openssh-portable/contrib/win32/win32compat/signal_sigchld.c

233 lines
6.4 KiB
C

/*
* Author: Manoj Ampalam <manoj.ampalam@microsoft.com>
*
* Copyright(c) 2015 Microsoft Corp.
* All rights reserved
*
* Helper routines to support SIGCLD and related routines implementation
*
* 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 ``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 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 "signal_internal.h"
struct _children children;
int
sw_add_child(HANDLE child, DWORD pid) {
DWORD first_zombie_index;
debug("Register child %p pid %d, %d zombies of %d", child, pid,
children.num_zombies, children.num_children);
if (children.num_children == MAX_CHILDREN) {
errno = ENOMEM;
return -1;
}
if (children.num_zombies) {
first_zombie_index = children.num_children - children.num_zombies;
children.handles[children.num_children] = children.handles[first_zombie_index];
children.process_id[children.num_children] = children.process_id[first_zombie_index];
children.handles[first_zombie_index] = child;
children.process_id[first_zombie_index] = pid;
}
else {
children.handles[children.num_children] = child;
children.process_id[children.num_children] = pid;
}
children.num_children++;
return 0;
}
int
sw_remove_child_at_index(DWORD index) {
DWORD last_non_zombie;
debug("Unregister child at index %d, %d zombies of %d", index,
children.num_zombies, children.num_children);
if ((index >= children.num_children)
|| (children.num_children == 0)) {
errno = EINVAL;
return -1;
}
CloseHandle(children.handles[index]);
if (children.num_zombies == 0) {
children.handles[index] = children.handles[children.num_children - 1];
children.process_id[index] = children.process_id[children.num_children - 1];
}
else {
/* if its a zombie */
if (index >= (children.num_children - children.num_zombies)) {
children.handles[index] = children.handles[children.num_children - 1];
children.process_id[index] = children.process_id[children.num_children - 1];
children.num_zombies--;
}
else {
last_non_zombie = children.num_children - children.num_zombies - 1;
children.handles[index] = children.handles[last_non_zombie];
children.process_id[index] = children.process_id[last_non_zombie];
children.handles[last_non_zombie] = children.handles[children.num_children - 1];
children.process_id[last_non_zombie] = children.process_id[children.num_children - 1];
}
}
children.num_children--;
return 0;
}
int
sw_child_to_zombie(DWORD index) {
DWORD last_non_zombie, last_child, zombie_pid;
HANDLE zombie_handle;
debug("zombie'ing child at index %d, %d zombies of %d", index,
children.num_zombies, children.num_children);
if (index >= children.num_children) {
errno = EINVAL;
return -1;
}
zombie_pid = children.process_id[index];
zombie_handle = children.handles[index];
last_non_zombie = children.num_children - children.num_zombies - 1;
last_child = children.num_children - 1;
children.handles[index] = children.handles[last_non_zombie];
children.process_id[index] = children.process_id[last_non_zombie];
children.handles[last_non_zombie] = children.handles[index];
children.process_id[last_non_zombie] = children.process_id[index];
children.num_zombies++;
return 0;
}
int
sw_kill(int pid, int sig) {
int child_index, i;
if (pid == GetCurrentProcessId())
return sw_raise(sig);
/* for child processes - only SIGTERM supported*/
child_index = -1;
for (i = 0; i < children.num_children; i++)
if (children.process_id[i] == pid) {
child_index = i;
break;
}
if (child_index != -1)
TerminateProcess(children.handles[child_index], 0);
return 0;
}
int waitpid(int pid, int *status, int options) {
DWORD index, ret, ret_id, exit_code, timeout = 0;
HANDLE process = NULL;
debug3("waitpid - pid:%d, options:%d", pid, options);
if (options & (~WNOHANG)) {
errno = ENOTSUP;
DebugBreak();
return -1;
}
if ((pid < -1) || (pid == 0)) {
errno = ENOTSUP;
DebugBreak();
return -1;
}
if (children.num_children == 0) {
errno = ECHILD;
return -1;
}
if (pid > 0) {
if (options != 0) {
errno = ENOTSUP;
DebugBreak();
return -1;
}
/* find entry in table */
for (index = 0; index < children.num_children; index++)
if (children.process_id[index] == pid)
break;
if (index == children.num_children) {
errno = ECHILD;
return -1;
}
process = children.handles[index];
ret = WaitForSingleObject(process, INFINITE);
if (ret != WAIT_OBJECT_0)
DebugBreak();//fatal
ret_id = children.process_id[index];
GetExitCodeProcess(process, &exit_code);
/* process handle will be closed when its removed from list */
sw_remove_child_at_index(index);
if (status)
*status = exit_code;
return ret_id;
}
/* pid = -1*/
timeout = INFINITE;
if (options & WNOHANG)
timeout = 0;
ret = WaitForMultipleObjects(children.num_children, children.handles, FALSE, timeout);
if ((ret >= WAIT_OBJECT_0) && (ret < (WAIT_OBJECT_0 + children.num_children))) {
index = ret - WAIT_OBJECT_0;
process = children.handles[index];
ret_id = children.process_id[index];
GetExitCodeProcess(process, &exit_code);
/* process handle will be closed when its removed from list */
sw_remove_child_at_index(index);
if (status)
*status = exit_code;
return ret_id;
}
else if (ret == WAIT_TIMEOUT) {
/* TODO - assert that WNOHANG was specified*/
return 0;
}
DebugBreak();//fatal
return -1;
}
void
sw_cleanup_child_zombies() {
int pid = 1;
while (pid > 0) {
pid = waitpid(-1, NULL, WNOHANG);
}
}