Merge tag 'v1.6.46' into libpng18

Sync with libpng version 1.6.46

.editorconfig

@@ -41,7 +41,7 @@ indent_style = space
 max_doc_length = 100
 max_line_length = 100
 
-[{Makefile.in,ltmain.sh}]
+[{Makefile.in,aclocal.m4,ltmain.sh}]
 indent_size = unset
 indent_style = unset
 insert_final_newline = unset

CHANGES

@@ -6229,6 +6229,16 @@ Version 1.6.45 [January 7, 2025]
   Raised the minimum required CMake version from 3.6 to 3.14.
   Forked off a development branch for libpng version 1.8.
 
+Version 1.6.46 [January 23, 2025]
+  Added support for the mDCV and cLLI chunks.
+    (Contributed by John Bowler)
+  Fixed a build issue affecting C89 compilers.
+    This was a regression introduced in libpng-1.6.45.
+    (Contributed by John Bowler)
+  Added makefile.c89, specifically for testing C89 compilers.
+  Cleaned up contrib/pngminus: corrected an old typo, removed an old
+    workaround, and updated the CMake file.
+
 Version 1.8.0 [TODO]
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net.

Makefile.am

@@ -1,6 +1,6 @@
 # Makefile.am, the source file for Makefile.in (and hence Makefile), is
 #
-# Copyright (c) 2018-2024 Cosmin Truta
+# Copyright (c) 2018-2025 Cosmin Truta
 # Copyright (c) 2004-2016 Glenn Randers-Pehrson
 #
 # This code is released under the libpng license.
@@ -159,7 +159,7 @@ MAINTAINERCLEANFILES = Makefile.in aclocal.m4 config.guess config.h.in \
 config.sub configure depcomp install-sh ltmain.sh missing
 
 # PNG_COPTS give extra options for the C compiler to be used on all compilation
-# steps (unless targe_CFLAGS is specified; that will take precedence over
+# steps (unless target_CFLAGS is specified; that will take precedence over
 # AM_CFLAGS)
 PNG_COPTS = @PNG_COPTS@
 AM_CFLAGS = ${PNG_COPTS}

ci/README.md

@@ -0,0 +1,25 @@
+Scripts for the Continuous Integration of the PNG Reference Library
+===================================================================
+
+Copyright Notice
+----------------
+
+Copyright (c) 2019-2024 Cosmin Truta.
+
+Use, modification and distribution are subject to the MIT License.
+Please see the accompanying file `LICENSE_MIT.txt` or visit
+https://opensource.org/license/mit
+
+File List
+---------
+
+    LICENSE_MIT.txt         ==>  The License file
+    README.md               ==>  This file
+    ci_lint.sh              ==>  Lint the source code
+    ci_shellify.sh          ==>  Convert select definitions to shell syntax
+    ci_verify_cmake.sh      ==>  Verify the build driven by CMakeLists.txt
+    ci_verify_configure.sh  ==>  Verify the build driven by configure
+    ci_verify_makefiles.sh  ==>  Verify the build driven by scripts/makefile.*
+    ci_verify_version.sh    ==>  Verify the consistency of version definitions
+    lib/ci.lib.sh           ==>  Shell utilities for the main ci_*.sh scripts
+    targets/*/ci_env.*.sh   ==>  Shell environments for cross-platform testing

