source/misc.cpp

   1 #include <sys/wait.h>
   2 #include <fcntl.h>
   3 #include <cstdlib>
   4 #include <cstring>
   5 #include <unistd.h>
   6 #include <msp/io/print.h>
   7 #include "misc.h"
   8
   9 using namespace std;
  10 using namespace Msp;
  11
  12 string run_command(const StringList &argv, int *status)
  13 {
  14         int pfd[2];
  15         pipe(pfd);
  16
  17         string result;
  18
  19         pid_t pid = fork();
  20         if(pid==0)
  21         {
  22                 char *argv_[argv.size()+1];
  23
  24                 unsigned j = 0;
  25                 for(StringList::const_iterator i=argv.begin(); i!=argv.end(); ++i)
  26                         argv_[j++] = strdup(i->c_str());
  27                 argv_[j] = 0;
  28
  29                 close(pfd[0]);
  30                 dup2(pfd[1], 1);
  31                 close(pfd[1]);
  32                 int devnull = open("/dev/null", O_WRONLY);
  33                 dup2(devnull, 2);
  34                 close(devnull);
  35
  36                 execvp(argv_[0], argv_);
  37                 ::exit(1);
  38         }
  39         else if(pid==-1)
  40                 IO::print(IO::cerr, "Failed to execute %s\n", argv.front());
  41         else
  42         {
  43                 close(pfd[1]);
  44                 while(1)
  45                 {
  46                         char buf[1024];
  47                         int len = read(pfd[0], buf, sizeof(buf));
  48                         if(len<=0)
  49                         {
  50                                 int s;
  51                                 if(waitpid(pid, &s, WNOHANG))
  52                                 {
  53                                         if(status)
  54                                         {
  55                                                 if(WIFEXITED(s))
  56                                                         *status = WEXITSTATUS(s);
  57                                                 else
  58                                                         *status = -1;
  59                                         }
  60                                         break;
  61                                 }
  62                         }
  63                         else
  64                                 result.append(buf, len);
  65                 }
  66                 close(pfd[0]);
  67         }
  68
  69         return result;
  70 }
  71
  72