vsyssh/vsyssh.c

   1 /* gcc -Wall -O2 -g chpid.c -o chpid */
   2 #define _XOPEN_SOURCE
   3 #define _XOPEN_SOURCE_EXTENDED
   4 #define _SVID_SOURCE
   5 #define _GNU_SOURCE
   6 #include <stdio.h>
   7 #include <errno.h>
   8 #include <string.h>
   9 #include <signal.h>
  10 #include <stdlib.h>
  11 #include <sys/types.h>
  12 #include <sys/stat.h>
  13 #include <sys/syscall.h>
  14 #include <sys/wait.h>
  15 #include <sys/time.h>
  16 #include <sys/select.h>
  17 #include <sys/resource.h>
  18 #include <sys/mount.h>
  19 #include <sys/vfs.h>
  20 #include <fcntl.h>
  21 #include <unistd.h>
  22 #include <sched.h>
  23 #include <stdarg.h>
  24 #include <dirent.h>
  25
  26 void pipe_handler (int sig) {
  27         printf("SIGPIPE");
  28 }
  29
  30 int main(int argc, char **argv, char **envp)
  31 {
  32         if (argc<2) {
  33                 printf("Usage: vsyssh <vsys entry> [cmd]\n");
  34                 exit(1);
  35         }
  36         else {
  37                 int vfd0,vfd1;
  38                 char *inf,*outf;
  39                 struct timeval tv;
  40
  41                 signal(SIGPIPE,pipe_handler);
  42                 inf=(char *)malloc(strlen(argv[1])+3);
  43                 outf=(char *)malloc(strlen(argv[1])+4);
  44                 strcpy(inf,argv[1]);
  45                 strcpy(outf,argv[1]);
  46                 strcat(inf,".in");
  47                 strcat(outf,".out");
  48
  49                 vfd0 = open(outf,O_RDONLY|O_NONBLOCK);
  50                 vfd1 = open(inf,O_WRONLY);
  51
  52                 if (vfd0==-1 || vfd1 == -1) {
  53                         printf("Error opening vsys entry %s (%s)\n", argv[1],strerror(errno));
  54                         exit(1);
  55                 }
  56
  57                 if (fcntl(vfd0, F_SETFL, O_RDONLY) == -1) {
  58                         printf("Error making pipe blocking: %m\n");
  59                         exit(1);
  60                 }
  61
  62                 if (argc<3) {
  63                         fd_set set;
  64                         char do_input = 1, do_output = 1;
  65
  66                         while (1)
  67                         {
  68                                 int ret;
  69                                 printf("vsys>");fflush(stdout);
  70                                 FD_ZERO(&set);
  71                                 if (do_input)
  72                                         FD_SET(0, &set);
  73                                 if (do_output)
  74                                         FD_SET(vfd0, &set);
  75                                 ret = select(vfd0+1, &set, NULL, NULL, NULL);
  76                                 if (FD_ISSET(0,&set)) {
  77                                         char lineread[2048];
  78                                         int ret;
  79                                         ret=read(0,lineread,2048);
  80                                         if (ret == 0)
  81                                                 do_input = 0;
  82                                         lineread[ret]='\0';
  83                                         printf ("writing %s\n",lineread);
  84                                         write(vfd1,lineread,ret);
  85                                 }
  86                                 if (FD_ISSET(vfd0,&set)) {
  87                                         char lineread[2048];
  88                                         int ret;
  89                                         ret = read(vfd0,lineread,2048);
  90                                         if (ret == 0)
  91                                                 break;
  92                                         write(1,lineread,ret);
  93                                 }
  94                         }
  95
  96                 }
  97                 else {
  98                         close(0);
  99                         close(1);
 100
 101                         dup2(vfd0,0);
 102                         dup2(vfd1,1);
 103                         execve(argv[2],argv+2,envp);
 104                 }
 105        }
 106
 107        return -1;
 108
 109 }