get_patch_filename(): simplify function signature

Most functions that emit to a strbuf take the strbuf as their first
parameter; make this function follow suit.

The serial number of the patch being emitted (nr) and suffix used
for patch filename (suffix) are both recorded in rev_info; drop
these separate parameters and pass the rev_info directly.

Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/log.c

diff --git a/builtin/log.c b/builtin/log.c
index 7cf157e..d9946ec 100644
--- a/builtin/log.c
+++ b/builtin/log.c
@@ -684,7 +684,7 @@
 			strbuf_addch(&filename, '/');
 	}
 
-	get_patch_filename(commit, subject, rev->nr, rev->patch_suffix, &filename);
+	get_patch_filename(&filename, commit, subject, rev);
 
 	if (!quiet)
 		fprintf(realstdout, "%s\n", filename.buf + outdir_offset);

log-tree.c

diff --git a/log-tree.c b/log-tree.c
index c894930..ceed6b6 100644
--- a/log-tree.c
+++ b/log-tree.c
@@ -299,9 +299,12 @@
 	return result;
 }
 
-void get_patch_filename(struct commit *commit, const char *subject, int nr,
-			const char *suffix, struct strbuf *buf)
+void get_patch_filename(struct strbuf *buf,
+			struct commit *commit, const char *subject,
+			struct rev_info *info)
 {
+	const char *suffix = info->patch_suffix;
+	int nr = info->nr;
 	int suffix_len = strlen(suffix) + 1;
 	int start_len = buf->len;
 
@@ -387,8 +390,9 @@
 			 mime_boundary_leader, opt->mime_boundary);
 		extra_headers = subject_buffer;
 
-		get_patch_filename(opt->numbered_files ? NULL : commit, NULL,
-				   opt->nr, opt->patch_suffix, &filename);
+		get_patch_filename(&filename,
+				   opt->numbered_files ? NULL : commit, NULL,
+				   opt);
 		snprintf(buffer, sizeof(buffer) - 1,
 			 "\n--%s%s\n"
 			 "Content-Type: text/x-patch;"

log-tree.h

diff --git a/log-tree.h b/log-tree.h
index f5ac238..c6a944a 100644
--- a/log-tree.h
+++ b/log-tree.h
@@ -21,7 +21,8 @@
 void load_ref_decorations(int flags);
 
 #define FORMAT_PATCH_NAME_MAX 64
-void get_patch_filename(struct commit *commit, const char *subject, int nr,
-			const char *suffix, struct strbuf *buf);
+void get_patch_filename(struct strbuf *buf,
+			struct commit *commit, const char *subject,
+			struct rev_info *);
 
 #endif