usr/dash/input.c

/*-
 * Copyright (c) 1991, 1993
 *	The Regents of the University of California.  All rights reserved.
 * Copyright (c) 1997-2005
 *	Herbert Xu <herbert@gondor.apana.org.au>.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Kenneth Almquist.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <stdio.h>	/* defines BUFSIZ */
#include <fcntl.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>

/*
 * This file implements the input routines used by the parser.
 */

#include "shell.h"
#include "redir.h"
#include "syntax.h"
#include "input.h"
#include "output.h"
#include "options.h"
#include "memalloc.h"
#include "error.h"
#include "alias.h"
#include "parser.h"
#include "main.h"
#include "var.h"
#ifndef SMALL
#include "myhistedit.h"
#endif

#ifdef HETIO
#include "hetio.h"
#endif

#define EOF_NLEFT -99		/* value of parsenleft when EOF pushed back */
#define IBUFSIZ (BUFSIZ + 1)

MKINIT
struct strpush {
	struct strpush *prev;	/* preceding string on stack */
	char *prevstring;
	int prevnleft;
	struct alias *ap;	/* if push was associated with an alias */
	char *string;		/* remember the string since it may change */
};

/*
 * The parsefile structure pointed to by the global variable parsefile
 * contains information about the current file being read.
 */

MKINIT
struct parsefile {
	struct parsefile *prev;	/* preceding file on stack */
	int linno;		/* current line */
	int fd;			/* file descriptor (or -1 if string) */
	int nleft;		/* number of chars left in this line */
	int lleft;		/* number of chars left in this buffer */
	char *nextc;		/* next char in buffer */
	char *buf;		/* input buffer */
	struct strpush *strpush; /* for pushing strings at this level */
	struct strpush basestrpush; /* so pushing one is fast */
};


int plinno = 1;			/* input line number */
int parsenleft;			/* copy of parsefile->nleft */
MKINIT int parselleft;		/* copy of parsefile->lleft */
char *parsenextc;		/* copy of parsefile->nextc */
MKINIT struct parsefile basepf;	/* top level input file */
MKINIT char basebuf[IBUFSIZ];	/* buffer for top level input file */
struct parsefile *parsefile = &basepf;	/* current input file */
int whichprompt;		/* 1 == PS1, 2 == PS2 */

#ifndef SMALL
EditLine *el;			/* cookie for editline package */
#endif

STATIC void pushfile(void);
static int preadfd(void);
static void setinputfd(int fd, int push);

#ifdef mkinit
INCLUDE <stdio.h>
INCLUDE "input.h"
INCLUDE "error.h"

INIT {
	basepf.nextc = basepf.buf = basebuf;
}

RESET {
	parselleft = parsenleft = 0;	/* clear input buffer */
	popallfiles();
}
#endif


/*
 * Read a character from the script, returning PEOF on end of file.
 * Nul characters in the input are silently discarded.
 */

int
pgetc(void)
{
	return pgetc_macro();
}


/*
 * Same as pgetc(), but ignores PEOA.
 */

int
pgetc2()
{
	int c;
	do {
		c = pgetc_macro();
	} while (c == PEOA);
	return c;
}


static int
preadfd(void)
{
	int nr;
	char *buf =  parsefile->buf;
	parsenextc = buf;

retry:
#ifndef SMALL
	if (parsefile->fd == 0 && el) {
		static const char *rl_cp;
		static int el_len;

		if (rl_cp == NULL)
			rl_cp = el_gets(el, &el_len);
		if (rl_cp == NULL)
			nr = 0;
		else {
			nr = el_len;
			if (nr > IBUFSIZ - 1)
				nr = IBUFSIZ - 1;
			memcpy(buf, rl_cp, nr);
			if (nr != el_len) {
				el_len -= nr;
				rl_cp += nr;
			} else
				rl_cp = 0;
		}

	} else
#endif

#ifdef HETIO
		nr = hetio_read_input(parsefile->fd);
		if (nr == -255)
#endif
		nr = read(parsefile->fd, buf, IBUFSIZ - 1);


	if (nr < 0) {
		if (errno == EINTR)
			goto retry;
		if (parsefile->fd == 0 && errno == EWOULDBLOCK) {
			int flags = fcntl(0, F_GETFL, 0);
			if (flags >= 0 && flags & O_NONBLOCK) {
				flags &=~ O_NONBLOCK;
				if (fcntl(0, F_SETFL, flags) >= 0) {
					out2str("sh: turning off NDELAY mode\n");
					goto retry;
				}
			}
		}
	}
	return nr;
}

