1 /* $NetBSD: input.c,v 1.27 1997/07/04 21:02:03 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 1991, 1993 5 * The Regents of the University of California. 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. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 */ 38 39 #include <sys/cdefs.h> 40 #ifndef lint 41 #if 0 42 static char sccsid[] = "@(#)input.c 8.3 (Berkeley) 6/9/95"; 43 #else 44 __RCSID("$NetBSD: input.c,v 1.27 1997/07/04 21:02:03 christos Exp $"); 45 #endif 46 #endif /* not lint */ 47 48 #include <stdio.h> /* defines BUFSIZ */ 49 #include <fcntl.h> 50 #include <errno.h> 51 #include <unistd.h> 52 #include <stdlib.h> 53 #include <string.h> 54 55 /* 56 * This file implements the input routines used by the parser. 57 */ 58 59 #include "shell.h" 60 #include "redir.h" 61 #include "syntax.h" 62 #include "input.h" 63 #include "output.h" 64 #include "options.h" 65 #include "memalloc.h" 66 #include "error.h" 67 #include "alias.h" 68 #include "parser.h" 69 #include "myhistedit.h" 70 71 #define EOF_NLEFT -99 /* value of parsenleft when EOF pushed back */ 72 73 MKINIT 74 struct strpush { 75 struct strpush *prev; /* preceding string on stack */ 76 char *prevstring; 77 int prevnleft; 78 int prevlleft; 79 struct alias *ap; /* if push was associated with an alias */ 80 }; 81 82 /* 83 * The parsefile structure pointed to by the global variable parsefile 84 * contains information about the current file being read. 85 */ 86 87 MKINIT 88 struct parsefile { 89 struct parsefile *prev; /* preceding file on stack */ 90 int linno; /* current line */ 91 int fd; /* file descriptor (or -1 if string) */ 92 int nleft; /* number of chars left in this line */ 93 int lleft; /* number of chars left in this buffer */ 94 char *nextc; /* next char in buffer */ 95 char *buf; /* input buffer */ 96 struct strpush *strpush; /* for pushing strings at this level */ 97 struct strpush basestrpush; /* so pushing one is fast */ 98 }; 99 100 101 int plinno = 1; /* input line number */ 102 MKINIT int parsenleft; /* copy of parsefile->nleft */ 103 MKINIT int parselleft; /* copy of parsefile->lleft */ 104 char *parsenextc; /* copy of parsefile->nextc */ 105 MKINIT struct parsefile basepf; /* top level input file */ 106 char basebuf[BUFSIZ]; /* buffer for top level input file */ 107 struct parsefile *parsefile = &basepf; /* current input file */ 108 int init_editline = 0; /* editline library initialized? */ 109 int whichprompt; /* 1 == PS1, 2 == PS2 */ 110 111 EditLine *el; /* cookie for editline package */ 112 113 STATIC void pushfile __P((void)); 114 static int preadfd __P((void)); 115 116 #ifdef mkinit 117 INCLUDE "input.h" 118 INCLUDE "error.h" 119 120 INIT { 121 extern char basebuf[]; 122 123 basepf.nextc = basepf.buf = basebuf; 124 } 125 126 RESET { 127 if (exception != EXSHELLPROC) 128 parselleft = parsenleft = 0; /* clear input buffer */ 129 popallfiles(); 130 } 131 132 SHELLPROC { 133 popallfiles(); 134 } 135 #endif 136 137 138 /* 139 * Read a line from the script. 140 */ 141 142 char * 143 pfgets(line, len) 144 char *line; 145 int len; 146 { 147 char *p = line; 148 int nleft = len; 149 int c; 150 151 while (--nleft > 0) { 152 c = pgetc_macro(); 153 if (c == PEOF) { 154 if (p == line) 155 return NULL; 156 break; 157 } 158 *p++ = c; 159 if (c == '\n') 160 break; 161 } 162 *p = '\0'; 163 return line; 164 } 165 166 167 168 /* 169 * Read a character from the script, returning PEOF on end of file. 170 * Nul characters in the input are silently discarded. 