nsz Git - cparser/blob - format_check.c

   1 /*
   2  * This file is part of cparser.
   3  * Copyright (C) 2007-2008 Matthias Braun <matze@braunis.de>
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License
   7  * as published by the Free Software Foundation; either version 2
   8  * of the License, or (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  18  * 02111-1307, USA.
  19  */
  20 #include <ctype.h>
  21 #include <wctype.h>
  22
  23 #include "format_check.h"
  24 #include "symbol_t.h"
  25 #include "ast_t.h"
  26 #include "diagnostic.h"
  27 #include "types.h"
  28 #include "type_t.h"
  29 #include "warning.h"
  30 #include "lang_features.h"
  31
  32 typedef enum format_flag_t {
  33         FMT_FLAG_NONE  = 0,
  34         FMT_FLAG_HASH  = 1U << 0,
  35         FMT_FLAG_ZERO  = 1U << 1,
  36         FMT_FLAG_MINUS = 1U << 2,
  37         FMT_FLAG_SPACE = 1U << 3,
  38         FMT_FLAG_PLUS  = 1U << 4,
  39         FMT_FLAG_TICK  = 1U << 5
  40 } format_flag_t;
  41
  42 typedef unsigned format_flags_t;
  43
  44 typedef enum format_length_modifier_t {
  45         FMT_MOD_NONE,
  46         FMT_MOD_L,
  47         FMT_MOD_hh,
  48         FMT_MOD_h,
  49         FMT_MOD_l,
  50         FMT_MOD_ll,
  51         FMT_MOD_j,
  52         FMT_MOD_t,
  53         FMT_MOD_z,
  54         FMT_MOD_q,
  55         /* only in microsoft mode */
  56         FMT_MOD_w,
  57         FMT_MOD_I,
  58         FMT_MOD_I32,
  59         FMT_MOD_I64
  60 } format_length_modifier_t;
  61
  62 static const char* get_length_modifier_name(const format_length_modifier_t mod)
  63 {
  64         static const char* const names[] = {
  65                 [FMT_MOD_NONE] = "",
  66                 [FMT_MOD_L]    = "L",
  67                 [FMT_MOD_hh]   = "hh",
  68                 [FMT_MOD_h]    = "h",
  69                 [FMT_MOD_l]    = "l",
  70                 [FMT_MOD_ll]   = "ll",
  71                 [FMT_MOD_j]    = "j",
  72                 [FMT_MOD_t]    = "t",
  73                 [FMT_MOD_z]    = "z",
  74                 [FMT_MOD_q]    = "q",
  75                 /* only in microsoft mode */
  76                 [FMT_MOD_w]    = "w",
  77                 [FMT_MOD_I]    = "I",
  78                 [FMT_MOD_I32]  = "I32",
  79                 [FMT_MOD_I64]  = "I64"
  80         };
  81         assert(mod < sizeof(names) / sizeof(*names));
  82         return names[mod];
  83 }
  84
  85 static void warn_invalid_length_modifier(const source_position_t *pos,
  86                                          const format_length_modifier_t mod,
  87                                          const wchar_rep_t conversion)
  88 {
  89         warningf(pos,
  90                 "invalid length modifier '%s' for conversion specifier '%%%c'",
  91                 get_length_modifier_name(mod), conversion
  92         );
  93 }
  94
  95 typedef struct vchar_t vchar_t;
  96 struct vchar_t {
  97         const void *string;   /**< the string */
  98         size_t     position;  /**< current position */
  99         size_t     size;      /**< size of the string */
 100
 101         /** return the first character of the string and setthe position to 0. */
 102         unsigned (*first)(vchar_t *self);
 103         /** return the next character of the string */
 104         unsigned (*next)(vchar_t *self);
 105         /** return non_zero if the given character is a digit */
 106         int (*is_digit)(unsigned vchar);
 107 };
 108
 109 static unsigned string_first(vchar_t *self) {
 110         self->position = 0;
 111         const string_t *string = self->string;
 112         return string->begin[0];
 113 }
 114
 115 static unsigned string_next(vchar_t *self) {
 116         ++self->position;
 117         const string_t *string = self->string;
 118         return string->begin[self->position];
 119 }
 120
 121 static int string_isdigit(unsigned vchar) {
 122         return isdigit(vchar);
 123 }
 124
 125 static unsigned wstring_first(vchar_t *self) {
 126         self->position = 0;
 127         const wide_string_t *wstring = self->string;
 128         return wstring->begin[0];
 129 }
 130
 131 static unsigned wstring_next(vchar_t *self) {
 132         ++self->position;
 133         const wide_string_t *wstring = self->string;
 134         return wstring->begin[self->position];
 135 }
 136
 137 static int wstring_isdigit(unsigned vchar) {
 138         return iswdigit(vchar);
 139 }
 140
 141 static bool atend(vchar_t *self) {
 142         return self->position + 1 == self->size;
 143 }
 144
 145 /**
 146  * Check printf-style format.
