1 /* $NetBSD: input.c,v 1.21 1996/11/02 18:26:03 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 #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 1.21 1996/11/02 18:26:03 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; 188 189 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 (void) strcpy(parsenextc, rl_cp); 195 } 196 } else { 197 nr = read(parsefile->fd, parsenextc, BUFSIZ - 1); 198 } 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 the is more stuff 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() 232 { 233 char *p, *q; 234 int more; 235 int something; 236 extern EditLine *el; 237 char savec; 238 239 if (parsefile->strpush) { 240 popstring(); 241 if (--parsenleft >= 0) 242 return (*parsenextc++); 243 } 244 if (parsenleft == EOF_NLEFT || parsefile->buf == NULL) 245 return PEOF; 246 flushout(&output); 247 flushout(&errout); 248 249 again: 250 if (parselleft <= 0) { 251 if ((parselleft = pread()) == -1) { 252 parselleft = parsenleft = EOF_NLEFT; 253 return PEOF; 254 } 255 } 256 257 q = p = parsenextc; 258 259 /* delete nul characters */ 260 something = 0; 261 for (more = 1; more;) { 262 switch (*p) { 263 case '\0': 264 p++; /* Skip nul */ 265 goto check; 266 267 case '\t': 268 case ' ': 269 break; 270 271 case '\n': 272 parsenleft = q - parsenextc; 273 more = 0; /* Stop processing here */ 274 break; 275 276 default: 277 something = 1; 278 break; 279 } 280 281 *q++ = *p++; 282 check: 283 if (--parselleft <= 0) { 284 parsenleft = q - parsenextc - 1; 285 if (parsenleft < 0) 286 goto again; 287 *q = '\0'; 288 more = 0; 289 } 290 } 291 292 savec = *q; 293 *q = '\0'; 294 295 #ifndef NO_HISTORY 296 if (parsefile->fd == 0 && hist && something) { 297 INTOFF; 298 history(hist, whichprompt == 1 ? H_ENTER : H_ADD, 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() { 320 parsenleft++; 321 parsenextc--; 322 } 323 324 /* 325 * Push a string back onto the input at this current parsefile level. 326 * We handle aliases this way. 327 */ 328 void 329 pushstring(s, len, ap) 330 char *s; 331 int len; 332 void *ap; 333 { 334 struct strpush *sp; 335 336 INTOFF; 337 /*dprintf("*** calling pushstring: %s, %d\n", s, len);*/ 338 if (parsefile->strpush) { 339 sp = ckmalloc(sizeof (struct strpush)); 340 sp->prev = parsefile->strpush; 341 parsefile->strpush = sp; 342 } else 343 sp = parsefile->strpush = &(parsefile->basestrpush); 344 sp->prevstring = parsenextc; 345 sp->prevnleft = parsenleft; 346 sp->prevlleft = parselleft; 347 sp->ap = (struct alias *)ap; 348 if (ap) 349 ((struct alias *)ap)->flag |= ALIASINUSE; 350 parsenextc = s; 351 parsenleft = len; 352 INTON; 353 } 354 355 void 356 popstring() 357 { 358 struct strpush *sp = parsefile->strpush; 359 360 INTOFF; 361 parsenextc = sp->prevstring; 362 parsenleft = sp->prevnleft; 363 parselleft = sp->prevlleft; 364 /*dprintf("*** calling popstring: restoring to '%s'\n", parsenextc);*/ 365 if (sp->ap) 366 sp->ap->flag &= ~ALIASINUSE; 367 parsefile->strpush = sp->prev; 368 if (sp != &(parsefile->basestrpush)) 369 ckfree(sp); 370 INTON; 371 } 372 373 /* 374 * Set the input to take input from a file. If push is set, push the 375 * old input onto the stack first. 376 */ 377 378 void 379 setinputfile(fname, push) 380 char *fname; 381 int push; 382 { 383 int fd; 384 int fd2; 385 386 INTOFF; 387 if ((fd = open(fname, O_RDONLY)) < 0) 388 error("Can't open %s", fname); 389 if (fd < 10) { 390 fd2 = copyfd(fd, 10); 391 close(fd); 392 if (fd2 < 0) 393 error("Out of file descriptors"); 394 fd = fd2; 395 } 396 setinputfd(fd, push); 397 INTON; 398 } 399 400 401 /* 402 * Like setinputfile, but takes an open file descriptor. Call this with 403 * interrupts off. 404 */ 405 406 void 407 setinputfd(fd, push) 408 int fd, push; 409 { 410 if (push) { 411 pushfile(); 412 parsefile->buf = ckmalloc(BUFSIZ); 413 } 414 if (parsefile->fd > 0) 415 close(parsefile->fd); 416 parsefile->fd = fd; 417 if (parsefile->buf == NULL) 418 parsefile->buf = ckmalloc(BUFSIZ); 419 parselleft = parsenleft = 0; 420 plinno = 1; 421 } 422 423 424 /* 425 * Like setinputfile, but takes input from a string. 426 */ 427 428 void 429 setinputstring(string, push) 430 char *string; 431 int push; 432 { 433 INTOFF; 434 if (push) 435 pushfile(); 436 parsenextc = string; 437 parselleft = parsenleft = strlen(string); 438 parsefile->buf = NULL; 439 plinno = 1; 440 INTON; 441 } 442 443 444 445 /* 446 * To handle the "." command, a stack of input files is used. Pushfile 447 * adds a new entry to the stack and popfile restores the previous level. 448 */ 449 450 STATIC void 451 pushfile() { 452 struct parsefile *pf; 453 454 parsefile->nleft = parsenleft; 455 parsefile->lleft = parselleft; 456 parsefile->nextc = parsenextc; 457 parsefile->linno = plinno; 458 pf = (struct parsefile *)ckmalloc(sizeof (struct parsefile)); 459 pf->prev = parsefile; 460 pf->fd = -1; 461 pf->strpush = NULL; 462 pf->basestrpush.prev = NULL; 463 parsefile = pf; 464 } 465 466 467 void 468 popfile() { 469 struct parsefile *pf = parsefile; 470 471 INTOFF; 472 if (pf->fd >= 0) 473 close(pf->fd); 474 if (pf->buf) 475 ckfree(pf->buf); 476 while (pf->strpush) 477 popstring(); 478 parsefile = pf->prev; 479 ckfree(pf); 480 parsenleft = parsefile->nleft; 481 parselleft = parsefile->lleft; 482 parsenextc = parsefile->nextc; 483 plinno = parsefile->linno; 484 INTON; 485 } 486 487 488 /* 489 * Return to top level. 490 */ 491 492 void 493 popallfiles() { 494 while (parsefile != &basepf) 495 popfile(); 496 } 497 498 499 500 /* 501 * Close the file(s) that the shell is reading commands from. Called 502 * after a fork is done. 503 */ 504 505 void 506 closescript() { 507 popallfiles(); 508 if (parsefile->fd > 0) { 509 close(parsefile->fd); 510 parsefile->fd = 0; 511 } 512 } 513