diff --git a/libs/androidfw/Android.bp b/libs/androidfw/Android.bp
index c80fb18..86e1fe3d 100644
--- a/libs/androidfw/Android.bp
+++ b/libs/androidfw/Android.bp
@@ -80,7 +80,10 @@
     export_include_dirs: ["include"],
     export_shared_lib_headers: ["libz"],
     static_libs: ["libincfs-utils"],
-    whole_static_libs: ["libincfs-utils"],
+    whole_static_libs: [
+        "libandroidfw_pathutils",
+        "libincfs-utils",
+    ],
     export_static_lib_headers: ["libincfs-utils"],
     target: {
         android: {
@@ -132,6 +135,28 @@
     },
 }
 
+cc_library_static {
+    name: "libandroidfw_pathutils",
+    defaults: ["libandroidfw_defaults"],
+    host_supported: true,
+    export_include_dirs: ["include_pathutils"],
+    srcs: [
+        "PathUtils.cpp",
+    ],
+    shared_libs: [
+        "libutils",
+    ],
+    target: {
+        windows: {
+            enabled: true,
+        },
+    },
+    visibility: [
+        ":__subpackages__",
+        "//frameworks/base/tools/aapt",
+    ],
+}
+
 common_test_libs = [
     "libandroidfw",
     "libbase",
diff --git a/libs/androidfw/AssetManager.cpp b/libs/androidfw/AssetManager.cpp
index 795bb3c..fd6e18e 100644
--- a/libs/androidfw/AssetManager.cpp
+++ b/libs/androidfw/AssetManager.cpp
@@ -26,6 +26,7 @@
 #include <androidfw/AssetDir.h>
 #include <androidfw/AssetManager.h>
 #include <androidfw/misc.h>
+#include <androidfw/PathUtils.h>
 #include <androidfw/ResourceTypes.h>
 #include <androidfw/ZipFileRO.h>
 #include <cutils/atomic.h>
@@ -88,7 +89,7 @@
     const char* root = getenv("ANDROID_DATA");
     LOG_ALWAYS_FATAL_IF(root == NULL, "ANDROID_DATA not set");
     String8 path(root);
-    path.appendPath(kResourceCache);
+    appendPath(path, kResourceCache);
 
     char buf[256]; // 256 chars should be enough for anyone...
     strncpy(buf, pkgPath.c_str(), 255);
@@ -104,7 +105,7 @@
         }
         ++p;
     }
-    path.appendPath(filename);
+    appendPath(path, filename);
     path.append("@idmap");
 
     return path;
@@ -181,7 +182,7 @@
 
     String8 realPath(path);
     if (kAppZipName) {
-        realPath.appendPath(kAppZipName);
+        appendPath(realPath, kAppZipName);
     }
     ap.type = ::getFileType(realPath.c_str());
     if (ap.type == kFileTypeRegular) {
@@ -367,7 +368,7 @@
     LOG_ALWAYS_FATAL_IF(root == NULL, "ANDROID_ROOT not set");
 
     String8 path(root);
-    path.appendPath(kSystemAssets);
+    appendPath(path, kSystemAssets);
 
     return addAssetPath(path, NULL, false /* appAsLib */, true /* isSystemAsset */);
 }
@@ -439,7 +440,7 @@
     LOG_FATAL_IF(mAssetPaths.size() == 0, "No assets added to AssetManager");
 
     String8 assetName(kAssetsRoot);
-    assetName.appendPath(fileName);
+    appendPath(assetName, fileName);
 
     /*
      * For each top-level asset path, search for the asset.
@@ -587,8 +588,8 @@
                 const char* data = getenv("ANDROID_DATA");
                 LOG_ALWAYS_FATAL_IF(data == NULL, "ANDROID_DATA not set");
                 String8 overlaysListPath(data);
-                overlaysListPath.appendPath(kResourceCache);
-                overlaysListPath.appendPath("overlays.list");
+                appendPath(overlaysListPath, kResourceCache);
+                appendPath(overlaysListPath, "overlays.list");
                 addSystemOverlays(overlaysListPath.c_str(), ap.path, sharedRes, nextEntryIdx);
 #endif
                 sharedRes = const_cast<AssetManager*>(this)->
@@ -789,7 +790,7 @@
     /* look at the filesystem on disk */
     if (ap.type == kFileTypeDirectory) {
         String8 path(ap.path);
-        path.appendPath(fileName);
+        appendPath(path, fileName);
 
         pAsset = openAssetFromFileLocked(path, mode);
 
