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

4 files changed, 187 insertions, 35 deletions

diff --git a/cmds/dumpstate/DumpstateService.cpp b/cmds/dumpstate/DumpstateService.cpp
index 0ee6c3adac..f2678ebaa4 100644
--- a/cmds/dumpstate/DumpstateService.cpp
+++ b/cmds/dumpstate/DumpstateService.cpp
@@ -137,6 +137,7 @@ status_t DumpstateService::dump(int fd, const Vector<String16>&) {
     dprintf(fd, "extra_options: %s\n", ds_.options_->extra_options.c_str());
     dprintf(fd, "version: %s\n", ds_.version_.c_str());
     dprintf(fd, "bugreport_dir: %s\n", ds_.bugreport_dir_.c_str());
+    dprintf(fd, "bugreport_internal_dir_: %s\n", ds_.bugreport_internal_dir_.c_str());
     dprintf(fd, "screenshot_path: %s\n", ds_.screenshot_path_.c_str());
     dprintf(fd, "log_path: %s\n", ds_.log_path_.c_str());
     dprintf(fd, "tmp_path: %s\n", ds_.tmp_path_.c_str());
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;
diff --git a/cmds/dumpstate/dumpstate.h b/cmds/dumpstate/dumpstate.h
index 35cbdb1096..94e3191087 100644
--- a/cmds/dumpstate/dumpstate.h
+++ b/cmds/dumpstate/dumpstate.h
@@ -142,7 +142,7 @@ class Progress {
     float growth_factor_;
     int32_t n_runs_;
     int32_t average_max_;
-    const std::string& path_;
+    std::string path_;
 };
 
 /*
@@ -164,6 +164,11 @@ static std::string VERSION_SPLIT_ANR = "3.0-dev-split-anr";
 static std::string VERSION_DEFAULT = "default";
 
 /*
+ * Directory used by Dumpstate binary to keep its local files.
+ */
+static const std::string DUMPSTATE_DIRECTORY = "/bugreports";
+
+/*
  * Structure that contains the information of an open dump file.
  */
 struct DumpData {
@@ -300,7 +305,11 @@ class Dumpstate {
      */
     bool FinishZipFile();
 
-    /* Gets the path of a bugreport file with the given suffix. */
+    /* Constructs a full path inside directory with file name formatted using the given suffix. */
+    std::string GetPath(const std::string& directory, const std::string& suffix) const;
+
+    /* Constructs a full path inside bugreport_internal_dir_ with file name formatted using the
+     * given suffix. */
     std::string GetPath(const std::string& suffix) const;
 
     /* Returns true if the current version supports priority dump feature. */
@@ -314,7 +323,6 @@ class Dumpstate {
     /* Sets runtime options. */
     void SetOptions(std::unique_ptr<DumpOptions> options);
 
-    // TODO: add other options from DumpState.
     /*
      * Structure to hold options that determine the behavior of dumpstate.
      */
@@ -333,6 +341,10 @@ class Dumpstate {
         bool wifi_only = false;
         // Whether progress updates should be published.
         bool do_progress_updates = false;
+        // File descriptor to output zip file. -1 indicates not set. Takes precedence over
+        // use_outfile.
+        int fd = -1;
+        // Partial path to output file.
         std::string use_outfile;
         // TODO: rename to MODE.
         // Extra options passed as system property.
@@ -381,12 +393,6 @@ class Dumpstate {
     // Bugreport format version;
     std::string version_ = VERSION_CURRENT;
 
-    // Full path of the directory where the bugreport files will be written.
-    std::string bugreport_dir_;
-
-    // Full path of the temporary file containing the screenshot (when requested).
-    std::string screenshot_path_;
-
     time_t now_;
 
     // Base name (without suffix or extensions) of the bugreport files, typically
@@ -397,15 +403,30 @@ class Dumpstate {
     // `-d`), but it could be changed by the user..
     std::string name_;
 
-    // Full path of the temporary file containing the bugreport.
+    std::string bugreport_internal_dir_ = DUMPSTATE_DIRECTORY;
+
+    // Full path of the temporary file containing the bugreport, inside bugreport_internal_dir_.
+    // At the very end this file is pulled into the zip file.
     std::string tmp_path_;
 
-    // Full path of the file containing the dumpstate logs.
+    // Full path of the file containing the dumpstate logs, inside bugreport_internal_dir_.
+    // This is useful for debugging.
     std::string log_path_;
 
-    // Pointer to the actual path, be it zip or text.
+    // Full path of the bugreport file, be it zip or text, inside bugreport_internal_dir_.
     std::string path_;
 
+    // TODO: If temporary this should be removed at the end.
+    // Full path of the temporary file containing the screenshot (when requested).
+    std::string screenshot_path_;
+
+    // TODO(b/111441001): remove when obsolete.
+    // Full path of the final zip file inside the caller-specified directory, if available.
+    std::string final_path_;
+
+    // The caller-specified directory, if available.
+    std::string bugreport_dir_;
+
     // Pointer to the zipped file.
     std::unique_ptr<FILE, int (*)(FILE*)> zip_file{nullptr, fclose};
 
diff --git a/cmds/dumpstate/utils.cpp b/cmds/dumpstate/utils.cpp
index 6cbb691676..d97ffbf2ed 100644
--- a/cmds/dumpstate/utils.cpp
+++ b/cmds/dumpstate/utils.cpp
@@ -229,7 +229,11 @@ bool Dumpstate::IsZipping() const {
 }
 
 std::string Dumpstate::GetPath(const std::string& suffix) const {
-    return android::base::StringPrintf("%s/%s-%s%s", bugreport_dir_.c_str(), base_name_.c_str(),
+    return GetPath(bugreport_internal_dir_, suffix);
+}
+
+std::string Dumpstate::GetPath(const std::string& directory, const std::string& suffix) const {
+    return android::base::StringPrintf("%s/%s-%s%s", directory.c_str(), base_name_.c_str(),
                                        name_.c_str(), suffix.c_str());
 }