171 */ 172 173 int 174 pgetc() 175 { 176 return pgetc_macro(); 177 } 178 179 180 static int 181 preadfd() 182 { 183 int nr; 184 parsenextc = parsefile->buf; 185 186 retry: 187 #ifndef SMALL 188 if (parsefile->fd == 0 && el) { 189 const char *rl_cp; 190 191 rl_cp = el_gets(el, &nr); 192 if (rl_cp == NULL) 193 nr = 0; 194 else { 195 /* XXX - BUFSIZE should redesign so not necessary */ 196 (void) strcpy(parsenextc, rl_cp); 197 } 198 } else 199 #endif 200 nr = read(parsefile->fd, parsenextc, BUFSIZ - 1); 201 202 203 if (nr <= 0) { 204 if (nr < 0) { 205 if (errno == EINTR) 206 goto retry; 207 if (parsefile->fd == 0 && errno == EWOULDBLOCK) { 208 int flags = fcntl(0, F_GETFL, 0); 209 if (flags >= 0 && flags & O_NONBLOCK) { 210 flags &=~ O_NONBLOCK; 211 if (fcntl(0, F_SETFL, flags) >= 0) { 212 out2str("sh: turning off NDELAY mode\n"); 213 goto retry; 214 } 215 } 216 } 217 } 218 nr = -1; 219 } 220 return nr; 221 } 222 223 /* 224 * Refill the input buffer and return the next input character: 225 * 226 * 1) If a string was pushed back on the input, pop it; 227 * 2) If an EOF was pushed back (parsenleft == EOF_NLEFT) or we are reading 228 * from a string so we can't refill the buffer, return EOF. 229 * 3) If the is more stuff in this buffer, use it else call read to fill it. 230 * 4) Process input up to the next newline, deleting nul characters. 231 */ 232 233 int 234 preadbuffer() 235 { 236 char *p, *q; 237 int more; 238 int something; 239 extern EditLine *el; 240 char savec; 241 242 if (parsefile->strpush) { 243 popstring(); 244 if (--parsenleft >= 0) 245 return (*parsenextc++); 246 } 247 if (parsenleft == EOF_NLEFT || parsefile->buf == NULL) 248 return PEOF; 249 flushout(&output); 250 flushout(&errout); 251 252 again: 253 if (parselleft <= 0) { 254 if ((parselleft = preadfd()) == -1) { 255 parselleft = parsenleft = EOF_NLEFT; 256 return PEOF; 257 } 258 } 259 260 q = p = parsenextc; 261 262 /* delete nul characters */ 263 something = 0; 264 for (more = 1; more;) { 265 switch (*p) { 266 case '\0': 267 p++; /* Skip nul */ 268 goto check; 269 270 case '\t': 271 case ' ': 272 break; 273 274 case '\n': 275 parsenleft = q - parsenextc; 276 more = 0; /* Stop processing here */ 277 break; 278 279 default: 280 something = 1; 281 break; 282 } 283 284 *q++ = *p++; 285 check: 286 if (--parselleft <= 0) { 287 parsenleft = q - parsenextc - 1; 288 if (parsenleft < 0) 289 goto again; 290 *q = '\0'; 291 more = 0; 292 } 293 } 294 295 savec = *q; 296 *q = '\0'; 297 298 #ifndef SMALL 299 if (parsefile->fd == 0 && hist && something) { 300 INTOFF; 301 history(hist, whichprompt == 1 ? H_ENTER : H_ADD, parsenextc); 302 INTON; 303 } 304 #endif 305 306 if (vflag) { 307 out2str(parsenextc); 308 flushout(out2); 309 } 310 311 *q = savec; 312 313 return *parsenextc++; 314 } 315 316 /* 317 * Undo the last call to pgetc. Only one character may be pushed back. 318 * PEOF may be pushed back. 319 */ 320 321 void 322 pungetc() { 323 parsenleft++; 324 parsenextc--; 325 } 326 327 /* 328 * Push a string back onto the input at this current parsefile level. 