chk.c revision 1.51
1 /* $NetBSD: chk.c,v 1.51 2022/08/28 12:04:47 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) 41 __RCSID("$NetBSD: chk.c,v 1.51 2022/08/28 12:04:47 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 types_compatible(type_t *, type_t *, bool, bool, bool, bool *); 69 static bool prototypes_compatible(type_t *, type_t *, bool *); 70 static bool matches_no_arg_function(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 = types_compatible(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 268 * overwrite other data. 269 * 270 * XXX Following message may be confusing 271 * because it appears also if the return value 272 * was declared inconsistently. But this 273 * behavior matches pcc-based lint, so it is 274 * accepted for now. 275 */ 276 pos1 = xstrdup(mkpos(&def->s_pos)); 277 /* %s function value must be declared ... */ 278 msg(17, hte->h_name, 279 pos1, mkpos(&call->f_pos)); 280 free(pos1); 281 } 282 continue; 283 } 284 if (!eq || (sflag && dowarn)) { 285 pos1 = xstrdup(mkpos(&def->s_pos)); 286 /* %s value used inconsistently \t%s :: %s */ 287 msg(4, hte->h_name, pos1, mkpos(&call->f_pos)); 288 free(pos1); 289 } 290 } 291 } 292 293 /* 294 * Print a warning if a definition/declaration does not match another 295 * definition/declaration of the same name. For functions, only the 296 * types of return values are tested. 297 */ 298 static void 299 chkvtdi(const hte_t *hte, sym_t *def, sym_t *decl) 300 { 301 sym_t *sym; 302 type_t *tp1, *tp2; 303 bool eq, dowarn; 304 char *pos1; 305 306 if (def == NULL) 307 def = decl; 308 if (def == NULL) 309 return; 310 311 tp1 = TP(def->s_type); 312 for (sym = hte->h_syms; sym != NULL; sym = sym->s_next) { 313 type_t *xt1, *xt2; 314 if (sym == def) 315 continue; 316 tp2 = TP(sym->s_type); 317 dowarn = false; 318 if (tp1->t_tspec == FUNC && tp2->t_tspec == FUNC) { 319 eq = types_compatible(xt1 = tp1->t_subt, 320 xt2 = tp2->t_subt, true, false, false, &dowarn); 321 } else { 322 eq = types_compatible(xt1 = tp1, xt2 = tp2, 323 false, false, false, &dowarn); 324 } 325 if (!eq || (sflag && dowarn)) { 326 pos1 = xstrdup(mkpos(&def->s_pos)); 327 /* %s value declared inconsistently (%s != %s) \t... */ 328 msg(5, hte->h_name, type_name(xt1), type_name(xt2), 329 pos1, mkpos(&sym->s_pos)); 330 free(pos1); 331 } 332 } 333 } 334 335 /* 336 * Print a warning if a function is called with arguments which does 337 * not match the function definition, declaration or another call 338 * of the same function. 339 */ 340 static void 341 chkfaui(const hte_t *hte, sym_t *def, sym_t *decl) 342 { 343 type_t *tp1, *tp2, **ap1, **ap2; 344 pos_t *pos1p = NULL; 345 fcall_t *calls, *call, *call1; 346 int n, as; 347 char *pos1; 348 arginf_t *ai; 349 350 if ((calls = hte->h_calls) == NULL) 351 return; 352 353 /* 354 * If we find a function definition, we use this for comparison, 355 * otherwise the first prototype we can find. If there is no 356 * definition or prototype declaration, the first function call 357 * is used. 358 */ 359 tp1 = NULL; 360 call1 = NULL; 361 if (def != NULL) { 362 if ((tp1 = TP(def->s_type))->t_tspec != FUNC) 363 return; 364 pos1p = &def->s_pos; 365 } else if (decl != NULL && TP(decl->s_type)->t_proto) { 366 if ((tp1 = TP(decl->s_type))->t_tspec != FUNC) 367 return; 368 pos1p = &decl->s_pos; 369 } 370 if (tp1 == NULL) { 371 call1 = calls; 372 calls = calls->f_next; 373 if ((tp1 = TP(call1->f_type))->t_tspec != FUNC) 374 return; 375 pos1p = &call1->f_pos; 376 } 377 378 n = 1; 379 for (call = calls; call != NULL; call = call->f_next) { 380 if ((tp2 = TP(call->f_type))->t_tspec != FUNC) 381 continue; 382 ap1 = tp1->t_args; 383 