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Diffstat (limited to 'libio/iopopen.c')
| -rw-r--r-- | libio/iopopen.c | 222 |
1 files changed, 222 insertions, 0 deletions
diff --git a/libio/iopopen.c b/libio/iopopen.c new file mode 100644 index 0000000..ef6ad12 --- /dev/null +++ b/libio/iopopen.c @@ -0,0 +1,222 @@ +/* +Copyright (C) 1993 Free Software Foundation + +This file is part of the GNU IO Library. This library is free +software; you can redistribute it and/or modify it under the +terms of the GNU General Public License as published by the +Free Software Foundation; either version 2, or (at your option) +any later version. + +This library is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. + +You should have received a copy of the GNU General Public License +along with this library; see the file COPYING. If not, write to the Free +Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + +As a special exception, if you link this library with files +compiled with a GNU compiler to produce an executable, this does not cause +the resulting executable to be covered by the GNU General Public License. +This exception does not however invalidate any other reasons why +the executable file might be covered by the GNU General Public License. */ + +/* written by Per Bothner (bothner@cygnus.com) */ + +#define _POSIX_SOURCE +#include "libioP.h" +#include <sys/types.h> +#if _IO_HAVE_SYS_WAIT +#include <signal.h> +#include <unistd.h> +#ifdef __STDC__ +#include <stdlib.h> +#endif +#include <sys/wait.h> + +#ifndef _IO_fork +#define _IO_fork vfork /* defined in libiberty, if needed */ +_IO_pid_t _IO_fork(); +#endif + +#endif /* _IO_HAVE_SYS_WAIT */ + +#ifndef _IO_pipe +#define _IO_pipe pipe +extern int _IO_pipe(); +#endif + +#ifndef _IO_dup2 +#define _IO_dup2 dup2 +extern int _IO_dup2(); +#endif + +#ifndef _IO_waitpid +#define _IO_waitpid waitpid +#endif + +#ifndef _IO_execl +#define _IO_execl execl +#endif +#ifndef _IO__exit +#define _IO__exit _exit +#endif + +struct _IO_proc_file +{ + struct _IO_FILE_plus file; + /* Following fields must match those in class procbuf (procbuf.h) */ + _IO_pid_t pid; + struct _IO_proc_file *next; +}; +typedef struct _IO_proc_file _IO_proc_file; + +static struct _IO_proc_file *proc_file_chain = NULL; + +_IO_FILE * +DEFUN(_IO_proc_open, (fp, command, mode), + _IO_FILE* fp AND const char *command AND const char *mode) +{ +#if _IO_HAVE_SYS_WAIT + int read_or_write; + int pipe_fds[2]; + int parent_end, child_end; + _IO_pid_t child_pid; + if (_IO_file_is_open(fp)) + return NULL; + if (_IO_pipe(pipe_fds) < 0) + return NULL; + if (mode[0] == 'r') + { + parent_end = pipe_fds[0]; + child_end = pipe_fds[1]; + read_or_write = _IO_NO_WRITES; + } + else + { + parent_end = pipe_fds[1]; + child_end = pipe_fds[0]; + read_or_write = _IO_NO_READS; + } + ((_IO_proc_file*)fp)->pid = child_pid = _IO_fork(); + if (child_pid == 0) + { + int child_std_end = mode[0] == 'r' ? 1 : 0; + _IO_close(parent_end); + if (child_end != child_std_end) + { + _IO_dup2(child_end, child_std_end); + _IO_close(child_end); + } + /* Posix.2: "popen() shall ensure that any streams from previous + popen() calls that remain open in the parent process are closed + in the new child process." */ + while (proc_file_chain) + { + _IO_close (_IO_fileno ((_IO_FILE *) proc_file_chain)); + proc_file_chain = proc_file_chain->next; + } + + _IO_execl("/bin/sh", "sh", "-c", command, (char *)0); + _IO__exit(127); + } + _IO_close(child_end); + if (child_pid < 0) + { + _IO_close(parent_end); + return NULL; + } + _IO_fileno(fp) = parent_end; + + /* Link into proc_file_chain. */ + ((_IO_proc_file*)fp)->next = proc_file_chain; + proc_file_chain = (_IO_proc_file*)fp; + + _IO_mask_flags (fp, read_or_write, _IO_NO_READS|_IO_NO_WRITES); + return fp; +#else /* !_IO_HAVE_SYS_WAIT */ + return NULL; +#endif +} + +_IO_FILE * +DEFUN(_IO_popen, (command, mode), + const char *command AND const char *mode) +{ + _IO_proc_file *fpx = (_IO_proc_file*)malloc(sizeof(_IO_proc_file)); + _IO_FILE *fp = (_IO_FILE*)fpx; + if (fp == NULL) + return NULL; + _IO_init(fp, 0); + _IO_JUMPS(fp) = &_IO_proc_jumps; + _IO_file_init(fp); +#if !_IO_UNIFIED_JUMPTABLES + ((struct _IO_FILE_plus*)fp)->vtable = NULL; +#endif + if (_IO_proc_open (fp, command, mode) != NULL) + return fp; + free (fpx); + return NULL; +} + +int +DEFUN(_IO_proc_close, (fp), + _IO_FILE *fp) +{ + /* This is not name-space clean. FIXME! */ +#if _IO_HAVE_SYS_WAIT + int wstatus; + _IO_proc_file **ptr = &proc_file_chain; + _IO_pid_t wait_pid; + int status = -1; + + /* Unlink from proc_file_chain. */ + for ( ; *ptr != NULL; ptr = &(*ptr)->next) + { + if (*ptr == (_IO_proc_file*)fp) + { + *ptr = (*ptr)->next; + status = 0; + break; + } + } + + if (status < 0 || _IO_close(_IO_fileno(fp)) < 0) + return -1; + /* POSIX.2 Rationale: "Some historical implementations either block + or ignore the signals SIGINT, SIGQUIT, and SIGHUP while waiting + for the child process to terminate. Since this behavior is not + described in POSIX.2, such implementations are not conforming." */ + do + { + wait_pid = _IO_waitpid (((_IO_proc_file*)fp)->pid, &wstatus, 0); + } while (wait_pid == -1 && errno == EINTR); + if (wait_pid == -1) + return -1; + return wstatus; +#else /* !_IO_HAVE_SYS_WAIT */ + return -1; +#endif +} + +struct _IO_jump_t _IO_proc_jumps = { + JUMP_INIT_DUMMY, + JUMP_INIT(finish, _IO_file_finish), + JUMP_INIT(overflow, _IO_file_overflow), + JUMP_INIT(underflow, _IO_file_underflow), + JUMP_INIT(uflow, _IO_default_uflow), + JUMP_INIT(pbackfail, _IO_default_pbackfail), + JUMP_INIT(xsputn, _IO_file_xsputn), + JUMP_INIT(xsgetn, _IO_default_xsgetn), + JUMP_INIT(seekoff, _IO_file_seekoff), + JUMP_INIT(seekpos, _IO_default_seekpos), + JUMP_INIT(setbuf, _IO_file_setbuf), + JUMP_INIT(sync, _IO_file_sync), + JUMP_INIT(doallocate, _IO_file_doallocate), + JUMP_INIT(read, _IO_file_read), + JUMP_INIT(write, _IO_file_write), + JUMP_INIT(seek, _IO_file_seek), + JUMP_INIT(close, _IO_proc_close), + JUMP_INIT(stat, _IO_file_stat) +}; |