chk.c revision 1.45
1 /* $NetBSD: chk.c,v 1.45 2021/08/29 10:13:02 rillig 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 1.45 2021/08/29 10:13:02 rillig Exp $"); 42 #endif 43 44 #include <ctype.h> 45 #include <limits.h> 46 #include <stdlib.h> 47 #include <string.h> 48 49 #include "lint2.h" 50 51 static void chkund(const hte_t *); 52 static void chkdnu(const hte_t *); 53 static void chkdnud(const hte_t *); 54 static void chkmd(const hte_t *); 55 static void chkvtui(const hte_t *, sym_t *, sym_t *); 56 static void chkvtdi(const hte_t *, sym_t *, sym_t *); 57 static void chkfaui(const hte_t *, sym_t *, sym_t *); 58 static void chkau(const hte_t *, int, sym_t *, sym_t *, pos_t *, 59 fcall_t *, fcall_t *, type_t *, type_t *); 60 static void chkrvu(const hte_t *, sym_t *); 61 static void chkadecl(const hte_t *, sym_t *, sym_t *); 62 static void printflike(const hte_t *, fcall_t *, int, const char *, type_t **); 63 static void scanflike(const hte_t *, fcall_t *, int, const char *, type_t **); 64 static void badfmt(const hte_t *, fcall_t *); 65 static void inconarg(const hte_t *, fcall_t *, int); 66 static void tofewarg(const hte_t *, fcall_t *); 67 static void tomanyarg(const hte_t *, fcall_t *); 68 static bool eqtype(type_t *, type_t *, bool, bool, bool, bool *); 69 static bool eqargs(type_t *, type_t *, bool *); 70 static bool mnoarg(type_t *, bool *); 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", false)) != NULL) 82 hte->h_used = true; 83 } 84 85 /* 86 * Performs all tests for a single name 87 */ 88 void 89 chkname(const 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_next) { 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(const 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(const 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_next) { 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(const 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(const 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_next) { 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(const hte_t *hte, sym_t *def, sym_t *decl) 238 { 239 fcall_t *call; 240 char *pos1; 241 type_t *tp1, *tp2; 242 bool 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_next) { 255 tp2 = TP(call->f_type)->t_subt; 256 eq = eqtype(tp1, tp2, 257 true, false, false, (dowarn = false, &dowarn)); 258 if (!call->f_rused) { 259 /* no return value used */ 260 if ((t1 == STRUCT || t1 == UNION) && !eq) { 261 /* 262 * If a function returns a struct or union it 263 * must be declared to return a struct or 264 * union, also if the return value is ignored. 265 * This is necessary because the caller must 266 * allocate stack space for the return value. 267 * If it does not, the return value would over- 268 * write other data. 269 * XXX Following massage may be confusing 270 * because it appears also if the return value 271 * was declared inconsistently. But this 272 * behavior matches pcc based lint, so it is 273 * accepted for now. 274 */ 275 pos1 = xstrdup(mkpos(&def->s_pos)); 276 /* %s function value must be declared ... */ 277 msg(17, hte->h_name, 278 pos1, mkpos(&call->f_pos)); 279 free(pos1); 280 } 281 continue; 282 } 283 if (!eq || (sflag && dowarn)) { 284 pos1 = xstrdup(mkpos(&def->s_pos)); 285 /* %s value used inconsistently \t%s :: %s */ 286 msg(4, hte->h_name, pos1, mkpos(&call->f_pos)); 287 free(pos1); 288 } 289 } 290 } 291 292 /* 293 * Print a warning if a definition/declaration does not match another 294 * definition/declaration of the same name. For functions, only the 295 * types of return values are tested. 