1 /* Check calls to formatted I/O functions (-Wformat). 2 Copyright (C) 1992-2018 Free Software Foundation, Inc. 3 4 This file is part of GCC. 5 6 GCC is free software; you can redistribute it and/or modify it under 7 the terms of the GNU General Public License as published by the Free 8 Software Foundation; either version 3, or (at your option) any later 9 version. 10 11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY 12 WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with GCC; see the file COPYING3. If not see 18 <http://www.gnu.org/licenses/>. */ 19 20 #ifndef GCC_C_FORMAT_H 21 #define GCC_C_FORMAT_H 22 23 /* The meaningfully distinct length modifiers for format checking recognized 24 by GCC. */ 25 enum format_lengths 26 { 27 FMT_LEN_none, 28 FMT_LEN_hh, 29 FMT_LEN_h, 30 FMT_LEN_l, 31 FMT_LEN_ll, 32 FMT_LEN_L, 33 FMT_LEN_z, 34 FMT_LEN_t, 35 FMT_LEN_j, 36 FMT_LEN_H, 37 FMT_LEN_D, 38 FMT_LEN_DD, 39 FMT_LEN_MAX 40 }; 41 42 43 /* The standard versions in which various format features appeared. */ 44 enum format_std_version 45 { 46 STD_C89, 47 STD_C94, 48 STD_C9L, /* C99, but treat as C89 if -Wno-long-long. */ 49 STD_C99, 50 STD_EXT 51 }; 52 53 /* Flags that may apply to a particular kind of format checked by GCC. */ 54 enum 55 { 56 /* This format converts arguments of types determined by the 57 format string. */ 58 FMT_FLAG_ARG_CONVERT = 1, 59 /* The scanf allocation 'a' kludge applies to this format kind. */ 60 FMT_FLAG_SCANF_A_KLUDGE = 2, 61 /* A % during parsing a specifier is allowed to be a modified % rather 62 that indicating the format is broken and we are out-of-sync. */ 63 FMT_FLAG_FANCY_PERCENT_OK = 4, 64 /* With $ operand numbers, it is OK to reference the same argument more 65 than once. */ 66 FMT_FLAG_DOLLAR_MULTIPLE = 8, 67 /* This format type uses $ operand numbers (strfmon doesn't). */ 68 FMT_FLAG_USE_DOLLAR = 16, 69 /* Zero width is bad in this type of format (scanf). */ 70 FMT_FLAG_ZERO_WIDTH_BAD = 32, 71 /* Empty precision specification is OK in this type of format (printf). */ 72 FMT_FLAG_EMPTY_PREC_OK = 64, 73 /* Gaps are allowed in the arguments with $ operand numbers if all 74 arguments are pointers (scanf). */ 75 FMT_FLAG_DOLLAR_GAP_POINTER_OK = 128, 76 /* The format arg is an opaque object that will be parsed by an external 77 facility. */ 78 FMT_FLAG_PARSE_ARG_CONVERT_EXTERNAL = 256 79 /* Not included here: details of whether width or precision may occur 80 (controlled by width_char and precision_char); details of whether 81 '*' can be used for these (width_type and precision_type); details 82 of whether length modifiers can occur (length_char_specs). */ 83 }; 84 85 /* Structure describing a length modifier supported in format checking, and 86 possibly a doubled version such as "hh". */ 87 struct format_length_info 88 { 89 /* Name of the single-character length modifier. If prefixed by 90 a zero character, it describes a multi character length 91 modifier, like I64, I32, etc. */ 92 const char *name; 93 /* Index into a format_char_info.types array. */ 94 enum format_lengths index; 95 /* Standard version this length appears in. */ 96 enum format_std_version std; 97 /* Same, if the modifier can be repeated, or NULL if it can't. */ 98 const char *double_name; 99 enum format_lengths double_index; 100 enum format_std_version double_std; 101 102 /* If this flag is set, just scalar width identity is checked, and 103 not the type identity itself. */ 104 int scalar_identity_flag; 105 }; 106 107 108 struct kernel_ext_fmt 109 { 110 const char *suffix; 111 112 /* RECORD_TYPE, UNION_TYPE, ENUMERAL_TYPE, or NULL for typedef */ 113 tree_code type_code; 114 int ptrlevel; 115 