ap2 = tp2->t_args; 384 n = 0; 385 while (*ap1 != NULL && *ap2 != NULL) { 386 if (def != NULL && def->s_check_only_first_args && 387 n >= def->s_check_num_args) 388 break; 389 n++; 390 chkau(hte, n, def, decl, pos1p, call1, call, 391 *ap1, *ap2); 392 ap1++; 393 ap2++; 394 } 395 if (*ap1 == *ap2) { 396 /* equal # of arguments */ 397 } else if (def != NULL && def->s_check_only_first_args && 398 n >= def->s_check_num_args) { 399 /* 400 * function definition with VARARGS; The # of 401 * arguments of the call must be at least as large 402 * as the parameter of VARARGS. 403 */ 404 } else if (*ap2 != NULL && tp1->t_proto && tp1->t_vararg) { 405 /* 406 * prototype with ... and function call with 407 * at least the same # of arguments as declared 408 * in the prototype. 409 */ 410 } else { 411 pos1 = xstrdup(mkpos(pos1p)); 412 /* %s: variable # of args \t%s :: %s */ 413 msg(7, hte->h_name, pos1, mkpos(&call->f_pos)); 414 free(pos1); 415 continue; 416 } 417 418 /* perform SCANFLIKE/PRINTFLIKE tests */ 419 if (def == NULL || (!def->s_printflike && !def->s_scanflike)) 420 continue; 421 as = def->s_printflike 422 ? def->s_printflike_arg 423 : def->s_scanflike_arg; 424 for (ai = call->f_args; ai != NULL; ai = ai->a_next) { 425 if (ai->a_num == as) 426 break; 427 } 428 if (ai == NULL || !ai->a_fmt) 429 continue; 430 if (def->s_printflike) { 431 printflike(hte, call, n, ai->a_fstrg, ap2); 432 } else { 433 scanflike(hte, call, n, ai->a_fstrg, ap2); 434 } 435 } 436 } 437 438 /* 439 * Check a single argument in a function call. 440 * 441 * hte a pointer to the hash table entry of the function 442 * n the number of the argument (1..) 443 * def the function definition or NULL 444 * decl prototype declaration, old style declaration or NULL 445 * pos1p position of definition, declaration of first call 446 * call1 first call, if both def and decl are old style def/decl 447 * call checked call 448 * arg1 currently checked argument of def/decl/call1 449 * arg2 currently checked argument of call 450 * 451 */ 452 static void 453 chkau(const hte_t *hte, int n, sym_t *def, sym_t *decl, pos_t *pos1p, 454 fcall_t *call1, fcall_t *call, type_t *arg1, type_t *arg2) 455 { 456 bool promote, asgn, dowarn; 457 tspec_t t1, t2; 458 arginf_t *ai, *ai1; 459 char *pos1; 460 461 /* 462 * If a function definition is available (def != NULL), we compare the 463 * function call (call) with the definition. Otherwise, if a function 464 * definition is available and it is not an old style definition 465 * (decl != NULL && TP(decl->s_type)->t_proto), we compare the call 466 * with this declaration. Otherwise we compare it with the first 467 * call we have found (call1). 468 */ 469 470 /* arg1 must be promoted if it stems from an old style definition */ 471 promote = def != NULL && def->s_old_style_function; 472 473 /* 474 * If we compare with a definition or declaration, we must perform 475 * the same checks for qualifiers in indirected types as in 476 * assignments. 477 */ 478 asgn = def != NULL || (decl != NULL && TP(decl->s_type)->t_proto); 479 480 dowarn = false; 481 if (types_compatible(arg1, arg2, true, promote, asgn, &dowarn) && 482 (!sflag || !dowarn)) 483 return; 484 485 /* 486 * Other lint implementations print warnings as soon as the type 487 * of an argument does not match exactly the expected type. The 488 * result are lots of warnings which are really not necessary. 489 * We print a warning only if 490 * (0) at least one type is not an integer type and types differ 491 * (1) hflag is set and types differ 492 * (2) types differ, except in signedness 493 * If the argument is an integer constant whose msb is not set, 494 * signedness is ignored (e.g. 0 matches both signed and unsigned 495 * int). This is with and without hflag. 