1 /* $NetBSD: chk.c,v 1.23 2017/12/26 17:02:19 christos Exp $ */ 2 3 /* 4 * Copyright (c) 1996 Christopher G. Demetriou. All Rights Reserved. 5 * Copyright (c) 1994, 1995 Jochen Pohl 6 * All Rights Reserved. 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 Jochen Pohl for 19 * The NetBSD Project. 20 * 4. The name of the author may not be used to endorse or promote products 21 * derived from this software without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 24 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 25 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 26 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 27 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 28 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 29 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 30 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 31 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 32 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 33 */ 34 35 #if HAVE_NBTOOL_CONFIG_H 36 #include "nbtool_config.h" 37 #endif 38 39 #include <sys/cdefs.h> 40 #if defined(__RCSID) && !defined(lint) 41 __RCSID("$NetBSD: chk.c,v 1.23 2017/12/26 17:02:19 christos Exp $"); 42 #endif 43 44 #include <ctype.h> 45 #include <string.h> 46 #include <limits.h> 47 #include <stdlib.h> 48 49 #include "lint2.h" 50 51 static void chkund(hte_t *); 52 static void chkdnu(hte_t *); 53 static void chkdnud(hte_t *); 54 static void chkmd(hte_t *); 55 static void chkvtui(hte_t *, sym_t *, sym_t *); 56 static void chkvtdi(hte_t *, sym_t *, sym_t *); 57 static void chkfaui(hte_t *, sym_t *, sym_t *); 58 static void chkau(hte_t *, int, sym_t *, sym_t *, pos_t *, 59 fcall_t *, fcall_t *, type_t *, type_t *); 60 static void chkrvu(hte_t *, sym_t *); 61 static void chkadecl(hte_t *, sym_t *, sym_t *); 62 static void printflike(hte_t *,fcall_t *, int, const char *, type_t **); 63 static void scanflike(hte_t *, fcall_t *, int, const char *, type_t **); 64 static void badfmt(hte_t *, fcall_t *); 65 static void inconarg(hte_t *, fcall_t *, int); 66 static void tofewarg(hte_t *, fcall_t *); 67 static void tomanyarg(hte_t *, fcall_t *); 68 static int eqtype(type_t *, type_t *, int, int, int, int *); 69 static int eqargs(type_t *, type_t *, int *); 70 static int mnoarg(type_t *, int *); 71 72 73 /* 74 * If there is a symbol named "main", mark it as used. 75 */ 76 void 77 mainused(void) 78 { 79 hte_t *hte; 80 81 if ((hte = hsearch("main", 0)) != NULL) 82 hte->h_used = 1; 83 } 84 85 /* 86 * Performs all tests for a single name 87 */ 88 void 89 chkname(hte_t *hte) 90 { 91 sym_t *sym, *def, *pdecl, *decl; 92 93 if (uflag) { 94 chkund(hte); 95 chkdnu(hte); 96 if (xflag) 97 chkdnud(hte); 98 } 99 chkmd(hte); 100 101 /* Get definition, prototype declaration and declaration */ 102 def = pdecl = decl = NULL; 103 for (sym = hte->h_syms; sym != NULL; sym = sym->s_nxt) { 104 if (def == NULL && (sym->s_def == DEF || sym->s_def == TDEF)) 105 def = sym; 106 if (pdecl == NULL && sym->s_def == DECL && 107 TP(sym->s_type)->t_tspec == FUNC && 108 TP(sym->s_type)->t_proto) { 109 pdecl = sym; 110 } 111 if (decl == NULL && sym->s_def == DECL) 112 decl = sym; 113 } 114 115 /* A prototype is better than an old style declaration. */ 116 if (pdecl != NULL) 117 decl = pdecl; 118 119 chkvtui(hte, def, decl); 120 121 chkvtdi(hte, def, decl); 122 123 chkfaui(hte, def, decl); 124 125 chkrvu(hte, def); 126 127 chkadecl(hte, def, decl); 128 } 129 130 /* 131 * Print a warning if the name has been used, but not defined. 132 */ 133 static void 134 chkund(hte_t *hte) 135 { 136 fcall_t *fcall; 137 usym_t *usym; 138 139 if (!hte->h_used || hte->h_def) 140 return; 141 142 if ((fcall = hte->h_calls) != NULL) { 143 /* %s used( %s ), but not defined */ 144 msg(0, hte->h_name, mkpos(&fcall->f_pos)); 145 } else if ((usym = hte->h_usyms) != NULL) { 146 /* %s used( %s ), but not defined */ 147 msg(0, hte->h_name, mkpos(&usym->u_pos)); 148 } 149 } 150 151 /* 152 * Print a warning if the name has been defined, but never used. 153 */ 154 static void 155 chkdnu(hte_t *hte) 156 { 157 sym_t *sym; 158 159 if (!hte->h_def || hte->h_used) 160 return; 161 162 for (sym = hte->h_syms; sym != NULL; sym = sym->s_nxt) { 163 if (sym->s_def == DEF || sym->s_def == TDEF) { 164 /* %s defined( %s ), but never used */ 165 msg(1, hte->h_name, mkpos(&sym->s_pos)); 166 break; 167 } 168 } 169 } 170 171 /* 172 * Print a warning if the variable has been declared, but is not used 173 * or defined. 