AU: Execute postinst asynchronously so that the D-Bus service is not blocked.
This CL also cleans up Subprocess memory handling a bit and extends it to
capture the output of asynchronous subprocesses. Also adds a scoped temp mount
unmounter utility class.
BUG=8937
TEST=unit tests, tested on the device -- making sure no D-Bus calls timeou
during postinstall.
Change-Id: I219dda3dc98d875ff05050f1a32ffcc925db1d53
Review URL: http://codereview.chromium.org/4690006
diff --git a/subprocess.cc b/subprocess.cc
index af5fb75..9c19367 100755
--- a/subprocess.cc
+++ b/subprocess.cc
@@ -13,26 +13,55 @@
#include "base/string_util.h"
using std::string;
+using std::tr1::shared_ptr;
using std::vector;
namespace chromeos_update_engine {
void Subprocess::GChildExitedCallback(GPid pid, gint status, gpointer data) {
- COMPILE_ASSERT(sizeof(guint) == sizeof(uint32_t),
- guint_uint32_size_mismatch);
- guint* tag = reinterpret_cast<guint*>(data);
- const SubprocessCallbackRecord& record = Get().callback_records_[*tag];
- if (record.callback)
- record.callback(status, record.callback_data);
+ SubprocessRecord* record = reinterpret_cast<SubprocessRecord*>(data);
+
+ // Make sure we read any remaining process output. Then close the pipe.
+ GStdoutWatchCallback(record->gioout, G_IO_IN, &record->stdout);
+ int fd = g_io_channel_unix_get_fd(record->gioout);
+ g_source_remove(record->gioout_tag);
+ g_io_channel_unref(record->gioout);
+ close(fd);
+
g_spawn_close_pid(pid);
- Get().callback_records_.erase(*tag);
- delete tag;
+ if (status) {
+ LOG(INFO) << "Subprocess status: " << status;
+ }
+ if (!record->stdout.empty()) {
+ LOG(INFO) << "Subprocess output:\n" << record->stdout;
+ }
+ if (record->callback) {
+ record->callback(status, record->stdout, record->callback_data);
+ }
+ Get().subprocess_records_.erase(record->tag);
}
void Subprocess::GRedirectStderrToStdout(gpointer user_data) {
dup2(1, 2);
}
+gboolean Subprocess::GStdoutWatchCallback(GIOChannel* source,
+ GIOCondition condition,
+ gpointer data) {
+ string* stdout = reinterpret_cast<string*>(data);
+ char buf[1024];
+ gsize bytes_read;
+ while (g_io_channel_read_chars(source,
+ buf,
+ arraysize(buf),
+ &bytes_read,
+ NULL) == G_IO_STATUS_NORMAL &&
+ bytes_read > 0) {
+ stdout->append(buf, bytes_read);
+ }
+ return TRUE; // Keep the callback source. It's freed in GChilExitedCallback.
+}
+
namespace {
void FreeArgv(char** argv) {
for (int i = 0; argv[i]; i++) {
@@ -106,33 +135,47 @@
}
ScopedFreeArgPointer argp_free(argp);
- SubprocessCallbackRecord callback_record;
- callback_record.callback = callback;
- callback_record.callback_data = p;
-
- bool success = g_spawn_async(NULL, // working directory
- argv.get(),
- argp,
- G_SPAWN_DO_NOT_REAP_CHILD, // flags
- NULL, // child setup function
- NULL, // child setup data pointer
- &child_pid,
- &err);
+ shared_ptr<SubprocessRecord> record(new SubprocessRecord);
+ record->callback = callback;
+ record->callback_data = p;
+ gint stdout_fd = -1;
+ bool success = g_spawn_async_with_pipes(
+ NULL, // working directory
+ argv.get(),
+ argp,
+ G_SPAWN_DO_NOT_REAP_CHILD, // flags
+ GRedirectStderrToStdout, // child setup function
+ NULL, // child setup data pointer
+ &child_pid,
+ NULL,
+ &stdout_fd,
+ NULL,
+ &err);
FreeArgv(argv.get());
if (!success) {
LOG(ERROR) << "g_spawn_async failed";
return 0;
}
- guint* tag = new guint;
- *tag = g_child_watch_add(child_pid, GChildExitedCallback, tag);
- callback_records_[*tag] = callback_record;
- return *tag;
+ record->tag =
+ g_child_watch_add(child_pid, GChildExitedCallback, record.get());
+ subprocess_records_[record->tag] = record;
+
+ // Capture the subprocess output.
+ record->gioout = g_io_channel_unix_new(stdout_fd);
+ g_io_channel_set_encoding(record->gioout, NULL, NULL);
+ LOG_IF(WARNING,
+ g_io_channel_set_flags(record->gioout, G_IO_FLAG_NONBLOCK, NULL) !=
+ G_IO_STATUS_NORMAL) << "Unable to set non-blocking I/O mode.";
+ record->gioout_tag = g_io_add_watch(
+ record->gioout,
+ static_cast<GIOCondition>(G_IO_IN | G_IO_PRI | G_IO_ERR | G_IO_HUP),
+ GStdoutWatchCallback,
+ &record->stdout);
+ return record->tag;
}
void Subprocess::CancelExec(uint32_t tag) {
- if (callback_records_[tag].callback) {
- callback_records_[tag].callback = NULL;
- }
+ subprocess_records_[tag]->callback = NULL;
}
bool Subprocess::SynchronousExecFlags(const std::vector<std::string>& cmd,
@@ -178,6 +221,16 @@
return success;
}
+bool Subprocess::SubprocessInFlight() {
+ for (std::map<int, shared_ptr<SubprocessRecord> >::iterator it =
+ subprocess_records_.begin();
+ it != subprocess_records_.end(); ++it) {
+ if (it->second->callback)
+ return true;
+ }
+ return false;
+}
+
Subprocess* Subprocess::subprocess_singleton_ = NULL;
} // namespace chromeos_update_engine