[src/trunk]: src/usr.bin/make Reduce the calls to realloc from brk_string by ...

[sjg <sjg%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/a3b2363d51ac
branches:  trunk
changeset: 326676:a3b2363d51ac
user:      sjg <sjg%NetBSD.org@localhost>
date:      Wed Feb 12 01:35:56 2014 +0000

description:
Reduce the calls to realloc from brk_string by basing initial argmax guess
on length of input.

Reviewed by: christos

diffstat:

 usr.bin/make/str.c |  14 ++++++++++----
 1 files changed, 10 insertions(+), 4 deletions(-)

diffs (48 lines):

diff -r ac1cc5aa2fb0 -r a3b2363d51ac usr.bin/make/str.c
--- a/usr.bin/make/str.c        Tue Feb 11 22:48:25 2014 +0000
+++ b/usr.bin/make/str.c        Wed Feb 12 01:35:56 2014 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: str.c,v 1.34 2012/03/03 23:16:47 dholland Exp $        */
+/*     $NetBSD: str.c,v 1.35 2014/02/12 01:35:56 sjg Exp $     */
 
 /*-
  * Copyright (c) 1988, 1989, 1990, 1993
@@ -69,14 +69,14 @@
  */
 
 #ifndef MAKE_NATIVE
-static char rcsid[] = "$NetBSD: str.c,v 1.34 2012/03/03 23:16:47 dholland Exp $";
+static char rcsid[] = "$NetBSD: str.c,v 1.35 2014/02/12 01:35:56 sjg Exp $";
 #else
 #include <sys/cdefs.h>
 #ifndef lint
 #if 0
 static char     sccsid[] = "@(#)str.c  5.8 (Berkeley) 6/1/90";
 #else
-__RCSID("$NetBSD: str.c,v 1.34 2012/03/03 23:16:47 dholland Exp $");
+__RCSID("$NetBSD: str.c,v 1.35 2014/02/12 01:35:56 sjg Exp $");
 #endif
 #endif                         /* not lint */
 #endif
@@ -145,7 +145,7 @@
        const char *p;
        int len;
        int argmax = 50, curlen = 0;
-       char **argv = bmake_malloc((argmax + 1) * sizeof(char *));
+       char **argv;
 
        /* skip leading space chars. */
        for (; *str == ' ' || *str == '\t'; ++str)
@@ -156,6 +156,12 @@
                *buffer = bmake_malloc(curlen = len);
 
        /*
+        * initial argmax based on len
+        */
+       argmax = MAX((len / 5), 50);
+       argv = bmake_malloc((argmax + 1) * sizeof(char *));
+
+       /*
         * copy the string; at the same time, parse backslashes,
         * quotes and build the argument list.
         */