296 */ 297 static void 298 chkvtdi(const hte_t *hte, sym_t *def, sym_t *decl) 299 { 300 sym_t *sym; 301 type_t *tp1, *tp2; 302 bool eq, dowarn; 303 char *pos1; 304 305 if (def == NULL) 306 def = decl; 307 if (def == NULL) 308 return; 309 310 tp1 = TP(def->s_type); 311 for (sym = hte->h_syms; sym != NULL; sym = sym->s_next) { 312 type_t *xt1, *xt2; 313 if (sym == def) 314 continue; 315 tp2 = TP(sym->s_type); 316 dowarn = false; 317 if (tp1->t_tspec == FUNC && tp2->t_tspec == FUNC) { 318 eq = eqtype(xt1 = tp1->t_subt, xt2 = tp2->t_subt, 319 true, false, false, &dowarn); 320 } else { 321 eq = eqtype(xt1 = tp1, xt2 = tp2, 322 false, false, false, &dowarn); 323 } 324 if (!eq || (sflag && dowarn)) { 325 pos1 = xstrdup(mkpos(&def->s_pos)); 326 /* %s value declared inconsistently (%s != %s) \t... */ 327 msg(5, hte->h_name, type_name(xt1), type_name(xt2), 328 pos1, 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(const 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_next; 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_next) { 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_check_only_first_args && 386 n >= def->s_check_num_args) 387 break; 388 n++; 389 chkau(hte, n, def, decl, pos1p, call1, call, 390 *ap1, *ap2); 391 ap1++; 392 ap2++; 393 } 394 if (*ap1 == *ap2) { 395 /* equal # of arguments */ 396 } else if (def != NULL && def->s_check_only_first_args && 397 n >= def->s_check_num_args) { 398 /* 399 * function definition with VARARGS; The # of 400 * arguments of the call must be at least as large 401 * as the parameter of VARARGS. 402 */ 403 } else if (*ap2 != NULL && tp1->t_proto && tp1->t_vararg) { 404 /* 405 * prototype with ... and function call with 406 * at least the same # of arguments as declared 407 * in the prototype. 408 */ 409 } else { 410 pos1 = xstrdup(mkpos(pos1p)); 411 /* %s: variable # of args \t%s :: %s */ 412 msg(7, hte->h_name, pos1, mkpos(&call->f_pos)); 413 free(pos1); 414 continue; 415 } 416 417 /* perform SCANFLIKE/PRINTFLIKE tests */ 418 if (def == NULL || (!def->s_printflike && !def->s_scanflike)) 419 continue; 420 as = def->s_printflike 421 ? def->s_printflike_arg 422 : def->s_scanflike_arg; 423 for (ai = call->f_args; ai != NULL; ai = ai->a_next) { 424 if (ai->a_num == as) 425 break; 426 } 427 if (ai == NULL || !ai->a_fmt) 428 continue; 429 if (def->s_printflike) { 430 printflike(hte, call, n, ai->a_fstrg, ap2); 431 } else { 432 scanflike(hte, call, n, ai->a_fstrg, ap2); 433 } 434 } 435 } 436 437 /* 438 * Check a single argument in a function call. 439 * 440 * hte a pointer to the hash table entry of the function 441 * n the number of the argument (1..) 442 * def the function definition or NULL 443 * decl prototype declaration, old style declaration or NULL 444 * pos1p position of definition, declaration of first call 445 * call1 first call, if both def and decl are old style def/decl 446 * call checked call 447 * arg1 currently checked argument of def/decl/call1 448 * arg2 currently checked argument of call 449 * 450 */ 451 static void 452 chkau(const hte_t *hte, int n, sym_t *def, sym_t *decl, pos_t *pos1p, 453 fcall_t *call1, fcall_t *call, type_t *arg1, type_t *arg2) 454 { 455 bool promote, asgn, dowarn; 456 tspec_t t1, t2; 457 arginf_t *ai, *ai1; 458 char *pos1; 459 460 /* 461 * If a function definition is available (def != NULL), we compare the 462 * function call (call) with the definition. Otherwise, if a function 463 * definition is available and it is not an old style definition 464 * (decl != NULL && TP(decl->s_type)->t_proto), we compare the call 465 * with this declaration. Otherwise we compare it with the first 466 * call we have found (call1). 467 */ 468 469 /* arg1 must be promoted if it stems from an old style definition */ 470 promote = def != NULL && def->s_old_style_function; 471 472 /* 473 * If we compare with a definition or declaration, we must perform 474 * the same checks for qualifiers in indirected types as in 475 * assignments. 