Initial commit

.github/FUNDING.yml

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+# These are supported funding model platforms
+
+github: [mholt] # Replace with up to 4 GitHub Sponsors-enabled usernames e.g., [user1, user2]
+patreon: # Replace with a single Patreon username
+open_collective: # Replace with a single Open Collective username
+ko_fi: # Replace with a single Ko-fi username
+tidelift: # Replace with a single Tidelift platform-name/package-name e.g., npm/babel
+community_bridge: # Replace with a single Community Bridge project-name e.g., cloud-foundry
+liberapay: # Replace with a single Liberapay username
+issuehunt: # Replace with a single IssueHunt username
+otechie: # Replace with a single Otechie username
+custom: # Replace with up to 4 custom sponsorship URLs e.g., ['link1', 'link2']

.github/ISSUE_TEMPLATE/bug_report.md

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+---
+name: Bug report
+about: For behaviors which violate documentation or cause incorrect results
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+<!--
+This template is for bug reports! (If your issue doesn't fit this template, it's probably a feature request instead.)
+To fill out this template, simply replace these comments with your answers.
+Please do not skip questions; this will slow down the resolution process.
+-->
+
+## What version of the package or command are you using?
+<!-- A commit sha or tag is fine -->
+
+
+## What are you trying to do?
+<!-- Please describe clearly what you are trying to do thoroughly enough so that a reader with no context can repeat the same process. -->
+
+
+## What steps did you take?
+<!-- Explain exactly how we can reproduce this bug; attach sample archive files if relevant -->
+
+
+## What did you expect to happen, and what actually happened instead?
+<!-- Please make it clear what the bug actually is -->
+
+
+## How do you think this should be fixed?
+<!-- Being specific by linking to lines of code and even suggesting changes will yield fastest resolution -->
+
+
+## Please link to any related issues, pull requests, and/or discussion
+<!-- This will help add crucial context to your report -->
+
+
+## Bonus: What do you use this package for, and do you have any other suggestions or feedback?
+<!-- We'd like to know! -->

.github/ISSUE_TEMPLATE/generic-feature-request.md

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+---
+name: Generic feature request
+about: Suggest an idea for this project
+title: ''
+labels: feature request
+assignees: ''
+
+---
+
+<!--
+This issue template is for feature requests! If you are reporting a bug instead, please switch templates.
+To fill this out, simply replace these comments with your answers.
+-->
+
+## What would you like to have changed?
+<!-- Describe the feature or enhancement you are requesting -->
+
+
+## Why is this feature a useful, necessary, and/or important addition to this project?
+<!-- Please justify why this change adds value to the project, considering the added maintenance burden and complexity the change introduces -->
+
+
+## What alternatives are there, or what are you doing in the meantime to work around the lack of this feature?
+<!-- We want to get an idea of what is being done in practice, or how other projects support your feature -->
+
+
+## Please link to any relevant issues, pull requests, or other discussions.
+<!-- This adds crucial context to your feature request and can speed things up -->

.github/ISSUE_TEMPLATE/new-format-request.md

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+---
+name: New format request
+about: Request a new archival or compression format
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+<!--
+This template is specifically for adding support for a new archive or compression format to the library. Please, precisely one format per issue.
+To fill this out, replace these comments with your answers.
+-->
+
+## Introduce the format you are requesting.
+<!-- What is it called, what is it used for, etc? Some background information. -->
+
+
+## What do YOU use this format for?
+<!-- We want to know YOUR specific use cases; why do YOU need this format? -->
+
+
+## What is the format's conventional file extension(s)?
+<!-- Don't overthink this one, it's a simple question. -->
+
+
+## Please link to the format's formal or official specification(s).
+<!-- If there isn't a formal spec, link to the most official documentation for the format. Note that unstandardized formats are less likely to be added unless it is in high-enough demand. -->
+
+
+## Which Go libraries could be used to implement this format?
+<!-- This project itself does not actually implement low-level format reading and writing algorithms, so link to pure-Go libraries that do. Dependencies that use cgo or invoke external commands are not eligible for this project. -->

.github/workflows/macos-latest.yml

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+name: Mac
+
+on: [push, pull_request]
+
+jobs:
+
+  build-and-test:
+
+    strategy:
+      matrix:
+        go-version: [1.23]
+    runs-on: macos-latest
+    steps:
+    - name: Install Go
+      uses: actions/setup-go@v5
+      with:
+        go-version: ${{ matrix.go-version }}
+
+    - name: Checkout code
+      uses: actions/checkout@v4
+
+    - name: Test
+      run: go test -v -race ./...

.github/workflows/ubuntu-latest.yml

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+name: Linux
+
+on: [push, pull_request]
+
+jobs:
+
+  build-and-test:
+
+    strategy:
+      matrix:
+        go-version: [1.23]
+    runs-on: ubuntu-latest
+    steps:
+    - name: Install Go
+      uses: actions/setup-go@v5
+      with:
+        go-version: ${{ matrix.go-version }}
+
+    - name: Checkout code
+      uses: actions/checkout@v4
+
+    - name: Test
+      run: go test -v -race ./...