bool t_const; 116 bool warned; 117 118 const char *type_str; 119 GTY(()) tree type; 120 121 location_t origin_loc; 122 }; 123 124 125 /* Structure describing the combination of a conversion specifier 126 (or a set of specifiers which act identically) and a length modifier. */ 127 struct format_type_detail 128 { 129 /* The standard version this combination of length and type appeared in. 130 This is only relevant if greater than those for length and type 131 individually; otherwise it is ignored. */ 132 enum format_std_version std; 133 /* The name to use for the type, if different from that generated internally 134 (e.g., "signed size_t"). */ 135 const char *name; 136 /* The type itself. */ 137 tree *type; 138 }; 139 140 141 /* Macros to fill out tables of these. */ 142 #define NOARGUMENTS { T89_V, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN } 143 #define BADLEN { STD_C89, NULL, NULL } 144 #define NOLENGTHS { BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN } 145 146 147 /* Structure describing a format conversion specifier (or a set of specifiers 148 which act identically), and the length modifiers used with it. */ 149 struct format_char_info 150 { 151 const char *format_chars; 152 int pointer_count; 153 enum format_std_version std; 154 /* Types accepted for each length modifier. */ 155 format_type_detail types[FMT_LEN_MAX]; 156 /* List of other modifier characters allowed with these specifiers. 157 This lists flags, and additionally "w" for width, "p" for precision 158 (right precision, for strfmon), "#" for left precision (strfmon), 159 "a" for scanf "a" allocation extension (not applicable in C99 mode), 160 "*" for scanf suppression, and "E" and "O" for those strftime 161 modifiers. */ 162 const char *flag_chars; 163 /* List of additional flags describing these conversion specifiers. 164 "c" for generic character pointers being allowed, "2" for strftime 165 two digit year formats, "3" for strftime formats giving two digit 166 years in some locales, "4" for "2" which becomes "3" with an "E" modifier, 167 "o" if use of strftime "O" is a GNU extension beyond C99, 168 "W" if the argument is a pointer which is dereferenced and written into, 169 "R" if the argument is a pointer which is dereferenced and read from, 170 "i" for printf integer formats where the '0' flag is ignored with 171 precision, and "[" for the starting character of a scanf scanset, 172 "<" if the specifier introduces a quoted sequence (such as "%<"), 173 ">" if the specifier terminates a quoted sequence (such as "%>"), 174 "[" if the specifier introduces a color sequence (such as "%r"), 175 "]" if the specifier terminates a color sequence (such as "%R"), 176 "'" (single quote) if the specifier is expected to be quoted when 177 it appears outside a quoted sequence and unquoted otherwise (such 178 as the GCC internal printf format directive "%T"), and 179 "\"" (double quote) if the specifier is not expected to appear in 180 a quoted sequence (such as the GCC internal format directive "%K". */ 181 const char *flags2; 182 /* If this format conversion character consumes more than one argument, 183 CHAIN points to information about the next argument. For later 184 arguments, only POINTER_COUNT, TYPES, and the "c", "R", and "W" flags 185 in FLAGS2 are used. */ 186 const struct format_char_info *chain; 187 188 struct kernel_ext_fmt *kernel_ext; 189 }; 190 191 192 /* Structure describing a flag accepted by some kind of format. */ 193 struct format_flag_spec 194 { 195 /* The flag character in question (0 for end of array). */ 196 int flag_char; 197 /* Zero if this entry describes the flag character in general, or a 198 nonzero