496 * If the argument is an integer constant with value 0 and the 497 * expected argument is of type pointer and the width of the 498 * integer constant is the same as the width of the pointer, 499 * no warning is printed. 500 */ 501 t1 = arg1->t_tspec; 502 t2 = arg2->t_tspec; 503 if (is_integer(t1) && is_integer(t2) && 504 !arg1->t_is_enum && !arg2->t_is_enum) { 505 if (promote) { 506 /* 507 * XXX Here is a problem: Although it is possible to 508 * pass an int where a char/short it expected, there 509 * may be loss in significant digits. We should first 510 * check for const arguments if they can be converted 511 * into the original parameter type. 512 */ 513 if (t1 == FLOAT) { 514 t1 = DOUBLE; 515 } else if (t1 == CHAR || t1 == SCHAR) { 516 t1 = INT; 517 } else if (t1 == UCHAR) { 518 t1 = tflag ? UINT : INT; 519 } else if (t1 == SHORT) { 520 t1 = INT; 521 } else if (t1 == USHORT) { 522 /* CONSTCOND */ 523 t1 = INT_MAX < USHRT_MAX || tflag ? UINT : INT; 524 } 525 } 526 527 if (signed_type(t1) == signed_type(t2)) { 528 529 /* 530 * types differ only in signedness; get information 531 * about arguments 532 */ 533 534 /* 535 * treat a definition like a call with variable 536 * arguments 537 */ 538 ai1 = call1 != NULL ? call1->f_args : NULL; 539 540 /* 541 * if two calls are compared, ai1 is set to the 542 * information for the n-th argument, if this was 543 * a constant, otherwise to NULL 544 */ 545 for ( ; ai1 != NULL; ai1 = ai1->a_next) { 546 if (ai1->a_num == n) 547 break; 548 } 549 /* 550 * ai is set to the information of the n-th arg 551 * of the (second) call, if this was a constant, 552 * otherwise to NULL 553 */ 554 for (ai = call->f_args; ai != NULL; ai = ai->a_next) { 555 if (ai->a_num == n) 556 break; 557 } 558 559 if (ai1 == NULL && ai == NULL) { 560 /* no constant at all */ 561 if (!hflag) 562 return; 563 } else if (ai1 == NULL || ai == NULL) { 564 /* one constant */ 565 if (ai == NULL) 566 ai = ai1; 567 if (ai->a_zero || ai->a_pcon) 568 /* same value in signed and unsigned */ 569 return; 570 /* value (not representation) differently */ 571 } else { 572 /* 573 * two constants, one signed, one unsigned; 574 * if the msb of one of the constants is set, 575 * the argument is used inconsistently. 576 */ 577 if (!ai1->a_ncon && !ai->a_ncon) 578 return; 579 } 580 } 581 582 } else if (t1 == PTR && is_integer(t2)) { 583 for (ai = call->f_args; ai != NULL; ai = ai->a_next) { 584 if (ai->a_num == n) 585 break; 586 } 587 /* 588 * Vendor implementations of lint (e.g. HP-UX, Digital UNIX) 589 * don't care about the size of the integer argument, 590 * only whether or not it is zero. We do the same. 591 */ 592 if (ai != NULL && ai->a_zero) 593 return; 594 } 595 596 pos1 = xstrdup(mkpos(pos1p)); 597 /* %s, arg %d used inconsistently \t%s[%s] :: %s[%s] */ 598 msg(6, hte->h_name, n, pos1, type_name(arg1), 599 mkpos(&call->f_pos), type_name(arg2)); 600 free(pos1); 601 } 602 603 /* 604 * Compare the types in the NULL-terminated array ap with the format 605 * string fmt. 606 */ 607 static void 608 printflike(const hte_t *hte, fcall_t *call, int n, const char *fmt, type_t **ap) 609 { 610 const char *fp; 611 char fc; 612 bool fwidth, prec, left, sign, space, alt, zero; 613 tspec_t sz, t1, t2 = NOTSPEC; 614 type_t *tp; 615 616 fp = fmt; 617 fc = *fp++; 618 619 for (;;) { 620 if (fc == '\0') { 621 if (*ap != NULL) 622 tomanyarg(hte, call); 623 break; 624 } 625 if (fc != '%') { 626 badfmt(hte, call); 627 break; 628 } 629 fc = *fp++; 630 fwidth = prec = left = sign = space = alt = zero = false; 