1/* Copyright (C) 1993, 1997 Free Software Foundation, Inc. 2 This file is part of the GNU IO Library. 3 Written by Per Bothner <bothner@cygnus.com>. 4 5 This library is free software; you can redistribute it and/or 6 modify it under the terms of the GNU General Public License as 7 published by the Free Software Foundation; either version 2, or (at 8 your option) any later version. 9 10 This library is distributed in the hope that it will be useful, but 11 WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 General Public License for more details. 14 15 You should have received a copy of the GNU General Public License 16 along with this library; see the file COPYING. If not, write to 17 the Free Software Foundation, 59 Temple Place - Suite 330, Boston, 18 MA 02111-1307, USA. 19 20 As a special exception, if you link this library with files 21 compiled with a GNU compiler to produce an executable, this does 22 not cause the resulting executable to be covered by the GNU General 23 Public License. This exception does not however invalidate any 24 other reasons why the executable file might be covered by the GNU 25 General Public License. */ 26 27#include "libioP.h" 28#if _IO_HAVE_SYS_WAIT 29#include <signal.h> 30#include <unistd.h> 31#ifdef __STDC__ 32#include <stdlib.h> 33#endif 34#ifdef _LIBC 35# include <unistd.h> 36#endif 37#include <sys/types.h> 38#include <sys/wait.h> 39 40#ifndef _IO_fork 41#define _IO_fork vfork /* defined in libiberty, if needed */ 42extern _IO_pid_t _IO_fork __P ((void)); 43#endif 44 45#endif /* _IO_HAVE_SYS_WAIT */ 46 47#ifndef _IO_pipe 48#define _IO_pipe pipe 49extern int _IO_pipe __P ((int des[2])); 50#endif 51 52#ifndef _IO_dup2 53#define _IO_dup2 dup2 54extern int _IO_dup2 __P ((int fd, int fd2)); 55#endif 56 57#ifndef _IO_waitpid 58#define _IO_waitpid waitpid 59#endif 60 61#ifndef _IO_execl 62#define _IO_execl execl 63#endif 64#ifndef _IO__exit 65#define _IO__exit _exit 66#endif 67 68#ifndef _IO_close 69#define _IO_close close 70#endif 71 72struct _IO_proc_file 73{ 74 struct _IO_FILE_plus file; 75 /* Following fields must match those in class procbuf (procbuf.h) */ 76 _IO_pid_t pid; 77 struct _IO_proc_file *next; 78}; 79typedef struct _IO_proc_file _IO_proc_file; 80 81static struct _IO_proc_file *proc_file_chain = NULL; 82 83_IO_FILE * 84_IO_proc_open (fp, command, mode) 85 _IO_FILE *fp; 86 const char *command; 87 const char *mode; 88{ 89#if _IO_HAVE_SYS_WAIT 90 volatile int read_or_write; 91 volatile int parent_end, child_end; 92 int pipe_fds[2]; 93 _IO_pid_t child_pid; 94 if (_IO_file_is_open (fp)) 95 return NULL; 96 if (_IO_pipe (pipe_fds) < 0) 97 return NULL; 98 if (mode[0] == 'r') 99 { 100 parent_end = pipe_fds[0]; 101 child_end = pipe_fds[1]; 102 read_or_write = _IO_NO_WRITES; 103 } 104 else 105 { 106 parent_end = pipe_fds[1]; 107 child_end = pipe_fds[0]; 108 read_or_write = _IO_NO_READS; 109 } 110 ((_IO_proc_file *) fp)->pid = child_pid = _IO_fork (); 111 if (child_pid == 0) 112 { 113 int child_std_end = mode[0] == 'r' ? 