/*
 * Refill the input buffer and return the next input character:
 *
 * 1) If a string was pushed back on the input, pop it;
 * 2) If an EOF was pushed back (parsenleft == EOF_NLEFT) or we are reading
 *    from a string so we can't refill the buffer, return EOF.
 * 3) If the is more stuff in this buffer, use it else call read to fill it.
 * 4) Process input up to the next newline, deleting nul characters.
 */

int
preadbuffer(void)
{
	char *q;
	int more;
#ifndef SMALL
	int something;
#endif
	char savec;

	while (unlikely(parsefile->strpush)) {
		if (
			parsenleft == -1 && parsefile->strpush->ap &&
			parsenextc[-1] != ' ' && parsenextc[-1] != '\t'
		) {
			return PEOA;
		}
		popstring();
		if (--parsenleft >= 0)
			return (signed char)*parsenextc++;
	}
	if (unlikely(parsenleft == EOF_NLEFT || parsefile->buf == NULL))
		return PEOF;
	flushout(&output);
#ifdef FLUSHERR
	flushout(&errout);
#endif

	more = parselleft;
	if (more <= 0) {
again:
		if ((more = preadfd()) <= 0) {
			parselleft = parsenleft = EOF_NLEFT;
			return PEOF;
		}
	}

	q = parsenextc;

	/* delete nul characters */
#ifndef SMALL
	something = 0;
#endif
	for (;;) {
		int c;

		more--;
		c = *q;

		if (!c)
			memmove(q, q + 1, more);
		else {
			q++;

			if (c == '\n') {
				parsenleft = q - parsenextc - 1;
				break;
			}

#ifndef SMALL
			switch (c) {
			default:
				something = 1;
				/* fall through */
			case '\t':
			case ' ':
				break;
			}
#endif
		}

		if (more <= 0) {
			parsenleft = q - parsenextc - 1;
			if (parsenleft < 0)
				goto again;
			break;
		}
	}
	parselleft = more;

	savec = *q;
	*q = '\0';

#ifndef SMALL
	if (parsefile->fd == 0 && hist && something) {
		HistEvent he;
		INTOFF;
		history(hist, &he, whichprompt == 1? H_ENTER : H_APPEND,
		    parsenextc);
		INTON;
	}
#endif

	if (vflag) {
		out2str(parsenextc);
#ifdef FLUSHERR
		flushout(out2);
#endif
	}

	*q = savec;

	return (signed char)*parsenextc++;
}

/*
 * Undo the last call to pgetc.  Only one character may be pushed back.
 * PEOF may be pushed back.
 */

void
pungetc(void)
{
	parsenleft++;
	parsenextc--;
}

/*
 * Push a string back onto the input at this current parsefile level.
 * We handle aliases this way.
 */
void
pushstring(char *s, void *ap)
{
	struct strpush *sp;
	size_t len;

	len = strlen(s);
	INTOFF;
/*dprintf("*** calling pushstring: %s, %d\n", s, len);*/
	if (parsefile->strpush) {
		sp = ckmalloc(sizeof (struct strpush));
		sp->prev = parsefile->strpush;
		parsefile->strpush = sp;
	} else
		sp = parsefile->strpush = &(parsefile->basestrpush);
	sp->prevstring = parsenextc;
	sp->prevnleft = parsenleft;
	sp->ap = (struct alias *)ap;
	if (ap) {
		((struct alias *)ap)->flag |= ALIASINUSE;
		sp->string = s;
	}
	parsenextc = s;
	parsenleft = len;
	INTON;
}

void
popstring(void)
{
	struct strpush *sp = parsefile->strpush;

	INTOFF;
	if (sp->ap) {
		if (parsenextc[-1] == ' ' || parsenextc[-1] == '\t') {
			checkkwd |= CHKALIAS;
		}
		if (sp->string != sp->ap->val) {
			ckfree(sp->string);
		}
		sp->ap->flag &= ~ALIASINUSE;
		if (sp->ap->flag & ALIASDEAD) {
			unalias(sp->ap->name);
		}
	}
	parsenextc = sp->prevstring;
	parsenleft = sp->prevnleft;
/*dprintf("*** calling popstring: restoring to '%s'\n", parsenextc);*/
	parsefile->strpush = sp->prev;
	if (sp != &(parsefile->basestrpush))
		ckfree(sp);
	INTON;
}

