git.sesse.net Git - pistorm/blob - a314/a314device/sockets.c

   1 /*
   2  * Copyright 2020-2021 Niklas Ekström
   3  */
   4
   5 #include <proto/exec.h>
   6
   7 #include "sockets.h"
   8
   9 struct List active_sockets;
  10
  11 struct Socket *send_queue_head = NULL;
  12 struct Socket *send_queue_tail = NULL;
  13
  14 static UBYTE next_stream_id = 1;
  15
  16 extern void NewList(struct List *l);
  17
  18 void init_sockets()
  19 {
  20         NewList(&active_sockets);
  21 }
  22
  23 struct Socket *find_socket(void *sig_task, ULONG socket)
  24 {
  25         for (struct Node *node = active_sockets.lh_Head; node->ln_Succ != NULL; node = node->ln_Succ)
  26         {
  27                 struct Socket *s = (struct Socket *)node;
  28                 if (s->sig_task == sig_task && s->socket == socket)
  29                         return s;
  30         }
  31         return NULL;
  32 }
  33
  34 struct Socket *find_socket_by_stream_id(UBYTE stream_id)
  35 {
  36         for (struct Node *node = active_sockets.lh_Head; node->ln_Succ != NULL; node = node->ln_Succ)
  37         {
  38                 struct Socket *s = (struct Socket *)node;
  39                 if (s->stream_id == stream_id)
  40                         return s;
  41         }
  42         return NULL;
  43 }
  44
  45 static UBYTE allocate_stream_id()
  46 {
  47         // Bug: If all stream ids are allocated then this loop won't terminate.
  48
  49         while (1)
  50         {
  51                 UBYTE stream_id = next_stream_id;
  52                 next_stream_id += 2;
  53                 if (find_socket_by_stream_id(stream_id) == NULL)
  54                         return stream_id;
  55         }
  56 }
  57
  58 static void free_stream_id(UBYTE stream_id)
  59 {
  60         // Currently do nothing.
  61         // Could speed up allocate_stream_id using a bitmap?
  62 }
  63
  64 struct Socket *create_socket(struct Task *task, ULONG id)
  65 {
  66         struct Socket *s = (struct Socket *)AllocMem(sizeof(struct Socket), MEMF_CLEAR);
  67         s->sig_task = task;
  68         s->socket = id;
  69         s->stream_id = allocate_stream_id();
  70         AddTail(&active_sockets, (struct Node *)s);
  71         return s;
  72 }
  73
  74 void delete_socket(struct Socket *s)
  75 {
  76         Remove((struct Node *)s);
  77         free_stream_id(s->stream_id);
  78         FreeMem(s, sizeof(struct Socket));
  79 }
  80
  81 void add_to_send_queue(struct Socket *s, UWORD required_length)
  82 {
  83         s->send_queue_required_length = required_length;
  84         s->next_in_send_queue = NULL;
  85
  86         if (send_queue_head == NULL)
  87                 send_queue_head = s;
  88         else
  89                 send_queue_tail->next_in_send_queue = s;
  90         send_queue_tail = s;
  91
  92         s->flags |= SOCKET_IN_SEND_QUEUE;
  93 }
  94
  95 void remove_from_send_queue(struct Socket *s)
  96 {
  97         if (s->flags & SOCKET_IN_SEND_QUEUE)
  98         {
  99                 if (send_queue_head == s)
 100                 {
 101                         send_queue_head = s->next_in_send_queue;
 102                         if (send_queue_head == NULL)
 103                                 send_queue_tail = NULL;
 104                 }
 105                 else
 106                 {
 107                         struct Socket *curr = send_queue_head;
 108                         while (curr->next_in_send_queue != s)
 109                                 curr = curr->next_in_send_queue;
 110
 111                         curr->next_in_send_queue = s->next_in_send_queue;
 112                         if (send_queue_tail == s)
 113                                 send_queue_tail = curr;
 114                 }
 115
 116                 s->next_in_send_queue = NULL;
 117                 s->flags &= ~SOCKET_IN_SEND_QUEUE;
 118         }
 119 }