Adding upstream version 0.0~git20250520.a1d9079+dfsg.

Signed-off-by: Daniel Baumann <daniel@debian.org>

exp/font/font_darwin.go

@@ -0,0 +1,76 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package font
+
+/*
+#cgo darwin LDFLAGS: -framework CoreFoundation -framework CoreText
+#include <CoreFoundation/CFArray.h>
+#include <CoreFoundation/CFBase.h>
+#include <CoreFoundation/CFData.h>
+#include <CoreText/CTFont.h>
+*/
+import "C"
+import "unsafe"
+
+func buildFont(f C.CTFontRef) []byte {
+	ctags := C.CTFontCopyAvailableTables(f, C.kCTFontTableOptionExcludeSynthetic)
+	tagsCount := C.CFArrayGetCount(ctags)
+
+	var tags []uint32
+	var dataRefs []C.CFDataRef
+	var dataLens []uint32
+
+	for i := C.CFIndex(0); i < tagsCount; i++ {
+		tag := (C.CTFontTableTag)((uintptr)(C.CFArrayGetValueAtIndex(ctags, i)))
+		dataRef := C.CTFontCopyTable(f, tag, 0) // retained
+		tags = append(tags, uint32(tag))
+		dataRefs = append(dataRefs, dataRef)
+		dataLens = append(dataLens, uint32(C.CFDataGetLength(dataRef)))
+	}
+
+	totalLen := 0
+	for _, l := range dataLens {
+		totalLen += int(l)
+	}
+
+	// Big-endian output.
+	buf := make([]byte, 0, 12+16*len(tags)+totalLen)
+	write16 := func(x uint16) { buf = append(buf, byte(x>>8), byte(x)) }
+	write32 := func(x uint32) { buf = append(buf, byte(x>>24), byte(x>>16), byte(x>>8), byte(x)) }
+
+	// File format description: http://www.microsoft.com/typography/otspec/otff.htm
+	write32(0x00010000)        // version 1.0
+	write16(uint16(len(tags))) // numTables
+	write16(0)                 // searchRange
+	write16(0)                 // entrySelector
+	write16(0)                 // rangeShift
+
+	// Table tags, includes offsets into following data segments.
+	offset := uint32(12 + 16*len(tags)) // offset starts after table tags
+	for i, tag := range tags {
+		write32(tag)
+		write32(0)
+		write32(offset)
+		write32(dataLens[i])
+		offset += dataLens[i]
+	}
+
+	// Data segments.
+	for i, dataRef := range dataRefs {
+		data := (*[1<<31 - 2]byte)((unsafe.Pointer)(C.CFDataGetBytePtr(dataRef)))[:dataLens[i]]
+		buf = append(buf, data...)
+		C.CFRelease(C.CFTypeRef(dataRef))
+	}
+
+	return buf
+}
+
+func buildDefault() ([]byte, error) {
+	return buildFont(C.CTFontCreateUIFontForLanguage(C.kCTFontSystemFontType, 0, 0)), nil
+}
+
+func buildMonospace() ([]byte, error) {
+	return buildFont(C.CTFontCreateUIFontForLanguage(C.kCTFontUserFixedPitchFontType, 0, 0)), nil
+}