contrib/libtests/pngunknown.c

@@ -112,6 +112,8 @@ typedef png_byte *png_const_bytep;
 #define png_PLTE PNG_U32( 80,  76,  84,  69)
 #define png_bKGD PNG_U32( 98,  75,  71,  68)
 #define png_cHRM PNG_U32( 99,  72,  82,  77)
+#define png_cICP PNG_U32( 99,  73,  67,  80) /* PNGv3 */
+#define png_cLLI PNG_U32( 99,  76,  76,  73) /* PNGv3 */
 #define png_eXIf PNG_U32(101,  88,  73, 102) /* registered July 2017 */
 #define png_fRAc PNG_U32(102,  82,  65,  99) /* registered, not defined */
 #define png_gAMA PNG_U32(103,  65,  77,  65)
@@ -121,6 +123,7 @@ typedef png_byte *png_const_bytep;
 #define png_hIST PNG_U32(104,  73,  83,  84)
 #define png_iCCP PNG_U32(105,  67,  67,  80)
 #define png_iTXt PNG_U32(105,  84,  88, 116)
+#define png_mDCV PNG_U32(109,  68,  67,  86) /* PNGv3 */
 #define png_oFFs PNG_U32(111,  70,  70, 115)
 #define png_pCAL PNG_U32(112,  67,  65,  76)
 #define png_pHYs PNG_U32(112,  72,  89, 115)
@@ -205,6 +208,20 @@ static struct
          0,
 #     else
          1,
+#     endif
+      1,  START, 0 },
+   { "cICP", PNG_INFO_cICP, png_cICP,
+#     ifdef PNG_READ_cICP_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1,  START, 0 },
+   { "cLLI", PNG_INFO_cLLI, png_cLLI,
+#     ifdef PNG_READ_cLLI_SUPPORTED
+         0,
+#     else
+         1,
 #     endif
       1,  START, 0 },
    { "eXIf", PNG_INFO_eXIf, png_eXIf,
@@ -242,6 +259,13 @@ static struct
          1,
 #     endif
       1, ABSENT, 0 },
+   { "mDCV", PNG_INFO_mDCV, png_mDCV,
+#     ifdef PNG_READ_mDCV_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1,  START, 0 },
    { "oFFs", PNG_INFO_oFFs, png_oFFs,
 #     ifdef PNG_READ_oFFs_SUPPORTED
          0,

contrib/pngminus/.editorconfig

@@ -0,0 +1,29 @@
+# https://editorconfig.org
+
+root = true
+
+[*]
+charset = utf-8
+end_of_line = unset
+indent_size = unset
+indent_style = space
+insert_final_newline = true
+max_doc_length = 79
+max_line_length = 79
+trim_trailing_whitespace = true
+
+[*.[ch]]
+indent_size = 2
+indent_style = space
+
+[CMakeLists.txt]
+indent_size = 4
+indent_style = space
+max_doc_length = 79
+max_line_length = 99
+
+[{Makefile,makevms.com}]
+indent_size = unset
+indent_style = unset
+max_doc_length = 79
+max_line_length = 99

contrib/pngminus/CHANGES.txt

@@ -11,3 +11,4 @@ version 1.0 - 1999.10.15 - First version.
         1.6 - 2018.08.05 - Improve portability and fix style (Cosmin Truta)
         1.7 - 2019.01.22 - Change license to MIT (Willem van Schaik)
         1.8 - 2024.01.09 - Fix, improve, modernize (Cosmin Truta)
+        1.9 - 2025.01.10 - Delete conditionally-compiled code (Cosmin Truta)

contrib/pngminus/CMakeLists.txt

@@ -1,9 +1,9 @@
-# Copyright (c) 2018-2024 Cosmin Truta
+# Copyright (c) 2018-2025 Cosmin Truta
 #
 # This software is released under the MIT license. For conditions of
 # distribution and use, see the LICENSE file part of this package.
 
-cmake_minimum_required(VERSION 3.5)
+cmake_minimum_required(VERSION 3.14)
 
 project(PNGMINUS C)
 

contrib/pngminus/png2pnm.c

@@ -66,7 +66,7 @@ int main (int argc, char *argv[])
           if ((fp_al = fopen (argv[argi], "wb")) == NULL)
           {
             fname_al = argv[argi];
-            fprintf (stderr, "PNM2PNG\n");
+            fprintf (stderr, "PNG2PNM\n");
             fprintf (stderr, "Error:  cannot create alpha-channel file %s\n",
                      argv[argi]);
             exit (1);
@@ -235,22 +235,6 @@ BOOL do_png2pnm (png_struct *png_ptr, png_info *info_ptr,
   /* set up (if applicable) the expansion of grayscale images to bit-depth 8 */
   png_set_expand_gray_1_2_4_to_8 (png_ptr);
 
