Implement file transfer queue for offline friends

File transfers initiated for offline friends are now
added to a queue and initiated all at once when the friend
appears online.

src/chat.c

@@ -248,6 +248,7 @@ static void chat_onConnectionChange(ToxWindow *self, Tox *m, uint32_t num, Tox_C
 
     if (prev_status == TOX_CONNECTION_NONE) {
         chat_resume_file_senders(self, m, num);
+        file_send_queue_check(self, m, self->num);
 
         msg = "has come online";
         line_info_add(self, true, nick, NULL, CONNECTION, 0, GREEN, msg);

src/chat_commands.c

@@ -54,7 +54,13 @@ void cmd_cancelfile(WINDOW *window, ToxWindow *self, Tox *m, int argc, char (*ar
         return;
     }
 
-    struct FileTransfer *ft = NULL;
+    // first check transfer queue
+    if (file_send_queue_remove(self->num, idx) == 0) {
+        line_info_add(self, false, NULL, NULL, SYS_MSG, 0, 0, "Pending file transfer removed from queue");
+        return;
+    }
+
+    FileTransfer *ft = NULL;
 
     /* cancel an incoming file transfer */
     if (strcasecmp(inoutstr, "in") == 0) {
@@ -239,7 +245,7 @@ void cmd_savefile(WINDOW *window, ToxWindow *self, Tox *m, int argc, char (*argv
         return;
     }
 
-    struct FileTransfer *ft = get_file_transfer_struct_index(self->num, idx, FILE_TRANSFER_RECV);
+    FileTransfer *ft = get_file_transfer_struct_index(self->num, idx, FILE_TRANSFER_RECV);
 
     if (!ft) {
         line_info_add(self, false, NULL, NULL, SYS_MSG, 0, 0, "No pending file transfers with that ID.");
@@ -324,7 +330,7 @@ void cmd_sendfile(WINDOW *window, ToxWindow *self, Tox *m, int argc, char (*argv
     FILE *file_to_send = fopen(path, "r");
 
     if (file_to_send == NULL) {
-        line_info_add(self, false, NULL, NULL, SYS_MSG, 0, 0, "File not found.");
+        line_info_add(self, false, NULL, NULL, SYS_MSG, 0, 0, "File `%s` not found.", path);
         return;
     }
 
@@ -347,7 +353,7 @@ void cmd_sendfile(WINDOW *window, ToxWindow *self, Tox *m, int argc, char (*argv
         goto on_send_error;
     }
 
-    struct FileTransfer *ft = new_file_transfer(self, self->num, filenum, FILE_TRANSFER_SEND, TOX_FILE_KIND_DATA);
+    FileTransfer *ft = new_file_transfer(self, self->num, filenum, FILE_TRANSFER_SEND, TOX_FILE_KIND_DATA);
 
     if (!ft) {
         err = TOX_ERR_FILE_SEND_TOO_MANY;
@@ -367,29 +373,62 @@ void cmd_sendfile(WINDOW *window, ToxWindow *self, Tox *m, int argc, char (*argv
 
 on_send_error:
 
+    fclose(file_to_send);
+
     switch (err) {
-        case TOX_ERR_FILE_SEND_FRIEND_NOT_FOUND:
+        case TOX_ERR_FILE_SEND_FRIEND_NOT_FOUND: {
             errmsg = "File transfer failed: Invalid friend.";
             break;
+        }
 
-        case TOX_ERR_FILE_SEND_FRIEND_NOT_CONNECTED:
+        case TOX_ERR_FILE_SEND_FRIEND_NOT_CONNECTED: {
-            errmsg = "File transfer failed: Friend is offline.";
+            int queue_idx = file_send_queue_add(self->num, path, path_len);
+
+            char msg[MAX_STR_SIZE];
+
+            switch (queue_idx) {
+                case -1: {
+                    snprintf(msg, sizeof(msg), "Invalid file name: path is null or length is zero.");
                     break;
+                }
 
