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 * $Id: input.c,v 1.6 1996/09/03 14:15:50 peter Exp $ 37 */ 38 39 #ifndef lint 40 static char const sccsid[] = "@(#)input.c 8.3 (Berkeley) 6/9/95"; 41 #endif /* not lint */ 42 43 #include <stdio.h> /* defines BUFSIZ */ 44 #include <fcntl.h> 45 #include <errno.h> 46 #include <unistd.h> 47 #include <stdlib.h> 48 #include <string.h> 49 50 /* 51 * This file implements the input routines used by the parser. 52 */ 53 54 #include "shell.h" 55 #include "redir.h" 56 #include "syntax.h" 57 #include "input.h" 58 #include "output.h" 59 #include "options.h" 60 #include "memalloc.h" 61 #include "error.h" 62 #include "alias.h" 63 #include "parser.h" 64 #include "myhistedit.h" 65 66 #define EOF_NLEFT -99 /* value of parsenleft when EOF pushed back */ 67 68 MKINIT 69 struct strpush { 70 struct strpush *prev; /* preceding string on stack */ 71 char *prevstring; 72 int prevnleft; 73 int prevlleft; 74 struct alias *ap; /* if push was associated with an alias */ 75 }; 76 77 /* 78 * The parsefile structure pointed to by the global variable parsefile 79 * contains information about the current file being read. 80 */ 81 82 MKINIT 83 struct parsefile { 84 struct parsefile *prev; /* preceding file on stack */ 85 int linno; /* current line */ 86 int fd; /* file descriptor (or -1 if string) */ 87 int nleft; /* number of chars left in this line */ 88 int lleft; /* number of lines left in this buffer */ 89 char *nextc; /* next char in buffer */ 90 char *buf; /* input buffer */ 91 struct strpush *strpush; /* for pushing strings at this level */ 92 struct strpush basestrpush; /* so pushing one is fast */ 93 }; 94 95 96 int plinno = 1; /* input line number */ 97 MKINIT int parsenleft; /* copy of parsefile->nleft */ 98 MKINIT int parselleft; /* copy of parsefile->lleft */ 99 char *parsenextc; /* copy of parsefile->nextc */ 100 MKINIT struct parsefile basepf; /* top level input file */ 101 char basebuf[BUFSIZ]; /* buffer for top level input file */ 102 struct parsefile *parsefile = &basepf; /* current input file */ 103 int init_editline = 0; /* editline library initialized? */ 104 int whichprompt; /* 1 == PS1, 2 == PS2 */ 105 106 EditLine *el; /* cookie for editline package */ 107 108 STATIC void pushfile __P((void)); 109 static int pread __P((void)); 110 111 #ifdef mkinit 112 INCLUDE "input.h" 113 INCLUDE "error.h" 114 115 INIT { 116 extern char basebuf[]; 117 118 basepf.nextc = basepf.buf = basebuf; 119 } 120 121 RESET { 122 if (exception != EXSHELLPROC) 123 parselleft = parsenleft = 0; /* clear input buffer */ 124 popallfiles(); 125 } 126 127 SHELLPROC { 128 popallfiles(); 129 } 130 #endif 131 132 133 /* 134 * Read a line from the script. 135 */ 136 137 char * 138 pfgets(line, len) 139 char *line; 140 int len; 141 { 142 register char *p = line; 143 int nleft = len; 144 int c; 145 146 while (--nleft > 0) { 147 c = pgetc_macro(); 148 if (c == PEOF) { 149 if (p == line) 150 return NULL; 151 break; 152 } 153 *p++ = c; 154 if (c == '\n') 155 break; 156 } 157 *p = '\0'; 158 return line; 159 } 160 161 162 163 /* 164 * Read a character from the script, returning PEOF on end of file. 165 * Nul characters in the input are silently discarded. 166 */ 167 168 int 169 pgetc() 170 { 171 return pgetc_macro(); 172 } 173 174 175 static int 176 pread() 177 { 178 int nr; 179 parsenextc = parsefile->buf; 180 181 retry: 182 if (parsefile->fd == 0 && el) { 183 const char *rl_cp; 184 185 rl_cp = el_gets(el, &nr); 186 if (rl_cp == NULL) 187 nr = 0; 188 else { 189 /* XXX - BUFSIZE should redesign so not necessary */ 190 (void) strcpy(parsenextc, rl_cp); 191 } 192 } else { 193 nr = read(parsefile->fd, parsenextc, BUFSIZ - 1); 194 } 195 196 if (nr <= 0) { 197 if (nr < 0) { 198 if (errno == EINTR) 199 goto retry; 200 if (parsefile->fd == 0 && errno == EWOULDBLOCK) { 201 int flags = fcntl(0, F_GETFL, 0); 202 if (flags >= 0 && flags & O_NONBLOCK) { 203 flags &=~ O_NONBLOCK; 204 if (fcntl(0, F_SETFL, flags) >= 0) { 205 out2str("sh: turning off NDELAY mode\n"); 206 goto retry; 207 } 208 } 209 } 210 } 211 nr = -1; 212 } 213 return nr; 214 } 215 216 /* 217 * Refill the input buffer and return the next input character: 218 * 219 * 1) If a string was pushed back on the input, pop it; 220 * 2) If an EOF was pushed back (parsenleft == EOF_NLEFT) or we are reading 221 * from a string so we can't refill the buffer, return EOF. 222 * 3) If there is more in this buffer, use it else call read to fill it. 223 * 4) Process input up to the next newline, deleting nul characters. 