174 */ 175 static void 176 chkdnud(hte_t *hte) 177 { 178 sym_t *sym; 179 180 if (hte->h_syms == NULL || hte->h_used || hte->h_def) 181 return; 182 183 sym = hte->h_syms; 184 if (TP(sym->s_type)->t_tspec == FUNC) 185 return; 186 187 if (sym->s_def != DECL) 188 errx(1, "internal error: chkdnud() 1"); 189 /* %s declared( %s ), but never used or defined */ 190 msg(2, hte->h_name, mkpos(&sym->s_pos)); 191 } 192 193 /* 194 * Print a warning if there is more than one definition for 195 * this name. 196 */ 197 static void 198 chkmd(hte_t *hte) 199 { 200 sym_t *sym, *def1; 201 char *pos1; 202 203 if (!hte->h_def) 204 return; 205 206 def1 = NULL; 207 for (sym = hte->h_syms; sym != NULL; sym = sym->s_nxt) { 208 /* 209 * ANSI C allows tentative definitions of the same name in 210 * only one compilation unit. 211 */ 212 if (sym->s_def != DEF && (!sflag || sym->s_def != TDEF)) 213 continue; 214 if (sym->s_inline) 215 continue; 216 if (def1 == NULL) { 217 def1 = sym; 218 continue; 219 } 220 pos1 = xstrdup(mkpos(&def1->s_pos)); 221 /* %s multiply defined\t%s :: %s */ 222 msg(3, hte->h_name, pos1, mkpos(&sym->s_pos)); 223 free(pos1); 224 } 225 } 226 227 /* 228 * Print a warning if the return value assumed for a function call 229 * differs from the return value of the function definition or 230 * function declaration. 231 * 232 * If no definition/declaration can be found, the assumed return values 233 * are always int. So there is no need to compare with another function 234 * call as it's done for function arguments. 235 */ 236 static void 237 chkvtui(hte_t *hte, sym_t *def, sym_t *decl) 238 { 239 fcall_t *call; 240 char *pos1; 241 type_t *tp1, *tp2; 242 int dowarn, eq; 243 tspec_t t1; 244 245 if (hte->h_calls == NULL) 246 return; 247 248 if (def == NULL) 249 def = decl; 250 if (def == NULL) 251 return; 252 253 t1 = (tp1 = TP(def->s_type)->t_subt)->t_tspec; 254 for (call = hte->h_calls; call != NULL; call = call->f_nxt) { 255 tp2 = TP(call->f_type)->t_subt; 256 eq = eqtype(tp1, tp2, 1, 0, 0, (dowarn = 0, &dowarn)); 257 if (!call->f_rused) { 258 /* no return value used */ 259 if ((t1 == STRUCT || t1 == UNION) && !eq) { 260 /* 261 * If a function returns a struct or union it 262 * must be declared to return a struct or 263 * union, also if the return value is ignored. 264 * This is necessary because the caller must 265 * allocate stack space for the return value. 266 * If it does not, the return value would over- 267 * write other data. 268 * XXX Following massage may be confusing 269 * because it appears also if the return value 270 * was declared inconsistently. But this 271 * behaviour matches pcc based lint, so it is 272 * accepted for now. 273 */ 274 pos1 = xstrdup(mkpos(&def->s_pos)); 275 /* %s value must be decl. before use %s :: %s */ 276 msg(17, hte->h_name, 277 pos1, mkpos(&call->f_pos)); 278 free(pos1); 279 } 280 continue; 281 } 282 if (!eq || (sflag && dowarn)) { 283 pos1 = xstrdup(mkpos(&def->s_pos)); 284 /* %s value used inconsistenty\t%s :: %s */ 285 msg(4, hte->h_name, pos1, mkpos(&call->f_pos)); 286 free(pos1); 287 } 288 } 289 } 290 291 /* 292 * Print a warning if a definition/declaration does not match another 293 * definition/declaration of the same name. For functions, only the 294 * types of return values are tested. 295 */ 296 static void 297 chkvtdi(hte_t *hte, sym_t *def, sym_t *decl) 298 { 299 sym_t *sym; 300 type_t *tp1, *tp2; 301 int eq, dowarn; 302 char *pos1; 303 304 if (def == NULL) 305 def = decl; 306 if (def == NULL) 307 return; 308 309 tp1 = TP(def->s_type); 310 for (sym = hte->h_syms; sym != NULL; sym = sym->s_nxt) { 311 type_t *xt1, *xt2; 312 if (sym == def) 313 continue; 314 tp2 = TP(sym->s_type); 315 dowarn = 0; 316 if (tp1->t_tspec == FUNC && tp2->t_tspec == FUNC) { 317 eq = eqtype(xt1 = tp1->t_subt, xt2 = tp2->t_subt, 318 1, 0, 0, &dowarn); 319 } else { 320 eq = eqtype(xt1 = tp1, xt2 = tp2, 0, 0, 0, &dowarn); 321 } 322 if (!eq || (sflag && dowarn)) { 323 char b1[64], b2[64]; 324 pos1 = xstrdup(mkpos(&def->s_pos)); 325 /* %s value declared inconsistently\t%s :: %s */ 326 msg(5, hte->h_name, tyname(b1, sizeof(b1), xt1), 327 tyname(b2, sizeof(b2), xt2), pos1, 328 mkpos(&sym->s_pos)); 329 free(pos1); 330 } 331 } 332 } 333 334 /* 335 * Print a warning if a function is called with arguments which does 336 * not match the function definition, declaration or another call 337 * of the same function. 