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 1.5 1996/09/01 10:20:18 peter Exp $ 37 */ 38 39 #ifndef lint 40 static char 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 line */ 88 int lleft; /* number of lines left in 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)); 109 110 #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(line, len) 138 char *line; 139 int len; 140 { 141 register char *p = line; 142 int nleft = len; 143 int c; 144 145 while (--nleft > 0) { 146 c = pgetc_macro(); 147 if (c == PEOF) { 148 if (p == line) 149 return NULL; 150 break; 151 } 152 *p++ = c; 153 if (c == '\n') 154 break; 155 } 156 *p = '\0'; 157 return line; 158 } 159 160 161 162 /* 163 * Read a character from the script, returning PEOF on end of file. 164 * Nul characters in the input are silently discarded. 165 */ 166 167 int 168 pgetc() { 169 return pgetc_macro(); 170 } 171 172 static int 173 pread() 174 { 175 int nr; 176 177 parsenextc = parsefile->buf; 178 retry: 179 if (parsefile->fd == 0 && el) { 180 const char *rl_cp; 181 182 rl_cp = el_gets(el, &nr); 183 if (rl_cp == NULL) 184 nr = 0; 185 else { 186 /* XXX - BUFSIZE should redesign so not necessary */ 187 (void)strcpy(parsenextc, rl_cp); 188 } 189 190 } else { 191 nr = read(parsefile->fd, parsenextc, BUFSIZ - 1); 192 } 193 194 if (nr <= 0) { 195 if (nr < 0) { 196 if (errno == EINTR) 197 goto retry; 198 if (parsefile->fd == 0 && errno == EWOULDBLOCK) { 199 int flags = fcntl(0, F_GETFL, 0); 200 if (flags >= 0 && flags & O_NONBLOCK) { 201 flags &=~ O_NONBLOCK; 202 if (fcntl(0, F_SETFL, flags) >= 0) { 203 out2str("sh: turning off NDELAY mode\n"); 204 goto retry; 205 } 206 } 207 } 208 } 209 nr = -1; 210 } 211 return nr; 212 } 213 214 /* 215 * Refill the input buffer and return the next input character: 216 * 217 * 1) If a string was pushed back on the input, pop it; 218 * 2) If an EOF was pushed back (parsenleft == EOF_NLEFT) or we are reading 219 * from a string so we can't refill the buffer, return EOF. 220 * 3) If there is more in the buffer, use it; else call read to fill it. 221 * 4) Process input up to next newline, deleting nul characters. 222 */ 223 224 int 225 preadbuffer() { 226 char *p, *q; 227 int more; 228 int something; 229 extern EditLine *el; 230 char savec; 231 232 if (parsefile->strpush) { 233 popstring(); 234 if (--parsenleft >= 0) 235 return (*parsenextc++); 236 } 237 if (parsenleft == EOF_NLEFT || parsefile->buf == NULL) 238 return PEOF; 239 flushout(&output); 240 flushout(&errout); 241 242 again: 243 if (parselleft <= 0) { 244 if ((parselleft = pread()) == -1) { 245 parselleft = parsenleft = EOF_NLEFT; 246 return PEOF; 247 } 248 } 249 250 q = p = parsenextc; 251 252 /* delete nul characters */ 253 something = 0; 254 for (more = 1; more;) { 255 switch (*p) { 256 case '\0': 257 p++; /* Skip nul */ 258 goto check; 259 260 case '\t': 261 case ' ': 262 break; 263 264 case '\n': 265 parsenleft = q - parsenextc; 266 more = 0; /* Stop processing here */ 267 break; 268 269 default: 270 something = 1; 271 break; 272 } 273 274 *q++ = *p++; 275 check: 276 if (--parselleft <= 0) { 277 parsenleft = q - parsenextc - 1; 278 if (parsenleft < 0) 279 goto again; 280 *q = '\0'; 281 more = 0; 282 } 283 } 284 285 savec = *q; 286 *q = '\0'; 287 288 #ifndef NO_HISTORY 289 if (parsefile->fd == 0 && hist && something) { 290 INTOFF; 291 history(hist, whichprompt == 1 ? H_ENTER : H_ADD, parsenextc); 292 INTON; 293 } 294 #endif 295 296 if (vflag) { 297 out2str(parsenextc); 298 flushout(out2); 299 } 300 301 *q = savec; 302 303 return *parsenextc++; 304 } 305 306 /* 307 * Undo the last call to pgetc. Only one character may be pushed back. 308 * PEOF may be pushed back. 309 */ 310 311 void 312 pungetc() { 313 parsenleft++; 314 parsenextc--; 315 } 316 317 /* 318 * Push a string back onto the input at this current parsefile level. 