This adds APIs to get/set the two remaining new PNG-v3 colour space
chunks. The mDCV API matches that of cHRM. Both chunks support
floating point APIs (all values in the two chunks are real numbers).
Both chunks have a new encoded type, a four-digit-precision fixed-point
number, which cannot be represented in the existing `png_fixed_point`
type, so a `png_uint_32` is used.
Test examples for cICP, cLLI and mDCV are now in pngtest.png, and a
necessary change to the pngunknown.c test program has been made to
accomodate the additions.
Reviewed-by: Cosmin Truta <ctruta@gmail.com>
Signed-off-by: John Bowler <jbowler@acm.org>
Signed-off-by: Cosmin Truta <ctruta@gmail.com>
In preparation for the upcoming changes in the build system, any parts
of the CMake file that are unlikely to be affected should be moved out
of the way. This should facilitate an easier resync between the branch
'libpng16' and its successor(s).
Specifically:
* Move the functions `generate_chk`, `generate_out`, `generate_source`
and `generate_copy` to scripts/cmake/PNGGenConfig.cmake.
* Move the function `png_add_test` to scripts/cmake/PNGTest.cmake.
* Leave the function `create_symlink` in place, but add a TODO note.
As we raised the minimum required CMake version to 3.14, we should
now be able to use CMake's built-in function instead.
Apply the following corrections and improvements:
* Add a validity check in `png_set_cICP`.
* Fix the ordering check in `png_handle_cICP`.
* Add a multiplicity check in `png_handle_cICP`.
* Optimize the implementation of `png_write_cICP`.
* Remove an unnecessary preprocessor guard from pngtest.c.
* Update the dependency declaration in pnglibconf.dfa.
* Fix the indentation where necessary.
This is a cherry-pick of commit c2a02691df1ecf51b7c97142752a7034350cb1f6
from branch 'libpng18'.
This chunk was added in the third edition of the PNG specification and
contains Coding Independent Code Points (related to color space
description). It is fairly simple as it only contains four fields of one
byte each: Colour Primaries, Transfer Function, Matrix Coefficients,
Video Full Range Flag.
The test file originally comes from the related WPT test case:
https://github.com/web-platform-tests/wpt/blob/master/png/support/cicp-display-p3.png
Note that I reencoded the file to make it match libpng's default
encoding parameters (it only modifies the IDAT chunk).
This is a cherry-pick of commit 65925ad4b2cbed934d5d850fe764dc46c4becbcb
from branch 'libpng18'.
Reviewed-by: John Bowler <jbowler@acm.org>
Reviewed-by: Chris Blume <ProgramMax@gmail.com>
Reviewed-by: Cosmin Truta <ctruta@gmail.com>
Signed-off-by: Cosmin Truta <ctruta@gmail.com>
Introduce CMake file linting, based on the cmakelang project by
Josh Bialkowski (@cheshirekow).
Fix various style issues in the CMake files:
* Add the missing copyright header to PNGConfig.cmake.
* Resolve a "missing docstring" warning raised by cmake-lint.
* Rewrite all docstrings in the style of CMake's own documentation.
* Fix whitespace inconsistencies.
References:
* https://pypi.org/project/cmakelang
* https://github.com/cheshirekow/cmake_format
This is a cherry-pick of commit c317fe31114d92d05d44bf98c9b559edf4656b9c
from branch 'libpng18'.
The leading blank lines are apparently an artefact of an older source
control system. They are not required and they look like accidents,
because starting a source file with a blank line is not a regular habit
of software developers nowadays.
This is a cherry-pick of commit 37cc20add8fb5b83bb5299a26cd3b41e0f776017
from branch 'libpng18'.
Signed-off-by: John Bowler <jbowler@acm.org>
Signed-off-by: Cosmin Truta <ctruta@gmail.com>
Properly declare target include directories for generated includes.
Previously the non targeted `include_directories()` was used, which
had issue when using the `png_static` target in a submodule.
Signed-off-by: Cosmin Truta <ctruta@gmail.com>
Properly declare target include directories for generated includes.
Previously the non targeted `include_directories()` was used, which
had issue when using the `png_static` target in a submodule.
Signed-off-by: Cosmin Truta <ctruta@gmail.com>
Modern compilers can disable the warnings that originate from system
headers. This change allows them to do so with the libpng headers.
Signed-off-by: Cosmin Truta <ctruta@gmail.com>
This fixes commit 4edbb4da81626a7342a22824d7a8f60a3ea71bd0.
During the move of CMake scripts to the scripts/cmake/ subdirectory,
some of the workflows have been broken.
Signed-off-by: Cosmin Truta <ctruta@gmail.com>
Split AR_RC into AR and ARFLAGS. The variables AR and ARFLAGS are
de-facto standards (like CC and CFLAGS, LD and LDFLAGS, etc.) that
may be overridden when running make. Moreover, configuring CC, LD,
AR, etc., to point to a cross-platform compiler, linker, librarian,
etc., is a de-facto standard practice as well.
