[pull] libpng16 from pnggroup:libpng16

.appveyor.yml

@@ -2,7 +2,8 @@ version: 1.6.x-{build}
 
 branches:
   except:
-    - /libpng[0-1][0-7]/
+    - /libpng[0-1][0-8]/
+    - /v[0-1][.][0-8][.][0-9]+/
 
 image:
   - Visual Studio 2022
@@ -47,6 +48,7 @@ install:
   - 'if "%TOOLCHAIN%"=="vstudio" C:\tools\vcpkg\vcpkg.exe integrate install'
   - 'if "%TOOLCHAIN%"=="llvm" C:\tools\vcpkg\vcpkg.exe install zlib:%ARCH%-windows'
   - 'if "%TOOLCHAIN%"=="llvm" C:\tools\vcpkg\vcpkg.exe integrate install'
+  - 'if "%TOOLCHAIN%"=="msys2" if "%AUTOMATION%"=="cmake" C:\msys64\usr\bin\pacman.exe -S --noconfirm mingw-w64-%ARCH%-cmake mingw-w64-%ARCH%-ninja'
 
 before_build:
   - 'if "%TOOLCHAIN%"=="vstudio" set CI_CMAKE_GENERATOR=Visual Studio 17 2022'
@@ -57,11 +59,11 @@ before_build:
   - 'if "%TOOLCHAIN%"=="vstudio" if "%ARCH%"=="arm64" set CI_CMAKE_VARS=-DPNG_TESTS=0'
   - 'if "%TOOLCHAIN%"=="llvm" set CI_CMAKE_GENERATOR=Ninja'
   - 'if "%TOOLCHAIN%"=="llvm" set CI_CMAKE_TOOLCHAIN_FILE=C:\tools\vcpkg\scripts\buildsystems\vcpkg.cmake'
-  - 'if "%TOOLCHAIN%"=="llvm" set CI_CC=clang.exe'
-  - 'if "%TOOLCHAIN%"=="msys2" if "%AUTOMATION%"=="cmake" set CI_CMAKE_GENERATOR=Unix Makefiles'
-  - 'if "%TOOLCHAIN%"=="msys2" if "%ARCH%"=="i686" set PATH=C:\msys64\mingw32\bin;%PATH%'
-  - 'if "%TOOLCHAIN%"=="msys2" if "%ARCH%"=="x86_64" set PATH=C:\msys64\mingw64\bin;%PATH%'
-  - 'if "%TOOLCHAIN%"=="msys2" set CI_CC=%ARCH%-w64-mingw32-gcc.exe'
+  - 'if "%TOOLCHAIN%"=="llvm" set CI_CC=clang'
+  - 'if "%TOOLCHAIN%"=="msys2" set CI_CMAKE_GENERATOR=Ninja'
+  - 'if "%TOOLCHAIN%"=="msys2" set CI_CC=gcc'
+  - 'if "%TOOLCHAIN%"=="msys2" if "%ARCH%"=="i686" set MSYSTEM=MINGW32'
+  - 'if "%TOOLCHAIN%"=="msys2" if "%ARCH%"=="x86_64" set MSYSTEM=MINGW64'
   - 'set CI_CMAKE_BUILD_FLAGS=-j2'
   - 'set CI_CTEST_FLAGS=-j2'
   - 'set CI_MAKE_FLAGS=-j2'
@@ -75,4 +77,5 @@ build_script:
   - 'if "%TOOLCHAIN%"=="msys2" if "%AUTOMATION%"=="makefiles" C:\msys64\usr\bin\bash.exe -l "%APPVEYOR_BUILD_FOLDER%\ci\ci_verify_makefiles.sh"'
 
 cache:
-  - C:\tools\vcpkg\installed
+  - 'C:\tools\vcpkg\installed'
+  - 'C:\msys64\var\cache\pacman'

