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Diffstat (limited to 'client.c')
-rw-r--r--client.c195
1 files changed, 119 insertions, 76 deletions
diff --git a/client.c b/client.c
index 4c3573c..f9617cd 100644
--- a/client.c
+++ b/client.c
@@ -9,13 +9,9 @@
#include <sys/socket.h>
#include <ctype.h>
#include <pthread.h>
-
#include <arpa/inet.h>
-
#include "protocol.c"
-#define MAXDATASIZE 100 // max number of bytes we can get at once
-
#define MAX_READ_SIZE 1024
#define LINE_MAX 1024
@@ -43,9 +39,9 @@ int main(int argc, char *argv[])
int sockfd, numbytesrecv, numbytessent, recvbytes;
// char buf[MAXDATASIZE];
struct addrinfo hints, *servinfo, *p;
- int rv;
char s[INET6_ADDRSTRLEN];
+ // check arugments
if (argc != 4) {
fprintf(stderr,"<server IP> <server port> <listener port>\n");
exit(1);
@@ -58,11 +54,13 @@ int main(int argc, char *argv[])
char* tcpPort = argv[2]; // port we use to connect to server's tcp stream
char* udpPort = argv[3]; // port we use to connect to server's udp info and command
- if ((rv = getaddrinfo(argv[1], tcpPort, &hints, &servinfo)) != 0) {
+ // resolve host
+ int rv;
+ if ((rv = getaddrinfo(argv[1], tcpPort, &hints, &servinfo)) != 0)
+ {
fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(rv));
return 1;
}
-
// loop through all the results and connect to the first we can
for(p = servinfo; p != NULL; p = p->ai_next) {
if ((sockfd = socket(p->ai_family, p->ai_socktype,
@@ -76,34 +74,31 @@ int main(int argc, char *argv[])
perror("client: connect");
continue;
}
-
break;
}
-
if (p == NULL) {
fprintf(stderr, "client: failed to connect\n");
return 2;
}
-
- inet_ntop(p->ai_family, get_in_addr((struct sockaddr *)p->ai_addr),
- s, sizeof s);
- // printf("client: connecting to %s\n", s);
-
+ inet_ntop(p->ai_family, get_in_addr((struct sockaddr *)p->ai_addr), s, sizeof s);
freeaddrinfo(servinfo); // all done with this structure
+ // now that we're connectioned, let's do the handshake
uint16_t num_stations = handle_handshake(sockfd, udpPort);
+ // handle_handshake will end the program on fail
+ // so if we're here, num_stations is correct
fflush(stdout);
printf("Welcome to Snowcast! The server has %u stations.\n", num_stations);
fflush(stdout);
+ // start the thread to accept command lines
pthread_t command_line_thread;
pthread_create(&command_line_thread, NULL, command_line_routine, (void*)sockfd);
- // CONSIDER: could recieve the welcome message here
- // int recvbytes;
+ // this while loop hangs on recv and runs when there is new data
while (1) {
- // recv the first byte of the message to get it's type
+ // get the type of the incoming reply
uint8_t reply_type = -1;
// print size of utin8
if (recv(sockfd, &reply_type, 1, 0) == -1) {
@@ -114,35 +109,38 @@ int main(int argc, char *argv[])
exit(1);
}
- if (reply_type == 2) { // we have a second welcome message
+ if (reply_type == WELCOME) {
fprintf(stderr, "WECLOME reply received twice. Exiting.\n");
close(sockfd);
exit(1);
}
- if (reply_type == 3) { // we have an announce message
-
+ if (reply_type == ANNOUNCE) {
if (!station_is_set) {
fprintf(stderr, "ANNOUNCE reply received before SETSTATION command. Exiting.\n");
close(sockfd);
exit(1);
}
- // get the string size
+ // get the string size for the songname
u_int8_t string_size = -1;
if (recv(sockfd, &string_size, 1, 0) == -1) {
perror("recv in announce");
exit(1);
}
+
+ // read the songname
char *song_name = malloc(string_size);
if(song_name == NULL) { perror("malloc in song name"); }
-
int bytes_to_read = string_size;
if (recv_all(sockfd, song_name, &bytes_to_read) == -1) {
perror("recv_all in announce");
exit(1);
}
+ remove_timeout(sockfd); // have received all, so can remove timeout
+ if (l) printf("received ANNOUNCE reply.\n");
+ // print the songname
if (!waiting) printf("\n"); // note: this is worth the lines for a clean cmd prompt
waiting = 0;
fflush(stdout);
@@ -151,7 +149,9 @@ int main(int argc, char *argv[])
fflush(stdout);
free(song_name);
continue;