@@ -841,9 +842,9 @@
     sourceName.append(zipFileName);
     sourceName.append(":");
     if (dirName.length() > 0) {
-        sourceName.appendPath(dirName);
+        appendPath(sourceName, dirName);
     }
-    sourceName.appendPath(fileName);
+    appendPath(sourceName, fileName);
     return sourceName;
 }
 
@@ -853,7 +854,7 @@
 String8 AssetManager::createPathNameLocked(const asset_path& ap, const char* rootDir)
 {
     String8 path(ap.path);
-    if (rootDir != NULL) path.appendPath(rootDir);
+    if (rootDir != NULL) appendPath(path, rootDir);
     return path;
 }
 
@@ -897,7 +898,7 @@
 {
     Asset* pAsset = NULL;
 
-    if (strcasecmp(pathName.getPathExtension().c_str(), ".gz") == 0) {
+    if (strcasecmp(getPathExtension(pathName).c_str(), ".gz") == 0) {
         //printf("TRYING '%s'\n", (const char*) pathName);
         pAsset = Asset::createFromCompressedFile(pathName.c_str(), mode);
     } else {
@@ -1078,8 +1079,7 @@
     //printf("scanAndMergeDir: %s %s %s\n", ap.path.c_str(), rootDir, dirName);
 
     String8 path = createPathNameLocked(ap, rootDir);
-    if (dirName[0] != '\0')
-        path.appendPath(dirName);
+    if (dirName[0] != '\0') appendPath(path, dirName);
 
     SortedVector<AssetDir::FileInfo>* pContents = scanDirLocked(path);
     if (pContents == NULL)
@@ -1176,7 +1176,7 @@
             fileType = kFileTypeUnknown;
 #else
         // stat the file
-        fileType = ::getFileType(path.appendPathCopy(entry->d_name).c_str());
+        fileType = ::getFileType(appendPathCopy(path, entry->d_name).c_str());
 #endif
 
         if (fileType != kFileTypeRegular && fileType != kFileTypeDirectory)
@@ -1184,9 +1184,9 @@
 
         AssetDir::FileInfo info;
         info.set(String8(entry->d_name), fileType);
-        if (strcasecmp(info.getFileName().getPathExtension().c_str(), ".gz") == 0)
-            info.setFileName(info.getFileName().getBasePath());
-        info.setSourceName(path.appendPathCopy(info.getFileName()));
+        if (strcasecmp(getPathExtension(info.getFileName()).c_str(), ".gz") == 0)
+            info.setFileName(getBasePath(info.getFileName()));
+        info.setSourceName(appendPathCopy(path, info.getFileName()));
         pContents->add(info);
     }
 
@@ -1220,7 +1220,7 @@
 
     /* convert "sounds" to "rootDir/sounds" */
     if (rootDir != NULL) dirName = rootDir;
-    dirName.appendPath(baseDirName);
+    appendPath(dirName, baseDirName);
 
     /*
      * Scan through the list of files, looking for a match.  The files in
@@ -1269,7 +1269,7 @@
             if (nextSlash == NULL) {
                 /* this is a file in the requested directory */
 
-                info.set(String8(nameBuf).getPathLeaf(), kFileTypeRegular);
+                info.set(getPathLeaf(String8(nameBuf)), kFileTypeRegular);
 
                 info.setSourceName(
                     createZipSourceNameLocked(zipName, dirName, info.getFileName()));
diff --git a/libs/androidfw/BackupHelpers.cpp b/libs/androidfw/BackupHelpers.cpp
index 3582609..1a6a952 100644
--- a/libs/androidfw/BackupHelpers.cpp
+++ b/libs/androidfw/BackupHelpers.cpp
@@ -30,6 +30,7 @@
 #include <utime.h>
 #include <zlib.h>
 
