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,
 149                 unsigned idx_param)
 150 {
 151         const call_argument_t *fmt_arg;
 152         unsigned idx = 0;
 153
 154         /* find format arg */
 155         for(idx = 0; idx < idx_fmt; ++idx)
 156                 arg = arg->next;
 157         fmt_arg = arg;
 158
 159         const expression_t *fmt_expr = fmt_arg->expression;
 160         if (fmt_expr->kind == EXPR_UNARY_CAST_IMPLICIT) {
 161                 fmt_expr = fmt_expr->unary.value;
 162         }
 163
 164         vchar_t vchar;
 165         if (fmt_expr->kind == EXPR_WIDE_STRING_LITERAL) {
 166                 vchar.string   = &fmt_expr->wide_string.value;
 167                 vchar.size     = fmt_expr->wide_string.value.size;
 168                 vchar.first    = wstring_first;
 169                 vchar.next     = wstring_next;
 170                 vchar.is_digit = wstring_isdigit;
 171         } else if (fmt_expr->kind == EXPR_STRING_LITERAL) {
 172                 vchar.string   = &fmt_expr->string.value;
 173                 vchar.size     = fmt_expr->string.value.size;
 174                 vchar.first    = string_first;
 175                 vchar.next     = string_next;
 176                 vchar.is_digit = string_isdigit;
 177         } else {
 178                 return;
 179         }
 180         /* find the real args */
 181         for(; idx < idx_param; ++idx)
 182                 arg = arg->next;
 183
 184         const source_position_t *pos = &fmt_expr->base.source_position;
 185         unsigned fmt = vchar.first(&vchar);
 186         for (; fmt != '\0'; fmt = vchar.next(&vchar)) {
 187                 if (fmt != '%')
 188                         continue;
 189                 fmt = vchar.next(&vchar);
 190
 191                 if (fmt == '%')
 192                         continue;
 193
 194                 format_flags_t fmt_flags = FMT_FLAG_NONE;
 195                 if (fmt == '0') {
 196                         fmt = vchar.next(&vchar);
 197                         fmt_flags |= FMT_FLAG_ZERO;
 198                 }
 199
 200                 /* argument selector or minimum field width */
 201                 if (vchar.is_digit(fmt)) {
 202                         do {
 203                                 fmt = vchar.next(&vchar);
 204                         } while (vchar.is_digit(fmt));
 205
 206                         /* digit string was ... */
 207                         if (fmt == '$') {
 208                                 /* ... argument selector */
 209                                 fmt_flags = FMT_FLAG_NONE; /* reset possibly set 0-flag */
 210                                 /* TODO implement */
 211                                 return;
 212                         }
 213                         /* ... minimum field width */
 214                 } else {
 215                         /* flags */
 216                         for (;;) {
 217                                 format_flags_t flag;
 218                                 switch (fmt) {
 219                                         case '#':  flag = FMT_FLAG_HASH;  break;
 220                                         case '0':  flag = FMT_FLAG_ZERO;  break;
 221                                         case '-':  flag = FMT_FLAG_MINUS; break;
 222                                         case '\'': flag = FMT_FLAG_TICK;  break;
 223
 224                                         case ' ':
 225                                                 if (fmt_flags & FMT_FLAG_PLUS) {
 226                                                         warningf(pos, "' ' is overridden by prior '+' in conversion specification");
 227                                                 }
 228                                                 flag = FMT_FLAG_SPACE;
 229                                                 break;
 230
 231                                         case '+':
 232                                                 if (fmt_flags & FMT_FLAG_SPACE) {
 233                                                         warningf(pos, "'+' overrides prior ' ' in conversion specification");
 234                                                 }
 235                                                 flag = FMT_FLAG_PLUS;
 236                                                 break;
 237
 238                                         default: goto break_fmt_flags;
 239                                 }
 240                                 if (fmt_flags & flag) {
 241                                         warningf(pos, "repeated flag '%c' in conversion specification", (char)fmt);