329 * We handle aliases this way. 330 */ 331 void 332 pushstring(s, len, ap) 333 char *s; 334 int len; 335 void *ap; 336 { 337 struct strpush *sp; 338 339 INTOFF; 340 /*dprintf("*** calling pushstring: %s, %d\n", s, len);*/ 341 if (parsefile->strpush) { 342 sp = ckmalloc(sizeof (struct strpush)); 343 sp->prev = parsefile->strpush; 344 parsefile->strpush = sp; 345 } else 346 sp = parsefile->strpush = &(parsefile->basestrpush); 347 sp->prevstring = parsenextc; 348 sp->prevnleft = parsenleft; 349 sp->prevlleft = parselleft; 350 sp->ap = (struct alias *)ap; 351 if (ap) 352 ((struct alias *)ap)->flag |= ALIASINUSE; 353 parsenextc = s; 354 parsenleft = len; 355 INTON; 356 } 357 358 void 359 popstring() 360 { 361 struct strpush *sp = parsefile->strpush; 362 363 INTOFF; 364 parsenextc = sp->prevstring; 365 parsenleft = sp->prevnleft; 366 parselleft = sp->prevlleft; 367 /*dprintf("*** calling popstring: restoring to '%s'\n", parsenextc);*/ 368 if (sp->ap) 369 sp->ap->flag &= ~ALIASINUSE; 370 parsefile->strpush = sp->prev; 371 if (sp != &(parsefile->basestrpush)) 372 ckfree(sp); 373 INTON; 374 } 375 376 /* 377 * Set the input to take input from a file. If push is set, push the 378 * old input onto the stack first. 379 */ 380 381 void 382 setinputfile(fname, push) 383 char *fname; 384 int push; 385 { 386 int fd; 387 int fd2; 388 389 INTOFF; 390 if ((fd = open(fname, O_RDONLY)) < 0) 391 error("Can't open %s", fname); 392 if (fd < 10) { 393 fd2 = copyfd(fd, 10); 394 close(fd); 395 if (fd2 < 0) 396 error("Out of file descriptors"); 397 fd = fd2; 398 } 399 setinputfd(fd, push); 400 INTON; 401 } 402 403 404 /* 405 * Like setinputfile, but takes an open file descriptor. Call this with 406 * interrupts off. 407 */ 408 409 void 410 setinputfd(fd, push) 411 int fd, push; 412 { 413 (void) fcntl(fd, F_SETFD, FD_CLOEXEC); 414 if (push) { 415 pushfile(); 416 parsefile->buf = ckmalloc(BUFSIZ); 417 } 418 if (parsefile->fd > 0) 419 close(parsefile->fd); 420 parsefile->fd = fd; 421 if (parsefile->buf == NULL) 422 parsefile->buf = ckmalloc(BUFSIZ); 423 parselleft = parsenleft = 0; 424 plinno = 1; 425 } 426 427 428 /* 429 * Like setinputfile, but takes input from a string. 430 */ 431 432 void 433 setinputstring(string, push) 434 char *string; 435 int push; 436 { 437 INTOFF; 438 if (push) 439 pushfile(); 440 parsenextc = string; 441 parselleft = parsenleft = strlen(string); 442 parsefile->buf = NULL; 443 plinno = 1; 444 INTON; 445 } 446 447 448 449 /* 450 * To handle the "." command, a stack of input files is used. Pushfile 451 * adds a new entry to the stack and popfile restores the previous level. 452 */ 453 454 STATIC void 455 pushfile() { 456 struct parsefile *pf; 457 458 parsefile->nleft = parsenleft; 459 parsefile->lleft = parselleft; 460 parsefile->nextc = parsenextc; 461 parsefile->linno = plinno; 462 pf = (struct parsefile *)ckmalloc(sizeof (struct parsefile)); 463 pf->prev = parsefile; 464 pf->fd = -1; 465 pf->strpush = NULL; 466 pf->basestrpush.prev = NULL; 467 parsefile = pf; 468 } 469 470 471 void 472 popfile() { 473 struct parsefile *pf = parsefile; 474 475 INTOFF; 476 if (pf->fd >= 0) 477 close(pf->fd); 478 if (pf->buf) 479 ckfree(pf->buf); 480 while (pf->strpush) 481 popstring(); 482 parsefile = pf->prev; 483 ckfree(pf); 484 parsenleft = parsefile->nleft; 485 parselleft = parsefile->lleft; 486 parsenextc = parsefile->nextc; 487 plinno = parsefile->linno; 488 INTON; 489 } 490 491 492 /* 493 * Return to top level. 494 */ 495 496 void 497 popallfiles() { 498 while (parsefile != &basepf) 499 popfile(); 500 } 501 502 503 504 /* 505 * Close the file(s) that the shell is reading commands from. Called 506 * after a fork is done. 507 */ 508 509 void 510 closescript() { 511 popallfiles(); 512 if (parsefile->fd > 0) { 513 close(parsefile->fd); 514 parsefile->fd = 0; 515 } 516 } 517