Accept a file descriptor to write bugreport file

This will be used via the bugreporting api.

Changed dumpstate to do bugreport generation in its own directory
in the beginning and to copy over to the destination fd or directory
at the very end.

BUG: 111441001
Test: adb bugreport
Test: adb shell /data/nativetest64/dumpstate_test/dumpstate_test
Test: interactive bugreport
Change-Id: I83e24f0989a202e84266b6e0fdf8edc14ea639bf

1 files changed, 148 insertions, 22 deletions

diff --git a/cmds/dumpstate/dumpstate.cpp b/cmds/dumpstate/dumpstate.cpp
index 9a11da626c..0f2996e208 100644
--- a/cmds/dumpstate/dumpstate.cpp
+++ b/cmds/dumpstate/dumpstate.cpp
@@ -82,6 +82,7 @@ using android::String8;
 using android::TIMED_OUT;
 using android::UNKNOWN_ERROR;
 using android::Vector;
+using android::base::StringPrintf;
 using android::os::dumpstate::CommandOptions;
 using android::os::dumpstate::DumpFileToFd;
 using android::os::dumpstate::DumpstateSectionReporter;
@@ -121,6 +122,69 @@ static const std::string ANR_FILE_PREFIX = "anr_";
 
 // TODO: temporary variables and functions used during C++ refactoring
 static Dumpstate& ds = Dumpstate::GetInstance();
+
+namespace android {
+namespace os {
+namespace {
+
+static int Open(std::string path, int flags, mode_t mode = 0) {
+    int fd = TEMP_FAILURE_RETRY(open(path.c_str(), flags, mode));
+    if (fd == -1) {
+        MYLOGE("open(%s, %s)\n", path.c_str(), strerror(errno));
+    }
+    return fd;
+}
+
+static int OpenForWrite(std::string path) {
+    return Open(path, O_WRONLY | O_CREAT | O_TRUNC | O_CLOEXEC | O_NOFOLLOW,
+                S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
+}
+
+static int OpenForRead(std::string path) {
+    return Open(path, O_RDONLY | O_CLOEXEC | O_NOFOLLOW);
+}
+
+bool CopyFile(int in_fd, int out_fd) {
+    char buf[4096];
+    ssize_t byte_count;
+    while ((byte_count = TEMP_FAILURE_RETRY(read(in_fd, buf, sizeof(buf)))) > 0) {
+        if (!android::base::WriteFully(out_fd, buf, byte_count)) {
+            return false;
+        }
+    }
+    return (byte_count != -1);
+}
+
+static bool CopyFileToFd(const std::string& input_file, int out_fd) {
+    MYLOGD("Going to copy bugreport file (%s) to %d\n", ds.path_.c_str(), out_fd);
+
+    // Obtain a handle to the source file.
+    android::base::unique_fd in_fd(OpenForRead(input_file));
+    if (out_fd != -1 && in_fd.get() != -1) {
+        if (CopyFile(in_fd.get(), out_fd)) {
+            return true;
+        }
+        MYLOGE("Failed to copy zip file: %s\n", strerror(errno));
+    }
+    return false;
+}
+
+static bool CopyFileToFile(const std::string& input_file, const std::string& output_file) {
+    if (input_file == output_file) {
+        MYLOGD("Skipping copying bugreport file since the destination is the same (%s)\n",
+               output_file.c_str());
+        return false;
+    }
+
+    MYLOGD("Going to copy bugreport file (%s) to %s\n", input_file.c_str(), output_file.c_str());
+    android::base::unique_fd out_fd(OpenForWrite(output_file));
+    return CopyFileToFd(input_file, out_fd.get());
+}
+
+}  // namespace
+}  // namespace os
+}  // namespace android
+
 static int RunCommand(const std::string& title, const std::vector<std::string>& fullCommand,
                       const CommandOptions& options = CommandOptions::DEFAULT) {
     return ds.RunCommand(title, fullCommand, options);
@@ -137,8 +201,6 @@ static int DumpFile(const std::string& title, const std::string& path) {
 // Relative directory (inside the zip) for all files copied as-is into the bugreport.
 static const std::string ZIP_ROOT_DIR = "FS";
 