631 sz = NOTSPEC; 632 633 /* Flags */ 634 for (;;) { 635 if (fc == '-') { 636 if (left) 637 break; 638 left = true; 639 } else if (fc == '+') { 640 if (sign) 641 break; 642 sign = true; 643 } else if (fc == ' ') { 644 if (space) 645 break; 646 space = true; 647 } else if (fc == '#') { 648 if (alt) 649 break; 650 alt = true; 651 } else if (fc == '0') { 652 if (zero) 653 break; 654 zero = true; 655 } else { 656 break; 657 } 658 fc = *fp++; 659 } 660 661 /* field width */ 662 if (ch_isdigit(fc)) { 663 fwidth = true; 664 do { fc = *fp++; } while (ch_isdigit(fc)); 665 } else if (fc == '*') { 666 fwidth = true; 667 fc = *fp++; 668 if ((tp = *ap++) == NULL) { 669 tofewarg(hte, call); 670 break; 671 } 672 n++; 673 if ((t1 = tp->t_tspec) != INT && (hflag || t1 != UINT)) 674 inconarg(hte, call, n); 675 } 676 677 /* precision */ 678 if (fc == '.') { 679 fc = *fp++; 680 prec = true; 681 if (ch_isdigit(fc)) { 682 do { fc = *fp++; } while (ch_isdigit(fc)); 683 } else if (fc == '*') { 684 fc = *fp++; 685 if ((tp = *ap++) == NULL) { 686 tofewarg(hte, call); 687 break; 688 } 689 n++; 690 if (tp->t_tspec != INT) 691 inconarg(hte, call, n); 692 } else { 693 badfmt(hte, call); 694 break; 695 } 696 } 697 698 if (fc == 'h') { 699 sz = SHORT; 700 } else if (fc == 'l') { 701 sz = LONG; 702 } else if (fc == 'q') { 703 sz = QUAD; 704 } else if (fc == 'L') { 705 sz = LDOUBLE; 706 } 707 if (sz != NOTSPEC) 708 fc = *fp++; 709 710 if (fc == '%') { 711 if (sz != NOTSPEC || left || sign || space || 712 alt || zero || prec || fwidth) { 713 badfmt(hte, call); 714 } 715 fc = *fp++; 716 continue; 717 } 718 719 if (fc == '\0') { 720 badfmt(hte, call); 721 break; 722 } 723 724 if ((tp = *ap++) == NULL) { 725 tofewarg(hte, call); 726 break; 727 } 728 n++; 729 if ((t1 = tp->t_tspec) == PTR) 730 t2 = tp->t_subt->t_tspec; 731 732 if (fc == 'd' || fc == 'i') { 733 if (alt || sz == LDOUBLE) { 734 badfmt(hte, call); 735 break; 736 } 737 int_conv: 738 if (sz == LONG) { 739 if (t1 != LONG && (hflag || t1 != ULONG)) 740 inconarg(hte, call, n); 741 } else if (sz == QUAD) { 742 if (t1 != QUAD && (hflag || t1 != UQUAD)) 743 inconarg(hte, call, n); 744 } else { 745 /* 746 * SHORT is always promoted to INT, USHORT 747 * to INT or UINT. 748 */ 749 if (t1 != INT && (hflag || t1 != UINT)) 750 inconarg(hte, call, n); 751 } 752 } else if (fc == 'o' || fc == 'u' || fc == 'x' || fc == 'X') { 753 if ((alt && fc == 'u') || sz == LDOUBLE) 754 badfmt(hte, call); 755 uint_conv: 756 if (sz == LONG) { 757 if (t1 != ULONG && (hflag || t1 != LONG)) 758 inconarg(hte, call, n); 759 } else if (sz == QUAD) { 760 if (t1 != UQUAD && (hflag || t1 != QUAD)) 761 inconarg(hte, call, n); 762 } else if (sz == SHORT) { 763 /* USHORT was promoted to INT or UINT */ 764 if (t1 != UINT && t1 != INT) 765 inconarg(hte, call, n); 766 } else { 767 if (t1 != UINT && (hflag || t1 != INT)) 768 inconarg(hte, call, n); 769 } 770 } else if (fc == 'D' || fc == 'O' || fc == 'U') { 771 if ((alt && fc != 'O') || sz != NOTSPEC || !tflag) 772 badfmt(hte, call); 773 sz = LONG; 774 if (fc == 'D') { 775 goto int_conv; 776 } else { 777 goto uint_conv; 778 } 779 } else if (fc == 'f' || fc == 'e' || fc == 'E' || 780 fc == 'g' || fc == 'G') { 781 if (sz == NOTSPEC) 782 sz = DOUBLE; 783 if (sz != DOUBLE && sz != LDOUBLE) 784 badfmt(hte, call); 785 if (t1 != sz) 786 inconarg(hte, call, n); 787 } else if (fc == 'c') { 788 if (sz != NOTSPEC || alt || zero) 789 badfmt(hte, call); 790 if (t1 != INT) 791 inconarg(hte, call, n); 792 } else if (fc == 's') { 793 if (sz != NOTSPEC || alt || zero) 794 badfmt(hte, call); 795 if (t1 != PTR || 796 (t2 != CHAR && t2 != UCHAR && t2 != SCHAR)) { 797 