libpng: Update to 1.6.43

(cherry picked from commit 41268d7)

Author: Chubercik

COPYRIGHT.txt

@@ -197,8 +197,8 @@ License: BSD-3-clause
 
 Files: ./thirdparty/libpng/
 Comment: libpng
-Copyright: 1995-2019, The PNG Reference Library Authors.
- 2018-2019, Cosmin Truta.
+Copyright: 1995-2024, The PNG Reference Library Authors.
+ 2018-2024, Cosmin Truta.
  2000-2002, 2004, 2006-2018 Glenn Randers-Pehrson.
  1996-1997, Andreas Dilger.
  1995-1996, Guy Eric Schalnat, Group 42, Inc.

thirdparty/README.md

@@ -178,14 +178,14 @@ Files extracted from upstream source:
 ## libpng
 
 - Upstream: http://libpng.org/pub/png/libpng.html
-- Version: 1.6.40 (f135775ad4e5d4408d2e12ffcc71bb36e6b48551, 2023)
+- Version: 1.6.43 (ed217e3e601d8e462f7fd1e04bed43ac42212429, 2024)
 - License: libpng/zlib
 
 Files extracted from upstream source:
 
-- all .c and .h files of the main directory, except from
-  `example.c` and `pngtest.c`
-- the arm/ folder
+- All `.c` and `.h` files of the main directory, apart from `example.c` and
+  `pngtest.c`
+- The `arm/` folder
 - `scripts/pnglibconf.h.prebuilt` as `pnglibconf.h`
 - `LICENSE`
 

thirdparty/libpng/LICENSE

@@ -4,8 +4,8 @@ COPYRIGHT NOTICE, DISCLAIMER, and LICENSE
 PNG Reference Library License version 2
 ---------------------------------------
 
- * Copyright (c) 1995-2023 The PNG Reference Library Authors.
- * Copyright (c) 2018-2023 Cosmin Truta.
+ * Copyright (c) 1995-2024 The PNG Reference Library Authors.
+ * Copyright (c) 2018-2024 Cosmin Truta.
  * Copyright (c) 2000-2002, 2004, 2006-2018 Glenn Randers-Pehrson.
  * Copyright (c) 1996-1997 Andreas Dilger.
  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.

thirdparty/libpng/png.c

@@ -1,7 +1,7 @@
 
 /* png.c - location for general purpose libpng functions
  *
- * Copyright (c) 2018-2023 Cosmin Truta
+ * Copyright (c) 2018-2024 Cosmin Truta
  * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
  * Copyright (c) 1996-1997 Andreas Dilger
  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
@@ -14,27 +14,7 @@
 #include "pngpriv.h"
 
 /* Generate a compiler error if there is an old png.h in the search path. */
-typedef png_libpng_version_1_6_40 Your_png_h_is_not_version_1_6_40;
-
-#ifdef __GNUC__
-/* The version tests may need to be added to, but the problem warning has
- * consistently been fixed in GCC versions which obtain wide-spread release.
- * The problem is that many versions of GCC rearrange comparison expressions in
- * the optimizer in such a way that the results of the comparison will change
- * if signed integer overflow occurs.  Such comparisons are not permitted in
- * ANSI C90, however GCC isn't clever enough to work out that that do not occur
- * below in png_ascii_from_fp and png_muldiv, so it produces a warning with
- * -Wextra.  Unfortunately this is highly dependent on the optimizer and the
- * machine architecture so the warning comes and goes unpredictably and is
- * impossible to "fix", even were that a good idea.
- */
-#if __GNUC__ == 7 && __GNUC_MINOR__ == 1
-#define GCC_STRICT_OVERFLOW 1
-#endif /* GNU 7.1.x */
-#endif /* GNU */
-#ifndef GCC_STRICT_OVERFLOW
-#define GCC_STRICT_OVERFLOW 0
-#endif
+typedef png_libpng_version_1_6_43 Your_png_h_is_not_version_1_6_43;
 
 /* Tells libpng that we have already handled the first "num_bytes" bytes
  * of the PNG file signature.  If the PNG data is embedded into another
@@ -73,21 +53,21 @@ png_set_sig_bytes(png_structrp png_ptr, int num_bytes)
 int PNGAPI
 png_sig_cmp(png_const_bytep sig, size_t start, size_t num_to_check)
 {
-   png_byte png_signature[8] = {137, 80, 78, 71, 13, 10, 26, 10};
+   static const png_byte png_signature[8] = {137, 80, 78, 71, 13, 10, 26, 10};
 
    if (num_to_check > 8)
       num_to_check = 8;
 
    else if (num_to_check < 1)
-      return (-1);
+      return -1;
 
    if (start > 7)
-      return (-1);
+      return -1;
 
    if (start + num_to_check > 8)
       num_to_check = 8 - start;
 