Also remove the MKDIR_P variable definitions from all makefiles.
They've been leftovers from the removal of the "install*" targets.
The version macros `PNG_LIBPNG_VER_SONUM` and `PNG_LIBPNG_VER_DLLNUM`
weren't always in sync, but they should be, going forward.
Or, better yet, we should keep them in, deprecated, and introduce
`PNG_LIBPNG_VER_SHAREDLIB` for all shared library builds of all kinds
on all platforms.
It is unknown how many user applications have been using these macros.
We have been using `PNG_LIBPNG_VER_DLLNUM` for pngwin.rc, for example.
Which, by the way, was last updated in 2009.
From the libpng licensing point of view, the build projects, the build
scripts, the test scripts, the CI verification scripts, et cetera, have
not traditionally been part of libpng proper, although some of these,
including the CMake-based build, have been released under the libpng
license.
Considering how the CMake build grew as a result of many contributions
from many contributing authors over a long time, one may argue that it
almost became an individual piece of software in its own right.
Moving on, everything CMake-related shall be placed in the subdirectory
scripts/cmake/ (except, of course, the main CMakeLists.txt). Moreover,
contributing authors shall be acknowledged in scripts/cmake/AUTHORS.md.
Please see scripts/cmake/README.md for more information.
Move all Autoconf macro files (except for those that need to be in
the top-level directory) to their own subdirectory scripts/autoconf/
In this commit, we introduce a better way to organize the scripts dir,
and we make a better separation between the build scripts under the
libpng license vs. the build scripts that fall under other licenses.
Please see scripts/autoconf/README.md for more information.
This removes the default build of an undocumented feature to disable
Adler32 checksums on those systems where it was the default.
The PR is motived by github #187 however it fixes a much more general
problem (#187 is limited to an issue where libpng "crashes" on some
manufacturer systems). The fix is based on a suggestion by @sgowdev who
is the originator of the issue.
When libpng disables the checking of Adler32 checksums it does so by an
undocumented and therefore possibly unsupported call to a zlib function
which does not exist in some versions of zlib.
Fortunately libpng only does this if the caller of libpng explicitly
asks for it to happen. Unfortunately the call to the undocumented
function is still in the compiled and built libpng and this means that
on some systems (as identified in #187) libpng can fail to load or maybe
even crash.
The libpng authors are currently unaware of any program or system that
uses this feature and none has been identified by the contributors to
In this fix an option is added to *enable* the code so that by default
the code is *disabled* - this is a simple generalization of the
suggestion by @sgowdev.
BENEFITS: the problem is eliminated, users of the functionality, if any,
are idenfified, the functionality can be implemented correctly in the
future or it can be removed. Hardly anyone complains.
COSTS: someone will complain that they have to enable an option in a
libpng build to use a feature that never worked consistently in the
first place.
This patch has been tested both with the option enabled and with it
disabled via pngusr.dfa. Tests, checks pass with cmake and configure,
make distcheck passes on configure.
Reported-by: Stephen Gowen <dev.sgowen@gmail.com>
Signed-off-by: John Bowler <jbowler@acm.org>
Signed-off-by: Cosmin Truta <ctruta@gmail.com>
Remove the inclusion of the external module `CMakeParseArguments`.
Function argument parsing became a first-class feature in CMake 3.5.
Delete the function `find_symbol_prefix`. It is no longer used.
Use variables instead of strings in string operations where possible.
Prevent CMake from getting confused by string values that might be
accidentally identical to unrelated keywords.
Clean up spurious `.*` sequences in regex matching operations.
Rephrase a comment.
Fix the issue of a
clang: error: no such file or directory: 'x86_64'
error on building universal binaries on macOS.
It is also necessary to specify:
-DCMAKE_C_FLAGS="-DPNG_ARM_NEON_OPT=0"
Example CMake command:
cmake -S libpng \
-B build_libpng \
-DCMAKE_OSX_ARCHITECTURES="arm64;x86_64" \
-DCMAKE_C_FLAGS="-DPNG_ARM_NEON_OPT=0"
Signed-off-by: Cosmin Truta <ctruta@gmail.com>
Remove all remaining "last changed" version info from source comments.
(The version control system maintains this information automatically.)
Delete the trailing whitespace characters.
Rename contrib/tools/chkfmt to contrib/tools/chkfmt.sh; refactor:
* Increase the max line length for contrib/**/*.[ch] from 96 to 100.
* Set the max line length for ci_*.sh to 100.
* Use `basename $0` instead of the hard-coded script name.
* Update comments.
Remove contrib/tools/reindent. For automated code formatting, including
indentation, we need a robust solution.
Add an empty line after the hashbang line in all scripts.
Remove the "last changed" version info from comment headers.
(The version control system maintains this information automatically.)