character that may be found in flags2 if it describes the 199 flag when used with certain formats only. If the latter, only 200 the first such entry found that applies to the current conversion 201 specifier is used; the values of 'name' and 'long_name' it supplies 202 will be used, if non-NULL and the standard version is higher than 203 the unpredicated one, for any pedantic warning. For example, 'o' 204 for strftime formats (meaning 'O' is an extension over C99). */ 205 int predicate; 206 /* Nonzero if the next character after this flag in the format should 207 be skipped ('=' in strfmon), zero otherwise. */ 208 int skip_next_char; 209 /* True if the flag introduces quoting (as in GCC's %qE). */ 210 bool quoting; 211 /* The name to use for this flag in diagnostic messages. For example, 212 N_("'0' flag"), N_("field width"). */ 213 const char *name; 214 /* Long name for this flag in diagnostic messages; currently only used for 215 "ISO C does not support ...". For example, N_("the 'I' printf flag"). */ 216 const char *long_name; 217 /* The standard version in which it appeared. */ 218 enum format_std_version std; 219 }; 220 221 222 /* Structure describing a combination of flags that is bad for some kind 223 of format. */ 224 struct format_flag_pair 225 { 226 /* The first flag character in question (0 for end of array). */ 227 int flag_char1; 228 /* The second flag character. */ 229 int flag_char2; 230 /* Nonzero if the message should say that the first flag is ignored with 231 the second, zero if the combination should simply be objected to. */ 232 int ignored; 233 /* Zero if this entry applies whenever this flag combination occurs, 234 a nonzero character from flags2 if it only applies in some 235 circumstances (e.g. 'i' for printf formats ignoring 0 with precision). */ 236 int predicate; 237 }; 238 239 240 /* Structure describing a particular kind of format processed by GCC. */ 241 struct format_kind_info 242 { 243 /* The name of this kind of format, for use in diagnostics. Also 244 the name of the attribute (without preceding and following __). */ 245 const char *name; 246 /* Specifications of the length modifiers accepted; possibly NULL. */ 247 const format_length_info *length_char_specs; 248 /* Details of the conversion specification characters accepted. */ 249 const format_char_info *conversion_specs; 250 /* String listing the flag characters that are accepted. */ 251 const char *flag_chars; 252 /* String listing modifier characters (strftime) accepted. May be NULL. */ 253 const char *modifier_chars; 254 /* Details of the flag characters, including pseudo-flags. */ 255 const format_flag_spec *flag_specs; 256 /* Details of bad combinations of flags. */ 257 const format_flag_pair *bad_flag_pairs; 258 /* Flags applicable to this kind of format. */ 259 int flags; 260 /* Flag character to treat a width as, or 0 if width not used. */ 261 int width_char; 262 /* Flag character to treat a left precision (strfmon) as, 263 or 0 if left precision not used. */ 264 int left_precision_char; 265 /* Flag character to treat a precision (for strfmon, right precision) as, 266 or 0 if precision not used. */ 267 int precision_char; 268 /* If a flag character has the effect of suppressing the conversion of 269 an argument ('*' in scanf), that flag character, otherwise 0. */ 270 int suppression_char; 271 /* Flag character to treat a length modifier as (ignored if length 272 modifiers not used). Need not be placed in flag_chars for conversion 273 specifiers, but is used to check for bad combinations such as length 274 modifier with assignment suppression in scanf. */ 275 int length_code_char; 276 /* Assignment-allocation