1 /* $NetBSD: input.c,v 1.19 1995/10/19 04:14:37 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 #ifndef lint 40 #if 0 41 static char sccsid[] = "@(#)input.c 8.3 (Berkeley) 6/9/95"; 42 #else 43 static char rcsid[] = "$NetBSD: input.c,v 1.19 1995/10/19 04:14:37 christos Exp $"; 44 #endif 45 #endif /* not lint */ 46 47 #include <stdio.h> /* defines BUFSIZ */ 48 #include <fcntl.h> 49 #include <errno.h> 50 #include <unistd.h> 51 #include <stdlib.h> 52 #include <string.h> 53 54 /* 55 * This file implements the input routines used by the parser. 56 */ 57 58 #include "shell.h" 59 #include "redir.h" 60 #include "syntax.h" 61 #include "input.h" 62 #include "output.h" 63 #include "options.h" 64 #include "memalloc.h" 65 #include "error.h" 66 #include "alias.h" 67 #include "parser.h" 68 #include "myhistedit.h" 69 70 #define EOF_NLEFT -99 /* value of parsenleft when EOF pushed back */ 71 72 MKINIT 73 struct strpush { 74 struct strpush *prev; /* preceding string on stack */ 75 char *prevstring; 76 int prevnleft; 77 int prevlleft; 78 struct alias *ap; /* if push was associated with an alias */ 79 }; 80 81 /* 82 * The parsefile structure pointed to by the global variable parsefile 83 * contains information about the current file being read. 84 */ 85 86 MKINIT 87 struct parsefile { 88 struct parsefile *prev; /* preceding file on stack */ 89 int linno; /* current line */ 90 int fd; /* file descriptor (or -1 if string) */ 91 int nleft; /* number of chars left in this line */ 92 int lleft; /* number of chars left in this buffer */ 93 char *nextc; /* next char in buffer */ 94 char *buf; /* input buffer */ 95 struct strpush *strpush; /* for pushing strings at this level */ 96 struct strpush basestrpush; /* so pushing one is fast */ 97 }; 98 99 100 int plinno = 1; /* input line number */ 101 MKINIT int parsenleft; /* copy of parsefile->nleft */ 102 MKINIT int parselleft; /* copy of parsefile->lleft */ 103 char *parsenextc; /* copy of parsefile->nextc */ 104 MKINIT struct parsefile basepf; /* top level input file */ 105 char basebuf[BUFSIZ]; /* buffer for top level input file */ 106 struct parsefile *parsefile = &basepf; /* current input file */ 107 int init_editline = 0; /* editline library initialized? */ 108 int whichprompt; /* 1 == PS1, 2 == PS2 */ 109 110 EditLine *el; /* cookie for editline package */ 111 112 STATIC void pushfile __P((void)); 113 static int pread __P((void)); 114 115 #ifdef mkinit 116 INCLUDE "input.h" 117 INCLUDE "error.h" 118 119 INIT { 120 extern char basebuf[]; 121 122 basepf.nextc = basepf.buf = basebuf; 123 } 124 125 RESET { 126 if (exception != EXSHELLPROC) 127 parselleft = parsenleft = 0; /* clear input buffer */ 128 popallfiles(); 129 } 130 131 SHELLPROC { 132 popallfiles(); 133 } 134 #endif 135 136 137 /* 138 * Read a line from the script. 139 */ 140 141 char * 142 pfgets(line, len) 143 char *line; 144 int len; 145 { 146 register char *p = line; 147 int nleft = len; 148 int c; 149 150 while (--nleft > 0) { 151 c = pgetc_macro(); 152 if (c == PEOF) { 153 if (p == line) 154 return NULL; 155 break; 156 } 157 *p++ = c; 158 if (c == '\n') 159 break; 160 } 161 *p = '\0'; 162 return line; 163 } 164 165 166 167 /* 168 * Read a character from the script, returning PEOF on end of file. 169 * Nul characters in the input are silently discarded. 