1/*
  2 * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
  3 * Licensed under the GPL
  4 */
  5
  6#include <stdio.h>
  7#include <unistd.h>
  8#include <errno.h>
  9#include "os.h"
 
 10
 11struct dog_data {
 12	int stdin;
 13	int stdout;
 14	int close_me[2];
 15};
 16
 17static void pre_exec(void *d)
 18{
 19	struct dog_data *data = d;
 20
 21	dup2(data->stdin, 0);
 22	dup2(data->stdout, 1);
 23	dup2(data->stdout, 2);
 24	close(data->stdin);
 25	close(data->stdout);
 26	close(data->close_me[0]);
 27	close(data->close_me[1]);
 28}
 29
 30int start_watchdog(int *in_fd_ret, int *out_fd_ret, char *sock)
 31{
 32	struct dog_data data;
 33	int in_fds[2], out_fds[2], pid, n, err;
 34	char pid_buf[sizeof("nnnnnnn\0")], c;
 35	char *pid_args[] = { "/usr/bin/uml_watchdog", "-pid", pid_buf, NULL };
 36	char *mconsole_args[] = { "/usr/bin/uml_watchdog", "-mconsole", NULL,
 37				  NULL };
 38	char **args = NULL;
 39
 40	err = os_pipe(in_fds, 1, 0);
 41	if (err < 0) {
 42		printk("harddog_open - os_pipe failed, err = %d\n", -err);
 43		goto out;
 44	}
 45
 46	err = os_pipe(out_fds, 1, 0);
 47	if (err < 0) {
 48		printk("harddog_open - os_pipe failed, err = %d\n", -err);
 49		goto out_close_in;
 50	}
 51
 52	data.stdin = out_fds[0];
 53	data.stdout = in_fds[1];
 54	data.close_me[0] = out_fds[1];
 55	data.close_me[1] = in_fds[0];
 56
 57	if (sock != NULL) {
 58		mconsole_args[2] = sock;
 59		args = mconsole_args;
 60	}
 61	else {
 62		/* XXX The os_getpid() is not SMP correct */
 63		sprintf(pid_buf, "%d", os_getpid());
 64		args = pid_args;
 65	}
 66
 67	pid = run_helper(pre_exec, &data, args);
 68
 69	close(out_fds[0]);
 70	close(in_fds[1]);
 71
 72	if (pid < 0) {
 73		err = -pid;
 74		printk("harddog_open - run_helper failed, errno = %d\n", -err);
 75		goto out_close_out;
 76	}
 77
 78	n = read(in_fds[0], &c, sizeof(c));
 79	if (n == 0) {
 80		printk("harddog_open - EOF on watchdog pipe\n");
 81		helper_wait(pid);
 82		err = -EIO;
 83		goto out_close_out;
 84	}
 85	else if (n < 0) {
 86		printk("harddog_open - read of watchdog pipe failed, "
 87		       "err = %d\n", errno);
 88		helper_wait(pid);
 89		err = n;
 90		goto out_close_out;
 91	}
 92	*in_fd_ret = in_fds[0];
 93	*out_fd_ret = out_fds[1];
 94	return 0;
 95
 96 out_close_in:
 97	close(in_fds[0]);
 98	close(in_fds[1]);
 99 out_close_out:
100	close(out_fds[0]);
101	close(out_fds[1]);
102 out:
103	return err;
104}
105
106void stop_watchdog(int in_fd, int out_fd)
107{
108	close(in_fd);
109	close(out_fd);
110}
111
112int ping_watchdog(int fd)
113{
114	int n;
115	char c = '\n';
116
117	n = write(fd, &c, sizeof(c));
118	if (n != sizeof(c)) {
119		printk("ping_watchdog - write failed, ret = %d, err = %d\n",
120		       n, errno);
121		if (n < 0)
122			return n;
123		return -EIO;
124	}
125	return 1;
126
127}

