NULL;

@@ -894,7 +897,8 @@ void process_trailers(const char *file, int in_place, int trim_empty, struct str
 		outfile = create_in_place_tempfile(file);
 
 	/* Print the lines before the trailers */
-	trailer_end = process_input_file(outfile, lines, &in_tok_first, &in_tok_last);
+	trailer_end = process_input_file(outfile, lines, suppress_blank_line,
+					 &in_tok_first, &in_tok_last);
 
 	arg_tok_first = process_command_line_args(trailers);
 

@@ -122,6 +122,7 @@ struct am_state {
 	int message_id;
 	int scissors; /* enum scissors_type */
 	struct argv_array git_apply_opts;
+	struct argv_array git_interpret_trailers_opts;
 	const char *resolvemsg;
 	int committer_date_is_author_date;
 	int ignore_date;

@@ -157,6 +158,8 @@ static void am_state_init(struct am_state *state, const char *dir)
 
 	if (!git_config_get_bool("commit.gpgsign", &gpgsign))
 		state->sign_commit = gpgsign ? "" : NULL;
+
+	argv_array_init(&state->git_interpret_trailers_opts);
 }
 
 /**

@@ -170,6 +173,7 @@ static void am_state_release(struct am_state *state)
 	free(state->author_date);
 	free(state->msg);
 	argv_array_clear(&state->git_apply_opts);
+	argv_array_clear(&state->git_interpret_trailers_opts);
 }
 
 /**

@@ -472,6 +476,11 @@ static void am_load(struct am_state *state)
 	if (sq_dequote_to_argv_array(sb.buf, &state->git_apply_opts) < 0)
 		die(_("could not parse %s"), am_path(state, "apply-opt"));
 
+	read_state_file(&sb, state, "interpret-trailers-opt", 1);
+	argv_array_clear(&state->git_interpret_trailers_opts);
+	if (sq_dequote_to_argv_array(sb.buf, &state->git_interpret_trailers_opts) < 0)
+		die(_("could not parse %s"), am_path(state, "interpret-trailers-opt"));
+
 	state->rebasing = !!file_exists(am_path(state, "rebasing"));
 
 	strbuf_release(&sb);

@@ -988,6 +997,7 @@ static void am_setup(struct am_state *state, enum patch_format patch_format,
 	unsigned char curr_head[GIT_SHA1_RAWSZ];
 	const char *str;
 	struct strbuf sb = STRBUF_INIT;
+	struct strbuf tsb = STRBUF_INIT;
 
 	if (!patch_format)
 		patch_format = detect_patch_format(paths);

@@ -1048,6 +1058,9 @@ static void am_setup(struct am_state *state, enum patch_format patch_format,
 	sq_quote_argv(&sb, state->git_apply_opts.argv, 0);
 	write_state_text(state, "apply-opt", sb.buf);
 
+	sq_quote_argv(&tsb, state->git_interpret_trailers_opts.argv, 0);
+	write_state_text(state, "interpret-trailers-opt", tsb.buf);
+
 	if (state->rebasing)
 		write_state_text(state, "rebasing", "");
 	else

@@ -1072,6 +1085,7 @@ static void am_setup(struct am_state *state, enum patch_format patch_format,
 	write_state_count(state, "next", state->cur);
 	write_state_count(state, "last", state->last);
 
+	strbuf_release(&tsb);
 	strbuf_release(&sb);
 }
 

@@ -1233,6 +1247,34 @@ static void am_append_signoff(struct am_state *state)
 }
 
 /**
+ * Processes the supplied message file in-place with git-interpret-trailers.
+ * Returns 0 on success, -1 otherwise.
+ */
+static int run_interpret_trailers(const struct am_state *state, const char *msg)
+{
+	struct child_process cp = CHILD_PROCESS_INIT;
+
+	if (!state->git_interpret_trailers_opts.argc)
+		return 0;
+
+	cp.git_cmd = 1;
+
+	argv_array_push(&cp.args, "interpret-trailers");
+
+	argv_array_push(&cp.args, "--in-place");
+	argv_array_push(&cp.args, "--suppress-blank-line");
+
+	argv_array_pushv(&cp.args, state->git_interpret_trailers_opts.argv);
+
+	argv_array_push(&cp.args, msg);
+
+	if (run_command(&cp))
+		return -1;
+
+	return 0;
+}
+
+/**
  * Parses `mail` using git-mailinfo, extracting its patch and authorship info.
  * state->msg will be set to the patch message. state->author_name,
  * state->author_email and state->author_date will be set to the patch author's

@@ -1301,6 +1343,9 @@ static int parse_mail(struct am_state *state, const char *mail)
 	fclose(mi.input);
 	fclose(mi.output);
 
+	if (run_interpret_trailers(state, am_path(state, "msg")) < 0)
+		die("could not interpret trailers");
+
 	/* Extract message and author information */
 	fp = xfopen(am_path(state, "info"), "r");
 	while (!strbuf_getline_lf(&sb, fp)) {

@@ -2299,6 +2344,9 @@ int cmd_am(int argc, const char **argv, const char *prefix)
 		OPT_PASSTHRU_ARGV('p', NULL, &state.git_apply_opts, N_("num"),
 			N_("pass it through git-apply"),
 			0),
+		OPT_PASSTHRU_ARGV('t', "trailer", &state.git_interpret_trailers_opts, N_("trailer"),
+			N_("pass it through git-interpret-trailers"),
+			0),
 		OPT_CALLBACK(0, "patch-format", &patch_format, N_("format"),
 			N_("format the patch(es) are in"),
 			parse_opt_patchformat),

@@ -1246,6 +1246,7 @@ static int parse_mail(struct am_state *state, const char *mail)
 	FILE *fp;
 	struct strbuf sb = STRBUF_INIT;
 	struct strbuf msg = STRBUF_INIT;
+	struct strbuf log_msg = STRBUF_INIT;
 	struct strbuf author_name = STRBUF_INIT;
 	struct strbuf author_date = STRBUF_INIT;
 	struct strbuf author_email = STRBUF_INIT;

@@ -1330,7 +1331,12 @@ static int parse_mail(struct am_state *state, const char *mail)
 	}
 
 	strbuf_addstr(&msg, "\n\n");
-	strbuf_addbuf(&msg, &mi.log_message);
+
+	if (strbuf_read_file(&log_msg,  am_path(state, "msg"), 0) < 0) {
+		die_errno(_("could not read '%s'"), am_path(state, "msg"));
+	}
+
+	strbuf_addbuf(&msg, &log_msg);
 	strbuf_stripspace(&msg, 0);
 
 	if (state->signoff)

@@ -1349,6 +1355,7 @@ static int parse_mail(struct am_state *state, const char *mail)
 	state->msg = strbuf_detach(&msg, &state->msg_len);
 
 finish:
+	strbuf_release(&log_msg);
 	strbuf_release(&msg);
 	strbuf_release(&author_date);
 	strbuf_release(&author_email);