inconarg(hte, call, n); 798 } 799 } else if (fc == 'p') { 800 if (fwidth || prec || sz != NOTSPEC || alt || zero) 801 badfmt(hte, call); 802 if (t1 != PTR || (hflag && t2 != VOID)) 803 inconarg(hte, call, n); 804 } else if (fc == 'n') { 805 if (fwidth || prec || alt || zero || sz == LDOUBLE) 806 badfmt(hte, call); 807 if (t1 != PTR) { 808 inconarg(hte, call, n); 809 } else if (sz == LONG) { 810 if (t2 != LONG && t2 != ULONG) 811 inconarg(hte, call, n); 812 } else if (sz == SHORT) { 813 if (t2 != SHORT && t2 != USHORT) 814 inconarg(hte, call, n); 815 } else { 816 if (t2 != INT && t2 != UINT) 817 inconarg(hte, call, n); 818 } 819 } else { 820 badfmt(hte, call); 821 break; 822 } 823 824 fc = *fp++; 825 } 826 } 827 828 /* 829 * Compare the types in the NULL-terminated array ap with the format 830 * string fmt. 831 */ 832 static void 833 scanflike(const hte_t *hte, fcall_t *call, int n, const char *fmt, type_t **ap) 834 { 835 const char *fp; 836 char fc; 837 bool noasgn, fwidth; 838 tspec_t sz, t1 = NOTSPEC, t2 = NOTSPEC; 839 type_t *tp = NULL; 840 841 fp = fmt; 842 fc = *fp++; 843 844 for (;;) { 845 if (fc == '\0') { 846 if (*ap != NULL) 847 tomanyarg(hte, call); 848 break; 849 } 850 if (fc != '%') { 851 badfmt(hte, call); 852 break; 853 } 854 fc = *fp++; 855 856 noasgn = fwidth = false; 857 sz = NOTSPEC; 858 859 if (fc == '*') { 860 noasgn = true; 861 fc = *fp++; 862 } 863 864 if (ch_isdigit(fc)) { 865 fwidth = true; 866 do { fc = *fp++; } while (ch_isdigit(fc)); 867 } 868 869 if (fc == 'h') { 870 sz = SHORT; 871 } else if (fc == 'l') { 872 sz = LONG; 873 } else if (fc == 'q') { 874 sz = QUAD; 875 } else if (fc == 'L') { 876 sz = LDOUBLE; 877 } 878 if (sz != NOTSPEC) 879 fc = *fp++; 880 881 if (fc == '%') { 882 if (sz != NOTSPEC || noasgn || fwidth) 883 badfmt(hte, call); 884 fc = *fp++; 885 continue; 886 } 887 888 if (!noasgn) { 889 if ((tp = *ap++) == NULL) { 890 tofewarg(hte, call); 891 break; 892 } 893 n++; 894 if ((t1 = tp->t_tspec) == PTR) 895 t2 = tp->t_subt->t_tspec; 896 } 897 898 if (fc == 'd' || fc == 'i' || fc == 'n') { 899 if (sz == LDOUBLE) 900 badfmt(hte, call); 901 if (sz != SHORT && sz != LONG && sz != QUAD) 902 sz = INT; 903 conv: 904 if (!noasgn) { 905 if (t1 != PTR) { 906 inconarg(hte, call, n); 907 } else if (t2 != signed_type(sz)) { 908 inconarg(hte, call, n); 909 } else if (hflag && t2 != sz) { 910 inconarg(hte, call, n); 911 } else if (tp->t_subt->t_const) { 912 inconarg(hte, call, n); 913 } 914 } 915 } else if (fc == 'o' || fc == 'u' || fc == 'x') { 916 if (sz == LDOUBLE) 917 badfmt(hte, call); 918 if (sz == SHORT) { 919 sz = USHORT; 920 } else if (sz == LONG) { 921 sz = ULONG; 922 } else if (sz == QUAD) { 923 sz = UQUAD; 924 } else { 925 sz = UINT; 926 } 927 goto conv; 928 } else if (fc == 'D') { 929 if (sz != NOTSPEC || !tflag) 930 badfmt(hte, call); 931 sz = LONG; 932 goto conv; 933 } else if (fc == 'O') { 934 if (sz != NOTSPEC || !tflag) 935 badfmt(hte, call); 936 sz = ULONG; 937 goto conv; 938 } else if (fc == 'X') { 939 /* 940 * XXX valid in ANSI C, but in NetBSD's libc imple- 941 * mented as "lx". That's why it should be avoided. 942 */ 943 if (sz != NOTSPEC || !tflag) 944 badfmt(hte, call); 945 sz = ULONG; 946 goto conv; 947 } else if (fc == 'E') { 948 /* 949 * XXX valid in ANSI C, but in NetBSD's libc imple- 950 * mented as "lf". That's why it should be avoided. 