-        case TOX_ERR_FILE_SEND_NAME_TOO_LONG:
+                case -2: {
+                    snprintf(msg, sizeof(msg), "File name is too long.");
+                    break;
+                }
+
+                case -3: {
+                    snprintf(msg, sizeof(msg), "File send queue is full.");
+                    break;
+                }
+
+                default: {
+                    snprintf(msg, sizeof(msg), "File transfer queued. Type \"/cancel out %d\" to cancel.", queue_idx);
+                    break;
+                }
+            }
+
+            line_info_add(self, false, NULL, NULL, SYS_MSG, 0, 0, "%s", msg);
+
+            return;
+        }
+
+        case TOX_ERR_FILE_SEND_NAME_TOO_LONG: {
             errmsg = "File transfer failed: Filename is too long.";
             break;
+        }
 
-        case TOX_ERR_FILE_SEND_TOO_MANY:
+        case TOX_ERR_FILE_SEND_TOO_MANY: {
             errmsg = "File transfer failed: Too many concurrent file transfers.";
             break;
+        }
 
-        default:
+        default: {
             errmsg = "File transfer failed.";
             break;
         }
+    }
 
     line_info_add(self, false, NULL, NULL, SYS_MSG, 0, 0, "%s", errmsg);
     tox_file_control(m, self->num, filenum, TOX_FILE_CONTROL_CANCEL, NULL);
-    fclose(file_to_send);
 }

src/file_transfers.c

@@ -25,6 +25,7 @@
 #include <time.h>
 #include <unistd.h>
 
+#include "execute.h"
 #include "file_transfers.h"
 #include "friendlist.h"
 #include "line_info.h"
@@ -98,7 +99,7 @@ void print_progress_bar(ToxWindow *self, double bps, double pct_done, uint32_t l
     free(full_line);
 }
 
-static void refresh_progress_helper(ToxWindow *self, struct FileTransfer *ft)
+static void refresh_progress_helper(ToxWindow *self, FileTransfer *ft)
 {
     if (ft->state == FILE_TRANSFER_INACTIVE) {
         return;
@@ -126,8 +127,8 @@ bool refresh_file_transfer_progress(ToxWindow *self, uint32_t friendnumber)
     bool active = false;
 
     for (size_t i = 0; i < MAX_FILES; ++i) {
-        struct FileTransfer *ft_r = &Friends.list[friendnumber].file_receiver[i];
+        FileTransfer *ft_r = &Friends.list[friendnumber].file_receiver[i];
-        struct FileTransfer *ft_s = &Friends.list[friendnumber].file_sender[i];
+        FileTransfer *ft_s = &Friends.list[friendnumber].file_sender[i];
 
         refresh_progress_helper(self, ft_r);
         refresh_progress_helper(self, ft_s);
@@ -140,9 +141,9 @@ bool refresh_file_transfer_progress(ToxWindow *self, uint32_t friendnumber)
     return active;
 }
 
-static void clear_file_transfer(struct FileTransfer *ft)
+static void clear_file_transfer(FileTransfer *ft)
 {
-    *ft = (struct FileTransfer) {
+    *ft = (FileTransfer) {
         0
     };
 }
@@ -150,16 +151,16 @@ static void clear_file_transfer(struct FileTransfer *ft)
 /* Returns a pointer to friendnumber's FileTransfer struct associated with filenumber.
  * Returns NULL if filenumber is invalid.
  */
-struct FileTransfer *get_file_transfer_struct(uint32_t friendnumber, uint32_t filenumber)
+FileTransfer *get_file_transfer_struct(uint32_t friendnumber, uint32_t filenumber)
 {
     for (size_t i = 0; i < MAX_FILES; ++i) {
-        struct FileTransfer *ft_send = &Friends.list[friendnumber].file_sender[i];
+        FileTransfer *ft_send = &Friends.list[friendnumber].file_sender[i];
 
         if (ft_send->state != FILE_TRANSFER_INACTIVE && ft_send->filenumber == filenumber) {
             return ft_send;
         }
 
-        struct FileTransfer *ft_recv = &Friends.list[friendnumber].file_receiver[i];
+        FileTransfer *ft_recv = &Friends.list[friendnumber].file_receiver[i];
 
         if (ft_recv->state != FILE_TRANSFER_INACTIVE && ft_recv->filenumber == filenumber) {
             return ft_recv;
@@ -172,7 +173,7 @@ struct FileTransfer *get_file_transfer_struct(uint32_t friendnumber, uint32_t fi
 /* Returns a pointer to the FileTransfer struct associated with index with the direction specified.
  * Returns NULL on failure.
  */
-struct FileTransfer *get_file_transfer_struct_index(uint32_t friendnumber, uint32_t index,
+FileTransfer *get_file_transfer_struct_index(uint32_t friendnumber, uint32_t index,
         FILE_TRANSFER_DIRECTION direction)
 {
     if (direction != FILE_TRANSFER_RECV && direction != FILE_TRANSFER_SEND) {
@@ -180,7 +181,7 @@ struct FileTransfer *get_file_transfer_struct_index(uint32_t friendnumber, uint3
     }
 
