Rewrite logcatd in Python (#36111)

* Add Python logcatd implementation

* lil more

SConstruct

@@ -338,10 +338,6 @@ SConscript([
   'system/ubloxd/SConscript',
   'system/loggerd/SConscript',
 ])
-if arch != "Darwin":
-  SConscript([
-    'system/logcatd/SConscript',
-  ])
 
 if arch == "larch64":
   SConscript(['system/camerad/SConscript'])

selfdrive/test/test_onroad.py

@@ -59,7 +59,7 @@ PROCS = {
   "system.proclogd": 3.0,
   "system.logmessaged": 1.0,
   "system.tombstoned": 0,
-  "./logcatd": 1.0,
+  "system.journald": 1.0,
   "system.micd": 5.0,
   "system.timed": 0,
   "selfdrive.pandad.pandad": 0,

system/journald.py

@@ -0,0 +1,43 @@
+#!/usr/bin/env python3
+import json
+import subprocess
+
+import cereal.messaging as messaging
+from openpilot.common.swaglog import cloudlog
+
+
+def main():
+  pm = messaging.PubMaster(['androidLog'])
+  cmd = ['journalctl', '-f', '-o', 'json']
+  proc = subprocess.Popen(cmd, stdout=subprocess.PIPE, text=True)
+  assert proc.stdout is not None
+  try:
+    for line in proc.stdout:
+      line = line.strip()
+      if not line:
+        continue
+      try:
+        kv = json.loads(line)
+      except json.JSONDecodeError:
+        cloudlog.exception("failed to parse journalctl output")
+        continue
+
+      msg = messaging.new_message('androidLog')
+      entry = msg.androidLog
+      entry.ts = int(kv.get('__REALTIME_TIMESTAMP', 0))
+      entry.message = json.dumps(kv)
+      if '_PID' in kv:
+        entry.pid = int(kv['_PID'])
+      if 'PRIORITY' in kv:
+        entry.priority = int(kv['PRIORITY'])
+      if 'SYSLOG_IDENTIFIER' in kv:
+        entry.tag = kv['SYSLOG_IDENTIFIER']
+
+      pm.send('androidLog', msg)
+  finally:
+    proc.terminate()
+    proc.wait()
+
+
+if __name__ == '__main__':
+  main()

system/logcatd/.gitignore

@@ -1 +0,0 @@
-logcatd

system/logcatd/SConscript

@@ -1,3 +0,0 @@
-Import('env', 'messaging', 'common')
-
-env.Program('logcatd', 'logcatd_systemd.cc', LIBS=[messaging, common, 'systemd'])

system/logcatd/logcatd_systemd.cc

@@ -1,75 +0,0 @@
-#include <systemd/sd-journal.h>
-
-#include <cassert>
-#include <csignal>
-#include <map>
-#include <string>
-
-#include "third_party/json11/json11.hpp"
-
-#include "cereal/messaging/messaging.h"
-#include "common/timing.h"
-#include "common/util.h"
-
-ExitHandler do_exit;
-int main(int argc, char *argv[]) {
-
-  PubMaster pm({"androidLog"});
-
-  sd_journal *journal;
-  int err = sd_journal_open(&journal, 0);
-  assert(err >= 0);
-  err = sd_journal_get_fd(journal); // needed so sd_journal_wait() works properly if files rotate
-  assert(err >= 0);
-  err = sd_journal_seek_tail(journal);
-  assert(err >= 0);
-
-  // workaround for bug https://github.com/systemd/systemd/issues/9934
-  // call sd_journal_previous_skip after sd_journal_seek_tail (like journalctl -f does) to makes things work.
-  sd_journal_previous_skip(journal, 1);
-
-  while (!do_exit) {
-    err = sd_journal_next(journal);
-    assert(err >= 0);
-
-    // Wait for new message if we didn't receive anything
-    if (err == 0) {
-      err = sd_journal_wait(journal, 1000 * 1000);
-      assert(err >= 0);
-      continue; // Try again
-    }
-
-    uint64_t timestamp = 0;
-    err = sd_journal_get_realtime_usec(journal, &timestamp);
-    assert(err >= 0);
-
-    const void *data;
-    size_t length;
-    std::map<std::string, std::string> kv;
-
-    SD_JOURNAL_FOREACH_DATA(journal, data, length) {
-      std::string str((char*)data, length);
-
-      // Split "KEY=VALUE"" on "=" and put in map
-      std::size_t found = str.find("=");
-      if (found != std::string::npos) {
-        kv[str.substr(0, found)] = str.substr(found + 1, std::string::npos);
-      }
-    }
-
-    MessageBuilder msg;
-
-    // Build message
-    auto androidEntry = msg.initEvent().initAndroidLog();
-    androidEntry.setTs(timestamp);
-    androidEntry.setMessage(json11::Json(kv).dump());
-    if (kv.count("_PID")) androidEntry.setPid(std::atoi(kv["_PID"].c_str()));
-    if (kv.count("PRIORITY")) androidEntry.setPriority(std::atoi(kv["PRIORITY"].c_str()));
-    if (kv.count("SYSLOG_IDENTIFIER")) androidEntry.setTag(kv["SYSLOG_IDENTIFIER"]);
-
-    pm.send("androidLog", msg);
-  }
-
-  sd_journal_close(journal);
-  return 0;
-}

system/manager/process_config.py

@@ -71,8 +71,8 @@ procs = [
 
   NativeProcess("camerad", "system/camerad", ["./camerad"], driverview, enabled=not WEBCAM),
   PythonProcess("webcamerad", "tools.webcam.camerad", driverview, enabled=WEBCAM),
-  NativeProcess("logcatd", "system/logcatd", ["./logcatd"], only_onroad, platform.system() != "Darwin"),
   PythonProcess("proclogd", "system.proclogd", only_onroad, enabled=platform.system() != "Darwin"),
+  PythonProcess("journald", "system.journald", only_onroad, platform.system() != "Darwin"),
   PythonProcess("micd", "system.micd", iscar),
   PythonProcess("timed", "system.timed", always_run, enabled=not PC),