test: add unit tests for do_send seq lifecycle and error handling

tests/send/test_do_send.c

@@ -0,0 +1,106 @@
+#include <criterion/criterion.h>
+#include <netinet/in.h>
+#include "compiler.h"
+#include <stddef.h>
+#include <stdint.h>
+
+#include "icmp.h"
+#include "internal/ping/send.h"
+#include "internal/ping/ping_state.h"
+#include "internal/ping/tracker.h"
+#include "ping/ping.h"
+
+/* Controllable mock state */
+int g_mock_send_ret;
+int g_mock_retry_ret;
+
+int __wrap_icmp_send_echo(icmp_handle_t *h __unused, struct in_addr dest
+		__unused, uint16_t id __unused, uint16_t seq __unused, uint8_t ttl
+		__unused, const void *payload __unused, size_t len __unused)
+{
+	return g_mock_send_ret;
+}
+
+int __wrap_icmp_should_retry(const icmp_handle_t *h __unused)
+{
+	return g_mock_retry_ret;
+}
+
+const char *__wrap_icmp_strerror(const icmp_handle_t *h __unused)
+{
+	return "mock error";
+}
+
+int __wrap_ping_scheduler_arm(const struct ping_config *c __unused)
+{
+	return 0;
+}
+
+static struct ping_config	g_config;
+static struct ping_tracker	g_tracker;
+static struct ping_state	g_state;
+
+static void
+setup(void)
+{
+	g_config  = (struct ping_config){0};
+	g_state   = (struct ping_state){
+		.handle  = NULL,
+		.config  = &g_config,
+		.tracker = &g_tracker,
+		.seq     = 0,
+	};
+	ping_tracker_init(&g_tracker);
+	g_mock_send_ret  = 0;
+	g_mock_retry_ret = 0;
+}
+
+Test(do_send, success_increments_seq, .init = setup)
+{
+	g_mock_send_ret = 0;
+	do_send(&g_state, 16);
+	cr_assert_eq(g_state.seq, (uint16_t)1);
+	cr_assert_eq(g_tracker.nb_sent, (size_t)1);
+}
+
+Test(do_send, eagain_does_not_consume_seq, .init = setup)
+{
+	g_mock_send_ret  = 1;
+	g_mock_retry_ret = 1;
+	do_send(&g_state, 16);
+	cr_assert_eq(g_state.seq, (uint16_t)0);
+	cr_assert_eq(g_tracker.nb_sent, (size_t)0);
+}
+
+Test(do_send, hard_error_does_not_consume_seq, .init = setup)
+{
+	g_mock_send_ret  = -1;
+	g_mock_retry_ret = 0;
+	do_send(&g_state, 16);
+	cr_assert_eq(g_state.seq, (uint16_t)0);
+	cr_assert_eq(g_tracker.nb_sent, (size_t)0);
+}
+
+Test(do_send, multiple_success_increments_seq, .init = setup)
+{
+	g_mock_send_ret = 0;
+	do_send(&g_state, 16);
+	do_send(&g_state, 16);
+	do_send(&g_state, 16);
+	cr_assert_eq(g_state.seq, (uint16_t)3);
+	cr_assert_eq(g_tracker.nb_sent, (size_t)3);
+}
+
+Test(do_send, eagain_then_success_uses_same_seq, .init = setup)
+{
+	g_mock_send_ret  = 1;
+	g_mock_retry_ret = 1;
+	do_send(&g_state, 16);
+	cr_assert_eq(g_state.seq, (uint16_t)0);
+
+	g_mock_send_ret  = 0;
+	g_mock_retry_ret = 0;
+	do_send(&g_state, 16);
+	cr_assert_eq(g_state.seq, (uint16_t)1);
+	cr_assert_eq(g_tracker.nb_sent, (size_t)1);
+}