951 */ 952 if (sz != NOTSPEC || !tflag) 953 badfmt(hte, call); 954 sz = DOUBLE; 955 goto conv; 956 } else if (fc == 'F') { 957 /* XXX only for backward compatibility */ 958 if (sz != NOTSPEC || !tflag) 959 badfmt(hte, call); 960 sz = DOUBLE; 961 goto conv; 962 } else if (fc == 'G') { 963 /* 964 * XXX valid in ANSI C, but in NetBSD's libc not 965 * implemented 966 */ 967 if (sz != NOTSPEC && sz != LONG && sz != LDOUBLE) 968 badfmt(hte, call); 969 goto fconv; 970 } else if (fc == 'e' || fc == 'f' || fc == 'g') { 971 fconv: 972 if (sz == NOTSPEC) { 973 sz = FLOAT; 974 } else if (sz == LONG) { 975 sz = DOUBLE; 976 } else if (sz != LDOUBLE) { 977 badfmt(hte, call); 978 sz = FLOAT; 979 } 980 goto conv; 981 } else if (fc == 's' || fc == '[' || fc == 'c') { 982 if (sz != NOTSPEC) 983 badfmt(hte, call); 984 if (fc == '[') { 985 if ((fc = *fp++) == '-') { 986 badfmt(hte, call); 987 fc = *fp++; 988 } 989 if (fc != ']') { 990 badfmt(hte, call); 991 if (fc == '\0') 992 break; 993 } 994 } 995 if (!noasgn) { 996 if (t1 != PTR) { 997 inconarg(hte, call, n); 998 } else if (t2 != CHAR && t2 != UCHAR && 999 t2 != SCHAR) { 1000 inconarg(hte, call, n); 1001 } 1002 } 1003 } else if (fc == 'p') { 1004 if (sz != NOTSPEC) 1005 badfmt(hte, call); 1006 if (!noasgn) { 1007 if (t1 != PTR || t2 != PTR) { 1008 inconarg(hte, call, n); 1009 } else if (tp->t_subt->t_subt->t_tspec!=VOID) { 1010 if (hflag) 1011 inconarg(hte, call, n); 1012 } 1013 } 1014 } else { 1015 badfmt(hte, call); 1016 break; 1017 } 1018 1019 fc = *fp++; 1020 } 1021 } 1022 1023 static void 1024 badfmt(const hte_t *hte, fcall_t *call) 1025 { 1026 1027 /* %s: malformed format string \t%s */ 1028 msg(13, hte->h_name, mkpos(&call->f_pos)); 1029 } 1030 1031 static void 1032 inconarg(const hte_t *hte, fcall_t *call, int n) 1033 { 1034 1035 /* %s, arg %d inconsistent with format \t%s */ 1036 msg(14, hte->h_name, n, mkpos(&call->f_pos)); 1037 } 1038 1039 static void 1040 tofewarg(const hte_t *hte, fcall_t *call) 1041 { 1042 1043 /* %s: too few args for format \t%s */ 1044 msg(15, hte->h_name, mkpos(&call->f_pos)); 1045 } 1046 1047 static void 1048 tomanyarg(const hte_t *hte, fcall_t *call) 1049 { 1050 1051 /* %s: too many args for format \t%s */ 1052 msg(16, hte->h_name, mkpos(&call->f_pos)); 1053 } 1054 1055 /* 1056 * List of functions where we usually don't care about their result. 1057 * NB: Must be sorted. 1058 */ 1059 static const char ignorelist[][8] = { 1060 "memcpy", 1061 "memmove", 1062 "memset", 1063 "printf", 1064 "strcat", 1065 "strcpy", 1066 "vprintf", 1067 }; 1068 1069 /* 1070 * Print warnings for return values which are used, but not returned, 1071 * or return values which are always or sometimes ignored. 1072 */ 1073 static void 1074 chkrvu(const hte_t *hte, sym_t *def) 1075 { 1076 fcall_t *call; 1077 bool used, ignored; 1078 1079 if (def == NULL) 1080 /* don't know whether or not the functions returns a value */ 1081 return; 1082 1083 if (hte->h_calls == NULL) 1084 return; 1085 1086 if (def->s_function_has_return_value) { 1087 /* 1088 * XXX as soon as we are able to disable single warnings, 1089 * the following dependencies from hflag should be removed. 1090 * But for now I don't want to be bothered by these warnings 1091 * which are almost always useless. 1092 */ 1093 if (!hflag) 1094 return; 1095 if (hflag && bsearch(hte->h_name, ignorelist, 1096 sizeof(ignorelist) / sizeof(ignorelist[0]), 1097 sizeof(ignorelist[0]), 1098 (int (*)(const void *, const void *))strcmp) != NULL) 1099 return; 1100 1101 /* function has return value */ 1102 used = ignored = false; 1103 for (call = hte->h_calls; call != NULL; call = call->f_next) { 1104 used |= call->f_rused || call->f_rdisc; 1105 ignored |= !call->f_rused && !call->f_rdisc; 1106 } 1107 if (!used && ignored) { 1108 /* %s returns value which is always ignored */ 1109 msg(8, hte->h_name); 1110 } else if (used && ignored) { 1111 /* %s returns value which is sometimes ignored */ 1112 msg(9, hte->h_name); 1113 } 1114 } else { 1115 /* function has no return value */ 1116 for (call = hte->h_calls; call != NULL; call = call->f_next) { 1117 if (call->f_rused) 1118 /* %s value is used( %s ), but none returned */ 1119 msg(10, hte->h_name, mkpos(&call->f_pos)); 1120 } 1121 } 1122 } 1123 1124 /* 1125 * Print warnings for inconsistent argument declarations. 