     for (size_t i = 0; i < MAX_FILES; ++i) {
-        struct FileTransfer *ft = direction == FILE_TRANSFER_SEND ?
+        FileTransfer *ft = direction == FILE_TRANSFER_SEND ?
                            &Friends.list[friendnumber].file_sender[i] :
                            &Friends.list[friendnumber].file_receiver[i];
 
@@ -195,10 +196,10 @@ struct FileTransfer *get_file_transfer_struct_index(uint32_t friendnumber, uint3
 /* Returns a pointer to an unused file sender.
  * Returns NULL if all file senders are in use.
  */
-static struct FileTransfer *new_file_sender(ToxWindow *window, uint32_t friendnumber, uint32_t filenumber, uint8_t type)
+static FileTransfer *new_file_sender(ToxWindow *window, uint32_t friendnumber, uint32_t filenumber, uint8_t type)
 {
     for (size_t i = 0; i < MAX_FILES; ++i) {
-        struct FileTransfer *ft = &Friends.list[friendnumber].file_sender[i];
+        FileTransfer *ft = &Friends.list[friendnumber].file_sender[i];
 
         if (ft->state == FILE_TRANSFER_INACTIVE) {
             clear_file_transfer(ft);
@@ -218,11 +219,11 @@ static struct FileTransfer *new_file_sender(ToxWindow *window, uint32_t friendnu
 /* Returns a pointer to an unused file receiver.
  * Returns NULL if all file receivers are in use.
  */
-static struct FileTransfer *new_file_receiver(ToxWindow *window, uint32_t friendnumber, uint32_t filenumber,
+static FileTransfer *new_file_receiver(ToxWindow *window, uint32_t friendnumber, uint32_t filenumber,
                                        uint8_t type)
 {
     for (size_t i = 0; i < MAX_FILES; ++i) {
-        struct FileTransfer *ft = &Friends.list[friendnumber].file_receiver[i];
+        FileTransfer *ft = &Friends.list[friendnumber].file_receiver[i];
 
         if (ft->state == FILE_TRANSFER_INACTIVE) {
             clear_file_transfer(ft);
@@ -242,7 +243,7 @@ static struct FileTransfer *new_file_receiver(ToxWindow *window, uint32_t friend
 /* Initializes an unused file transfer and returns its pointer.
  * Returns NULL on failure.
  */
-struct FileTransfer *new_file_transfer(ToxWindow *window, uint32_t friendnumber, uint32_t filenumber,
+FileTransfer *new_file_transfer(ToxWindow *window, uint32_t friendnumber, uint32_t filenumber,
                                 FILE_TRANSFER_DIRECTION direction, uint8_t type)
 {
     if (direction == FILE_TRANSFER_RECV) {
@@ -256,13 +257,83 @@ struct FileTransfer *new_file_transfer(ToxWindow *window, uint32_t friendnumber,
     return NULL;
 }
 