338 */ 339 static void 340 chkfaui(hte_t *hte, sym_t *def, sym_t *decl) 341 { 342 type_t *tp1, *tp2, **ap1, **ap2; 343 pos_t *pos1p = NULL; 344 fcall_t *calls, *call, *call1; 345 int n, as; 346 char *pos1; 347 arginf_t *ai; 348 349 if ((calls = hte->h_calls) == NULL) 350 return; 351 352 /* 353 * If we find a function definition, we use this for comparison, 354 * otherwise the first prototype we can find. If there is no 355 * definition or prototype declaration, the first function call 356 * is used. 357 */ 358 tp1 = NULL; 359 call1 = NULL; 360 if (def != NULL) { 361 if ((tp1 = TP(def->s_type))->t_tspec != FUNC) 362 return; 363 pos1p = &def->s_pos; 364 } else if (decl != NULL && TP(decl->s_type)->t_proto) { 365 if ((tp1 = TP(decl->s_type))->t_tspec != FUNC) 366 return; 367 pos1p = &decl->s_pos; 368 } 369 if (tp1 == NULL) { 370 call1 = calls; 371 calls = calls->f_nxt; 372 if ((tp1 = TP(call1->f_type))->t_tspec != FUNC) 373 return; 374 pos1p = &call1->f_pos; 375 } 376 377 n = 1; 378 for (call = calls; call != NULL; call = call->f_nxt) { 379 if ((tp2 = TP(call->f_type))->t_tspec != FUNC) 380 continue; 381 ap1 = tp1->t_args; 382 ap2 = tp2->t_args; 383 n = 0; 384 while (*ap1 != NULL && *ap2 != NULL) { 385 if (def != NULL && def->s_va && n >= def->s_nva) 386 break; 387 n++; 388 chkau(hte, n, def, decl, pos1p, call1, call, 389 *ap1, *ap2); 390 ap1++; 391 ap2++; 392 } 393 if (*ap1 == *ap2) { 394 /* equal # of arguments */ 395 } else if (def != NULL && def->s_va && n >= def->s_nva) { 396 /* 397 * function definition with VARARGS; The # of 398 * arguments of the call must be at least as large 399 * as the parameter of VARARGS. 400 */ 401 } else if (*ap2 != NULL && tp1->t_proto && tp1->t_vararg) { 402 /* 403 * prototype with ... and function call with 404 * at least the same # of arguments as declared 405 * in the prototype. 406 */ 407 } else { 408 pos1 = xstrdup(mkpos(pos1p)); 409 /* %s: variable # of args\t%s :: %s */ 410 msg(7, hte->h_name, pos1, mkpos(&call->f_pos)); 411 free(pos1); 412 continue; 413 } 414 415 /* perform SCANFLIKE/PRINTFLIKE tests */ 416 if (def == NULL || (!def->s_prfl && !def->s_scfl)) 417 continue; 418 as = def->s_prfl ? def->s_nprfl : def->s_nscfl; 419 for (ai = call->f_args; ai != NULL; ai = ai->a_nxt) { 420 if (ai->a_num == as) 421 break; 422 } 423 if (ai == NULL || !ai->a_fmt) 424 continue; 425 if (def->s_prfl) { 426 printflike(hte, call, n, ai->a_fstrg, ap2); 427 } else { 428 scanflike(hte, call, n, ai->a_fstrg, ap2); 429 } 430 } 431 } 432 433 /* 434 * Check a single argument in a function call. 435 * 436 * hte a pointer to the hash table entry of the function 437 * n the number of the argument (1..) 438 * def the function definition or NULL 439 * decl prototype declaration, old style declaration or NULL 440 * pos1p position of definition, declaration of first call 441 * call1 first call, if both def and decl are old style def/decl 442 * call checked call 443 * arg1 currently checked argument of def/decl/call1 444 * arg2 currently checked argument of call 445 * 446 */ 447 static void 448 chkau(hte_t *hte, int n, sym_t *def, sym_t *decl, pos_t *pos1p, 449 fcall_t *call1, fcall_t *call, type_t *arg1, type_t *arg2) 450 { 451 int promote, asgn, dowarn; 452 tspec_t t1, t2; 453 arginf_t *ai, *ai1; 454 char *pos1; 455 char tyname1[64], tyname2[64]; 456 457 /* 458 * If a function definition is available (def != NULL), we compair the 459 * function call (call) with the definition. Otherwise, if a function 460 * definition is available and it is not an old style definition 461 * (decl != NULL && TP(decl->s_type)->t_proto), we compair the call 462 * with this declaration. Otherwise we compair it with the first 463 * call we have found (call1). 464 */ 465 466 /* arg1 must be promoted if it stems from an old style definition */ 467 promote = def != NULL && def->s_osdef; 468 469 /* 470 * If we compair with a definition or declaration, we must perform 471 * the same checks for qualifiers in indirected types as in 472 * assignments. 473 */ 474 asgn = def != NULL || (decl != NULL && TP(decl->s_type)->t_proto); 475 476 dowarn = 0; 477 if (eqtype(arg1, arg2, 1, promote, asgn, &dowarn) && (!sflag || !dowarn)) 478 return; 479 480 /* 481 * Other lint implementations print warnings as soon as the type 482 * of an argument does not match exactly the expected type. The 483 * result are lots of warnings which are really not necessary. 