seem to generate warnings when an unsigned value is implicitly
converted to double. This is probably a GCC bug but this change
avoids the issue by explicitly converting to (int) where safe.
Free all allocated memory in pngimage. The file buffer cache was left
allocated at the end of the program, harmless but it causes memory
leak reports from clang.
Fixed array size calculations to avoid warnings. At various points
in the code the number of elements in an array is calculated using
sizeof. This generates a compile time constant of type (size_t) which
is then typically assigned to an (unsigned int) or (int). Some versions
of GCC on 64-bit systems warn about the apparent narrowing, even though
the same compiler does apparently generate the correct, in-range,
numeric constant. This adds appropriate, safe, casts to make the
warnings go away.
Removed "option READ_COMPRESSED_TEXT enables READ_TEXT" from pnglibconf.dfa,
to make it possible to configure a libpng that supports iCCP but not TEXT.
Removed "option WRITE_COMPRESSED_TEXT enables WRITE_TEXT" from pnglibconf.dfa
Only mark text chunks as written after successfully writing them.
to run all the png_handle_*() and depend on them to return if info_ptr == NULL.
This improves the performance of png_read_end(png_ptr, NULL) and makes
it more robust against future programming errors.
PNG_TRANSFORM_* values are always defined in png.h and, because they
are used for both read and write in some cases, it is not reliable
to #if out ones that are totally unsupported. This change adds error
detection in png_read_image() and png_write_image() to do a
png_app_error() if the app requests something that cannot be done
and it adds corresponding code to pngimage.c to handle such options
by not attempting to test them.
function definitions before the place where they are called so that
they can be masde static. Move the intrapixel functions and the
grayscale palette builder out of the png?tran.c files. The latter
isn't a transform function and is no longer used internally, and the
former MNG specific functions are better placed in pngread/pngwrite.c
Fixed 'minimal' builds. Various obviously useful minimal 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.
Enabled WRITE_INVERT and WRITE_PACK in contrib/pngminim/encoder.
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.
fixed Cygwin+MSVC build errors. The ICC profile handling now includes more
checking. Several errors that caused rejection of the profile are now
handled with a warning in such a way that the invalid profiles will be
read by default in release (but not pre-RC) builds but will not be
written by default. The easy part of handling a cHRM chunk is written,
where the ICC profile contains the required data. The more difficult
part plus guessing a gAMA value requires code to pass selected RGB values
through the profile.
control of the unknown handling, corrects the pre-existing bug where
the per-chunk 'keep' setting is ignored and makes it possible to skip
IDAT chunks in the sequential reader (broken in earlier 1.6 versions).
There is a new test program, test-unknown.c, which is a work in progress
(not currently part of the test suite). Comments in the header files now
explain how the unknown handling works.
ignore all unknown chunks and all known chunks except for IHDR, PLTE, tRNS,
IDAT, and IEND. Previously it only meant ignore all unknown chunks, the
same as num_chunks == 0. Revised png_image_skip_unused_chunks() to
provide a list of chunks to be processed instead of a list of chunks to
ignore. Revised contrib/gregbook/readpng2.c accordingly.
on alignment increasing pointer casts when -Wcast-align is passed. This
fixes the cases clang warns about either (pngread.c) by eliminating the
casts from png_bytep to png_uint_16p or, for pngrutil.c where the cast
is previously verified or pngstest.c where it is OK by introducing new
png_aligncast macros to do the cast in a way that clang accepts.
checks. The code now does a png_error if an attempt is made to do the
row initialization twice; this is an application error and it has
serious consequences because the transform data in png_struct is
changed by each call.
This turns on PNG_FLAG_DETECT_UNINITIALIZED to detect app code that
fails to call one of the 'start' routines (not enabled in libpng-1.5
because it is technically an API change, since it did normally work
before.) It also makes duplicate calls to png_read_start_row (an
internal function called at the start of the image read) benign, as
they were before changes to use png_inflate_claim. Somehow webkit is
causing this to happen; this is probably a mis-feature in the zlib
changes so this commit is only a work-round.
default. Also changed some warnings in the iCCP and sRGB handling
from to benign errors. Configuration now makes read benign
errors warnings and write benign errors to errors by default (thus
changing the behavior on read). The simplified API always forces
read benign errors to errors (regardless of the system default, unless
this is disabled in which case the simplified API can't be built.)
functions [rw]util.c. A new shared keyword check routine was also added
and the 'zbuf' is no longer allocated on progressive read. It is now
possible to call png_inflate() incrementally.
read code now claims and releases png_ptr->zstream, like the write code.
The bug whereby the progressive reader failed to release the zstream
is now fixed, all initialization is delayed, and the code checks for
changed parameters on deflate rather than always calling
deflatedEnd/deflateInit.
problems. This is an intermediate check-in that solves the immediate problems
and introduces one performance improvement (avoiding a copy via png_ptr->zbuf.)
Further changes will be made to make ICC profile handling more secure.
Fixed a memory overwrite bug in simplified read of RGB PNG with
non-linear gamma Also bugs in the error checking in pngread.c and changed
quite a lot of the checks in pngstest.c to be correct; either correctly
written or not over-optimistic. The pngstest changes are insufficient to
allow all possible RGB transforms to be passed; pngstest cmppixel needs
to be rewritten to make it clearer which errors it allows and then changed
to permit known inaccuracies.