.cmake-format.yaml

@@ -0,0 +1,94 @@
+# https://pypi.org/project/cmakelang
+# https://github.com/cheshirekow/cmake_format
+
+# ----------------------
+# Options for formatting
+# ----------------------
+
+# How wide to allow formatted cmake files
+# TODO: Reflow the CMake files to allow setting the maximum line width to 100.
+line_width: 255
+
+# How many spaces to tab for indent
+tab_size: 2
+
+# If true, lines are indented using tab characters (utf-8 0x09) instead of
+# <tab_size> space characters (utf-8 0x20). In cases where the layout would
+# require a fractional tab character, the behavior of the fractional
+# indentation is governed by <fractional_tab_policy>
+use_tabchars: false
+
+# If <use_tabchars> is True, then the value of this variable indicates how
+# fractional indentions are handled during whitespace replacement. If set to
+# 'use-space', fractional indentation is left as spaces (utf-8 0x20). If set
+# to `round-up` fractional indentation is replaced with a single tab character
+# (utf-8 0x09) effectively shifting the column to the next tabstop
+fractional_tab_policy: "use-space"
+
+# Enable comment markup parsing and reflow
+enable_markup: false
+
+# -------------------
+# Options for linting
+# -------------------
+
+# Lint codes to disable
+disabled_codes: [
+  # TODO:
+  # Reconcile the CMake variable names with the patterns below, then
+  # re-enable the "invalid variable name XXX" messages.
+  "C0103",
+
+  # A custom command with one output doesn't really need a comment because
+  # the default "generating XXX" is a good message already.
+  "C0113",
+]
+
+# Regular expression pattern describing valid function names
+function_pattern: "[0-9a-z_]+"
+
+# Regular expression pattern describing valid macro names
+macro_pattern: "[0-9A-Z_]+"
+
+# Regular expression pattern describing valid names for variables with global
+# (cache) scope
+global_var_pattern: "[A-Z][0-9A-Z_]+"
+
+# Regular expression pattern describing valid names for variables with global
+# scope (but internal semantic)
+internal_var_pattern: "_[A-Z][0-9A-Z_]+"
+
+# Regular expression pattern describing valid names for variables with local
+# scope
+local_var_pattern: "[a-z][a-z0-9_]+"
+
+# Regular expression pattern describing valid names for privatedirectory
+# variables
+private_var_pattern: "_[0-9a-z_]+"
+
+# Regular expression pattern describing valid names for public directory
+# variables
+public_var_pattern: "[A-Z][0-9A-Z_]+"
+
+# Regular expression pattern describing valid names for function/macro
+# arguments and loop variables.
+argument_var_pattern: "[a-z][a-z0-9_]+"
+
+# Regular expression pattern describing valid names for keywords used in
+# functions or macros
+keyword_pattern: "[A-Z][0-9A-Z_]+"
+
+# In the heuristic for C0201, how many conditionals to match within a loop in
+# before considering the loop a parser
+max_conditionals_custom_parser: 2
+
+# Require at least this many newlines between statements
+min_statement_spacing: 1
+
+# Require no more than this many newlines between statements
+max_statement_spacing: 2
+max_returns: 6
+max_branches: 12
+max_arguments: 5
+max_localvars: 15
+max_statements: 50

.editorconfig

@@ -7,32 +7,49 @@ charset = utf-8
 insert_final_newline = true
 trim_trailing_whitespace = true
 
-# Traditionally, the end-of-line character has been platform-specific.
-end_of_line = unset
+[*.txt]
+indent_size = unset
+indent_style = space
 
 [*.[chS]]
+indent_size = 3
+indent_style = space
+max_doc_length = 80
+max_line_length = 80
+
+[*.dfa]
+indent_size = 3
 indent_style = space
-max_line_length = 81
+max_doc_length = 80
+max_line_length = 80
 
-[*.{awk,cmake,dfa,in,sh}]
+[*.awk]
+indent_size = 3
 indent_style = space
+max_doc_length = 80
 max_line_length = 100
 
-[*.txt]
+[*.cmake]
+indent_size = 2
 indent_style = space
-max_line_length = unset
+max_doc_length = 80
+max_line_length = 100
 
-[{Makefile.in,ltmain.sh}]
-indent_style = unset
-insert_final_newline = unset
-max_line_length = unset
-trim_trailing_whitespace = unset
+[*.sh]
+indent_size = 4
+indent_style = space
+max_doc_length = 100
+max_line_length = 100
 
-[*~]
+[{Makefile.in,aclocal.m4,ltmain.sh}]
+indent_size = unset
 indent_style = unset
 insert_final_newline = unset
+max_doc_length = unset
 max_line_length = unset
 trim_trailing_whitespace = unset
 