-// Must be hardcoded because dumpstate HAL implementation need SELinux access to it
-static const std::string kDumpstateBoardPath = "/bugreports/";
 static const std::string kProtoPath = "proto/";
 static const std::string kProtoExt = ".proto";
 static const std::string kDumpstateBoardFiles[] = {
@@ -1145,7 +1207,7 @@ static void DumpHals() {
                                 return !isalnum(c) &&
                                     std::string("@-_:.").find(c) == std::string::npos;
                             }, '_');
-            const std::string path = kDumpstateBoardPath + "lshal_debug_" + cleanName;
+            const std::string path = ds.bugreport_internal_dir_ + "/lshal_debug_" + cleanName;
 
             {
                 auto fd = android::base::unique_fd(
@@ -1523,7 +1585,8 @@ void Dumpstate::DumpstateBoard() {
     std::vector<std::string> paths;
     std::vector<android::base::ScopeGuard<std::function<void()>>> remover;
     for (int i = 0; i < NUM_OF_DUMPS; i++) {
-        paths.emplace_back(kDumpstateBoardPath + kDumpstateBoardFiles[i]);
+        paths.emplace_back(StringPrintf("%s/%s", ds.bugreport_internal_dir_.c_str(),
+                                        kDumpstateBoardFiles[i].c_str()));
         remover.emplace_back(android::base::make_scope_guard(std::bind(
             [](std::string path) {
                 if (remove(path.c_str()) != 0 && errno != ENOENT) {
@@ -1681,7 +1744,8 @@ bool Dumpstate::FinishZipFile() {
         MYLOGE("Failed to add dumpstate log to .zip file\n");
         return false;
     }
-    // ... and re-opens it for further logging.
+    // TODO: Should truncate the existing file.
+    // ... and re-open it for further logging.
     redirect_to_existing_file(stderr, const_cast<char*>(ds.log_path_.c_str()));
     fprintf(stderr, "\n");
 
@@ -1764,17 +1828,30 @@ static void Vibrate(int duration_ms) {
     // clang-format on
 }
 
+static void MaybeResolveSymlink(std::string* path) {
+    std::string resolved_path;
+    if (android::base::Readlink(*path, &resolved_path)) {
+        *path = resolved_path;
+    }
+}
+
 /*
  * Prepares state like filename, screenshot path, etc in Dumpstate. Also initializes ZipWriter
  * if we are writing zip files and adds the version file.
  */
 static void PrepareToWriteToFile() {
-    ds.bugreport_dir_ = dirname(ds.options_->use_outfile.c_str());
+    MaybeResolveSymlink(&ds.bugreport_internal_dir_);
+
+    std::string base_name_part1 = "bugreport";
+    if (!ds.options_->use_outfile.empty()) {
+        ds.bugreport_dir_ = dirname(ds.options_->use_outfile.c_str());
+        base_name_part1 = basename(ds.options_->use_outfile.c_str());
+    }
+
     std::string build_id = android::base::GetProperty("ro.build.id", "UNKNOWN_BUILD");
     std::string device_name = android::base::GetProperty("ro.product.name", "UNKNOWN_DEVICE");
     ds.base_name_ =
-        android::base::StringPrintf("%s-%s-%s", basename(ds.options_->use_outfile.c_str()),
-                                    device_name.c_str(), build_id.c_str());
+        StringPrintf("%s-%s-%s", base_name_part1.c_str(), device_name.c_str(), build_id.c_str());
     if (ds.options_->do_add_date) {
         char date[80];
         strftime(date, sizeof(date), "%Y-%m-%d-%H-%M-%S", localtime(&ds.now_));
@@ -1795,15 +1872,18 @@ static void PrepareToWriteToFile() {
     ds.tmp_path_ = ds.GetPath(".tmp");
     ds.log_path_ = ds.GetPath("-dumpstate_log-" + std::to_string(ds.pid_) + ".txt");
 