+#include <androidfw/PathUtils.h>
 #include <log/log.h>
 #include <utils/ByteOrder.h>
 #include <utils/KeyedVector.h>
@@ -606,14 +607,14 @@
             prefix += packageName;
         }
         if (domain.length() > 0) {
-            prefix.appendPath(domain);
+            appendPath(prefix, domain);
         }
 
         // pax extended means we don't put in a prefix field, and put a different
         // string in the basic name field.  We can also construct the full path name
         // out of the substrings we've now built.
         fullname = prefix;
-        fullname.appendPath(relpath);
+        appendPath(fullname, relpath);
 
         // ustar:
         //    [   0 : 100 ]; file name/path
@@ -654,7 +655,7 @@
         // Now build the pax *header* templated on the ustar header
         memcpy(paxHeader, buf, 512);
 
-        String8 leaf = fullname.getPathLeaf();
+        String8 leaf = getPathLeaf(fullname);
         memset(paxHeader, 0, 100);                  // rewrite the name area
         snprintf(paxHeader, 100, "PaxHeader/%s", leaf.c_str());
         memset(paxHeader + 345, 0, 155);            // rewrite the prefix area
diff --git a/libs/androidfw/PathUtils.cpp b/libs/androidfw/PathUtils.cpp
new file mode 100644
index 0000000..df7a9f0
--- /dev/null
+++ b/libs/androidfw/PathUtils.cpp
@@ -0,0 +1,135 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * 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.
+ */
+
+#include <androidfw/PathUtils.h>
+
+#include <utils/Compat.h>
+
+namespace android {
+
+String8 getPathLeaf(const String8& str) {
+    const char* cp;
+    const char*const buf = str.c_str();
+
+    cp = strrchr(buf, OS_PATH_SEPARATOR);
+    if (cp == nullptr)
+        return str;
+    else
+        return String8(cp+1);
+}
+
+String8 getPathDir(const String8& str8) {
+    const char* cp;
+    const char*const str = str8.c_str();
+
+    cp = strrchr(str, OS_PATH_SEPARATOR);
+    if (cp == nullptr)
+        return String8();
+    else
+        return String8(str, cp - str);
+}
+
+static char* findExtension(const String8& str8) {
+    const char* lastSlash;
+    const char* lastDot;
+    const char* const str = str8.c_str();
+
+    // only look at the filename
+    lastSlash = strrchr(str, OS_PATH_SEPARATOR);
+    if (lastSlash == nullptr)
+        lastSlash = str;
+    else
+        lastSlash++;
+
+    // find the last dot
+    lastDot = strrchr(lastSlash, '.');
+    if (lastDot == nullptr)
+        return nullptr;
+
+    // looks good, ship it
+    return const_cast<char*>(lastDot);
+}
+
+String8 getPathExtension(const String8& str) {
+    char* ext;
+
+    ext = findExtension(str);
+    if (ext != nullptr)
+        return String8(ext);
+    else
+        return String8();
+}
+
+String8 getBasePath(const String8& str8) {
+    char* ext;
+    const char* const str = str8.c_str();
+
+    ext = findExtension(str8);
+    if (ext == nullptr)
+        return str8;
+    else
+        return String8(str, ext - str);
+}
+
+static void setPathName(String8& s, const char* name) {
+    size_t len = strlen(name);
+    char* buf = s.lockBuffer(len);
+
+    memcpy(buf, name, len);
+
+    // remove trailing path separator, if present
+    if (len > 0 && buf[len - 1] == OS_PATH_SEPARATOR) len--;
+    buf[len] = '\0';
+
+    s.unlockBuffer(len);
+}
+
+String8& appendPath(String8& str, const char* name) {
+    // TODO: The test below will fail for Win32 paths. Fix later or ignore.
+    if (name[0] != OS_PATH_SEPARATOR) {
+        if (*name == '\0') {
+            // nothing to do