 242                                 }
 243                                 fmt_flags |= flag;
 244                                 fmt = vchar.next(&vchar);
 245                         }
 246 break_fmt_flags:
 247
 248                         /* minimum field width */
 249                         if (fmt == '*') {
 250                                 if (arg == NULL) {
 251                                         warningf(pos, "missing argument for '*' field width in conversion specification");
 252                                         return;
 253                                 }
 254                                 const type_t *const arg_type = arg->expression->base.type;
 255                                 if (arg_type != type_int) {
 256                                         warningf(pos, "argument for '*' field width in conversion specification is not an 'int', but an '%T'", arg_type);
 257                                 }
 258                                 arg = arg->next;
 259                         } else {
 260                                 while (vchar.is_digit(fmt)) {
 261                                         fmt = vchar.next(&vchar);
 262                                 }
 263                         }
 264                 }
 265
 266                 /* precision */
 267                 if (fmt == '.') {
 268                         fmt = vchar.next(&vchar);
 269                         if (fmt == '*') {
 270                                 if (arg == NULL) {
 271                                         warningf(pos, "missing argument for '*' precision in conversion specification");
 272                                         return;
 273                                 }
 274                                 const type_t *const arg_type = arg->expression->base.type;
 275                                 if (arg_type != type_int) {
 276                                         warningf(pos, "argument for '*' precision in conversion specification is not an 'int', but an '%T'", arg_type);
 277                                 }
 278                                 arg = arg->next;
 279                         } else {
 280                                 /* digit string may be omitted */
 281                                 while (vchar.is_digit(fmt)) {
 282                                         fmt = vchar.next(&vchar);
 283                                 }
 284                         }
 285                 }
 286
 287                 /* length modifier */
 288                 format_length_modifier_t fmt_mod;
 289                 switch (fmt) {
 290                         case 'h':
 291                                 fmt = vchar.next(&vchar);
 292                                 if (fmt == 'h') {
 293                                         fmt = vchar.next(&vchar);
 294                                         fmt_mod = FMT_MOD_hh;
 295                                 } else {
 296                                         fmt_mod = FMT_MOD_h;
 297                                 }
 298                                 break;
 299
 300                         case 'l':
 301                                 fmt = vchar.next(&vchar);
 302                                 if (fmt == 'l') {
 303                                         fmt = vchar.next(&vchar);
 304                                         fmt_mod = FMT_MOD_ll;
 305                                 } else {
 306                                         fmt_mod = FMT_MOD_l;
 307                                 }
 308                                 break;
 309
 310                         case 'L': fmt = vchar.next(&vchar); fmt_mod = FMT_MOD_L;    break;
 311                         case 'j': fmt = vchar.next(&vchar); fmt_mod = FMT_MOD_j;    break;
 312                         case 't': fmt = vchar.next(&vchar); fmt_mod = FMT_MOD_t;    break;
 313                         case 'z': fmt = vchar.next(&vchar); fmt_mod = FMT_MOD_z;    break;
 314                         case 'q': fmt = vchar.next(&vchar); fmt_mod = FMT_MOD_q;    break;
 315                         /* microsoft mode */
 316                         case 'w':
 317                                 if (c_mode & _MS) {
 318                                         fmt = vchar.next(&vchar); fmt_mod = FMT_MOD_w;
 319                                 } else {
 320                                         fmt_mod = FMT_MOD_NONE;
 321                                 }
 322                                 break;
 323                         case 'I':
 324                                 if (c_mode & _MS) {
