mirror of
https://github.com/freebsd/freebsd-src
synced 2024-10-07 09:00:28 +00:00
3610bffd28
Right now pkill/pgrep cut off at _POSIX2_LINE_MAX (2048), but argument strings can be much larger (ARG_MAX is 256K/512K). Stop arbitrarily cutting the search off at 2K, rather than documenting the limit. Reviewed by: allanjude (earlier version), des Sponsored by: Klara, Inc. Differential Revision: https://reviews.freebsd.org/D38663
124 lines
3.2 KiB
C
124 lines
3.2 KiB
C
/*-
|
|
* SPDX-License-Identifier: BSD-2-Clause
|
|
*
|
|
* Copyright (c) 2023 Klara, Inc.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*/
|
|
#include <sys/cdefs.h>
|
|
|
|
#include <err.h>
|
|
#include <errno.h>
|
|
#include <fcntl.h>
|
|
#include <limits.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <stdio.h>
|
|
#include <unistd.h>
|
|
|
|
static int
|
|
exec_shortargs(char *argv[])
|
|
{
|
|
char *flag_arg = argv[2];
|
|
char *sentinel = argv[3];
|
|
char * nargv[] = { argv[0], __DECONST(char *, "--spin"), flag_arg,
|
|
sentinel, NULL };
|
|
char * const nenvp[] = { NULL };
|
|
|
|
execve(argv[0], nargv, nenvp);
|
|
err(1, "execve");
|
|
}
|
|
|
|
static int
|
|
exec_largeargs(char *argv[])
|
|
{
|
|
char *flag_arg = argv[2];
|
|
char *sentinel = argv[3];
|
|
/*
|
|
* Account for each argument and their NUL terminator, as well as an
|
|
* extra NUL terminator.
|
|
*/
|
|
size_t bufsz = ARG_MAX -
|
|
((strlen(argv[0]) + 1) + sizeof("--spin") + (strlen(flag_arg) + 1) +
|
|
(strlen(sentinel) + 1) + 1);
|
|
char *s = NULL;
|
|
char * nargv[] = { argv[0], __DECONST(char *, "--spin"), flag_arg, NULL,
|
|
sentinel, NULL };
|
|
char * const nenvp[] = { NULL };
|
|
|
|
/*
|
|
* Our heuristic may or may not be accurate, we'll keep trying with
|
|
* smaller argument sizes as needed until we stop getting E2BIG.
|
|
*/
|
|
do {
|
|
if (s == NULL)
|
|
s = malloc(bufsz + 1);
|
|
else
|
|
s = realloc(s, bufsz + 1);
|
|
if (s == NULL)
|
|
abort();
|
|
memset(s, 'x', bufsz);
|
|
s[bufsz] = '\0';
|
|
nargv[3] = s;
|
|
|
|
execve(argv[0], nargv, nenvp);
|
|
bufsz--;
|
|
} while (errno == E2BIG);
|
|
err(1, "execve");
|
|
}
|
|
|
|
int
|
|
main(int argc, char *argv[])
|
|
{
|
|
|
|
if (argc > 1 && strcmp(argv[1], "--spin") == 0) {
|
|
int fd;
|
|
|
|
if (argc < 4) {
|
|
fprintf(stderr, "usage: %s --spin flagfile ...\n", argv[0]);
|
|
return (1);
|
|
}
|
|
|
|
fd = open(argv[2], O_RDWR | O_CREAT, 0755);
|
|
if (fd < 0)
|
|
err(1, "%s", argv[2]);
|
|
close(fd);
|
|
|
|
for (;;) {
|
|
sleep(1);
|
|
}
|
|
|
|
return (1);
|
|
}
|
|
|
|
if (argc != 4) {
|
|
fprintf(stderr, "usage: %s [--short | --long] flagfile sentinel\n",
|
|
argv[0]);
|
|
return (1);
|
|
}
|
|
|
|
if (strcmp(argv[1], "--short") == 0)
|
|
exec_shortargs(argv);
|
|
else
|
|
exec_largeargs(argv);
|
|
}
|