-   return ((int)(memcmp(&sig[start], &png_signature[start], num_to_check)));
+   return memcmp(&sig[start], &png_signature[start], num_to_check);
 }
 
 #endif /* READ */
@@ -447,7 +427,6 @@ png_info_init_3,(png_infopp ptr_ptr, size_t png_info_struct_size),
    memset(info_ptr, 0, (sizeof *info_ptr));
 }
 
-/* The following API is not called internally */
 void PNGAPI
 png_data_freer(png_const_structrp png_ptr, png_inforp info_ptr,
     int freer, png_uint_32 mask)
@@ -686,9 +665,9 @@ png_voidp PNGAPI
 png_get_io_ptr(png_const_structrp png_ptr)
 {
    if (png_ptr == NULL)
-      return (NULL);
+      return NULL;
 
-   return (png_ptr->io_ptr);
+   return png_ptr->io_ptr;
 }
 
 #if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
@@ -752,7 +731,7 @@ png_convert_to_rfc1123_buffer(char out[29], png_const_timep ptime)
 
    {
       size_t pos = 0;
-      char number_buf[5]; /* enough for a four-digit year */
+      char number_buf[5] = {0, 0, 0, 0, 0}; /* enough for a four-digit year */
 
 #     define APPEND_STRING(string) pos = png_safecat(out, 29, pos, (string))
 #     define APPEND_NUMBER(format, value)\
@@ -815,8 +794,8 @@ png_get_copyright(png_const_structrp png_ptr)
    return PNG_STRING_COPYRIGHT
 #else
    return PNG_STRING_NEWLINE \
-      "libpng version 1.6.40" PNG_STRING_NEWLINE \
-      "Copyright (c) 2018-2023 Cosmin Truta" PNG_STRING_NEWLINE \
+      "libpng version 1.6.43" PNG_STRING_NEWLINE \
+      "Copyright (c) 2018-2024 Cosmin Truta" PNG_STRING_NEWLINE \
       "Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson" \
       PNG_STRING_NEWLINE \
       "Copyright (c) 1996-1997 Andreas Dilger" PNG_STRING_NEWLINE \
@@ -977,7 +956,7 @@ png_reset_zstream(png_structrp png_ptr)
       return Z_STREAM_ERROR;
 
    /* WARNING: this resets the window bits to the maximum! */
-   return (inflateReset(&png_ptr->zstream));
+   return inflateReset(&png_ptr->zstream);
 }
 #endif /* READ */
 
@@ -986,7 +965,7 @@ png_uint_32 PNGAPI
 png_access_version_number(void)
 {
    /* Version of *.c files used when building libpng */
-   return((png_uint_32)PNG_LIBPNG_VER);
+   return (png_uint_32)PNG_LIBPNG_VER;
 }
 
 #if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
@@ -1842,14 +1821,14 @@ png_icc_profile_error(png_const_structrp png_ptr, png_colorspacerp colorspace,
    }
 #  ifdef PNG_WARNINGS_SUPPORTED
    else
-      {
-         char number[PNG_NUMBER_BUFFER_SIZE]; /* +24 = 114 */
+   {
+      char number[PNG_NUMBER_BUFFER_SIZE]; /* +24 = 114 */
 
-         pos = png_safecat(message, (sizeof message), pos,
-             png_format_number(number, number+(sizeof number),
-             PNG_NUMBER_FORMAT_x, value));
-         pos = png_safecat(message, (sizeof message), pos, "h: "); /* +2 = 116 */
-      }
+      pos = png_safecat(message, (sizeof message), pos,
+          png_format_number(number, number+(sizeof number),
+          PNG_NUMBER_FORMAT_x, value));
+      pos = png_safecat(message, (sizeof message), pos, "h: "); /* +2 = 116 */
+   }
 #  endif
    /* The 'reason' is an arbitrary message, allow +79 maximum 195 */
    pos = png_safecat(message, (sizeof message), pos, reason);
@@ -2532,17 +2511,6 @@ png_colorspace_set_rgb_coefficients(png_structrp png_ptr)
 
