1 /*- 2 * Copyright (c) 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Kenneth Almquist. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 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. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)input.c 8.3 (Berkeley) 6/9/95 37 * $FreeBSD: src/bin/sh/input.c,v 1.14.2.2 2002/08/27 01:36:28 tjr Exp $ 38 * $DragonFly: src/bin/sh/input.c,v 1.6 2005/11/13 11:58:30 corecode Exp $ 39 */ 40 41 #include <stdio.h> /* defines BUFSIZ */ 42 #include <fcntl.h> 43 #include <errno.h> 44 #include <unistd.h> 45 #include <stdlib.h> 46 #include <string.h> 47 48 /* 49 * This file implements the input routines used by the parser. 50 */ 51 52 #include "shell.h" 53 #include "redir.h" 54 #include "syntax.h" 55 #include "input.h" 56 #include "output.h" 57 #include "options.h" 58 #include "memalloc.h" 59 #include "error.h" 60 #include "alias.h" 61 #include "parser.h" 62 #include "myhistedit.h" 63 #include "trap.h" 64 65 #define EOF_NLEFT -99 /* value of parsenleft when EOF pushed back */ 66 67 MKINIT 68 struct strpush { 69 struct strpush *prev; /* preceding string on stack */ 70 char *prevstring; 71 int prevnleft; 72 int prevlleft; 73 struct alias *ap; /* if push was associated with an alias */ 74 }; 75 76 /* 77 * The parsefile structure pointed to by the global variable parsefile 78 * contains information about the current file being read. 79 */ 80 81 MKINIT 82 struct parsefile { 83 struct parsefile *prev; /* preceding file on stack */ 84 int linno; /* current line */ 85 int fd; /* file descriptor (or -1 if string) */ 86 int nleft; /* number of chars left in this line */ 87 int lleft; /* number of lines left in this buffer */ 88 char *nextc; /* next char in buffer */ 89 char *buf; /* input buffer */ 90 struct strpush *strpush; /* for pushing strings at this level */ 91 struct strpush basestrpush; /* so pushing one is fast */ 92 }; 93 94 95 int plinno = 1; /* input line number */ 96 MKINIT int parsenleft; /* copy of parsefile->nleft */ 97 MKINIT int parselleft; /* copy of parsefile->lleft */ 98 char *parsenextc; /* copy of parsefile->nextc */ 99 MKINIT struct parsefile basepf; /* top level input file */ 100 char basebuf[BUFSIZ]; /* buffer for top level input file */ 101 STATIC struct parsefile *parsefile = &basepf; /* current input file */ 102 int init_editline = 0; /* editline library initialized? */ 103 int whichprompt; /* 1 == PS1, 2 == PS2 */ 104 105 EditLine *el; /* cookie for editline package */ 106 107 STATIC void pushfile(void); 108 static int preadfd(void); 109 110 #ifdef mkinit 111 INCLUDE "input.h" 112 INCLUDE "error.h" 113 114 INIT { 115 extern char basebuf[]; 116 117 basepf.nextc = basepf.buf = basebuf; 118 } 119 120 RESET { 121 if (exception != EXSHELLPROC) 122 parselleft = parsenleft = 0; /* clear input buffer */ 123 popallfiles(); 124 } 125 126 SHELLPROC { 127 popallfiles(); 128 } 129 #endif 130 131 132 /* 133 * Read a line from the script. 134 */ 135 136 char * 137 pfgets(char *line, int len) 138 { 139 char *p = line; 140 int nleft = len; 141 int c; 142 143 while (--nleft > 0) { 144 c = pgetc_macro(); 145 if (c == PEOF) { 146 if (p == line) 147 return NULL; 148 break; 149 } 150 *p++ = c; 151 if (c == '\n') 152 break; 153 } 154 *p = '\0'; 155 return line; 156 } 157 158 159 160 /* 161 * Read a character from the script, returning PEOF on end of file. 162 * Nul characters in the input are silently discarded. 