| 1 | /* Serial interface for a pipe to a separate program |
| 2 | Copyright (C) 1999, 2000, 2001, 2007, 2008 Free Software Foundation, Inc. |
| 3 | |
| 4 | Contributed by Cygnus Solutions. |
| 5 | |
| 6 | This file is part of GDB. |
| 7 | |
| 8 | This program is free software; you can redistribute it and/or modify |
| 9 | it under the terms of the GNU General Public License as published by |
| 10 | the Free Software Foundation; either version 3 of the License, or |
| 11 | (at your option) any later version. |
| 12 | |
| 13 | This program is distributed in the hope that it will be useful, |
| 14 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 16 | GNU General Public License for more details. |
| 17 | |
| 18 | You should have received a copy of the GNU General Public License |
| 19 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 20 | |
| 21 | #include "defs.h" |
| 22 | #include "serial.h" |
| 23 | #include "ser-base.h" |
| 24 | #include "ser-unix.h" |
| 25 | |
| 26 | #include "gdb_vfork.h" |
| 27 | |
| 28 | #include <sys/types.h> |
| 29 | #include <sys/socket.h> |
| 30 | #include <sys/time.h> |
| 31 | #include <fcntl.h> |
| 32 | #include "gdb_string.h" |
| 33 | |
| 34 | #include <signal.h> |
| 35 | |
| 36 | static int pipe_open (struct serial *scb, const char *name); |
| 37 | static void pipe_close (struct serial *scb); |
| 38 | |
| 39 | extern void _initialize_ser_pipe (void); |
| 40 | |
| 41 | struct pipe_state |
| 42 | { |
| 43 | int pid; |
| 44 | }; |
| 45 | |
| 46 | /* Open up a raw pipe */ |
| 47 | |
| 48 | static int |
| 49 | pipe_open (struct serial *scb, const char *name) |
| 50 | { |
| 51 | #if !HAVE_SOCKETPAIR |
| 52 | return -1; |
| 53 | #else |
| 54 | struct pipe_state *state; |
| 55 | /* This chunk: */ |
| 56 | /* Copyright (c) 1988, 1993 |
| 57 | * The Regents of the University of California. All rights reserved. |
| 58 | * |
| 59 | * This code is derived from software written by Ken Arnold and |
| 60 | * published in UNIX Review, Vol. 6, No. 8. |
| 61 | */ |
| 62 | int pdes[2]; |
| 63 | int err_pdes[2]; |
| 64 | int pid; |
| 65 | if (socketpair (AF_UNIX, SOCK_STREAM, 0, pdes) < 0) |
| 66 | return -1; |
| 67 | if (socketpair (AF_UNIX, SOCK_STREAM, 0, err_pdes) < 0) |
| 68 | return -1; |
| 69 | |
| 70 | /* Create the child process to run the command in. Note that the |
| 71 | apparent call to vfork() below *might* actually be a call to |
| 72 | fork() due to the fact that autoconf will ``#define vfork fork'' |
| 73 | on certain platforms. */ |
| 74 | pid = vfork (); |
| 75 | |
| 76 | /* Error. */ |
| 77 | if (pid == -1) |
| 78 | { |
| 79 | close (pdes[0]); |
| 80 | close (pdes[1]); |
| 81 | close (err_pdes[0]); |
| 82 | close (err_pdes[1]); |
| 83 | return -1; |
| 84 | } |
| 85 | |
| 86 | if (fcntl (err_pdes[0], F_SETFL, O_NONBLOCK) == -1) |
| 87 | { |
| 88 | close (err_pdes[0]); |
| 89 | close (err_pdes[1]); |
| 90 | err_pdes[0] = err_pdes[1] = -1; |
| 91 | } |
| 92 | |
| 93 | /* Child. */ |
| 94 | if (pid == 0) |
| 95 | { |
