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
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9 * modification, are permitted provided that the following conditions
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13 * 2. Redistributions in binary form must reproduce the above copyright
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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
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20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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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 static void pushfile(void);
106 static int preadfd(void);
107 static void popstring(void);
113 parselleft = parsenleft = 0; /* clear input buffer */
119 * Read a character from the script, returning PEOF on end of file.
120 * Nul characters in the input are silently discarded.
126 return pgetc_macro();
134 parsenextc = parsefile->buf;
138 if (parsefile->fd == 0 && el) {
139 static const char *rl_cp;
144 rl_cp = el_gets(el, &el_len);
147 nr = el_len == 0 ? 0 : -1;
152 memcpy(parsefile->buf, rl_cp, nr);
161 nr = read(parsefile->fd, parsefile->buf, BUFSIZ);
167 if (parsefile->fd == 0 && errno == EWOULDBLOCK) {
168 int flags = fcntl(0, F_GETFL, 0);
169 if (flags >= 0 && flags & O_NONBLOCK) {
170 flags &=~ O_NONBLOCK;
171 if (fcntl(0, F_SETFL, flags) >= 0) {
172 out2fmt_flush("sh: turning off NDELAY mode\n");
184 * Refill the input buffer and return the next input character:
186 * 1) If a string was pushed back on the input, pop it;
187 * 2) If an EOF was pushed back (parsenleft == EOF_NLEFT) or we are reading
188 * from a string so we can't refill the buffer, return EOF.
189 * 3) If there is more in this buffer, use it else call read to fill it.
190 * 4) Process input up to the next newline, deleting nul characters.
196 char *p, *q, *r, *end;
199 while (parsefile->strpush) {
201 * Add a space to the end of an alias to ensure that the
202 * alias remains in use while parsing its last word.
203 * This avoids alias recursions.
205 if (parsenleft == -1 && parsefile->strpush->ap != NULL)
208 if (--parsenleft >= 0)
209 return (*parsenextc++);
211 if (parsenleft == EOF_NLEFT || parsefile->buf == NULL)
215 if (parselleft <= 0) {
216 if ((parselleft = preadfd()) == -1) {
217 parselleft = parsenleft = EOF_NLEFT;
222 p = parsefile->buf + (parsenextc - parsefile->buf);
223 end = p + parselleft;
225 q = strchrnul(p, '\n');
226 if (q != end && *q == '\0') {
227 /* delete nul characters */
228 for (r = q; q != end; q++) {
232 parselleft -= end - r;
235 end = p + parselleft;
237 q = strchrnul(p, '\n');
240 parsenleft = parselleft;
242 } else /* *q == '\n' */ {
244 parsenleft = q - parsenextc;
245 parselleft -= parsenleft;
253 if (parsefile->fd == 0 && hist &&
254 parsenextc[strspn(parsenextc, " \t\n")] != '\0') {
257 history(hist, &he, whichprompt == 1 ? H_ENTER : H_ADD,
270 return *parsenextc++;
274 * Returns if we are certain we are at EOF. Does not cause any more input
275 * to be read from the outside world.
283 if (parsefile->strpush)
285 if (parsenleft == EOF_NLEFT || parsefile->buf == NULL)
291 * Undo the last call to pgetc. Only one character may be pushed back.
292 * PEOF may be pushed back.
303 * Push a string back onto the input at this current parsefile level.
304 * We handle aliases this way.
307 pushstring(const char *s, int len, struct alias *ap)
312 /*out2fmt_flush("*** calling pushstring: %s, %d\n", s, len);*/
313 if (parsefile->strpush) {
314 sp = ckmalloc(sizeof (struct strpush));
315 sp->prev = parsefile->strpush;
316 parsefile->strpush = sp;
318 sp = parsefile->strpush = &(parsefile->basestrpush);
319 sp->prevstring = parsenextc;
320 sp->prevnleft = parsenleft;
321 sp->prevlleft = parselleft;
324 ap->flag |= ALIASINUSE;
333 struct strpush *sp = parsefile->strpush;
337 if (parsenextc != sp->ap->val &&
338 (parsenextc[-1] == ' ' || parsenextc[-1] == '\t'))
340 sp->ap->flag &= ~ALIASINUSE;
342 parsenextc = sp->prevstring;
343 parsenleft = sp->prevnleft;
344 parselleft = sp->prevlleft;
345 /*out2fmt_flush("*** calling popstring: restoring to '%s'\n", parsenextc);*/
346 parsefile->strpush = sp->prev;
347 if (sp != &(parsefile->basestrpush))
353 * Set the input to take input from a file. If push is set, push the
354 * old input onto the stack first.
358 setinputfile(const char *fname, int push)
365 if ((fd = open(fname, O_RDONLY | O_CLOEXEC)) < 0) {
367 errorwithstatus(e == ENOENT || e == ENOTDIR ? 127 : 126,
368 "cannot open %s: %s", fname, strerror(e));
371 fd2 = fcntl(fd, F_DUPFD_CLOEXEC, 10);
374 error("Out of file descriptors");
377 setinputfd(fd, push);
383 * Like setinputfile, but takes an open file descriptor (which should have
384 * its FD_CLOEXEC flag already set). Call this with interrupts off.
388 setinputfd(int fd, int push)
392 parsefile->buf = ckmalloc(BUFSIZ + 1);
394 if (parsefile->fd > 0)
395 close(parsefile->fd);
397 if (parsefile->buf == NULL)
398 parsefile->buf = ckmalloc(BUFSIZ + 1);
399 parselleft = parsenleft = 0;
405 * Like setinputfile, but takes input from a string.
409 setinputstring(const char *string, int push)
415 parselleft = parsenleft = strlen(string);
416 parsefile->buf = NULL;
424 * To handle the "." command, a stack of input files is used. Pushfile
425 * adds a new entry to the stack and popfile restores the previous level.
431 struct parsefile *pf;
433 parsefile->nleft = parsenleft;
434 parsefile->lleft = parselleft;
435 parsefile->nextc = parsenextc;
436 parsefile->linno = plinno;
437 pf = (struct parsefile *)ckmalloc(sizeof (struct parsefile));
438 pf->prev = parsefile;
441 pf->basestrpush.prev = NULL;
449 struct parsefile *pf = parsefile;
458 parsefile = pf->prev;
460 parsenleft = parsefile->nleft;
461 parselleft = parsefile->lleft;
462 parsenextc = parsefile->nextc;
463 plinno = parsefile->linno;
469 * Return current file (to go back to it later using popfilesupto()).
480 * Pop files until the given file is on top again. Useful for regular
481 * builtins that read shell commands from files or strings.
482 * If the given file is not an active file, an error is raised.
486 popfilesupto(struct parsefile *file)
488 while (parsefile != file && parsefile != &basepf)
490 if (parsefile != file)
491 error("popfilesupto() misused");
495 * Return to top level.
501 while (parsefile != &basepf)
508 * Close the file(s) that the shell is reading commands from. Called
509 * after a fork is done.
516 if (parsefile->fd > 0) {
517 close(parsefile->fd);