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 37 #ifndef lint 38 /*static char sccsid[] = "from: @(#)input.c 8.1 (Berkeley) 5/31/93";*/ 39 static char *rcsid = "$Id: input.c,v 1.11 1994/12/04 07:12:14 cgd Exp $"; 40 #endif /* not lint */ 41 42 /* 43 * This file implements the input routines used by the parser. 44 */ 45 46 #include <stdio.h> /* defines BUFSIZ */ 47 #include <fcntl.h> 48 #include <errno.h> 49 #include <unistd.h> 50 #include "shell.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 "extern.h" 60 #ifndef NO_HISTORY 61 #include "myhistedit.h" 62 #endif 63 64 #define EOF_NLEFT -99 /* value of parsenleft when EOF pushed back */ 65 66 MKINIT 67 struct strpush { 68 struct strpush *prev; /* preceding string on stack */ 69 char *prevstring; 70 int prevnleft; 71 struct alias *ap; /* if push was associated with an alias */ 72 }; 73 74 /* 75 * The parsefile structure pointed to by the global variable parsefile 76 * contains information about the current file being read. 77 */ 78 79 MKINIT 80 struct parsefile { 81 struct parsefile *prev; /* preceding file on stack */ 82 int linno; /* current line */ 83 int fd; /* file descriptor (or -1 if string) */ 84 int nleft; /* number of chars left in buffer */ 85 char *nextc; /* next char in buffer */ 86 char *buf; /* input buffer */ 87 struct strpush *strpush; /* for pushing strings at this level */ 88 struct strpush basestrpush; /* so pushing one is fast */ 89 }; 90 91 92 int plinno = 1; /* input line number */ 93 MKINIT int parsenleft; /* copy of parsefile->nleft */ 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 char *pushedstring; /* copy of parsenextc when text pushed back */ 99 int pushednleft; /* copy of parsenleft when text pushed back */ 100 int init_editline = 0; /* editline library initialized? */ 101 int whichprompt; /* 1 == PS1, 2 == PS2 */ 102 103 #ifndef NO_HISTORY 104 EditLine *el; /* cookie for editline package */ 105 #endif 106 107 #ifdef __STDC__ 108 STATIC void pushfile(void); 109 #else 110 STATIC void pushfile(); 111 #endif 112 113 void popstring(); 114 115 116 117 #ifdef mkinit 118 INCLUDE "input.h" 119 INCLUDE "error.h" 120 121 INIT { 122 extern char basebuf[]; 123 124 basepf.nextc = basepf.buf = basebuf; 125 } 126 127 RESET { 128 if (exception != EXSHELLPROC) 129 parsenleft = 0; /* clear input buffer */ 130 popallfiles(); 131 } 132 133 SHELLPROC { 134 popallfiles(); 135 } 136 #endif 137 138 139 /* 140 * Read a line from the script. 141 */ 142 143 char * 144 pfgets(line, len) 145 char *line; 146 int len; 147 { 148 register char *p = line; 149 int nleft = len; 150 int c; 151 152 while (--nleft > 0) { 153 c = pgetc_macro(); 154 if (c == PEOF) { 155 if (p == line) 156 return NULL; 157 break; 158 } 159 *p++ = c; 160 if (c == '\n') 161 break; 162 } 163 *p = '\0'; 164 return line; 165 } 166 167 168 169 /* 170 * Read a character from the script, returning PEOF on end of file. 171 * Nul characters in the input are silently discarded. 172 */ 173 174 int 175 pgetc() { 176 return pgetc_macro(); 177 } 178 179 180 /* 181 * Refill the input buffer and return the next input character: 182 * 183 * 1) If a string was pushed back on the input, pop it; 184 * 2) If an EOF was pushed back (parsenleft == EOF_NLEFT) or we are reading 185 * from a string so we can't refill the buffer, return EOF. 186 * 3) Call read to read in the characters. 