1126 */ 1127 static void 1128 chkadecl(const hte_t *hte, sym_t *def, sym_t *decl) 1129 { 1130 bool osdef, eq, dowarn; 1131 int n; 1132 sym_t *sym1, *sym; 1133 type_t **ap1, **ap2, *tp1, *tp2; 1134 char *pos1; 1135 const char *pos2; 1136 1137 osdef = false; 1138 if (def != NULL) { 1139 osdef = def->s_old_style_function; 1140 sym1 = def; 1141 } else if (decl != NULL && TP(decl->s_type)->t_proto) { 1142 sym1 = decl; 1143 } else { 1144 return; 1145 } 1146 if (TP(sym1->s_type)->t_tspec != FUNC) 1147 return; 1148 1149 /* 1150 * XXX Prototypes should also be compared with old style function 1151 * declarations. 1152 */ 1153 1154 for (sym = hte->h_syms; sym != NULL; sym = sym->s_next) { 1155 if (sym == sym1 || !TP(sym->s_type)->t_proto) 1156 continue; 1157 ap1 = TP(sym1->s_type)->t_args; 1158 ap2 = TP(sym->s_type)->t_args; 1159 n = 0; 1160 while (*ap1 != NULL && *ap2 != NULL) { 1161 type_t *xt1, *xt2; 1162 dowarn = false; 1163 eq = types_compatible(xt1 = *ap1, xt2 = *ap2, 1164 true, osdef, false, &dowarn); 1165 if (!eq || dowarn) { 1166 pos1 = xstrdup(mkpos(&sym1->s_pos)); 1167 pos2 = mkpos(&sym->s_pos); 1168 /* %s, arg %d declared inconsistently ... */ 1169 msg(11, hte->h_name, n + 1, 1170 type_name(xt1), type_name(xt2), pos1, pos2); 1171 free(pos1); 1172 } 1173 n++; 1174 ap1++; 1175 ap2++; 1176 } 1177 if (*ap1 == *ap2) { 1178 tp1 = TP(sym1->s_type); 1179 tp2 = TP(sym->s_type); 1180 if (tp1->t_vararg == tp2->t_vararg) 1181 continue; 1182 if (tp2->t_vararg && sym1->s_check_only_first_args && 1183 sym1->s_check_num_args == n && !sflag) { 1184 continue; 1185 } 1186 } 1187 pos1 = xstrdup(mkpos(&sym1->s_pos)); 1188 /* %s: variable # of args declared \t%s :: %s */ 1189 msg(12, hte->h_name, pos1, mkpos(&sym->s_pos)); 1190 free(pos1); 1191 } 1192 } 1193 1194 1195 /* 1196 * Check compatibility of two types. Returns whether types are compatible. 1197 * 1198 * ignqual if set, ignore qualifiers of outermost type; used for 1199 * function arguments 1200 * promote if set, promote left type before comparison; used for 1201 * comparisons of arguments with parameters of old style 1202 * definitions 1203 * asgn left indirected type must have at least the same qualifiers 1204 * like right indirected type (for assignments and function 1205 * arguments) 1206 * *dowarn set to true if an old style declaration was compared with 1207 * an incompatible prototype declaration 1208 */ 1209 static bool 1210 types_compatible(type_t *tp1, type_t *tp2, 1211 bool ignqual, bool promot, bool asgn, bool *dowarn) 1212 { 1213 tspec_t t, to; 1214 int indir; 1215 1216 to = NOTSPEC; 1217 indir = 0; 1218 1219 while (tp1 != NULL && tp2 != NULL) { 1220 1221 t = tp1->t_tspec; 1222 if (promot) { 1223 if (t == FLOAT) { 1224 t = DOUBLE; 1225 } else if (t == CHAR || t == SCHAR) { 1226 t = INT; 1227 } else if (t == UCHAR) { 1228 t = tflag ? UINT : INT; 1229 } else if (t == SHORT) { 1230 t = INT; 1231 } else if (t == USHORT) { 1232 /* CONSTCOND */ 1233 t = INT_MAX < USHRT_MAX || tflag ? UINT : INT; 1234 } 1235 } 1236 1237 if (asgn && to == PTR) { 1238 if (indir == 1 && (t == VOID || tp2->t_tspec == VOID)) 1239 return true; 1240 } 1241 1242 if (t != tp2->t_tspec) { 1243 /* 1244 * Give pointer to types which differ only in 1245 * signedness a chance if not sflag and not hflag. 