2 * Copyright (c) 1991, 1993
3 * The Regents of the University of California. All rights reserved.
5 * This code is derived from software contributed to Berkeley by
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 static char sccsid
[] = "@(#)input.c 8.3 (Berkeley) 6/9/95";
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
41 #include <stdio.h> /* defines BUFSIZ */
49 * This file implements the input routines used by the parser.
62 #include "myhistedit.h"
65 #define EOF_NLEFT -99 /* value of parsenleft when EOF pushed back */
68 struct strpush
*prev
; /* preceding string on stack */
69 const char *prevstring
;
72 struct alias
*ap
; /* if push was associated with an alias */
76 * The parsefile structure pointed to by the global variable parsefile
77 * contains information about the current file being read.
81 struct parsefile
*prev
; /* preceding file on stack */
82 int linno
; /* current line */
83 int fd
; /* file descriptor (or -1 if string) */
84 int nleft
; /* number of chars left in this line */
85 int lleft
; /* number of lines left in this buffer */
86 const char *nextc
; /* next char in buffer */
87 char *buf
; /* input buffer */
88 struct strpush
*strpush
; /* for pushing strings at this level */
89 struct strpush basestrpush
; /* so pushing one is fast */
93 int plinno
= 1; /* input line number */
94 int parsenleft
; /* copy of parsefile->nleft */
95 static int parselleft
; /* copy of parsefile->lleft */
96 const char *parsenextc
; /* copy of parsefile->nextc */
97 static char basebuf
[BUFSIZ
+ 1];/* buffer for top level input file */
98 static struct parsefile basepf
= { /* top level input file */
102 static struct parsefile
*parsefile
= &basepf
; /* current input file */
103 int whichprompt
; /* 1 == PS1, 2 == PS2 */
105 EditLine
*el
; /* cookie for editline package */
107 static void pushfile(void);
108 static int preadfd(void);
109 static void popstring(void);
115 parselleft
= parsenleft
= 0; /* clear input buffer */
121 * Read a character from the script, returning PEOF on end of file.
122 * Nul characters in the input are silently discarded.
128 return pgetc_macro();
136 parsenextc
= parsefile
->buf
;
140 if (parsefile
->fd
== 0 && el
) {
141 static const char *rl_cp
;
146 rl_cp
= el_gets(el
, &el_len
);
149 nr
= el_len
== 0 ? 0 : -1;
154 memcpy(parsefile
->buf
, rl_cp
, nr
);
163 nr
= read(parsefile
->fd
, parsefile
->buf
, BUFSIZ
);
169 if (parsefile
->fd
== 0 && errno
== EWOULDBLOCK
) {
170 int flags
= fcntl(0, F_GETFL
, 0);
171 if (flags
>= 0 && flags
& O_NONBLOCK
) {
172 flags
&=~ O_NONBLOCK
;
173 if (fcntl(0, F_SETFL
, flags
) >= 0) {
174 out2fmt_flush("sh: turning off NDELAY mode\n");
186 * Refill the input buffer and return the next input character:
188 * 1) If a string was pushed back on the input, pop it;
189 * 2) If an EOF was pushed back (parsenleft == EOF_NLEFT) or we are reading
190 * from a string so we can't refill the buffer, return EOF.
191 * 3) If there is more in this buffer, use it else call read to fill it.
192 * 4) Process input up to the next newline, deleting nul characters.
202 while (parsefile
->strpush
) {
204 * Add a space to the end of an alias to ensure that the
205 * alias remains in use while parsing its last word.
206 * This avoids alias recursions.
208 if (parsenleft
== -1 && parsefile
->strpush
->ap
!= NULL
)
211 if (--parsenleft
>= 0)
212 return (*parsenextc
++);
214 if (parsenleft
== EOF_NLEFT
|| parsefile
->buf
== NULL
)
220 if (parselleft
<= 0) {
221 if ((parselleft
= preadfd()) == -1) {
222 parselleft
= parsenleft
= EOF_NLEFT
;
227 q
= p
= parsefile
->buf
+ (parsenextc
- parsefile
->buf
);
229 /* delete nul characters */
230 for (more
= 1; more
;) {
237 parsenleft
= q
- parsenextc
;
238 more
= 0; /* Stop processing here */
247 if (--parselleft
<= 0) {
248 parsenleft
= q
- parsenextc
- 1;
260 if (parsefile
->fd
== 0 && hist
&&
261 parsenextc
[strspn(parsenextc
, " \t\n")] != '\0') {
264 history(hist
, &he
, whichprompt
== 1 ? H_ENTER
: H_ADD
,
277 return *parsenextc
++;
281 * Returns if we are certain we are at EOF. Does not cause any more input
282 * to be read from the outside world.
