mirror of
https://github.com/xiaoqidun/ofdgo.git
synced 2026-10-30 01:27:26 +08:00
266 lines
7.8 KiB
Go
266 lines
7.8 KiB
Go
// Copyright 2025-2026 肖其顿 (XIAO QI DUN)
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
package ofdgo
|
|
|
|
import (
|
|
"bytes"
|
|
"context"
|
|
"encoding/binary"
|
|
"fmt"
|
|
"io"
|
|
"maps"
|
|
"slices"
|
|
)
|
|
|
|
// compactPackageFonts 清理无引用字体，补齐多文档及历史版本的字体裁剪，不修改编辑器快照
|
|
// 入参: ctx 取消上下文, parts 输出修改, removed 待删除条目, generated 本次编码的页面引用
|
|
// 返回: error 读取、结构或取消错误
|
|
func (e *Editor) compactPackageFonts(ctx context.Context, parts map[string][]byte, removed map[string]bool, generated map[string]editorGeneratedReferences) error {
|
|
reader := e.source.reader
|
|
versioned := false
|
|
for _, body := range reader.OFD.DocBody {
|
|
versioned = versioned || body.versioned
|
|
}
|
|
if !versioned {
|
|
if reader.DocumentCount() <= 1 || e.backends.FontResources == nil || e.output != nil && e.output.options.Mode != CompressionUnchanged {
|
|
return nil
|
|
}
|
|
}
|
|
protected, err := reader.hasOutputSignatures(ctx)
|
|
if err != nil || protected {
|
|
return err
|
|
}
|
|
view := &Reader{Zip: reader.Zip, files: maps.Clone(reader.files)}
|
|
if view.files == nil {
|
|
view.files = make(map[string][]byte)
|
|
}
|
|
maps.Copy(view.files, parts)
|
|
if err := view.initRootContext(ctx); err != nil {
|
|
return err
|
|
}
|
|
data, err := view.readFileViewContext(ctx, "OFD.xml")
|
|
if err != nil {
|
|
return err
|
|
}
|
|
root, err := parseEditorXMLContext(ctx, data)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
candidates, seen := make(map[string]bool), make(map[string]bool)
|
|
for _, body := range root.children {
|
|
if err := ctx.Err(); err != nil {
|
|
return err
|
|
}
|
|
if !body.matchesOFD("DocBody") {
|
|
continue
|
|
}
|
|
versions, err := parseVersionEntries(ctx, body)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
for _, entry := range versions {
|
|
version, err := view.readDocumentVersionContext(ctx, entry.ID, entry.Location)
|
|
if err != nil {
|
|
return fmt.Errorf("version %s: %w", entry.ID, err)
|
|
}
|
|
for _, file := range version.Files {
|
|
if err := ctx.Err(); err != nil {
|
|
return err
|
|
}
|
|
name := file.Location
|
|
if seen[name] || removed[name] {
|
|
continue
|
|
}
|
|
seen[name] = true
|
|
candidate, err := view.fontCleanupCandidate(ctx, name)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
if candidate {
|
|
candidates[name] = true
|
|
}
|
|
}
|
|
}
|
|
}
|
|
if err := pruneUnreferencedFiles(ctx, view, slices.Collect(maps.Keys(candidates))...); err != nil {
|
|
return err
|
|
}
|
|
if err := e.subsetPackageFonts(ctx, view, removed, generated); err != nil {
|
|
return err
|
|
}
|
|
for name, data := range view.files {
|
|
if original, ok := reader.files[name]; !ok || !bytes.Equal(original, data) {
|
|
parts[name] = data
|
|
}
|
|
}
|
|
for name := range candidates {
|
|
if !view.fileNames[name] {
|
|
removed[name] = true
|
|
delete(parts, name)
|
|
}
|
|
}
|
|
return nil
|
|
}
|
|
|
|
// fontCleanupCandidate 检查字体目录与文件范围，仅将可识别字体交给引用清理流程
|
|
// 入参: ctx 取消上下文, name 包内文件路径
|
|
// 返回: bool 是否为候选字体, error 读取或取消错误
|
|
func (r *Reader) fontCleanupCandidate(ctx context.Context, name string) (bool, error) {
|
|
input, err := r.openFile(name)
|
|
if err != nil {
|
|
return false, err
|
|
}
|
|
defer input.Close()
|
|
var size uint64
|
|
if data, ok := r.files[cleanPackagePath(name)]; ok {
|
|
size = uint64(len(data))
|
|
} else if file, ok := r.packageFile(name); ok {
|
|
size = file.UncompressedSize64
|
|
}
|
|
candidate, err := fontCleanupDirectory(imageInput{ReadCloser: input, ctx: ctx}, size)
|
|
if err == io.EOF || err == io.ErrUnexpectedEOF {
|
|
err = nil
|
|
}
|
|
if canceled := ctx.Err(); canceled != nil {
|
|
return false, canceled
|
|
}
|
|
return candidate, err
|
|
}
|
|
|
|