+            return str;
+        }
+
+        size_t len = str.length();
+        if (len == 0) {
+            // no existing filename, just use the new one
+            setPathName(str, name);
+            return str;
+        }
+
+        // make room for oldPath + '/' + newPath
+        int newlen = strlen(name);
+
+        char* buf = str.lockBuffer(len+1+newlen);
+
+        // insert a '/' if needed
+        if (buf[len-1] != OS_PATH_SEPARATOR)
+            buf[len++] = OS_PATH_SEPARATOR;
+
+        memcpy(buf+len, name, newlen+1);
+        len += newlen;
+
+        str.unlockBuffer(len);
+        return str;
+    } else {
+        setPathName(str, name);
+        return str;
+    }
+}
+
+} // namespace android
diff --git a/libs/androidfw/include_pathutils/androidfw/PathUtils.h b/libs/androidfw/include_pathutils/androidfw/PathUtils.h
new file mode 100644
index 0000000..4debe8d
--- /dev/null
+++ b/libs/androidfw/include_pathutils/androidfw/PathUtils.h
@@ -0,0 +1,98 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * 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.
+ */
+
+#pragma once
+
+#include <utils/String8.h>
+
+/* This library contains path manipulation functions that are used only by androidfw and aapt.
+ * When it's possible, migrate all uses to std::filesystem::path.
+ */
+
+namespace android {
+
+/**
+ * Get just the filename component.
+ *
+ * DEPRECATED: use std::filesystem::path::filename
+ *
+ * "/tmp/foo/bar.c" --> "bar.c"
+ */
+String8 getPathLeaf(const String8& str);
+
+/**
+ * Remove the last (file name) component, leaving just the directory
+ * name.
+ *
+ * DEPRECATED: use std::filesystem::path::parent_path
+ *
+ * "/tmp/foo/bar.c" --> "/tmp/foo"
+ * "/tmp" --> "" // ????? shouldn't this be "/" ???? XXX
+ * "bar.c" --> ""
+ */
+String8 getPathDir(const String8& str);
+
+/**
+ * Return the filename extension.  This is the last '.' and any number
+ * of characters that follow it.  The '.' is included in case we
+ * decide to expand our definition of what constitutes an extension.
+ *
+ * DEPRECATED: use std::filesystem::path::extension
+ *
+ * "/tmp/foo/bar.c" --> ".c"
+ * "/tmp" --> ""
+ * "/tmp/foo.bar/baz" --> ""
+ * "foo.jpeg" --> ".jpeg"
+ * "foo." --> ""
+ */
+String8 getPathExtension(const String8& str);
+
+/**
+ * Return the path without the extension.  Rules for what constitutes
+ * an extension are described in the comment for getPathExtension().
+ *
+ * DEPRECATED: use std::filesystem::path::stem and std::filesystem::path::parent_path
+ *
+ * "/tmp/foo/bar.c" --> "/tmp/foo/bar"
+ */
+String8 getBasePath(const String8& str);
+
+/**
+ * Add a component to the pathname.  We guarantee that there is
+ * exactly one path separator between the old path and the new.
+ * If there is no existing name, we just copy the new name in.
+ *
+ * DEPRECATED: use std::filesystem::path::operator/=
+ *
+ * If leaf is a fully qualified path (i.e. starts with '/', it
+ * replaces whatever was there before.
+ */
+String8& appendPath(String8& str, const char* leaf);
+inline String8& appendPath(String8& str, const String8& leaf) {
+    return appendPath(str, leaf.c_str());
+}
+
+/**
+ * Like appendPath(), but does not affect this string.  Returns a new one instead.
+ *
+ * DEPRECATED: use std::filesystem::operator/
+ */
+inline String8 appendPathCopy(String8 str, const char* leaf) { return appendPath(str, leaf); }
+inline String8 appendPathCopy(String8 str, const String8& leaf) {
+    return appendPath(str, leaf.c_str());
+}
+
+} // namespace android