Merge branch 'jk/pretty-subject-cleanup'

Code clean-up in the "git log" machinery that implements custom log
message formatting.

* jk/pretty-subject-cleanup:
  format-patch: fix leak of empty header string
  format-patch: simplify after-subject MIME header handling
  format-patch: return an allocated string from log_write_email_headers()
  log: do not set up extra_headers for non-email formats
  pretty: drop print_email_subject flag
  pretty: split oneline and email subject printing
  shortlog: stop setting pp.print_email_subject

7 files changed, 38 insertions, 46 deletions

diff --git a/builtin/log.c b/builtin/log.c
index e5da0d1043..c0a8bb95e9 100644
--- a/builtin/log.c
+++ b/builtin/log.c
@@ -1297,7 +1297,7 @@ static void prepare_cover_text(struct pretty_print_context *pp,
 		subject = subject_sb.buf;
 
 do_pp:
-	pp_title_line(pp, &subject, sb, encoding, need_8bit_cte);
+	pp_email_subject(pp, &subject, sb, encoding, need_8bit_cte);
 	pp_remainder(pp, &body, sb, 0);
 
 	strbuf_release(&description_sb);
@@ -1364,13 +1364,13 @@ static void make_cover_letter(struct rev_info *rev, int use_separate_file,
 	pp.fmt = CMIT_FMT_EMAIL;
 	pp.date_mode.type = DATE_RFC2822;
 	pp.rev = rev;
-	pp.print_email_subject = 1;
 	pp.encode_email_headers = rev->encode_email_headers;
 	pp_user_info(&pp, NULL, &sb, committer, encoding);
 	prepare_cover_text(&pp, description_file, branch_name, &sb,
 			   encoding, need_8bit_cte);
 	fprintf(rev->diffopt.file, "%s\n", sb.buf);
 
+	free(pp.after_subject);
 	strbuf_release(&sb);
 
 	shortlog_init(&log);
diff --git a/builtin/rev-list.c b/builtin/rev-list.c
index ec455aa972..77803727e0 100644
--- a/builtin/rev-list.c
+++ b/builtin/rev-list.c
@@ -219,6 +219,7 @@ static void show_commit(struct commit *commit, void *data)
 		ctx.fmt = revs->commit_format;
 		ctx.output_encoding = get_log_output_encoding();
 		ctx.color = revs->diffopt.use_color;
+		ctx.rev = revs;
 		pretty_print_commit(&ctx, commit, &buf);
 		if (buf.len) {
 			if (revs->commit_format != CMIT_FMT_ONELINE)
diff --git a/builtin/shortlog.c b/builtin/shortlog.c
index 1307ed2b88..3c7cd2d6ef 100644
--- a/builtin/shortlog.c
+++ b/builtin/shortlog.c
@@ -245,7 +245,6 @@ void shortlog_add_commit(struct shortlog *log, struct commit *commit)
 
 	ctx.fmt = CMIT_FMT_USERFORMAT;
 	ctx.abbrev = log->abbrev;
-	ctx.print_email_subject = 1;
 	ctx.date_mode = log->date_mode;
 	ctx.output_encoding = get_log_output_encoding();
 
diff --git a/log-tree.c b/log-tree.c
index e5438b029d..59eeaef1f7 100644
--- a/log-tree.c
+++ b/log-tree.c
@@ -470,16 +470,19 @@ void fmt_output_email_subject(struct strbuf *sb, struct rev_info *opt)
 }
 
 void log_write_email_headers(struct rev_info *opt, struct commit *commit,
-			     const char **extra_headers_p,
+			     char **extra_headers_p,
 			     int *need_8bit_cte_p,
 			     int maybe_multipart)
 {
-	const char *extra_headers = opt->extra_headers;
+	struct strbuf headers = STRBUF_INIT;
 	const char *name = oid_to_hex(opt->zero_commit ?
 				      null_oid() : &commit->object.oid);
 
 	*need_8bit_cte_p = 0; /* unknown */
 
+	if (opt->extra_headers && *opt->extra_headers)
+		strbuf_addstr(&headers, opt->extra_headers);
+
 	fprintf(opt->diffopt.file, "From %s Mon Sep 17 00:00:00 2001\n", name);
 	graph_show_oneline(opt->graph);
 	if (opt->message_id) {
@@ -496,16 +499,13 @@ void log_write_email_headers(struct rev_info *opt, struct commit *commit,
 		graph_show_oneline(opt->graph);
 	}
 	if (opt->mime_boundary && maybe_multipart) {
-		static struct strbuf subject_buffer = STRBUF_INIT;
 		static struct strbuf buffer = STRBUF_INIT;
 		struct strbuf filename =  STRBUF_INIT;
 		*need_8bit_cte_p = -1; /* NEVER */
 
