mirror/mawk
1
0
Fork 0
mirror of https://github.com/ThomasDickey/mawk-snapshots.git synced 2026-01-26 19:09:15 +00:00
Code Issues Packages Projects Releases Wiki Activity
mawk/files.c
Thomas E. Dickey c5fab9101c snapshot of project "mawk", label t20090727
2009-07-27 23:31:27 -04:00

616 lines
12 KiB
C
Raw Blame History

/********************************************
files.c
copyright 1991-94. 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.
********************************************/
/*
* $MawkId: files.c,v 1.8 2009/07/27 15:46:04 tom Exp $
* @Log: files.c,v @
* Revision 1.9 1996/01/14 17:14:10 mike
* flush_all_output()
*
* Revision 1.8 1995/06/06 00:18:27 mike
* change mawk_exit(1) to mawk_exit(2)
*
* Revision 1.7 1994/12/11 20:48:50 mike
* fflush builtin
*
* Revision 1.6 1994/10/08 19:15:40 mike
* remove SM_DOS
*
* Revision 1.5 1994/04/17 20:01:37 mike
* recognize filename "/dev/stdout"
*
* Revision 1.4 1994/02/21 00:11:07 mike
* code cleanup
*
* Revision 1.3 1993/07/16 01:00:36 mike
* cleanup and indent
*
* Revision 5.5 1992/12/17 02:48:01 mike
* 1.1.2d changes for DOS
*
* Revision 5.4 1992/07/10 16:10:30 brennan
* patch2
* MsDOS: remove useless NO_BINMODE macro
* get process exit code on in pipes
*
* Revision 5.3 1992/04/07 20:21:17 brennan
* patch 2
* unbuffered output to a tty
*
* Revision 5.2 1992/04/07 16:03:08 brennan
* patch 2
* allow same filename for output and input, but use different descriptors
* E.g. < "/dev/tty" and > "/dev/tty"
*
* 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"
#include "init.h"
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#ifdef V7
#include <sgtty.h> /* defines FIOCLEX */
#endif
#ifndef NO_FCNTL_H
#include <fcntl.h>
#define CLOSE_ON_EXEC(fd) 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 a pipe */
/* holds temp file index under MSDOS */
#ifdef HAVE_FAKE_PIPES
int inpipe_exit;
#endif
PTR ptr; /* FIN* or FILE* */
} FILE_NODE;
static FILE_NODE *file_list;
/* Prototypes for local functions */
extern int isatty(int);
static FILE *tfopen(const char *, const char *);
static void efflush(FILE *);
static void close_error(FILE_NODE * p);
/* find a file on file_list */
PTR
file_find(STRING * sval, int type)
{
register FILE_NODE *p = file_list;
FILE_NODE *q = (FILE_NODE *) 0;
char *name = sval->str;
const char *ostr;
while (1) {
if (!p) {
/* open a new one */
p = ZMALLOC(FILE_NODE);
switch (p->type = type) {
case F_TRUNC:
#ifdef MSDOS
ostr = (binmode() & 2) ? "wb" : "w";
#else
ostr = "w";
#endif
if (!(p->ptr = (PTR) tfopen(name, ostr)))
goto out_failure;
break;
case F_APPEND:
#ifdef MSDOS
ostr = (binmode() & 2) ? "ab" : "a";
#else
ostr = "a";
#endif
if (!(p->ptr = (PTR) tfopen(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 defined(HAVE_REAL_PIPES) || defined(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 */
}
/* search is by name and type */
if (strcmp(name, p->name->str) == 0 &&
(p->type == type ||
/* no distinction between F_APPEND and F_TRUNC here */
(p->type >= F_APPEND && type >= F_APPEND))) {
/* found */
if (!q) /*at front of list */
return p->ptr;
/* delete from list for move to front */
q->link = p->link;
break; /* while loop */
}
q = p;
p = p->link;
} /* end while loop */
/* 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(2);
}
/* Close a file and delete it's node from the file_list.
Walk the whole list, in case a name has two nodes,
e.g. < "/dev/tty" and > "/dev/tty"
*/
int
file_close(STRING * sval)
{
FILE_NODE dummy;
register FILE_NODE *p;
FILE_NODE *q = &dummy; /* trails p */
FILE_NODE *hold;
char *name = sval->str;
int retval = -1;
dummy.link = p = file_list;
while (p) {
if (strcmp(name, p->name->str) == 0) {
/* found */
/* Remove it from the list first because we might be called
again if an error occurs leading to an infinite loop.