.github/workflows/windows-latest.yml

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+name: Windows
+
+on: [push, pull_request]
+
+jobs:
+
+  build-and-test:
+
+    strategy:
+      matrix:
+        go-version: [1.23]
+    runs-on: windows-latest
+    steps:
+    - name: Install Go
+      uses: actions/setup-go@v5
+      with:
+        go-version: ${{ matrix.go-version }}
+
+    - name: Checkout code
+      uses: actions/checkout@v4
+
+    - name: Test
+      run: go test -v -race ./...

.gitignore

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+_gitignore

7z.go

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+package archives
+
+import (
+	"bytes"
+	"context"
+	"errors"
+	"fmt"
+	"io"
+	"io/fs"
+	"log"
+	"path"
+	"strings"
+
+	"github.com/bodgit/sevenzip"
+)
+
+func init() {
+	RegisterFormat(SevenZip{})
+
+	// looks like the sevenzip package registers a lot of decompressors for us automatically:
+	// https://github.com/bodgit/sevenzip/blob/46c5197162c784318b98b9a3f80289a9aa1ca51a/register.go#L38-L61
+}
+
+type SevenZip struct {
+	// If true, errors encountered during reading or writing
+	// a file within an archive will be logged and the
+	// operation will continue on remaining files.
+	ContinueOnError bool
+
+	// The password, if dealing with an encrypted archive.
+	Password string
+}
+
+func (z SevenZip) Extension() string { return ".7z" }
+
+func (z SevenZip) Match(_ context.Context, filename string, stream io.Reader) (MatchResult, error) {
+	var mr MatchResult
+
+	// match filename
+	if strings.Contains(strings.ToLower(filename), z.Extension()) {
+		mr.ByName = true
+	}
+
+	// match file header
+	buf, err := readAtMost(stream, len(sevenZipHeader))
+	if err != nil {
+		return mr, err
+	}
+	mr.ByStream = bytes.Equal(buf, sevenZipHeader)
+
+	return mr, nil
+}
+
+// Archive is not implemented for 7z because I do not know of a pure-Go 7z writer.
+
+// Extract extracts files from z, implementing the Extractor interface. Uniquely, however,
+// sourceArchive must be an io.ReaderAt and io.Seeker, which are oddly disjoint interfaces
+// from io.Reader which is what the method signature requires. We chose this signature for
+// the interface because we figure you can Read() from anything you can ReadAt() or Seek()
+// with. Due to the nature of the zip archive format, if sourceArchive is not an io.Seeker
+// and io.ReaderAt, an error is returned.
+func (z SevenZip) Extract(ctx context.Context, sourceArchive io.Reader, handleFile FileHandler) error {
+	sra, ok := sourceArchive.(seekReaderAt)
+	if !ok {
+		return fmt.Errorf("input type must be an io.ReaderAt and io.Seeker because of zip format constraints")
+	}
+
+	size, err := streamSizeBySeeking(sra)
+	if err != nil {
+		return fmt.Errorf("determining stream size: %w", err)
+	}
+
+	zr, err := sevenzip.NewReaderWithPassword(sra, size, z.Password)
+	if err != nil {
+		return err
+	}
+
+	// important to initialize to non-nil, empty value due to how fileIsIncluded works
+	skipDirs := skipList{}
+
+	for i, f := range zr.File {
+		f := f // make a copy for the Open closure
+		if err := ctx.Err(); err != nil {
+			return err // honor context cancellation
+		}
+
+		if fileIsIncluded(skipDirs, f.Name) {
+			continue
+		}
+
+		fi := f.FileInfo()
+		file := FileInfo{
+			FileInfo:      fi,
+			Header:        f.FileHeader,
+			NameInArchive: f.Name,
+			Open: func() (fs.File, error) {
+				openedFile, err := f.Open()
+				if err != nil {
+					return nil, err
+				}
+				return fileInArchive{openedFile, fi}, nil
+			},
+		}
+
+		err := handleFile(ctx, file)
+		if errors.Is(err, fs.SkipDir) {
+			// if a directory, skip this path; if a file, skip the folder path
+			dirPath := f.Name
+			if !file.IsDir() {
+				dirPath = path.Dir(f.Name) + "/"
+			}
+			skipDirs.add(dirPath)
+		} else if err != nil {
+			if z.ContinueOnError {
+				log.Printf("[ERROR] %s: %v", f.Name, err)
+				continue
+			}
+			return fmt.Errorf("handling file %d: %s: %w", i, f.Name, err)
+		}
+	}
+
+	return nil
+}
+
+// https://py7zr.readthedocs.io/en/latest/archive_format.html#signature
+var sevenZipHeader = []byte("7z\xBC\xAF\x27\x1C")
+
+// Interface guard
+var _ Extractor = SevenZip{}

LICENSE

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+MIT License
+
+Copyright (c) 2016 Matthew Holt
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.