gdImageTrueColorToPalette() is sometimes wasteful by putting multiple white
color entries into the palette. This is caused by an obvious typo, where
to avoid a division by zero when `total` is zero, `count` is checked instead
of `total`.
We fix this issue to improve the quality of the color quantization.
Cf. <https://github.com/libgd/libgd/commit/24b4550f>
No pixel of a filled arc must ever be drawn multiple times. Otherwise we get
artifacts regarding transparency. That happens with the current
implementation of gdImageFilledArc() unless gdChord or gdNoFill are set.
When gdPie is set, however, the filled arc is drawn in wedges, which are
polygons of three points, and so some overlap is natural.
To resolve the issue, we stick with the current algorithm of calculating the
wedges, but instead of drawing each polygon separately, we put the relevant
points in a large array, and draw a single polygon. That also is supposed to
improve the performance considerably.
Note that this modification will change the results when gdImageSetStyle()
or gdImageSetBrush() are used, but we believe that this modification is also
an improvement in this regard, even though it still might not make much
sense to use these functions with gdImageFilledArc().
The respective fix for libgd is
<https://github.com/libgd/libgd/commit/e7e20d6>.
* PHP-5.6:
fix#72519, possible OOB using imagegif
fix#72512, invalid read or write for palette image when invalid transparent index is used
Apparently some envs miss SIZE_MAX
Fix tests
Fix bug #72618: NULL Pointer Dereference in exif_process_user_comment
Partial fix for bug #72613 - do not treat negative returns from bz2 as size_t
Fix bug #72606: heap-buffer-overflow (write) simplestring_addn simplestring.c
Fix for bug #72558, Integer overflow error within _gdContributionsAlloc()
Fix bug #72603: Out of bound read in exif_process_IFD_in_MAKERNOTE
Fix bug #72562 - destroy var_hash properly
Fix bug #72533 (locale_accept_from_http out-of-bounds access)
Fix fir bug #72520
Fix for bug #72513
Fix for bug #72513
CS fix and comments with bug ID
Fix for HTTP_PROXY issue.
5.6.24RC1
add tests for bug #72512
Fixed bug #72512 gdImageTrueColorToPaletteBody allows arbitrary write/read access
Fixed bug #72479 - same as #72434
Conflicts:
Zend/zend_virtual_cwd.c
ext/bz2/bz2.c
ext/exif/exif.c
ext/session/session.c
ext/snmp/snmp.c
ext/standard/basic_functions.c
main/SAPI.c
main/php_variables.c
* PHP-5.5:
fix#72519, possible OOB using imagegif
fix#72512, invalid read or write for palette image when invalid transparent index is used
Apparently some envs miss SIZE_MAX
Fix tests
Fix bug #72618: NULL Pointer Dereference in exif_process_user_comment
Partial fix for bug #72613 - do not treat negative returns from bz2 as size_t
Fix bug #72606: heap-buffer-overflow (write) simplestring_addn simplestring.c
Fix for bug #72558, Integer overflow error within _gdContributionsAlloc()
Fix bug #72603: Out of bound read in exif_process_IFD_in_MAKERNOTE
Fix bug #72562 - destroy var_hash properly
Fix bug #72533 (locale_accept_from_http out-of-bounds access)
Fix fir bug #72520
Fix for bug #72513
CS fix and comments with bug ID
Fix for HTTP_PROXY issue.
add tests for bug #72512
Fixed bug #72512 gdImageTrueColorToPaletteBody allows arbitrary write/read access
Fixed bug #72479 - same as #72434
Conflicts:
ext/bz2/bz2.c
main/SAPI.c
main/php_variables.c
Christoph M. Becker