319 * We handle aliases this way. 320 */ 321 void 322 pushstring(s, len, ap) 323 char *s; 324 int len; 325 void *ap; 326 { 327 struct strpush *sp; 328 329 INTOFF; 330 /*dprintf("*** calling pushstring: %s, %d\n", s, len);*/ 331 if (parsefile->strpush) { 332 sp = ckmalloc(sizeof (struct strpush)); 333 sp->prev = parsefile->strpush; 334 parsefile->strpush = sp; 335 } else 336 sp = parsefile->strpush = &(parsefile->basestrpush); 337 sp->prevstring = parsenextc; 338 sp->prevnleft = parsenleft; 339 sp->prevlleft = parselleft; 340 sp->ap = (struct alias *)ap; 341 if (ap) 342 ((struct alias *)ap)->flag |= ALIASINUSE; 343 parsenextc = s; 344 parsenleft = len; 345 INTON; 346 } 347 348 void 349 popstring() 350 { 351 struct strpush *sp = parsefile->strpush; 352 353 INTOFF; 354 parsenextc = sp->prevstring; 355 parsenleft = sp->prevnleft; 356 parselleft = sp->prevlleft; 357 /*dprintf("*** calling popstring: restoring to '%s'\n", parsenextc);*/ 358 if (sp->ap) 359 sp->ap->flag &= ~ALIASINUSE; 360 parsefile->strpush = sp->prev; 361 if (sp != &(parsefile->basestrpush)) 362 ckfree(sp); 363 INTON; 364 } 365 366 /* 367 * Set the input to take input from a file. If push is set, push the 368 * old input onto the stack first. 369 */ 370 371 void 372 setinputfile(fname, push) 373 char *fname; 374 int push; 375 { 376 int fd; 377 int fd2; 378 379 INTOFF; 380 if ((fd = open(fname, O_RDONLY)) < 0) 381 error("Can't open %s", fname); 382 if (fd < 10) { 383 fd2 = copyfd(fd, 10); 384 close(fd); 385 if (fd2 < 0) 386 error("Out of file descriptors"); 387 fd = fd2; 388 } 389 setinputfd(fd, push); 390 INTON; 391 } 392 393 394 /* 395 * Like setinputfile, but takes an open file descriptor. Call this with 396 * interrupts off. 397 */ 398 399 void 400 setinputfd(fd, push) 401 int fd, push; 402 { 403 if (push) { 404 pushfile(); 405 parsefile->buf = ckmalloc(BUFSIZ); 406 } 407 if (parsefile->fd > 0) 408 close(parsefile->fd); 409 parsefile->fd = fd; 410 if (parsefile->buf == NULL) 411 parsefile->buf = ckmalloc(BUFSIZ); 412 parselleft = parsenleft = 0; 413 plinno = 1; 414 } 415 416 417 /* 418 * Like setinputfile, but takes input from a string. 419 */ 420 421 void 422 setinputstring(string, push) 423 char *string; 424 int push; 425 { 426 INTOFF; 427 if (push) 428 pushfile(); 429 parsenextc = string; 430 parselleft = parsenleft = strlen(string); 431 parsefile->buf = NULL; 432 plinno = 1; 433 INTON; 434 } 435 436 437 438 /* 439 * To handle the "." command, a stack of input files is used. Pushfile 440 * adds a new entry to the stack and popfile restores the previous level. 441 */ 442 443 STATIC void 444 pushfile() { 445 struct parsefile *pf; 446 447 parsefile->nleft = parsenleft; 448 parsefile->lleft = parselleft; 449 parsefile->nextc = parsenextc; 450 parsefile->linno = plinno; 451 pf = (struct parsefile *)ckmalloc(sizeof (struct parsefile)); 452 pf->prev = parsefile; 453 pf->fd = -1; 454 pf->strpush = NULL; 455 pf->basestrpush.prev = NULL; 456 parsefile = pf; 457 } 458 459 460 void 461 popfile() { 462 struct parsefile *pf = parsefile; 463 464 INTOFF; 465 if (pf->fd >= 0) 466 close(pf->fd); 467 if (pf->buf) 468 ckfree(pf->buf); 469 while (pf->strpush) 470 popstring(); 471 parsefile = pf->prev; 472 ckfree(pf); 473 parsenleft = parsefile->nleft; 474 parselleft = parsefile->lleft; 475 parsenextc = parsefile->nextc; 476 plinno = parsefile->linno; 477 INTON; 478 } 479 480 481 /* 482 * Return to top level. 483 */ 484 485 void 486 popallfiles() { 487 while (parsefile != &basepf) 488 popfile(); 489 } 490 491 492 493 /* 494 * Close the file(s) that the shell is reading commands from. Called 495 * after a fork is done. 496 */ 497 498 void 499 closescript() { 500 popallfiles(); 501 if (parsefile->fd > 0) { 502 close(parsefile->fd); 503 parsefile->fd = 0; 504 } 505 } 506