 147  */
 148 static void check_format_arguments(const call_argument_t *arg, unsigned idx_fmt, unsigned idx_param)
 149 {
 150         const call_argument_t *fmt_arg;
 151         unsigned idx = 0;
 152
 153         /* find format arg */
 154         for(idx = 0; idx < idx_fmt; ++idx)
 155                 arg = arg->next;
 156         fmt_arg = arg;
 157
 158         const expression_t *fmt_expr = fmt_arg->expression;
 159         if (fmt_expr->kind == EXPR_UNARY_CAST_IMPLICIT) {
 160                 fmt_expr = fmt_expr->unary.value;
 161         }
 162
 163         vchar_t vchar;
 164         if (fmt_expr->kind == EXPR_WIDE_STRING_LITERAL) {
 165                 vchar.string   = &fmt_expr->wide_string.value;
 166                 vchar.size     = fmt_expr->wide_string.value.size;
 167                 vchar.first    = wstring_first;
 168                 vchar.next     = wstring_next;
 169                 vchar.is_digit = wstring_isdigit;
 170         } else if (fmt_expr->kind == EXPR_STRING_LITERAL) {
 171                 vchar.string   = &fmt_expr->string.value;
 172                 vchar.size     = fmt_expr->string.value.size;
 173                 vchar.first    = string_first;
 174                 vchar.next     = string_next;
 175                 vchar.is_digit = string_isdigit;
 176         } else {
 177                 return;
 178         }
 179         /* find the real args */
 180         for(; idx < idx_fmt; ++idx)
 181                 arg = arg->next;
 182
 183         const source_position_t *pos = &fmt_expr->base.source_position;
 184         unsigned fmt = vchar.first(&vchar);
 185         for (; fmt != '\0'; fmt = vchar.next(&vchar)) {
 186                 if (fmt != '%')
 187                         continue;
 188                 fmt = vchar.next(&vchar);
 189
 190                 if (fmt == '%')
 191                         continue;
 192
 193                 format_flags_t fmt_flags = FMT_FLAG_NONE;
 194                 if (fmt == '0') {
 195                         fmt = vchar.next(&vchar);
 196                         fmt_flags |= FMT_FLAG_ZERO;
 197                 }
 198
 199                 /* argument selector or minimum field width */
 200                 if (vchar.is_digit(fmt)) {
 201                         do {
 202                                 fmt = vchar.next(&vchar);
 203                         } while (vchar.is_digit(fmt));
 204
 205                         /* digit string was ... */
 206                         if (fmt == '$') {
 207                                 /* ... argument selector */
 208                                 fmt_flags = FMT_FLAG_NONE; /* reset possibly set 0-flag */
 209                                 /* TODO implement */
 210                                 return;
 211                         }
 212                         /* ... minimum field width */
 213                 } else {
 214                         /* flags */
 215                         for (;;) {
 216                                 format_flags_t flag;
 217                                 switch (fmt) {
 218                                         case '#':  flag = FMT_FLAG_HASH;  break;
 219                                         case '0':  flag = FMT_FLAG_ZERO;  break;
 220                                         case '-':  flag = FMT_FLAG_MINUS; break;
 221                                         case '\'': flag = FMT_FLAG_TICK;  break;
 222
 223                                         case ' ':
 224                                                 if (fmt_flags & FMT_FLAG_PLUS) {
 225                                                         warningf(pos, "' ' is overridden by prior '+' in conversion specification");
 226                                                 }
 227                                                 flag = FMT_FLAG_SPACE;
 228                                                 break;
 229
 230                                         case '+':
 231                                                 if (fmt_flags & FMT_FLAG_SPACE) {
 232                                                         warningf(pos, "'+' overrides prior ' ' in conversion specification");
 233                                                 }
 234                                                 flag = FMT_FLAG_PLUS;
 235                                                 break;
 236
 237                                         default: goto break_fmt_flags;
 238                                 }
 239                                 if (fmt_flags & flag) {
 240                                         warningf(pos, "repeated flag '%c' in conversion specification", (char)fmt);
