/******************************************** 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. ********************************************/ /*$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 #include #include #ifdef V7 #include /* defines FIOCLEX */ #endif #ifndef NO_FCNTL_H #include #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 */ #if HAVE_FAKE_PIPES int inpipe_exit ; #endif PTR ptr ; /* FIN* or FILE* */ } FILE_NODE ; static FILE_NODE *file_list ; /* Prototypes for local functions */ static FILE *PROTO(tfopen, (char *, char *)) ; static void PROTO(efflush, (FILE*)) ; static void PROTO(add_to_child_list, (int, int)) ; static struct child *PROTO(remove_from_child_list, (int)) ; extern int PROTO(isatty, (int)) ; static void PROTO(close_error, (FILE_NODE *p)); /* find a file on file_list */ 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 = ZMALLOC(FILE_NODE) ; switch (p->type = type) { case F_TRUNC: #if MSDOS ostr = (binmode() & 2) ? "wb" : "w" ; #else ostr = "w" ; #endif if (!(p->ptr = (PTR) tfopen(name, ostr))) goto out_failure ; break ; case F_APPEND: #if 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 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 */ } /* 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(sval) 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) ; #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) ; retval = 0 ; break ; case PIPE_IN: FINclose((FIN *) p->ptr) ; #if HAVE_REAL_PIPES retval = wait_for(p->pid) ; #endif #if 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(sval) 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() { FILE_NODE *p ; for(p=file_list; p ; p = p->link) if (IS_OUTPUT(p->type)) efflush((FILE*)p->ptr) ; } static void efflush(fp) 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 */ #if 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() { 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 #if HAVE_FAKE_PIPES /* pipes are faked with temp files */ void close_fake_pipes() { 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 */ 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: 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(pid, exit_status) int pid, 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(pid) 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(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) ; } /* 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() /* 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(name, mode) char *name, *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(fp) 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() { 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(p) FILE_NODE *p ; { errmsg(errno, "close failed on file %s", p->name->str) ; mawk_exit(2) ; }