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-for-each-ref.c b/builtin-for-each-ref.c
index 16c785f04..ac0b9f608 100644
--- a/builtin-for-each-ref.c
+++ b/builtin-for-each-ref.c
@@ -814,7 +814,7 @@ int cmd_for_each_ref(int ac, const char **av, char *prefix)
 			i++;
 			break;
 		}
-		if (!strncmp(arg, "--format=", 9)) {
+		if (!prefixcmp(arg, "--format=")) {
 			if (format)
 				die("more than one --format?");
 			format = arg + 9;
@@ -844,7 +844,7 @@ int cmd_for_each_ref(int ac, const char **av, char *prefix)
 			quote_style = QUOTE_TCL;
 			continue;
 		}
-		if (!strncmp(arg, "--count=", 8)) {
+		if (!prefixcmp(arg, "--count=")) {
 			if (maxcount)
 				die("more than one --count?");
 			maxcount = atoi(arg + 8);
@@ -852,7 +852,7 @@ int cmd_for_each_ref(int ac, const char **av, char *prefix)
 				die("The number %s did not parse", arg);
 			continue;
 		}
-		if (!strncmp(arg, "--sort=", 7)) {
+		if (!prefixcmp(arg, "--sort=")) {
 			struct ref_sort *s = xcalloc(1, sizeof(*s));
 			int len;