From 5e56c37f2d93aca545f4a00a8c57d995d417fc4d Mon Sep 17 00:00:00 2001
From: ingenzi <vany.ingenzi@student.uclouvain.be>
Date: Thu, 17 Mar 2022 20:13:46 +0100
Subject: [PATCH] Advanced on the receiver
---
headers/receiver_utils.h | 16 +++++
src/our_utils.c | 2 +-
src/receiver.c | 17 ++----
src/receiver_utils.c | 128 +++++++++++++++++++++++++++++++++++++++
4 files changed, 149 insertions(+), 14 deletions(-)
create mode 100644 src/receiver_utils.c
diff --git a/headers/receiver_utils.h b/headers/receiver_utils.h
index a5cc853..572e45a 100644
--- a/headers/receiver_utils.h
+++ b/headers/receiver_utils.h
@@ -7,4 +7,20 @@
#ifndef __RECEIVER_UTILS_
#define __RECEIVER_UTILS_
+/* We are using 8 bits to encode the seqnum therefore to fight redondance our window is of 2**(8)/2 */
+#define MAX_SELECTIVE_REPEAT_WINDOW 8
+
+/* Represent the receiver's connection state */
+typedef struct __attribute__((__packed__))
+{
+} con_state_t;
+
+
+/**
+ * Loop reading on socket and printing to the stdout
+ * @sfd : The socket file descriptor. It is both bound and connected.
+ * @return: as soon as the whole transfer is done.
+ */
+void receiver_read_write_loop(int sfd);
+
#endif
\ No newline at end of file
diff --git a/src/our_utils.c b/src/our_utils.c
index b81e2f8..45e6305 100644
--- a/src/our_utils.c
+++ b/src/our_utils.c
@@ -78,7 +78,7 @@ int create_socket_connect(struct sockaddr_in6 * dest_addr)
int create_socket(struct sockaddr_in6 *source_addr, int src_port, struct sockaddr_in6 *dest_addr, int dst_port)
{
- if ( source_addr != NULL && dest_addr == NULL )
+ if ( source_addr != NULL && dest_addr == NULL )
{
source_addr->sin6_port = htons(src_port);
return create_socket_bind(source_addr);
diff --git a/src/receiver.c b/src/receiver.c
index dbb84be..9afa977 100644
--- a/src/receiver.c
+++ b/src/receiver.c
@@ -13,7 +13,7 @@
#include "log.h"
#include "packet_interface.h"
#include "our_utils.h"
-
+#include "receiver_utils.h"
int print_usage(char *prog_name) {
ERROR("Usage:\n\t%s [-s stats_filename] listen_ip listen_port", prog_name);
@@ -73,20 +73,11 @@ int main(int argc, char **argv) {
ERROR("An error occured when creating the socket\n");
return (EXIT_FAILURE);
}
- // 2. Wait for a client
- char * buff[PKT_MAX_LEN];
- ssize_t len;
- int err = wait_for_client(socket, PKT_MAX_LEN,(char *)buff, &len);
- if (err == 0)
- {
- close(socket);
- return (EXIT_FAILURE);
- }
-
- DEBUG_DUMP(buff, len);
- // 3. Start listening till end
+ ASSERT(stats_filename == NULL);
+ receiver_read_write_loop(socket);
close(socket);
+
return EXIT_SUCCESS;
}
\ No newline at end of file
diff --git a/src/receiver_utils.c b/src/receiver_utils.c
new file mode 100644
index 0000000..9722c55
--- /dev/null
+++ b/src/receiver_utils.c
@@ -0,0 +1,128 @@
+
+#include "log.h"
+#include "packet_interface.h"
+#include <poll.h>
+#include "our_utils.h"
+#include "receiver_utils.h"
+
+int send_data_if_inneed()
+{
+ return 1;
+}
+
+int handle_incoming_data()
+{
+ /*
+ char * buff;
+ ssize_t read_bytes = read(pfd->fd, (void *) buff, MAX_SIZE);
