1 files changed, 162 insertions, 0 deletions

diff --git a/srv/d.c b/srv/d.c
new file mode 100644
index 0000000..3c9e482
--- /dev/null
+++ b/srv/d.c
@@ -0,0 +1,162 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <errno.h>
+#include <time.h>
+#include <arpa/inet.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netinet/udp.h>
+#include <poll.h>
+#include <sys/types.h>
+#include <error.h>
+#include <endian.h>
+#include <inttypes.h>
+#include <signal.h>
+#include <netdb.h>
+#define S0(x) (x ? x : "")
+struct entry {
+	uint64_t time __attribute__((packed));
+	uint64_t value __attribute__((packed));
+} __attribute__((packed));
+int samomor = 0;
+void handle_me (int s __attribute__((unused))) {
+	samomor++;
+}
+int main (int argc, char ** argv) {
+	if (argc < 1+1)
+		error_at_line(1, 0, __FILE__, __LINE__, "uporaba: %s db [port=35358] [bind=::] [src=]", S0(argv[0]));
+	struct sigaction act = {
+		.sa_handler = handle_me,
+		.sa_flags = SA_RESTART
+	};
+	if (sigaction(SIGINT, &act, NULL) == -1)
+		error_at_line(2, errno, __FILE__, __LINE__, "sigaction SIGINT");
+	if (sigaction(SIGTERM, &act, NULL) == -1)
+		error_at_line(3, errno, __FILE__, __LINE__, "sigaction SIGTERM");
+#define DB argv[1]
+	int port = 35358;
+	if (argc >= 1+2)
+		port = atoi(argv[2]);
+	struct sockaddr_in6 bind_address = {
+		.sin6_family = AF_INET6,
+		.sin6_port = htons(port),
+		.sin6_addr = in6addr_any
+	};
+	if (argc >= 1+3)
+		switch (inet_pton(AF_INET6, argv[3], &bind_address.sin6_addr)) {
+			case 0:
+				error_at_line(4, 0, __FILE__, __LINE__, "!inet_pton(AF_INET6, argv[3], &bind_address.sin6_addr)");
+				break;
+			case -1:
+				error_at_line(5, errno, __FILE__, __LINE__, "inet_pton");
+		}
+	struct sockaddr_in6 src = {
+		.sin6_family = AF_INET6,
+		.sin6_port = htons(port),
+		.sin6_addr = in6addr_any
+	};
+	int whitelist_src = 0;
+	if (argc >= 1+4) {
+		whitelist_src++;
+		switch (inet_pton(AF_INET6, argv[4], &src.sin6_addr)) {
+			case 0:
+				error_at_line(6, 0, __FILE__, __LINE__, "!inet_pton(AF_INET6, argv[4], &src.sin6_addr)");
+				break;
+			case -1:
+				error_at_line(7, errno, __FILE__, __LINE__, "inet_pton");
+		}
+	}
+	int udp = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP);
+	if (udp == -1)
+		error_at_line(10, errno, __FILE__, __LINE__, "socket");
+	FILE * db = NULL;
+	int z = 1;
+	int r = 0;
+	if (setsockopt(udp, SOL_SOCKET, SO_BROADCAST, &z, sizeof z) == -1) {
+		error_at_line(0, errno, __FILE__, __LINE__, "setsockopt");
+		r = 11;
+		goto r;
+	}
+	if (bind(udp, (struct sockaddr *) &bind_address, sizeof bind_address)) {
+		error_at_line(0, errno, __FILE__, __LINE__, "bind");
+		r = 12;
+		goto r;
+	}
+	if (!(db = fopen(DB, "a"))) {
+		error_at_line(0, errno, __FILE__, __LINE__, "fopen");
+		r = 13;
+		goto r;
+	}
+	while (!samomor) {
+		struct pollfd pollfd = {
+			.fd = udp,
+			.events = POLLIN | POLLERR | POLLHUP | POLLNVAL
+		};
+		if (poll(&pollfd, 1, -1) == -1) {
+			error_at_line(0, errno, __FILE__, __LINE__, "poll");
+			r = 14;
+			goto r;
+		}
+		if ((pollfd.revents & POLLERR) || (pollfd.revents & POLLHUP) || (pollfd.revents & POLLNVAL)) {
+			error_at_line(0, 0, __FILE__, __LINE__, "POLLERR || POLLHUP || POLLNVAL");
+			r = 15;
+			goto r;
+		}
+		struct sockaddr_storage sender;
+		socklen_t sender_len = sizeof sender;
+		char buf[512];
+		ssize_t bytes = recvfrom(udp, buf, 256, MSG_DONTWAIT, (struct sockaddr *) &sender, &sender_len);
+		if (bytes == -1) {
+			error_at_line(0, errno, __FILE__, __LINE__, "recvfrom");
+			r = 16;
+			goto r;
+		}
+		struct timespec current_time;
+		if (clock_gettime(CLOCK_REALTIME, &current_time) == -1) {
+			error_at_line(0, errno, __FILE__, __LINE__, "clock_gettime");
+			r = 17;
+			goto r;
+		}
+		uint64_t current_time_us = current_time.tv_sec*1000000+current_time.tv_nsec/1000;
+		unsigned long long int current_Wh = strtoull(buf, NULL, 10);
+		struct entry entry = {
+			.time = htobe64(current_time_us),
+			.value = htobe64(current_Wh)
+		};
+		char sender_host[512];
+		char sender_port[512];
+		int gni = getnameinfo((struct sockaddr *) &sender, sender_len, sender_host, 512, sender_port, 512, NI_DGRAM | NI_NUMERICHOST | NI_NUMERICSERV);
+		if (gni) {
+			error_at_line(0, 0, __FILE__, __LINE__, "getnameinfo: %s", gai_strerror(gni));
+			r = 19;
+			goto r;
+		}
+		time_t sedaj = time(NULL);
+		strcpy(buf, ctime(&sedaj));
+		buf[strlen(buf)-1] = '\0';
+		if (sender.ss_family != AF_INET6)
+			if (whitelist_src) {
+				fprintf(stderr, "[%s] %s:%s\tsender.ss_family != AF_INET6\n", buf, sender_host, sender_port);
+				continue;
+			}
+		if (whitelist_src && memcmp(&((struct sockaddr_in6 *) &sender)->sin6_addr, &src.sin6_addr, sizeof(src.sin6_addr))) {
+			fprintf(stderr, "[%s] %s:%s\tfailed src whitelist\n", buf, sender_host, sender_port);
+			continue;
+		}
+		fprintf(stderr, "[%s] %s:%s\t%llu Wh\n", buf, sender_host, sender_port, current_Wh);
+		if (fwrite(&entry, sizeof entry, 1, db) != 1) {
+			error_at_line(0, 0, __FILE__, __LINE__, "fwrite");
+			r = 18;
+			goto r;
+		}
+	}
+r:
+	if (close(udp) == -1)
+		error_at_line(19, errno, __FILE__, __LINE__, "close(udp)");
+	if (db != NULL)
+		if (fclose(db) == -1)
+			error_at_line(20, errno, __FILE__, __LINE__, "fclose(db)");
+	return r;
+}