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 1.23 2006/04/29 10:29:10 stefanf Exp $ 38 * $DragonFly: src/bin/sh/input.c,v 1.8 2007/01/13 20:10:26 pavalos 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 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 MKINIT 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 <stdio.h> 112 INCLUDE "input.h" 113 INCLUDE "error.h" 114 115 INIT { 116 basepf.nextc = basepf.buf = basebuf; 117 } 118 119 RESET { 120 if (exception != EXSHELLPROC) 121 parselleft = parsenleft = 0; /* clear input buffer */ 122 popallfiles(); 123 } 124 125 SHELLPROC { 126 popallfiles(); 127 } 128 #endif 129 130 131 /* 132 * Read a line from the script. 133 */ 134 135 char * 136 pfgets(char *line, int len) 137 { 138 char *p = line; 139 int nleft = len; 140 int c; 141 142 while (--nleft > 0) { 143 c = pgetc_macro(); 144 if (c == PEOF) { 145 if (p == line) 146 return NULL; 147 break; 148 } 149 *p++ = c; 150 if (c == '\n') 151 break; 152 } 153 *p = '\0'; 154 return line; 155 } 156 157 158 159 /* 160 * Read a character from the script, returning PEOF on end of file. 161 * Nul characters in the input are silently discarded. 162 */ 163 164 int 165 pgetc(void) 166 { 167 return pgetc_macro(); 168 } 169 170 171 static int 172 preadfd(void) 173 { 174 int nr; 175 parsenextc = parsefile->buf; 176 177 #ifndef NO_HISTORY 178 if (el != NULL && gotwinch) { 179 gotwinch = 0; 180 el_resize(el); 181 } 182 #endif 183 retry: 184 #ifndef NO_HISTORY 185 if (parsefile->fd == 0 && el) { 186 static const char *rl_cp; 187 static int el_len; 188 189 if (rl_cp == NULL) 190 rl_cp = el_gets(el, &el_len); 191 if (rl_cp == NULL) 192 nr = 0; 193 else { 194 nr = el_len; 195 if (nr > BUFSIZ - 1) 196 nr = BUFSIZ - 1; 197 memcpy(parsenextc, rl_cp, nr); 198 if (nr != el_len) { 199 el_len -= nr; 200 rl_cp += nr; 201 } else 202 rl_cp = NULL; 203 } 204 } else 205 #endif 206 nr = read(parsefile->fd, parsenextc, BUFSIZ - 1); 207 208 if (nr <= 0) { 209 if (nr < 0) { 210 if (errno == EINTR) 211 goto retry; 212 if (parsefile->fd == 0 && errno == EWOULDBLOCK) { 213 int flags = fcntl(0, F_GETFL, 0); 214 if (flags >= 0 && flags & O_NONBLOCK) { 215 flags &=~ O_NONBLOCK; 216 if (fcntl(0, F_SETFL, flags) >= 0) { 217 out2str("sh: turning off NDELAY mode\n"); 218 goto retry; 219 } 220 } 221 } 222 } 223 nr = -1; 224 } 225 return nr; 226 } 227 228 /* 229 * Refill the input buffer and return the next input character: 230 * 231 * 1) If a string was pushed back on the input, pop it; 232 * 2) If an EOF was pushed back (parsenleft == EOF_NLEFT) or we are reading 233 * from a string so we can't refill the buffer, return EOF. 234 * 3) If there is more in this buffer, use it else call read to fill it. 235 * 4) Process input up to the next newline, deleting nul characters. 236 */ 237 238 int 239 preadbuffer(void) 240 { 241 char *p, *q; 242 int more; 243 int something; 244 char savec; 245 246 if (parsefile->strpush) { 247 popstring(); 248 if (--parsenleft >= 0) 249 return (*parsenextc++); 250 } 251 if (parsenleft == EOF_NLEFT || parsefile->buf == NULL) 252 return PEOF; 253 flushout(&output); 254 flushout(&errout); 255 256 again: 257 if (parselleft <= 0) { 258 if ((parselleft = preadfd()) == -1) { 259 parselleft = parsenleft = EOF_NLEFT; 260 return PEOF; 261 } 262 } 263 264 q = p = parsenextc; 265 266 /* delete nul characters */ 267 something = 0; 268 for (more = 1; more;) { 269 switch (*p) { 270 case '\0': 271 p++; /* Skip nul */ 272 goto check; 273 274 case '\t': 275 case ' ': 276 break; 277 278 case '\n': 279 parsenleft = q - parsenextc; 280 more = 0; /* Stop processing here */ 281 break; 282 283 default: 284 something = 1; 285 break; 286 } 287 288 *q++ = *p++; 289 check: 290 if (--parselleft <= 0) { 291 parsenleft = q - parsenextc - 1; 292 if (parsenleft < 0) 293 goto again; 294 *q = '\0'; 295 more = 0; 296 } 297 } 298 299 savec = *q; 300 *q = '\0'; 301 302 #ifndef NO_HISTORY 303 if (parsefile->fd == 0 && hist && something) { 304 HistEvent he; 305 INTOFF; 306 history(hist, &he, whichprompt == 1 ? H_ENTER : H_APPEND, parsenextc); 307 INTON; 308 } 309 #endif 310 311 if (vflag) { 312 out2str(parsenextc); 313 flushout(out2); 314 } 315 316 *q = savec; 317 318 return *parsenextc++; 319 } 320 321 /* 322 * Undo the last call to pgetc. Only one character may be pushed back. 323 * PEOF may be pushed back. 324 */ 325 326 void 327 pungetc(void) 328 { 329 parsenleft++; 330 parsenextc--; 331 } 332 333 /* 334 * Push a string back onto the input at this current parsefile level. 335 * We handle aliases this way. 336 */ 337 void 338 pushstring(char *s, int len, void *ap) 339 { 340 struct strpush *sp; 341 342 INTOFF; 343 /*dprintf("*** calling pushstring: %s, %d\n", s, len);*/ 344 if (parsefile->strpush) { 345 sp = ckmalloc(sizeof (struct strpush)); 346 sp->prev = parsefile->strpush; 347 parsefile->strpush = sp; 348 } else 349 sp = parsefile->strpush = &(parsefile->basestrpush); 350 sp->prevstring = parsenextc; 351 sp->prevnleft = parsenleft; 352 sp->prevlleft = parselleft; 353 sp->ap = (struct alias *)ap; 354 if (ap) 355 ((struct alias *)ap)->flag |= ALIASINUSE; 356 parsenextc = s; 357 parsenleft = len; 358 INTON; 359 } 360 361 void 362 popstring(void) 363 { 364 struct strpush *sp = parsefile->strpush; 365 366 INTOFF; 367 parsenextc = sp->prevstring; 368 parsenleft = sp->prevnleft; 369 parselleft = sp->prevlleft; 370 /*dprintf("*** calling popstring: restoring to '%s'\n", parsenextc);*/ 371 if (sp->ap) 372 sp->ap->flag &= ~ALIASINUSE; 373 parsefile->strpush = sp->prev; 374 if (sp != &(parsefile->basestrpush)) 375 ckfree(sp); 376 INTON; 377 } 378 379 /* 380 * Set the input to take input from a file. If push is set, push the 381 * old input onto the stack first. 382 */ 383 384 void 385 setinputfile(const char *fname, int push) 386 { 387 int fd; 388 int fd2; 389 390 INTOFF; 391 if ((fd = open(fname, O_RDONLY)) < 0) 392 error("Can't open %s: %s", fname, strerror(errno)); 393 if (fd < 10) { 394 fd2 = fcntl(fd, F_DUPFD, 10); 395 close(fd); 396 if (fd2 < 0) 397 error("Out of file descriptors"); 398 fd = fd2; 399 } 400 setinputfd(fd, push); 401 INTON; 402 } 403 404 405 /* 406 * Like setinputfile, but takes an open file descriptor. Call this with 407 * interrupts off. 408 */ 409 410 void 411 setinputfd(int fd, int push) 412 { 413 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(char *string, int push) 434 { 435 INTOFF; 436 if (push) 437 pushfile(); 438 parsenextc = string; 439 parselleft = parsenleft = strlen(string); 440 parsefile->buf = NULL; 441 plinno = 1; 442 INTON; 443 } 444 445 446 447 /* 448 * To handle the "." command, a stack of input files is used. Pushfile 449 * adds a new entry to the stack and popfile restores the previous level. 450 */ 451 452 STATIC void 453 pushfile(void) 454 { 455 struct parsefile *pf; 456 457 parsefile->nleft = parsenleft; 458 parsefile->lleft = parselleft; 459 parsefile->nextc = parsenextc; 460 parsefile->linno = plinno; 461 pf = (struct parsefile *)ckmalloc(sizeof (struct parsefile)); 462 pf->prev = parsefile; 463 pf->fd = -1; 464 pf->strpush = NULL; 465 pf->basestrpush.prev = NULL; 466 parsefile = pf; 467 } 468 469 470 void 471 popfile(void) 472 { 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(void) 498 { 499 while (parsefile != &basepf) 500 popfile(); 501 } 502 503 504 505 /* 506 * Close the file(s) that the shell is reading commands from. Called 507 * after a fork is done. 508 */ 509 510 void 511 closescript(void) 512 { 513 popallfiles(); 514 if (parsefile->fd > 0) { 515 close(parsefile->fd); 516 parsefile->fd = 0; 517 } 518 } 519