1 /* Serial interface for a pipe to a separate program 2 Copyright (C) 1999, 2000, 2001, 2007, 2008, 2009 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 35 #include <signal.h> 36 37 static int pipe_open (struct serial *scb, const char *name); 38 static void pipe_close (struct serial *scb); 39 40 extern void _initialize_ser_pipe (void); 41 42 struct pipe_state 43 { 44 int pid; 45 }; 46 47 /* Open up a raw pipe */ 48 49 static int 50 pipe_open (struct serial *scb, const char *name) 51 { 52 #if !HAVE_SOCKETPAIR 53 return -1; 54 #else 55 struct pipe_state *state; 56 /* This chunk: */ 57 /* Copyright (c) 1988, 1993 58 * The Regents of the University of California. All rights reserved. 59 * 60 * This code is derived from software written by Ken Arnold and 61 * published in UNIX Review, Vol. 6, No. 8. 62 */ 63 int pdes[2]; 64 int err_pdes[2]; 65 int pid; 66 if (socketpair (AF_UNIX, SOCK_STREAM, 0, pdes) < 0) 67 return -1; 68 if (socketpair (AF_UNIX, SOCK_STREAM, 0, err_pdes) < 0) 69 return -1; 70 71 /* Create the child process to run the command in. Note that the 72 apparent call to vfork() below *might* actually be a call to 73 fork() due to the fact that autoconf will ``#define vfork fork'' 74 on certain platforms. */ 75 pid = vfork (); 76 77 /* Error. */ 78 if (pid == -1) 79 { 80 close (pdes[0]); 81 close (pdes[1]); 82 close (err_pdes[0]); 83 close (err_pdes[1]); 84 return -1; 85 } 86 87 if (fcntl (err_pdes[0], F_SETFL, O_NONBLOCK) == -1) 88 { 89 close (err_pdes[0]); 90 close (err_pdes[1]); 91 err_pdes[0] = err_pdes[1] = -1; 92 } 93 94 /* Child. */ 95 if (pid == 0) 96 { 97 /* re-wire pdes[1] to stdin/stdout */ 98 close (pdes[0]); 99 if (pdes[1] != STDOUT_FILENO) 100 { 101 dup2 (pdes[1], STDOUT_FILENO); 102 close (pdes[1]); 103 } 104 dup2 (STDOUT_FILENO, STDIN_FILENO); 105 106 if (err_pdes[0] != -1) 107 { 108 close (err_pdes[0]); 109 dup2 (err_pdes[1], STDERR_FILENO); 110 close (err_pdes[1]); 111 } 112 #if 0 113 /* close any stray FD's - FIXME - how? */ 114 /* POSIX.2 B.3.2.2 "popen() shall ensure that any streams 115 from previous popen() calls that remain open in the 116 parent process are closed in the new child process. */ 117 for (old = pidlist; old; old = old->next) 118 close (fileno (old->fp)); /* don't allow a flush */ 119 #endif 120 execl ("/bin/sh", "sh", "-c", name, (char *) 0); 121 _exit (127); 122 } 123 124 /* Parent. */ 125 close (pdes[1]); 126 /* :end chunk */ 127 state = XMALLOC (struct pipe_state); 128 state->pid = pid; 129 scb->fd = pdes[0]; 130 scb->error_fd = err_pdes[0]; 131 scb->state = state; 132 133 /* If we don't do this, GDB simply exits when the remote side dies. */ 134 signal (SIGPIPE, SIG_IGN); 135 return 0; 136 #endif 137 } 138 139 static void 140 pipe_close (struct serial *scb) 141 { 142 struct pipe_state *state = scb->state; 143 if (state != NULL) 144 { 145 int pid = state->pid; 146 close (scb->fd); 147 scb->fd = -1; 148 xfree (state); 149 scb->state = NULL; 150 kill (pid, SIGTERM); 151 /* Might be useful to check that the child does die. */ 152 } 153 } 154 155 static struct serial_ops pipe_ops; 156 157 void 158 _initialize_ser_pipe (void) 159 { 160 struct serial_ops *ops = XMALLOC (struct serial_ops); 161 memset (ops, 0, sizeof (struct serial_ops)); 162 ops->name = "pipe"; 163 ops->next = 0; 164 ops->open = pipe_open; 165 ops->close = pipe_close; 166 ops->readchar = ser_base_readchar; 167 ops->write = ser_base_write; 168 ops->flush_output = ser_base_flush_output; 169 ops->flush_input = ser_base_flush_input; 170 ops->send_break = ser_base_send_break; 171 ops->go_raw = ser_base_raw; 172 ops->get_tty_state = ser_base_get_tty_state; 173 ops->set_tty_state = ser_base_set_tty_state; 174 ops->print_tty_state = ser_base_print_tty_state; 175 ops->noflush_set_tty_state = ser_base_noflush_set_tty_state; 176 ops->setbaudrate = ser_base_setbaudrate; 177 ops->setstopbits = ser_base_setstopbits; 178 ops->drain_output = ser_base_drain_output; 179 ops->async = ser_base_async; 180 ops->read_prim = ser_unix_read_prim; 181 ops->write_prim = ser_unix_write_prim; 182 serial_add_interface (ops); 183 } 184