using g++. The compiler imposes C++ rules on the C source; thus it
is desireable to make the source work with either C or C++ rules
without throwing away useful error information. This change adds
png_voidcast to allow C semantic (void*) cases or the corresponding
C++ static_cast operation, as appropriate.
This was because the attempt to reset the zlib stream in png_write_IDAT
happened after the first IDAT chunk had been deflated - much too late.
In this change internal functions are added to claim/release the z_stream
and, hopefully, make the code more robust. Also deflateEnd checking is
added - previously libpng would ignore an error at the end of the stream.
This change adds internal APIs to allow png_warning messages to have parameters
without requiring the host OS to implelment snprintf. As a side effect the
dependency of the RFC1132 code on stdio is removed and PNG_NO_WARNINGS does
actually work now.
the namespace. Added png_get_current_row_number and
png_get_current_pass_number for the
benefit of the user transform callback.
Added png_process_data_pause and png_process_data_skip for the benefit of
progressive readers that need to stop data processing or want to optimize
skipping of unread data (e.g. if the reader marks a chunk to be skipped.)
The changes include support for function attributes in VC in addition to
those already present in GCC - necessary because without these some
warnings are unavoidable. Fixes include signed/unsigned fixes in
pngvalid and checks with gcc -Wall -Wextra -Wunused.
VC requires function attributes on function definitions as well as
declarations, PNG_FUNCTION has been added to enable this and the
relevant function definitions changed.
that were recently introduced, mostly resulting from
safe but uncast assignments to shorter integers. Also added a zlib
VStudio release library project because the latest zlib Official Windows
build does not include such a thing.
Fixed point APIs are now supported throughout (no missing APIs).
Internal fixed point arithmetic support exists for all internal floating
point operations.
sCAL validates the floating point strings it is passed.
Safe, albeit rudimentary, Watcom support is provided by PNG_API_RULE==2
Two new APIs exist to get the number of passes without turning on the
PNG_INTERLACE transform and to get the number of rows in the current
pass.
A new test program, pngvalid.c, validates the gamma code.
Errors in the 16 bit gamma correction (overflows) have been corrected.
cHRM chunk testing is done consistently (previously the floating point
API bypassed it, because the test really didn't work on FP, now the test
is performed on the actual values to be stored in the PNG file so it
works in the FP case too.)
Most floating point APIs now simply call the fixed point APIs after
converting the values to the fixed point form used in the PNG file.
The standard headers no longer include zlib.h, which is currently only
required for pngstruct.h and can therefore be internal.
(Patches by John Bowler)
contrib/pngminim project to pngerror.c, for use when warnings or
errors are disabled via PNG_NO_WARN or PNG_NO_ERROR_TEXT, to avoid
storing unneeded error/warning text.
from the source files, along with "#define PNG_EXPOSE_INTERNAL_STRUCTURES"
and "#define PNG_NO_PEDANTIC_WARNINGS" (John Bowler).
Also created new pngdebug.h and moved debug definitions there.
Added PNG_DEPSTRUCT, PNG_DEPRECATED, PNG_USE_RESULT, PNG_NORETURN, and
PNG_ALLOCATED macros to detect deprecated direct access to the
png_struct or info_struct members and other deprecated usage in
applications (John Bowler).
Added -DPNG_CONFIGURE_LIBPNG to the makefile CFLAGS, to prevent warnings
about direct access to png structs by libpng functions while building
libpng.
Removed three direct references to read_info_ptr members in pngtest.c
that were detected by the new PNG_DEPSTRUCT macro.
Moved the png_debug macro definitions and the png_read_destroy(),
png_write_destroy() and png_far_to_near() prototypes from png.h
to pngpriv.h (John Bowler)
Moved the synopsis lines for png_read_destroy(), png_write_destroy()
png_debug(), png_debug1(), and png_debug2() from libpng.3 to libpngpf.3.