// fontCleanupDirectory 检查SFNT表目录或字体集合索引，不读取字形数据
|
|
// 入参: input 文件流, size 文件长度
|
|
// 返回: bool 是否具有有效目录, error 读取错误
|
|
func fontCleanupDirectory(input io.Reader, size uint64) (bool, error) {
|
|
var header [12]byte
|
|
if _, err := io.ReadFull(input, header[:]); err != nil {
|
|
return false, err
|
|
}
|
|
if size < uint64(len(header)) {
|
|
return false, nil
|
|
}
|
|
if string(header[:4]) == "ttcf" {
|
|
version := binary.BigEndian.Uint32(header[4:])
|
|
count := uint64(binary.BigEndian.Uint32(header[8:]))
|
|
if version != 0x00010000 && version != 0x00020000 || count == 0 || count > (size-12)/4 {
|
|
return false, nil
|
|
}
|
|
end := 12 + count*4
|
|
if version == 0x00020000 {
|
|
end += 12
|
|
}
|
|
var entry [4]byte
|
|
for range count {
|
|
if _, err := io.ReadFull(input, entry[:]); err != nil {
|
|
return false, err
|
|
}
|
|
offset := uint64(binary.BigEndian.Uint32(entry[:]))
|
|
if offset < end || offset > size-12 {
|
|
return false, nil
|
|
}
|
|
}
|
|
return true, nil
|
|
}
|
|
switch string(header[:4]) {
|
|
case "\x00\x01\x00\x00", "OTTO", "true":
|
|
default:
|
|
return false, nil
|
|
}
|
|
count := uint64(binary.BigEndian.Uint16(header[4:]))
|
|
if count == 0 || count > (size-12)/16 {
|
|
return false, nil
|
|
}
|
|
end := 12 + count*16
|
|
seen := make(map[uint32]bool, count)
|
|
var entry [16]byte
|
|
for range count {
|
|
if _, err := io.ReadFull(input, entry[:]); err != nil {
|
|
return false, err
|
|
}
|
|
tag := binary.BigEndian.Uint32(entry[:])
|
|
offset := uint64(binary.BigEndian.Uint32(entry[8:]))
|
|
length := uint64(binary.BigEndian.Uint32(entry[12:]))
|
|
if seen[tag] || offset < end || offset > size || length > size-offset {
|
|
return false, nil
|
|
}
|
|
seen[tag] = true
|
|
}
|
|
return true, nil
|
|
}
|
|
|
|
// subsetPackageFonts 按文档作用域收集用字，合并共享字体需求并保留字形编号
|
|
// 入参: ctx 取消上下文, view 独立输出快照, removed 待删除条目, generated 本次编码的页面引用
|
|
// 返回: error 读取、裁剪或取消错误
|
|
func (e *Editor) subsetPackageFonts(ctx context.Context, view *Reader, removed map[string]bool, generated map[string]editorGeneratedReferences) error {
|
|
if e.backends.FontResources == nil {
|
|
return nil
|
|
}
|
|
names := maps.Clone(view.fileNames)
|
|
for name := range removed {
|
|
delete(names, name)
|
|
}
|
|
progress := editorProgress(e.OnWriteProgress)
|
|
refs, resources, references, safe, err := scanEditorResources(ctx, view, view.files, generated, names, progress, true)
|
|
if err != nil || !safe {
|
|
return err
|
|
}
|
|
scoped, err := resourceReferenceScopes(ctx, refs.documents, resources, references, "")
|
|
if err != nil || scoped == nil {
|
|
return err
|
|
}
|
|
read := func(name string) ([]byte, error) { return view.readFileViewContext(ctx, name) }
|
|
usage, err := resourceFontUsage(ctx, resources, scoped, read)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
for _, source := range references {
|
|
for name := range source.files {
|
|
if font := usage[name]; font != nil && !source.versions[name] {
|
|
font.unsafe = true
|
|
}
|
|
}
|
|
for _, definition := range source.definitions {
|
|
for name := range definition.files {
|
|
if font := usage[name]; font != nil {
|
|
font.unsafe = true
|
|
}
|
|
}
|
|
}
|
|
}
|
|
var cache editorSourceFontCache
|
|
for index, name := range slices.Sorted(maps.Keys(usage)) {
|
|
if err := progress.report("fonts", index, len(usage)); err != nil {
|
|
return err
|
|
}
|
|
if usage[name].unsafe || len(usage[name].chars)+len(usage[name].glyphs) == 0 {
|
|
continue
|
|
}
|
|
data, err := read(name)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
subset, err := cache.subset(ctx, e.backends.FontResources, data, usage[name])
|
|
if err != nil {
|
|
return err
|
|
}
|
|
if subset != nil {
|
|
view.files[name] = subset
|
|
}
|
|
}
|
|
if err := progress.report("fonts", len(usage), len(usage)); err != nil {
|
|
return err
|
|
}
|
|
return ctx.Err()
|
|
}
|