484 * We print a warning only if 485 * (0) at least one type is not an interger type and types differ 486 * (1) hflag is set and types differ 487 * (2) types differ, except in signedness 488 * If the argument is an integer constant whose msb is not set, 489 * signedness is ignored (e.g. 0 matches both signed and unsigned 490 * int). This is with and without hflag. 491 * If the argument is an integer constant with value 0 and the 492 * expected argument is of type pointer and the width of the 493 * interger constant is the same as the width of the pointer, 494 * no warning is printed. 495 */ 496 t1 = arg1->t_tspec; 497 t2 = arg2->t_tspec; 498 if (isityp(t1) && isityp(t2) && !arg1->t_isenum && !arg2->t_isenum) { 499 if (promote) { 500 /* 501 * XXX Here is a problem: Althrough it is possible to 502 * pass an int where a char/short it expected, there 503 * may be loss in significant digits. We should first 504 * check for const arguments if they can be converted 505 * into the original parameter type. 506 */ 507 if (t1 == FLOAT) { 508 t1 = DOUBLE; 509 } else if (t1 == CHAR || t1 == SCHAR) { 510 t1 = INT; 511 } else if (t1 == UCHAR) { 512 t1 = tflag ? UINT : INT; 513 } else if (t1 == SHORT) { 514 t1 = INT; 515 } else if (t1 == USHORT) { 516 /* CONSTCOND */ 517 t1 = INT_MAX < USHRT_MAX || tflag ? UINT : INT; 518 } 519 } 520 521 if (styp(t1) == styp(t2)) { 522 523 /* 524 * types differ only in signedness; get information 525 * about arguments 526 */ 527 528 /* 529 * treat a definition like a call with variable 530 * arguments 531 */ 532 ai1 = call1 != NULL ? call1->f_args : NULL; 533 534 /* 535 * if two calls are compared, ai1 is set to the 536 * information for the n-th argument, if this was 537 * a constant, otherwise to NULL 538 */ 539 for ( ; ai1 != NULL; ai1 = ai1->a_nxt) { 540 if (ai1->a_num == n) 541 break; 542 } 543 /* 544 * ai is set to the information of the n-th arg 545 * of the (second) call, if this was a constant, 546 * otherwise to NULL 547 */ 548 for (ai = call->f_args; ai != NULL; ai = ai->a_nxt) { 549 if (ai->a_num == n) 550 break; 551 } 552 553 if (ai1 == NULL && ai == NULL) { 554 /* no constant at all */ 555 if (!hflag) 556 return; 557 } else if (ai1 == NULL || ai == NULL) { 558 /* one constant */ 559 if (ai == NULL) 560 ai = ai1; 561 if (ai->a_zero || ai->a_pcon) 562 /* same value in signed and unsigned */ 563 return; 564 /* value (not representation) differently */ 565 } else { 566 /* 567 * two constants, one signed, one unsigned; 568 * if the msb of one of the constants is set, 569 * the argument is used inconsistently. 570 */ 571 if (!ai1->a_ncon && !ai->a_ncon) 572 return; 573 } 574 } 575 576 } else if (t1 == PTR && isityp(t2)) { 577 for (ai = call->f_args; ai != NULL; ai = ai->a_nxt) { 578 if (ai->a_num == n) 579 break; 580 } 581 /* 582 * Vendor implementations of lint (e.g. HP-UX, Digital UNIX) 583 * don't care about the size of the integer argument, 584 * only whether or not it is zero. We do the same. 585 */ 586 if (ai != NULL && ai->a_zero) 587 return; 588 } 589 590 pos1 = xstrdup(mkpos(pos1p)); 591 /* %s, arg %d used inconsistently\t%s[%s] :: %s[%s] */ 592 msg(6, hte->h_name, n, pos1, 593 tyname(tyname1, sizeof(tyname1), arg1), 594 mkpos(&call->f_pos), 595 tyname(tyname2, sizeof(tyname2), arg2)); 596 free(pos1); 597 } 598 599 /* 600 * Compare the types in the NULL-terminated array ap with the format 601 * string fmt. 602 */ 603 static void 604 printflike(hte_t *hte, fcall_t *call, int n, const char *fmt, type_t **ap) 605 { 606 const char *fp; 607 int fc; 608 int fwidth, prec, left, sign, space, alt, zero; 609 tspec_t sz, t1, t2 = NOTSPEC; 610 type_t *tp; 611 612 fp = fmt; 613 fc = *fp++; 614 615 for ( ; ; ) { 616 if (fc == '\0') { 617 if (*ap != NULL) 618 tomanyarg(hte, call); 619 break; 620 } 621 if (fc != '%') { 622 badfmt(hte, call); 623 break; 624 } 625 fc = *fp++; 626 fwidth = prec = left = sign = space = alt = zero = 0; 627 sz = NOTSPEC; 628 629 /* Flags */ 630 for ( ; ; ) { 631 if (fc == '-') { 632 if (left) 633 break; 634 left = 1; 635 } else if (fc == '+') { 636 if (sign) 637 break; 638 sign = 1; 639 } else if (fc == ' ') { 640 if (space) 641 break; 642 space = 1; 643 } else if (fc == '#') { 644 if (alt) 645 break; 646 alt = 1; 647 } else if (fc == '0') { 648 if (zero) 