Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2002 Jeff Dike (jdike@karaya.com) |
| 3 | * Licensed under the GPL |
| 4 | */ |
| 5 | |
| 6 | #include <stdio.h> |
| 7 | #include <unistd.h> |
| 8 | #include <errno.h> |
| 9 | #include "user_util.h" |
| 10 | #include "user.h" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 11 | #include "mconsole.h" |
| 12 | #include "os.h" |
| 13 | #include "choose-mode.h" |
| 14 | #include "mode.h" |
| 15 | |
| 16 | struct dog_data { |
| 17 | int stdin; |
| 18 | int stdout; |
| 19 | int close_me[2]; |
| 20 | }; |
| 21 | |
| 22 | static void pre_exec(void *d) |
| 23 | { |
| 24 | struct dog_data *data = d; |
| 25 | |
| 26 | dup2(data->stdin, 0); |
| 27 | dup2(data->stdout, 1); |
| 28 | dup2(data->stdout, 2); |
| 29 | os_close_file(data->stdin); |
| 30 | os_close_file(data->stdout); |
| 31 | os_close_file(data->close_me[0]); |
| 32 | os_close_file(data->close_me[1]); |
| 33 | } |
| 34 | |
| 35 | int start_watchdog(int *in_fd_ret, int *out_fd_ret, char *sock) |
| 36 | { |
| 37 | struct dog_data data; |
| 38 | int in_fds[2], out_fds[2], pid, n, err; |
| 39 | char pid_buf[sizeof("nnnnn\0")], c; |
| 40 | char *pid_args[] = { "/usr/bin/uml_watchdog", "-pid", pid_buf, NULL }; |
| 41 | char *mconsole_args[] = { "/usr/bin/uml_watchdog", "-mconsole", NULL, |
| 42 | NULL }; |
| 43 | char **args = NULL; |
| 44 | |
| 45 | err = os_pipe(in_fds, 1, 0); |
| 46 | if(err < 0){ |
| 47 | printk("harddog_open - os_pipe failed, err = %d\n", -err); |
| 48 | goto out; |
| 49 | } |
| 50 | |
| 51 | err = os_pipe(out_fds, 1, 0); |
| 52 | if(err < 0){ |
| 53 | printk("harddog_open - os_pipe failed, err = %d\n", -err); |
| 54 | goto out_close_in; |
| 55 | } |
| 56 | |
| 57 | data.stdin = out_fds[0]; |
| 58 | data.stdout = in_fds[1]; |
| 59 | data.close_me[0] = out_fds[1]; |
| 60 | data.close_me[1] = in_fds[0]; |
| 61 | |
| 62 | if(sock != NULL){ |
| 63 | mconsole_args[2] = sock; |
| 64 | args = mconsole_args; |
| 65 | } |
| 66 | else { |
| 67 | /* XXX The os_getpid() is not SMP correct */ |
| 68 | sprintf(pid_buf, "%d", CHOOSE_MODE(tracing_pid, os_getpid())); |
| 69 | args = pid_args; |
| 70 | } |
| 71 | |
| 72 | pid = run_helper(pre_exec, &data, args, NULL); |
| 73 | |
| 74 | os_close_file(out_fds[0]); |
| 75 | os_close_file(in_fds[1]); |
| 76 | |
| 77 | if(pid < 0){ |
| 78 | err = -pid; |
| 79 | printk("harddog_open - run_helper failed, errno = %d\n", -err); |
| 80 | goto out_close_out; |
| 81 | } |
| 82 | |
| 83 | n = os_read_file(in_fds[0], &c, sizeof(c)); |
| 84 | if(n == 0){ |
| 85 | printk("harddog_open - EOF on watchdog pipe\n"); |
| 86 | helper_wait(pid); |
| 87 | err = -EIO; |
| 88 | goto out_close_out; |
| 89 | } |
| 90 | else if(n < 0){ |
| 91 | printk("harddog_open - read of watchdog pipe failed, " |
| 92 | "err = %d\n", -n); |
| 93 | helper_wait(pid); |
| 94 | err = n; |
| 95 | goto out_close_out; |
| 96 | } |
| 97 | *in_fd_ret = in_fds[0]; |
| 98 | *out_fd_ret = out_fds[1]; |
| 99 | return(0); |
| 100 | |
| 101 | out_close_in: |
| 102 | os_close_file(in_fds[0]); |
| 103 | os_close_file(in_fds[1]); |
| 104 | out_close_out: |
| 105 | os_close_file(out_fds[0]); |
| 106 | os_close_file(out_fds[1]); |
| 107 | out: |
| 108 | return(err); |
| 109 | } |
| 110 | |
| 111 | void stop_watchdog(int in_fd, int out_fd) |
| 112 | { |
| 113 | os_close_file(in_fd); |
| 114 | os_close_file(out_fd); |
| 115 | } |
| 116 | |
| 117 | int ping_watchdog(int fd) |
| 118 | { |
| 119 | int n; |
| 120 | char c = '\n'; |
| 121 | |
| 122 | n = os_write_file(fd, &c, sizeof(c)); |
| 123 | if(n != sizeof(c)){ |
| 124 | printk("ping_watchdog - write failed, err = %d\n", -n); |
| 125 | if(n < 0) |
| 126 | return(n); |
| 127 | return(-EIO); |
| 128 | } |
| 129 | return 1; |
| 130 | |
| 131 | } |
| 132 | |
| 133 | /* |
| 134 | * Overrides for Emacs so that we follow Linus's tabbing style. |
| 135 | * Emacs will notice this stuff at the end of the file and automatically |
| 136 | * adjust the settings for this buffer only. This must remain at the end |
| 137 | * of the file. |
| 138 | * --------------------------------------------------------------------------- |
| 139 | * Local variables: |
| 140 | * c-file-style: "linux" |
| 141 | * End: |
| 142 | */ |