476 */ 477 asgn = def != NULL || (decl != NULL && TP(decl->s_type)->t_proto); 478 479 dowarn = false; 480 if (eqtype(arg1, arg2, true, promote, asgn, &dowarn) && 481 (!sflag || !dowarn)) 482 return; 483 484 /* 485 * Other lint implementations print warnings as soon as the type 486 * of an argument does not match exactly the expected type. The 487 * result are lots of warnings which are really not necessary. 488 * We print a warning only if 489 * (0) at least one type is not an integer type and types differ 490 * (1) hflag is set and types differ 491 * (2) types differ, except in signedness 492 * If the argument is an integer constant whose msb is not set, 493 * signedness is ignored (e.g. 0 matches both signed and unsigned 494 * int). This is with and without hflag. 495 * If the argument is an integer constant with value 0 and the 496 * expected argument is of type pointer and the width of the 497 * integer constant is the same as the width of the pointer, 498 * no warning is printed. 499 */ 500 t1 = arg1->t_tspec; 501 t2 = arg2->t_tspec; 502 if (is_integer(t1) && is_integer(t2) && 503 !arg1->t_is_enum && !arg2->t_is_enum) { 504 if (promote) { 505 /* 506 * XXX Here is a problem: Although it is possible to 507 * pass an int where a char/short it expected, there 508 * may be loss in significant digits. We should first 509 * check for const arguments if they can be converted 510 * into the original parameter type. 511 */ 512 if (t1 == FLOAT) { 513 t1 = DOUBLE; 514 } else if (t1 == CHAR || t1 == SCHAR) { 515 t1 = INT; 516 } else if (t1 == UCHAR) { 517 t1 = tflag ? UINT : INT; 518 } else if (t1 == SHORT) { 519 t1 = INT; 520 } else if (t1 == USHORT) { 521 /* CONSTCOND */ 522 t1 = INT_MAX < USHRT_MAX || tflag ? UINT : INT; 523 } 524 } 525 526 if (signed_type(t1) == signed_type(t2)) { 527 528 /* 529 * types differ only in signedness; get information 530 * about arguments 531 */ 532 533 /* 534 * treat a definition like a call with variable 535 * arguments 536 */ 537 ai1 = call1 != NULL ? call1->f_args : NULL; 538 539 /* 540 * if two calls are compared, ai1 is set to the 541 * information for the n-th argument, if this was 542 * a constant, otherwise to NULL 543 */ 544 for ( ; ai1 != NULL; ai1 = ai1->a_next) { 545 if (ai1->a_num == n) 546 break; 547 } 548 /* 549 * ai is set to the information of the n-th arg 550 * of the (second) call, if this was a constant, 551 * otherwise to NULL 552 */ 553 for (ai = call->f_args; ai != NULL; ai = ai->a_next) { 554 if (ai->a_num == n) 555 break; 556 } 557 558 if (ai1 == NULL && ai == NULL) { 559 /* no constant at all */ 560 if (!hflag) 561 return; 562 } else if (ai1 == NULL || ai == NULL) { 563 /* one constant */ 564 if (ai == NULL) 565 ai = ai1; 566 if (ai->a_zero || ai->a_pcon) 567 /* same value in signed and unsigned */ 568 return; 569 /* value (not representation) differently */ 570 } else { 571 /* 572 * two constants, one signed, one unsigned; 573 * if the msb of one of the constants is set, 574 * the argument is used inconsistently. 575 */ 576 if (!ai1->a_ncon && !ai->a_ncon) 577 return; 578 } 579 } 580 581 } else if (t1 == PTR && is_integer(t2)) { 582 for (ai = call->f_args; ai != NULL; ai = ai->a_next) { 583 if (ai->a_num == n) 584 break; 585 } 586 /* 587 * Vendor implementations of lint (e.g. HP-UX, Digital UNIX) 588 * don't care about the size of the integer argument, 589 * only whether or not it is zero. We do the same. 590 */ 591 if (ai != NULL && ai->a_zero) 592 return; 593 } 594 595 pos1 = xstrdup(mkpos(pos1p)); 596 /* %s, arg %d used inconsistently \t%s[%s] :: %s[%s] */ 597 msg(6, hte->h_name, n, pos1, type_name(arg1), 598 mkpos(&call->f_pos), type_name(arg2)); 599 free(pos1); 600 } 601 602 /* 603 * Compare