-		strbuf_reset(&subject_buffer);
 		strbuf_reset(&buffer);
 
-		strbuf_addf(&subject_buffer,
-			 "%s"
+		strbuf_addf(&headers,
 			 "MIME-Version: 1.0\n"
 			 "Content-Type: multipart/mixed;"
 			 " boundary=\"%s%s\"\n"
@@ -516,10 +516,8 @@ void log_write_email_headers(struct rev_info *opt, struct commit *commit,
 			 "Content-Type: text/plain; "
 			 "charset=UTF-8; format=fixed\n"
 			 "Content-Transfer-Encoding: 8bit\n\n",
-			 extra_headers ? extra_headers : "",
 			 mime_boundary_leader, opt->mime_boundary,
 			 mime_boundary_leader, opt->mime_boundary);
-		extra_headers = subject_buffer.buf;
 
 		if (opt->numbered_files)
 			strbuf_addf(&filename, "%d", opt->nr);
@@ -539,7 +537,7 @@ void log_write_email_headers(struct rev_info *opt, struct commit *commit,
 		opt->diffopt.stat_sep = buffer.buf;
 		strbuf_release(&filename);
 	}
-	*extra_headers_p = extra_headers;
+	*extra_headers_p = headers.len ? strbuf_detach(&headers, NULL) : NULL;
 }
 
 static void show_sig_lines(struct rev_info *opt, int status, const char *bol)
@@ -678,7 +676,6 @@ void show_log(struct rev_info *opt)
 	struct log_info *log = opt->loginfo;
 	struct commit *commit = log->commit, *parent = log->parent;
 	int abbrev_commit = opt->abbrev_commit ? opt->abbrev : the_hash_algo->hexsz;
-	const char *extra_headers = opt->extra_headers;
 	struct pretty_print_context ctx = {0};
 
 	opt->loginfo = NULL;
@@ -739,10 +736,9 @@ void show_log(struct rev_info *opt)
 	 */
 
 	if (cmit_fmt_is_mail(opt->commit_format)) {
-		log_write_email_headers(opt, commit, &extra_headers,
+		log_write_email_headers(opt, commit, &ctx.after_subject,
 					&ctx.need_8bit_cte, 1);
 		ctx.rev = opt;
-		ctx.print_email_subject = 1;
 	} else if (opt->commit_format != CMIT_FMT_USERFORMAT) {
 		fputs(diff_get_color_opt(&opt->diffopt, DIFF_COMMIT), opt->diffopt.file);
 		if (opt->commit_format != CMIT_FMT_ONELINE)
@@ -808,7 +804,6 @@ void show_log(struct rev_info *opt)
 	ctx.date_mode = opt->date_mode;
 	ctx.date_mode_explicit = opt->date_mode_explicit;
 	ctx.abbrev = opt->diffopt.abbrev;
-	ctx.after_subject = extra_headers;
 	ctx.preserve_subject = opt->preserve_subject;
 	ctx.encode_email_headers = opt->encode_email_headers;
 	ctx.reflog_info = opt->reflog_info;
@@ -857,6 +852,7 @@ void show_log(struct rev_info *opt)
 
 	strbuf_release(&msgbuf);
 	free(ctx.notes_message);
+	free(ctx.after_subject);
 
 	if (cmit_fmt_is_mail(ctx.fmt) && opt->idiff_oid1) {
 		struct diff_queue_struct dq;
diff --git a/log-tree.h b/log-tree.h
index 41c776fea5..94978e2c83 100644
--- a/log-tree.h
+++ b/log-tree.h
@@ -29,7 +29,7 @@ void format_decorations(struct strbuf *sb, const struct commit *commit,
 			int use_color, const struct decoration_options *opts);
 void show_decorations(struct rev_info *opt, struct commit *commit);
 void log_write_email_headers(struct rev_info *opt, struct commit *commit,
-			     const char **extra_headers_p,
+			     char **extra_headers_p,
 			     int *need_8bit_cte_p,
 			     int maybe_multipart);
 void load_ref_decorations(struct decoration_filter *filter, int flags);
diff --git a/pretty.c b/pretty.c
index bdbed4295a..eecbce82cf 100644
--- a/pretty.c
+++ b/pretty.c
@@ -2077,11 +2077,11 @@ static void pp_header(struct pretty_print_context *pp,
 	}
 }
 