1 : 0; 114 _IO_close (parent_end); 115 if (child_end != child_std_end) 116 { 117 _IO_dup2 (child_end, child_std_end); 118 _IO_close (child_end); 119 } 120 /* POSIX.2: "popen() shall ensure that any streams from previous 121 popen() calls that remain open in the parent process are closed 122 in the new child process." */ 123 while (proc_file_chain) 124 { 125 _IO_close (_IO_fileno ((_IO_FILE *) proc_file_chain)); 126 proc_file_chain = proc_file_chain->next; 127 } 128 129 _IO_execl ("/bin/sh", "sh", "-c", command, (char *) 0); 130 _IO__exit (127); 131 } 132 _IO_close (child_end); 133 if (child_pid < 0) 134 { 135 _IO_close (parent_end); 136 return NULL; 137 } 138 _IO_fileno (fp) = parent_end; 139 140 /* Link into proc_file_chain. */ 141 ((_IO_proc_file *) fp)->next = proc_file_chain; 142 proc_file_chain = (_IO_proc_file *) fp; 143 144 _IO_mask_flags (fp, read_or_write, _IO_NO_READS|_IO_NO_WRITES); 145 return fp; 146#else /* !_IO_HAVE_SYS_WAIT */ 147 return NULL; 148#endif 149} 150 151_IO_FILE * 152_IO_popen (command, mode) 153 const char *command; 154 const char *mode; 155{ 156 struct locked_FILE 157 { 158 struct _IO_proc_file fpx; 159#ifdef _IO_MTSAFE_IO 160 _IO_lock_t lock; 161#endif 162 } *new_f; 163 _IO_FILE *fp; 164 165 new_f = (struct locked_FILE *) malloc (sizeof (struct locked_FILE)); 166 if (new_f == NULL) 167 return NULL; 168#ifdef _IO_MTSAFE_IO 169 new_f->fpx.file.file._lock = &new_f->lock; 170#endif 171 fp = (_IO_FILE*)&new_f->fpx; 172 _IO_init (fp, 0); 173 _IO_JUMPS (fp) = &_IO_proc_jumps; 174 _IO_file_init (fp); 175#if !_IO_UNIFIED_JUMPTABLES 176 ((struct _IO_FILE_plus *) fp)->vtable = NULL; 177#endif 178 if (_IO_proc_open (fp, command, mode) != NULL) 179 return fp; 180 free (new_f); 181 return NULL; 182} 183 184#ifdef strong_alias 185strong_alias (_IO_popen, popen); 186#endif 187 188int 189_IO_proc_close (fp) 190 _IO_FILE *fp; 191{ 192 /* This is not name-space clean. FIXME! */ 193#if _IO_HAVE_SYS_WAIT 194 int wstatus; 195 _IO_proc_file **ptr = &proc_file_chain; 196 _IO_pid_t wait_pid; 197 int status = -1; 198 199 /* Unlink from proc_file_chain. */ 200 for ( ; *ptr != NULL; ptr = &(*ptr)->next) 201 { 202 if (*ptr == (_IO_proc_file *) fp) 203 { 204 *ptr = (*ptr)->next; 205 status = 0; 206 break; 207 } 208 } 209 210 if (status < 0 || _IO_close (_IO_fileno(fp)) < 0) 211 return -1; 212 /* POSIX.2 Rationale: "Some historical implementations either block 213 or ignore the signals SIGINT, SIGQUIT, and SIGHUP while waiting 214 for the child process to terminate. Since this behavior is not 215 described in POSIX.2, such implementations are not conforming." */ 216 do 217 { 218 wait_pid = _IO_waitpid (((_IO_proc_file *) fp)->pid, &wstatus, 0); 219 } 220 while (wait_pid == -1 && errno == EINTR); 221 if (wait_pid == -1) 222 return -1; 223 return wstatus; 224#else /* !_IO_HAVE_SYS_WAIT */ 225 return -1; 226#endif 227} 228 229struct _IO_jump_t _IO_proc_jumps = { 230 JUMP_INIT_DUMMY, 231 JUMP_INIT(finish, _IO_file_finish), 232 JUMP_INIT(overflow, _IO_file_overflow), 233 JUMP_INIT(underflow, _IO_file_underflow), 234 JUMP_INIT(uflow, _IO_default_uflow), 235 JUMP_INIT(pbackfail, _IO_default_pbackfail), 236 JUMP_INIT(xsputn, _IO_file_xsputn), 237 JUMP_INIT(xsgetn, _IO_default_xsgetn), 238 JUMP_INIT(seekoff, _IO_file_seekoff), 239 JUMP_INIT(seekpos, _IO_default_seekpos), 240 JUMP_INIT(setbuf, _IO_file_setbuf), 241 JUMP_INIT(sync, _IO_file_sync), 242 JUMP_INIT(doallocate, _IO_file_doallocate), 243 JUMP_INIT(read, _IO_file_read), 244 JUMP_INIT(write, _IO_file_write), 245 JUMP_INIT(seek, _IO_file_seek), 246 JUMP_INIT(close, _IO_proc_close), 247 JUMP_INIT(stat, _IO_file_stat) 248}; 249