jehanne/sys/src/cmd/xargs.c

87 lines
2.0 KiB
C
Raw Normal View History

2018-01-06 01:08:25 +01:00
/*
* This file is part of the UCB release of Plan 9. It is subject to the license
* terms in the LICENSE file found in the top-level directory of this
* distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No
* part of the UCB release of Plan 9, including this file, may be copied,
* modified, propagated, or distributed except according to the terms contained
* in the LICENSE file.
*/
/* Portions of this file are Copyright (C) 2015-2018 Giacomo Tesio <giacomo@tesio.it>
* See /doc/license/gpl-2.0.txt for details about the licensing.
*/
/* Portions of this file are Copyright (C) 9front's team.
* See /doc/license/9front-mit for details about the licensing.
* See http://code.9front.org/hg/plan9front/ for a list of authors.
*/
#include <u.h>
#include <lib9.h>
#include <bio.h>
void
usage(void)
{
fprint(2, "usage: xargs [ -n lines ] [ -p procs ] args ...\n");
exits("usage");
}
void
dowait(void)
{
while(waitpid() != -1)
;
}
void
main(int argc, char **argv)
{
int lines, procs, i, j, run;
char **nargv, **args, **p;
static Biobuf bp;
lines = 10;
procs = 1;
ARGBEGIN {
case 'n': lines = atoi(EARGF(usage())); break;
case 'p': procs = atoi(EARGF(usage())); break;
default: usage();
} ARGEND;
if(argc < 1)
usage();
nargv = malloc(sizeof(char *) * (argc + lines + 1));
if(nargv == nil)
sysfatal("malloc: %r");
memcpy(nargv, argv, sizeof(char *) * argc);
args = nargv + argc;
if(Binit(&bp, 0, OREAD) < 0)
sysfatal("Binit: %r");
atexit(dowait);
for(j = 0, run = 1; run; j++){
if(j >= procs)
waitpid();
memset(args, 0, sizeof(char *) * (lines + 1));
for(i = 0; i < lines; i++)
if((args[i] = Brdstr(&bp, '\n', 1)) == nil){
if(i == 0)
exits(nil);
run = 0;
break;
}
switch(fork()){
case -1:
sysfatal("fork: %r");
case 0:
exec(*nargv, nargv);
if(**nargv != '/' && strncmp(*nargv, "./", 2) != 0 &&
strncmp(*nargv, "../", 3) != 0){
*nargv = smprint("/cmd/%s", *nargv);
exec(*nargv, nargv);
}
sysfatal("exec: %r");
}
for(p = args; *p; p++)
free(*p);
}
exits(nil);
}