-#ifdef NJET
-  /* downgrade 16-bit images to 8-bit */
-  if (bit_depth == 16)
-    png_set_strip_16 (png_ptr);
-  /* transform grayscale images into full-color */
-  if (color_type == PNG_COLOR_TYPE_GRAY ||
-      color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
-    png_set_gray_to_rgb (png_ptr);
-  /* if the PNG image has a gAMA chunk then gamma-correct the output image */
-  {
-    double file_gamma;
-    if (png_get_gAMA (png_ptr, info_ptr, &file_gamma))
-      png_set_gamma (png_ptr, (double) 2.2, file_gamma);
-  }
-#endif
-
   /* read the image file, with all of the above image transforms applied */
   png_read_png (png_ptr, info_ptr, 0, NULL);
 

manuals/libpng-manual.txt

@@ -9,7 +9,7 @@ libpng-manual.txt - A description on how to use and modify libpng
 
  Based on:
 
- libpng version 1.6.36, December 2018, through 1.6.45 - January 2025
+ libpng version 1.6.36, December 2018, through 1.6.46 - January 2025
  Updated and distributed by Cosmin Truta
  Copyright (c) 2018-2025 Cosmin Truta
 

manuals/libpng.3

@@ -1,6 +1,6 @@
-.TH LIBPNG 3 "January 7, 2025"
+.TH LIBPNG 3 "January 23, 2025"
 .SH NAME
-libpng \- Portable Network Graphics (PNG) Reference Library 1.6.45
+libpng \- Portable Network Graphics (PNG) Reference Library 1.6.46
 
 .SH SYNOPSIS
 \fB#include <png.h>\fP
@@ -518,7 +518,7 @@ libpng-manual.txt - A description on how to use and modify libpng
 
  Based on:
 
- libpng version 1.6.36, December 2018, through 1.6.45 - January 2025
+ libpng version 1.6.36, December 2018, through 1.6.46 - January 2025
  Updated and distributed by Cosmin Truta
  Copyright (c) 2018-2025 Cosmin Truta
 

manuals/png.5

@@ -1,4 +1,4 @@
-.TH PNG 5 "January 7, 2025"
+.TH PNG 5 "January 23, 2025"
 .SH NAME
 png \- Portable Network Graphics (PNG) format
 

png.c

@@ -1521,56 +1521,59 @@ png_XYZ_from_xy(png_XYZ *XYZ, const png_xy *xy)
     *  Adobe Wide Gamut RGB
     *    0.258728243040113 0.724682314948566 0.016589442011321
     */
-   int error = 0;
-
-   /* By the argument above overflow should be impossible here, however the
-    * code now simply returns a failure code.  The xy subtracts in the arguments
-    * to png_muldiv are *not* checked for overflow because the checks at the
-    * start guarantee they are in the range 0..110000 and png_fixed_point is a
-    * 32-bit signed number.
-    */
-   if (png_muldiv(&left, xy->greenx-xy->bluex, xy->redy - xy->bluey, 8) == 0)
-      return 1;
-   if (png_muldiv(&right, xy->greeny-xy->bluey, xy->redx - xy->bluex, 8) == 0)
-      return 1;
-   denominator = png_fp_sub(left, right, &error);
-   if (error) return 1;
+   {
+      int error = 0;
 
-   /* Now find the red numerator. */
-   if (png_muldiv(&left, xy->greenx-xy->bluex, xy->whitey-xy->bluey, 8) == 0)
-      return 1;
-   if (png_muldiv(&right, xy->greeny-xy->bluey, xy->whitex-xy->bluex, 8) == 0)
-      return 1;
+      /* By the argument above overflow should be impossible here, however the
+       * code now simply returns a failure code.  The xy subtracts in the
+       * arguments to png_muldiv are *not* checked for overflow because the
+       * checks at the start guarantee they are in the range 0..110000 and
+       * png_fixed_point is a 32-bit signed number.
+       */
+      if (png_muldiv(&left, xy->greenx-xy->bluex, xy->redy - xy->bluey, 8) == 0)
+         return 1;
+      if (png_muldiv(&right, xy->greeny-xy->bluey, xy->redx - xy->bluex, 8) ==
+            0)
+         return 1;
+      denominator = png_fp_sub(left, right, &error);
+      if (error) return 1;
 