flag character ('m' in scanf), otherwise 0. */ 277 int alloc_char; 278 /* Pointer to type of argument expected if '*' is used for a width, 279 or NULL if '*' not used for widths. */ 280 tree *width_type; 281 /* Pointer to type of argument expected if '*' is used for a precision, 282 or NULL if '*' not used for precisions. */ 283 tree *precision_type; 284 }; 285 286 #define T_I &integer_type_node 287 #define T89_I { STD_C89, NULL, T_I } 288 #define T_L &long_integer_type_node 289 #define T89_L { STD_C89, NULL, T_L } 290 #define T_LL &long_long_integer_type_node 291 #define T9L_LL { STD_C9L, NULL, T_LL } 292 #define TEX_LL { STD_EXT, NULL, T_LL } 293 #define T_U64 &local_uint64_t_node 294 #define TEX_U64 { STD_EXT, "uint64_t", T_U64 } 295 #define T_S64 &local_int64_t_node 296 #define TEX_S64 { STD_EXT, "int64_t", T_S64 } 297 #define T_S &short_integer_type_node 298 #define T89_S { STD_C89, NULL, T_S } 299 #define T_UI &unsigned_type_node 300 #define T89_UI { STD_C89, NULL, T_UI } 301 #define T_UL &long_unsigned_type_node 302 #define T89_UL { STD_C89, NULL, T_UL } 303 #define T_ULL &long_long_unsigned_type_node 304 #define T9L_ULL { STD_C9L, NULL, T_ULL } 305 #define TEX_ULL { STD_EXT, NULL, T_ULL } 306 #define T_US &short_unsigned_type_node 307 #define T89_US { STD_C89, NULL, T_US } 308 #define T_F &float_type_node 309 #define T89_F { STD_C89, NULL, T_F } 310 #define T99_F { STD_C99, NULL, T_F } 311 #define T_D &double_type_node 312 #define T89_D { STD_C89, NULL, T_D } 313 #define T99_D { STD_C99, NULL, T_D } 314 #define T_LD &long_double_type_node 315 #define T89_LD { STD_C89, NULL, T_LD } 316 #define T99_LD { STD_C99, NULL, T_LD } 317 #define T_C &char_type_node 318 #define T89_C { STD_C89, NULL, T_C } 319 #define T_SC &signed_char_type_node 320 #define T99_SC { STD_C99, NULL, T_SC } 321 #define T_UC &unsigned_char_type_node 322 #define T99_UC { STD_C99, NULL, T_UC } 323 #define T_V &void_type_node 324 #define T89_G { STD_C89, NULL, &local_gimple_ptr_node } 325 #define T89_T { STD_C89, NULL, &local_tree_type_node } 326 #define T89_V { STD_C89, NULL, T_V } 327 #define T_W &wchar_type_node 328 #define T94_W { STD_C94, "wchar_t", T_W } 329 #define TEX_W { STD_EXT, "wchar_t", T_W } 330 #define T_WI &wint_type_node 331 #define T94_WI { STD_C94, "wint_t", T_WI } 332 #define TEX_WI { STD_EXT, "wint_t", T_WI } 333 #define T_ST &local_size_t_node 334 #define T99_ST { STD_C99, "size_t", T_ST } 335 #define T_SST &local_ssize_t_node 336 #define T99_SST { STD_C99, "ssize_t", T_SST } 337 #define T_PD &ptrdiff_type_node 338 #define T99_PD { STD_C99, "ptrdiff_t", T_PD } 339 #define T_UPD &unsigned_ptrdiff_type_node 340 #define T99_UPD { STD_C99, "unsigned ptrdiff_t", T_UPD } 341 #define T_IM &intmax_type_node 342 #define T99_IM { STD_C99, "intmax_t", T_IM } 343 #define T_UIM &uintmax_type_node 344 #define T99_UIM { STD_C99, "uintmax_t", T_UIM } 345 #define T_D32 &dfloat32_type_node 346 #define TEX_D32 { STD_EXT, "_Decimal32", T_D32 } 347 #define T_D64 &dfloat64_type_node 348 #define TEX_D64 { STD_EXT, "_Decimal64", T_D64 } 349 #define T_D128 &dfloat128_type_node 350 #define TEX_D128 { STD_EXT, "_Decimal128", T_D128 } 351 352 /* Structure describing how format attributes such as "printf" are 353 interpreted as "gnu_printf" or "ms_printf" on a particular system. 354 TARGET_OVERRIDES_FORMAT_ATTRIBUTES is used to specify target-specific 355 defaults. */ 356 struct target_ovr_attr 357 { 358 /* The name of the to be copied format attribute. */ 359 const char *named_attr_src; 360 /* The name of the to be overridden format attribute. */ 361 const char *named_attr_dst; 362 }; 363 364 #endif /* GCC_C_FORMAT_H */ 365