/*
 * Set the input to take input from a file.  If push is set, push the
 * old input onto the stack first.
 */

int
setinputfile(const char *fname, int flags)
{
	int fd;

	INTOFF;
	if ((fd = open(fname, O_RDONLY)) < 0) {
		if (flags & INPUT_NOFILE_OK)
			goto out;
		sh_error("Can't open %s", fname);
	}
	if (fd < 10)
		fd = savefd(fd, fd);
	setinputfd(fd, flags & INPUT_PUSH_FILE);
out:
	INTON;
	return fd;
}


/*
 * Like setinputfile, but takes an open file descriptor.  Call this with
 * interrupts off.
 */

static void
setinputfd(int fd, int push)
{
	if (push) {
		pushfile();
		parsefile->buf = 0;
	}
	parsefile->fd = fd;
	if (parsefile->buf == NULL)
		parsefile->buf = ckmalloc(IBUFSIZ);
	parselleft = parsenleft = 0;
	plinno = 1;
}


/*
 * Like setinputfile, but takes input from a string.
 */

void
setinputstring(char *string)
{
	INTOFF;
	pushfile();
	parsenextc = string;
	parsenleft = strlen(string);
	parsefile->buf = NULL;
	plinno = 1;
	INTON;
}


/*
 * To handle the "." command, a stack of input files is used.  Pushfile
 * adds a new entry to the stack and popfile restores the previous level.
 */

STATIC void
pushfile(void)
{
	struct parsefile *pf;

	parsefile->nleft = parsenleft;
	parsefile->lleft = parselleft;
	parsefile->nextc = parsenextc;
	parsefile->linno = plinno;
	pf = (struct parsefile *)ckmalloc(sizeof (struct parsefile));
	pf->prev = parsefile;
	pf->fd = -1;
	pf->strpush = NULL;
	pf->basestrpush.prev = NULL;
	parsefile = pf;
}


void
popfile(void)
{
	struct parsefile *pf = parsefile;

	INTOFF;
	if (pf->fd >= 0)
		close(pf->fd);
	if (pf->buf)
		ckfree(pf->buf);
	while (pf->strpush)
		popstring();
	parsefile = pf->prev;
	ckfree(pf);
	parsenleft = parsefile->nleft;
	parselleft = parsefile->lleft;
	parsenextc = parsefile->nextc;
	plinno = parsefile->linno;
	INTON;
}


/*
 * Return to top level.
 */

void
popallfiles(void)
{
	while (parsefile != &basepf)
		popfile();
}


/*
 * Close the file(s) that the shell is reading commands from.  Called
 * after a fork is done.
 */

void
closescript(void)
{
	popallfiles();
	if (parsefile->fd > 0) {
		close(parsefile->fd);
		parsefile->fd = 0;
	}
}


int lineno_inc(void)
{
	int lineno = plinno++;