 325                                         fmt = vchar.next(&vchar); fmt_mod = FMT_MOD_I;
 326                                         if (fmt == '3') {
 327                                                 fmt = vchar.next(&vchar);
 328                                                 if (fmt == '2') {
 329                                                         fmt = vchar.next(&vchar);
 330                                                         fmt_mod = FMT_MOD_I32;
 331                                                 } else {
 332                                                         /* rewind */
 333                                                         --vchar.position;
 334                                                 }
 335                                         } else if (fmt == '6') {
 336                                                 fmt = vchar.next(&vchar);
 337                                                 if (fmt == '4') {
 338                                                         fmt = vchar.next(&vchar);
 339                                                         fmt_mod = FMT_MOD_I64;
 340                                                 } else {
 341                                                         /* rewind */
 342                                                         --vchar.position;
 343                                                 }
 344                                         }
 345                                 } else {
 346                                         fmt_mod = FMT_MOD_NONE;
 347                                 }
 348                                 break;
 349                         default:
 350                                 fmt_mod = FMT_MOD_NONE;
 351                                 break;
 352                 }
 353
 354                 if (fmt == '\0') {
 355                         warningf(pos, "dangling %% in format string");
 356                         break;
 357                 }
 358
 359                 const type_t      *expected_type;
 360                 type_qualifiers_t  expected_qual = TYPE_QUALIFIER_NONE;
 361                 format_flags_t     allowed_flags;
 362                 switch (fmt) {
 363                         case 'd':
 364                         case 'i':
 365                                 switch (fmt_mod) {
 366                                         case FMT_MOD_NONE: expected_type = type_int;       break;
 367                                         case FMT_MOD_hh:   expected_type = type_int;       break; /* TODO promoted signed char */
 368                                         case FMT_MOD_h:    expected_type = type_int;       break; /* TODO promoted short */
 369                                         case FMT_MOD_l:    expected_type = type_long;      break;
 370                                         case FMT_MOD_ll:   expected_type = type_long_long; break;
 371                                         case FMT_MOD_j:    expected_type = type_intmax_t;  break;
 372                                         case FMT_MOD_z:    expected_type = type_ssize_t;   break;
 373                                         case FMT_MOD_t:    expected_type = type_ptrdiff_t; break;
 374                                         case FMT_MOD_I:    expected_type = type_ptrdiff_t; break;
 375                                         case FMT_MOD_I32:  expected_type = type_int32;     break;
 376                                         case FMT_MOD_I64:  expected_type = type_int64;     break;
 377
 378                                         default:
 379                                                 warn_invalid_length_modifier(pos, fmt_mod, fmt);
 380                                                 goto next_arg;
 381                                 }
 382                                 allowed_flags = FMT_FLAG_MINUS | FMT_FLAG_SPACE | FMT_FLAG_PLUS | FMT_FLAG_ZERO;
 383                                 break;
 384
 385                         case 'o':
 386                         case 'X':
 387                         case 'x':
 388                                 allowed_flags = FMT_FLAG_MINUS | FMT_FLAG_HASH | FMT_FLAG_ZERO;
 389                                 goto eval_fmt_mod_unsigned;
 390                                 break;
 391
 392                         case 'u':
 393                                 allowed_flags = FMT_FLAG_MINUS | FMT_FLAG_ZERO;
 394 eval_fmt_mod_unsigned:
 395                                 switch (fmt_mod) {
 396                                         case FMT_MOD_NONE: expected_type = type_unsigned_int;       break;