187 * 4) Delete all nul characters from the buffer. 188 */ 189 190 int 191 preadbuffer() { 192 register char *p, *q; 193 register int i; 194 register int something; 195 #ifndef NO_HISTORY 196 extern EditLine *el; 197 #endif 198 199 if (parsefile->strpush) { 200 popstring(); 201 if (--parsenleft >= 0) 202 return (*parsenextc++); 203 } 204 if (parsenleft == EOF_NLEFT || parsefile->buf == NULL) 205 return PEOF; 206 flushout(&output); 207 flushout(&errout); 208 retry: 209 p = parsenextc = parsefile->buf; 210 #ifndef NO_HISTORY 211 if (parsefile->fd == 0 && el) { 212 const char *rl_cp; 213 int len; 214 215 rl_cp = el_gets(el, &len); 216 if (rl_cp == NULL) { 217 i = 0; 218 goto eof; 219 } 220 strcpy(p, rl_cp); /* XXX - BUFSIZE should redesign so not necessary */ 221 i = len; 222 223 } else { 224 #endif 225 regular_read: 226 i = read(parsefile->fd, p, BUFSIZ - 1); 227 #ifndef NO_HISTORY 228 } 229 #endif 230 eof: 231 if (i <= 0) { 232 if (i < 0) { 233 if (errno == EINTR) 234 goto retry; 235 if (parsefile->fd == 0 && errno == EWOULDBLOCK) { 236 int flags = fcntl(0, F_GETFL, 0); 237 if (flags >= 0 && flags & O_NONBLOCK) { 238 flags &=~ O_NONBLOCK; 239 if (fcntl(0, F_SETFL, flags) >= 0) { 240 out2str("sh: turning off NDELAY mode\n"); 241 goto retry; 242 } 243 } 244 } 245 } 246 parsenleft = EOF_NLEFT; 247 return PEOF; 248 } 249 parsenleft = i - 1; /* we're returning one char in this call */ 250 251 /* delete nul characters */ 252 something = 0; 253 for (;;) { 254 if (*p == '\0') 255 break; 256 if (*p != ' ' && *p != '\t' && *p != '\n') 257 something = 1; 258 p++; 259 if (--i <= 0) { 260 *p = '\0'; 261 goto done; /* no nul characters */ 262 } 263 } 264 /* 265 * remove nuls 266 */ 267 q = p++; 268 while (--i > 0) { 269 if (*p != '\0') 270 *q++ = *p; 271 p++; 272 } 273 *q = '\0'; 274 if (q == parsefile->buf) 275 goto retry; /* buffer contained nothing but nuls */ 276 parsenleft = q - parsefile->buf - 1; 277 278 done: 279 #ifndef NO_HISTORY 280 if (parsefile->fd == 0 && hist && something) { 281 INTOFF; 282 history(hist, whichprompt == 1 ? H_ENTER : H_ADD, 283 parsefile->buf); 284 INTON; 285 } 286 #endif 287 if (vflag) { 288 /* 289 * This isn't right. Most shells coordinate it with 290 * reading a line at a time. I honestly don't know if its 291 * worth it. 292 */ 293 i = parsenleft + 1; 294 p = parsefile->buf; 295 for (; i--; p++) 296 out2c(*p) 297 flushout(out2); 298 } 299 return *parsenextc++; 300 } 301 302 /* 303 * Undo the last call to pgetc. Only one character may be pushed back. 304 * PEOF may be pushed back. 305 */ 306 307 void 308 pungetc() { 309 parsenleft++; 310 parsenextc--; 311 } 312 313 /* 314 * Push a string back onto the input at this current parsefile level. 