	setvarint("LINENO", lineno, 0);
	return lineno;
}
1	/*-
2	* Copyright (c) 1991, 1993
3	* The Regents of the University of California. All rights reserved.
4	* Copyright (c) 1997-2005
5	* Herbert Xu <herbert@gondor.apana.org.au>. All rights reserved.
6	*
7	* This code is derived from software contributed to Berkeley by
8	* Kenneth Almquist.
9	*
10	* Redistribution and use in source and binary forms, with or without
11	* modification, are permitted provided that the following conditions
12	* are met:
13	* 1. Redistributions of source code must retain the above copyright
14	* notice, this list of conditions and the following disclaimer.
15	* 2. Redistributions in binary form must reproduce the above copyright
16	* notice, this list of conditions and the following disclaimer in the
17	* documentation and/or other materials provided with the distribution.
18	* 3. Neither the name of the University nor the names of its contributors
19	* may be used to endorse or promote products derived from this software
20	* without specific prior written permission.
21	*
22	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32	* SUCH DAMAGE.
33	*/
34
35	#include <stdio.h> /* defines BUFSIZ */
36	#include <fcntl.h>
37	#include <unistd.h>
38	#include <stdlib.h>
39	#include <string.h>
40
41	/*
42	* This file implements the input routines used by the parser.
43	*/
44
45	#include "shell.h"
46	#include "redir.h"
47	#include "syntax.h"
48	#include "input.h"
49	#include "output.h"
50	#include "options.h"
51	#include "memalloc.h"
52	#include "error.h"
53	#include "alias.h"
54	#include "parser.h"
55	#include "main.h"
56	#include "var.h"
57	#ifndef SMALL
58	#include "myhistedit.h"
59	#endif
60
61	#ifdef HETIO
62	#include "hetio.h"
63	#endif
64
65	#define EOF_NLEFT -99 /* value of parsenleft when EOF pushed back */
66	#define IBUFSIZ (BUFSIZ + 1)
67
68	MKINIT
69	struct strpush {
70	struct strpush prev; / preceding string on stack */
71	char *prevstring;
72	int prevnleft;
73	struct alias ap; / if push was associated with an alias */
74	char string; / remember the string since it may change */
75	};
76
77	/*
78	* The parsefile structure pointed to by the global variable parsefile
79	* contains information about the current file being read.
80	*/
81
82	MKINIT
83	struct parsefile {
84	struct parsefile prev; / preceding file on stack */
85	int linno; /* current line */
86	int fd; /* file descriptor (or -1 if string) */
87	int nleft; /* number of chars left in this line */
88	int lleft; /* number of chars left in this buffer */
89	char nextc; / next char in buffer */
90	char buf; / input buffer */
91	struct strpush strpush; / for pushing strings at this level */
92	struct strpush basestrpush; /* so pushing one is fast */
93	};
94
95
96	int plinno = 1; /* input line number */
97	int parsenleft; /* copy of parsefile->nleft */
98	MKINIT int parselleft; /* copy of parsefile->lleft */
99	char parsenextc; / copy of parsefile->nextc */
100	MKINIT struct parsefile basepf; /* top level input file */
101	MKINIT char basebuf[IBUFSIZ]; /* buffer for top level input file */
102	struct parsefile parsefile = &basepf; / current input file */
103	int whichprompt; /* 1 == PS1, 2 == PS2 */
104
105	#ifndef SMALL
106	EditLine el; / cookie for editline package */
107	#endif
108
109	STATIC void pushfile(void);
110	static int preadfd(void);
111	static void setinputfd(int fd, int push);
112
113	#ifdef mkinit
114	INCLUDE <stdio.h>
115	INCLUDE "input.h"
116	INCLUDE "error.h"
117
118	INIT {
119	basepf.nextc = basepf.buf = basebuf;
120	}
121
122	RESET {
123	parselleft = parsenleft = 0; /* clear input buffer */
124	popallfiles();
125	}
126	#endif
127
128
129	/*
130	* Read a character from the script, returning PEOF on end of file.
131	* Nul characters in the input are silently discarded.
132	*/
133
134	int
135	pgetc(void)
136	{
137	return pgetc_macro();
138	}
139