649 break; 650 zero = 1; 651 } else { 652 break; 653 } 654 fc = *fp++; 655 } 656 657 /* field width */ 658 if (isdigit(fc)) { 659 fwidth = 1; 660 do { fc = *fp++; } while (isdigit(fc)) ; 661 } else if (fc == '*') { 662 fwidth = 1; 663 fc = *fp++; 664 if ((tp = *ap++) == NULL) { 665 tofewarg(hte, call); 666 break; 667 } 668 n++; 669 if ((t1 = tp->t_tspec) != INT && (hflag || t1 != UINT)) 670 inconarg(hte, call, n); 671 } 672 673 /* precision */ 674 if (fc == '.') { 675 fc = *fp++; 676 prec = 1; 677 if (isdigit(fc)) { 678 do { fc = *fp++; } while (isdigit(fc)); 679 } else if (fc == '*') { 680 fc = *fp++; 681 if ((tp = *ap++) == NULL) { 682 tofewarg(hte, call); 683 break; 684 } 685 n++; 686 if (tp->t_tspec != INT) 687 inconarg(hte, call, n); 688 } else { 689 badfmt(hte, call); 690 break; 691 } 692 } 693 694 if (fc == 'h') { 695 sz = SHORT; 696 } else if (fc == 'l') { 697 sz = LONG; 698 } else if (fc == 'q') { 699 sz = QUAD; 700 } else if (fc == 'L') { 701 sz = LDOUBLE; 702 } 703 if (sz != NOTSPEC) 704 fc = *fp++; 705 706 if (fc == '%') { 707 if (sz != NOTSPEC || left || sign || space || 708 alt || zero || prec || fwidth) { 709 badfmt(hte, call); 710 } 711 fc = *fp++; 712 continue; 713 } 714 715 if (fc == '\0') { 716 badfmt(hte, call); 717 break; 718 } 719 720 if ((tp = *ap++) == NULL) { 721 tofewarg(hte, call); 722 break; 723 } 724 n++; 725 if ((t1 = tp->t_tspec) == PTR) 726 t2 = tp->t_subt->t_tspec; 727 728 if (fc == 'd' || fc == 'i') { 729 if (alt || sz == LDOUBLE) { 730 badfmt(hte, call); 731 break; 732 } 733 int_conv: 734 if (sz == LONG) { 735 if (t1 != LONG && (hflag || t1 != ULONG)) 736 inconarg(hte, call, n); 737 } else if (sz == QUAD) { 738 if (t1 != QUAD && (hflag || t1 != UQUAD)) 739 inconarg(hte, call, n); 740 } else { 741 /* 742 * SHORT is always promoted to INT, USHORT 743 * to INT or UINT. 744 */ 745 if (t1 != INT && (hflag || t1 != UINT)) 746 inconarg(hte, call, n); 747 } 748 } else if (fc == 'o' || fc == 'u' || fc == 'x' || fc == 'X') { 749 if ((alt && fc == 'u') || sz == LDOUBLE) 750 badfmt(hte, call); 751 uint_conv: 752 if (sz == LONG) { 753 if (t1 != ULONG && (hflag || t1 != LONG)) 754 inconarg(hte, call, n); 755 } else if (sz == QUAD) { 756 if (t1 != UQUAD && (hflag || t1 != QUAD)) 757 inconarg(hte, call, n); 758 } else if (sz == SHORT) { 759 /* USHORT was promoted to INT or UINT */ 760 if (t1 != UINT && t1 != INT) 761 inconarg(hte, call, n); 762 } else { 763 if (t1 != UINT && (hflag || t1 != INT)) 764 inconarg(hte, call, n); 765 } 766 } else if (fc == 'D' || fc == 'O' || fc == 'U') { 767 if ((alt && fc != 'O') || sz != NOTSPEC || !tflag) 768 badfmt(hte, call); 769 sz = LONG; 770 if (fc == 'D') { 771 goto int_conv; 772 } else { 773 goto uint_conv; 774 } 775 } else if (fc == 'f' || fc == 'e' || fc == 'E' || 776 fc == 'g' || fc == 'G') { 777 if (sz == NOTSPEC) 778 sz = DOUBLE; 779 if (sz != DOUBLE && sz != LDOUBLE) 780 badfmt(hte, call); 781 if (t1 != sz) 782 inconarg(hte, call, n); 783 } else if (fc == 'c') { 784 if (sz != NOTSPEC || alt || zero) 785 badfmt(hte, call); 786 if (t1 != INT) 787 inconarg(hte, call, n); 788 } else if (fc == 's') { 789 if (sz != NOTSPEC || alt || zero) 790 badfmt(hte, call); 791 if (t1 != PTR || 792 (t2 != CHAR && t2 != UCHAR && t2 != SCHAR)) { 793 inconarg(hte, call, n); 794 } 795 } else if (fc == 'p') { 796 if (fwidth || prec || sz != NOTSPEC || alt || zero) 797 badfmt(hte, call); 798 if (t1 != PTR || (hflag && t2 != VOID)) 799 inconarg(hte, call, n); 800 } else if (fc == 'n') { 801 if (fwidth || prec || alt || zero || sz == LDOUBLE) 802 badfmt(hte, call); 803 if (t1 != PTR) { 804 inconarg(hte, call, n); 805 } else if (sz == LONG) { 806 if (t2 != LONG && t2 != ULONG) 807 inconarg(hte, call, n); 808 } else if (sz == SHORT) { 809 if (t2 != SHORT && t2 != USHORT) 810 inconarg(hte, call, n); 811 } else { 812 if (t2 != INT && t2 != UINT) 813 inconarg(hte, call, n); 814 } 815 } else { 816 badfmt(hte, call); 817 break; 818 } 819 820 fc = *fp++; 821 } 822 } 823 824 /* 825 * Compare the types in the NULL-terminated array ap with the format 826 * string fmt. 827 */ 828 static void 829 scanflike(hte_t *hte, fcall_t *call, int n, const char *fmt, type_t **ap) 830 { 831 const char *fp; 832 int fc; 833 int noasgn, fwidth; 834 tspec_t sz, t1 = NOTSPEC, t2 = NOTSPEC; 835 type_t *tp = NULL; 836 837 fp = fmt; 838 fc = *fp++; 839 840 for ( ; ; ) { 841 if (fc == '\0') { 842 if (*ap != NULL) 843 tomanyarg(hte, call); 844 break; 845 } 846 if (fc != '%') { 847 badfmt(hte, call); 848 break; 849 } 850 fc = *fp++; 851 852 noasgn = fwidth = 0; 853 sz = NOTSPEC; 854 855 if (fc == '*') { 856 noasgn = 1; 857 fc = *fp++; 858 } 859 860 if (isdigit(fc)) { 861 fwidth = 1; 862 do { fc = *fp++; } while (isdigit(fc)); 863 } 864 865 if (fc == 'h') { 866 sz = SHORT; 867 } else if (fc == 'l') { 868 sz = LONG; 869 } else if (fc == 'q') { 870 sz = QUAD; 871 } else if (fc == 'L') { 872 sz = LDOUBLE; 873 } 874 if (sz != NOTSPEC) 875 fc = *fp++; 876 877 if (fc == '%') { 878 if (sz != NOTSPEC || noasgn || fwidth) 879 badfmt(hte, call); 880 fc = *fp++; 881 continue; 882 } 883 884 if (!noasgn) { 885 if ((tp = *ap++) == NULL) { 886 tofewarg(hte, call); 887 break; 888 } 889 n++; 890 if ((t1 = tp->t_tspec) == PTR) 891 t2 = tp->t_subt->t_tspec; 892 } 893 894 if (fc == 'd' || fc == 'i' || fc == 'n') { 895 if (sz == LDOUBLE) 896 badfmt(hte, call); 897 if (sz != SHORT && sz != LONG && sz != QUAD) 898 sz = INT; 899 conv: 900 if (!noasgn) { 901 if (t1 != PTR) { 902 inconarg(hte, call, n); 903 } else if (t2 != styp(sz)) { 904 inconarg(hte, call, n); 905 } else if (hflag && t2 != sz) { 906 inconarg(hte, call, n); 907 } else if (tp->t_subt->t_const) { 908 inconarg(hte, call, n); 909 } 910 } 911 } else if (fc == 'o' || fc == 'u' || fc == 'x') { 912 if (sz == LDOUBLE) 913 badfmt(hte, call); 914 if (sz == SHORT) { 915 sz = USHORT; 916 } else if (sz == LONG) { 917 sz = ULONG; 918 } else if (sz == QUAD) { 919 sz = UQUAD; 920 } else { 921 sz = UINT; 922 } 923 goto conv; 924 } else if (fc == 'D') { 925 if (sz != NOTSPEC || !tflag) 926 badfmt(hte, call); 927 sz = LONG; 928 goto conv; 929 } else if (fc == 'O') { 930 if (sz != NOTSPEC || !tflag) 931 badfmt(hte, call); 932 sz = ULONG; 933 goto conv; 934 } else if (fc == 'X') { 935 /* 936 * XXX valid in ANSI C, but in NetBSD's libc imple- 937 * mented as "lx". Thats why it should be avoided. 938 */ 939 if (sz != NOTSPEC || !tflag) 940 badfmt(hte, call); 941 sz = ULONG; 942 goto conv; 943 } else if (fc == 'E') { 944 /* 945 * XXX valid in ANSI C, but in NetBSD's libc imple- 946 * mented as "lf". Thats why it should be avoided. 947 */ 948 if (sz != NOTSPEC || !tflag) 949 badfmt(hte, call); 950 sz = DOUBLE; 951 goto conv; 952 } else if (fc == 'F') { 953 /* XXX only for backward compatibility */ 954 if (sz != NOTSPEC || !tflag) 955 badfmt(hte, call); 956 sz = DOUBLE; 957 goto conv; 958 } else if (fc == 'G') { 959 /* 960 * XXX valid in ANSI C, but in NetBSD's libc not 961 * implemented 962 */ 963 if (sz != NOTSPEC && sz != LONG && sz != LDOUBLE) 964 badfmt(hte, call); 965 goto fconv; 966 } else if (fc == 'e' || fc == 'f' || fc == 'g') { 967 fconv: 968 if (sz == NOTSPEC) { 969 sz = FLOAT; 970 } else if (sz == LONG) { 971 sz = DOUBLE; 972 } else if (sz != LDOUBLE) { 973 badfmt(hte, call); 974 sz = FLOAT; 975 } 976 goto conv; 977 } else if (fc == 's' || fc == '[' || fc == 'c') { 978 if (sz != NOTSPEC) 979 badfmt(hte, call); 980 if (fc == '[') { 981 if ((fc = *fp++) == '-') { 982 badfmt(hte, call); 983 fc = *fp++; 984 } 985 if (fc != ']') { 986 badfmt(hte, call); 987 if (fc == '\0') 988 break; 989 } 990 } 991 if (!noasgn) { 992 if (t1 != PTR) { 993 inconarg(hte, call, n); 994 } else if (t2 != CHAR && t2 != UCHAR && 995 t2 != SCHAR) { 996 inconarg(hte, call, n); 997 } 998 } 999 } else if (fc == 'p') { 1000 if (sz != NOTSPEC) 1001 badfmt(hte, call); 1002 if (!noasgn) { 1003 if (t1 != PTR || t2 != PTR) { 1004 inconarg(hte, call, n); 1005 } else if (tp->t_subt->t_subt->t_tspec!=VOID) { 1006 if (hflag) 1007 inconarg(hte, call, n); 1008 } 1009 } 1010 } else { 1011 badfmt(hte, call); 1012 break; 1013 } 1014 1015 fc = *fp++; 1016 } 1017 } 1018 1019 static void 1020 badfmt(hte_t *hte, fcall_t *call) 1021 { 1022 1023 /* %s: malformed format string\t%s */ 1024 msg(13, hte->h_name, mkpos(&call->f_pos)); 1025 } 1026 1027 static void 1028 inconarg(hte_t *hte, fcall_t *call, int n) 1029 { 1030 1031 /* %s, arg %d inconsistent with format\t%s(%d) */ 1032 msg(14, hte->h_name, n, mkpos(&call->f_pos)); 1033 } 1034 1035 static void 1036 tofewarg(hte_t *hte, fcall_t *call) 1037 { 1038 1039 /* %s: too few args for format \t%s */ 1040 msg(15, hte->h_name, mkpos(&call->f_pos)); 1041 } 1042 1043 static void 1044 tomanyarg(hte_t *hte, fcall_t *call) 1045 { 1046 1047 /* %s: too many args for format \t%s */ 1048 msg(16, hte->h_name, mkpos(&call->f_pos)); 1049 } 1050 1051 /* 1052 * List of functions where we usually don't care about their result. 