- } else if (reply_type == 4) { // we have an invalid command message
+ }
+
+ if (reply_type == INVALID) { // we have an invalid command message
// get the string size
u_int8_t string_size = -1;
if (recv(sockfd, &string_size, 1, 0) == -1) {
@@ -170,10 +170,15 @@ int main(int argc, char *argv[])
fflush(stdout);
free(message);
close(sockfd);
+
+ // close the program on all INVALID COMMANDS
exit(1);
}
- else if (reply_type == 6) { // we are getting STATIONINFO
- // get the string size
+
+ if (reply_type == STATIONINFO) { // we are getting STATIONINFO
+ if (l) printf("received STATIONINFO reply.\n");
+
+ // get the string size, which can be farily long (uint32_t)
uint32_t buf_string_size = -1;
int bytes_to_read = sizeof(uint32_t);
if (recv_all(sockfd, &buf_string_size, &bytes_to_read) == -1) {
@@ -182,7 +187,8 @@ int main(int argc, char *argv[])
}
uint32_t string_size = ntohl(buf_string_size);
- printf("string size: %d\n", string_size);
+
+ // recieve the message
char *info = malloc(string_size);
if(info == NULL) { perror("malloc in info"); }
bytes_to_read = string_size;
@@ -190,9 +196,9 @@ int main(int argc, char *argv[])
perror("recv_all 2 in stationinfo");
exit(1);
}
- remove_timeout(sockfd);
- if (l) printf("received STATIONINFO reply.\n");
+ remove_timeout(sockfd); // remove the timeout, now that we have the data
+ // print the info
fflush(stdout);
printf("Station Information:\n%s\n", info);
printf("snowcast_control> ");
@@ -201,32 +207,43 @@ int main(int argc, char *argv[])
free(info);
continue;
}
- else if (reply_type == 7) { // we are getting StationShutdown
+
+ if (reply_type == STATIONSHUTDOWN) { // we are getting StationShutdown
if (l) printf("received STATIONSHUTDOWN reply.\n");
- if (!waiting) printf("\n"); // note: this is worth the lines for a clean cmd prompt
+
+ if (!waiting) printf("\n"); // note: this is worth the lines for a clean cmd prompt :)
waiting = 0;
- remove_timeout(sockfd);
+
+ // station no longer set
+ station_is_set = 0;
fflush(stdout);
printf("This station has shut down. Please select a different station.\n");
printf("snowcast_control> ");
fflush(stdout);
continue;
}
- else if (reply_type == 8) { // we are getting NewStation
+
+ if (reply_type == NEWSTATION) { // we are getting NewStation
+ if (l) printf("received NEWSTATION reply.\n");
+
+ // get station number
uint16_t station_number = -1;
if (recv(sockfd, &station_number, 2, 0) == -1) {
perror("recv in new station");
exit(1);
}
station_number = ntohs(station_number);
- if (l) printf("received NEWSTATION reply.\n");
+
+ // print
fflush(stdout);
- printf("\nThere is now a new station @ index %d.\n", station_number);
+ printf("\nThere is now a new station @ index %u.\n", station_number);
printf("snowcast_control> ");
fflush(stdout);
+
continue;
}
+ // if we're here, lost conneciton to the server -> end the program
printf("\nsocket to server HUNGUP. Exiting.\n");
close(sockfd);
exit(1);
@@ -235,105 +252,131 @@ int main(int argc, char *argv[])
}
void *command_line_routine(void* args) {
+ // unpack sockfd as arg
int sockfd = (int) args;
+ // buffer for input
char input[LINE_MAX];
printf("Enter a number to change to it's station. Enter q to end stream.\n");
printf("snowcast_control> ");
fflush(stdout);
while (1) {
+ memset(input, 0, LINE_MAX);
char *line = fgets(input, LINE_MAX, stdin);
+ // nothing was typed
if (line == NULL) {
continue;
- } else if (strncmp("q\n", input, LINE_MAX) == 0) {
+ }
+
+ // q command: exit the program
+ if (strncmp("q\n", input, LINE_MAX) == 0) {
// end code if type in q
exiting = 1;
printf("Exiting.\n");
close(sockfd);
exit(0);
- } else if (strncmp("l\n", input, LINE_MAX) == 0) {
+ }
+
+ // l command: STATIONINFO command (EXTRA CREDIT)
+ if (strncmp("l\n", input, LINE_MAX) == 0) {
// send the command to list stations
if (l) printf("sending LISTSTATIONS command. waiting for STATIONINFO reply.\n");
- apply_timeout(sockfd);
+ apply_timeout(sockfd); // apply a timeout, will be released when we get the reply
int list_station_reply_type = 5;
