apps/lib/libmeinos/execute.c

   1 /*
   2     meinOS - A unix-like x86 microkernel operating system
   3     Copyright (C) 2008  Janosch Gräf <janosch.graef@gmx.net>
   4
   5     This program is free software: you can redistribute it and/or modify
   6     it under the terms of the GNU Lesser General Public License as published by
   7     the Free Software Foundation, either version 3 of the License, or
   8     (at your option) any later version.
   9
  10     This program is distributed in the hope that it will be useful,
  11     but WITHOUT ANY WARRANTY; without even the implied warranty of
  12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13     GNU Lesser General Public License for more details.
  14
  15     You should have received a copy of the GNU Lesser General Public License
  16     along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17 */
  18
  19 #include <sys/types.h>
  20 #include <sys/shm.h>
  21 #include <rpc.h>
  22 #include <misc.h>
  23 #include <string.h>
  24
  25 /**
  26  * Creates a new process from executable file
  27  *  @param path Path to executable
  28  *  @param argv Argument vector
  29  *  @param _stdin Reference for filehandle for stdin of new process
  30  *  @param _stdout Reference for filehandle for stdout of new process
  31  *  @param _stderr Reference for filehandle for stderr of new process
  32  *  @return PID of new process
  33  */
  34 #include <stdio.h>
  35 pid_t execute(const char *path,char *argv[],const char *_stdin,const char *_stdout,const char *_stderr) {
  36   size_t shmsize = sizeof(struct process_data);
  37   int shmid;
  38   struct process_data *data;
  39   size_t i;
  40
  41   if (argv!=NULL) {
  42     for (i=0;argv[i];i++) shmsize += strlen(argv[i])+1;
  43   }
  44   if (_stdin!=NULL) shmsize += strlen(_stdin);
  45   if (_stdout!=NULL) shmsize += strlen(_stdout);
  46   if (_stderr!=NULL) shmsize += strlen(_stderr);
  47   shmid = shmget(IPC_PRIVATE,shmsize,0);
  48
  49   if (shmid!=-1) {
  50     data = shmat(shmid,NULL,0);
  51
  52     if (data!=NULL) {
  53       size_t j = 0;
  54       if (argv!=NULL) {
  55         for (i=0;argv[i];i++) {
  56           strcpy(data->cmdline+j,argv[i]);
  57           j += strlen(data->cmdline+j)+1;
  58         }
  59         data->argc = i;
  60       }
  61       else data->argc = 0;
  62
  63       data->has_stdin = (_stdin!=NULL);
  64       if (_stdin!=NULL) {
  65         strcpy(data->stdio+j,_stdin);
  66         j += strlen(data->stdio+j)+1;
  67       }
  68
  69       data->has_stdout = (_stdout!=NULL);
  70       if (_stdout!=NULL) {
  71         strcpy(data->stdio+j,_stdout);
  72         j += strlen(data->stdio+j)+1;
  73       }
  74
  75       data->has_stderr = (_stderr!=NULL);
  76       if (_stderr!=NULL) {
  77         strcpy(data->stdio+j,_stderr);
  78         j += strlen(data->stdio+j)+1;
  79       }
  80
  81       shmdt(data);
  82
  83       return rpc_call("proc_execute",0,path,shmid);
  84     }
  85   }
  86   return -1;
  87 }