 241                                 }
 242                                 fmt_flags |= flag;
 243                                 fmt = vchar.next(&vchar);
 244                         }
 245 break_fmt_flags:
 246
 247                         /* minimum field width */
 248                         if (fmt == '*') {
 249                                 if (arg == NULL) {
 250                                         warningf(pos, "missing argument for '*' field width in conversion specification");
 251                                         return;
 252                                 }
 253                                 const type_t *const arg_type = arg->expression->base.type;
 254                                 if (arg_type != type_int) {
 255                                         warningf(pos, "argument for '*' field width in conversion specification is not an 'int', but an '%T'", arg_type);
 256                                 }
 257                                 arg = arg->next;
 258                         } else {
 259                                 while (vchar.is_digit(fmt)) {
 260                                         fmt = vchar.next(&vchar);
 261                                 }
 262                         }
 263                 }
 264
 265                 /* precision */
 266                 if (fmt == '.') {
 267                         fmt = vchar.next(&vchar);
 268                         if (fmt == '*') {
 269                                 if (arg == NULL) {
 270                                         warningf(pos, "missing argument for '*' precision in conversion specification");
 271                                         return;
 272                                 }
 273                                 const type_t *const arg_type = arg->expression->base.type;
 274                                 if (arg_type != type_int) {
 275                                         warningf(pos, "argument for '*' precision in conversion specification is not an 'int', but an '%T'", arg_type);
 276                                 }
 277                                 arg = arg->next;
 278                         } else {
 279                                 /* digit string may be omitted */
 280                                 while (vchar.is_digit(fmt)) {
 281                                         fmt = vchar.next(&vchar);
 282                                 }
 283                         }
 284                 }
 285
 286                 /* length modifier */
 287                 format_length_modifier_t fmt_mod;
 288                 switch (fmt) {
 289                         case 'h':
 290                                 fmt = vchar.next(&vchar);
 291                                 if (fmt == 'h') {
 292                                         fmt = vchar.next(&vchar);
 293                                         fmt_mod = FMT_MOD_hh;
 294                                 } else {
 295                                         fmt_mod = FMT_MOD_h;
 296                                 }
 297                                 break;
 298
 299                         case 'l':
 300                                 fmt = vchar.next(&vchar);
 301                                 if (fmt == 'l') {
 302                                         fmt = vchar.next(&vchar);
 303                                         fmt_mod = FMT_MOD_ll;
 304                                 } else {
 305                                         fmt_mod = FMT_MOD_l;
 306                                 }
 307                                 break;
 308
 309                         case 'L': fmt = vchar.next(&vchar); fmt_mod = FMT_MOD_L;    break;
 310                         case 'j': fmt = vchar.next(&vchar); fmt_mod = FMT_MOD_j;    break;
 311                         case 't': fmt = vchar.next(&vchar); fmt_mod = FMT_MOD_t;    break;
 312                         case 'z': fmt = vchar.next(&vchar); fmt_mod = FMT_MOD_z;    break;
 313                         case 'q': fmt = vchar.next(&vchar); fmt_mod = FMT_MOD_q;    break;
 314                         /* microsoft mode */
 315                         case 'w':
 316                                 if (c_mode & _MS) {
 317                                         fmt = vchar.next(&vchar); fmt_mod = FMT_MOD_w;
 318                                 } else {
 319                                         fmt_mod = FMT_MOD_NONE;
 320                                 }
 321                                 break;
 322                         case 'I':
 323                                 if (c_mode & _MS) {
 324                                         fmt = vchar.next(&vchar); fmt_mod = FMT_MOD_I;