1246 */ 1247 if (sflag || hflag || to != PTR) 1248 return false; 1249 if (signed_type(t) != signed_type(tp2->t_tspec)) 1250 return false; 1251 } 1252 1253 if (tp1->t_is_enum && tp2->t_is_enum) { 1254 if (tp1->t_istag && tp2->t_istag) { 1255 return tp1->t_tag == tp2->t_tag; 1256 } else if (tp1->t_istynam && tp2->t_istynam) { 1257 return tp1->t_tynam == tp2->t_tynam; 1258 } else if (tp1->t_isuniqpos && tp2->t_isuniqpos) { 1259 return (tp1->t_uniqpos.p_line == 1260 tp2->t_uniqpos.p_line && 1261 tp1->t_uniqpos.p_file == 1262 tp2->t_uniqpos.p_file && 1263 tp1->t_uniqpos.p_uniq == 1264 tp2->t_uniqpos.p_uniq); 1265 } else { 1266 return false; 1267 } 1268 } 1269 1270 /* 1271 * XXX Handle combinations of enum and int if eflag is set. 1272 * But note: enum and 0 should be allowed. 1273 */ 1274 1275 if (asgn && indir == 1) { 1276 if (!tp1->t_const && tp2->t_const) 1277 return false; 1278 if (!tp1->t_volatile && tp2->t_volatile) 1279 return false; 1280 } else if (!ignqual && !tflag) { 1281 if (tp1->t_const != tp2->t_const) 1282 return false; 1283 if (tp1->t_const != tp2->t_const) 1284 return false; 1285 } 1286 1287 if (t == STRUCT || t == UNION) { 1288 if (tp1->t_istag && tp2->t_istag) { 1289 return tp1->t_tag == tp2->t_tag; 1290 } else if (tp1->t_istynam && tp2->t_istynam) { 1291 return tp1->t_tynam == tp2->t_tynam; 1292 } else if (tp1->t_isuniqpos && tp2->t_isuniqpos) { 1293 return (tp1->t_uniqpos.p_line == 1294 tp2->t_uniqpos.p_line && 1295 tp1->t_uniqpos.p_file == 1296 tp2->t_uniqpos.p_file && 1297 tp1->t_uniqpos.p_uniq == 1298 tp2->t_uniqpos.p_uniq); 1299 } else { 1300 return false; 1301 } 1302 } 1303 1304 if (t == ARRAY && tp1->t_dim != tp2->t_dim) { 1305 if (tp1->t_dim != 0 && tp2->t_dim != 0) 1306 return false; 1307 } 1308 1309 if (t == FUNC) { 1310 if (tp1->t_proto && tp2->t_proto) { 1311 if (!prototypes_compatible(tp1, tp2, dowarn)) 1312 return false; 1313 } else if (tp1->t_proto) { 1314 if (!matches_no_arg_function(tp1, dowarn)) 1315 return false; 1316 } else if (tp2->t_proto) { 1317 if (!matches_no_arg_function(tp2, dowarn)) 1318 return false; 1319 } 1320 } 1321 1322 tp1 = tp1->t_subt; 1323 tp2 = tp2->t_subt; 1324 ignqual = promot = false; 1325 to = t; 1326 indir++; 1327 1328 } 1329 1330 return tp1 == tp2; 1331 } 1332 1333 /* 1334 * Compares arguments of two prototypes 1335 */ 1336 static bool 1337 prototypes_compatible(type_t *tp1, type_t *tp2, bool *dowarn) 1338 { 1339 type_t **a1, **a2; 1340 1341 if (tp1->t_vararg != tp2->t_vararg) 1342 return false; 1343 1344 a1 = tp1->t_args; 1345 a2 = tp2->t_args; 1346 1347 while (*a1 != NULL && *a2 != NULL) { 1348 1349 if (!types_compatible(*a1, *a2, true, false, false, dowarn)) 1350 return false; 1351 1352 a1++; 1353 a2++; 1354 1355 } 1356 1357 return *a1 == *a2; 1358 } 1359 1360 /* 1361 * Returns whether all parameters of a prototype are compatible with an 1362 * old-style function declaration. 1363 * 1364 * This is the case if the following conditions are met: 1365 * 1. the prototype must have a fixed number of parameters 1366 * 2. no parameter is of type float 1367 * 3. no parameter is converted to another type if integer promotion 1368 * is applied on it 1369 */ 1370 static bool 1371 matches_no_arg_function(type_t *tp, bool *dowarn) 1372 { 1373 type_t **arg; 1374 tspec_t t; 1375 1376 if (tp->t_vararg && dowarn != NULL) 1377 *dowarn = true; 1378 for (arg = tp->t_args; *arg != NULL; arg++) { 1379 if ((t = (*arg)->t_tspec) == FLOAT) 1380 return false; 1381 if (t == CHAR || t == SCHAR || t == UCHAR) 1382 return false; 1383 if (t == SHORT || t == USHORT) 1384 return false; 1385 } 1386 return true; 1387 } 1388
Indexes created Tue Oct 14 21:09:58 GMT 2025