1/* Check calls to formatted I/O functions (-Wformat).
2   Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3   2001, 2002, 2003, 2004 Free Software Foundation, Inc.
4
5This file is part of GCC.
6
7GCC is free software; you can redistribute it and/or modify it under
8the terms of the GNU General Public License as published by the Free
9Software Foundation; either version 2, or (at your option) any later
10version.
11
12GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13WARRANTY; without even the implied warranty of MERCHANTABILITY or
14FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
15for more details.
16
17You should have received a copy of the GNU General Public License
18along with GCC; see the file COPYING.  If not, write to the Free
19Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
2002110-1301, USA.  */
21
22#ifndef GCC_C_FORMAT_H
23#define GCC_C_FORMAT_H
24
25/* The meaningfully distinct length modifiers for format checking recognized
26   by GCC.  */
27enum format_lengths
28{
29  FMT_LEN_none,
30  FMT_LEN_hh,
31  FMT_LEN_h,
32  FMT_LEN_l,
33  FMT_LEN_ll,
34  FMT_LEN_L,
35  FMT_LEN_z,
36  FMT_LEN_t,
37  FMT_LEN_j,
38  FMT_LEN_MAX
39};
40
41
42/* The standard versions in which various format features appeared.  */
43enum format_std_version
44{
45  STD_C89,
46  STD_C94,
47  STD_C9L, /* C99, but treat as C89 if -Wno-long-long.  */
48  STD_C99,
49  STD_EXT
50};
51
52/* Flags that may apply to a particular kind of format checked by GCC.  */
53enum
54{
55  /* This format converts arguments of types determined by the
56     format string.  */
57  FMT_FLAG_ARG_CONVERT = 1,
58  /* The scanf allocation 'a' kludge applies to this format kind.  */
59  FMT_FLAG_SCANF_A_KLUDGE = 2,
60  /* A % during parsing a specifier is allowed to be a modified % rather
61     that indicating the format is broken and we are out-of-sync.  */
62  FMT_FLAG_FANCY_PERCENT_OK = 4,
63  /* With $ operand numbers, it is OK to reference the same argument more
64     than once.  */
65  FMT_FLAG_DOLLAR_MULTIPLE = 8,
66  /* This format type uses $ operand numbers (strfmon doesn't).  */
67  FMT_FLAG_USE_DOLLAR = 16,
68  /* Zero width is bad in this type of format (scanf).  */
69  FMT_FLAG_ZERO_WIDTH_BAD = 32,
70  /* Empty precision specification is OK in this type of format (printf).  */
71  FMT_FLAG_EMPTY_PREC_OK = 64,
72  /* Gaps are allowed in the arguments with $ operand numbers if all
73     arguments are pointers (scanf).  */
74  FMT_FLAG_DOLLAR_GAP_POINTER_OK = 128
75  /* Not included here: details of whether width or precision may occur
76     (controlled by width_char and precision_char); details of whether
77     '*' can be used for these (width_type and precision_type); details
78     of whether length modifiers can occur (length_char_specs).  */
79};
80
81
82/* Structure describing a length modifier supported in format checking, and
83   possibly a doubled version such as "hh".  */
84typedef struct
85{
86  /* Name of the single-character length modifier.  */
87  const char *name;
88  /* Index into a format_char_info.types array.  */
89  enum format_lengths index;
90  /* Standard version this length appears in.  */
91  enum format_std_version std;
92  /* Same, if the modifier can be repeated, or NULL if it can't.  */
93  const char *double_name;
94  enum format_lengths double_index;
95  enum format_std_version double_std;
96} format_length_info;
97
98
99/* Structure describing the combination of a conversion specifier
100   (or a set of specifiers which act identically) and a length modifier.  */
101typedef struct
102{
103  /* The standard version this combination of length and type appeared in.
104     This is only relevant if greater than those for length and type
105     individually; otherwise it is ignored.  */
106  enum format_std_version std;
107  /* The name to use for the type, if different from that generated internally
108     (e.g., "signed size_t").  */
109  const char *name;
110  /* The type itself.  */
111  tree *type;
112} format_type_detail;
113
114
115/* Macros to fill out tables of these.  */
116#define NOARGUMENTS	{ T89_V, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }
117#define BADLEN	{ 0, NULL, NULL }
118#define NOLENGTHS	{ BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }
119
120
121/* Structure describing a format conversion specifier (or a set of specifiers
122   which act identically), and the length modifiers used with it.  */
123typedef struct format_char_info
124{
125  const char *format_chars;
126  int pointer_count;
127  enum format_std_version std;
128  /* Types accepted for each length modifier.  */
129  format_type_detail types[FMT_LEN_MAX];
130  /* List of other modifier characters allowed with these specifiers.
