From 7e741ffc1e78c2ec9dfe8725f8fa52ca8bc393cc Mon Sep 17 00:00:00 2001
From: Romain Bailly <rom175-github@yahoo.com>
Date: Thu, 14 Jan 2016 10:34:30 +0100
Subject: [PATCH] Added the old size as argument to the STBI_REALLOC() and
 STBIW_REALLOC() macros

---
 stb_image.h       | 15 ++++++++-------
 stb_image_write.h |  8 ++++----
 2 files changed, 12 insertions(+), 11 deletions(-)

diff --git a/stb_image.h b/stb_image.h
index 0a9de39..fcb574f 100644
--- a/stb_image.h
+++ b/stb_image.h
@@ -639,9 +639,9 @@ typedef unsigned char validate_uint32[sizeof(stbi__uint32)==4 ? 1 : -1];
 #endif
 
 #ifndef STBI_MALLOC
-#define STBI_MALLOC(sz)    malloc(sz)
-#define STBI_REALLOC(p,sz) realloc(p,sz)
-#define STBI_FREE(p)       free(p)
+#define STBI_MALLOC(sz)             malloc(sz)
+#define STBI_REALLOC(p,oldsz,newsz) realloc(p,newsz)
+#define STBI_FREE(p)                free(p)
 #endif
 
 // x86/x64 detection
@@ -3616,14 +3616,14 @@ stbi_inline static int stbi__zhuffman_decode(stbi__zbuf *a, stbi__zhuffman *z)
 static int stbi__zexpand(stbi__zbuf *z, char *zout, int n)  // need to make room for n bytes
 {
    char *q;
-   int cur, limit;
+   int cur, limit, old_limit;
    z->zout = zout;
    if (!z->z_expandable) return stbi__err("output buffer limit","Corrupt PNG");
    cur   = (int) (z->zout     - z->zout_start);
-   limit = (int) (z->zout_end - z->zout_start);
+   limit = old_limit = (int) (z->zout_end - z->zout_start);
    while (cur + n > limit)
       limit *= 2;
-   q = (char *) STBI_REALLOC(z->zout_start, limit);
+   q = (char *) STBI_REALLOC(z->zout_start, old_limit, limit);
    if (q == NULL) return stbi__err("outofmem", "Out of memory");
    z->zout_start = q;
    z->zout       = q + cur;
@@ -4408,11 +4408,12 @@ static int stbi__parse_png_file(stbi__png *z, int scan, int req_comp)
             if (scan == STBI__SCAN_header) { s->img_n = pal_img_n; return 1; }
             if ((int)(ioff + c.length) < (int)ioff) return 0;
             if (ioff + c.length > idata_limit) {
+               stbi__uint32 idata_limit_old = idata_limit;
                stbi_uc *p;
                if (idata_limit == 0) idata_limit = c.length > 4096 ? c.length : 4096;
                while (ioff + c.length > idata_limit)
                   idata_limit *= 2;
-               p = (stbi_uc *) STBI_REALLOC(z->idata, idata_limit); if (p == NULL) return stbi__err("outofmem", "Out of memory");
+               p = (stbi_uc *) STBI_REALLOC(z->idata, idata_limit_old, idata_limit); if (p == NULL) return stbi__err("outofmem", "Out of memory");
                z->idata = p;
             }
             if (!stbi__getn(s, z->idata+ioff,c.length)) return stbi__err("outofdata","Corrupt PNG");
diff --git a/stb_image_write.h b/stb_image_write.h
index 38d3835..c737bb4 100644
--- a/stb_image_write.h
+++ b/stb_image_write.h
@@ -166,9 +166,9 @@ STBIWDEF int stbi_write_hdr_to_func(stbi_write_func *func, void *context, int w,
 #endif
 
 #ifndef STBIW_MALLOC
-#define STBIW_MALLOC(sz)    malloc(sz)
-#define STBIW_REALLOC(p,sz) realloc(p,sz)
-#define STBIW_FREE(p)       free(p)
+#define STBIW_MALLOC(sz)             malloc(sz)
+#define STBIW_REALLOC(p,oldsz,newsz) realloc(p,newsz)
+#define STBIW_FREE(p)                free(p)
 #endif
 #ifndef STBIW_MEMMOVE
 #define STBIW_MEMMOVE(a,b,sz) memmove(a,b,sz)
@@ -647,7 +647,7 @@ int stbi_write_hdr(char const *filename, int x, int y, int comp, const float *da
 static void *stbiw__sbgrowf(void **arr, int increment, int itemsize)
 {
    int m = *arr ? 2*stbiw__sbm(*arr)+increment : increment+1;
-   void *p = STBIW_REALLOC(*arr ? stbiw__sbraw(*arr) : 0, itemsize * m + sizeof(int)*2);
+   void *p = STBIW_REALLOC(*arr ? stbiw__sbraw(*arr) : 0, *arr ? (stbiw__sbm(*arr)*itemsize + sizeof(int)*2) : 0, itemsize * m + sizeof(int)*2);
    STBIW_ASSERT(p);
    if (p) {
       if (!*arr) ((int *) p)[1] = 0;