Client can now actually send messages via command

Client can now specify the recipient of a message and type it. Messages for offline users are saved, unaccesible for now.

Makefile

@@ -5,11 +5,11 @@ all: client server
 
 client:
 	mkdir -p build
-	$(CC) $(CFLAGS) -o build/client client.c
+	$(CC) $(CFLAGS) -o build/client client.c util/util.c
 
 server:
 	mkdir -p build
-	$(CC) $(CFLAGS) -o build/server server.c
+	$(CC) $(CFLAGS) -o build/server server.c util/util.c
 
 clean:
 	rm -f client server

client.c

@@ -29,6 +29,70 @@ static void cleanup_queue(int qid) {
   }
 }
 
+static void input_loop(int server_queue_id, const char *client_id) {
+  while (1) {
+    // Minimum length plus extra space fore command name and seperators
+    // I'd prefer some more space than required to not have to worry about cut
+    // offs
+    char buffer[COMMAND_LENGTH + MESSAGE_LENGTH + 64];
+    if (fgets(buffer, sizeof(buffer), stdin) == NULL) {
+      break;
+    }
+
+    buffer[strcspn(buffer, "\n")] = '\0';
+
+    if (strncmp(buffer, "/msg ", 5) == 0) {
+      // In a /msg command we expect {u|g}:<nickname up to 14 chars> <message up
+      // to 256 chars>
+      char *space_ptr = strchr(buffer + 5, ' ');
+      if (space_ptr == NULL) {
+        printf("Invalid /msg format. Use /msg u:<nickname> <message>\n");
+        continue;
+      }
+      char target[COMMAND_LENGTH];
+      size_t target_len = space_ptr - (buffer + 5);
+      if (target_len >= COMMAND_LENGTH) {
+        printf("Target nickname too long\n");
+        continue;
+      }
+      strncpy(target, buffer + 5, target_len);
+      target[target_len] = '\0';
+      char *message = space_ptr + 1;
+      if (strlen(message) == 0) {
+        printf("Message cannot be empty\n");
+        continue;
+      }
+
+      // Check the format of the command string
+      if (target[1] != ':') {
+        printf("Invalid target format. Use u:<nickname> or g:<groupname>\n");
+        continue;
+      }
+
+      if (target[0] != 'u' && target[0] != 'g') {
+        printf("Invalid target type. Use 'u' for user or 'g' for group\n");
+        continue;
+      }
+
+      msgbuf_t msg = {.mtype = Message, .sender = ""};
+      strncpy(msg.sender, client_id, COMMAND_LENGTH - 1);
+      snprintf(msg.command, COMMAND_LENGTH, "%s", target);
+      strncpy(msg.message, message, MESSAGE_LENGTH - 1);
+      if (send(server_queue_id, &msg) == -1) {
+        perror("msgsnd(/msg) failed");
+      }
+    } else if (strncmp(buffer, "/list", 5) == 0) {
+      // handle list
+    } else if (strncmp(buffer, "/mute ", 6) == 0) {
+      // handle mute
+    } else if (strcmp(buffer, "/quit") == 0) {
+      // exit
+    } else {
+      printf("Unknown command\n");
+    }
+  }
+}
+
 int main(int argc, char *argv[]) {
   if (argc < 2) {
     fprintf(stderr, "Usage: %s <client_id>\n", argv[0]);
@@ -91,33 +155,27 @@ int main(int argc, char *argv[]) {
     return 0;
   }
 
-  /* Send a test message to the server */
+  if (fork() == 0) {
-  msgbuf_t test = {.mtype = Message, .sender = ""};
+    input_loop(server_queue_id, client_id);
-  strncpy(test.sender, client_id, COMMAND_LENGTH - 1);
+    return 0;
-  snprintf(test.message, MESSAGE_LENGTH, "Hello from %s", client_id);
-
-  if (msgsnd(server_queue_id, &test, sizeof(test) - sizeof(long), 0) == -1) {
-    printf("DEBUG: test.mtype = %u\n", test.mtype);
-    perror("failed while sending a test message");
-    cleanup_queue(client_queue_id);
-    return 1;
   }
 
-  printf("Sent test message to server: \"%s\"\n", test.message);
+  // /* Send a test message to the server */
+  // msgbuf_t test = {.mtype = Message, .command = "u:test2", .sender = ""};
+  // strncpy(test.sender, client_id, COMMAND_LENGTH - 1);
+  // snprintf(test.message, MESSAGE_LENGTH, "Hello from %s", client_id);
 