 397                                         case FMT_MOD_hh:   expected_type = type_int;                break; /* TODO promoted unsigned char */
 398                                         case FMT_MOD_h:    expected_type = type_int;                break; /* TODO promoted unsigned short */
 399                                         case FMT_MOD_l:    expected_type = type_unsigned_long;      break;
 400                                         case FMT_MOD_ll:   expected_type = type_unsigned_long_long; break;
 401                                         case FMT_MOD_j:    expected_type = type_uintmax_t;          break;
 402                                         case FMT_MOD_z:    expected_type = type_size_t;             break;
 403                                         case FMT_MOD_t:    expected_type = type_uptrdiff_t;         break;
 404                                         case FMT_MOD_I:    expected_type = type_size_t;             break;
 405                                         case FMT_MOD_I32:  expected_type = type_unsigned_int32;     break;
 406                                         case FMT_MOD_I64:  expected_type = type_unsigned_int64;     break;
 407
 408                                         default:
 409                                                 warn_invalid_length_modifier(pos, fmt_mod, fmt);
 410                                                 goto next_arg;
 411                                 }
 412                                 break;
 413
 414                         case 'A':
 415                         case 'a':
 416                         case 'E':
 417                         case 'e':
 418                         case 'F':
 419                         case 'f':
 420                         case 'G':
 421                         case 'g':
 422                                 switch (fmt_mod) {
 423                                         case FMT_MOD_l:    /* l modifier is ignored */
 424                                         case FMT_MOD_NONE: expected_type = type_double;      break;
 425                                         case FMT_MOD_L:    expected_type = type_long_double; break;
 426
 427                                         default:
 428                                                 warn_invalid_length_modifier(pos, fmt_mod, fmt);
 429                                                 goto next_arg;
 430                                 }
 431                                 allowed_flags = FMT_FLAG_MINUS | FMT_FLAG_SPACE | FMT_FLAG_PLUS | FMT_FLAG_HASH | FMT_FLAG_ZERO;
 432                                 break;
 433
 434                         case 'C':
 435                                 if (fmt_mod != FMT_MOD_NONE) {
 436                                         warn_invalid_length_modifier(pos, fmt_mod, fmt);
 437                                         goto next_arg;
 438                                 }
 439                                 expected_type = type_wchar_t;
 440                                 allowed_flags = FMT_FLAG_NONE;
 441                                 break;
 442
 443                         case 'c':
 444                                 expected_type = type_int;
 445                                 switch (fmt_mod) {
 446                                         case FMT_MOD_NONE: expected_type = type_int;     break; /* TODO promoted char */
 447                                         case FMT_MOD_l:    expected_type = type_wint_t;  break;
 448                                         case FMT_MOD_w:    expected_type = type_wchar_t; break;
 449
 450                                         default:
 451                                                 warn_invalid_length_modifier(pos, fmt_mod, fmt);
 452                                                 goto next_arg;
 453                                 }
 454                                 allowed_flags = FMT_FLAG_NONE;
 455                                 break;
 456
 457                         case 'S':
 458                                 if (fmt_mod != FMT_MOD_NONE) {
 459                                         warn_invalid_length_modifier(pos, fmt_mod, fmt);
 460                                         goto next_arg;
 461                                 }
 462                                 expected_type = type_wchar_t_ptr;
 463                                 expected_qual = TYPE_QUALIFIER_CONST;
 464                                 allowed_flags = FMT_FLAG_NONE;
 465                                 break;
 466
 467                         case 's':
 468                                 switch (fmt_mod) {
 469                                         case FMT_MOD_NONE: expected_type = type_char_ptr;    break;