-   /* Overflow is possible here and it indicates an extreme set of PNG cHRM
-    * chunk values.  This calculation actually returns the reciprocal of the
-    * scale value because this allows us to delay the multiplication of white-y
-    * into the denominator, which tends to produce a small number.
-    */
-   if (png_muldiv(&red_inverse, xy->whitey, denominator,
-                  png_fp_sub(left, right, &error)) == 0 || error ||
-       red_inverse <= xy->whitey /* r+g+b scales = white scale */)
-      return 1;
+      /* Now find the red numerator. */
+      if (png_muldiv(&left, xy->greenx-xy->bluex, xy->whitey-xy->bluey, 8) == 0)
+         return 1;
+      if (png_muldiv(&right, xy->greeny-xy->bluey, xy->whitex-xy->bluex, 8) ==
+            0)
+         return 1;
 
-   /* Similarly for green_inverse: */
-   if (png_muldiv(&left, xy->redy-xy->bluey, xy->whitex-xy->bluex, 8) == 0)
-      return 1;
-   if (png_muldiv(&right, xy->redx-xy->bluex, xy->whitey-xy->bluey, 8) == 0)
-      return 1;
-   if (png_muldiv(&green_inverse, xy->whitey, denominator,
-                  png_fp_sub(left, right, &error)) == 0 || error ||
-       green_inverse <= xy->whitey)
-      return 1;
+      /* Overflow is possible here and it indicates an extreme set of PNG cHRM
+       * chunk values.  This calculation actually returns the reciprocal of the
+       * scale value because this allows us to delay the multiplication of
+       * white-y into the denominator, which tends to produce a small number.
+       */
+      if (png_muldiv(&red_inverse, xy->whitey, denominator,
+                     png_fp_sub(left, right, &error)) == 0 || error ||
+          red_inverse <= xy->whitey /* r+g+b scales = white scale */)
+         return 1;
 
-   /* And the blue scale, the checks above guarantee this can't overflow but it
-    * can still produce 0 for extreme cHRM values.
-    */
-   blue_scale = png_fp_sub(png_fp_sub(png_reciprocal(xy->whitey),
-                                      png_reciprocal(red_inverse), &error),
-                           png_reciprocal(green_inverse), &error);
-   if (error || blue_scale <= 0)
-      return 1;
+      /* Similarly for green_inverse: */
+      if (png_muldiv(&left, xy->redy-xy->bluey, xy->whitex-xy->bluex, 8) == 0)
+         return 1;
+      if (png_muldiv(&right, xy->redx-xy->bluex, xy->whitey-xy->bluey, 8) == 0)
+         return 1;
+      if (png_muldiv(&green_inverse, xy->whitey, denominator,
+                     png_fp_sub(left, right, &error)) == 0 || error ||
+          green_inverse <= xy->whitey)
+         return 1;
 
+      /* And the blue scale, the checks above guarantee this can't overflow but
+       * it can still produce 0 for extreme cHRM values.
+       */
+      blue_scale = png_fp_sub(png_fp_sub(png_reciprocal(xy->whitey),
+                                         png_reciprocal(red_inverse), &error),
+                              png_reciprocal(green_inverse), &error);
+      if (error || blue_scale <= 0)
+         return 1;
+   }
 
    /* And fill in the png_XYZ.  Again the subtracts are safe because of the
     * checks on the xy values at the start (the subtracts just calculate the
@@ -3365,6 +3368,26 @@ png_fixed(png_const_structrp png_ptr, double fp, png_const_charp text)
 }
 #endif
 
+#if defined(PNG_FLOATING_POINT_SUPPORTED) && \
+   !defined(PNG_FIXED_POINT_MACRO_SUPPORTED) && \
+   (defined(PNG_cLLI_SUPPORTED) || defined(PNG_mDCV_SUPPORTED))
+png_uint_32
+png_fixed_ITU(png_const_structrp png_ptr, double fp, png_const_charp text)
+{
+   double r = floor(10000 * fp + .5);
+
+   if (r > 2147483647. || r < 0)
+      png_fixed_error(png_ptr, text);
+
+#  ifndef PNG_ERROR_TEXT_SUPPORTED
+   PNG_UNUSED(text)
+#  endif
+
+   return (png_uint_32)r;
+}
+#endif
+
+
 #if defined(PNG_GAMMA_SUPPORTED) || defined(PNG_COLORSPACE_SUPPORTED) ||\
     defined(PNG_INCH_CONVERSIONS_SUPPORTED) || defined(PNG_READ_pHYs_SUPPORTED)
 /* muldiv functions */