1/* Serial interface for a pipe to a separate program 2 Copyright (C) 1999, 2000, 2001, 2007, 2008, 2009, 2010, 2011 3 Free Software Foundation, Inc. 4 5 Contributed by Cygnus Solutions. 6 7 This file is part of GDB. 8 9 This program is free software; you can redistribute it and/or modify 10 it under the terms of the GNU General Public License as published by 11 the Free Software Foundation; either version 3 of the License, or 12 (at your option) any later version. 13 14 This program is distributed in the hope that it will be useful, 15 but WITHOUT ANY WARRANTY; without even the implied warranty of 16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 GNU General Public License for more details. 18 19 You should have received a copy of the GNU General Public License 20 along with this program. If not, see <http://www.gnu.org/licenses/>. */ 21 22#include "defs.h" 23#include "serial.h" 24#include "ser-base.h" 25#include "ser-unix.h" 26 27#include "gdb_vfork.h" 28 29#include <sys/types.h> 30#include <sys/socket.h> 31#include <sys/time.h> 32#include <fcntl.h> 33#include "gdb_string.h" 34#include "gdb_wait.h" 35 36#include <signal.h> 37 38static int pipe_open (struct serial *scb, const char *name); 39static void pipe_close (struct serial *scb); 40 41extern void _initialize_ser_pipe (void); 42 43struct pipe_state 44 { 45 int pid; 46 }; 47 48/* Open up a raw pipe. */ 49 50static int 51pipe_open (struct serial *scb, const char *name) 52{ 53#if !HAVE_SOCKETPAIR 54 return -1; 55#else 56 struct pipe_state *state; 57 /* This chunk: */ 58 /* Copyright (c) 1988, 1993 59 * The Regents of the University of California. All rights reserved. 60 * 61 * This code is derived from software written by Ken Arnold and 62 * published in UNIX Review, Vol. 6, No. 8. 63 */ 64 int pdes[2]; 65 int err_pdes[2]; 66 int pid; 67 68 if (socketpair (AF_UNIX, SOCK_STREAM, 0, pdes) < 0) 69 return -1; 70 if (socketpair (AF_UNIX, SOCK_STREAM, 0, err_pdes) < 0) 71 { 72 close (pdes[0]); 73 close (pdes[1]); 74 return -1; 75 } 76 77 /* Create the child process to run the command in. Note that the 78 apparent call to vfork() below *might* actually be a call to 79 fork() due to the fact that autoconf will ``#define vfork fork'' 80 on certain platforms. */ 81 pid = vfork (); 82 83 /* Error. */ 84 if (pid == -1) 85 { 86 close (pdes[0]); 87 close (pdes[1]); 88 close (err_pdes[0]); 89 close (err_pdes[1]); 90 return -1; 91 } 92 93 if (fcntl (err_pdes[0], F_SETFL, O_NONBLOCK) == -1) 94 { 95 close (err_pdes[0]); 96 close (err_pdes[1]); 97 err_pdes[0] = err_pdes[1] = -1; 98 } 99 100 /* Child. */ 101 if (pid == 0) 102 { 103 /* We don't want ^c to kill the connection. */ 104#ifdef HAVE_SETSID 105 pid_t sid = setsid (); 106 if (sid == -1) 107 signal (SIGINT, SIG_IGN); 108#else 109 signal (SIGINT, SIG_IGN); 110#endif 111 112 /* Re-wire pdes[1] to stdin/stdout. */ 113 close (pdes[0]); 114 if (pdes[1] != STDOUT_FILENO) 115 { 116 dup2 (pdes[1], STDOUT_FILENO); 117 close (pdes[1]); 118 } 119 dup2 (STDOUT_FILENO, STDIN_FILENO); 120 121 if (err_pdes[0] != -1) 122 { 123 close (err_pdes[0]); 124 dup2 (err_pdes[1], STDERR_FILENO); 125 close (err_pdes[1]); 126 } 127#if 0 128 /* close any stray FD's - FIXME - how? */ 129 /* POSIX.2 B.3.2.2 "popen() shall ensure that any streams 130 from previous popen() calls that remain open in the 131 parent process are closed in the new child process. */ 132 for (old = pidlist; old; old = old->next) 133 close (fileno (old->fp)); /* Don't allow a flush. */ 134#endif 135 execl ("/bin/sh", "sh", "-c", name, (char *) 0); 136 _exit (127); 137 } 138 139 /* Parent. */ 140 close (pdes[1]); 141 if (err_pdes[1] != -1) 142 close (err_pdes[1]); 143 /* :end chunk */ 144 state = XMALLOC (struct pipe_state); 145 state->pid = pid; 146 scb->fd = pdes[0]; 147 scb->error_fd = err_pdes[0]; 148 scb->state = state; 149 150 /* If we don't do this, GDB simply exits when the remote side dies. */ 151 signal (SIGPIPE, SIG_IGN); 152 return 0; 153#endif 154} 155 156static void 157pipe_close (struct serial *scb) 158{ 159 struct pipe_state *state = scb->state; 160 161 close (scb->fd); 162 scb->fd = -1; 163 164 if (state != NULL) 165 { 166 int status; 167 kill (state->pid, SIGTERM); 168#ifdef HAVE_WAITPID 169 /* Assume the program will exit after SIGTERM. Might be 170 useful to print any remaining stderr output from 171 scb->error_fd while waiting. */ 172 waitpid (state->pid, &status, 0); 173#endif 174 if (scb->error_fd != -1) 175 close (scb->error_fd); 176 scb->error_fd = -1; 177 xfree (state); 178 scb->state = NULL; 179 } 180} 181 182int 183gdb_pipe (int pdes[2]) 184{ 185#if !HAVE_SOCKETPAIR 186 errno = ENOSYS; 187 return -1; 188#else 189 190 if (socketpair (AF_UNIX, SOCK_STREAM, 0, pdes) < 0) 191 return -1; 192 193 /* If we don't do this, GDB simply exits when the remote side 194 dies. */ 195 signal (SIGPIPE, SIG_IGN); 196 return 0; 197#endif 198} 199 200void 201_initialize_ser_pipe (void) 202{ 203 struct serial_ops *ops = XMALLOC (struct serial_ops); 204 205 memset (ops, 0, sizeof (struct serial_ops)); 206 ops->name = "pipe"; 207 ops->next = 0; 208 ops->open = pipe_open; 209 ops->close = pipe_close; 210 ops->readchar = ser_base_readchar; 211 ops->write = ser_base_write; 212 ops->flush_output = ser_base_flush_output; 213 ops->flush_input = ser_base_flush_input; 214 ops->send_break = ser_base_send_break; 215 ops->go_raw = ser_base_raw; 216 ops->get_tty_state = ser_base_get_tty_state; 217 ops->copy_tty_state = ser_base_copy_tty_state; 218 ops->set_tty_state = ser_base_set_tty_state; 219 ops->print_tty_state = ser_base_print_tty_state; 220 ops->noflush_set_tty_state = ser_base_noflush_set_tty_state; 221 ops->setbaudrate = ser_base_setbaudrate; 222 ops->setstopbits = ser_base_setstopbits; 223 ops->drain_output = ser_base_drain_output; 224 ops->async = ser_base_async; 225 ops->read_prim = ser_unix_read_prim; 226 ops->write_prim = ser_unix_write_prim; 227 serial_add_interface (ops); 228} 229