1053 * NB: Must be sorted. 1054 */ 1055 static const char ignorelist[][8] = { 1056 "memcpy", 1057 "memmove", 1058 "memset", 1059 "printf", 1060 "strcat", 1061 "strcpy", 1062 "vprintf", 1063 }; 1064 1065 /* 1066 * Print warnings for return values which are used, but not returned, 1067 * or return values which are always or sometimes ignored. 1068 */ 1069 static void 1070 chkrvu(hte_t *hte, sym_t *def) 1071 { 1072 fcall_t *call; 1073 int used, ignored; 1074 1075 if (def == NULL) 1076 /* don't know whether or not the functions returns a value */ 1077 return; 1078 1079 if (hte->h_calls == NULL) 1080 return; 1081 1082 if (def->s_rval) { 1083 /* 1084 * XXX as soon as we are able to disable single warnings 1085 * the following dependencies from hflag should be removed. 1086 * but for now I do'nt want to be botherd by this warnings 1087 * which are almost always useless. 1088 */ 1089 if (hflag == 0) 1090 return; 1091 if (hflag == 1 && bsearch(hte->h_name, ignorelist, 1092 __arraycount(ignorelist), sizeof(ignorelist[0]), 1093 (int (*)(const void *, const void *))strcmp) != NULL) 1094 return; 1095 1096 /* function has return value */ 1097 used = ignored = 0; 1098 for (call = hte->h_calls; call != NULL; call = call->f_nxt) { 1099 used |= call->f_rused || call->f_rdisc; 1100 ignored |= !call->f_rused && !call->f_rdisc; 1101 } 1102 if (!used && ignored) { 1103 /* %s returns value which is always ignored */ 1104 msg(8, hte->h_name); 1105 } else if (used && ignored) { 1106 /* %s returns value which is sometimes ign. */ 1107 msg(9, hte->h_name); 1108 } 1109 } else { 1110 /* function has no return value */ 1111 for (call = hte->h_calls; call != NULL; call = call->f_nxt) { 1112 if (call->f_rused) 1113 /* %s value is used( %s ), but none ret. */ 1114 msg(10, hte->h_name, mkpos(&call->f_pos)); 1115 } 1116 } 1117 } 1118 1119 /* 1120 * Print warnings for inconsistent argument declarations. 1121 */ 1122 static void 1123 chkadecl(hte_t *hte, sym_t *def, sym_t *decl) 1124 { 1125 int osdef, eq, dowarn, n; 1126 sym_t *sym1, *sym; 1127 type_t **ap1, **ap2, *tp1, *tp2; 1128 char *pos1; 1129 const char *pos2; 1130 1131 osdef = 0; 1132 if (def != NULL) { 1133 osdef = def->s_osdef; 1134 sym1 = def; 1135 } else if (decl != NULL && TP(decl->s_type)->t_proto) { 1136 sym1 = decl; 1137 } else { 1138 return; 1139 } 1140 if (TP(sym1->s_type)->t_tspec != FUNC) 1141 return; 1142 1143 /* 1144 * XXX Prototypes should also be compared with old style function 1145 * declarations. 1146 */ 1147 1148 for (sym = hte->h_syms; sym != NULL; sym = sym->s_nxt) { 1149 if (sym == sym1 || !TP(sym->s_type)->t_proto) 1150 continue; 1151 ap1 = TP(sym1->s_type)->t_args; 1152 ap2 = TP(sym->s_type)->t_args; 1153 n = 0; 1154 while (*ap1 != NULL && *ap2 != NULL) { 1155 type_t *xt1, *xt2; 1156 dowarn = 0; 1157 eq = eqtype(xt1 = *ap1, xt2 = *ap2, 1, osdef, 0, &dowarn); 1158 if (!eq || dowarn) { 1159 char b1[64], b2[64]; 1160 pos1 = xstrdup(mkpos(&sym1->s_pos)); 1161 pos2 = mkpos(&sym->s_pos); 1162 /* %s, arg %d declared inconsistently ... */ 1163 msg(11, hte->h_name, n + 1, 1164 tyname(b1, sizeof(b1), xt1), 1165 tyname(b2, sizeof(b2), xt2), pos1, pos2); 1166 free(pos1); 1167 } 1168 n++; 1169 ap1++; 1170 ap2++; 1171 } 1172 if (*ap1 == *ap2) { 1173 tp1 = TP(sym1->s_type); 1174 tp2 = TP(sym->s_type); 1175 if (tp1->t_vararg == tp2->t_vararg) 1176 continue; 1177 if (tp2->t_vararg && 1178 sym1->s_va && sym1->s_nva == n && !sflag) { 1179 continue; 1180 } 1181 } 1182 /* %s: variable # of args declared\t%s :: %s */ 1183 pos1 = xstrdup(mkpos(&sym1->s_pos)); 1184 msg(12, hte->h_name, pos1, mkpos(&sym->s_pos)); 1185 free(pos1); 1186 } 1187 } 1188 1189 1190 /* 1191 * Check compatibility of two types. Returns 1 if types are compatible, 1192 * otherwise 0. 