the types in the NULL-terminated array ap with the format 604 * string fmt. 605 */ 606 static void 607 printflike(const hte_t *hte, fcall_t *call, int n, const char *fmt, type_t **ap) 608 { 609 const char *fp; 610 int fc; 611 bool fwidth, prec, left, sign, space, alt, zero; 612 tspec_t sz, t1, t2 = NOTSPEC; 613 type_t *tp; 614 615 fp = fmt; 616 fc = *fp++; 617 618 for (;;) { 619 if (fc == '\0') { 620 if (*ap != NULL) 621 tomanyarg(hte, call); 622 break; 623 } 624 if (fc != '%') { 625 badfmt(hte, call); 626 break; 627 } 628 fc = *fp++; 629 fwidth = prec = left = sign = space = alt = zero = false; 630 sz = NOTSPEC; 631 632 /* Flags */ 633 for (;;) { 634 if (fc == '-') { 635 if (left) 636 break; 637 left = true; 638 } else if (fc == '+') { 639 if (sign) 640 break; 641 sign = true; 642 } else if (fc == ' ') { 643 if (space) 644 break; 645 space = true; 646 } else if (fc == '#') { 647 if (alt) 648 break; 649 alt = true; 650 } else if (fc == '0') { 651 if (zero) 652 break; 653 zero = true; 654 } else { 655 break; 656 } 657 fc = *fp++; 658 } 659 660 /* field width */ 661 if (ch_isdigit(fc)) { 662 fwidth = true; 663 do { fc = *fp++; } while (ch_isdigit(fc)); 664 } else if (fc == '*') { 665 fwidth = true; 666 fc = *fp++; 667 if ((tp = *ap++) == NULL) { 668 tofewarg(hte, call); 669 break; 670 } 671 n++; 672 if ((t1 = tp->t_tspec) != INT && (hflag || t1 != UINT)) 673 inconarg(hte, call, n); 674 } 675 676 /* precision */ 677 if (fc == '.') { 678 fc = *fp++; 679 prec = true; 680 if (ch_isdigit(fc)) { 681 do { fc = *fp++; } while (ch_isdigit(fc)); 682 } else if (fc == '*') { 683 fc = *fp++; 684 if ((tp = *ap++) == NULL) { 685 tofewarg(hte, call); 686 break; 687 } 688 n++; 689 if (tp->t_tspec != INT) 690 inconarg(hte, call, n); 691 } else { 692 badfmt(hte, call); 693 break; 694 } 695 } 696 697 if (fc == 'h') { 698 sz = SHORT; 699 } else if (fc == 'l') { 700 sz = LONG; 701 } else if (fc == 'q') { 702 sz = QUAD; 703 } else if (fc == 'L') { 704 sz = LDOUBLE; 705 } 706 if (sz != NOTSPEC) 707 fc = *fp++; 708 709 if (fc == '%') { 710 if (sz != NOTSPEC || left || sign || space || 711 alt || zero || prec || fwidth) { 712 badfmt(hte, call); 713 } 714 fc = *fp++; 715 continue; 716 } 717 718 if (fc == '\0') { 719 badfmt(hte, call); 720 break; 721 } 722 723 if ((tp = *ap++) == NULL) { 724 tofewarg(hte, call); 725 break; 726 } 727 n++; 728 if ((t1 = tp->t_tspec) == PTR) 729 t2 = tp->t_subt->t_tspec; 730 731 if (fc == 'd' || fc == 'i') { 732 if (alt || sz == LDOUBLE) { 733 badfmt(hte, call); 734 break; 735 } 736 int_conv: 737 if (sz == LONG) { 738 if (t1 != LONG && (hflag || t1 != ULONG)) 739 inconarg(hte, call, n); 740 } else if (sz == QUAD) { 741 if (t1 != QUAD && (hflag || t1 != UQUAD)) 742 inconarg(hte, call, n); 743 } else { 744 /* 745 * SHORT is always promoted to INT, USHORT 746 * to INT or UINT. 747 */ 748 if (t1 != INT && (hflag || t1 != UINT)) 749 inconarg(hte, call, n); 750 } 751 } else if (fc == 'o' || fc == 'u' || fc == 'x' || fc == 'X') { 752 if ((alt && fc == 'u') || sz == LDOUBLE) 753 badfmt(hte, call); 754 uint_conv: 755 if (sz == LONG) { 756 if (t1 != ULONG && (hflag || t1 != LONG)) 757 inconarg(hte, call, n); 758 } else if (sz == QUAD) { 759 if (t1 != UQUAD && (hflag || t1 != QUAD)) 760 inconarg(hte, call, n); 761 } else if (sz == SHORT) { 762 /* USHORT was promoted to INT or UINT */ 763 if (t1 != UINT && t1 != INT) 764 inconarg(hte, call, n); 765 } else { 766 if (t1 != UINT && (hflag || t1 != INT)) 767 inconarg(hte, call, n); 768 } 769 } else if (fc == 'D' || fc == 'O' || fc == 'U') { 770 if ((alt && fc != 'O') || sz != NOTSPEC || !tflag) 771 badfmt(hte, call); 772 sz = LONG; 773 if (fc == 'D') { 774 goto int_conv; 775 } else { 776 goto uint_conv; 777 } 778 } else if (fc == 'f' || fc == 'e' || fc == 'E' || 779 fc == 'g' || fc == 'G') { 780 if (sz == NOTSPEC) 781 sz = DOUBLE; 782 if (sz != DOUBLE && sz != LDOUBLE) 783 badfmt(hte, call); 784 if (t1 != sz) 785 inconarg(hte, call, n); 786 } else if (fc == 'c') { 787 if (sz != NOTSPEC || alt || zero) 788 badfmt(hte, call); 789 if (t1 != INT) 790 inconarg(hte, call, n); 791 } else if (fc == 's') { 792 if (sz != NOTSPEC || alt || zero) 793 badfmt(hte, call); 794 if (t1 != PTR || 795 (t2 != CHAR && t2 != UCHAR && t2 != SCHAR)) { 796 inconarg(hte, call, n); 797 } 798 } else if (fc == 'p') { 799 if (fwidth || prec || sz != NOTSPEC || alt || zero) 800 badfmt(hte, call); 801 if (t1 != PTR || (hflag && t2 != VOID)) 802 inconarg(hte, call, n); 803 } else if (fc == 'n') { 804 if (fwidth || prec || alt || zero || sz == LDOUBLE) 805 badfmt(hte, call); 806 if (t1 != PTR) { 807 inconarg(hte, call, n); 808 } else if (sz == LONG) { 809 if (t2 != LONG && t2 != ULONG) 810 inconarg(hte, call, n); 811 } else if (sz == SHORT) { 812 if (t2 != SHORT && t2 != USHORT) 813 inconarg(hte, call, n); 814 } else { 815 if (t2 != INT && t2 != UINT) 816 inconarg(hte, call, n); 817 } 818 } else { 819 badfmt(hte, call); 820 break; 821 } 822 823 fc = *fp++; 824 } 825 } 826 827 /* 828 * Compare the types in the NULL-terminated array ap with the format 829 * string fmt. 830 */ 831 static void 832 scanflike(const hte_t *hte, fcall_t *call, int n, const char *fmt, type_t **ap) 833 { 834 const char *fp; 835 int fc; 836 bool noasgn, fwidth; 837 tspec_t sz, t1 = NOTSPEC, t2 = NOTSPEC; 838 type_t *tp = NULL; 839 840 fp = fmt; 841 fc = *fp++; 842 843 for (;;) { 844 if (fc == '\0') { 845 if (*ap != NULL) 846 tomanyarg(hte, call); 847 break; 848 } 849 if (fc != '%') { 850 badfmt(hte, call); 851 break; 852 } 853 fc = *fp++; 854 855 noasgn = fwidth = false; 856 sz = NOTSPEC; 857 858 if (fc == '*') { 859 noasgn = true; 860 fc = *fp++; 861 } 862 863 if (ch_isdigit(fc)) { 864 fwidth = true; 865 do { fc = *fp++; } while (ch_isdigit(fc)); 866 } 867 868 if (fc == 'h') { 869 sz = SHORT; 870 } else if (fc == 'l') { 871 sz = LONG; 872 } else if (fc == 'q') { 873 sz = QUAD; 874 } else if (fc == 'L') { 875 sz = LDOUBLE; 876 } 877 if (sz != NOTSPEC) 878 fc = *fp++; 879 880 if (fc == '%') { 881 if (sz != NOTSPEC || noasgn || fwidth) 882 badfmt(hte, call); 883 fc = *fp++; 884 continue; 885 } 886 887 if (!noasgn) { 888 if ((tp = *ap++) == NULL) { 889 tofewarg(hte, call); 890 break; 891 } 892 n++; 893 if ((t1 = tp->t_tspec) == PTR) 894 t2 = tp->t_subt->t_tspec; 895 } 896 897 if (fc == 'd' || fc == 'i' || fc == 'n') { 898 if (sz == LDOUBLE) 899 badfmt(hte, call); 900 if (sz != SHORT && sz != LONG && sz != QUAD) 901 sz = INT; 902 conv: 903 if (!noasgn) { 904 if (t1 != PTR) { 905 inconarg(hte, call, n); 906 } else if (t2 != signed_type(sz)) { 907 inconarg(hte, call, n); 908 } else if (hflag && t2 != sz) { 909 inconarg(hte, call, n); 910 } else if (tp->t_subt->t_const) { 911 inconarg(hte, call, n); 912 } 913 } 914 } else if (fc == 'o' || fc == 'u' || fc == 'x') { 915 if (sz == LDOUBLE) 916 badfmt(hte, call); 917 if (sz == SHORT) { 918 sz = USHORT; 919 } else if (sz == LONG) { 920 sz = ULONG; 921 } else if (sz == QUAD) { 922 sz = UQUAD; 923 } else { 924 sz = UINT; 925 } 926 goto conv; 927 } else if (fc == 'D') { 928 if (sz != NOTSPEC || !tflag) 929 badfmt(hte, call); 930 sz = LONG; 931 goto conv; 932 } else if (fc == 'O') { 933 if (sz != NOTSPEC || !tflag) 934 badfmt(hte, call); 935 sz = ULONG; 936 goto conv; 937 } else if (fc == 'X') { 938 /* 939 * XXX valid in ANSI C, but in NetBSD's libc imple- 940 * mented as "lx". That's why it should be avoided. 941 */ 942 if (sz != NOTSPEC || !tflag) 943 badfmt(hte, call); 944 sz = ULONG; 945 goto conv; 946 } else if (fc == 'E') { 947 /* 948 * XXX valid in ANSI C, but in NetBSD's libc imple- 949 * mented as "lf". That's why it should be avoided. 