 325                                         if (fmt == '3') {
 326                                                 fmt = vchar.next(&vchar);
 327                                                 if (fmt == '2') {
 328                                                         fmt = vchar.next(&vchar);
 329                                                         fmt_mod = FMT_MOD_I32;
 330                                                 } else {
 331                                                         /* rewind */
 332                                                         --vchar.position;
 333                                                 }
 334                                         } else if (fmt == '6') {
 335                                                 fmt = vchar.next(&vchar);
 336                                                 if (fmt == '4') {
 337                                                         fmt = vchar.next(&vchar);
 338                                                         fmt_mod = FMT_MOD_I64;
 339                                                 } else {
 340                                                         /* rewind */
 341                                                         --vchar.position;
 342                                                 }
 343                                         }
 344                                 } else {
 345                                         fmt_mod = FMT_MOD_NONE;
 346                                 }
 347                                 break;
 348                         default:
 349                                 fmt_mod = FMT_MOD_NONE;
 350                                 break;
 351                 }
 352
 353                 if (fmt == '\0') {
 354                         warningf(pos, "dangling %% in format string");
 355                         break;
 356                 }
 357
 358                 const type_t      *expected_type;
 359                 type_qualifiers_t  expected_qual = TYPE_QUALIFIER_NONE;
 360                 format_flags_t     allowed_flags;
 361                 switch (fmt) {
 362                         case 'd':
 363                         case 'i':
 364                                 switch (fmt_mod) {
 365                                         case FMT_MOD_NONE: expected_type = type_int;       break;
 366                                         case FMT_MOD_hh:   expected_type = type_int;       break; /* TODO promoted signed char */
 367                                         case FMT_MOD_h:    expected_type = type_int;       break; /* TODO promoted short */
 368                                         case FMT_MOD_l:    expected_type = type_long;      break;
 369                                         case FMT_MOD_ll:   expected_type = type_long_long; break;
 370                                         case FMT_MOD_j:    expected_type = type_intmax_t;  break;
 371                                         case FMT_MOD_z:    expected_type = type_ssize_t;   break;
 372                                         case FMT_MOD_t:    expected_type = type_ptrdiff_t; break;
 373                                         case FMT_MOD_I:    expected_type = type_ptrdiff_t; break;
 374                                         case FMT_MOD_I32:  expected_type = type_int32;     break;
 375                                         case FMT_MOD_I64:  expected_type = type_int64;     break;
 376
 377                                         default:
 378                                                 warn_invalid_length_modifier(pos, fmt_mod, fmt);
 379                                                 goto next_arg;
 380                                 }
 381                                 allowed_flags = FMT_FLAG_MINUS | FMT_FLAG_SPACE | FMT_FLAG_PLUS | FMT_FLAG_ZERO;
 382                                 break;
 383
 384                         case 'o':
 385                         case 'X':
 386                         case 'x':
 387                                 allowed_flags = FMT_FLAG_MINUS | FMT_FLAG_HASH | FMT_FLAG_ZERO;
 388                                 goto eval_fmt_mod_unsigned;
 389                                 break;
 390
 391                         case 'u':
 392                                 allowed_flags = FMT_FLAG_MINUS | FMT_FLAG_ZERO;
 393 eval_fmt_mod_unsigned:
 394                                 switch (fmt_mod) {
 395                                         case FMT_MOD_NONE: expected_type = type_unsigned_int;       break;
 396                                         case FMT_MOD_hh:   expected_type = type_int;                break; /* TODO promoted unsigned char */