1193 * 1194 * ignqual if set, ignore qualifiers of outhermost type; used for 1195 * function arguments 1196 * promote if set, promote left type before comparison; used for 1197 * comparisons of arguments with parameters of old style 1198 * definitions 1199 * asgn left indirected type must have at least the same qualifiers 1200 * like right indirected type (for assignments and function 1201 * arguments) 1202 * *dowarn set to 1 if an old style declaration was compared with 1203 * an incompatible prototype declaration 1204 */ 1205 static int 1206 eqtype(type_t *tp1, type_t *tp2, int ignqual, int promot, int asgn, int *dowarn) 1207 { 1208 tspec_t t, to; 1209 int indir; 1210 1211 to = NOTSPEC; 1212 indir = 0; 1213 1214 while (tp1 != NULL && tp2 != NULL) { 1215 1216 t = tp1->t_tspec; 1217 if (promot) { 1218 if (t == FLOAT) { 1219 t = DOUBLE; 1220 } else if (t == CHAR || t == SCHAR) { 1221 t = INT; 1222 } else if (t == UCHAR) { 1223 t = tflag ? UINT : INT; 1224 } else if (t == SHORT) { 1225 t = INT; 1226 } else if (t == USHORT) { 1227 /* CONSTCOND */ 1228 t = INT_MAX < USHRT_MAX || tflag ? UINT : INT; 1229 } 1230 } 1231 1232 if (asgn && to == PTR) { 1233 if (indir == 1 && (t == VOID || tp2->t_tspec == VOID)) 1234 return (1); 1235 } 1236 1237 if (t != tp2->t_tspec) { 1238 /* 1239 * Give pointer to types which differ only in 1240 * signedness a chance if not sflag and not hflag. 1241 */ 1242 if (sflag || hflag || to != PTR) 1243 return (0); 1244 if (styp(t) != styp(tp2->t_tspec)) 1245 return (0); 1246 } 1247 1248 if (tp1->t_isenum && tp2->t_isenum) { 1249 if (tp1->t_istag && tp2->t_istag) { 1250 return (tp1->t_tag == tp2->t_tag); 1251 } else if (tp1->t_istynam && tp2->t_istynam) { 1252 return (tp1->t_tynam == tp2->t_tynam); 1253 } else if (tp1->t_isuniqpos && tp2->t_isuniqpos) { 1254 return (tp1->t_uniqpos.p_line == 1255 tp2->t_uniqpos.p_line && 1256 tp1->t_uniqpos.p_file == 1257 tp2->t_uniqpos.p_file && 1258 tp1->t_uniqpos.p_uniq == 1259 tp2->t_uniqpos.p_uniq); 1260 } else { 1261 return (0); 1262 } 1263 } 1264 1265 /* 1266 * XXX Handle combinations of enum and int if eflag is set. 1267 * But note: enum and 0 should be allowed. 1268 */ 1269 1270 if (asgn && indir == 1) { 1271 if (!tp1->t_const && tp2->t_const) 1272 return (0); 1273 if (!tp1->t_volatile && tp2->t_volatile) 1274 return (0); 1275 } else if (!ignqual && !tflag) { 1276 if (tp1->t_const != tp2->t_const) 1277 return (0); 1278 if (tp1->t_const != tp2->t_const) 1279 return (0); 1280 } 1281 1282 if (t == STRUCT || t == UNION) { 1283 if (tp1->t_istag && tp2->t_istag) { 1284 return (tp1->t_tag == tp2->t_tag); 1285 } else if (tp1->t_istynam && tp2->t_istynam) { 1286 return (tp1->t_tynam == tp2->t_tynam); 1287 } else if (tp1->t_isuniqpos && tp2->t_isuniqpos) { 1288 return (tp1->t_uniqpos.p_line == 1289 tp2->t_uniqpos.p_line && 1290 tp1->t_uniqpos.p_file == 1291 tp2->t_uniqpos.p_file && 1292 tp1->t_uniqpos.p_uniq == 1293 tp2->t_uniqpos.p_uniq); 1294 } else { 1295 return (0); 1296 } 1297 } 1298 1299 if (t == ARRAY && tp1->t_dim != tp2->t_dim) { 1300 if (tp1->t_dim != 0 && tp2->t_dim != 0) 1301 return (0); 1302 } 1303 1304 if (t == FUNC) { 1305 if (tp1->t_proto && tp2->t_proto) { 1306 if (!eqargs(tp1, tp2, dowarn)) 1307 return (0); 1308 } else if (tp1->t_proto) { 1309 if (!mnoarg(tp1, dowarn)) 1310 return (0); 1311 } else if (tp2->t_proto) { 1312 if (!mnoarg(tp2, dowarn)) 1313 return (0); 1314 } 1315 } 1316 1317 tp1 = tp1->t_subt; 1318 tp2 = tp2->t_subt; 1319 ignqual = promot = 0; 1320 to = t; 1321 indir++; 1322 1323 } 1324 1325 return (tp1 == tp2); 1326 } 1327 1328 /* 1329 * Compares arguments of two prototypes 1330 */ 1331 static int 1332 eqargs(type_t *tp1, type_t *tp2, int *dowarn) 1333 { 1334 type_t **a1, **a2; 1335 1336 if (tp1->t_vararg != tp2->t_vararg) 1337 return (0); 1338 1339 a1 = tp1->t_args; 1340 a2 = tp2->t_args; 1341 1342 while (*a1 != NULL && *a2 != NULL) { 1343 1344 if (eqtype(*a1, *a2, 1, 0, 0, dowarn) == 0) 1345 return (0); 1346 1347 a1++; 1348 a2++; 1349 1350 } 1351 1352 return (*a1 == *a2); 1353 } 1354 1355 /* 1356 * mnoarg() (matches functions with no argument type information) 1357 * returns 1 if all parameters of a prototype are compatible with 1358 * and old style function declaration. 1359 * This is the case if following conditions are met: 1360 * 1. the prototype must have a fixed number of parameters 1361 * 2. no parameter is of type float 1362 * 3. no parameter is converted to another type if integer promotion 1363 * is applied on it 1364 */ 1365 static int 1366 mnoarg(type_t *tp, int *dowarn) 1367 { 1368 type_t **arg; 1369 tspec_t t; 1370 1371 if (tp->t_vararg && dowarn != NULL) 1372 *dowarn = 1; 1373 for (arg = tp->t_args; *arg != NULL; arg++) { 1374 if ((t = (*arg)->t_tspec) == FLOAT) 1375 return (0); 1376 if (t == CHAR || t == SCHAR || t == UCHAR) 1377 return (0); 1378 if (t == SHORT || t == USHORT) 1379 return (0); 1380 } 1381 return (1); 1382 } 1383