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 1.3 1995/05/30 00:07:15 rgrimes Exp $ 37 */ 38 39 #ifndef lint 40 static char sccsid[] = "@(#)input.c 8.1 (Berkeley) 5/31/93"; 41 #endif /* not lint */ 42 43 /* 44 * This file implements the input routines used by the parser. 45 */ 46 47 #include <stdio.h> /* defines BUFSIZ */ 48 #include "shell.h" 49 #include <fcntl.h> 50 #include <errno.h> 51 #include "syntax.h" 52 #include "input.h" 53 #include "output.h" 54 #include "options.h" 55 #include "memalloc.h" 56 #include "error.h" 57 #include "alias.h" 58 #include "parser.h" 59 #include "myhistedit.h" 60 61 #define EOF_NLEFT -99 /* value of parsenleft when EOF pushed back */ 62 63 MKINIT 64 struct strpush { 65 struct strpush *prev; /* preceding string on stack */ 66 char *prevstring; 67 int prevnleft; 68 int prevlleft; 69 struct alias *ap; /* if push was associated with an alias */ 70 }; 71 72 /* 73 * The parsefile structure pointed to by the global variable parsefile 74 * contains information about the current file being read. 75 */ 76 77 MKINIT 78 struct parsefile { 79 struct parsefile *prev; /* preceding file on stack */ 80 int linno; /* current line */ 81 int fd; /* file descriptor (or -1 if string) */ 82 int nleft; /* number of chars left in line */ 83 int lleft; /* number of lines left in buffer */ 84 char *nextc; /* next char in buffer */ 85 char *buf; /* input buffer */ 86 struct strpush *strpush; /* for pushing strings at this level */ 87 struct strpush basestrpush; /* so pushing one is fast */ 88 }; 89 90 91 int plinno = 1; /* input line number */ 92 MKINIT int parsenleft; /* copy of parsefile->nleft */ 93 MKINIT int parselleft; /* copy of parsefile->lleft */ 94 char *parsenextc; /* copy of parsefile->nextc */ 95 MKINIT struct parsefile basepf; /* top level input file */ 96 char basebuf[BUFSIZ]; /* buffer for top level input file */ 97 struct parsefile *parsefile = &basepf; /* current input file */ 98 int init_editline = 0; /* editline library initialized? */ 99 int whichprompt; /* 1 == PS1, 2 == PS2 */ 100 101 EditLine *el; /* cookie for editline package */ 102 103 #ifdef __STDC__ 104 STATIC void pushfile(void); 105 #else 106 STATIC void pushfile(); 107 #endif 108 109 110 111 #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 { 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 int len; 182 183 rl_cp = el_gets(el, &nr); 184 if (rl_cp == NULL) 185 nr = 0; 186 else { 187 /* XXX - BUFSIZE should redesign so not necessary */ 188 strcpy(parsenextc, rl_cp); 189 } 190 191 } else { 192 nr = read(parsefile->fd, parsenextc, BUFSIZ - 1); 193 } 194 195 if (nr <= 0) { 196 if (nr < 0) { 197 if (errno == EINTR) 198 goto retry; 199 if (parsefile->fd == 0 && errno == EWOULDBLOCK) { 200 int flags = fcntl(0, F_GETFL, 0); 201 if (flags >= 0 && flags & O_NONBLOCK) { 202 flags &=~ O_NONBLOCK; 203 if (fcntl(0, F_SETFL, flags) >= 0) { 204 out2str("sh: turning off NDELAY mode\n"); 205 goto retry; 206 } 207 } 208 } 209 } 210 nr = -1; 211 } 212 return nr; 213 } 214 215 /* 216 * Refill the input buffer and return the next input character: 217 * 218 * 1) If a string was pushed back on the input, pop it; 219 * 2) If an EOF was pushed back (parsenleft == EOF_NLEFT) or we are reading 220 * from a string so we can't refill the buffer, return EOF. 221 * 3) If there is more in the buffer, use it; else call read to fill it. 222 * 4) Process input up to next newline, deleting nul characters. 223 */ 224 225 int 226 preadbuffer() { 227 char *p, *q; 228 int more; 229 int something; 230 extern EditLine *el; 231 char savec; 232 233 if (parsefile->strpush) { 234 popstring(); 235 if (--parsenleft >= 0) 236 return (*parsenextc++); 237 } 238 if (parsenleft == EOF_NLEFT || parsefile->buf == NULL) 239 return PEOF; 240 flushout(&output); 241 flushout(&errout); 242 243 again: 244 if (parselleft <= 0) { 245 if ((parselleft = pread()) == -1) { 246 parselleft = parsenleft = EOF_NLEFT; 247 return PEOF; 248 } 249 } 250 251 q = p = parsenextc; 252 253 /* delete nul characters */ 254 something = 0; 255 for (more = 1; more;) { 256 switch (*p) { 257 case '\0': 258 p++; /* Skip nul */ 259 goto check; 260 261 