163 */ 164 165 int 166 pgetc(void) 167 { 168 return pgetc_macro(); 169 } 170 171 172 static int 173 preadfd(void) 174 { 175 int nr; 176 parsenextc = parsefile->buf; 177 178 #ifndef NO_HISTORY 179 if (el != NULL && gotwinch) { 180 gotwinch = 0; 181 el_resize(el); 182 } 183 #endif 184 retry: 185 #ifndef NO_HISTORY 186 if (parsefile->fd == 0 && el) { 187 const char *rl_cp; 188 189 rl_cp = el_gets(el, &nr); 190 if (rl_cp == NULL) 191 nr = 0; 192 else { 193 /* XXX - BUFSIZE should redesign so not necessary */ 194 strcpy(parsenextc, rl_cp); 195 } 196 } else 197 #endif 198 nr = read(parsefile->fd, parsenextc, BUFSIZ - 1); 199 200 if (nr <= 0) { 201 if (nr < 0) { 202 if (errno == EINTR) 203 goto retry; 204 if (parsefile->fd == 0 && errno == EWOULDBLOCK) { 205 int flags = fcntl(0, F_GETFL, 0); 206 if (flags >= 0 && flags & O_NONBLOCK) { 207 flags &=~ O_NONBLOCK; 208 if (fcntl(0, F_SETFL, flags) >= 0) { 209 out2str("sh: turning off NDELAY mode\n"); 210 goto retry; 211 } 212 } 213 } 214 } 215 nr = -1; 216 } 217 return nr; 218 } 219 220 /* 221 * Refill the input buffer and return the next input character: 222 * 223 * 1) If a string was pushed back on the input, pop it; 224 * 2) If an EOF was pushed back (parsenleft == EOF_NLEFT) or we are reading 225 * from a string so we can't refill the buffer, return EOF. 226 * 3) If there is more in this buffer, use it else call read to fill it. 227 * 4) Process input up to the next newline, deleting nul characters. 228 */ 229 230 int 231 preadbuffer(void) 232 { 233 char *p, *q; 234 int more; 235 int something; 236 char savec; 237 238 if (parsefile->strpush) { 239 popstring(); 240 if (--parsenleft >= 0) 241 return (*parsenextc++); 242 } 243 if (parsenleft == EOF_NLEFT || parsefile->buf == NULL) 244 return PEOF; 245 flushout(&output); 246 flushout(&errout); 247 248 again: 249 if (parselleft <= 0) { 250 if ((parselleft = preadfd()) == -1) { 251 parselleft = parsenleft = EOF_NLEFT; 252 return PEOF; 253 } 254 } 255 256 q = p = parsenextc; 257 258 /* delete nul characters */ 259 something = 0; 260 for (more = 1; more;) { 261 switch (*p) { 262 case '\0': 263 p++; /* Skip nul */ 264 goto check; 265 266 case '\t': 267 case ' ': 268 break; 269 270 case '\n': 271 parsenleft = q - parsenextc; 272 more = 0; /* Stop processing here */ 273 break; 274 275 default: 276 something = 1; 277 break; 278 } 279 280 *q++ = *p++; 281 check: 282 if (--parselleft <= 0) { 283 parsenleft = q - parsenextc - 1; 284 if (parsenleft < 0) 285 goto again; 286 *q = '\0'; 287 more = 0; 288 } 289 } 290 291 savec = *q; 292 *q = '\0'; 293 294 #ifndef NO_HISTORY 295 if (parsefile->fd == 0 && hist && something) { 296 HistEvent he; 297 INTOFF; 298 history(hist, &he, whichprompt == 1 ? H_ENTER : H_APPEND, parsenextc); 299 INTON; 300 } 301 #endif 302 303 if (vflag) { 304 out2str(parsenextc); 305 flushout(out2); 306 } 307 308 *q = savec; 309 310 return *parsenextc++; 311 } 312 313 /* 314 * Undo the last call to pgetc. Only one character may be pushed back. 315 * PEOF may be pushed back. 316 */ 317 318 void 319 pungetc(void) 320 { 321 parsenleft++; 322 parsenextc--; 323 } 324 325 /* 326 * Push a string back onto the input at this current parsefile level. 