170 */ 171 172 int 173 pgetc() 174 { 175 return pgetc_macro(); 176 } 177 178 179 static int 180 pread() 181 { 182 int nr; 183 parsenextc = parsefile->buf; 184 185 retry: 186 if (parsefile->fd == 0 && el) { 187 const char *rl_cp; 188 int len; 189 190 rl_cp = el_gets(el, &nr); 191 if (rl_cp == NULL) 192 nr = 0; 193 else { 194 /* XXX - BUFSIZE should redesign so not necessary */ 195 (void) strcpy(parsenextc, rl_cp); 196 } 197 } else { 198 nr = read(parsefile->fd, parsenextc, BUFSIZ - 1); 199 } 200 201 if (nr <= 0) { 202 if (nr < 0) { 203 if (errno == EINTR) 204 goto retry; 205 if (parsefile->fd == 0 && errno == EWOULDBLOCK) { 206 int flags = fcntl(0, F_GETFL, 0); 207 if (flags >= 0 && flags & O_NONBLOCK) { 208 flags &=~ O_NONBLOCK; 209 if (fcntl(0, F_SETFL, flags) >= 0) { 210 out2str("sh: turning off NDELAY mode\n"); 211 goto retry; 212 } 213 } 214 } 215 } 216 nr = -1; 217 } 218 return nr; 219 } 220 221 /* 222 * Refill the input buffer and return the next input character: 223 * 224 * 1) If a string was pushed back on the input, pop it; 225 * 2) If an EOF was pushed back (parsenleft == EOF_NLEFT) or we are reading 226 * from a string so we can't refill the buffer, return EOF. 227 * 3) If the is more stuff in this buffer, use it else call read to fill it. 228 * 4) Process input up to the next newline, deleting nul characters. 229 */ 230 231 int 232 preadbuffer() 233 { 234 char *p, *q; 235 int more; 236 int something; 237 extern EditLine *el; 238 char savec; 239 240 if (parsefile->strpush) { 241 popstring(); 242 if (--parsenleft >= 0) 243 return (*parsenextc++); 244 } 245 if (parsenleft == EOF_NLEFT || parsefile->buf == NULL) 246 return PEOF; 247 flushout(&output); 248 flushout(&errout); 249 250 again: 251 if (parselleft <= 0) { 252 if ((parselleft = pread()) == -1) { 253 parselleft = parsenleft = EOF_NLEFT; 254 return PEOF; 255 } 256 } 257 258 q = p = parsenextc; 259 260 /* delete nul characters */ 261 something = 0; 262 for (more = 1; more;) { 263 switch (*p) { 264 case '\0': 265 p++; /* Skip nul */ 266 goto check; 267 268 case '\t': 269 case ' ': 270 break; 271 272 case '\n': 273 parsenleft = q - parsenextc; 274 more = 0; /* Stop processing here */ 275 break; 276 277 default: 278 something = 1; 279 break; 280 } 281 282 *q++ = *p++; 283 check: 284 if (--parselleft <= 0) { 285 parsenleft = q - parsenextc - 1; 286 if (parsenleft < 0) 287 goto again; 288 *q = '\0'; 289 more = 0; 290 } 291 } 292 293 savec = *q; 294 *q = '\0'; 295 296 #ifndef NO_HISTORY 297 if (parsefile->fd == 0 && hist && something) { 298 INTOFF; 299 history(hist, whichprompt == 1 ? H_ENTER : H_ADD, parsenextc); 300 INTON; 301 } 302 #endif 303 304 if (vflag) { 305 out2str(parsenextc); 306 flushout(out2); 307 } 308 309 *q = savec; 310 311 return *parsenextc++; 312 } 313 314 /* 315 * Undo the last call to pgetc. Only one character may be pushed back. 316 * PEOF may be pushed back. 317 */ 318 319 void 320 pungetc() { 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(s, len, ap) 331 char *s; 332 int len; 333 void *ap; 334 { 335 struct strpush *sp; 336 337 INTOFF; 338 /*dprintf("*** calling pushstring: %s, %d\n", s, len);*/ 339 if (parsefile->strpush) { 340 sp = ckmalloc(sizeof (struct strpush)); 341 sp->prev = parsefile->strpush; 342 parsefile->strpush = sp; 343 } else 344 sp = parsefile->strpush = &(parsefile->basestrpush); 345 sp->prevstring = parsenextc; 346 sp->prevnleft = parsenleft; 347 sp->prevlleft = parselleft; 348 sp->ap = (struct alias *)ap; 349 if (ap) 350 ((struct alias *)ap)->flag |= ALIASINUSE; 351 parsenextc = s; 352 parsenleft = len; 353 INTON; 354 } 355 356 void 357 popstring() 358 { 359 struct strpush *sp = parsefile->strpush; 360 361 INTOFF; 362 parsenextc = sp->prevstring; 363 parsenleft = sp->prevnleft; 364 parselleft = sp->prevlleft; 365 /*dprintf("*** calling popstring: restoring to '%s'\n", parsenextc);*/ 366 if (sp->ap) 367 sp->ap->flag &= ~ALIASINUSE; 368 parsefile->strpush = sp->prev; 369 if (sp != &(parsefile->basestrpush)) 370 ckfree(sp); 371 INTON; 372 } 373 374 /* 375 * Set the input to take input from a file. If push is set, push the 376 * old input onto the stack first. 377 */ 378 379 void 380 setinputfile(fname, push) 381 char *fname; 382 int push; 383 { 384 int fd; 385 int fd2; 386 387 INTOFF; 388 if ((fd = open(fname, O_RDONLY)) < 0) 389 error("Can't open %s", fname); 390 if (fd < 10) { 391 fd2 = copyfd(fd, 10); 392 close(fd); 393 if (fd2 < 0) 394 error("Out of file descriptors"); 395 fd = fd2; 396 } 397 setinputfd(fd, push); 398 INTON; 399 } 400 401 402 /* 403 * Like setinputfile, but takes an open file descriptor. Call this with 404 * interrupts off. 405 */ 406 407 void 408 setinputfd(fd, push) 409 int fd, push; 410 { 411 if (push) { 412 pushfile(); 413 parsefile->buf = ckmalloc(BUFSIZ); 414 } 415 if (parsefile->fd > 0) 416 close(parsefile->fd); 417 parsefile->fd = fd; 418 if (parsefile->buf == NULL) 419 parsefile->buf = ckmalloc(BUFSIZ); 420 parselleft = parsenleft = 0; 421 plinno = 1; 422 } 423 424 425 /* 426 * Like setinputfile, but takes input from a string. 427 */ 428 429 void 430 setinputstring(string, push) 431 char *string; 432 int push; 433 { 434 INTOFF; 435 if (push) 436 pushfile(); 437 parsenextc = string; 438 parselleft = parsenleft = strlen(string); 439 parsefile->buf = NULL; 440 plinno = 1; 441 INTON; 442 } 443 444 445 446 /* 447 * To handle the "." command, a stack of input files is used. Pushfile 448 * adds a new entry to the stack and popfile restores the previous level. 449 */ 450 451 STATIC void 452 pushfile() { 453 struct parsefile *pf; 454 455 parsefile->nleft = parsenleft; 456 parsefile->lleft = parselleft; 457 parsefile->nextc = parsenextc; 458 parsefile->linno = plinno; 459 pf = (struct parsefile *)ckmalloc(sizeof (struct parsefile)); 460 pf->prev = parsefile; 461 pf->fd = -1; 462 pf->strpush = NULL; 463 pf->basestrpush.prev = NULL; 464 parsefile = pf; 465 } 466 467 468 void 469 popfile() { 470 struct parsefile *pf = parsefile; 471 472 INTOFF; 473 if (pf->fd >= 0) 474 close(pf->fd); 475 if (pf->buf) 476 ckfree(pf->buf); 477 while (pf->strpush) 478 popstring(); 479 parsefile = pf->prev; 480 ckfree(pf); 481 parsenleft = parsefile->nleft; 482 parselleft = parsefile->lleft; 483 parsenextc = parsefile->nextc; 484 plinno = parsefile->linno; 485 INTON; 486 } 487 488 489 /* 490 * Return to top level. 491 */ 492 493 void 494 popallfiles() { 495 while (parsefile != &basepf) 496 popfile(); 497 } 498 499 500 501 /* 502 * Close the file(s) that the shell is reading commands from. Called 503 * after a fork is done. 504 */ 505 506 void 507 closescript() { 508 popallfiles(); 509 if (parsefile->fd > 0) { 510 close(parsefile->fd); 511 parsefile->fd = 0; 512 } 513 } 514