-  /* Now wait for server forwarded message(s) and a signal ack.
+  // if (msgsnd(server_queue_id, &test, sizeof(test) - sizeof(long), 0) == -1) {
-     We'll wait until we've seen both a Message and a Signal ack or timeout.
+  //   printf("DEBUG: test.mtype = %u\n", test.mtype);
-   */
+  //   perror("failed while sending a test message");
-  int seen_message = 0;
+  //   cleanup_queue(client_queue_id);
-  int seen_ack = 0;
+  //   return 1;
-  const int MAX_ITER = 10;
+  // }
 
-  // for (int i = 0; i < MAX_ITER && !(seen_message && seen_ack); ++i) {
   while (1) {
     msgbuf_t incoming;
     ssize_t got = msgrcv(client_queue_id, &incoming,
                          sizeof(incoming) - sizeof(long), 0, 0);
-    perror("Got a message damn");
     if (got == -1) {
       perror("msgrcv(incoming) failed");
 
@@ -130,14 +188,10 @@ int main(int argc, char *argv[]) {
 
     switch (incoming.mtype) {
     case Message:
-      printf("Received Message: \"%s\"\n", incoming.message);
+      printf("%s: %s\n", incoming.sender, incoming.message);
-      seen_message = 1;
       break;
     case Signal:
-      printf("Received Signal: code=%d\n", incoming.stype);
+
-      if (incoming.stype == ACK_ACCEPTED || incoming.stype == ACK_DELIVERED) {
-        seen_ack = 1;
-      }
       break;
     default:
       printf("Received unknown mtype=%ld stype=%d\n", (long)incoming.mtype,
@@ -146,15 +200,6 @@ int main(int argc, char *argv[]) {
     }
   }
 
-  if (!seen_message) {
-    fprintf(stderr, "Did not receive forwarded message from server\n");
-  }
-  if (!seen_ack) {
-    fprintf(stderr, "Did not receive ack from server\n");
-  }
-
-  /* Logout/cleanup: remove our queue */
   cleanup_queue(client_queue_id);
-  printf("Client exiting\n");
   return 0;
 }

server.c

@@ -13,10 +13,18 @@
 #include <unistd.h>
 
 #include "commands.h"
+#include "util/util.h"
 
 #define send(queue_id, msgbuf_ptr)                                             \
   msgsnd(queue_id, msgbuf_ptr, sizeof(*(msgbuf_ptr)) - sizeof(long), 0)
 
+typedef struct {
+  char sender[COMMAND_LENGTH];
+  char command[COMMAND_LENGTH];
+  char message[MESSAGE_LENGTH];
+  int message_id;
+} saved_message_t;
+
 typedef struct {
   char *id;
   bool logged_in;
@@ -24,6 +32,9 @@ typedef struct {
   char nickname[16];
   int queue_id;
   long last_seen;
+  // Things for keeping track of the saved messages
+  saved_message_t saved_messages[20];
+  int saved_message_count;
 } Client;
 
 typedef struct {
@@ -36,7 +47,7 @@ static void handle_hearbeat_timeouts(Client *clients, int client_count,
                                      int semaphore_id) {
   struct sembuf sem_op = {
       .sem_num = 0,
-      .sem_op = 1,
+      .sem_op = -1,
       .sem_flg = 0,
   };
   while (1) {
@@ -53,7 +64,7 @@ static void handle_hearbeat_timeouts(Client *clients, int client_count,
         clients[i].queue_id = -1;
       }
     }
-    sem_op.sem_op = -1;
+    sem_op.sem_op = 1;
     semop(semaphore_id, &sem_op, 1);
     sleep(HEARTBEAT_TIMEOUT);
   }
@@ -117,7 +128,7 @@ int main(int argc, char **argv) {
     case Login:
       printf("Received login request for id: %s\n", msgbuf.sender);
       Client *client = NULL;
-      for (int i = 0; i < 1; i++) {
+      for (int i = 0; i < client_count; i++) {
         if (strncmp(clients[i].id, msgbuf.sender, COMMAND_LENGTH) == 0) {
           client = &clients[i];
           break;
@@ -157,6 +168,7 @@ int main(int argc, char **argv) {
           .mtype = Login,
           .stype = ACK_ACCEPTED,
       };
+
       printf("User accepted: %s\n", msgbuf.sender);
       send(msg_queue_id, &response);
       break;
@@ -186,24 +198,102 @@ int main(int argc, char **argv) {
         continue;
       }
 
-      printf("Forwarding message: %s\n", msgbuf.message);
+      // Now we have to decode if we are to forward this message to a user or a
+      // group first character of command indicates that - u or g
+      char target_type = msgbuf.command[0];
+      char target_id[COMMAND_LENGTH];
+      // Skip the first char and a separtor (:)
+      strncpy(target_id, msgbuf.command + 2, COMMAND_LENGTH - 2);
 