 [COMMIT_EDITMSG]
+indent_style = space
+max_doc_length = unset
 max_line_length = 72

.editorconfig-checker.json

@@ -0,0 +1,9 @@
+{
+  "Disable": {
+    "IndentSize": true
+  },
+  "Exclude": [
+    ".git/",
+    "out/"
+  ]
+}

.github/workflows/lint.yml

@@ -0,0 +1,29 @@
+name: Linting libpng
+
+on:
+  push:
+    branches:
+      - libpng16
+      - libpng18
+  pull_request:
+    branches:
+      - libpng16
+      - libpng18
+
+jobs:
+  lint:
+    runs-on: ubuntu-latest
+    timeout-minutes: 5
+    steps:
+      - name: Set up the cache
+        uses: actions/cache@v4
+        with:
+          path: ~/.cache/pip
+          key: ${{ runner.os }}-pip-${{ hashFiles('**/pip.txt') }}
+          restore-keys: ${{ runner.os }}-pip-
+      - name: Install yamllint
+        run: pip install yamllint
+      - name: Check out the code
+        uses: actions/checkout@v4
+      - name: Run the linting script
+        run: bash ./ci/ci_lint.sh

.gitignore

@@ -31,39 +31,119 @@
 # Compiled executables
 *.app/
 *.exe
+a.out
 
 # Debug files
 *.dSYM/
 *.idb
 *.pdb
 *.su
 
-# Libpng configuration and build artifacts
+# Tag files
+TAGS
+.TAGS
+!TAGS/
+tags
+.tags
+!tags/
+gtags.files
+GTAGS
+GRTAGS
+GPATH
+GSYMS
+cscope.files
+cscope.out
+cscope.*.out
+
+# Text editing and text processing artifacts
+\#*\#
+.\#*
+[._]*.sw[a-p]
+[._]sw[a-p]
+*.bak
+*.orig
+*.rej
+*.tmp
+*~
+
+# IDE files and directories
+## Eclipse
+.cproject/
+.project/
+.settings/
+## Embarcadero RAD Studio
+*.cbproj.*
+__recovery/
+## JetBrains
+.idea/
+## NetBeans
+nbbuild/
+nbdist/
+nbproject/
+## Visual Studio
+.vs/
+### Visual Studio user files
+*.rsuser
+*.sln.docstates
+*.suo
+*.user
+*.userprefs
+### Visual Studio cache files (for older versions)
+*.aps
+*.ncb
+*.opensdf
+*.sdf
+*.VC.db
+*.VC.opendb
+ipch/
+## Visual Studio Code
+.vscode/*
+!.vscode/extensions.json
+!.vscode/launch.json
+!.vscode/settings.json
+!.vscode/tasks.json
+## (Various)
+*.*cache
+*.cache*
+[._]*_history
+.history/
+[Bb]ackup*/
+
+# Build, test and CI output directories
+*[Dd]ebug/
+[Dd]ebug*/
+*[Rr]elease/
+[Rr]elease*/
+[._]build*/
+/[Bb]uild*/
+/[Oo]ut/
+
+# Libpng configuration and auxiliary build artifacts
 *.out
-.deps/
+*out.png
+[._]deps/
 .dirstamp
 /Makefile
 /autom4te.cache/
-/config.guess~
-/config.h.in~
+/config*~
+/config.h
 /config.log
 /config.status
-/config.sub~
-/configure~
-/install-sh~
-/libpng-config
-/libpng.pc
+/install*~
+/libpng*-config
+/libpng*.pc
 /libpng.vers
-/libpng16-config
-/libpng16.pc
 /libtool
 /stamp-h1
+CMake*.json
+!CMakePresets.json
+CMakeLists.txt.*
 pnglibconf.[ch]
 pnglibconf.dfn
 pnglibconf.pre
 pngprefix.h
 
-# Libpng test artifacts
+# Libpng test programs
 png-fix-itxt
 pngcp
 pngfix
@@ -73,7 +153,3 @@ pngtest
 pngunknown
 pngvalid
 timepng
-pngout.png
-
-# Libpng CI artifacts
-out/