source/misc.cpp

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