case '\t': 262 case ' ': 263 break; 264 265 case '\n': 266 parsenleft = q - parsenextc; 267 more = 0; /* Stop processing here */ 268 break; 269 270 default: 271 something = 1; 272 break; 273 } 274 275 *q++ = *p++; 276 check: 277 if (--parselleft <= 0) { 278 parsenleft = q - parsenextc - 1; 279 if (parsenleft < 0) 280 goto again; 281 *q = '\0'; 282 more = 0; 283 } 284 } 285 286 savec = *q; 287 *q = '\0'; 288 289 290 if (parsefile->fd == 0 && hist && something) { 291 INTOFF; 292 history(hist, whichprompt == 1 ? H_ENTER : H_ADD, parsenextc); 293 INTON; 294 } 295 296 297 if (vflag) { 298 out2str(parsenextc); 299 flushout(out2); 300 } 301 302 *q = savec; 303 304 return *parsenextc++; 305 } 306 307 /* 308 * Undo the last call to pgetc. Only one character may be pushed back. 309 * PEOF may be pushed back. 310 */ 311 312 void 313 pungetc() { 314 parsenleft++; 315 parsenextc--; 316 } 317 318 /* 319 * Push a string back onto the input at this current parsefile level. 320 * We handle aliases this way. 321 */ 322 void 323 pushstring(s, len, ap) 324 char *s; 325 int len; 326 void *ap; 327 { 328 struct strpush *sp; 329 330 INTOFF; 331 /*dprintf("*** calling pushstring: %s, %d\n", s, len);*/ 332 if (parsefile->strpush) { 333 sp = ckmalloc(sizeof (struct strpush)); 334 sp->prev = parsefile->strpush; 335 parsefile->strpush = sp; 336 } else 337 sp = parsefile->strpush = &(parsefile->basestrpush); 338 sp->prevstring = parsenextc; 339 sp->prevnleft = parsenleft; 340 sp->prevlleft = parselleft; 341 sp->ap = (struct alias *)ap; 342 if (ap) 343 ((struct alias *)ap)->flag |= ALIASINUSE; 344 parsenextc = s; 345 parsenleft = len; 346 INTON; 347 } 348 349 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 { 375 int fd; 376 int fd2; 377 378 INTOFF; 379 if ((fd = open(fname, O_RDONLY)) < 0) 380 error("Can't open %s", fname); 381 if (fd < 10) { 382 fd2 = copyfd(fd, 10); 383 close(fd); 384 if (fd2 < 0) 385 error("Out of file descriptors"); 386 fd = fd2; 387 } 388 setinputfd(fd, push); 389 INTON; 390 } 391 392 393 /* 394 * Like setinputfile, but takes an open file descriptor. Call this with 395 * interrupts off. 396 */ 397 398 void 399 setinputfd(fd, push) { 400 if (push) { 401 pushfile(); 402 parsefile->buf = ckmalloc(BUFSIZ); 403 } 404 if (parsefile->fd > 0) 405 close(parsefile->fd); 406 parsefile->fd = fd; 407 if (parsefile->buf == NULL) 408 parsefile->buf = ckmalloc(BUFSIZ); 409 parselleft = parsenleft = 0; 410 plinno = 1; 411 } 412 413 414 /* 415 * Like setinputfile, but takes input from a string. 416 */ 417 418 void 419 setinputstring(string, push) 420 char *string; 421 { 422 INTOFF; 423 if (push) 424 pushfile(); 425 parsenextc = string; 426 parselleft = parsenleft = strlen(string); 427 parsefile->buf = NULL; 428 plinno = 1; 429 INTON; 430 } 431 432 433 434 /* 435 * To handle the "." command, a stack of input files is used. Pushfile 436 * adds a new entry to the stack and popfile restores the previous level. 437 */ 438 439 STATIC void 440 pushfile() { 441 struct parsefile *pf; 442 443 parsefile->nleft = parsenleft; 444 parsefile->lleft = parselleft; 445 parsefile->nextc = parsenextc; 446 parsefile->linno = plinno; 447 pf = (struct parsefile *)ckmalloc(sizeof (struct parsefile)); 448 pf->prev = parsefile; 449 pf->fd = -1; 450 pf->strpush = NULL; 451 pf->basestrpush.prev = NULL; 452 parsefile = pf; 453 } 454 455 456 void 457 popfile() { 458 struct parsefile *pf = parsefile; 459 460 INTOFF; 461 if (pf->fd >= 0) 462 close(pf->fd); 463 if (pf->buf) 464 ckfree(pf->buf); 465 while (pf->strpush) 466 popstring(); 467 parsefile = pf->prev; 468 ckfree(pf); 469 parsenleft = parsefile->nleft; 470 parselleft = parsefile->lleft; 471 parsenextc = parsefile->nextc; 472 plinno = parsefile->linno; 473 INTON; 474 } 475 476 477 /* 478 * Return to top level. 479 */ 480 481 void 482 popallfiles() { 483 while (parsefile != &basepf) 484 popfile(); 485 } 486 487 488 489 /* 490 * Close the file(s) that the shell is reading commands from. Called 491 * after a fork is done. 492 */ 493 494 void 495 closescript() { 496 popallfiles(); 497 if (parsefile->fd > 0) { 498 close(parsefile->fd); 499 parsefile->fd = 0; 500 } 501 } 502