cleanup(modern_bpf): address review comments

Signed-off-by: Luca Guerra <luca@guerra.sh>
Co-authored-by: Andrea Terzolo <andreaterzolo3@gmail.com>

Author: 2 people

userspace/libpman/src/maps.c

@@ -115,64 +115,82 @@ int pman_update_capture_settings(struct capture_settings* settings) {
 
 void pman_set_snaplen(uint32_t desired_snaplen) {
 	struct capture_settings settings;
-	pman_get_capture_settings(&settings);
+	if(pman_get_capture_settings(&settings) != 0) {
+		return;
+	}
 	settings.snaplen = desired_snaplen;
 	pman_update_capture_settings(&settings);
 }
 
 void pman_set_boot_time(uint64_t boot_time) {
 	struct capture_settings settings;
-	pman_get_capture_settings(&settings);
+	if(pman_get_capture_settings(&settings) != 0) {
+		return;
+	}
 	settings.boot_time = boot_time;
 	pman_update_capture_settings(&settings);
 }
 
 void pman_set_dropping_mode(bool value) {
 	struct capture_settings settings;
-	pman_get_capture_settings(&settings);
+	if(pman_get_capture_settings(&settings) != 0) {
+		return;
+	}
 	settings.dropping_mode = value;
 	pman_update_capture_settings(&settings);
 }
 
 void pman_set_sampling_ratio(uint32_t value) {
 	struct capture_settings settings;
-	pman_get_capture_settings(&settings);
+	if(pman_get_capture_settings(&settings) != 0) {
+		return;
+	}
 	settings.sampling_ratio = value;
 	pman_update_capture_settings(&settings);
 }
 
 void pman_set_drop_failed(bool drop_failed) {
 	struct capture_settings settings;
-	pman_get_capture_settings(&settings);
+	if(pman_get_capture_settings(&settings) != 0) {
+		return;
+	}
 	settings.drop_failed = drop_failed;
 	pman_update_capture_settings(&settings);
 }
 
 void pman_set_do_dynamic_snaplen(bool do_dynamic_snaplen) {
 	struct capture_settings settings;
-	pman_get_capture_settings(&settings);
+	if(pman_get_capture_settings(&settings) != 0) {
+		return;
+	}
 	settings.do_dynamic_snaplen = do_dynamic_snaplen;
 	pman_update_capture_settings(&settings);
 }
 
 void pman_set_fullcapture_port_range(uint16_t range_start, uint16_t range_end) {
 	struct capture_settings settings;
-	pman_get_capture_settings(&settings);
+	if(pman_get_capture_settings(&settings) != 0) {
+		return;
+	}
 	settings.fullcapture_port_range_start = range_start;
 	settings.fullcapture_port_range_end = range_end;
 	pman_update_capture_settings(&settings);
 }
 
 void pman_set_statsd_port(uint16_t statsd_port) {
 	struct capture_settings settings;
-	pman_get_capture_settings(&settings);
+	if(pman_get_capture_settings(&settings) != 0) {
+		return;
+	}
 	settings.statsd_port = statsd_port;
 	pman_update_capture_settings(&settings);
 }
 
 void pman_set_scap_tid(int32_t scap_tid) {
 	struct capture_settings settings;
-	pman_get_capture_settings(&settings);
+	if(pman_get_capture_settings(&settings) != 0) {
+		return;
+	}
 	settings.scap_tid = scap_tid;
 	pman_update_capture_settings(&settings);
 }
@@ -198,28 +216,6 @@ void pman_fill_syscall_sampling_table() {
 	}
 }
 
-int pman_init_settings_map() {
-	char error_message[MAX_ERROR_MESSAGE_LEN];
-	struct capture_settings settings = {};
-	uint32_t key = 0;
-	int fd = bpf_map__fd(g_state.skel->maps.capture_settings);
-	if(fd <= 0) {
-		snprintf(error_message, MAX_ERROR_MESSAGE_LEN, "unable to get capture_settings map!");
-		pman_print_error((const char*)error_message);
-		return errno;
-	}
-
-	if(bpf_map_update_elem(fd, &key, &settings, BPF_ANY)) {
-		snprintf(error_message,
-		         MAX_ERROR_MESSAGE_LEN,
-		         "unable to initialize capture_settings map!");
-		pman_print_error((const char*)error_message);
-		return errno;
-	}
-
-	return 0;
-}
-
 void pman_fill_ia32_to_64_table() {
 	for(int syscall_id = 0; syscall_id < SYSCALL_TABLE_SIZE; syscall_id++) {
 		// Note: we will map all syscalls from the upper limit of the ia32 table
@@ -452,7 +448,8 @@ int pman_prepare_maps_before_loading() {
 
 int pman_finalize_maps_after_loading() {
 	int err;
-	err = pman_init_settings_map();
+	struct capture_settings settings = {};
+	err = pman_update_capture_settings(&settings);
 	if(err != 0) {
 		return err;
 	}