From fb10f363f532fe963bb7cf50b794ae06f7ae2f17 Mon Sep 17 00:00:00 2001
From: Simon McVittie <smcv@debian.org>
Date: Sat, 21 Jan 2012 22:23:03 +0000
Subject: [PATCH] If linking libpng normally, use its header to get the
png_uint_32 type
This avoids needing to work around ABI differences, particularly in
newer versions of libpng: if we know which version we're using, it's
all simpler.
Origin: vendor, Debian
---
image_png.c | 24 ++++++++++++++++++++----
1 file changed, 20 insertions(+), 4 deletions(-)
diff --git a/image_png.c b/image_png.c
index 5c9d0571..65047ef6 100644
--- a/image_png.c
+++ b/image_png.c
@@ -82,6 +82,16 @@ my_setjmp (jmp_buf env)
#else
+/*
+ * Without LINK_TO_PNG, DarkPlaces assumes libpng 1.2 (in which png_uint_32
+ * is always unsigned long even if that's 64-bit), and then attempts
+ * to correct for it if it's actually 1.4 or 1.5 (where png_uint_32 is
+ * unsigned int if that's at least 32 bits, or unsigned long otherwise).
+ *
+ * With LINK_TO_PNG we use the library API/ABI as intended.
+ */
+typedef unsigned long png_uint_32;
+
typedef void *png_structp;
typedef void **png_structpp;
typedef void *png_infop;
@@ -100,7 +110,7 @@ static void (*qpng_set_palette_to_rgb) (void*);
static void (*qpng_set_tRNS_to_alpha) (void*);
static void (*qpng_set_gray_to_rgb) (void*);
static void (*qpng_set_filler) (void*, unsigned int, int);
-static void (*qpng_set_IHDR) (void*, void*, unsigned long, unsigned long, int, int, int, int, int);
+static void (*qpng_set_IHDR) (void*, void*, png_uint_32, png_uint_32, int, int, int, int, int);
static void (*qpng_set_packing) (void*);
static void (*qpng_set_bgr) (void*);
static int (*qpng_set_interlace_handling) (void*);
@@ -115,7 +125,7 @@ static unsigned int (*qpng_get_valid) (void*, void*, unsigned int);
static unsigned int (*qpng_get_rowbytes) (void*, void*);
static unsigned char (*qpng_get_channels) (void*, void*);
static unsigned char (*qpng_get_bit_depth) (void*, void*);
-static unsigned int (*qpng_get_IHDR) (void*, void*, unsigned long*, unsigned long*, int *, int *, int *, int *, int *);
+static png_uint_32 (*qpng_get_IHDR) (void*, void*, png_uint_32 *, png_uint_32 *, int *, int *, int *, int *, int *);
static unsigned int (*qpng_access_version_number) (void); // FIXME is this return type right? It is a png_uint_32 in libpng
static void (*qpng_write_info) (void*, void*);
static void (*qpng_write_row) (void*, unsigned char*);
@@ -300,8 +310,8 @@ static struct
int BitDepth;
int BytesPerPixel;
int ColorType;
- unsigned long Height; // retarded libpng 1.2 pngconf.h uses long (64bit/32bit depending on arch)
- unsigned long Width; // retarded libpng 1.2 pngconf.h uses long (64bit/32bit depending on arch)
+ png_uint_32 Height;
+ png_uint_32 Width;
int Interlace;
int Compression;
int Filter;
@@ -419,17 +429,23 @@ unsigned char *PNG_LoadImage_BGRA (const unsigned char *raw, int filesize, int *
qpng_read_info(png, pnginfo);
qpng_get_IHDR(png, pnginfo, &my_png.Width, &my_png.Height,&my_png.BitDepth, &my_png.ColorType, &my_png.Interlace, &my_png.Compression, &my_png.Filter);
+#ifndef LINK_TO_PNG
// this check guards against pngconf.h with unsigned int *width/height parameters on big endian systems by detecting the strange values and shifting them down 32bits
// (if it's little endian the unwritten bytes are the most significant
// ones and we don't worry about that)
//
// this is only necessary because of retarded 64bit png_uint_32 types in libpng 1.2, which can (conceivably) vary by platform
+ //
+ // If LINK_TO_PNG is defined, we should never need this,
+ // because we get the correct definition of png_uint_32 from the
+ // system libpng header.
#if LONG_MAX > 4000000000
if (my_png.Width > LONG_MAX || my_png.Height > LONG_MAX)
{
my_png.Width >>= 32;
my_png.Height >>= 32;
}
+#endif
#endif
if (my_png.ColorType == PNG_COLOR_TYPE_PALETTE)
--
2.39.5