ladybird/Userland/kill.cpp
Andreas Kling a6b2598fba Userland: Teach "kill" to understand signal names (not just numbers)
You can now do things like "kill -STOP pid" :^)

The getsignalbyname() helper function should probably move to LibC
or somewhere where it can be used by other signal related programs.
2020-10-29 11:45:53 +01:00

135 lines
3.5 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
* All rights reserved.
*
* 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 COPYRIGHT HOLDERS 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 COPYRIGHT HOLDER 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 <AK/Optional.h>
#include <AK/String.h>
#include <ctype.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
static void print_usage_and_exit()
{
printf("usage: kill [-signal] <PID>\n");
exit(1);
}
static const char* signal_names[] = {
"INVAL",
"HUP",
"INT",
"QUIT",
"ILL",
"TRAP",
"ABRT",
"BUS",
"FPE",
"KILL",
"USR1",
"SEGV",
"USR2",
"PIPE",
"ALRM",
"TERM",
"STKFLT",
"CHLD",
"CONT",
"STOP",
"TSTP",
"TTIN",
"TTOU",
"URG",
"XCPU",
"XFSZ",
"VTALRM",
"PROF",
"WINCH",
"IO",
"INFO",
"SYS"
};
static_assert(sizeof(signal_names) == sizeof(const char*) * 32);
int getsignalbyname(const char* name)
{
ASSERT(name);
for (size_t i = 0; i < NSIG; ++i) {
auto* signal_name = signal_names[i];
if (!strcmp(signal_name, name))
return i;
}
errno = EINVAL;
return -1;
}
int main(int argc, char** argv)
{
if (pledge("stdio proc", nullptr) < 0) {
perror("pledge");
return 1;
}
if (argc != 2 && argc != 3)
print_usage_and_exit();
unsigned signum = SIGTERM;
int pid_argi = 1;
if (argc == 3) {
pid_argi = 2;
if (argv[1][0] != '-')
print_usage_and_exit();
Optional<unsigned> number;
if (isalpha(argv[1][1])) {
int value = getsignalbyname(&argv[1][1]);
if (value >= 0 && value < NSIG)
number = value;
}
if (!number.has_value())
number = StringView(&argv[1][1]).to_uint();
if (!number.has_value()) {
printf("'%s' is not a valid signal name or number\n", &argv[1][1]);
return 2;
}
signum = number.value();
}
auto pid_opt = String(argv[pid_argi]).to_int();
if (!pid_opt.has_value()) {
printf("'%s' is not a valid PID\n", argv[pid_argi]);
return 3;
}
pid_t pid = pid_opt.value();
int rc = kill(pid, signum);
if (rc < 0)
perror("kill");
return 0;
}