 397                                         case FMT_MOD_h:    expected_type = type_int;                break; /* TODO promoted unsigned short */
 398                                         case FMT_MOD_l:    expected_type = type_unsigned_long;      break;
 399                                         case FMT_MOD_ll:   expected_type = type_unsigned_long_long; break;
 400                                         case FMT_MOD_j:    expected_type = type_uintmax_t;          break;
 401                                         case FMT_MOD_z:    expected_type = type_size_t;             break;
 402                                         case FMT_MOD_t:    expected_type = type_uptrdiff_t;         break;
 403                                         case FMT_MOD_I:    expected_type = type_size_t;             break;
 404                                         case FMT_MOD_I32:  expected_type = type_unsigned_int32;     break;
 405                                         case FMT_MOD_I64:  expected_type = type_unsigned_int64;     break;
 406
 407                                         default:
 408                                                 warn_invalid_length_modifier(pos, fmt_mod, fmt);
 409                                                 goto next_arg;
 410                                 }
 411                                 break;
 412
 413                         case 'A':
 414                         case 'a':
 415                         case 'E':
 416                         case 'e':
 417                         case 'F':
 418                         case 'f':
 419                         case 'G':
 420                         case 'g':
 421                                 switch (fmt_mod) {
 422                                         case FMT_MOD_l:    /* l modifier is ignored */
 423                                         case FMT_MOD_NONE: expected_type = type_double;      break;
 424                                         case FMT_MOD_L:    expected_type = type_long_double; break;
 425
 426                                         default:
 427                                                 warn_invalid_length_modifier(pos, fmt_mod, fmt);
 428                                                 goto next_arg;
 429                                 }
 430                                 allowed_flags = FMT_FLAG_MINUS | FMT_FLAG_SPACE | FMT_FLAG_PLUS | FMT_FLAG_HASH | FMT_FLAG_ZERO;
 431                                 break;
 432
 433                         case 'C':
 434                                 if (fmt_mod != FMT_MOD_NONE) {
 435                                         warn_invalid_length_modifier(pos, fmt_mod, fmt);
 436                                         goto next_arg;
 437                                 }
 438                                 expected_type = type_wchar_t;
 439                                 allowed_flags = FMT_FLAG_NONE;
 440                                 break;
 441
 442                         case 'c':
 443                                 expected_type = type_int;
 444                                 switch (fmt_mod) {
 445                                         case FMT_MOD_NONE: expected_type = type_int;     break; /* TODO promoted char */
 446                                         case FMT_MOD_l:    expected_type = type_wint_t;  break;
 447                                         case FMT_MOD_w:    expected_type = type_wchar_t; break;
 448
 449                                         default:
 450                                                 warn_invalid_length_modifier(pos, fmt_mod, fmt);
 451                                                 goto next_arg;
 452                                 }
 453                                 allowed_flags = FMT_FLAG_NONE;
 454                                 break;
 455
 456                         case 'S':
 457                                 if (fmt_mod != FMT_MOD_NONE) {
 458                                         warn_invalid_length_modifier(pos, fmt_mod, fmt);
 459                                         goto next_arg;
 460                                 }
 461                                 expected_type = type_wchar_t_ptr;
 462                                 expected_qual = TYPE_QUALIFIER_CONST;
 463                                 allowed_flags = FMT_FLAG_NONE;
 464                                 break;
 465
 466                         case 's':
 467                                 switch (fmt_mod) {
 468                                         case FMT_MOD_NONE: expected_type = type_char_ptr;    break;