  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
 
  4 */
  5
  6#include <stdio.h>
  7#include <unistd.h>
  8#include <errno.h>
  9#include <os.h>
 10#include "harddog.h"
 11
 12struct dog_data {
 13	int stdin_fd;
 14	int stdout_fd;
 15	int close_me[2];
 16};
 17
 18static void pre_exec(void *d)
 19{
 20	struct dog_data *data = d;
 21
 22	dup2(data->stdin_fd, 0);
 23	dup2(data->stdout_fd, 1);
 24	dup2(data->stdout_fd, 2);
 25	close(data->stdin_fd);
 26	close(data->stdout_fd);
 27	close(data->close_me[0]);
 28	close(data->close_me[1]);
 29}
 30
 31int start_watchdog(int *in_fd_ret, int *out_fd_ret, char *sock)
 32{
 33	struct dog_data data;
 34	int in_fds[2], out_fds[2], pid, n, err;
 35	char pid_buf[sizeof("nnnnnnn\0")], c;
 36	char *pid_args[] = { "/usr/bin/uml_watchdog", "-pid", pid_buf, NULL };
 37	char *mconsole_args[] = { "/usr/bin/uml_watchdog", "-mconsole", NULL,
 38				  NULL };
 39	char **args = NULL;
 40
 41	err = os_pipe(in_fds, 1, 0);
 42	if (err < 0) {
 43		printk("harddog_open - os_pipe failed, err = %d\n", -err);
 44		goto out;
 45	}
 46
 47	err = os_pipe(out_fds, 1, 0);
 48	if (err < 0) {
 49		printk("harddog_open - os_pipe failed, err = %d\n", -err);
 50		goto out_close_in;
 51	}
 52
 53	data.stdin_fd = out_fds[0];
 54	data.stdout_fd = in_fds[1];
 55	data.close_me[0] = out_fds[1];
 56	data.close_me[1] = in_fds[0];
 57
 58	if (sock != NULL) {
 59		mconsole_args[2] = sock;
 60		args = mconsole_args;
 61	}
 62	else {
 63		/* XXX The os_getpid() is not SMP correct */
 64		sprintf(pid_buf, "%d", os_getpid());
 65		args = pid_args;
 66	}
 67
 68	pid = run_helper(pre_exec, &data, args);
 69
 70	close(out_fds[0]);
 71	close(in_fds[1]);
 72
 73	if (pid < 0) {
 74		err = -pid;
 75		printk("harddog_open - run_helper failed, errno = %d\n", -err);
 76		goto out_close_out;
 77	}
 78
 79	n = read(in_fds[0], &c, sizeof(c));
 80	if (n == 0) {
 81		printk("harddog_open - EOF on watchdog pipe\n");
 82		helper_wait(pid);
 83		err = -EIO;
 84		goto out_close_out;
 85	}
 86	else if (n < 0) {
 87		printk("harddog_open - read of watchdog pipe failed, "
 88		       "err = %d\n", errno);
 89		helper_wait(pid);
 90		err = n;
 91		goto out_close_out;
 92	}
 93	*in_fd_ret = in_fds[0];
 94	*out_fd_ret = out_fds[1];
 95	return 0;
 96
 97 out_close_in:
 98	close(in_fds[0]);
 99	close(in_fds[1]);
100 out_close_out:
101	close(out_fds[0]);
102	close(out_fds[1]);
103 out:
104	return err;
105}
106
107void stop_watchdog(int in_fd, int out_fd)
108{
109	close(in_fd);
110	close(out_fd);
111}
112
113int ping_watchdog(int fd)
114{
115	int n;
116	char c = '\n';
117
118	n = write(fd, &c, sizeof(c));
119	if (n != sizeof(c)) {
120		printk("ping_watchdog - write failed, ret = %d, err = %d\n",
121		       n, errno);
122		if (n < 0)
123			return n;
124		return -EIO;
125	}
126	return 1;
127
128}