327 * We handle aliases this way. 328 */ 329 void 330 pushstring(char *s, int len, void *ap) 331 { 332 struct strpush *sp; 333 334 INTOFF; 335 /*dprintf("*** calling pushstring: %s, %d\n", s, len);*/ 336 if (parsefile->strpush) { 337 sp = ckmalloc(sizeof (struct strpush)); 338 sp->prev = parsefile->strpush; 339 parsefile->strpush = sp; 340 } else 341 sp = parsefile->strpush = &(parsefile->basestrpush); 342 sp->prevstring = parsenextc; 343 sp->prevnleft = parsenleft; 344 sp->prevlleft = parselleft; 345 sp->ap = (struct alias *)ap; 346 if (ap) 347 ((struct alias *)ap)->flag |= ALIASINUSE; 348 parsenextc = s; 349 parsenleft = len; 350 INTON; 351 } 352 353 void 354 popstring(void) 355 { 356 struct strpush *sp = parsefile->strpush; 357 358 INTOFF; 359 parsenextc = sp->prevstring; 360 parsenleft = sp->prevnleft; 361 parselleft = sp->prevlleft; 362 /*dprintf("*** calling popstring: restoring to '%s'\n", parsenextc);*/ 363 if (sp->ap) 364 sp->ap->flag &= ~ALIASINUSE; 365 parsefile->strpush = sp->prev; 366 if (sp != &(parsefile->basestrpush)) 367 ckfree(sp); 368 INTON; 369 } 370 371 /* 372 * Set the input to take input from a file. If push is set, push the 373 * old input onto the stack first. 374 */ 375 376 void 377 setinputfile(const char *fname, int push) 378 { 379 int fd; 380 int fd2; 381 382 INTOFF; 383 if ((fd = open(fname, O_RDONLY)) < 0) 384 error("Can't open %s: %s", fname, strerror(errno)); 385 if (fd < 10) { 386 fd2 = copyfd(fd, 10); 387 close(fd); 388 if (fd2 < 0) 389 error("Out of file descriptors"); 390 fd = fd2; 391 } 392 setinputfd(fd, push); 393 INTON; 394 } 395 396 397 /* 398 * Like setinputfile, but takes an open file descriptor. Call this with 399 * interrupts off. 400 */ 401 402 void 403 setinputfd(int fd, int push) 404 { 405 fcntl(fd, F_SETFD, FD_CLOEXEC); 406 if (push) { 407 pushfile(); 408 parsefile->buf = ckmalloc(BUFSIZ); 409 } 410 if (parsefile->fd > 0) 411 close(parsefile->fd); 412 parsefile->fd = fd; 413 if (parsefile->buf == NULL) 414 parsefile->buf = ckmalloc(BUFSIZ); 415 parselleft = parsenleft = 0; 416 plinno = 1; 417 } 418 419 420 /* 421 * Like setinputfile, but takes input from a string. 422 */ 423 424 void 425 setinputstring(char *string, int push) 426 { 427 INTOFF; 428 if (push) 429 pushfile(); 430 parsenextc = string; 431 parselleft = parsenleft = strlen(string); 432 parsefile->buf = NULL; 433 plinno = 1; 434 INTON; 435 } 436 437 438 439 /* 440 * To handle the "." command, a stack of input files is used. Pushfile 441 * adds a new entry to the stack and popfile restores the previous level. 442 */ 443 444 STATIC void 445 pushfile(void) 446 { 447 struct parsefile *pf; 448 449 parsefile->nleft = parsenleft; 450 parsefile->lleft = parselleft; 451 parsefile->nextc = parsenextc; 452 parsefile->linno = plinno; 453 pf = (struct parsefile *)ckmalloc(sizeof (struct parsefile)); 454 pf->prev = parsefile; 455 pf->fd = -1; 456 pf->strpush = NULL; 457 pf->basestrpush.prev = NULL; 458 parsefile = pf; 459 } 460 461 462 void 463 popfile(void) 464 { 465 struct parsefile *pf = parsefile; 466 467 INTOFF; 468 if (pf->fd >= 0) 469 close(pf->fd); 470 if (pf->buf) 471 ckfree(pf->buf); 472 while (pf->strpush) 473 popstring(); 474 parsefile = pf->prev; 475 ckfree(pf); 476 parsenleft = parsefile->nleft; 477 parselleft = parsefile->lleft; 478 parsenextc = parsefile->nextc; 479 plinno = parsefile->linno; 480 INTON; 481 } 482 483 484 /* 485 * Return to top level. 486 */ 487 488 void 489 popallfiles(void) 490 { 491 while (parsefile != &basepf) 492 popfile(); 493 } 494 495 496 497 /* 498 * Close the file(s) that the shell is reading commands from. Called 499 * after a fork is done. 500 */ 501 502 void 503 closescript(void) 504 { 505 popallfiles(); 506 if (parsefile->fd > 0) { 507 close(parsefile->fd); 508 parsefile->fd = 0; 509 } 510 } 511