From 10a67fd9f8300c0b9bd9ab9205e21fee01012abe Mon Sep 17 00:00:00 2001
From: Brad Davis <bdavis@saintandreas.org>
Date: Wed, 10 Jan 2018 13:33:43 -0800
Subject: [PATCH] Fix unpack resources on android

---
 android/app/src/main/cpp/native.cpp | 96 ++++++++++++++++++++---------
 1 file changed, 67 insertions(+), 29 deletions(-)

diff --git a/android/app/src/main/cpp/native.cpp b/android/app/src/main/cpp/native.cpp
index 90d8d55af9..c6e3ee2070 100644
--- a/android/app/src/main/cpp/native.cpp
+++ b/android/app/src/main/cpp/native.cpp
@@ -1,3 +1,7 @@
+#include <functional>
+
+
+#include <QtCore/QBuffer>
 #include <QtCore/QDebug>
 #include <QtCore/QDir>
 #include <QtCore/QFile>
@@ -12,6 +16,8 @@
 #include <android/asset_manager.h>
 #include <android/asset_manager_jni.h>
 
+#include <shared/Storage.h>
+
 void tempMessageHandler(QtMsgType type, const QMessageLogContext& context, const QString& message) {
     if (!message.isEmpty()) {
         const char * local=message.toStdString().c_str();
@@ -36,33 +42,65 @@ void tempMessageHandler(QtMsgType type, const QMessageLogContext& context, const
     }
 }
 
-void unpackAndroidAssets() {
-    const QString SOURCE_PREFIX { "assets:/" };
-    const QString DEST_PREFIX = QStandardPaths::writableLocation(QStandardPaths::CacheLocation) + "/";
-    QStringList filesToCopy;
-    QString dateStamp;
-    {
-        QFile file("assets:/cache_assets.txt");
-        if (!file.open(QIODevice::ReadOnly)) {
-            throw std::runtime_error("Failed to open cache file list");
-        }
-        QTextStream in(&file);
-        dateStamp = DEST_PREFIX + "/" + in.readLine();
-        while (!in.atEnd()) {
-            QString line = in.readLine();
-            filesToCopy << line;
-        }
-        file.close();
-    }
-    qDebug() << "Checking date stamp" << dateStamp;
+AAssetManager* g_assetManager = nullptr;
 
-    if (QFileInfo(dateStamp).exists()) {
+void withAssetData(const char* filename, const std::function<void(off64_t, const void*)>& callback) {
+    auto asset = AAssetManager_open(g_assetManager, filename, AASSET_MODE_BUFFER);
+    if (!asset) {
+        throw std::runtime_error("Failed to open file");
+    }
+    auto buffer = AAsset_getBuffer(asset);
+    off64_t size = AAsset_getLength64(asset);
+    callback(size, buffer);
+    AAsset_close(asset);
+}
+
+QStringList readAssetLines(const char* filename) {
+    QStringList result;
+    withAssetData(filename, [&](off64_t size, const void* data){
+        QByteArray buffer = QByteArray::fromRawData((const char*)data, size);
+        {
+            QTextStream in(&buffer);
+            while (!in.atEnd()) {
+                QString line = in.readLine();
+                result << line;
+            }
+        }
+    });
+    return result;
+}
+
+void copyAsset(const char* sourceAsset, const QString& destFilename) {
+    withAssetData(sourceAsset, [&](off64_t size, const void* data){
+        QFile file(destFilename);
+        if (!file.open(QFile::ReadWrite | QIODevice::Truncate)) {
+            throw std::runtime_error("Unable to open output file for writing");
+        }
+        if (!file.resize(size)) {
+            throw std::runtime_error("Unable to resize output file");
+        }
+        auto mapped = file.map(0, size);
+        if (!mapped) {
+            throw std::runtime_error("Unable to map output file");
+        }
+        memcpy(mapped, data, size);
+        file.close();
+    });
+}
+
+void unpackAndroidAssets() {
+    const QString DEST_PREFIX = QStandardPaths::writableLocation(QStandardPaths::CacheLocation) + "/";
+
+    QStringList filesToCopy = readAssetLines("cache_assets.txt");
+    QString dateStamp = filesToCopy.takeFirst();
+    QString dateStampFilename = DEST_PREFIX + dateStamp;
+    qDebug() << "Checking date stamp" << dateStamp;
+    if (QFileInfo(dateStampFilename).exists()) {
         return;
     }
 
     auto rootDir = QDir::root();
     for (const auto& fileToCopy : filesToCopy) {
-        auto sourceFileName = SOURCE_PREFIX + fileToCopy;
         auto destFileName = DEST_PREFIX + fileToCopy;
         auto destFolder = QFileInfo(destFileName).absoluteDir();
         if (!destFolder.exists()) {
@@ -78,19 +116,18 @@ void unpackAndroidAssets() {
             }
         }
 
-        qDebug() << "Copying from" << sourceFileName << "to" << destFileName;
-        if (!QFile(sourceFileName).copy(destFileName)) {
-            throw std::runtime_error("Failed to unpack cache files");
-        }
+        qDebug() << "Copying asset " << fileToCopy << "to" << destFileName;
+        copyAsset(fileToCopy.toStdString().c_str(), destFileName);
     }
 
     {
         qDebug() << "Writing date stamp" << dateStamp;
-        QFile file(dateStamp);
-        if (file.open(QIODevice::ReadWrite)) {
-            QTextStream(&file) << "touch" << endl;
-            file.close();
+        QFile file(dateStampFilename);
+        if (!file.open(QIODevice::ReadWrite | QIODevice::Truncate)) {
+            throw std::runtime_error("Can't write date stamp");
         }
+        QTextStream(&file) << "touch" << endl;
+        file.close();
     }
 }
 
@@ -98,6 +135,7 @@ extern "C" {
 
 JNIEXPORT void Java_io_highfidelity_hifiinterface_InterfaceActivity_nativeOnCreate(JNIEnv* env, jobject obj, jobject instance, jobject asset_mgr) {
     qDebug() << "nativeOnCreate On thread " << QThread::currentThreadId();
+    g_assetManager = AAssetManager_fromJava(env, asset_mgr);
     auto oldMessageHandler = qInstallMessageHandler(tempMessageHandler);
     unpackAndroidAssets();
     qInstallMessageHandler(oldMessageHandler);