+    std::string destination = ds.options_->fd != -1 ? StringPrintf("[fd:%d]", ds.options_->fd)
+                                                    : ds.bugreport_dir_.c_str();
     MYLOGD(
         "Bugreport dir: %s\n"
+        "Internal Bugreport dir: %s\n"
         "Base name: %s\n"
         "Suffix: %s\n"
         "Log path: %s\n"
         "Temporary path: %s\n"
         "Screenshot path: %s\n",
-        ds.bugreport_dir_.c_str(), ds.base_name_.c_str(), ds.name_.c_str(), ds.log_path_.c_str(),
-        ds.tmp_path_.c_str(), ds.screenshot_path_.c_str());
+        destination.c_str(), ds.bugreport_internal_dir_.c_str(), ds.base_name_.c_str(),
+        ds.name_.c_str(), ds.log_path_.c_str(), ds.tmp_path_.c_str(), ds.screenshot_path_.c_str());
 
     if (ds.options_->do_zip_file) {
         ds.path_ = ds.GetPath(".zip");
@@ -1869,6 +1949,19 @@ static void FinalizeFile() {
                     ds.path_ = new_path;
                 }
             }
+            // The zip file lives in an internal directory. Copy it over to output.
+            bool copy_succeeded = false;
+            if (ds.options_->fd != -1) {
+                copy_succeeded = android::os::CopyFileToFd(ds.path_, ds.options_->fd);
+            } else {
+                ds.final_path_ = ds.GetPath(ds.bugreport_dir_, ".zip");
+                copy_succeeded = android::os::CopyFileToFile(ds.path_, ds.final_path_);
+            }
+            if (copy_succeeded) {
+                if (remove(ds.path_.c_str())) {
+                    MYLOGE("remove(%s): %s", ds.path_.c_str(), strerror(errno));
+                }
+            }
         }
     }
     if (do_text_file) {
@@ -1893,8 +1986,9 @@ static void FinalizeFile() {
 
 /* Broadcasts that we are done with the bugreport */
 static void SendBugreportFinishedBroadcast() {
-    if (!ds.path_.empty()) {
-        MYLOGI("Final bugreport path: %s\n", ds.path_.c_str());
+    // TODO(b/111441001): use callback instead of broadcast.
+    if (!ds.final_path_.empty()) {
+        MYLOGI("Final bugreport path: %s\n", ds.final_path_.c_str());
         // clang-format off
 
         std::vector<std::string> am_args = {
@@ -1902,7 +1996,7 @@ static void SendBugreportFinishedBroadcast() {
              "--ei", "android.intent.extra.ID", std::to_string(ds.id_),
              "--ei", "android.intent.extra.PID", std::to_string(ds.pid_),
              "--ei", "android.intent.extra.MAX", std::to_string(ds.progress_->GetMax()),
-             "--es", "android.intent.extra.BUGREPORT", ds.path_,
+             "--es", "android.intent.extra.BUGREPORT", ds.final_path_,
              "--es", "android.intent.extra.DUMPSTATE_LOG", ds.log_path_
         };
         // clang-format on
@@ -1924,7 +2018,7 @@ static void SendBugreportFinishedBroadcast() {
         if (ds.options_->is_remote_mode) {
             am_args.push_back("--es");
             am_args.push_back("android.intent.extra.REMOTE_BUGREPORT_HASH");
-            am_args.push_back(SHA256_file_hash(ds.path_));
+            am_args.push_back(SHA256_file_hash(ds.final_path_));
             SendBroadcast("com.android.internal.intent.action.REMOTE_BUGREPORT_FINISHED", am_args);
         } else {
             SendBroadcast("com.android.internal.intent.action.BUGREPORT_FINISHED", am_args);
@@ -2054,6 +2148,7 @@ static void LogDumpOptions(const Dumpstate::DumpOptions& options) {
     MYLOGI("telephony_only: %d\n", options.telephony_only);
     MYLOGI("wifi_only: %d\n", options.wifi_only);
     MYLOGI("do_progress_updates: %d\n", options.do_progress_updates);
+    MYLOGI("fd: %d\n", options.fd);
     MYLOGI("use_outfile: %s\n", options.use_outfile.c_str());
     MYLOGI("extra_options: %s\n", options.extra_options.c_str());
     MYLOGI("args: %s\n", options.args.c_str());
@@ -2119,8 +2214,13 @@ Dumpstate::RunStatus Dumpstate::DumpOptions::Initialize(int argc, char* argv[])
 }
 
 bool Dumpstate::DumpOptions::ValidateOptions() const {
-    if ((do_zip_file || do_add_date || do_progress_updates || do_broadcast)
-            && use_outfile.empty()) {
+    if (fd != -1 && !do_zip_file) {
+        return false;
+    }
+
+    bool has_out_file_options = !use_outfile.empty() || fd != -1;
+    if ((do_zip_file || do_add_date || do_progress_updates || do_broadcast) &&
+        !has_out_file_options) {
         return false;
     }
 
