Simulator: add the argument to keep the updated images

Add the command line option to select the work directory and save the
updated image files. Because some people might have interested in
getting updated images from an ota file.

Also, fix a minor issue that the destination of package_extract_file
needs to be updated if it's a block device. Otherwise, an unintended
file may be extracted in the callers' directory.

Test: run simulation, run unit tests

Change-Id: Ic6a7db0580bc1748d6e080102e4654da4e41fd8c

tests/unit/host/update_simulator_test.cpp

@@ -93,7 +93,7 @@ static void RunSimulation(std::string_view src_tf, std::string_view ota_package,
 
   // Run the update simulation and check the result.
   TemporaryDir work_dir;
-  BuildInfo build_info(work_dir.path);
+  BuildInfo build_info(work_dir.path, false);
   ASSERT_TRUE(build_info.ParseTargetFile(src_tf, false));
   Updater updater(std::make_unique<SimulatorRuntime>(&build_info));
   ASSERT_TRUE(updater.Init(cmd_pipe.release(), ota_package, false));
@@ -211,7 +211,7 @@ TEST_F(UpdateSimulatorTest, BuildInfo_ParseTargetFile) {
   AddZipEntries(zip_file.release(), entries);
 
   TemporaryDir temp_dir;
-  BuildInfo build_info(temp_dir.path);
+  BuildInfo build_info(temp_dir.path, false);
   ASSERT_TRUE(build_info.ParseTargetFile(zip_file.path, false));
 
   std::map<string, string> expected_result = {

updater/build_info.cpp

@@ -16,6 +16,8 @@
 
 #include "updater/build_info.h"
 
+#include <stdio.h>
+
 #include <set>
 #include <vector>
 
@@ -55,12 +57,23 @@ bool BuildInfo::ParseTargetFile(const std::string_view target_file_path, bool ex
         return false;
       }
 
+      std::string mapped_path = image_file.path;
+      // Rename the images to more readable ones if we want to keep the image.
+      if (keep_images_) {
+        mapped_path = work_dir_ + fstab_info.mount_point + ".img";
+        image_file.release();
+        if (rename(image_file.path, mapped_path.c_str()) != 0) {
+          PLOG(ERROR) << "Failed to rename " << image_file.path << " to " << mapped_path;
+          return false;
+        }
+      }
+
       LOG(INFO) << "Mounted " << fstab_info.mount_point << "\nMapping: " << fstab_info.blockdev_name
-                << " to " << image_file.path;
+                << " to " << mapped_path;
 
       blockdev_map_.emplace(
           fstab_info.blockdev_name,
-          FakeBlockDevice(fstab_info.blockdev_name, fstab_info.mount_point, image_file.path));
+          FakeBlockDevice(fstab_info.blockdev_name, fstab_info.mount_point, mapped_path));
       break;
     }
   }

updater/include/updater/build_info.h

@@ -43,7 +43,8 @@ class FakeBlockDevice {
 // query the information and run the update on host.
 class BuildInfo {
  public:
-  explicit BuildInfo(const std::string_view work_dir) : work_dir_(work_dir) {}
+  BuildInfo(const std::string_view work_dir, bool keep_images)
+      : work_dir_(work_dir), keep_images_(keep_images) {}
   // Returns the value of the build properties.
   std::string GetProperty(const std::string_view key, const std::string_view default_value) const;
   // Returns the path to the mock block device.
@@ -69,4 +70,5 @@ class BuildInfo {
 
   std::list<TemporaryFile> temp_files_;
   std::string work_dir_;  // A temporary directory to store the extracted image files
+  bool keep_images_;
 };

updater/install.cpp

@@ -113,7 +113,7 @@ Value* PackageExtractFileFn(const char* name, State* state,
                         argv.size());
     }
     const std::string& zip_path = args[0];
-    const std::string& dest_path = args[1];
+    std::string dest_path = args[1];
 
     ZipArchiveHandle za = state->updater->GetPackageHandle();
     ZipEntry entry;
@@ -122,6 +122,13 @@ Value* PackageExtractFileFn(const char* name, State* state,
       return StringValue("");
     }
 
+    // Update the destination of package_extract_file if it's a block device. During simulation the
+    // destination will map to a fake file.
+    if (std::string block_device_name = state->updater->FindBlockDeviceName(dest_path);
+        !block_device_name.empty()) {
+      dest_path = block_device_name;
+    }
+
     android::base::unique_fd fd(TEMP_FAILURE_RETRY(
         open(dest_path.c_str(), O_WRONLY | O_CREAT | O_TRUNC, S_IRUSR | S_IWUSR)));
     if (fd == -1) {

updater/update_simulator_main.cpp

@@ -58,12 +58,16 @@ int main(int argc, char** argv) {
   std::string skip_function_file;
   std::string source_target_file;
   std::string package_name;
+  std::string work_dir;
+  bool keep_images = false;
 
   constexpr struct option OPTIONS[] = {
+    { "keep_images", no_argument, nullptr, 0 },
     { "oem_settings", required_argument, nullptr, 0 },
     { "ota_package", required_argument, nullptr, 0 },
     { "skip_functions", required_argument, nullptr, 0 },
     { "source", required_argument, nullptr, 0 },
+    { "work_dir", required_argument, nullptr, 0 },
     { nullptr, 0, nullptr, 0 },
   };
 
@@ -86,6 +90,10 @@ int main(int argc, char** argv) {
       source_target_file = optarg;
     } else if (option_name == "ota_package"s) {
       package_name = optarg;
+    } else if (option_name == "keep_images"s) {
+      keep_images = true;
+    } else if (option_name == "work_dir"s) {
+      work_dir = optarg;
     } else {
       Usage(argv[0]);
       return EXIT_FAILURE;
@@ -129,8 +137,11 @@ int main(int argc, char** argv) {
 
   TemporaryFile cmd_pipe;
   TemporaryDir source_temp_dir;
+  if (work_dir.empty()) {
+    work_dir = source_temp_dir.path;
+  }
 
-  BuildInfo source_build_info(source_temp_dir.path);
+  BuildInfo source_build_info(work_dir, keep_images);
   if (!source_build_info.ParseTargetFile(source_target_file, false)) {
     LOG(ERROR) << "Failed to parse the target file " << source_target_file;
     return EXIT_FAILURE;