315 * We handle aliases this way. 316 */ 317 void 318 pushstring(s, len, ap) 319 char *s; 320 int len; 321 void *ap; 322 { 323 struct strpush *sp; 324 325 INTOFF; 326 /*dprintf("*** calling pushstring: %s, %d\n", s, len);*/ 327 if (parsefile->strpush) { 328 sp = ckmalloc(sizeof (struct strpush)); 329 sp->prev = parsefile->strpush; 330 parsefile->strpush = sp; 331 } else 332 sp = parsefile->strpush = &(parsefile->basestrpush); 333 sp->prevstring = parsenextc; 334 sp->prevnleft = parsenleft; 335 sp->ap = (struct alias *)ap; 336 if (ap) 337 ((struct alias *)ap)->flag |= ALIASINUSE; 338 parsenextc = s; 339 parsenleft = len; 340 INTON; 341 } 342 343 void 344 popstring() 345 { 346 struct strpush *sp = parsefile->strpush; 347 348 INTOFF; 349 parsenextc = sp->prevstring; 350 parsenleft = sp->prevnleft; 351 /*dprintf("*** calling popstring: restoring to '%s'\n", parsenextc);*/ 352 if (sp->ap) 353 sp->ap->flag &= ~ALIASINUSE; 354 parsefile->strpush = sp->prev; 355 if (sp != &(parsefile->basestrpush)) 356 ckfree(sp); 357 INTON; 358 } 359 360 /* 361 * Set the input to take input from a file. If push is set, push the 362 * old input onto the stack first. 363 */ 364 365 void 366 setinputfile(fname, push) 367 char *fname; 368 int push; 369 { 370 int fd; 371 int fd2; 372 373 INTOFF; 374 if ((fd = open(fname, O_RDONLY)) < 0) 375 error("Can't open %s", fname); 376 if (fd < 10) { 377 fd2 = copyfd(fd, 10); 378 close(fd); 379 if (fd2 < 0) 380 error("Out of file descriptors"); 381 fd = fd2; 382 } 383 setinputfd(fd, push); 384 INTON; 385 } 386 387 388 /* 389 * Like setinputfile, but takes an open file descriptor. Call this with 390 * interrupts off. 391 */ 392 393 void 394 setinputfd(fd, push) 395 int fd; 396 int push; 397 { 398 if (push) { 399 pushfile(); 400 parsefile->buf = ckmalloc(BUFSIZ); 401 } 402 if (parsefile->fd > 0) 403 close(parsefile->fd); 404 parsefile->fd = fd; 405 if (parsefile->buf == NULL) 406 parsefile->buf = ckmalloc(BUFSIZ); 407 parsenleft = 0; 408 plinno = 1; 409 } 410 411 412 /* 413 * Like setinputfile, but takes input from a string. 414 */ 415 416 void 417 setinputstring(string, push) 418 char *string; 419 int push; 420 { 421 INTOFF; 422 if (push) 423 pushfile(); 424 parsenextc = string; 425 parsenleft = strlen(string); 426 parsefile->buf = NULL; 427 plinno = 1; 428 INTON; 429 } 430 431 432 433 /* 434 * To handle the "." command, a stack of input files is used. Pushfile 435 * adds a new entry to the stack and popfile restores the previous level. 436 */ 437 438 STATIC void 439 pushfile() { 440 struct parsefile *pf; 441 442 parsefile->nleft = parsenleft; 443 parsefile->nextc = parsenextc; 444 parsefile->linno = plinno; 445 pf = (struct parsefile *)ckmalloc(sizeof (struct parsefile)); 446 pf->prev = parsefile; 447 pf->fd = -1; 448 pf->strpush = NULL; 449 pf->basestrpush.prev = NULL; 450 parsefile = pf; 451 } 452 453 454 void 455 popfile() { 456 struct parsefile *pf = parsefile; 457 458 INTOFF; 459 if (pf->fd >= 0) 460 close(pf->fd); 461 if (pf->buf) 462 ckfree(pf->buf); 463 while (pf->strpush) 464 popstring(); 465 parsefile = pf->prev; 466 ckfree(pf); 467 parsenleft = parsefile->nleft; 468 parsenextc = parsefile->nextc; 469 plinno = parsefile->linno; 470 INTON; 471 } 472 473 474 /* 475 * Return to top level. 476 */ 477 478 void 479 popallfiles() { 480 while (parsefile != &basepf) 481 popfile(); 482 } 483 484 485 486 /* 487 * Close the file(s) that the shell is reading commands from. Called 488 * after a fork is done. 489 */ 490 491 void 492 closescript() { 493 popallfiles(); 494 if (parsefile->fd > 0) { 495 close(parsefile->fd); 496 parsefile->fd = 0; 497 } 498 } 499