@@ -2142,10 +2242,31 @@ void Dumpstate::SetOptions(std::unique_ptr<DumpOptions> options) {
     options_ = std::move(options);
 }
 
+/*
+ * Dumps relevant information to a bugreport based on the given options.
+ *
+ * The bugreport can be dumped to a file or streamed to a socket.
+ *
+ * How dumping to file works:
+ * stdout is redirected to a temporary file. This will later become the main bugreport entry.
+ * stderr is redirected a log file.
+ *
+ * The temporary bugreport is then populated via printfs, dumping contents of files and
+ * output of commands to stdout.
+ *
+ * If zipping, the temporary bugreport file is added to the zip archive. Else it's renamed to final
+ * text file.
+ *
+ * If zipping, a bunch of other files and dumps also get added to the zip archive. The log file also
+ * gets added to the archive.
+ *
+ * Bugreports are first generated in a local directory and later copied to the caller's fd or
+ * directory.
+ */
 Dumpstate::RunStatus Dumpstate::Run() {
+    LogDumpOptions(*options_);
     if (!options_->ValidateOptions()) {
         MYLOGE("Invalid options specified\n");
-        LogDumpOptions(*options_);
         return RunStatus::INVALID_INPUT;
     }
     /* set as high priority, and protect from OOM killer */
@@ -2185,9 +2306,9 @@ Dumpstate::RunStatus Dumpstate::Run() {
 
     // TODO: temporarily set progress until it's part of the Dumpstate constructor
     std::string stats_path =
-        is_redirecting ? android::base::StringPrintf("%s/dumpstate-stats.txt",
-                                                     dirname(options_->use_outfile.c_str()))
-                       : "";
+        is_redirecting
+            ? android::base::StringPrintf("%s/dumpstate-stats.txt", bugreport_internal_dir_.c_str())
+            : "";
     progress_.reset(new Progress(stats_path));
 
     /* gets the sequential id */
@@ -2283,13 +2404,18 @@ Dumpstate::RunStatus Dumpstate::Run() {
     int dup_stdout_fd;
     int dup_stderr_fd;
     if (is_redirecting) {
+        // Redirect stderr to log_path_ for debugging.
         TEMP_FAILURE_RETRY(dup_stderr_fd = dup(fileno(stderr)));
         redirect_to_file(stderr, const_cast<char*>(log_path_.c_str()));
         if (chown(log_path_.c_str(), AID_SHELL, AID_SHELL)) {
             MYLOGE("Unable to change ownership of dumpstate log file %s: %s\n", log_path_.c_str(),
                    strerror(errno));
         }
+
+        // Redirect stdout to tmp_path_. This is the main bugreport entry and will be
+        // moved into zip file later, if zipping.
         TEMP_FAILURE_RETRY(dup_stdout_fd = dup(fileno(stdout)));
+        // TODO: why not write to a file instead of stdout to overcome this problem?
         /* TODO: rather than generating a text file now and zipping it later,
            it would be more efficient to redirect stdout to the zip entry
            directly, but the libziparchive doesn't support that option yet. */
@@ -2364,7 +2490,7 @@ Dumpstate::RunStatus Dumpstate::Run() {
     return RunStatus::OK;
 }
 
-/* Main entry point for dumpstate. */
+/* Main entry point for dumpstate binary. */
 int run_main(int argc, char* argv[]) {
     std::unique_ptr<Dumpstate::DumpOptions> options = std::make_unique<Dumpstate::DumpOptions>();
     Dumpstate::RunStatus status = options->Initialize(argc, argv);
@@ -2376,7 +2502,7 @@ int run_main(int argc, char* argv[]) {
     switch (status) {
         case Dumpstate::RunStatus::OK:
             return 0;
-            break;
+            // TODO(b/111441001): Exit directly in the following cases.
         case Dumpstate::RunStatus::HELP:
             ShowUsageAndExit(0 /* exit code */);
             break;