Mechanical conversion to use prefixcmp()

This mechanically converts strncmp() to use prefixcmp(), but only when
the parameters match specific patterns, so that they can be verified
easily.  Leftover from this will be fixed in a separate step, including
idiotic conversions like

    if (!strncmp("foo", arg, 3))

  =>

    if (!(-prefixcmp(arg, "foo")))

This was done by using this script in px.perl

   #!/usr/bin/perl -i.bak -p
   if (/strncmp\(([^,]+), "([^\\"]*)", (\d+)\)/ && (length($2) == $3)) {
           s|strncmp\(([^,]+), "([^\\"]*)", (\d+)\)|prefixcmp($1, "$2")|;
   }
   if (/strncmp\("([^\\"]*)", ([^,]+), (\d+)\)/ && (length($1) == $3)) {
           s|strncmp\("([^\\"]*)", ([^,]+), (\d+)\)|(-prefixcmp($2, "$1"))|;
   }

and running:

   $ git grep -l strncmp -- '*.c' | xargs perl px.perl

Signed-off-by: Junio C Hamano <junkio@cox.net>

1 files changed, 3 insertions, 3 deletions

diff --git a/builtin-shortlog.c b/builtin-shortlog.c
index edb4042..2f71a2a 100644
--- a/builtin-shortlog.c
+++ b/builtin-shortlog.c
@@ -124,7 +124,7 @@ static void insert_author_oneline(struct path_list *list,
 	else
 		free(buffer);
 
-	if (!strncmp(oneline, "[PATCH", 6)) {
+	if (!prefixcmp(oneline, "[PATCH")) {
 		char *eob = strchr(oneline, ']');
 
 		if (eob) {
@@ -179,7 +179,7 @@ static void read_from_stdin(struct path_list *list)
 	while (fgets(buffer, sizeof(buffer), stdin) != NULL) {
 		char *bob;
 		if ((buffer[0] == 'A' || buffer[0] == 'a') &&
-				!strncmp(buffer + 1, "uthor: ", 7) &&
+				!prefixcmp(buffer + 1, "uthor: ") &&
 				(bob = strchr(buffer + 7, '<')) != NULL) {
 			char buffer2[1024], offset = 0;
 
@@ -230,7 +230,7 @@ static void get_from_rev(struct rev_info *rev, struct path_list *list)
 			else
 				eol++;
 
-			if (!strncmp(buffer, "author ", 7)) {
+			if (!prefixcmp(buffer, "author ")) {
 				char *bracket = strchr(buffer, '<');
 
 				if (bracket == NULL || bracket > eol)