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[200];
  94         sprintf(buf, "Looking up host \"%.170s\"", host);
  95         logevent(raw->frontend, buf);
  96     }
  97     addr = sk_namelookup(host, realhost);
  98     if ((err = sk_addr_error(addr)))
  99         return err;
 100
 101     if (port < 0)
 102         port = 23;                     /* default telnet port */
 103
 104     /*
 105      * Open socket.
 106      */
 107     {
 108         char buf[200], addrbuf[100];
 109         sk_getaddr(addr, addrbuf, 100);
 110         sprintf(buf, "Connecting to %.100s port %d", addrbuf, port);
 111         logevent(raw->frontend, buf);
 112     }
 113     raw->s = new_connection(addr, *realhost, port, 0, 1, nodelay, (Plug) raw);
 114     if ((err = sk_socket_error(raw->s)))
 115         return err;
 116
 117     sk_addr_free(addr);
 118
 119     return NULL;
 120 }
 121
 122 /*
 123  * Called to send data down the raw connection.
 124  */
 125 static int raw_send(void *handle, char *buf, int len)
 126 {
 127     Raw raw = (Raw) handle;
 128
 129     if (raw->s == NULL)
 130         return 0;
 131
 132     raw->bufsize = sk_write(raw->s, buf, len);
 133
 134     return raw->bufsize;
 135 }
 136
 137 /*
 138  * Called to query the current socket sendability status.
 139  */
 140 static int raw_sendbuffer(void *handle)
 141 {
 142     Raw raw = (Raw) handle;
 143     return raw->bufsize;
 144 }
 145
 146 /*
 147  * Called to set the size of the window
 148  */
 149 static void raw_size(void *handle, int width, int height)
 150 {
 151     /* Do nothing! */
 152     return;
 153 }
 154
 155 /*
 156  * Send raw special codes.
 157  */
 158 static void raw_special(void *handle, Telnet_Special code)
 159 {
 160     /* Do nothing! */
 161     return;
 162 }
 163
 164 static Socket raw_socket(void *handle)
 165 {
 166     Raw raw = (Raw) handle;
 167     return raw->s;
 168 }
 169
 170 static int raw_sendok(void *handle)
 171 {
 172     return 1;
 173 }
 174
 175 static void raw_unthrottle(void *handle, int backlog)
 176 {
 177     Raw raw = (Raw) handle;
 178     sk_set_frozen(raw->s, backlog > RAW_MAX_BACKLOG);
 179 }
 180
 181 static int raw_ldisc(void *handle, int option)
 182 {
 183     if (option == LD_EDIT || option == LD_ECHO)
 184         return 1;
 185     return 0;
 186 }
 187
 188 static void raw_provide_ldisc(void *handle, void *ldisc)
 189 {
 190     /* This is a stub. */
 191 }
 192
 193 static void raw_provide_logctx(void *handle, void *logctx)
 194 {
 195     /* This is a stub. */
 196 }
 197
 198 static int raw_exitcode(void *handle)
 199 {
 200     /* Exit codes are a meaningless concept in the Raw protocol */
 201     return 0;
 202 }
 203
 204 Backend raw_backend = {
 205     raw_init,
 206     raw_send,
 207     raw_sendbuffer,
 208     raw_size,
 209     raw_special,
 210     raw_socket,
 211     raw_exitcode,
 212     raw_sendok,
 213     raw_ldisc,
 214     raw_provide_ldisc,
 215     raw_provide_logctx,
 216     raw_unthrottle,
 217     1
 218 };