NetBSD/gnu/usr.bin/awk/files.c
1993-03-21 09:45:37 +00:00

393 lines
8.9 KiB
C

/********************************************
files.c
copyright 1991, Michael D. Brennan
This is a source file for mawk, an implementation of
the AWK programming language.
Mawk is distributed without warranty under the terms of
the GNU General Public License, version 2, 1991.
********************************************/
/*$Log: files.c,v $
/*Revision 1.1.1.1 1993/03/21 09:45:37 cgd
/*initial import of 386bsd-0.1 sources
/*
* Revision 5.1 91/12/05 07:56:00 brennan
* 1.1 pre-release
*
*/
/* files.c */
#include "mawk.h"
#include "files.h"
#include "memory.h"
#include "fin.h"
#ifdef V7
#include <sgtty.h> /* defines FIOCLEX */
#endif
#if HAVE_FCNTL_H
#include <fcntl.h>
#define CLOSE_ON_EXEC(fd) (void) fcntl(fd, F_SETFD, 1)
#else
#define CLOSE_ON_EXEC(fd) ioctl(fd, FIOCLEX, (PTR) 0)
#endif
/* We store dynamically created files on a linked linear
list with move to the front (big surprise) */
typedef struct file {
struct file *link ;
STRING *name ;
short type ;
int pid ; /* we need to wait() when we close an out pipe */
/* holds temp file index under MSDOS */
PTR ptr ; /* FIN* or FILE* */
} FILE_NODE ;
static FILE_NODE *file_list ;
void set_stderr()
{
file_list = ZMALLOC(FILE_NODE) ;
file_list->link = (FILE_NODE*) 0 ;
file_list->type = F_TRUNC ;
file_list->name = new_STRING("/dev/stderr") ;
file_list->ptr = (PTR) stderr ;
}
PTR file_find( sval, type )
STRING *sval ;
int type ;
{ register FILE_NODE *p = file_list ;
FILE_NODE *q = (FILE_NODE *) 0 ;
char *name = sval->str ;
char *ostr ;
while (1)
{
if ( !p ) /* open a new one */
{
p = (FILE_NODE*) zmalloc(sizeof(FILE_NODE)) ;
switch( p->type = type )
{
case F_TRUNC :
#if MSDOS && NO_BINMODE==0
ostr = (binmode()&2) ? "wb" : "w" ;
#else
ostr = "w" ;
#endif
if ( !(p->ptr = (PTR) fopen(name, ostr)) )
goto out_failure ;
break ;
case F_APPEND :
#if MSDOS && NO_BINMODE==0
ostr = (binmode()&2) ? "ab" : "a" ;
#else
ostr = "a" ;
#endif
if ( !(p->ptr = (PTR) fopen(name, ostr)) )
goto out_failure ;
break ;
case F_IN :
if ( !(p->ptr = (PTR) FINopen(name, 0)) )
{ zfree(p, sizeof(FILE_NODE)) ; return (PTR) 0 ; }
break ;
case PIPE_OUT :
case PIPE_IN :
#if HAVE_REAL_PIPES || HAVE_FAKE_PIPES
if ( !(p->ptr = get_pipe(name, type, &p->pid)) )
if ( type == PIPE_OUT ) goto out_failure ;
else
{ zfree(p, sizeof(FILE_NODE) ) ;
return (PTR) 0 ;
}
#else
rt_error("pipes not supported") ;
#endif
break ;
#ifdef DEBUG
default :
bozo("bad file type") ;
#endif
}
/* successful open */
p->name = sval ;
sval->ref_cnt++ ;
break ; /* while loop */
}
if ( strcmp(name, p->name->str) == 0 )
{ /* no distinction between F_APPEND and F_TRUNC here */
if ( p->type != type &&
(p->type < F_APPEND || type < F_APPEND)) goto type_failure ;
if ( !q ) /*at front of list */
return p->ptr ;
/* delete from list for move to front */
q->link = p->link ;
break ;
}
q = p ; p = p->link ;
}
/* put p at the front of the list */
p->link = file_list ;
return (PTR) (file_list = p)->ptr ;
out_failure:
errmsg(errno, "cannot open \"%s\" for output", name) ;
mawk_exit(1) ;
type_failure :
rt_error("use of file \"%s\"\n\tis inconsistent with previous use",
name) ;
}
/* close a file and delete it's node from the file_list */
int file_close( sval )
STRING *sval ;
{ register FILE_NODE *p = file_list ;
FILE_NODE *q = (FILE_NODE *) 0 ; /* trails p */
char *name = sval->str ;
int retval = 0 ;
while ( p )
if ( strcmp(name,p->name->str) == 0 ) /* found */
{
switch( p->type )
{
case F_TRUNC :
case F_APPEND :
(void) fclose((FILE *) p->ptr) ;
break ;
case PIPE_OUT :
(void) fclose((FILE *) p->ptr) ;
#if HAVE_REAL_PIPES
retval = wait_for(p->pid) ;
#endif
#if HAVE_FAKE_PIPES
retval = close_fake_outpipe(p->name->str,p->pid) ;
#endif
break ;
case F_IN :
FINclose((FIN *) p->ptr) ;
break ;
case PIPE_IN :
FINclose((FIN *) p->ptr) ;