Note that we don't have to consider the list corruption
caused by a recursive call because it will never return. */
q->link = p->link;
file_list = dummy.link; /* maybe it was the first file */
switch (p->type) {
case F_TRUNC:
case F_APPEND:
if (fclose((FILE *) p->ptr) != 0)
close_error(p);
retval = 0;
break;
case PIPE_OUT:
if (fclose((FILE *) p->ptr) != 0)
close_error(p);
#ifdef HAVE_REAL_PIPES
retval = wait_for(p->pid);
#endif
#ifdef HAVE_FAKE_PIPES
retval = close_fake_outpipe(p->name->str, p->pid);
#endif
break;
case F_IN:
FINclose((FIN *) p->ptr);
retval = 0;
break;
case PIPE_IN:
FINclose((FIN *) p->ptr);
#ifdef HAVE_REAL_PIPES
retval = wait_for(p->pid);
#endif
#ifdef HAVE_FAKE_PIPES
{
char xbuff[100];
unlink(tmp_file_name(p->pid, xbuff));
retval = p->inpipe_exit;
}
#endif
break;
}
free_STRING(p->name);
hold = p;
p = p->link;
ZFREE(hold);
} else {
q = p;
p = p->link;
}
}
return retval;
}
/*
find an output file with name == sval and fflush it
*/
int
file_flush(STRING * sval)
{
int ret = -1;
register FILE_NODE *p = file_list;
unsigned len = sval->len;
char *str = sval->str;
if (len == 0) {
/* for consistency with gawk */
flush_all_output();
return 0;
}
while (p) {
if (IS_OUTPUT(p->type) &&
len == p->name->len &&
strcmp(str, p->name->str) == 0) {
ret = 0;
efflush((FILE *) p->ptr);
/* it's possible for a command and a file to have the same
name -- so keep looking */
}
p = p->link;
}
return ret;
}
void
flush_all_output(void)
{
FILE_NODE *p;
for (p = file_list; p; p = p->link)
if (IS_OUTPUT(p->type))
efflush((FILE *) p->ptr);
}
static void
efflush(FILE *fp)
{
if (fflush(fp) < 0) {
errmsg(errno, "unexpected write error");
mawk_exit(2);
}
}
/* When we exit, we need to close and wait for all output pipes */
#ifdef HAVE_REAL_PIPES
/* work around for bug in AIX 4.1 -- If there are exactly 16 or
32 or 48 ..., open files then the last one doesn't get flushed on
exit. So the following is now a misnomer as we'll really close
all output.
*/
void
close_out_pipes(void)
{
register FILE_NODE *p = file_list;
while (p) {
if (IS_OUTPUT(p->type)) {
if (fclose((FILE *) p->ptr) != 0) {
/* if another error occurs we do not want to be called
for the same file again */
file_list = p->link;
close_error(p);
}
if (p->type == PIPE_OUT)
wait_for(p->pid);
}
p = p->link;
}
}
#else
#ifdef HAVE_FAKE_PIPES /* pipes are faked with temp files */
void
close_fake_pipes(void)
{
register FILE_NODE *p = file_list;
char xbuff[100];
/* close input pipes first to free descriptors for children */
while (p) {
if (p->type == PIPE_IN) {
FINclose((FIN *) p->ptr);
unlink(tmp_file_name(p->pid, xbuff));
}
p = p->link;
}
/* doit again */
p = file_list;
while (p) {
if (p->type == PIPE_OUT) {
if (fclose(p->ptr) != 0)
close_error(p);
close_fake_outpipe(p->name->str, p->pid);
}
p = p->link;
}
}
#endif /* HAVE_FAKE_PIPES */
#endif /* ! HAVE_REAL_PIPES */
/* hardwire to /bin/sh for portability of programs */
const char *shell = "/bin/sh";
#ifdef HAVE_REAL_PIPES
PTR
get_pipe(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:
close(local_fd);
close(remote_fd);
return (PTR) 0;
case 0:
close(local_fd);
close(type == PIPE_IN);
dup(remote_fd);
close(remote_fd);
execl(shell, shell, "-c", name, (char *) 0);
errmsg(errno, "failed to exec %s -c %s", shell, name);
fflush(stderr);
_exit(128);
default:
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(int pid, int exit_status)
{
register struct child *p = ZMALLOC(struct child);
p->pid = pid;
p->exit_status = exit_status;
p->link = child_list;
child_list = p;
}
static struct child *
remove_from_child_list(int pid)
{
struct child dummy;
register struct child *p;
struct child *q = &dummy;
dummy.link = p = child_list;
while (p) {
if (p->pid == pid) {
q->link = p->link;
break;
} else {
q = p;
p = p->link;
}
}
child_list = dummy.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 and
put it on the dead children list
*/
int
wait_for(int pid)
{
int exit_status;
struct child *p;
int id;
if (pid == 0) {
id = wait(&exit_status);
add_to_child_list(id, exit_status);
}
/* see if an earlier wait() caught our child */
else 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 */
void
set_stderr(void) /* and stdout */
{
FILE_NODE *p, *q;
/* We insert stderr first to get it at the end of the list. This is
needed because we want to output errors encountered on closing
stdout. */
q = ZMALLOC(FILE_NODE);
q->link = (FILE_NODE *) 0;
q->type = F_TRUNC;
q->name = new_STRING("/dev/stderr");
q->ptr = (PTR) stderr;
p = ZMALLOC(FILE_NODE);
p->link = q;
p->type = F_TRUNC;
p->name = new_STRING("/dev/stdout");
p->ptr = (PTR) stdout;
file_list = p;
}
/* fopen() but no buffering to ttys */
static FILE *
tfopen(const char *name, const char *mode)
{
FILE *retval = fopen(name, mode);
if (retval) {
if (isatty(fileno(retval)))
setbuf(retval, (char *) 0);
else {
#ifdef MSDOS
enlarge_output_buffer(retval);
#endif
}
}
return retval;
}
#ifdef MSDOS
void
enlarge_output_buffer(FILE *fp)
{
if (setvbuf(fp, (char *) 0, _IOFBF, BUFFSZ) < 0) {
errmsg(errno, "setvbuf failed on fileno %d", fileno(fp));
mawk_exit(2);
}
}
void
stdout_init(void)
{
if (!isatty(1))
enlarge_output_buffer(stdout);
if (binmode() & 2) {
setmode(1, O_BINARY);
setmode(2, O_BINARY);
}
}
#endif /* MSDOS */
/* An error occured closing the file referred to by P. We tell the
user and terminate the program. */
static void
close_error(FILE_NODE * p)
{
errmsg(errno, "close failed on file %s", p->name->str);
mawk_exit(2);
}
Reference in New Issue View Git Blame Copy Permalink