140
141	/*
142	* Same as pgetc(), but ignores PEOA.
143	*/
144
145	int
146	pgetc2()
147	{
148	int c;
149	do {
150	c = pgetc_macro();
151	} while (c == PEOA);
152	return c;
153	}
154
155
156	static int
157	preadfd(void)
158	{
159	int nr;
160	char *buf = parsefile->buf;
161	parsenextc = buf;
162
163	retry:
164	#ifndef SMALL
165	if (parsefile->fd == 0 && el) {
166	static const char *rl_cp;
167	static int el_len;
168
169	if (rl_cp == NULL)
170	rl_cp = el_gets(el, &el_len);
171	if (rl_cp == NULL)
172	nr = 0;
173	else {
174	nr = el_len;
175	if (nr > IBUFSIZ - 1)
176	nr = IBUFSIZ - 1;
177	memcpy(buf, rl_cp, nr);
178	if (nr != el_len) {
179	el_len -= nr;
180	rl_cp += nr;
181	} else
182	rl_cp = 0;
183	}
184
185	} else
186	#endif
187
188	#ifdef HETIO
189	nr = hetio_read_input(parsefile->fd);
190	if (nr == -255)
191	#endif
192	nr = read(parsefile->fd, buf, IBUFSIZ - 1);
193
194
195	if (nr < 0) {
196	if (errno == EINTR)
197	goto retry;
198	if (parsefile->fd == 0 && errno == EWOULDBLOCK) {
199	int flags = fcntl(0, F_GETFL, 0);
200	if (flags >= 0 && flags & O_NONBLOCK) {
201	flags &=~ O_NONBLOCK;
202	if (fcntl(0, F_SETFL, flags) >= 0) {
203	out2str("sh: turning off NDELAY mode\n");
204	goto retry;
205	}
206	}
207	}
208	}
209	return nr;
210	}
211
212	/*
213	* Refill the input buffer and return the next input character:
214	*
215	* 1) If a string was pushed back on the input, pop it;
216	* 2) If an EOF was pushed back (parsenleft == EOF_NLEFT) or we are reading
217	* from a string so we can't refill the buffer, return EOF.
218	* 3) If the is more stuff in this buffer, use it else call read to fill it.
219	* 4) Process input up to the next newline, deleting nul characters.
220	*/
221
222	int
223	preadbuffer(void)
224	{
225	char *q;
226	int more;
227	#ifndef SMALL
228	int something;
229	#endif
230	char savec;
231
232	while (unlikely(parsefile->strpush)) {
233	if (
234	parsenleft == -1 && parsefile->strpush->ap &&
235	parsenextc[-1] != ' ' && parsenextc[-1] != '\t'
236	) {
237	return PEOA;
238	}
239	popstring();
240	if (--parsenleft >= 0)
241	return (signed char)*parsenextc++;
242	}
243	if (unlikely(parsenleft == EOF_NLEFT \|\| parsefile->buf == NULL))
244	return PEOF;
245	flushout(&output);
246	#ifdef FLUSHERR
247	flushout(&errout);
248	#endif
249
250	more = parselleft;
251	if (more <= 0) {
252	again:
253	if ((more = preadfd()) <= 0) {
254	parselleft = parsenleft = EOF_NLEFT;
255	return PEOF;
256	}
257	}
258
259	q = parsenextc;
260
261	/* delete nul characters */
262	#ifndef SMALL
263	something = 0;
264	#endif
265	for (;;) {
266	int c;
267
268	more--;
269	c = *q;
270
271	if (!c)
272	memmove(q, q + 1, more);
273	else {
274	q++;
275
276	if (c == '\n') {
277	parsenleft = q - parsenextc - 1;
278	break;
279	}
280
281	#ifndef SMALL
282	switch (c) {
283	default:
284	something = 1;
285	/* fall through */
286	case '\t':
287	case ' ':
288	break;
289	}
290	#endif
291	}
292
293	if (more <= 0) {
294	parsenleft = q - parsenextc - 1;
295	if (parsenleft < 0)
296	goto again;
297	break;
298	}
299	}
300	parselleft = more;
301
302	savec = *q;
303	*q = '\0';
304
305	#ifndef SMALL
306	if (parsefile->fd == 0 && hist && something) {
307	HistEvent he;
308	INTOFF;
309	history(hist, &he, whichprompt == 1? H_ENTER : H_APPEND,
310	parsenextc);
311	INTON;
312	}
313	#endif
314
315	if (vflag) {
316	out2str(parsenextc);
317	#ifdef FLUSHERR
318	flushout(out2);
319	#endif
320	}
321
322	*q = savec;
323
324	return (signed char)*parsenextc++;
325	}
326
327	/*
328	* Undo the last call to pgetc. Only one character may be pushed back.
329	* PEOF may be pushed back.
330	*/
331
332	void
333	pungetc(void)
334	{
335	parsenleft++;
336	parsenextc--;
337	}
338
339	/*
340	* Push a string back onto the input at this current parsefile level.
341	* We handle aliases this way.
342	*/
343	void
344	pushstring(char s, void ap)
345	{
346	struct strpush *sp;
347	size_t len;
