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, 5 insertions, 5 deletions

diff --git a/upload-pack.c b/upload-pack.c
index 3648aae1a7..d7876cade9 100644
--- a/upload-pack.c
+++ b/upload-pack.c
@@ -455,7 +455,7 @@ static int get_common_commits(void)
 			continue;
 		}
 		len = strip(line, len);
-		if (!strncmp(line, "have ", 5)) {
+		if (!prefixcmp(line, "have ")) {
 			switch (got_sha1(line+5, sha1)) {
 			case -1: /* they have what we do not */
 				if (multi_ack && ok_to_give_up())
@@ -502,7 +502,7 @@ static void receive_needs(void)
 		if (!len)
 			break;
 
-		if (!strncmp("shallow ", line, 8)) {
+		if (!(-prefixcmp(line, "shallow "))) {
 			unsigned char sha1[20];
 			struct object *object;
 			use_thin_pack = 0;
@@ -515,7 +515,7 @@ static void receive_needs(void)
 			add_object_array(object, NULL, &shallows);
 			continue;
 		}
-		if (!strncmp("deepen ", line, 7)) {
+		if (!(-prefixcmp(line, "deepen "))) {
 			char *end;
 			use_thin_pack = 0;
 			depth = strtol(line + 7, &end, 0);
@@ -523,7 +523,7 @@ static void receive_needs(void)
 				die("Invalid deepen: %s", line);
 			continue;
 		}
-		if (strncmp("want ", line, 5) ||
+		if ((-prefixcmp(line, "want ")) ||
 		    get_sha1_hex(line+5, sha1_buf))
 			die("git-upload-pack: protocol error, "
 			    "expected to get sha, not '%s'", line);
@@ -656,7 +656,7 @@ int main(int argc, char **argv)
 			strict = 1;
 			continue;
 		}
-		if (!strncmp(arg, "--timeout=", 10)) {
+		if (!prefixcmp(arg, "--timeout=")) {
 			timeout = atoi(arg+10);
 			continue;
 		}