1 files changed, 58 insertions, 0 deletions
diff --git a/Semestr 4/sieci/pracownia3/utils.c b/Semestr 4/sieci/pracownia3/utils.c
new file mode 100644
index 0000000..4c2f449
--- /dev/null
+++ b/Semestr 4/sieci/pracownia3/utils.c
@@ -0,0 +1,58 @@
+/* Projekt: Transport
+ * Autor: Franciszek Malinka 316093
+ */
+
+#include "utils.h"
+#include <poll.h>
+#include <errno.h>
+#include <stdio.h>
+#include <netinet/ip.h>
+#include <arpa/inet.h>
+#include <stdlib.h>
+#include <string.h>
+
+size_t min(size_t x, size_t y) { return (x<y ? x : y); }
+
+int get_socket() {
+  int sockfd = socket(AF_INET, SOCK_DGRAM, 0);
+  if (sockfd < 0) {
+    fprintf(stderr, "socket error: %s", strerror(errno));
+    exit(EXIT_FAILURE);
+  }
+  return sockfd;
+}
+
+long get_time_interval(struct timespec start, struct timespec finish) {
+  return S_TO_MS(finish.tv_sec - start.tv_sec) + NS_TO_MS(finish.tv_nsec - start.tv_nsec);
+}
+
+int poll_socket_modify_timeout(int sockfd, int *timeout) {
+  if (*timeout < 0) {
+    *timeout = 0;
+    return 0;
+  }
+
+  struct pollfd fds;
+  struct timespec start;
+  struct timespec finish;
+  
+  fds.fd = sockfd;
+  fds.events = POLLIN;
+  fds.revents = 0;
+  
+  clock_gettime(CLOCK_REALTIME, &start);
+  int result = poll(&fds, 1, *timeout);
+  clock_gettime(CLOCK_REALTIME, &finish);
+  
+  if (result == -1) {
+    fprintf(stderr, "poll error: %s\n", strerror(errno));
+    exit(EXIT_FAILURE);
+  }
+  if (result == 0) {
+    *timeout = 0;
+    return 0;
+  }
+
+  *timeout -= get_time_interval(start, finish);
+  return result;
+}