 469                                         case FMT_MOD_l:    expected_type = type_wchar_t_ptr; break;
 470                                         case FMT_MOD_w:    expected_type = type_wchar_t_ptr; break;
 471
 472                                         default:
 473                                                 warn_invalid_length_modifier(pos, fmt_mod, fmt);
 474                                                 goto next_arg;
 475                                 }
 476                                 expected_qual = TYPE_QUALIFIER_CONST;
 477                                 allowed_flags = FMT_FLAG_NONE;
 478                                 break;
 479
 480                         case 'p':
 481                                 if (fmt_mod != FMT_MOD_NONE) {
 482                                         warn_invalid_length_modifier(pos, fmt_mod, fmt);
 483                                         goto next_arg;
 484                                 }
 485                                 expected_type = type_void_ptr;
 486                                 allowed_flags = FMT_FLAG_NONE;
 487                                 break;
 488
 489                         case 'n':
 490                                 switch (fmt_mod) {
 491                                         case FMT_MOD_NONE: expected_type = type_int_ptr;         break;
 492                                         case FMT_MOD_hh:   expected_type = type_signed_char_ptr; break;
 493                                         case FMT_MOD_h:    expected_type = type_short_ptr;       break;
 494                                         case FMT_MOD_l:    expected_type = type_long_ptr;        break;
 495                                         case FMT_MOD_ll:   expected_type = type_long_long_ptr;   break;
 496                                         case FMT_MOD_j:    expected_type = type_intmax_t_ptr;    break;
 497                                         case FMT_MOD_z:    expected_type = type_ssize_t_ptr;     break;
 498                                         case FMT_MOD_t:    expected_type = type_ptrdiff_t_ptr;   break;
 499
 500                                         default:
 501                                                 warn_invalid_length_modifier(pos, fmt_mod, fmt);
 502                                                 goto next_arg;
 503                                 }
 504                                 allowed_flags = FMT_FLAG_NONE;
 505                                 break;
 506
 507                         default:
 508                                 warningf(pos, "encountered unknown conversion specifier '%%%C'", (wint_t)fmt);
 509                                 goto next_arg;
 510                 }
 511
 512                 if ((fmt_flags & ~allowed_flags) != 0) {
 513                         /* TODO better warning message text */
 514                         warningf(pos, "invalid format flags in conversion specification");
 515                 }
 516
 517                 if (arg == NULL) {
 518                         warningf(pos, "too few arguments for format string");
 519                         return;
 520                 }
 521
 522                 {       /* create a scope here to prevent warning about the jump to next_arg */
 523                         type_t *const arg_type = arg->expression->base.type;
 524                         if (is_type_pointer(expected_type)) {
 525                                 type_t *const arg_skip = skip_typeref(arg_type);
 526                                 if (is_type_pointer(arg_skip)) {
 527                                         type_t *const exp_to = skip_typeref(expected_type->pointer.points_to);
 528                                         type_t *const arg_to = skip_typeref(arg_skip->pointer.points_to);
 529                                         if ((arg_to->base.qualifiers & ~expected_qual) == 0 &&
 530                                                 get_unqualified_type(arg_to) == exp_to) {
 531                                                 goto next_arg;
 532                                         }
 533                                 }
 534                         } else {
 535                                 if (get_unqualified_type(skip_typeref(arg_type)) == expected_type) {
 536                                         goto next_arg;
 537                                 }
 538                         }
 539                         if (is_type_valid(arg_type)) {
 540                                 warningf(pos,
 541                                         "argument type '%T' does not match conversion specifier '%%%s%c'",
