1/* Serial interface for a pipe to a separate program 2 Copyright (C) 1999, 2000, 2001, 2007 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 36static int pipe_open (struct serial *scb, const char *name); 37static void pipe_close (struct serial *scb); 38 39extern void _initialize_ser_pipe (void); 40 41struct pipe_state 42 { 43 int pid; 44 }; 45 46/* Open up a raw pipe */ 47 48static int 49pipe_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 138static void 139pipe_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 154static struct serial_ops pipe_ops; 155 156void 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} 183