+int file_send_queue_add(uint32_t friendnumber, const char *file_path, size_t length)
+{
+    if (length == 0 || file_path == NULL) {
+        return -1;
+    }
+
+    if (length > TOX_MAX_FILENAME_LENGTH) {
+        return -2;
+    }
+
+    for (size_t i = 0; i < MAX_FILES; ++i) {
+        PendingFileTransfer *pending_slot = &Friends.list[friendnumber].file_send_queue[i];
+
+        if (pending_slot->pending) {
+            continue;
+        }
+
+        pending_slot->pending = true;
+
+        memcpy(pending_slot->file_path, file_path, length);
+        pending_slot->file_path[length] = 0;
+        pending_slot->length = length;
+
+        return i;
+    }
+
+    return -3;
+}
+
+#define FILE_TRANSFER_SEND_CMD "/sendfile "
+#define FILE_TRANSFER_SEND_LEN (sizeof(FILE_TRANSFER_SEND_CMD) - 1)
+
+void file_send_queue_check(ToxWindow *self, Tox *m, uint32_t friendnumber)
+{
+    for (size_t i = 0; i < MAX_FILES; ++i) {
+        PendingFileTransfer *pending_slot = &Friends.list[friendnumber].file_send_queue[i];
+
+        if (!pending_slot->pending) {
+            continue;
+        }
+
+        char command[TOX_MAX_FILENAME_LENGTH + FILE_TRANSFER_SEND_LEN + 1];
+        snprintf(command, sizeof(command), "%s%s", FILE_TRANSFER_SEND_CMD, pending_slot->file_path);
+
+        execute(self->window, self, m, command, CHAT_COMMAND_MODE);
+
+        *pending_slot = (PendingFileTransfer) {
+            0,
+        };
+    }
+}
+
+int file_send_queue_remove(uint32_t friendnumber, size_t index)
+{
+    if (index >= MAX_FILES) {
+        return -1;
+    }
+
+    PendingFileTransfer *pending_slot = &Friends.list[friendnumber].file_send_queue[index];
+
+    if (!pending_slot->pending) {
+        return -1;
+    }
+
+    *pending_slot = (PendingFileTransfer) {
+        0,
+    };
+
+    return 0;
+}
 
 /* Closes file transfer ft.
  *
  * Set CTRL to -1 if we don't want to send a control signal.
  * Set message or self to NULL if we don't want to display a message.
  */
-void close_file_transfer(ToxWindow *self, Tox *m, struct FileTransfer *ft, int CTRL, const char *message,
+void close_file_transfer(ToxWindow *self, Tox *m, FileTransfer *ft, int CTRL, const char *message,
                          Notification sound_type)
 {
     if (!ft) {
@@ -298,7 +369,7 @@ void close_file_transfer(ToxWindow *self, Tox *m, struct FileTransfer *ft, int C
 void kill_avatar_file_transfers_friend(Tox *m, uint32_t friendnumber)
 {
     for (size_t i = 0; i < MAX_FILES; ++i) {
-        struct FileTransfer *ft = &Friends.list[friendnumber].file_sender[i];
+        FileTransfer *ft = &Friends.list[friendnumber].file_sender[i];
 
         if (ft->file_type == TOX_FILE_KIND_AVATAR) {
             close_file_transfer(NULL, m, ft, TOX_FILE_CONTROL_CANCEL, NULL, silent);
@@ -312,6 +383,7 @@ void kill_all_file_transfers_friend(Tox *m, uint32_t friendnumber)
     for (size_t i = 0; i < MAX_FILES; ++i) {
         close_file_transfer(NULL, m, &Friends.list[friendnumber].file_sender[i], TOX_FILE_CONTROL_CANCEL, NULL, silent);
         close_file_transfer(NULL, m, &Friends.list[friendnumber].file_receiver[i], TOX_FILE_CONTROL_CANCEL, NULL, silent);
+        file_send_queue_remove(friendnumber, i);
     }
 }
 

src/file_transfers.h

@@ -29,9 +29,9 @@
 #include "toxic.h"
 #include "windows.h"
 
-#define KiB 1024
+#define KiB (uint32_t)  1024
-#define MiB 1048576       /* 1024^2 */
+#define MiB (uint32_t) (1024 << 10)  /* 1024^2 */
-#define GiB 1073741824    /* 1024^3 */
+#define GiB (uint32_t) (1024 << 20)  /* 1024^3 */
 
 #define MAX_FILES 32
 
@@ -47,7 +47,7 @@ typedef enum FILE_TRANSFER_DIRECTION {
     FILE_TRANSFER_RECV
 } FILE_TRANSFER_DIRECTION;
 
-struct FileTransfer {
+typedef struct FileTransfer {
     ToxWindow *window;
     FILE *file;
     FILE_TRANSFER_STATE state;
@@ -63,7 +63,15 @@ struct FileTransfer {
     time_t   last_line_progress;   /* The last time we updated the progress bar */
     uint32_t line_id;
     uint8_t  file_id[TOX_FILE_ID_LENGTH];
-};
+} FileTransfer;
+
+typedef struct PendingFileTransfer {
+    char      file_path[TOX_MAX_FILENAME_LENGTH + 1];
+    size_t    length;
+    uint32_t  friendnumber;
+    bool      pending;
+} PendingFileTransfer;
+
 
