swaglog: Fix random test failure (commaai#23546)

* print info

* retry zmq_recv on errors

* get line no from __LINE__

* cleanup

* renmae msg to thread_id

selfdrive/common/tests/test_swaglog.cc

@@ -12,18 +12,20 @@
 const char *SWAGLOG_ADDR = "ipc:///tmp/logmessage";
 std::string daemon_name = "testy";
 std::string dongle_id = "test_dongle_id";
+int LINE_NO = 0;
 
-void log_thread(int msg, int msg_cnt) {
+void log_thread(int thread_id, int msg_cnt) {
   for (int i = 0; i < msg_cnt; ++i) {
-    LOGD("%d", msg);
+    LOGD("%d", thread_id);
+    LINE_NO = __LINE__ - 1;
     usleep(1);
   }
 }
 
 void send_stop_msg(void *zctx) {
   void *sock = zmq_socket(zctx, ZMQ_PUSH);
   zmq_connect(sock, SWAGLOG_ADDR);
-  zmq_send(sock, "", 0, ZMQ_NOBLOCK);
+  zmq_send(sock, "stop", 4, ZMQ_NOBLOCK);
   zmq_close(sock);
 }
 
@@ -34,7 +36,11 @@ void recv_log(void *zctx, int thread_cnt, int thread_msg_cnt) {
 
   while (true) {
     char buf[4096] = {};
-    if (zmq_recv(sock, buf, sizeof(buf), 0) == 0) break;
+    if (zmq_recv(sock, buf, sizeof(buf), 0) <= 0) {
+      if (errno == EAGAIN || errno == EINTR || errno == EFSM) continue;
+      break;
+    }
+    if (strcmp(buf, "stop") == 0) break;
 
     REQUIRE(buf[0] == CLOUDLOG_DEBUG);
     std::string err;
@@ -44,7 +50,7 @@ void recv_log(void *zctx, int thread_cnt, int thread_msg_cnt) {
     REQUIRE(msg["levelnum"].int_value() == CLOUDLOG_DEBUG);
     REQUIRE_THAT(msg["filename"].string_value(), Catch::Contains("test_swaglog.cc"));
     REQUIRE(msg["funcname"].string_value() == "log_thread");
-    REQUIRE(msg["lineno"].int_value() == 18);  // TODO: do this automatically
+    REQUIRE(msg["lineno"].int_value() == LINE_NO);
 
     auto ctx = msg["ctx"];
     REQUIRE(ctx["daemon"].string_value() == daemon_name);
@@ -64,6 +70,7 @@ void recv_log(void *zctx, int thread_cnt, int thread_msg_cnt) {
     thread_msgs[thread_id]++;
   }
   for (int i = 0; i < thread_cnt; ++i) {
+    INFO("thread :" << i);
     REQUIRE(thread_msgs[i] == thread_msg_cnt);
   }
   zmq_close(sock);
@@ -78,12 +85,13 @@ TEST_CASE("swaglog") {
 
   void *zctx = zmq_ctx_new();
   send_stop_msg(zctx);
+
   std::vector<std::thread> log_threads;
   for (int i = 0; i < thread_cnt; ++i) {
     log_threads.push_back(std::thread(log_thread, i, thread_msg_cnt));
   }
-
   for (auto &t : log_threads) t.join();
+
   recv_log(zctx, thread_cnt, thread_msg_cnt);
   zmq_ctx_destroy(zctx);
 }