jsonlogger: add test file and improve open/close behaviour

impl/src/jsonlogger.c

@@ -15,14 +15,36 @@
 	}
 
 static int m_fifo_fd = -1;
+static char m_fifo_path[1024];
 
 static bool start_message(void)
 {
+	if(m_fifo_fd < 0) {
+		// FIFO was not opened yet. Try to open it now.
+		m_fifo_fd = open(m_fifo_path, O_WRONLY | O_NONBLOCK);
+		if(m_fifo_fd < 0) {
+			if(errno != ENXIO) {
+				perror("open");
+			}
+			return false;
+		}
+	}
+
 	ssize_t ret = write(m_fifo_fd, "{", 1);
 	if(ret < 0) {
 		// FIFO is not writable or other error
-		if(errno != EAGAIN) {
+		switch(errno) {
+			case EAGAIN: // FIFO not ready for writing -> drop message
+				break;
+
+			case EPIPE: // FIFO was closed on the other side
+				close(m_fifo_fd);
+				m_fifo_fd = -1;
+				break;
+
+			default: // other errors are logged to stderr
 				perror("write");
+				break;
 		}
 
 		return false;
@@ -58,12 +80,9 @@ bool jsonlogger_init(const char *fifoname)
 		}
 	}
 
-	// FIFO was created or did already exist -> open it
-	m_fifo_fd = open(fifoname, O_WRONLY | O_NONBLOCK);
-	if(m_fifo_fd < 0) {
-		perror("open");
-		return false;
-	}
+	strncpy(m_fifo_path, fifoname, sizeof(m_fifo_path));
+
+	m_fifo_fd = -1; // open on demand
 
 	return true;
 }
@@ -108,7 +127,7 @@ bool jsonlogger_log_rx_stats(const rx_stats_t *rx_stats)
 	LOG_OR_RETURN("\"preambles_found\": %zd, ", rx_stats->preambles_found);
 	LOG_OR_RETURN("\"successful_decodes\": %zd, ", rx_stats->successful_decodes);
 	LOG_OR_RETURN("\"failed_decodes\": %zd, ", rx_stats->failed_decodes);
-	LOG_OR_RETURN("\"header_errors\": %zd, ", rx_stats->header_errors);
+	LOG_OR_RETURN("\"header_errors\": %zd", rx_stats->header_errors);
 
 	return end_message();
 }

impl/test/CMakeLists.txt

@@ -11,7 +11,7 @@ add_executable(
 target_link_libraries(
 	test_correlator
 	m
-	liquid
+	/usr/local/lib64/libliquid.a
 )
 
 #------------------------------------
@@ -46,7 +46,7 @@ add_executable(
 target_link_libraries(
 	test_layer1_loopback
 	m
-	liquid
+	/usr/local/lib64/libliquid.a
 	fftw3
 	fftw3f
 	fec
@@ -66,7 +66,7 @@ target_link_libraries(
 	test_freq_est
 	fftw3f
 	m
-	liquid
+	/usr/local/lib64/libliquid.a
 )
 
 #------------------------------------
@@ -98,5 +98,22 @@ target_link_libraries(
 	fec
 	fftw3f
 	m
-	liquid
+	/usr/local/lib64/libliquid.a
+)
+
+#------------------------------------
+
+add_executable(
+	test_jsonlogger
+	../src/jsonlogger.c
+	../src/jsonlogger.h
+	../src/debug_structs.h
+	test_jsonlogger.c
+)
+
+target_link_libraries(
+	test_freq_est
+	fftw3f
+	m
+	/usr/local/lib64/libliquid.a
 )

impl/test/test_jsonlogger.c

@@ -0,0 +1,72 @@
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include "../src/jsonlogger.h"
+#include "../src/debug_structs.h"
+
+static rx_stats_t m_rx_stats;
+
+static bool m_running;
+
+static void signal_handler(int signal, siginfo_t *info, void *ctx)
+{
+	(void)signal;
+	(void)info;
+	(void)ctx;
+
+	fprintf(stderr, "\nGracefully shutting down on signal %d.\n", signal);
+
+	m_running = false;
+}
+
+
+int main()
+{
+	if(!jsonlogger_init("jsonlog_test.fifo")) {
+		fprintf(stderr, "Could not initialize JSON logger.\n");
+		return EXIT_FAILURE;
+	}
+
+	// ** Set up signal handling
+
+	struct sigaction term_action = {0};
+	term_action.sa_sigaction = signal_handler;
+
+	if(sigaction(SIGTERM, &term_action, NULL) < 0) {
+		perror("sigaction");
+		exit(EXIT_FAILURE);
+	}
+
+	if(sigaction(SIGINT, &term_action, NULL) < 0) {
+		perror("sigaction");
+		exit(EXIT_FAILURE);
+	}
+
+	// ignore SIGPIPE
+	term_action.sa_sigaction = SIG_IGN;
+
+	if(sigaction(SIGPIPE, &term_action, NULL) < 0) {
+		perror("sigaction");
+		exit(EXIT_FAILURE);
+	}
+
+	m_running = true;
+	while(m_running) {
+		m_rx_stats.preambles_found++;
+		m_rx_stats.successful_decodes += 2;
+		m_rx_stats.failed_decodes += 3;
+		m_rx_stats.header_errors += 4;
+
+		jsonlogger_log_rx_stats(&m_rx_stats);
+
+		sleep(1);
+	}
+
+	// ** Cleanup **
+
+	jsonlogger_shutdown();
+
+	fprintf(stderr, "Done.\n");
+}