950 */ 951 if (sz != NOTSPEC || !tflag) 952 badfmt(hte, call); 953 sz = DOUBLE; 954 goto conv; 955 } else if (fc == 'F') { 956 /* XXX only for backward compatibility */ 957 if (sz != NOTSPEC || !tflag) 958 badfmt(hte, call); 959 sz = DOUBLE; 960 goto conv; 961 } else if (fc == 'G') { 962 /* 963 * XXX valid in ANSI C, but in NetBSD's libc not 964 * implemented 965 */ 966 if (sz != NOTSPEC && sz != LONG && sz != LDOUBLE) 967 badfmt(hte, call); 968 goto fconv; 969 } else if (fc == 'e' || fc == 'f' || fc == 'g') { 970 fconv: 971 if (sz == NOTSPEC) { 972 sz = FLOAT; 973 } else if (sz == LONG) { 974 sz = DOUBLE; 975 } else if (sz != LDOUBLE) { 976 badfmt(hte, call); 977 sz = FLOAT; 978 } 979 goto conv; 980 } else if (fc == 's' || fc == '[' || fc == 'c') { 981 if (sz != NOTSPEC) 982 badfmt(hte, call); 983 if (fc == '[') { 984 if ((fc = *fp++) == '-') { 985 badfmt(hte, call); 986 fc = *fp++; 987 } 988 if (fc != ']') { 989 badfmt(hte, call); 990 if (fc == '\0') 991 break; 992 } 993 } 994 if (!noasgn) { 995 if (t1 != PTR) { 996 inconarg(hte, call, n); 997 } else if (t2 != CHAR && t2 != UCHAR && 998 t2 != SCHAR) { 999 inconarg(hte, call, n); 1000 } 1001 } 1002 } else if (fc == 'p') { 1003 if (sz != NOTSPEC) 1004 badfmt(hte, call); 1005 if (!noasgn) { 1006 if (t1 != PTR || t2 != PTR) { 1007 inconarg(hte, call, n); 1008 } else if (tp->t_subt->t_subt->t_tspec!=VOID) { 1009 if (hflag) 1010 inconarg(hte, call, n); 1011 } 1012 } 1013 } else { 1014 badfmt(hte, call); 1015 break; 1016 } 1017 1018 fc = *fp++; 1019 } 1020 } 1021 1022 static void 1023 badfmt(const hte_t *hte, fcall_t *call) 1024 { 1025 1026 /* %s: malformed format string \t%s */ 1027 msg(13, hte->h_name, mkpos(&call->f_pos)); 1028 } 1029 1030 static void 1031 inconarg(const hte_t *hte, fcall_t *call, int n) 1032 { 1033 1034 /* %s, arg %d inconsistent with format \t%s */ 1035 msg(14, hte->h_name, n, mkpos(&call->f_pos)); 1036 } 1037 1038 static void 1039 tofewarg(const hte_t *hte, fcall_t *call) 1040 { 1041 1042 /* %s: too few args for format \t%s */ 1043 msg(15, hte->h_name, mkpos(&call->f_pos)); 1044 } 1045 1046 static void 1047 tomanyarg(const hte_t *hte, fcall_t *call) 1048 { 1049 1050 /* %s: too many args for format \t%s */ 1051 msg(16, hte->h_name, mkpos(&call->f_pos)); 1052 } 1053 1054 /* 1055 * List of functions where we usually don't care about their result. 1056 * NB: Must be sorted. 1057 */ 1058 static const char ignorelist[][8] = { 1059 "memcpy", 1060 "memmove", 1061 "memset", 1062 "printf", 1063 "strcat", 1064 "strcpy", 1065 "vprintf", 1066 }; 1067 1068 /* 1069 * Print warnings for return values which are used, but not returned, 1070 * or return values which are always or sometimes ignored. 1071 */ 1072 static void 1073 chkrvu(const hte_t *hte, sym_t *def) 1074 { 1075 fcall_t *call; 1076 bool used, ignored; 1077 1078 if (def == NULL) 1079 /* don't know whether or not the functions returns a value */ 1080 return; 1081 1082 if (hte->h_calls == NULL) 1083 return; 1084 1085 if (def->s_function_has_return_value) { 1086 /* 1087 * XXX as soon as we are able to disable single warnings 1088 * the following dependencies from hflag should be removed. 1089 * but for now I don't want to be bothered by this warnings 1090 * which are almost always useless. 