cosmopolitan/libc/stdio/system.c

62 lines
3.1 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2020 Justine Alexandra Roberts Tunney │
│ │
│ This program is free software; you can redistribute it and/or modify │
│ it under the terms of the GNU General Public License as published by │
│ the Free Software Foundation; version 2 of the License. │
│ │
│ This program is distributed in the hope that it will be useful, but │
│ WITHOUT ANY WARRANTY; without even the implied warranty of │
│ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU │
│ General Public License for more details. │
│ │
│ You should have received a copy of the GNU General Public License │
│ along with this program; if not, write to the Free Software │
│ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA │
│ 02110-1301 USA │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/bits/weaken.h"
#include "libc/calls/calls.h"
#include "libc/calls/hefty/spawn.h"
#include "libc/dce.h"
#include "libc/errno.h"
#include "libc/paths.h"
#include "libc/runtime/runtime.h"
#include "libc/stdio/stdio.h"
#include "libc/str/str.h"
/**
* Launches program with system command interpreter.
*
* @param cmdline is an interpreted Turing-complete command
* @return -1 if child process couldn't be created, otherwise a wait
* status that can be accessed using macros like WEXITSTATUS(s)
*/
int system(const char *cmdline) {
char comspec[128];
int rc, pid, wstatus;
const char *prog, *arg;
if (weaken(fflush)) weaken(fflush)(NULL);
if (cmdline) {
if ((pid = fork()) == -1) return -1;
if (!pid) {
strcpy(comspec, kNtSystemDirectory);
strcat(comspec, "cmd.exe");
prog = !IsWindows() ? _PATH_BSHELL : comspec;
arg = !IsWindows() ? "-c" : "/C";
execve(prog, (char *const[]){prog, arg, cmdline, NULL}, environ);
_exit(errno);
} else if (wait4(pid, &wstatus, 0, NULL) != -1) {
return wstatus;
} else {
return -1;
}
} else if (IsWindows()) {
return true;
} else {
return fileexists(_PATH_BSHELL);
}
}