 470                                         case FMT_MOD_l:    expected_type = type_wchar_t_ptr; break;
 471                                         case FMT_MOD_w:    expected_type = type_wchar_t_ptr; break;
 472
 473                                         default:
 474                                                 warn_invalid_length_modifier(pos, fmt_mod, fmt);
 475                                                 goto next_arg;
 476                                 }
 477                                 expected_qual = TYPE_QUALIFIER_CONST;
 478                                 allowed_flags = FMT_FLAG_NONE;
 479                                 break;
 480
 481                         case 'p':
 482                                 if (fmt_mod != FMT_MOD_NONE) {
 483                                         warn_invalid_length_modifier(pos, fmt_mod, fmt);
 484                                         goto next_arg;
 485                                 }
 486                                 expected_type = type_void_ptr;
 487                                 allowed_flags = FMT_FLAG_NONE;
 488                                 break;
 489
 490                         case 'n':
 491                                 switch (fmt_mod) {
 492                                         case FMT_MOD_NONE: expected_type = type_int_ptr;         break;
 493                                         case FMT_MOD_hh:   expected_type = type_signed_char_ptr; break;
 494                                         case FMT_MOD_h:    expected_type = type_short_ptr;       break;
 495                                         case FMT_MOD_l:    expected_type = type_long_ptr;        break;
 496                                         case FMT_MOD_ll:   expected_type = type_long_long_ptr;   break;
 497                                         case FMT_MOD_j:    expected_type = type_intmax_t_ptr;    break;
 498                                         case FMT_MOD_z:    expected_type = type_ssize_t_ptr;     break;
 499                                         case FMT_MOD_t:    expected_type = type_ptrdiff_t_ptr;   break;
 500
 501                                         default:
 502                                                 warn_invalid_length_modifier(pos, fmt_mod, fmt);
 503                                                 goto next_arg;
 504                                 }
 505                                 allowed_flags = FMT_FLAG_NONE;
 506                                 break;
 507
 508                         default:
 509                                 warningf(pos, "encountered unknown conversion specifier '%%%C'", (wint_t)fmt);
 510                                 goto next_arg;
 511                 }
 512
 513                 if ((fmt_flags & ~allowed_flags) != 0) {
 514                         /* TODO better warning message text */
 515                         warningf(pos, "invalid format flags in conversion specification");
 516                 }
 517
 518                 if (arg == NULL) {
 519                         warningf(pos, "too few arguments for format string");
 520                         return;
 521                 }
 522
 523                 {       /* create a scope here to prevent warning about the jump to next_arg */
 524                         type_t *const arg_type = arg->expression->base.type;
 525                         if (is_type_pointer(expected_type)) {
 526                                 type_t *const arg_skip = skip_typeref(arg_type);
 527                                 if (is_type_pointer(arg_skip)) {
 528                                         type_t *const exp_to = skip_typeref(expected_type->pointer.points_to);
 529                                         type_t *const arg_to = skip_typeref(arg_skip->pointer.points_to);
 530                                         if ((arg_to->base.qualifiers & ~expected_qual) == 0 &&
 531                                                 get_unqualified_type(arg_to) == exp_to) {
 532                                                 goto next_arg;
 533                                         }
 534                                 }
 535                         } else {
 536                                 if (get_unqualified_type(skip_typeref(arg_type)) == expected_type) {
 537                                         goto next_arg;
 538                                 }
 539                         }
 540                         if (is_type_valid(arg_type)) {
 541                                 warningf(pos,
 542                                         "argument type '%T' does not match conversion specifier '%%%s%c'",