1091 */ 1092 if (!hflag) 1093 return; 1094 if (hflag && bsearch(hte->h_name, ignorelist, 1095 __arraycount(ignorelist), sizeof(ignorelist[0]), 1096 (int (*)(const void *, const void *))strcmp) != NULL) 1097 return; 1098 1099 /* function has return value */ 1100 used = ignored = false; 1101 for (call = hte->h_calls; call != NULL; call = call->f_next) { 1102 used |= call->f_rused || call->f_rdisc; 1103 ignored |= !call->f_rused && !call->f_rdisc; 1104 } 1105 if (!used && ignored) { 1106 /* %s returns value which is always ignored */ 1107 msg(8, hte->h_name); 1108 } else if (used && ignored) { 1109 /* %s returns value which is sometimes ignored */ 1110 msg(9, hte->h_name); 1111 } 1112 } else { 1113 /* function has no return value */ 1114 for (call = hte->h_calls; call != NULL; call = call->f_next) { 1115 if (call->f_rused) 1116 /* %s value is used( %s ), but none returned */ 1117 msg(10, hte->h_name, mkpos(&call->f_pos)); 1118 } 1119 } 1120 } 1121 1122 /* 1123 * Print warnings for inconsistent argument declarations. 1124 */ 1125 static void 1126 chkadecl(const hte_t *hte, sym_t *def, sym_t *decl) 1127 { 1128 bool osdef, eq, dowarn; 1129 int n; 1130 sym_t *sym1, *sym; 1131 type_t **ap1, **ap2, *tp1, *tp2; 1132 char *pos1; 1133 const char *pos2; 1134 1135 osdef = false; 1136 if (def != NULL) { 1137 osdef = def->s_old_style_function; 1138 sym1 = def; 1139 } else if (decl != NULL && TP(decl->s_type)->t_proto) { 1140 sym1 = decl; 1141 } else { 1142 return; 1143 } 1144 if (TP(sym1->s_type)->t_tspec != FUNC) 1145 return; 1146 1147 /* 1148 * XXX Prototypes should also be compared with old style function 1149 * declarations. 1150 */ 1151 1152 for (sym = hte->h_syms; sym != NULL; sym = sym->s_next) { 1153 if (sym == sym1 || !TP(sym->s_type)->t_proto) 1154 continue; 1155 ap1 = TP(sym1->s_type)->t_args; 1156 ap2 = TP(sym->s_type)->t_args; 1157 n = 0; 1158 while (*ap1 != NULL && *ap2 != NULL) { 1159 type_t *xt1, *xt2; 1160 dowarn = false; 1161 eq = eqtype(xt1 = *ap1, xt2 = *ap2, 1162 true, osdef, false, &dowarn); 1163 if (!eq || dowarn) { 1164 pos1 = xstrdup(mkpos(&sym1->s_pos)); 1165 pos2 = mkpos(&sym->s_pos); 1166 /* %s, arg %d declared inconsistently ... */ 1167 msg(11, hte->h_name, n + 1, 1168 type_name(xt1), type_name(xt2), pos1, pos2); 1169 free(pos1); 1170 } 1171 n++; 1172 ap1++; 1173 ap2++; 1174 } 1175 if (*ap1 == *ap2) { 1176 tp1 = TP(sym1->s_type); 1177 tp2 = TP(sym->s_type); 1178 if (tp1->t_vararg == tp2->t_vararg) 1179 continue; 1180 if (tp2->t_vararg && sym1->s_check_only_first_args && 1181 sym1->s_check_num_args == n && !sflag) { 1182 continue; 1183 } 1184 } 1185 pos1 = xstrdup(mkpos(&sym1->s_pos)); 1186 /* %s: variable # of args declared \t%s :: %s */ 1187 msg(12, hte->h_name, pos1, mkpos(&sym->s_pos)); 1188 free(pos1); 1189 } 1190 } 1191 1192 1193 /* 1194 * Check compatibility of two types. Returns whether types are compatible. 1195 * 1196 * ignqual if set, ignore qualifiers of outermost type; used for 1197 * function arguments 1198 * promote if set, promote left type before comparison; used for 1199 * comparisons of arguments with parameters of old style 1200 * definitions 1201 * asgn left indirected type must have at least the same qualifiers 1202 * like right indirected type (for assignments and function 1203 * arguments) 1204 * *dowarn set to true if an old style declaration was compared with 1205 * an incompatible prototype declaration 1206 */ 1207 static bool 1208 eqtype(type_t *tp1, type_t *tp2, bool ignqual, bool promot, bool asgn, 1209 bool *dowarn) 1210 { 1211 tspec_t t, to; 1212 int indir; 1213 1214 to = NOTSPEC; 1215 indir = 0; 1216 1217 while (tp1 != NULL && tp2 != NULL) { 1218 1219 t = tp1->t_tspec; 1220 if (promot) { 1221 if (t == FLOAT) { 1222 t = DOUBLE; 1223 } else if (t == CHAR || t == SCHAR) { 1224 t = INT; 1225 } else if (t == UCHAR) { 1226 t = tflag ? UINT : INT; 1227 } else if (t == SHORT) { 1228 t = INT; 1229 } else if (t == USHORT) { 1230 /* CONSTCOND */ 1231 t = INT_MAX < USHRT_MAX || tflag ? UINT : INT; 1232 } 1233 } 1234 1235 if (asgn && to == PTR) { 1236 if (indir == 1 && (t == VOID || tp2->t_tspec == VOID)) 1237 return true; 1238 } 1239 1240 if (t != tp2->t_tspec) { 1241 /* 1242 * Give pointer to types which differ only in 1243 * signedness a chance if not sflag and not hflag. 