 /* creates initial progress line that will be updated during file transfer.
    progline must be at lesat MAX_STR_SIZE bytes */
@@ -96,6 +104,31 @@ struct FileTransfer *get_file_transfer_struct_index(uint32_t friendnumber, uint3
 struct FileTransfer *new_file_transfer(ToxWindow *window, uint32_t friendnumber, uint32_t filenumber,
                                        FILE_TRANSFER_DIRECTION direction, uint8_t type);
 
+/* Adds a file designated by `file_path` of length `length` to the file transfer queue.
+ *
+ * Items in this queue will be automatically sent to the contact designated by `friendnumber`
+ * as soon as they appear online. The item will then be removed from the queue whether
+ * or not the transfer successfully initiates.
+ *
+ * If the ToxWindow associated with this friend is closed, all queued items will be
+ * discarded.
+ *
+ * Return the queue index on success.
+ * Return -1 if the length is invalid.
+ * Return -2 if the send queue is full.
+ */
+int file_send_queue_add(uint32_t friendnumber, const char *file_path, size_t length);
+
+/* Initiates all file transfers from the file send queue for friend designated by `friendnumber`. */
+void file_send_queue_check(ToxWindow *self, Tox *m, uint32_t friendnumber);
+
+/* Removes the `index`-th item from the file send queue for `friendnumber`.
+ *
+ * Return 0 if a pending transfer was successfully removed
+ * Return -1 if index does not designate a pending file transfer.
+ */
+int file_send_queue_remove(uint32_t friendnumber, size_t index);
+
 /* Closes file transfer ft.
  *
  * Set CTRL to -1 if we don't want to send a control signal.

src/friendlist.c

@@ -1107,14 +1107,14 @@ static void friendlist_onDraw(ToxWindow *self, Tox *m)
 
     /* Determine which portion of friendlist to draw based on current position */
     pthread_mutex_lock(&Winthread.lock);
-    int page = Friends.num_selected / (y2 - FLIST_OFST);
+    const int page = Friends.num_selected / (y2 - FLIST_OFST);
     pthread_mutex_unlock(&Winthread.lock);
 
-    int start = (y2 - FLIST_OFST) * page;
+    const int start = (y2 - FLIST_OFST) * page;
-    int end = y2 - FLIST_OFST + start;
+    const int end = y2 - FLIST_OFST + start;
 
     pthread_mutex_lock(&Winthread.lock);
-    size_t num_friends = Friends.num_friends;
+    const size_t num_friends = Friends.num_friends;
     pthread_mutex_unlock(&Winthread.lock);
 
     int i;

src/friendlist.h

@@ -79,8 +79,9 @@ typedef struct {
     struct GameInvite game_invite;
 #endif
 
-    struct FileTransfer file_receiver[MAX_FILES];
+    FileTransfer file_receiver[MAX_FILES];
-    struct FileTransfer file_sender[MAX_FILES];
+    FileTransfer file_sender[MAX_FILES];
+    PendingFileTransfer file_send_queue[MAX_FILES];
 } ToxicFriend;
 
 typedef struct {

src/windows.c

@@ -244,7 +244,7 @@ void on_file_chunk_request(Tox *m, uint32_t friendnumber, uint32_t filenumber, u
 {
     UNUSED_VAR(userdata);
 
-    struct FileTransfer *ft = get_file_transfer_struct(friendnumber, filenumber);
+    FileTransfer *ft = get_file_transfer_struct(friendnumber, filenumber);
 
     if (!ft) {
         return;
@@ -267,7 +267,7 @@ void on_file_recv_chunk(Tox *m, uint32_t friendnumber, uint32_t filenumber, uint
 {
     UNUSED_VAR(userdata);
 
-    struct FileTransfer *ft = get_file_transfer_struct(friendnumber, filenumber);
+    FileTransfer *ft = get_file_transfer_struct(friendnumber, filenumber);
 
     if (!ft) {
         return;
@@ -285,7 +285,7 @@ void on_file_recv_control(Tox *m, uint32_t friendnumber, uint32_t filenumber, To
 {
     UNUSED_VAR(userdata);
 
-    struct FileTransfer *ft = get_file_transfer_struct(friendnumber, filenumber);
+    FileTransfer *ft = get_file_transfer_struct(friendnumber, filenumber);
 
     if (!ft) {
         return;