#if HAVE_REAL_PIPES
retval = wait_for(p->pid) ;
#endif
#if HAVE_FAKE_PIPES
(void) unlink(tmp_file_name(p->pid)) ;
#endif
break ;
}
free_STRING(p->name) ;
if ( q ) q->link = p->link ;
else file_list = p->link ;
zfree(p, sizeof(FILE_NODE)) ;
return retval ;
}
else { q = p ; p = p->link ; }
/* its not on the list */
return -1 ;
}
/* When we exit, we need to close and wait for all output pipes */
#if HAVE_REAL_PIPES
void close_out_pipes()
{ register FILE_NODE *p = file_list ;
while ( p )
{ if ( p->type == PIPE_OUT )
{ (void) fclose((FILE *) p->ptr) ; (void) wait_for(p->pid) ; }
p = p->link ;
}
}
#else
#if HAVE_FAKE_PIPES /* pipes are faked with temp files */
void close_fake_pipes()
{ register FILE_NODE *p = file_list ;
/* close input pipes first to free descriptors for children */
while ( p )
{
if ( p->type == PIPE_IN )
{ FINclose((FIN *) p->ptr) ;
(void) unlink(tmp_file_name(p->pid)) ;
}
p = p->link ;
}
/* doit again */
p = file_list ;
while ( p )
{
if ( p->type == PIPE_OUT )
{
(void) fclose(p->ptr) ;
(void) close_fake_outpipe(p->name->str,p->pid) ;
}
p = p->link ;
}
}
#endif
#endif
/* hardwire to /bin/sh for portability of programs */
char *shell = "/bin/sh" ;
#if HAVE_REAL_PIPES
PTR get_pipe( name, type, pid_ptr)
char *name ;
int type ;
int *pid_ptr ;
{ int the_pipe[2], local_fd, remote_fd ;
if ( pipe(the_pipe) == -1 ) return (PTR) 0 ;
local_fd = the_pipe[type == PIPE_OUT] ;
remote_fd = the_pipe[type == PIPE_IN ] ;
/* to keep output ordered correctly */
fflush(stdout) ; fflush(stderr) ;
switch( *pid_ptr = fork() )
{ case -1 :
(void) close(local_fd) ;
(void) close(remote_fd) ;
return (PTR) 0 ;
case 0 :
(void) close(local_fd) ;
(void) close(type == PIPE_IN) ;
(void) dup( remote_fd ) ;
(void) close( remote_fd ) ;
(void) execl(shell, shell, "-c", name, (char *) 0 ) ;
errmsg(errno, "failed to exec %s -c %s" , shell, name) ;
fflush(stderr) ;
_exit(128) ;
default :
(void) close(remote_fd) ;
/* we could deadlock if future child inherit the local fd ,
set close on exec flag */
CLOSE_ON_EXEC(local_fd) ;
break ;
}
return type == PIPE_IN ? (PTR) FINdopen(local_fd, 0) :
(PTR) fdopen(local_fd, "w") ;
}
/*------------ children ------------------*/
/* we need to wait for children at the end of output pipes to
complete so we know any files they have created are complete */
/* dead children are kept on this list */
static struct child {
int pid ;
int exit_status ;
struct child *link ;
} *child_list ;
static void add_to_child_list(pid, exit_status)
int pid, exit_status ;
{ register struct child *p =
(struct child *) zmalloc(sizeof(struct child)) ;
p->pid = pid ; p->exit_status = exit_status ;
p->link = child_list ; child_list = p ;
}
static struct child *remove_from_child_list(pid)
int pid ;
{ register struct child *p = child_list ;
struct child *q = (struct child *) 0 ;
while ( p )
if ( p->pid == pid )
{
if ( q ) q->link = p->link ;
else child_list = p->link ;
break ;
}
else { q = p ; p = p->link ; }
return p ; /* null return if not in the list */
}
/* wait for a specific child to complete and return its
exit status
If pid is zero, wait for any single child
*/
int wait_for(pid)
int pid ;
{ int exit_status ;
struct child *p ;
int id ;
if ( pid == 0 )
{
id = wait(&exit_status) ;
add_to_child_list(id, exit_status) ;
}
else
/* see if an earlier wait() caught our child */
if ( p = remove_from_child_list(pid) )
{ exit_status = p->exit_status ;
ZFREE(p) ;
}
else /* need to really wait */
while ( (id = wait(&exit_status)) != pid )
if ( id == -1 ) /* can't happen */ bozo("wait_for") ;
else
{ /* we got the exit status of another child
put it on the child list and try again */
add_to_child_list(id, exit_status ) ;
}
if ( exit_status & 0xff )
exit_status = 128 + (exit_status & 0xff) ;
else exit_status = (exit_status & 0xff00)>>8 ;
return exit_status ;
}
#endif /* HAVE_REAL_PIPES */