348
349	len = strlen(s);
350	INTOFF;
351	/dprintf("** calling pushstring: %s, %d\n", s, len);*/
352	if (parsefile->strpush) {
353	sp = ckmalloc(sizeof (struct strpush));
354	sp->prev = parsefile->strpush;
355	parsefile->strpush = sp;
356	} else
357	sp = parsefile->strpush = &(parsefile->basestrpush);
358	sp->prevstring = parsenextc;
359	sp->prevnleft = parsenleft;
360	sp->ap = (struct alias *)ap;
361	if (ap) {
362	((struct alias *)ap)->flag \|= ALIASINUSE;
363	sp->string = s;
364	}
365	parsenextc = s;
366	parsenleft = len;
367	INTON;
368	}
369
370	void
371	popstring(void)
372	{
373	struct strpush *sp = parsefile->strpush;
374
375	INTOFF;
376	if (sp->ap) {
377	if (parsenextc[-1] == ' ' \|\| parsenextc[-1] == '\t') {
378	checkkwd \|= CHKALIAS;
379	}
380	if (sp->string != sp->ap->val) {
381	ckfree(sp->string);
382	}
383	sp->ap->flag &= ~ALIASINUSE;
384	if (sp->ap->flag & ALIASDEAD) {
385	unalias(sp->ap->name);
386	}
387	}
388	parsenextc = sp->prevstring;
389	parsenleft = sp->prevnleft;
390	/dprintf("** calling popstring: restoring to '%s'\n", parsenextc);*/
391	parsefile->strpush = sp->prev;
392	if (sp != &(parsefile->basestrpush))
393	ckfree(sp);
394	INTON;
395	}
396
397	/*
398	* Set the input to take input from a file. If push is set, push the
399	* old input onto the stack first.
400	*/
401
402	int
403	setinputfile(const char *fname, int flags)
404	{
405	int fd;
406
407	INTOFF;
408	if ((fd = open(fname, O_RDONLY)) < 0) {
409	if (flags & INPUT_NOFILE_OK)
410	goto out;
411	sh_error("Can't open %s", fname);
412	}
413	if (fd < 10)
414	fd = savefd(fd, fd);
415	setinputfd(fd, flags & INPUT_PUSH_FILE);
416	out:
417	INTON;
418	return fd;
419	}
420
421
422	/*
423	* Like setinputfile, but takes an open file descriptor. Call this with
424	* interrupts off.
425	*/
426
427	static void
428	setinputfd(int fd, int push)
429	{
430	if (push) {
431	pushfile();
432	parsefile->buf = 0;
433	}
434	parsefile->fd = fd;
435	if (parsefile->buf == NULL)
436	parsefile->buf = ckmalloc(IBUFSIZ);
437	parselleft = parsenleft = 0;
438	plinno = 1;
439	}
440
441
442	/*
443	* Like setinputfile, but takes input from a string.
444	*/
445
446	void
447	setinputstring(char *string)
448	{
449	INTOFF;
450	pushfile();
451	parsenextc = string;
452	parsenleft = strlen(string);
453	parsefile->buf = NULL;
454	plinno = 1;
455	INTON;
456	}
457
458
459
460	/*
461	* To handle the "." command, a stack of input files is used. Pushfile
462	* adds a new entry to the stack and popfile restores the previous level.
463	*/
464
465	STATIC void
466	pushfile(void)
467	{
468	struct parsefile *pf;
469
470	parsefile->nleft = parsenleft;
471	parsefile->lleft = parselleft;
472	parsefile->nextc = parsenextc;
473	parsefile->linno = plinno;
474	pf = (struct parsefile *)ckmalloc(sizeof (struct parsefile));
475	pf->prev = parsefile;
476	pf->fd = -1;
477	pf->strpush = NULL;
478	pf->basestrpush.prev = NULL;
479	parsefile = pf;
480	}
481
482
483	void
484	popfile(void)
485	{
486	struct parsefile *pf = parsefile;
487
488	INTOFF;
489	if (pf->fd >= 0)
490	close(pf->fd);
491	if (pf->buf)
492	ckfree(pf->buf);
493	while (pf->strpush)
494	popstring();
495	parsefile = pf->prev;
496	ckfree(pf);
497	parsenleft = parsefile->nleft;
498	parselleft = parsefile->lleft;
499	parsenextc = parsefile->nextc;
500	plinno = parsefile->linno;
501	INTON;
502	}
503
504
505	/*
506	* Return to top level.
507	*/
508
509	void
510	popallfiles(void)
511	{
512	while (parsefile != &basepf)
513	popfile();
514	}
515
516
517
518	/*
519	* Close the file(s) that the shell is reading commands from. Called
520	* after a fork is done.
521	*/
522
523	void
524	closescript(void)
525	{
526	popallfiles();
527	if (parsefile->fd > 0) {
528	close(parsefile->fd);
529	parsefile->fd = 0;
530	}
531	}
532
533
534	int lineno_inc(void)
535	{
536	int lineno = plinno++;
537
538	setvarint("LINENO", lineno, 0);
539	return lineno;
540	}