-      // TODO: Find the actual recipients, for now broadcast
+      if (target_type == 'u') {
-      msgbuf_t forward_msg = {
+        Client *target_client = NULL;
-          .mtype = Message,
+        for (int i = 0; i < client_count; i++) {
-      };
+          if (strncmp(clients[i].id, target_id, COMMAND_LENGTH) == 0) {
-      strncpy(forward_msg.message, msgbuf.message, MESSAGE_LENGTH);
+            target_client = &clients[i];
-      // Yes, the client sending the message also receives it
+            break;
-      for (int i = 0; i < client_count; i++) {
+          }
-        if (clients[i].logged_in) {
-          send(clients[i].queue_id, &forward_msg);
         }
+
+        if (target_client == NULL) {
+          // Target client not found or not logged in
+          printf("Target client %s not found or not logged in\n", target_id);
+          msgbuf_t response = {
+              .mtype = Message,
+              .stype = ERR_USER_NOT_FOUND,
+          };
+          send(client->queue_id, &response);
+          continue;
+        }
+
+        // Check if the target is online or not, if they are not, store the
+        // message
+        if (!target_client->logged_in) {
+          if (target_client->saved_message_count >= 20) {
+            // Discard the oldest one and shift the rest to make room
+            for (int i = 1; i < target_client->saved_message_count; i++) {
+              target_client->saved_messages[i - 1] =
+                  target_client->saved_messages[i];
+            }
+            saved_message_t *saved_msg =
+                &target_client
+                     ->saved_messages[target_client->saved_message_count - 1];
+            strncpy(saved_msg->sender, client->nickname, COMMAND_LENGTH);
+            strncpy(saved_msg->message, msgbuf.message, MESSAGE_LENGTH);
+            saved_msg->message_id = rand(); // Random id for the message
+            printf("Message saved for offline client %s\n", target_id);
+
+            // Send out an ack for the sender
+            msgbuf_t response = {
+                .mtype = Message,
+                .stype = ACK_ACCEPTED,
+            };
+            send(client->queue_id, &response);
+            continue;
+          }
+
+          saved_message_t *saved_msg =
+              &target_client
+                   ->saved_messages[target_client->saved_message_count++];
+          strncpy(saved_msg->sender, client->nickname, COMMAND_LENGTH);
+          strncpy(saved_msg->message, msgbuf.message, MESSAGE_LENGTH);
+          saved_msg->message_id = rand(); // Random id for the message
+
+          msgbuf_t response = {
+              .mtype = Message,
+              .stype = ACK_ACCEPTED,
+          };
+          send(client->queue_id, &response);
+          printf("Message saved for offline client %s\n", target_id);
+          continue;
+        }
+
+        printf("Forwarding message to user %s: %s\n", target_client->id,
+               msgbuf.message);
+        msgbuf_t forward_msg = {
+            .mtype = Message,
+            .sender = "",
+        };
+        strncpy(forward_msg.sender, client->nickname, COMMAND_LENGTH);
+        strncpy(forward_msg.message, msgbuf.message, MESSAGE_LENGTH);
+        send(target_client->queue_id, &forward_msg);
+
+        forward_msg.stype = ACK_ACCEPTED;
+        forward_msg.mtype = Signal;
+        send(client->queue_id, &forward_msg);
+
+        printf("Forwarding message: %s\n", msgbuf.message);
+      } else if (target_type == 'g') {
+        // Forward to a group
+
+      } else {
+        printf("Invalid target type: %c\n", target_type);
+        msgbuf_t response = {
+            .mtype = Message,
+            .stype = ERR_INVALID_FORMAT,
+        };
+        send(client->queue_id, &response);
+        continue;
       }
-
-      forward_msg.stype = ACK_ACCEPTED;
-      forward_msg.mtype = Signal;
-      send(client->queue_id, &forward_msg);
-
       // TODO: Accepted and Delivered ack
       break;
     case Logout:

util/util.c

@@ -0,0 +1,26 @@
+#include <stdlib.h>
+#include <string.h>
+
+static char alphs[] = {'-', '_', '0', '1', '2', '3', '4', '5', '6', '7', '8',
+                       '9', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j',
+                       'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u',
+                       'v', 'w', 'x', 'y', 'z', 'A', 'B', 'C', 'D', 'E', 'F',
+                       'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q',
+                       'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', '\0'};
+
+// Generate an id used for messages. Could be less than 16 chars, but thats what
+// fits into the `command` field of `msgbuf_t`.
+void get_id(char *id_buf) {
+  int alph_size = strlen(alphs) - 1;
+
+  for (int i = 0; i < 16; i++) {
+    int random_num;
+    do {
+      random_num = rand();
+    } while (random_num >= (RAND_MAX - RAND_MAX % alph_size));
+
+    random_num %= alph_size;
+    id_buf[i] = alphs[random_num];
+  }
+  id_buf[15] = '\0';
+}

util/util.h

@@ -0,0 +1 @@
+void get_id(char *id_buf);