git.distorted.org.uk Git - u/mdw/putty/blob - raw.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3
   4 #include "putty.h"
   5
   6 #ifndef FALSE
   7 #define FALSE 0
   8 #endif
   9 #ifndef TRUE
  10 #define TRUE 1
  11 #endif
  12
  13 #define RAW_MAX_BACKLOG 4096
  14
  15 typedef struct raw_backend_data {
  16     const struct plug_function_table *fn;
  17     /* the above field _must_ be first in the structure */
  18
  19     Socket s;
  20     int bufsize;
  21     void *frontend;
  22 } *Raw;
  23
  24 static void raw_size(void *handle, int width, int height);
  25
  26 static void c_write(Raw raw, char *buf, int len)
  27 {
  28     int backlog = from_backend(raw->frontend, 0, buf, len);
  29     sk_set_frozen(raw->s, backlog > RAW_MAX_BACKLOG);
  30 }
  31
  32 static int raw_closing(Plug plug, char *error_msg, int error_code,
  33                        int calling_back)
  34 {
  35     Raw raw = (Raw) plug;
  36
  37     if (raw->s) {
  38         sk_close(raw->s);
  39         raw->s = NULL;
  40     }
  41     if (error_msg) {
  42         /* A socket error has occurred. */
  43         logevent(raw->frontend, error_msg);
  44         connection_fatal("%s", error_msg);
  45     }                                  /* Otherwise, the remote side closed the connection normally. */
  46     return 0;
  47 }
  48
  49 static int raw_receive(Plug plug, int urgent, char *data, int len)
  50 {
  51     Raw raw = (Raw) plug;
  52     c_write(raw, data, len);
  53     return 1;
  54 }
  55
  56 static void raw_sent(Plug plug, int bufsize)
  57 {
  58     Raw raw = (Raw) plug;
  59     raw->bufsize = bufsize;
  60 }
  61
  62 /*
  63  * Called to set up the raw connection.
  64  *
  65  * Returns an error message, or NULL on success.
  66  *
  67  * Also places the canonical host name into `realhost'. It must be
  68  * freed by the caller.
  69  */
  70 static char *raw_init(void *frontend_handle, void **backend_handle,
  71                       char *host, int port, char **realhost, int nodelay)
  72 {
  73     static const struct plug_function_table fn_table = {
  74         raw_closing,
  75         raw_receive,
  76         raw_sent
  77     };
  78     SockAddr addr;
  79     char *err;
  80     Raw raw;
  81
  82     raw = smalloc(sizeof(*raw));
  83     raw->fn = &fn_table;
  84     raw->s = NULL;
  85     *backend_handle = raw;
  86
  87     raw->frontend = frontend_handle;
  88
  89     /*
  90      * Try to find host.
  91      */
  92     {
  93         char *buf;
  94         buf = dupprintf("Looking up host \"%s\"", host);
  95         logevent(raw->frontend, buf);
  96         sfree(buf);
  97     }
  98     addr = name_lookup(host, port, realhost);
  99     if ((err = sk_addr_error(addr)))
 100         return err;
 101
 102     if (port < 0)
 103         port = 23;                     /* default telnet port */
 104
 105     /*
 106      * Open socket.
 107      */
 108     {
 109         char *buf, addrbuf[100];
 110         sk_getaddr(addr, addrbuf, 100);
 111         buf = dupprintf("Connecting to %s port %d", addrbuf, port);
 112         logevent(raw->frontend, buf);
 113         sfree(buf);
 114     }
 115     raw->s = new_connection(addr, *realhost, port, 0, 1, nodelay, (Plug) raw);
 116     if ((err = sk_socket_error(raw->s)))
 117         return err;
 118
 119     sk_addr_free(addr);
 120
 121     return NULL;
 122 }
 123
 124 /*
 125  * Called to send data down the raw connection.
 126  */
 127 static int raw_send(void *handle, char *buf, int len)
 128 {
 129     Raw raw = (Raw) handle;
 130
 131     if (raw->s == NULL)
 132         return 0;
 133
 134     raw->bufsize = sk_write(raw->s, buf, len);
 135
 136     return raw->bufsize;
 137 }
 138
 139 /*
 140  * Called to query the current socket sendability status.
 141  */
 142 static int raw_sendbuffer(void *handle)
 143 {
 144     Raw raw = (Raw) handle;
 145     return raw->bufsize;
 146 }
 147
 148 /*
 149  * Called to set the size of the window
 150  */
 151 static void raw_size(void *handle, int width, int height)
 152 {
 153     /* Do nothing! */
 154     return;
 155 }
 156
 157 /*
 158  * Send raw special codes.
 159  */
 160 static void raw_special(void *handle, Telnet_Special code)
 161 {
 162     /* Do nothing! */
 163     return;
 164 }
 165
 166 static Socket raw_socket(void *handle)
 167 {
 168     Raw raw = (Raw) handle;
 169     return raw->s;
 170 }
 171
 172 static int raw_sendok(void *handle)
 173 {
 174     return 1;
 175 }
 176
 177 static void raw_unthrottle(void *handle, int backlog)
 178 {
 179     Raw raw = (Raw) handle;
 180     sk_set_frozen(raw->s, backlog > RAW_MAX_BACKLOG);
 181 }
 182
 183 static int raw_ldisc(void *handle, int option)
 184 {
 185     if (option == LD_EDIT || option == LD_ECHO)
 186         return 1;
 187     return 0;
 188 }
 189
 190 static void raw_provide_ldisc(void *handle, void *ldisc)
 191 {
 192     /* This is a stub. */
 193 }
 194
 195 static void raw_provide_logctx(void *handle, void *logctx)
 196 {
 197     /* This is a stub. */
 198 }
 199
 200 static int raw_exitcode(void *handle)
 201 {
 202     /* Exit codes are a meaningless concept in the Raw protocol */
 203     return 0;
 204 }
 205
 206 Backend raw_backend = {
 207     raw_init,
 208     raw_send,
 209     raw_sendbuffer,
 210     raw_size,
 211     raw_special,
 212     raw_socket,
 213     raw_exitcode,
 214     raw_sendok,
 215     raw_ldisc,
 216     raw_provide_ldisc,
 217     raw_provide_logctx,
 218     raw_unthrottle,
 219     1
 220 };