 #endif /* COLORSPACE */
 
-#ifdef __GNUC__
-/* This exists solely to work round a warning from GNU C. */
-static int /* PRIVATE */
-png_gt(size_t a, size_t b)
-{
-   return a > b;
-}
-#else
-#   define png_gt(a,b) ((a) > (b))
-#endif
-
 void /* PRIVATE */
 png_check_IHDR(png_const_structrp png_ptr,
     png_uint_32 width, png_uint_32 height, int bit_depth,
@@ -2564,8 +2532,16 @@ png_check_IHDR(png_const_structrp png_ptr,
       error = 1;
    }
 
-   if (png_gt(((width + 7) & (~7U)),
-       ((PNG_SIZE_MAX
+   /* The bit mask on the first line below must be at least as big as a
+    * png_uint_32.  "~7U" is not adequate on 16-bit systems because it will
+    * be an unsigned 16-bit value.  Casting to (png_alloc_size_t) makes the
+    * type of the result at least as bit (in bits) as the RHS of the > operator
+    * which also avoids a common warning on 64-bit systems that the comparison
+    * of (png_uint_32) against the constant value on the RHS will always be
+    * false.
+    */
+   if (((width + 7) & ~(png_alloc_size_t)7) >
+       (((PNG_SIZE_MAX
            - 48        /* big_row_buf hack */
            - 1)        /* filter byte */
            / 8)        /* 8-byte RGBA pixels */
@@ -2891,14 +2867,6 @@ png_pow10(int power)
 /* Function to format a floating point value in ASCII with a given
  * precision.
  */
-#if GCC_STRICT_OVERFLOW
-#pragma GCC diagnostic push
-/* The problem arises below with exp_b10, which can never overflow because it
- * comes, originally, from frexp and is therefore limited to a range which is
- * typically +/-710 (log2(DBL_MAX)/log2(DBL_MIN)).
- */
-#pragma GCC diagnostic warning "-Wstrict-overflow=2"
-#endif /* GCC_STRICT_OVERFLOW */
 void /* PRIVATE */
 png_ascii_from_fp(png_const_structrp png_ptr, png_charp ascii, size_t size,
     double fp, unsigned int precision)
@@ -3220,10 +3188,6 @@ png_ascii_from_fp(png_const_structrp png_ptr, png_charp ascii, size_t size,
    /* Here on buffer too small. */
    png_error(png_ptr, "ASCII conversion buffer too small");
 }
-#if GCC_STRICT_OVERFLOW
-#pragma GCC diagnostic pop
-#endif /* GCC_STRICT_OVERFLOW */
-
 #  endif /* FLOATING_POINT */
 
 #  ifdef PNG_FIXED_POINT_SUPPORTED
@@ -3251,7 +3215,7 @@ png_ascii_from_fixed(png_const_structrp png_ptr, png_charp ascii,
       if (num <= 0x80000000) /* else overflowed */
       {
          unsigned int ndigits = 0, first = 16 /* flag value */;
-         char digits[10];
+         char digits[10] = {0};
 
          while (num)
          {
@@ -3336,15 +3300,6 @@ png_fixed(png_const_structrp png_ptr, double fp, png_const_charp text)
  * the nearest .00001).  Overflow and divide by zero are signalled in
  * the result, a boolean - true on success, false on overflow.
  */
-#if GCC_STRICT_OVERFLOW /* from above */
-/* It is not obvious which comparison below gets optimized in such a way that
- * signed overflow would change the result; looking through the code does not
- * reveal any tests which have the form GCC complains about, so presumably the
- * optimizer is moving an add or subtract into the 'if' somewhere.
- */
-#pragma GCC diagnostic push
-#pragma GCC diagnostic warning "-Wstrict-overflow=2"
-#endif /* GCC_STRICT_OVERFLOW */
 int
 png_muldiv(png_fixed_point_p res, png_fixed_point a, png_int_32 times,
     png_int_32 divisor)
@@ -3459,9 +3414,6 @@ png_muldiv(png_fixed_point_p res, png_fixed_point a, png_int_32 times,
 
    return 0;
 }
-#if GCC_STRICT_OVERFLOW
-#pragma GCC diagnostic pop
-#endif /* GCC_STRICT_OVERFLOW */
 #endif /* READ_GAMMA || INCH_CONVERSIONS */
 
 #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_INCH_CONVERSIONS_SUPPORTED)