290 if (parsefile
->strpush
)
292 if (parsenleft
== EOF_NLEFT
|| parsefile
->buf
== NULL
)
298 * Undo the last call to pgetc. Only one character may be pushed back.
299 * PEOF may be pushed back.
310 * Push a string back onto the input at this current parsefile level.
311 * We handle aliases this way.
314 pushstring(const char *s
, int len
, struct alias
*ap
)
319 /*out2fmt_flush("*** calling pushstring: %s, %d\n", s, len);*/
320 if (parsefile
->strpush
) {
321 sp
= ckmalloc(sizeof (struct strpush
));
322 sp
->prev
= parsefile
->strpush
;
323 parsefile
->strpush
= sp
;
325 sp
= parsefile
->strpush
= &(parsefile
->basestrpush
);
326 sp
->prevstring
= parsenextc
;
327 sp
->prevnleft
= parsenleft
;
328 sp
->prevlleft
= parselleft
;
331 ap
->flag
|= ALIASINUSE
;
340 struct strpush
*sp
= parsefile
->strpush
;
344 if (parsenextc
!= sp
->ap
->val
&&
345 (parsenextc
[-1] == ' ' || parsenextc
[-1] == '\t'))
347 sp
->ap
->flag
&= ~ALIASINUSE
;
349 parsenextc
= sp
->prevstring
;
350 parsenleft
= sp
->prevnleft
;
351 parselleft
= sp
->prevlleft
;
352 /*out2fmt_flush("*** calling popstring: restoring to '%s'\n", parsenextc);*/
353 parsefile
->strpush
= sp
->prev
;
354 if (sp
!= &(parsefile
->basestrpush
))
360 * Set the input to take input from a file. If push is set, push the
361 * old input onto the stack first.
365 setinputfile(const char *fname
, int push
)
371 if ((fd
= open(fname
, O_RDONLY
| O_CLOEXEC_MAYBE
)) < 0)
372 error("cannot open %s: %s", fname
, strerror(errno
));
374 fd2
= fcntl(fd
, F_DUPFD_CLOEXEC_MAYBE
, 10);
377 error("Out of file descriptors");
380 setinputfd(fd
, push
);
386 * Like setinputfile, but takes an open file descriptor (which should have
387 * its FD_CLOEXEC flag already set). Call this with interrupts off.
391 setinputfd(int fd
, int push
)
393 #if !defined(O_CLOEXEC) || !defined(F_DUPFD_CLOEXEC)
394 fcntl(fd
, F_SETFD
, FD_CLOEXEC
);
398 parsefile
->buf
= ckmalloc(BUFSIZ
+ 1);
400 if (parsefile
->fd
> 0)
401 close(parsefile
->fd
);
403 if (parsefile
->buf
== NULL
)
404 parsefile
->buf
= ckmalloc(BUFSIZ
+ 1);
405 parselleft
= parsenleft
= 0;
411 * Like setinputfile, but takes input from a string.
415 setinputstring(const char *string
, int push
)
421 parselleft
= parsenleft
= strlen(string
);
422 parsefile
->buf
= NULL
;
430 * To handle the "." command, a stack of input files is used. Pushfile
431 * adds a new entry to the stack and popfile restores the previous level.
437 struct parsefile
*pf
;
439 parsefile
->nleft
= parsenleft
;
440 parsefile
->lleft
= parselleft
;
441 parsefile
->nextc
= parsenextc
;
442 parsefile
->linno
= plinno
;
443 pf
= (struct parsefile
*)ckmalloc(sizeof (struct parsefile
));
444 pf
->prev
= parsefile
;
447 pf
->basestrpush
.prev
= NULL
;
455 struct parsefile
*pf
= parsefile
;
464 parsefile
= pf
->prev
;
466 parsenleft
= parsefile
->nleft
;
467 parselleft
= parsefile
->lleft
;
468 parsenextc
= parsefile
->nextc
;
469 plinno
= parsefile
->linno
;
475 * Return current file (to go back to it later using popfilesupto()).
486 * Pop files until the given file is on top again. Useful for regular
487 * builtins that read shell commands from files or strings.
488 * If the given file is not an active file, an error is raised.
492 popfilesupto(struct parsefile
*file
)
494 while (parsefile
!= file
&& parsefile
!= &basepf
)
496 if (parsefile
!= file
)
497 error("popfilesupto() misused");
501 * Return to top level.
507 while (parsefile
!= &basepf
)
514 * Close the file(s) that the shell is reading commands from. Called
515 * after a fork is done.
522 if (parsefile
->fd
> 0) {
523 close(parsefile
->fd
);