busybox/findutils/xargs.c
Eric Andersen 8876fb2f59 last_patch89 from vodz:
Manuel,

    I rewrite bb_getopt_ulflags() function for more universal usage.
    My version support now:
    - options with arguments (optional arg as GNU extension also)
    - complementaly and/or incomplementaly and/or incongruously and/or list
    options
    - long_opt (all applets may have long option, add supporting is trivial)
    This realisation full compatibile from your version.
    Code size grow 480 bytes, but only coreutils/* over compensate this size
    after using new function. Last patch reduced over 800 bytes and not full
    applied to all. "mkdir" and "mv" applets have long_opt now for demonstrate
    trivial addition support long_opt with usage new bb_getopt_ulflags().
    Complementaly and/or incomplementaly and/or incongruously and/or list options
    logic is not trivial, but new "cut" and "grep" applets using this logic
    for examples with full demostrating. New "grep" applet reduced over 300
    bytes.

    Mark,
    Also. I removed bug from "grep" applet.
    $ echo a b | busybox grep -e a b
    a b
    a b
    But right is printing one only.

    --w
    vodz
2003-06-20 09:01:58 +00:00

116 lines
2.9 KiB
C

/*
* Mini xargs implementation for busybox
* Only "-prt" options are supported in this version of xargs.
*
* (C) 2002 by Vladimir Oleynik <dzo@simtreas.ru>
*
* Special thanks Mark Whitley for stimul to rewrote :)
*
* 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; either version 2 of the License, or
* (at your option) any later version.
*
* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <getopt.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/wait.h>
#include "busybox.h"
/*
This function have special algorithm.
Don`t use fork and include to main!
*/
static void xargs_exec(char * const * args)
{
int p;
int common[4]; /* shared vfork stack */
common[0] = 0;
if ((p = vfork()) >= 0) {
if (p == 0) {
/* vfork -- child */
execvp(args[0], args);
common[0] = errno; /* set error to shared stack */
_exit(1);
} else {
/* vfork -- parent */
wait(NULL);
if(common[0]) {
errno = common[0];
bb_perror_msg_and_die("%s", args[0]);
}
}
} else {
bb_perror_msg_and_die("vfork");
}
}
int xargs_main(int argc, char **argv)
{
char *file_to_act_on;
char **args;
int i, a;
char flg_vi; /* verbose |& interactive */
char flg_no_empty;
bb_opt_complementaly = "pt";
a = bb_getopt_ulflags(argc, argv, "tpr");
flg_vi = a & 3;
flg_no_empty = a & 4;
a = argc - optind;
argv += optind;
if(a==0) {
/* default behavior is to echo all the filenames */
*argv = "/bin/echo";
a++;
}
/* allocating pointers for execvp: a*arg, arg from stdin, NULL */
args = xcalloc(a + 3, sizeof(char *));
/* Store the command to be executed (taken from the command line) */
for (i = 0; i < a; i++)
args[i] = *argv++;
/* Now, read in one line at a time from stdin, and store this
* line to be used later as an argument to the command */
while ((file_to_act_on = bb_get_chomped_line_from_file(stdin)) != NULL) {
if(file_to_act_on[0] != 0 || flg_no_empty == 0) {
args[a] = file_to_act_on[0] ? file_to_act_on : NULL;
if(flg_vi) {
for(i=0; args[i]; i++) {
if(i)
fputc(' ', stderr);
fputs(args[i], stderr);
}
fputs(((flg_vi & 2) ? " ?..." : "\n"), stderr);
}
if((flg_vi & 2) == 0 || bb_ask_confirmation() != 0 ) {
xargs_exec(args);
}
}
/* clean up */
free(file_to_act_on);
}
#ifdef CONFIG_FEATURE_CLEAN_UP
free(args);
#endif
return 0;
}