[src/trunk]: src/sys/dev/stbi reduce stack usage of stbi_gif_load_from_memory...

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

details:   https://anonhg.NetBSD.org/src/rev/cf6672d804f4
branches:  trunk
changeset: 772902:cf6672d804f4
user:      jmcneill <jmcneill%NetBSD.org@localhost>
date:      Fri Jan 20 23:13:47 2012 +0000

description:
reduce stack usage of stbi_gif_load_from_memory when STBI_SMALL_STACK is
defined

diffstat:

 sys/dev/stbi/stb_image.c |  26 ++++++++++++++++++++------
 1 files changed, 20 insertions(+), 6 deletions(-)

diffs (48 lines):

diff -r dc6e8c5dacf2 -r cf6672d804f4 sys/dev/stbi/stb_image.c
--- a/sys/dev/stbi/stb_image.c  Fri Jan 20 23:01:05 2012 +0000
+++ b/sys/dev/stbi/stb_image.c  Fri Jan 20 23:13:47 2012 +0000
@@ -430,7 +430,7 @@
 #endif
 #ifdef _KERNEL
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: stb_image.c,v 1.1 2011/02/06 23:13:04 jmcneill Exp $");
+__KERNEL_RCSID(0, "$NetBSD: stb_image.c,v 1.2 2012/01/20 23:13:47 jmcneill Exp $");
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/kernel.h>
@@ -4601,16 +4601,30 @@
 {
    uint8 *u = 0;
    stbi s;
+   stbi_gif *pg;
+
+   #ifdef STBI_SMALL_STACK
+   pg = (stbi_gif *) MALLOC(sizeof(*pg));
+   if (pg == NULL)
+      return NULL;
+   #else
    stbi_gif g;
-
-   memset(&g, 0, sizeof(g));
+   pg = &g;
+   #endif
+
+   memset(pg, 0, sizeof(*pg));
    start_mem(&s, buffer, len);
-   u = stbi_gif_load_next(&s, &g, comp, req_comp);
+   u = stbi_gif_load_next(&s, pg, comp, req_comp);
    if (u == (void *) 1) u = 0;  // end of animated gif marker
    if (u) {
-      *x = g.w;
-      *y = g.h;
+      *x = pg->w;
+      *y = pg->h;
    }
+
+   #ifdef STBI_SMALL_STACK
+   FREE(pg);
+   #endif
+
    return u;
 }