commit: 965937e274ce7011e32000f606085210a6b83ee5 Author: Matt Jolly <kangie <AT> gentoo <DOT> org> AuthorDate: Sun Feb 22 01:40:44 2026 +0000 Commit: James Le Cuirot <chewi <AT> gentoo <DOT> org> CommitDate: Sun Feb 22 14:01:55 2026 +0000 URL: https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=965937e2
dev-games/libsmacker: add 1.20.0_p43-r1 This commit adds a fix for flickering colours in videos due to palette renderer bailing out, encountered in games-strategy/ja2-stracciatella when using 1.2.0. Signed-off-by: Matt Jolly <kangie <AT> gentoo.org> Part-of: https://github.com/gentoo/gentoo/pull/45850 Signed-off-by: James Le Cuirot <chewi <AT> gentoo.org> .../files/libsmacker-1.2.0-palette_renderer.patch | 63 ++++++++++++++++++++++ .../libsmacker/libsmacker-1.2.0_p43-r1.ebuild | 34 ++++++++++++ 2 files changed, 97 insertions(+) diff --git a/dev-games/libsmacker/files/libsmacker-1.2.0-palette_renderer.patch b/dev-games/libsmacker/files/libsmacker-1.2.0-palette_renderer.patch new file mode 100644 index 000000000000..30560a933bc3 --- /dev/null +++ b/dev-games/libsmacker/files/libsmacker-1.2.0-palette_renderer.patch @@ -0,0 +1,63 @@ +https://github.com/greg-kennedy/libsmacker/pull/2 +From: Matt Jolly <[email protected]> +Date: Sun, 22 Feb 2026 10:30:19 +1000 +Subject: [PATCH] fix: Remove spurious overlap check in palette_render 0x40 + handler + +The colour-shift (0x40) handler in smk_render_palette copies entries +from oldPalette into s->palette: + + memmove(&s->palette[i][0], &oldPalette[src][0], count * 3); + +These are two separate memory regions: oldPalette is a static local +snapshot taken via memcpy at function entry, while s->palette is part +of the smk_video_t struct on the heap. They can never alias. + +Despite this, the bounds check rejects palette deltas where the source +and destination *index* ranges overlap: + + if (src < i && src + count > i) + +This conflates array indices with memory addresses. Since the source +and destination are different buffers, overlapping index ranges are +perfectly valid. + +The result is that any palette delta where a lower-numbered source +entry is copied to a higher-numbered destination entry (encountered in +the wild in e.g. JA2 intro videos) gets incorrectly rejected, causing +smk_render_palette to bail out with an overflow error. Consumers then +see a half-constructed palette, producing corrupted or flickering +colours. + +Commit bea19c1 (2017-01-27, SVN r31) changed palette storage from a flat +malloc'd pointer to an embedded [256][3] array and eliminated the temp +buffer, making the 0x40 handler copy within the same s->palette array. +Commit 2042bd7 (2017-01-27, SVN r32) then correctly added this overlap +guard and switched memcpy to memmove to protect against in-place +forward-copy corruption. Two years later, commit 0464fbb (2019-01-31, +SVN r34) fixed the aliasing problem properly by introducing a static +oldPalette snapshot and reading from that instead, but did not remove +the now-redundant overlap check which has been silently rejecting valid +palette deltas ever since. + +Signed-off-by: Matt Jolly <[email protected]> +--- + smacker.c | 5 ++--- + 1 file changed, 2 insertions(+), 3 deletions(-) + +diff --git a/smacker.c b/smacker.c +index eef6e7b..724b0fe 100644 +--- a/smacker.c ++++ b/smacker.c +@@ -1224,9 +1224,8 @@ static char smk_render_palette(struct smk_video_t * s, unsigned char * p, unsign + p ++; + size --; + +- /* overflow: see if we write/read beyond 256colors, or overwrite own palette */ +- if (i + count > 256 || src + count > 256 || +- (src < i && src + count > i)) { ++ /* overflow: see if we write/read beyond 256 colors */ ++ if (i + count > 256 || src + count > 256) { + fprintf(stderr, "libsmacker::palette_render(s,p,size) - ERROR: overflow, 0x40 attempt to copy %d entries from %d to %d\n", count, src, i); + goto error; + } diff --git a/dev-games/libsmacker/libsmacker-1.2.0_p43-r1.ebuild b/dev-games/libsmacker/libsmacker-1.2.0_p43-r1.ebuild new file mode 100644 index 000000000000..2270b0acf83b --- /dev/null +++ b/dev-games/libsmacker/libsmacker-1.2.0_p43-r1.ebuild @@ -0,0 +1,34 @@ +# Copyright 1999-2026 Gentoo Authors +# Distributed under the terms of the GNU General Public License v2 + +EAPI=9 + +inherit autotools + +DESCRIPTION="A cross-platform C library for decoding .smk Smacker Video files." +HOMEPAGE="https://libsmacker.sourceforge.net"; +SRC_URI="https://sourceforge.net/projects/libsmacker/files/libsmacker-$(ver_cut 1-2)/${P/_p/r}.tar.gz/download -> ${P}.tar.gz" +S="${WORKDIR}/${PN}-$(ver_cut 1-3)" + +LICENSE="LGPL-2.1" +SLOT="0" +KEYWORDS="~amd64 ~arm64 ~ppc64 ~x86" + +src_prepare() { + PATCHES=( + "${FILESDIR}/libsmacker-1.2.0-palette_renderer.patch" + ) + default + eautoreconf +} + +src_install() { + default + + insinto /usr/include + doins smacker.h + + # No .la files or static libraries + find "${ED}" -name '*.la' -delete || die + find "${ED}" -name '*.a' -delete || die +}