 542                                         arg_type, get_length_modifier_name(fmt_mod), (char)fmt);
 543                         }
 544                 }
 545 next_arg:
 546                 arg = arg->next;
 547         }
 548         if (!atend(&vchar)) {
 549                 warningf(pos, "format string contains NUL");
 550         }
 551         if (arg != NULL) {
 552                 warningf(pos, "too many arguments for format string");
 553         }
 554 }
 555
 556 static const struct {
 557         const char    *name;
 558         format_kind_t  fmt_kind;
 559         unsigned       fmt_idx;
 560         unsigned       arg_idx;
 561 } builtin_table[] = {
 562         { "printf",        FORMAT_PRINTF,   0, 1 },
 563         { "wprintf",       FORMAT_PRINTF,   0, 1 },
 564         { "sprintf",       FORMAT_PRINTF,   1, 2 },
 565         { "swprintf",      FORMAT_PRINTF,   1, 2 },
 566         { "snprintf",      FORMAT_PRINTF,   2, 3 },
 567         { "snwprintf",     FORMAT_PRINTF,   2, 3 },
 568         { "fprintf",       FORMAT_PRINTF,   1, 2 },
 569         { "fwprintf",      FORMAT_PRINTF,   1, 2 },
 570         { "snwprintf",     FORMAT_PRINTF,   2, 3 },
 571         { "snwprintf",     FORMAT_PRINTF,   2, 3 },
 572
 573         { "scanf",         FORMAT_SCANF,    0, 1 },
 574         { "wscanf",        FORMAT_SCANF,    0, 1 },
 575         { "sscanf",        FORMAT_SCANF,    1, 2 },
 576         { "swscanf",       FORMAT_SCANF,    1, 2 },
 577         { "fscanf",        FORMAT_SCANF,    1, 2 },
 578         { "fwscanf",       FORMAT_SCANF,    1, 2 },
 579
 580         { "strftime",      FORMAT_STRFTIME, 3, 4 },
 581         { "wcstrftime",    FORMAT_STRFTIME, 3, 4 },
 582
 583         { "strfmon",       FORMAT_STRFMON,  3, 4 },
 584
 585         /* MS extensions */
 586         { "_snprintf",     FORMAT_PRINTF,   2, 3 },
 587         { "_snwprintf",    FORMAT_PRINTF,   2, 3 },
 588         { "_scrintf",      FORMAT_PRINTF,   0, 1 },
 589         { "_scwprintf",    FORMAT_PRINTF,   0, 1 },
 590         { "printf_s",      FORMAT_PRINTF,   0, 1 },
 591         { "wprintf_s",     FORMAT_PRINTF,   0, 1 },
 592         { "sprintf_s",     FORMAT_PRINTF,   3, 4 },
 593         { "swprintf_s",    FORMAT_PRINTF,   3, 4 },
 594         { "fprintf_s",     FORMAT_PRINTF,   1, 2 },
 595         { "fwprintf_s",    FORMAT_PRINTF,   1, 2 },
 596         { "_sprintf_l",    FORMAT_PRINTF,   1, 3 },
 597         { "_swprintf_l",   FORMAT_PRINTF,   1, 3 },
 598         { "_printf_l",     FORMAT_PRINTF,   0, 2 },
 599         { "_wprintf_l",    FORMAT_PRINTF,   0, 2 },
 600         { "_fprintf_l",    FORMAT_PRINTF,   1, 3 },
 601         { "_fwprintf_l",   FORMAT_PRINTF,   1, 3 },
 602         { "_printf_s_l",   FORMAT_PRINTF,   0, 2 },
 603         { "_wprintf_s_l",  FORMAT_PRINTF,   0, 2 },
 604         { "_sprintf_s_l",  FORMAT_PRINTF,   3, 5 },
 605         { "_swprintf_s_l", FORMAT_PRINTF,   3, 5 },
 606         { "_fprintf_s_l",  FORMAT_PRINTF,   1, 3 },
 607         { "_fwprintf_s_l", FORMAT_PRINTF,   1, 3 },
 608 };
 609
 610 void check_format(const call_expression_t *const call)
 611 {
 612         if (!warning.format)
 613                 return;
 614
 615         const expression_t *const func_expr = call->function;
 616         if (func_expr->kind != EXPR_REFERENCE)
 617                 return;
 618
 619         const declaration_t   *const decl = func_expr->reference.declaration;
 620         const call_argument_t *      arg  = call->arguments;
 621
 622         if(false) {
 623                 /* the declaration has a GNU format attribute, check it */
 624         } else {
 625                 /*
 626                  * For some functions we always check the format, even if it was not specified.
 627                  * This allows to check format even in MS mode or without header included.
 628                  */
 629                 const char            *const name = decl->symbol->string;
 630                 for(size_t i = 0; i < sizeof(builtin_table) / sizeof(builtin_table[0]); ++i) {
 631                         if(strcmp(name, builtin_table[i].name) == 0) {
 632                                 if(builtin_table[i].fmt_kind == FORMAT_PRINTF) {
 633                                         check_format_arguments(arg,
 634                                                                                    builtin_table[i].fmt_idx,
 635                                                                                    builtin_table[i].arg_idx);
 636                                 }
 637                                 break;
 638                         }
 639                 }
 640         }
 641 }