1 /* Serial interface for a pipe to a separate program 2 Copyright 1999, 2000, 2001 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 2 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, write to the Free Software 20 Foundation, Inc., 59 Temple Place - Suite 330, 21 Boston, MA 02111-1307, USA. */ 22 23 #include "defs.h" 24 #include "serial.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 pid; 65 if (socketpair (AF_UNIX, SOCK_STREAM, 0, pdes) < 0) 66 return -1; 67 68 /* Create the child process to run the command in. Note that the 69 apparent call to vfork() below *might* actually be a call to 70 fork() due to the fact that autoconf will ``#define vfork fork'' 71 on certain platforms. */ 72 pid = vfork (); 73 74 /* Error. */ 75 if (pid == -1) 76 { 77 close (pdes[0]); 78 close (pdes[1]); 79 return -1; 80 } 81 82 /* Child. */ 83 if (pid == 0) 84 { 85 /* re-wire pdes[1] to stdin/stdout */ 86 close (pdes[0]); 87 if (pdes[1] != STDOUT_FILENO) 88 { 89 dup2 (pdes[1], STDOUT_FILENO); 90 close (pdes[1]); 91 } 92 dup2 (STDOUT_FILENO, STDIN_FILENO); 93 #if 0 94 /* close any stray FD's - FIXME - how? */ 95 /* POSIX.2 B.3.2.2 "popen() shall ensure that any streams 96 from previous popen() calls that remain open in the 97 parent process are closed in the new child process. */ 98 for (old = pidlist; old; old = old->next) 99 close (fileno (old->fp)); /* don't allow a flush */ 100 #endif 101 execl ("/bin/sh", "sh", "-c", name, (char *) 0); 102 _exit (127); 103 } 104 105 /* Parent. */ 106 close (pdes[1]); 107 /* :end chunk */ 108 state = XMALLOC (struct pipe_state); 109 state->pid = pid; 110 scb->fd = pdes[0]; 111 scb->state = state; 112 113 /* If we don't do this, GDB simply exits when the remote side dies. */ 114 signal (SIGPIPE, SIG_IGN); 115 return 0; 116 #endif 117 } 118 119 static void 120 pipe_close (struct serial *scb) 121 { 122 struct pipe_state *state = scb->state; 123 if (state != NULL) 124 { 125 int pid = state->pid; 126 close (scb->fd); 127 scb->fd = -1; 128 xfree (state); 129 scb->state = NULL; 130 kill (pid, SIGTERM); 131 /* Might be useful to check that the child does die. */ 132 } 133 } 134 135 static struct serial_ops pipe_ops; 136 137 void 138 _initialize_ser_pipe (void) 139 { 140 struct serial_ops *ops = XMALLOC (struct serial_ops); 141 memset (ops, 0, sizeof (struct serial_ops)); 142 ops->name = "pipe"; 143 ops->next = 0; 144 ops->open = pipe_open; 145 ops->close = pipe_close; 146 ops->readchar = ser_unix_readchar; 147 ops->write = ser_unix_write; 148 ops->flush_output = ser_unix_nop_flush_output; 149 ops->flush_input = ser_unix_flush_input; 150 ops->send_break = ser_unix_nop_send_break; 151 ops->go_raw = ser_unix_nop_raw; 152 ops->get_tty_state = ser_unix_nop_get_tty_state; 153 ops->set_tty_state = ser_unix_nop_set_tty_state; 154 ops->print_tty_state = ser_unix_nop_print_tty_state; 155 ops->noflush_set_tty_state = ser_unix_nop_noflush_set_tty_state; 156 ops->setbaudrate = ser_unix_nop_setbaudrate; 157 ops->setstopbits = ser_unix_nop_setstopbits; 158 ops->drain_output = ser_unix_nop_drain_output; 159 ops->async = ser_unix_async; 160 serial_add_interface (ops); 161 } 162