From 57bed73721c35971bb1e141901aa23ab50b6269f Mon Sep 17 00:00:00 2001
From: Aly Raffauf <aly@aly.codes>
Date: Fri, 19 Jun 2026 03:34:27 -0400
Subject: [PATCH] better context management for dwarfs

---
 internal/appherder/appimage.go | 7 ++++---
 internal/appherder/dwarfs.go   | 4 ++--
 internal/appherder/install.go  | 8 ++++----
 internal/appherder/sync.go     | 4 ++--
 internal/appherder/upgrade.go  | 2 +-
 5 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/internal/appherder/appimage.go b/internal/appherder/appimage.go
index 34d2f66..a9323f7 100644
--- a/internal/appherder/appimage.go
+++ b/internal/appherder/appimage.go
@@ -1,6 +1,7 @@
 package appherder
 
 import (
+	"context"
 	"encoding/binary"
 	"errors"
 	"fmt"
@@ -17,7 +18,7 @@ import (
 // openAppImage exposes a type-2 AppImage's filesystem as an fs.FS. Supports
 // SquashFS (in-process) and DwarFS (extracted via the runtime). Caller must
 // invoke the returned closer to release resources.
-func openAppImage(path string) (fs.FS, func(), error) {
+func openAppImage(ctx context.Context, path string) (fs.FS, func(), error) {
 	file, err := os.Open(path)
 	if err != nil {
 		return nil, nil, fmt.Errorf("open AppImage %s: %w", path, err)
@@ -31,7 +32,7 @@ func openAppImage(path string) (fs.FS, func(), error) {
 
 	if isDwarFS(file, offset) {
 		file.Close()
-		return openDwarFS(path)
+		return openDwarFS(ctx, path)
 	}
 
 	if isSquashFS(file, offset) {
@@ -280,7 +281,7 @@ func (a App) pruneVersions(dir string, keep int) {
 // readAppImageVersion returns the embedded version string from the AppImage's
 // desktop file, falling back to the file's mtime.
 func readAppImageVersion(path string) string {
-	if fsys, closeFs, err := openAppImage(path); err == nil {
+	if fsys, closeFs, err := openAppImage(context.Background(), path); err == nil {
 		defer closeFs()
 		if desktop, _, err := findDesktopFile(fsys); err == nil && desktop != nil {
 			if version, ok := desktop.Get(desktopEntrySection, "X-AppImage-Version"); ok && version != "" {
diff --git a/internal/appherder/dwarfs.go b/internal/appherder/dwarfs.go
index e3bcabe..b3609b7 100644
--- a/internal/appherder/dwarfs.go
+++ b/internal/appherder/dwarfs.go
@@ -13,14 +13,14 @@ import (
 // openDwarFS extracts the DwarFS payload from an AppImage. Tries the system
 // dwarfsextract tool first; falls back to the AppImage's own --appimage-extract
 // as a last resort. Returns the extracted filesystem and a cleanup function.
-func openDwarFS(appimagePath string) (fs.FS, func(), error) {
+func openDwarFS(ctx context.Context, appimagePath string) (fs.FS, func(), error) {
 	dir, err := os.MkdirTemp("", "appherder-dwarfs")
 	if err != nil {
 		return nil, nil, fmt.Errorf("create temp directory: %w", err)
 	}
 	cleanup := func() { os.RemoveAll(dir) }
 
-	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Minute)
+	ctx, cancel := context.WithTimeout(ctx, 5*time.Minute)
 	defer cancel()
 
 	cmd := extractCommand(ctx, appimagePath, dir)
diff --git a/internal/appherder/install.go b/internal/appherder/install.go
index b8a8d25..0b3a933 100644
--- a/internal/appherder/install.go
+++ b/internal/appherder/install.go
@@ -11,10 +11,10 @@ import (
 )
 
 func (a App) Install(appimage string) (string, error) {
-	return a.install(appimage, expectedChecksum{})
+	return a.install(context.Background(), appimage, expectedChecksum{})
 }
 
-func (a App) install(appimage string, want expectedChecksum) (appName string, err error) {
+func (a App) install(ctx context.Context, appimage string, want expectedChecksum) (appName string, err error) {
 	appimage, err = filepath.Abs(appimage)
 	if err != nil {
 		return "", fmt.Errorf("resolve AppImage path %q: %w", appimage, err)
@@ -28,7 +28,7 @@ func (a App) install(appimage string, want expectedChecksum) (appName string, er
 		return "", err
 	}
 
-	fsys, closeAppImage, err := openAppImage(appimage)
+	fsys, closeAppImage, err := openAppImage(ctx, appimage)
 	if err != nil {
 		return "", err
 	}
@@ -124,7 +124,7 @@ func (a App) InstallFromURL(ctx context.Context, url string) (string, error) {
 		return "", err
 	}
 	defer os.Remove(tmpName)
-	return a.install(tmpName, expectedChecksum{})
+	return a.install(ctx, tmpName, expectedChecksum{})
 }
 
 // deriveAppName picks the canonical install name: the desktop entry's Name
diff --git a/internal/appherder/sync.go b/internal/appherder/sync.go
index c025f24..5ededc2 100644
--- a/internal/appherder/sync.go
+++ b/internal/appherder/sync.go
@@ -57,8 +57,8 @@ func (a App) Sync(ctx context.Context, force bool) (SyncResult, error) {
 	}
 
 	// parallelMap preserves input order, so results stay deterministic.
-	installResults := parallelMap(ctx, files, installConcurrency, func(_ context.Context, f string) SyncInstall {
-		name, err := a.Install(f)
+	installResults := parallelMap(ctx, files, installConcurrency, func(ctx context.Context, f string) SyncInstall {
+		name, err := a.install(ctx, f, expectedChecksum{})
 		return SyncInstall{File: f, AppName: name, Err: err}
 	})
 
diff --git a/internal/appherder/upgrade.go b/internal/appherder/upgrade.go
index d48a772..8806069 100644
--- a/internal/appherder/upgrade.go
+++ b/internal/appherder/upgrade.go
@@ -124,7 +124,7 @@ func (a App) applyUpgrade(ctx context.Context, name string, rel Release) error {
 	}
 	defer os.Remove(tmpName)
 
-	_, err = a.install(tmpName, rel.expectedChecksum())
+	_, err = a.install(ctx, tmpName, rel.expectedChecksum())
 	return err
 }
 
-- 
2.51.2