We should use `FILE *` instead of `FILE*` or `(FILE*)`, consistently,
as we should for all other pointer types. Moreover, when we refer to
standard stdio file objects in comments and in documentation, we should
use the term "FILE objects" consistently.
Lastly, we clarify in a comment in example.c that `PNG_STDIO_SUPPORTED`
is true only when the stdio support is both available in the system and
accessible in the user's libpng build.
This is a cherry-pick of commit c63c5463903014c904b540216c2784023fb8c1c8
from branch 'libpng18'.
Reviewed-by: John Bowler <jbowler@acm.org>
Signed-off-by: Cosmin Truta <ctruta@gmail.com>
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>
This corrects the checks to that libpng 10800 does not turn on the
enhanced transform checks in either pngvalid or pngstest. The correct
fix is to change the 10700 code for comments which explain what aspect
or aspects of the transforms are broken (ideally) or at least state that
the transforms are broken.
This is a cherry-pick of commit aec888ab80f5d2241b3515b60f0f9337108fb624
from branch 'libpng18'.
Reviewed-by: Cosmin Truta <ctruta@gmail.com>
Signed-off-by: John Bowler <jbowler@acm.org>
Signed-off-by: Cosmin Truta <ctruta@gmail.com>
pngimage.c:
Initialize sig_bits on a NOTREACHED path to avoid warnings about using
uninitialized variables.
pngstest.c:
Enlarge buffers and fix signedness to avoid legitimate warnings about
potential buffer overflows.
pngunknown.c:
pngvalid.c:
Use NULL instead of 0 for pointers and apply other style fixes.
makepng.c:
tarith.c:
Apply various style fixes.
Also remove the "last changed" version info from source comments.
The version control system maintains this information automatically.
As per the const correctness rules, top-level const-ness of data
in automatic scopes does not propagate outside of these scopes
(unlike const-ness at lower levels, such as pointers to const data).
Previously, const was used liberally, but inconsistently across the
libpng codebase. Using const wherever applicable is not incorrect.
However, _consistent_ use of const is difficult to maintain in such
conditions.
In conclusion, we shall continue to use const only where doing so is
strictly necessary:
1. If a function guarantees that it will not modify an argument
passed by pointer, the corresponding function parameter should be
a pointer-to-const (const T *).
2. Static data should not be modified, therefore it should be const.
Reference:
Google C++ Style Guide
https://google.github.io/styleguide/cppguide.html#Use_of_const
In v1.6.0, compiler support for const became a requirement.
It should be used consistently. To maintain backwards compatibility,
PNG_CONST is still maintained in deprecated form.
In v1.6.0, size_t became a required type. It should be used
consistently. To maintain backwards compatibility, png_size_t
is still maintained in deprecated form.
result when integers appear on both sides of a compare. Worked around the
others by forcing the strict-overflow setting in the relevant functions to
a level where they are not reported.
Changed "FALL THROUGH" comments to "FALLTHROUGH" because GCC doesn't like
the space.
Worked around some C-style casts from (void*) because g++ 5.4.0 objects
to them.
Increased the buffer size for 'sprint' to pass the gcc 7.1.0 'sprint
overflow' check that is on by default with -Wall -Wextra.
The SKIP definition needs to come after the png.h include (see all the other .c
files in contrib/libtests) because it depends on PNG_LIBPNG_VER. This commit
puts it in the correct place.
Signed-off-by: John Bowler <jbowler@acm.org>
The macro underreported the size (by up to 512 bytes) of an 8-bit non-color
palette based memory format because it failed to take into account that the
memory palette has to be expanded to full RGB when it is written to PNG.
This is not likely to be a serious bug because the macro is new, the memory
format in question is likely to be rarely used and the result of an undersized
buffer fails in a safe way.
Signed-off-by: John Bowler <jbowler@acm.org>
This implements an API and provides a number of assist macros to allow an
application which uses the simplified API write to bypass stdio and write
directly to memory.
It also includes some warnings (png.h) and some check code to detect *possible*
overflow in the ROW_STRIDE and simplified image SIZE macros. This disallows
image width/height/format that *might* overflow. A quiet API change that limits
in-memory image size (uncompressed) to less that 4GByte and image row size
(stride) to less than 2GByte.
Signed-off-by: John Bowler <jbowler@acm.org>
Splitting the machine generated error structs out to a file allows the values to
be updated without changing pngstest.c itself, since libpng 1.6 and 1.7 have
slightly different error limits this simplifies maintenance.
Signed-off-by: John Bowler <jbowler@acm.org>
handling in contrib/libtests/pngstest.c; possible overflow of
unsigned char in contrib/tools/png-fix-itxt.c). To use the "secure"
file handling, define PNG_USE_MKSTEMP, otherwise "tmpfile()" will
continue to be used.
configurations don't build because of missing contrib/libtests test programs
and overly complex dependencies in scripts/pnglibconf.dfa. This change adds
contrib/conftest/*.dfa files that can be used in automatic build
scripts to ensure that these configurations continue to build.
a flag to change default. In 1.6.0 when the simplified API was used
to produce color-mapped output from an input image with no gamma
information the gamma assumed for the input could be different from
that assumed for non-color-mapped output. In particular 16-bit depth
input files were assumed to be sRGB encoded, whereas in the 'direct'
case they were assumed to have linear data. This was an error. The
fix makes the simplified API treat all input files the same way and
adds a new flag to the png_image::flags member to allow the
application/user to specify that 16-bit files contain sRGB data
rather than the default linear.
Fixed bugs in the pngpixel and makepng test programs.