224 */ 225 226 int 227 preadbuffer() 228 { 229 char *p, *q; 230 int more; 231 int something; 232 extern EditLine *el; 233 char savec; 234 235 if (parsefile->strpush) { 236 popstring(); 237 if (--parsenleft >= 0) 238 return (*parsenextc++); 239 } 240 if (parsenleft == EOF_NLEFT || parsefile->buf == NULL) 241 return PEOF; 242 flushout(&output); 243 flushout(&errout); 244 245 again: 246 if (parselleft <= 0) { 247 if ((parselleft = pread()) == -1) { 248 parselleft = parsenleft = EOF_NLEFT; 249 return PEOF; 250 } 251 } 252 253 q = p = parsenextc; 254 255 /* delete nul characters */ 256 something = 0; 257 for (more = 1; more;) { 258 switch (*p) { 259 case '\0': 260 p++; /* Skip nul */ 261 goto check; 262 263 case '\t': 264 case ' ': 265 break; 266 267 case '\n': 268 parsenleft = q - parsenextc; 269 more = 0; /* Stop processing here */ 270 break; 271 272 default: 273 something = 1; 274 break; 275 } 276 277 *q++ = *p++; 278 check: 279 if (--parselleft <= 0) { 280 parsenleft = q - parsenextc - 1; 281 if (parsenleft < 0) 282 goto again; 283 *q = '\0'; 284 more = 0; 285 } 286 } 287 288 savec = *q; 289 *q = '\0'; 290 291 #ifndef NO_HISTORY 292 if (parsefile->fd == 0 && hist && something) { 293 INTOFF; 294 history(hist, whichprompt == 1 ? H_ENTER : H_ADD, parsenextc); 295 INTON; 296 } 297 #endif 298 299 if (vflag) { 300 out2str(parsenextc); 301 flushout(out2); 302 } 303 304 *q = savec; 305 306 return *parsenextc++; 307 } 308 309 /* 310 * Undo the last call to pgetc. Only one character may be pushed back. 311 * PEOF may be pushed back. 312 */ 313 314 void 315 pungetc() { 316 parsenleft++; 317 parsenextc--; 318 } 319 320 /* 321 * Push a string back onto the input at this current parsefile level. 322 * We handle aliases this way. 323 */ 324 void 325 pushstring(s, len, ap) 326 char *s; 327 int len; 328 void *ap; 329 { 330 struct strpush *sp; 331 332 INTOFF; 333 /*dprintf("*** calling pushstring: %s, %d\n", s, len);*/ 334 if (parsefile->strpush) { 335 sp = ckmalloc(sizeof (struct strpush)); 336 sp->prev = parsefile->strpush; 337 parsefile->strpush = sp; 338 } else 339 sp = parsefile->strpush = &(parsefile->basestrpush); 340 sp->prevstring = parsenextc; 341 sp->prevnleft = parsenleft; 342 sp->prevlleft = parselleft; 343 sp->ap = (struct alias *)ap; 344 if (ap) 345 ((struct alias *)ap)->flag |= ALIASINUSE; 346 parsenextc = s; 347 parsenleft = len; 348 INTON; 349 } 350 351 void 352 popstring() 353 { 354 struct strpush *sp = parsefile->strpush; 355 356 INTOFF; 357 parsenextc = sp->prevstring; 358 parsenleft = sp->prevnleft; 359 parselleft = sp->prevlleft; 360 /*dprintf("*** calling popstring: restoring to '%s'\n", parsenextc);*/ 361 if (sp->ap) 362 sp->ap->flag &= ~ALIASINUSE; 363 parsefile->strpush = sp->prev; 364 if (sp != &(parsefile->basestrpush)) 365 ckfree(sp); 366 INTON; 367 } 368 369 /* 370 * Set the input to take input from a file. If push is set, push the 371 * old input onto the stack first. 372 */ 373 374 void 375 setinputfile(fname, push) 376 char *fname; 377 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", fname); 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(fd, push) 404 int fd, push; 405 { 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(string, push) 426 char *string; 427 int push; 428 { 429 INTOFF; 430 if (push) 431 pushfile(); 432 parsenextc = string; 433 parselleft = parsenleft = strlen(string); 434 parsefile->buf = NULL; 435 plinno = 1; 436 INTON; 437 } 438 439 440 441 /* 442 * To handle the "." command, a stack of input files is used. Pushfile 443 * adds a new entry to the stack and popfile restores the previous level. 444 */ 445 446 STATIC void 447 pushfile() { 448 struct parsefile *pf; 449 450 parsefile->nleft = parsenleft; 451 parsefile->lleft = parselleft; 452 parsefile->nextc = parsenextc; 453 parsefile->linno = plinno; 454 pf = (struct parsefile *)ckmalloc(sizeof (struct parsefile)); 455 pf->prev = parsefile; 456 pf->fd = -1; 457 pf->strpush = NULL; 458 pf->basestrpush.prev = NULL; 459 parsefile = pf; 460 } 461 462 463 void 464 popfile() { 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() { 490 while (parsefile != &basepf) 491 popfile(); 492 } 493 494 495 496 /* 497 * Close the file(s) that the shell is reading commands from. Called 498 * after a fork is done. 499 */ 500 501 void 502 closescript() { 503 popallfiles(); 504 if (parsefile->fd > 0) { 505 close(parsefile->fd); 506 parsefile->fd = 0; 507 } 508 } 509