1244 */ 1245 if (sflag || hflag || to != PTR) 1246 return false; 1247 if (signed_type(t) != signed_type(tp2->t_tspec)) 1248 return false; 1249 } 1250 1251 if (tp1->t_is_enum && tp2->t_is_enum) { 1252 if (tp1->t_istag && tp2->t_istag) { 1253 return tp1->t_tag == tp2->t_tag; 1254 } else if (tp1->t_istynam && tp2->t_istynam) { 1255 return tp1->t_tynam == tp2->t_tynam; 1256 } else if (tp1->t_isuniqpos && tp2->t_isuniqpos) { 1257 return (tp1->t_uniqpos.p_line == 1258 tp2->t_uniqpos.p_line && 1259 tp1->t_uniqpos.p_file == 1260 tp2->t_uniqpos.p_file && 1261 tp1->t_uniqpos.p_uniq == 1262 tp2->t_uniqpos.p_uniq); 1263 } else { 1264 return false; 1265 } 1266 } 1267 1268 /* 1269 * XXX Handle combinations of enum and int if eflag is set. 1270 * But note: enum and 0 should be allowed. 1271 */ 1272 1273 if (asgn && indir == 1) { 1274 if (!tp1->t_const && tp2->t_const) 1275 return false; 1276 if (!tp1->t_volatile && tp2->t_volatile) 1277 return false; 1278 } else if (!ignqual && !tflag) { 1279 if (tp1->t_const != tp2->t_const) 1280 return false; 1281 if (tp1->t_const != tp2->t_const) 1282 return false; 1283 } 1284 1285 if (t == STRUCT || t == UNION) { 1286 if (tp1->t_istag && tp2->t_istag) { 1287 return tp1->t_tag == tp2->t_tag; 1288 } else if (tp1->t_istynam && tp2->t_istynam) { 1289 return tp1->t_tynam == tp2->t_tynam; 1290 } else if (tp1->t_isuniqpos && tp2->t_isuniqpos) { 1291 return (tp1->t_uniqpos.p_line == 1292 tp2->t_uniqpos.p_line && 1293 tp1->t_uniqpos.p_file == 1294 tp2->t_uniqpos.p_file && 1295 tp1->t_uniqpos.p_uniq == 1296 tp2->t_uniqpos.p_uniq); 1297 } else { 1298 return false; 1299 } 1300 } 1301 1302 if (t == ARRAY && tp1->t_dim != tp2->t_dim) { 1303 if (tp1->t_dim != 0 && tp2->t_dim != 0) 1304 return false; 1305 } 1306 1307 if (t == FUNC) { 1308 if (tp1->t_proto && tp2->t_proto) { 1309 if (!eqargs(tp1, tp2, dowarn)) 1310 return false; 1311 } else if (tp1->t_proto) { 1312 if (!mnoarg(tp1, dowarn)) 1313 return false; 1314 } else if (tp2->t_proto) { 1315 if (!mnoarg(tp2, dowarn)) 1316 return false; 1317 } 1318 } 1319 1320 tp1 = tp1->t_subt; 1321 tp2 = tp2->t_subt; 1322 ignqual = promot = false; 1323 to = t; 1324 indir++; 1325 1326 } 1327 1328 return tp1 == tp2; 1329 } 1330 1331 /* 1332 * Compares arguments of two prototypes 1333 */ 1334 static bool 1335 eqargs(type_t *tp1, type_t *tp2, bool *dowarn) 1336 { 1337 type_t **a1, **a2; 1338 1339 if (tp1->t_vararg != tp2->t_vararg) 1340 return false; 1341 1342 a1 = tp1->t_args; 1343 a2 = tp2->t_args; 1344 1345 while (*a1 != NULL && *a2 != NULL) { 1346 1347 if (!eqtype(*a1, *a2, true, false, false, dowarn)) 1348 return false; 1349 1350 a1++; 1351 a2++; 1352 1353 } 1354 1355 return *a1 == *a2; 1356 } 1357 1358 /* 1359 * mnoarg() (matches functions with no argument type information) 1360 * returns true if all parameters of a prototype are compatible with 1361 * and old style function declaration. 1362 * This is the case if following conditions are met: 1363 * 1. the prototype must have a fixed number of parameters 1364 * 2. no parameter is of type float 1365 * 3. no parameter is converted to another type if integer promotion 1366 * is applied on it 1367 */ 1368 static bool 1369 mnoarg(type_t *tp, bool *dowarn) 1370 { 1371 type_t **arg; 1372 tspec_t t; 1373 1374 if (tp->t_vararg && dowarn != NULL) 1375 *dowarn = true; 1376 for (arg = tp->t_args; *arg != NULL; arg++) { 1377 if ((t = (*arg)->t_tspec) == FLOAT) 1378 return false; 1379 if (t == CHAR || t == SCHAR || t == UCHAR) 1380 return false; 1381 if (t == SHORT || t == USHORT) 1382 return false; 1383 } 1384 return true; 1385 } 1386
Indexes created Tue Oct 14 21:09:58 GMT 2025