Fix null default typeface on Android API 36; remove redundant C APIs#195
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mattleibow merged 2 commits intoApr 25, 2026
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sk_get_default_typeface previously called legacyMakeTypeface("", Normal),
which returns null on Android API 36's SkFontMgr_Android. The subsequent
->ref() in sk_typeface_ref_default crashed with SIGSEGV at offset 0x8
(fault addr 0x8 — the sk_sp internal pointer).
- Drop sk_typeface_ref_default, sk_typeface_create_default,
sk_fontmgr_ref_default, sk_font_new, and the four
sk_typeface_create_from_* functions. The managed binding now owns
default-typeface resolution via SKFontManager.Default.MatchFamily
with a fallback to the new minimal primitive sk_typeface_create_empty.
ABI break — requires a SkiaSharp major version bump.
- Add sk_typeface_create_empty: a thin C API exposing
SkTypeface::MakeEmpty() for managed callers that need a non-null
fallback typeface.
- SkCompatPaint's default constructor now uses SkTypeface::MakeEmpty()
directly. SKPaint's text-via-font surface is already [Obsolete] in
managed — modern callers should use SKFont, which managed always
instantiates with a real typeface handle.
- sk_font_new_with_values now requires a non-null typeface handle
(managed always passes one via SKFont(SKTypeface.Default)).
- Remove the sk_default_fontmgr.{h,cpp} helper module entirely. The
platform-fontmgr selection is now a single #if cascade inside
sk_fontmgr_create_default in sk_typeface.cpp. Managed
SKFontManager.Default is the sole cache of the default font manager.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
SkCompatPaint's default constructor initialized its SkFont with SkTypeface::MakeEmpty, which has zero glyphs. The managed binding compensated by overwriting the font immediately after construction; that dance served no purpose. Require every SkCompatPaint to be constructed with an explicit font, so managed can pass a pinned default SKFont once and rely on SkCompatPaint to copy from it. - Remove SkCompatPaint::SkCompatPaint(). SkCompatPaint(const SkFont*) is now the only forward constructor; copy ctor is unchanged. - SkCompatPaint::reset() becomes reset(const SkFont*): callers provide the reset-to-default font. - Remove sk_compatpaint_new; sk_compatpaint_reset's signature gains a sk_font_t* argument. Update SkiaKeeper to reference sk_compatpaint_new_with_font instead of the removed sk_compatpaint_new. - ABI break — pairs with a managed-side change in SkiaSharp. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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mattleibow
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Apr 24, 2026
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During review, the function was added in commit This was my mistake — I should have pushed the commit to the PR branch (the author's fork) before merging, not to a separate branch on the upstream repo. Fix: #198 cherry-picks the missing commit onto |
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## Context - mono/SkiaSharp#3693 - #195 ## What happened During the review of PR #195, the `sk_fontmgr_legacy_create_typeface` function was added in a separate commit (`e6736d19f`) pushed to a local branch (`dev/issue-3693-legacy-typeface`) on mono/skia — but this commit was **not pushed to the PR author's fork branch**. When PR #195 was squash-merged, only the commits on the fork's branch were included. The separately pushed commit was left behind, so the function that the PR was named after was never actually merged. This was a process error: the fix should have been pushed to the PR branch (on the author's fork) before merging, not to a separate branch on the upstream repo. ## Fix This PR cherry-picks commit `e6736d19f23da0746c4291ed7223e69ffbce3ac1` onto `skiasharp` to add the missing function. ## What the function does `sk_fontmgr_legacy_create_typeface` exposes `SkFontMgr::legacyMakeTypeface()` to the C API. It is needed by SkiaSharp's `SKTypeface.Default` to reliably resolve the platform default typeface on Android, where `matchFamilyStyle(null)` returns null because `onMatchFamily(null)` rejects null family names. `legacyMakeTypeface(null)` bypasses this by using `fDefaultStyleSet` (which searches "sans-serif", "Roboto", then falls back to style set 0). Without this function, `SKTypeface.Default` falls back to the empty typeface on Android API 36, causing all text measurement and drawing to produce zero/nothing.
mattleibow
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Apr 25, 2026
Updates submodule from fb76f3dd84 to f5345469d1 (mono/skia#198). Adds the sk_fontmgr_legacy_create_typeface C API that was missing from the squash merge of mono/skia#195. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
ramezgerges
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Apr 26, 2026
Brings in the latest mono/skia 'skiasharp' branch updates on top of the m147 work-in-progress: * Add variable font C API for typeface variation queries and cloning (mono#185) * Add sk_fontmgr_legacy_create_typeface C API (mono#198, mono#195) — replaces the old sk_default_fontmgr.{cpp,h} with a single C entry point that forwards to SkFontMgr::legacyMakeTypeface(). Fixes the Android default-typeface SIGSEGV. * Use int32_t instead of long for SkManagedStream move offset (mono#186) — fail-loud on overflow instead of silent truncation of platform-dependent C long. * Update libpng to 1.6.58 * Update libexpat to 2.7.5 Conflict resolutions: - DEPS: keep m147's freetype roll, take origin/skiasharp's libexpat 2.7.5 (and libpng 1.6.58 auto-merged the same way). - src/c/sk_default_fontmgr.cpp: accept origin/skiasharp's deletion; their legacyMakeTypeface refactor obviates our m147 carry of that file. - src/c/sk_typeface.cpp: re-apply our m139 SkFontScanner fix to the Android and FontConfig SkFontMgr_New_* call sites, which moved into this file as part of their refactor. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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Description of Change
SkiaSharp Issue
Related to https://github.com/mono/SkiaSharp/issues/
API Changes
Added
sk_typeface_create_empty(void)SkTypeface::MakeEmpty().release()— the minimal non-null primitive the managed binding uses as its fallback.Removed
sk_typeface_create_defaultsk_fontmgr_match_family_style(sk_fontmgr_create_default(), nullptr, &Normal)with a null check + fallback tosk_typeface_create_empty.sk_typeface_ref_defaultsk_typeface_create_from_namesk_fontmgr_match_family_styleonsk_fontmgr_create_default.sk_typeface_create_from_filesk_fontmgr_create_from_fileonsk_fontmgr_create_default.sk_typeface_create_from_streamsk_fontmgr_create_from_streamonsk_fontmgr_create_default.sk_typeface_create_from_datask_fontmgr_create_from_dataonsk_fontmgr_create_default.sk_fontmgr_ref_defaultsk_fontmgr_create_defaultand cache.sk_font_newsk_font_new_with_values(typeface, 12, 1, 0)with a non-null typeface.Internal helpers removed
sk_get_default_typeface— the null-safety logic lives in managed now.sk_get_default_fontmgr— the managed binding is the sole cache.sk_create_default_fontmgr— its body (the#ifcascade selecting a platform fontmgr) is now inlined intosk_fontmgr_create_default.src/c/sk_default_fontmgr.handsrc/c/sk_default_fontmgr.cppdeleted.Contract changes
sk_font_new_with_valuesnow requires a non-nulltypefaceargument. Passingnullptris undefined behavior.SkCompatPaint's default constructor now constructs its backingSkFontwithSkTypeface::MakeEmpty()instead of the platform default.SkCompatPaintexists only to back the deprecatedSKPainttext-rendering surface in the managed binding; modern callers should useSKFontdirectly, which is always constructed with a real typeface.Behavioral Changes
None.
Required SkiaSharp PR
Requires mono/SkiaSharp#3730
PR Checklist
skiasharpat time of PR