 543                                         arg_type, get_length_modifier_name(fmt_mod), (char)fmt);
 544                         }
 545                 }
 546 next_arg:
 547                 arg = arg->next;
 548         }
 549         if (!atend(&vchar)) {
 550                 warningf(pos, "format string contains NUL");
 551         }
 552         if (arg != NULL) {
 553                 warningf(pos, "too many arguments for format string");
 554         }
 555 }
 556
 557 static const struct {
 558         const char    *name;
 559         format_kind_t  fmt_kind;
 560         unsigned       fmt_idx;
 561         unsigned       arg_idx;
 562 } builtin_table[] = {
 563         { "printf",        FORMAT_PRINTF,   0, 1 },
 564         { "wprintf",       FORMAT_PRINTF,   0, 1 },
 565         { "sprintf",       FORMAT_PRINTF,   1, 2 },
 566         { "swprintf",      FORMAT_PRINTF,   1, 2 },
 567         { "snprintf",      FORMAT_PRINTF,   2, 3 },
 568         { "snwprintf",     FORMAT_PRINTF,   2, 3 },
 569         { "fprintf",       FORMAT_PRINTF,   1, 2 },
 570         { "fwprintf",      FORMAT_PRINTF,   1, 2 },
 571         { "snwprintf",     FORMAT_PRINTF,   2, 3 },
 572         { "snwprintf",     FORMAT_PRINTF,   2, 3 },
 573
 574         { "scanf",         FORMAT_SCANF,    0, 1 },
 575         { "wscanf",        FORMAT_SCANF,    0, 1 },
 576         { "sscanf",        FORMAT_SCANF,    1, 2 },
 577         { "swscanf",       FORMAT_SCANF,    1, 2 },
 578         { "fscanf",        FORMAT_SCANF,    1, 2 },
 579         { "fwscanf",       FORMAT_SCANF,    1, 2 },
 580
 581         { "strftime",      FORMAT_STRFTIME, 3, 4 },
 582         { "wcstrftime",    FORMAT_STRFTIME, 3, 4 },
 583
 584         { "strfmon",       FORMAT_STRFMON,  3, 4 },
 585
 586         /* MS extensions */
 587         { "_snprintf",     FORMAT_PRINTF,   2, 3 },
 588         { "_snwprintf",    FORMAT_PRINTF,   2, 3 },
 589         { "_scrintf",      FORMAT_PRINTF,   0, 1 },
 590         { "_scwprintf",    FORMAT_PRINTF,   0, 1 },
 591         { "printf_s",      FORMAT_PRINTF,   0, 1 },
 592         { "wprintf_s",     FORMAT_PRINTF,   0, 1 },
 593         { "sprintf_s",     FORMAT_PRINTF,   3, 4 },
 594         { "swprintf_s",    FORMAT_PRINTF,   3, 4 },
 595         { "fprintf_s",     FORMAT_PRINTF,   1, 2 },
 596         { "fwprintf_s",    FORMAT_PRINTF,   1, 2 },
 597         { "_sprintf_l",    FORMAT_PRINTF,   1, 3 },
 598         { "_swprintf_l",   FORMAT_PRINTF,   1, 3 },
 599         { "_printf_l",     FORMAT_PRINTF,   0, 2 },
 600         { "_wprintf_l",    FORMAT_PRINTF,   0, 2 },
 601         { "_fprintf_l",    FORMAT_PRINTF,   1, 3 },
 602         { "_fwprintf_l",   FORMAT_PRINTF,   1, 3 },
 603         { "_printf_s_l",   FORMAT_PRINTF,   0, 2 },
 604         { "_wprintf_s_l",  FORMAT_PRINTF,   0, 2 },
 605         { "_sprintf_s_l",  FORMAT_PRINTF,   3, 5 },
 606         { "_swprintf_s_l", FORMAT_PRINTF,   3, 5 },
 607         { "_fprintf_s_l",  FORMAT_PRINTF,   1, 3 },
 608         { "_fwprintf_s_l", FORMAT_PRINTF,   1, 3 },
 609 };
 610
 611 void check_format(const call_expression_t *const call)
 612 {
 613         if (!warning.format)
 614                 return;
 615
 616         const expression_t *const func_expr = call->function;
 617         if (func_expr->kind != EXPR_REFERENCE)
 618                 return;
 619
 620         const declaration_t   *const decl = func_expr->reference.declaration;
 621         const call_argument_t *      arg  = call->arguments;
 622
 623         if(false) {
 624                 /* the declaration has a GNU format attribute, check it */
 625         } else {
 626                 /*
 627                  * For some functions we always check the format, even if it was not specified.
 628                  * This allows to check format even in MS mode or without header included.
 629                  */
 630                 const char            *const name = decl->symbol->string;
 631                 for(size_t i = 0; i < sizeof(builtin_table) / sizeof(builtin_table[0]); ++i) {
 632                         if(strcmp(name, builtin_table[i].name) == 0) {
 633                                 if(builtin_table[i].fmt_kind == FORMAT_PRINTF) {
 634                                         check_format_arguments(arg,
 635                                                                builtin_table[i].fmt_idx,
 636                                                                builtin_table[i].arg_idx);
 637                                 }
 638                                 break;
 639                         }
 640                 }
 641         }
 642 }