| 96 | /* re-wire pdes[1] to stdin/stdout */ |
| 97 | close (pdes[0]); |
| 98 | if (pdes[1] != STDOUT_FILENO) |
| 99 | { |
| 100 | dup2 (pdes[1], STDOUT_FILENO); |
| 101 | close (pdes[1]); |
| 102 | } |
| 103 | dup2 (STDOUT_FILENO, STDIN_FILENO); |
| 104 | |
| 105 | if (err_pdes[0] != -1) |
| 106 | { |
| 107 | close (err_pdes[0]); |
| 108 | dup2 (err_pdes[1], STDERR_FILENO); |
| 109 | close (err_pdes[1]); |
| 110 | } |
| 111 | #if 0 |
| 112 | /* close any stray FD's - FIXME - how? */ |
| 113 | /* POSIX.2 B.3.2.2 "popen() shall ensure that any streams |
| 114 | from previous popen() calls that remain open in the |
| 115 | parent process are closed in the new child process. */ |
| 116 | for (old = pidlist; old; old = old->next) |
| 117 | close (fileno (old->fp)); /* don't allow a flush */ |
| 118 | #endif |
| 119 | execl ("/bin/sh", "sh", "-c", name, (char *) 0); |
| 120 | _exit (127); |
| 121 | } |
| 122 | |
| 123 | /* Parent. */ |
| 124 | close (pdes[1]); |
| 125 | /* :end chunk */ |
| 126 | state = XMALLOC (struct pipe_state); |
| 127 | state->pid = pid; |
| 128 | scb->fd = pdes[0]; |
| 129 | scb->error_fd = err_pdes[0]; |
| 130 | scb->state = state; |
| 131 | |
| 132 | /* If we don't do this, GDB simply exits when the remote side dies. */ |
| 133 | signal (SIGPIPE, SIG_IGN); |
| 134 | return 0; |
| 135 | #endif |
| 136 | } |
| 137 | |
| 138 | static void |
| 139 | pipe_close (struct serial *scb) |
| 140 | { |
| 141 | struct pipe_state *state = scb->state; |
| 142 | if (state != NULL) |
| 143 | { |
| 144 | int pid = state->pid; |
| 145 | close (scb->fd); |
| 146 | scb->fd = -1; |
| 147 | xfree (state); |
| 148 | scb->state = NULL; |
| 149 | kill (pid, SIGTERM); |
| 150 | /* Might be useful to check that the child does die. */ |
| 151 | } |
| 152 | } |
| 153 | |
| 154 | static struct serial_ops pipe_ops; |
| 155 | |
| 156 | void |
| 157 | _initialize_ser_pipe (void) |
| 158 | { |
| 159 | struct serial_ops *ops = XMALLOC (struct serial_ops); |
| 160 | memset (ops, 0, sizeof (struct serial_ops)); |
| 161 | ops->name = "pipe"; |
| 162 | ops->next = 0; |
| 163 | ops->open = pipe_open; |
| 164 | ops->close = pipe_close; |
| 165 | ops->readchar = ser_base_readchar; |
| 166 | ops->write = ser_base_write; |
| 167 | ops->flush_output = ser_base_flush_output; |
| 168 | ops->flush_input = ser_base_flush_input; |
| 169 | ops->send_break = ser_base_send_break; |
| 170 | ops->go_raw = ser_base_raw; |
| 171 | ops->get_tty_state = ser_base_get_tty_state; |
| 172 | ops->set_tty_state = ser_base_set_tty_state; |
| 173 | ops->print_tty_state = ser_base_print_tty_state; |
| 174 | ops->noflush_set_tty_state = ser_base_noflush_set_tty_state; |
| 175 | ops->setbaudrate = ser_base_setbaudrate; |
| 176 | ops->setstopbits = ser_base_setstopbits; |
| 177 | ops->drain_output = ser_base_drain_output; |
| 178 | ops->async = ser_base_async; |
| 179 | ops->read_prim = ser_unix_read_prim; |
| 180 | ops->write_prim = ser_unix_write_prim; |
| 181 | serial_add_interface (ops); |
| 182 | } |