-void pp_title_line(struct pretty_print_context *pp,
-		   const char **msg_p,
-		   struct strbuf *sb,
-		   const char *encoding,
-		   int need_8bit_cte)
+void pp_email_subject(struct pretty_print_context *pp,
+		      const char **msg_p,
+		      struct strbuf *sb,
+		      const char *encoding,
+		      int need_8bit_cte)
 {
 	static const int max_length = 78; /* per rfc2047 */
 	struct strbuf title;
@@ -2091,19 +2091,14 @@ void pp_title_line(struct pretty_print_context *pp,
 				pp->preserve_subject ? "\n" : " ");
 
 	strbuf_grow(sb, title.len + 1024);
-	if (pp->print_email_subject) {
-		if (pp->rev)
-			fmt_output_email_subject(sb, pp->rev);
-		if (pp->encode_email_headers &&
-		    needs_rfc2047_encoding(title.buf, title.len))
-			add_rfc2047(sb, title.buf, title.len,
-						encoding, RFC2047_SUBJECT);
-		else
-			strbuf_add_wrapped_bytes(sb, title.buf, title.len,
+	fmt_output_email_subject(sb, pp->rev);
+	if (pp->encode_email_headers &&
+	    needs_rfc2047_encoding(title.buf, title.len))
+		add_rfc2047(sb, title.buf, title.len,
+			    encoding, RFC2047_SUBJECT);
+	else
+		strbuf_add_wrapped_bytes(sb, title.buf, title.len,
 					 -last_line_length(sb), 1, max_length);
-	} else {
-		strbuf_addbuf(sb, &title);
-	}
 	strbuf_addch(sb, '\n');
 
 	if (need_8bit_cte == 0) {
@@ -2126,9 +2121,8 @@ void pp_title_line(struct pretty_print_context *pp,
 	if (pp->after_subject) {
 		strbuf_addstr(sb, pp->after_subject);
 	}
-	if (cmit_fmt_is_mail(pp->fmt)) {
-		strbuf_addch(sb, '\n');
-	}
+
+	strbuf_addch(sb, '\n');
 
 	if (pp->in_body_headers.nr) {
 		int i;
@@ -2320,7 +2314,7 @@ void pretty_print_commit(struct pretty_print_context *pp,
 	}
 
 	pp_header(pp, encoding, commit, &msg, sb);
-	if (pp->fmt != CMIT_FMT_ONELINE && !pp->print_email_subject) {
+	if (pp->fmt != CMIT_FMT_ONELINE && !cmit_fmt_is_mail(pp->fmt)) {
 		strbuf_addch(sb, '\n');
 	}
 
@@ -2328,8 +2322,11 @@ void pretty_print_commit(struct pretty_print_context *pp,
 	msg = skip_blank_lines(msg);
 
 	/* These formats treat the title line specially. */
-	if (pp->fmt == CMIT_FMT_ONELINE || cmit_fmt_is_mail(pp->fmt))
-		pp_title_line(pp, &msg, sb, encoding, need_8bit_cte);
+	if (pp->fmt == CMIT_FMT_ONELINE) {
+		msg = format_subject(sb, msg, " ");
+		strbuf_addch(sb, '\n');
+	} else if (cmit_fmt_is_mail(pp->fmt))
+		pp_email_subject(pp, &msg, sb, encoding, need_8bit_cte);
 
 	beginning_of_body = sb->len;
 	if (pp->fmt != CMIT_FMT_ONELINE)
diff --git a/pretty.h b/pretty.h
index 421209e9ec..9cc9e5d42b 100644
--- a/pretty.h
+++ b/pretty.h
@@ -35,11 +35,10 @@ struct pretty_print_context {
 	 */
 	enum cmit_fmt fmt;
 	int abbrev;
-	const char *after_subject;
+	char *after_subject;
 	int preserve_subject;
 	struct date_mode date_mode;
 	unsigned date_mode_explicit:1;
-	int print_email_subject;
 	int expand_tabs_in_log;
 	int need_8bit_cte;
 	char *notes_message;
@@ -96,13 +95,13 @@ void pp_user_info(struct pretty_print_context *pp, const char *what,
 			const char *encoding);
 
 /*
- * Format title line of commit message taken from "msg_p" and
+ * Format subject line of commit message taken from "msg_p" and
  * put it into "sb".
  * First line of "msg_p" is also affected.
  */
-void pp_title_line(struct pretty_print_context *pp, const char **msg_p,
-			struct strbuf *sb, const char *encoding,
-			int need_8bit_cte);
+void pp_email_subject(struct pretty_print_context *pp, const char **msg_p,
+		      struct strbuf *sb, const char *encoding,
+		      int need_8bit_cte);
 
 /*
  * Get current state of commit message from "msg_p" and continue formatting