+ if (read_bytes == -1)
+ return 0;
+ err = fwrite((void *) buff, sizeof(char), read_bytes, stdout);
+ if (err == 0)
+ return 0;
+ err = fflush(stdout);
+ */
+ return 1;
+}
+
+int handle_revents(struct pollfd * pfd)
+{
+ DEBUG(" events: %s%s%s%s",
+ (pfd->revents & POLLIN) ? "POLLIN " : "",
+ (pfd->revents & POLLOUT) ? "POLLOUT " : "",
+ (pfd->revents & POLLHUP) ? "POLLHUP " : "",
+ (pfd->revents & POLLERR) ? "POLLERR " : "");
+
+ if (pfd->revents & POLLIN) /* POLLIN : There's data to read */
+ {
+ return handle_incoming_data();
+ } else if (pfd->revents & POLLHUP) /* POLLHUP : The other user disconnected from their side */
+ {
+ DEBUG("The sender disconnected.");
+ return 0;
+ } else if (pfd->revents & POLLOUT) /* POLLOUT : Possible to send that */
+ {
+ return send_data_if_inneed();
+ } else { /* POLLERR : An error occurred */
+ ERROR("Poll revents marks error.");
+ return 0;
+ }
+ return 1;
+}
+
+void reception_loop(struct pollfd * pfd, con_state_t * state, pkt_t * pkt)
+{
+ ASSERT(state != NULL || pkt != NULL);
+ int not_eof = 1;
+ while (not_eof)
+ {
+ int ready = poll(pfd, 1, -1);
+ if (ready == -1)
+ return;
+
+ if (pfd->revents != 0)
+ not_eof = handle_revents(pfd);
+ }
+}
+
+/**
+ * Waits for a client to send data to the socket and then connectes to the client
+ * @return: 0 upon success, -1 in case of an error. a message will be displayed to the stderr
+ */
+int connect_to_a_client(int sfd, pkt_t * init_pkt)
+{
+ char * buffer[PKT_MAX_LEN];
+ ssize_t written_in_buffer;
+ // We suppose that the first contact is going to be our client no need to check for more
+ int err = wait_for_client(sfd, PKT_MAX_LEN, (char *)buffer, &written_in_buffer);
+ if (err != 0) return -1;
+
+ DEBUG_DUMP(buffer, written_in_buffer);
+ pkt_status_code status = pkt_decode((char *) buffer, (size_t) written_in_buffer, init_pkt);
+ if (status != PKT_OK)
+ {
+ ERROR("When encoding the init_packet got pkt_status = %d", status);
+ return -1;
+ }
+ return 0;
+}
+
+/**
+ * This main loop for the receiver.
+ * @sfd: A valid socket.
+ * @return: As soon as an error occurs or, a the total transfer came through.
+ */
+void receiver_read_write_loop(int sfd)
+{
+ pkt_t * pkt = pkt_new();
+ con_state_t * state = malloc(sizeof(con_state_t));
+ struct pollfd * pfd = (struct pollfd *) calloc(1, sizeof(struct pollfd));
+ if (pkt == NULL || state == NULL || pfd == NULL) return;
+
+ pfd->fd = sfd;
+ pfd->events = POLLIN | POLLOUT;
+
+ int err = connect_to_a_client(sfd, pkt);
+ if (err == 0)
+ return;
+ // Handle initial packet.
+
+ err = fwrite((void *) pkt_get_payload(pkt), sizeof(char), pkt_get_length(pkt), stdout);
+ err = fflush(stdout);
+
+ /*
+ if (err == 0)
+ reception_loop(pfd, state, pkt);
+ */
+
+ char * buffer[PKT_MAX_LEN];
+ size_t len = PKT_MAX_LEN;
+
+ err = pkt_encode(pkt, (char *) buffer, &len);
+ if (err == 0)
+ err = write(pfd->fd, (void *) buffer, len);
+
+ pkt_del(pkt);
+ free(state);
+ free(pfd);
+}
\ No newline at end of file
--
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