if (send(sockfd, &list_station_reply_type, 1, 0) == -1) {
perror("send");
exit(1);
}
- } else if (strncmp("log\n", input, LINE_MAX) == 0) {
+ continue;
+ }
+
+ // log command: toggle logging
+ if (strncmp("log\n", input, LINE_MAX) == 0)
+ {
l = !l;
printf("LOGGING is now %s!\n", l ? "on" : "off");
printf("snowcast_control> ");
fflush(stdout);
+ continue;
}
- else {
- // convert input to an int
- int inputInt = atoi(input);
- if (input[0] != '0' && inputInt == 0) {
- printf("unknown command: %si", input);
- printf("snowcast_control> ");
- fflush(stdout);
- continue;
- }
- // printf("Changing to station %d.\n", inputInt);
-
- // set waiting so no new line on announce
- waiting = 1;
- // send the command to change the station
- apply_timeout(sockfd);
- struct SetStation setStation;
- setStation.commandType = 1;
- setStation.stationNumber = htons(inputInt);
- int bytes_to_send = sizeof(struct SetStation);
- // apply_timeout(sockfd);
- if (send_all(sockfd, &setStation, &bytes_to_send) == -1) {
- perror("send_all");
- exit(1);
- }
- if (!station_is_set) {
- station_is_set = 1;
- }
+
+ // check if this could be a station number
+ int inputInt = atoi(input);
+ if (input[0] != '0' && inputInt == 0) {
+ // if we're in here, it's ~likely~ not a number (ik it's not perfect, sorry :/)
+ printf("unknown command: %si", input);
+ printf("snowcast_control> ");
+ fflush(stdout);
+ continue;
}
+
+ // if we're here, it was a valid number,
+ // & we need to send SETSTATION command.
+ if (l) printf("sending SETSTATION command.\n");
+ waiting = 1; // just for clean cmd
+
+ // setup struct
+ struct SetStation setStation;
+ setStation.commandType = SETSTATION;
+ setStation.stationNumber = htons(inputInt);
+ // send it
+ apply_timeout(sockfd); // apply timeout, will be released when we get ANNOUNCE reply
+ int bytes_to_send = sizeof(struct SetStation);
+ if (send_all(sockfd, &setStation, &bytes_to_send) == -1) {
+ perror("send_all");
+ exit(1);
+ }
+
+ if (!station_is_set) station_is_set = 1; // update, if needed
+ if (l) printf("waiting for ANNOUNCE reply...\n");
}
return (NULL);
}
uint16_t handle_handshake(int sockfd, char* udp_port) {
- apply_timeout(sockfd); // apply timeout for handshake
+ if (l) printf("found server, sending HELLO command.\n");
- if (l) printf("found server, sending HELLO command. waiting for ANNOUNCE reply.\n");
+ apply_timeout(sockfd); // apply timeout for handshake
+ // after we find connection, we need to send HELLO command
struct Hello hello;
- hello.commandType = 0;
+ hello.commandType = HELLO;
// convert updPort to an int
int udp_port_int = atoi(udp_port);
hello.udpPort = htons(udp_port_int);
- if (send(sockfd, &hello, sizeof(struct Hello), 0) == -1) {
+ int hello_len = sizeof(struct Hello);
+ if (send_all(sockfd, &hello, &hello_len) == -1) {
perror("send");
exit(1);
}
- // recv the first byte of the message to get it's type
+ if (l) printf("waiting for WELCOME reply...\n");
+
+ // read WELCOME reply type
uint8_t reply_type = -1;
// print size of utin8
- if (recv(sockfd, &reply_type, 1, 0) == -1) {
+ if (recv(sockfd, &reply_type, 1, 0) == -1) { // only one byte, so can use recv
perror("recv in handshake");
exit(1);
}
- // recv the message, check for errors too
+ if (reply_type != WELCOME) {
+ fprintf(stderr, "first reply is not WELCOME. Exiting.\n");
+ close(sockfd);
+ exit(1);
+ }
+
+ // get the number of stations
int16_t num_stations = -1;
int bytes_to_read = sizeof(uint16_t);
if (recv_all(sockfd, &num_stations, &bytes_to_read) == -1) {
perror("recv_all in handshake");
exit(1);
}
-
if (l) printf("received ANNOUNCE reply.\n");
- // remove timeout since we no longer are "waiting" for an immediate reply
- remove_timeout(sockfd);
- return ntohs(num_stations);
+ remove_timeout(sockfd); // remove timeout since we no longer are "waiting" for an immediate reply
+ return ntohs(num_stations); // return the num_stations to be printed
} \ No newline at end of file
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