2f75bae1 |
1 | /* |
2 | * Networking abstraction in PuTTY. |
3 | * |
4 | * The way this works is: a back end can choose to open any number |
5 | * of sockets - including zero, which might be necessary in some. |
6 | * It can register a function to be called when data comes in on |
7 | * any given one, and it can call the networking abstraction to |
8 | * send data without having to worry about blocking. The stuff |
9 | * behind the abstraction takes care of selects and nonblocking |
10 | * writes and all that sort of painful gubbins. |
2f75bae1 |
11 | */ |
12 | |
49bad831 |
13 | #ifndef PUTTY_NETWORK_H |
14 | #define PUTTY_NETWORK_H |
15 | |
2f75bae1 |
16 | typedef struct Socket_tag *Socket; |
17 | typedef struct SockAddr_tag *SockAddr; |
2c94fd1c |
18 | |
19 | /* |
20 | * This is the function a client must register with each socket, to |
21 | * receive data coming in on that socket. The parameter `urgent' |
22 | * decides the meaning of `data' and `len': |
23 | * |
24 | * - urgent==0. `data' points to `len' bytes of perfectly ordinary |
25 | * data. |
26 | * |
27 | * - urgent==1. `data' points to `len' bytes of data, which were |
28 | * read from before an Urgent pointer. |
29 | * |
30 | * - urgent==2. `data' points to `len' bytes of data, the first of |
31 | * which was the one at the Urgent mark. |
32 | * |
33 | * - urgent==3. An error has occurred on the socket. `data' points |
34 | * to an error string, and `len' points to an error code. |
35 | */ |
2f75bae1 |
36 | typedef int (*sk_receiver_t)(Socket s, int urgent, char *data, int len); |
37 | |
38 | void sk_init(void); /* called once at program startup */ |
39 | |
40 | SockAddr sk_namelookup(char *host, char **canonicalname); |
41 | void sk_addr_free(SockAddr addr); |
42 | |
c91409da |
43 | Socket sk_new(SockAddr addr, int port, int privport, sk_receiver_t receiver); |
2f75bae1 |
44 | void sk_close(Socket s); |
45 | void sk_write(Socket s, char *buf, int len); |
46 | void sk_write_oob(Socket s, char *buf, int len); |
47 | |
48 | /* |
49 | * Each socket abstraction contains a `void *' private field in |
50 | * which the client can keep state. |
51 | */ |
52 | void sk_set_private_ptr(Socket s, void *ptr); |
53 | void *sk_get_private_ptr(Socket s); |
54 | |
55 | /* |
56 | * Special error values are returned from sk_namelookup and sk_new |
57 | * if there's a problem. These functions extract an error message, |
58 | * or return NULL if there's no problem. |
59 | */ |
60 | char *sk_addr_error(SockAddr addr); |
61 | char *sk_socket_error(Socket addr); |
49bad831 |
62 | |
63 | #endif |