mdw@git.distorted.org.uk Git - sgt/putty/blob - contrib/cygtermd/main.c

   1 /*
   2  * Main program.
   3  */
   4
   5 #include <stdio.h>
   6 #include <stdlib.h>
   7 #include <stddef.h>
   8 #include <stdarg.h>
   9 #include <signal.h>
  10 #include <string.h>
  11 #include <errno.h>
  12
  13 #include <unistd.h>
  14 #include <sys/types.h>
  15 #include <sys/wait.h>
  16
  17 #include "sel.h"
  18 #include "pty.h"
  19 #include "telnet.h"
  20
  21 int signalpipe[2];
  22
  23 sel *asel;
  24 sel_rfd *netr, *ptyr, *sigr;
  25 int ptyfd;
  26 sel_wfd *netw, *ptyw;
  27 Telnet telnet;
  28
  29 #define BUF 65536
  30
  31 void sigchld(int signum)
  32 {
  33     write(signalpipe[1], "C", 1);
  34 }
  35
  36 void fatal(const char *fmt, ...)
  37 {
  38     va_list ap;
  39     fprintf(stderr, "FIXME: ");
  40     va_start(ap, fmt);
  41     vfprintf(stderr, fmt, ap);
  42     va_end(ap);
  43     fprintf(stderr, "\n");
  44     exit(1);
  45 }
  46
  47 void net_readdata(sel_rfd *rfd, void *data, size_t len)
  48 {
  49     if (len == 0)
  50         exit(0);                       /* EOF on network - client went away */
  51     telnet_from_net(telnet, data, len);
  52     if (sel_write(netw, NULL, 0) > BUF)
  53         sel_rfd_freeze(ptyr);
  54     if (sel_write(ptyw, NULL, 0) > BUF)
  55         sel_rfd_freeze(netr);
  56 }
  57
  58 void net_readerr(sel_rfd *rfd, int error)
  59 {
  60     fprintf(stderr, "standard input: read: %s\n", strerror(errno));
  61     exit(1);
  62 }
  63
  64 void net_written(sel_wfd *wfd, size_t bufsize)
  65 {
  66     if (bufsize < BUF)
  67         sel_rfd_unfreeze(ptyr);
  68 }
  69
  70 void net_writeerr(sel_wfd *wfd, int error)
  71 {
  72     fprintf(stderr, "standard input: write: %s\n", strerror(errno));
  73     exit(1);
  74 }
  75
  76 void pty_readdata(sel_rfd *rfd, void *data, size_t len)
  77 {
  78     if (len == 0)
  79         exit(0);                       /* EOF on pty */
  80     telnet_from_pty(telnet, data, len);
  81     if (sel_write(netw, NULL, 0) > BUF)
  82         sel_rfd_freeze(ptyr);
  83     if (sel_write(ptyw, NULL, 0) > BUF)
  84         sel_rfd_freeze(netr);
  85 }
  86
  87 void pty_readerr(sel_rfd *rfd, int error)
  88 {
  89     if (error == EIO)                  /* means EOF, on a pty */
  90         exit(0);
  91     fprintf(stderr, "pty: read: %s\n", strerror(errno));
  92     exit(1);
  93 }
  94
  95 void pty_written(sel_wfd *wfd, size_t bufsize)
  96 {
  97     if (bufsize < BUF)
  98         sel_rfd_unfreeze(netr);
  99 }
 100
 101 void pty_writeerr(sel_wfd *wfd, int error)
 102 {
 103     fprintf(stderr, "pty: write: %s\n", strerror(errno));
 104     exit(1);
 105 }
 106
 107 void sig_readdata(sel_rfd *rfd, void *data, size_t len)
 108 {
 109     char *p = data;
 110
 111     while (len > 0) {
 112         if (*p == 'C') {
 113             int status;
 114             pid_t pid = waitpid(-1, &status, WNOHANG);
 115             if (WIFEXITED(status) || WIFSIGNALED(status))
 116                 exit(0);               /* child process vanished */
 117         }
 118     }
 119 }
 120
 121 void sig_readerr(sel_rfd *rfd, int error)
 122 {
 123     fprintf(stderr, "signal pipe: read: %s\n", strerror(errno));
 124     exit(1);
 125 }
 126
 127 int main(int argc, char **argv)
 128 {
 129     int ret;
 130     int shell_started = 0;
 131     char *directory = NULL;
 132     char **program_args = NULL;
 133
 134     if (argc > 1 && argv[1][0]) {
 135         directory = argv[1];
 136         argc--, argv++;
 137     }
 138     if (argc > 1) {
 139         program_args = argv + 1;
 140     }
 141
 142     pty_preinit();
 143
 144     asel = sel_new(NULL);
 145     netr = sel_rfd_add(asel, 0, net_readdata, net_readerr, NULL);
 146     netw = sel_wfd_add(asel, 1, net_written, net_writeerr, NULL);
 147     ptyr = sel_rfd_add(asel, -1, pty_readdata, pty_readerr, NULL);
 148     ptyw = sel_wfd_add(asel, -1, pty_written, pty_writeerr, NULL);
 149
 150     telnet = telnet_new(netw, ptyw);
 151
 152     if (pipe(signalpipe) < 0) {
 153         perror("pipe");
 154         return 1;
 155     }
 156     sigr = sel_rfd_add(asel, signalpipe[0], sig_readdata,
 157                        sig_readerr, NULL);
 158
 159     signal(SIGCHLD, sigchld);
 160
 161     do {
 162         struct shell_data shdata;
 163
 164         ret = sel_iterate(asel, -1);
 165         if (!shell_started && telnet_shell_ok(telnet, &shdata)) {
 166             ptyfd = run_program_in_pty(&shdata, directory, program_args);
 167             sel_rfd_setfd(ptyr, ptyfd);
 168             sel_wfd_setfd(ptyw, ptyfd);
 169             shell_started = 1;
 170         }
 171     } while (ret == 0);
 172
 173     return 0;
 174 }