131     This lists flags, and additionally "w" for width, "p" for precision
132     (right precision, for strfmon), "#" for left precision (strfmon),
133     "a" for scanf "a" allocation extension (not applicable in C99 mode),
134     "*" for scanf suppression, and "E" and "O" for those strftime
135     modifiers.  */
136  const char *flag_chars;
137  /* List of additional flags describing these conversion specifiers.
138     "c" for generic character pointers being allowed, "2" for strftime
139     two digit year formats, "3" for strftime formats giving two digit
140     years in some locales, "4" for "2" which becomes "3" with an "E" modifier,
141     "o" if use of strftime "O" is a GNU extension beyond C99,
142     "W" if the argument is a pointer which is dereferenced and written into,
143     "R" if the argument is a pointer which is dereferenced and read from,
144     "i" for printf integer formats where the '0' flag is ignored with
145     precision, and "[" for the starting character of a scanf scanset.  */
146  const char *flags2;
147  /* If this format conversion character consumes more than one argument,
148     CHAIN points to information about the next argument.  For later
149     arguments, only POINTER_COUNT, TYPES, and the "c", "R", and "W" flags
150     in FLAGS2 are used.  */
151  const struct format_char_info *chain;
152} format_char_info;
153
154
155/* Structure describing a flag accepted by some kind of format.  */
156typedef struct
157{
158  /* The flag character in question (0 for end of array).  */
159  int flag_char;
160  /* Zero if this entry describes the flag character in general, or a
161     nonzero character that may be found in flags2 if it describes the
162     flag when used with certain formats only.  If the latter, only
163     the first such entry found that applies to the current conversion
164     specifier is used; the values of 'name' and 'long_name' it supplies
165     will be used, if non-NULL and the standard version is higher than
166     the unpredicated one, for any pedantic warning.  For example, 'o'
167     for strftime formats (meaning 'O' is an extension over C99).  */
168  int predicate;
169  /* Nonzero if the next character after this flag in the format should
170     be skipped ('=' in strfmon), zero otherwise.  */
171  int skip_next_char;
172  /* The name to use for this flag in diagnostic messages.  For example,
173     N_("'0' flag"), N_("field width").  */
174  const char *name;
175  /* Long name for this flag in diagnostic messages; currently only used for
176     "ISO C does not support ...".  For example, N_("the 'I' printf flag").  */
177  const char *long_name;
178  /* The standard version in which it appeared.  */
179  enum format_std_version std;
180} format_flag_spec;
181
182
183/* Structure describing a combination of flags that is bad for some kind
184   of format.  */
185typedef struct
186{
187  /* The first flag character in question (0 for end of array).  */
188  int flag_char1;
189  /* The second flag character.  */
190  int flag_char2;
191  /* Nonzero if the message should say that the first flag is ignored with
192     the second, zero if the combination should simply be objected to.  */
193  int ignored;
194  /* Zero if this entry applies whenever this flag combination occurs,
195     a nonzero character from flags2 if it only applies in some
196     circumstances (e.g. 'i' for printf formats ignoring 0 with precision).  */
197  int predicate;
198} format_flag_pair;
199
200
201/* Structure describing a particular kind of format processed by GCC.  */
202typedef struct
203{
204  /* The name of this kind of format, for use in diagnostics.  Also
205     the name of the attribute (without preceding and following __).  */
206  const char *name;
207  /* Specifications of the length modifiers accepted; possibly NULL.  */
208  const format_length_info *length_char_specs;
209  /* Details of the conversion specification characters accepted.  */
210  const format_char_info *conversion_specs;
211  /* String listing the flag characters that are accepted.  */
212  const char *flag_chars;
213  /* String listing modifier characters (strftime) accepted.  May be NULL.  */
214  const char *modifier_chars;
215  /* Details of the flag characters, including pseudo-flags.  */
216  const format_flag_spec *flag_specs;
217  /* Details of bad combinations of flags.  */
218  const format_flag_pair *bad_flag_pairs;
219  /* Flags applicable to this kind of format.  */
220  int flags;
221  /* Flag character to treat a width as, or 0 if width not used.  */
222  int width_char;
223  /* Flag character to treat a left precision (strfmon) as,
224     or 0 if left precision not used.  */
225  int left_precision_char;
226  /* Flag character to treat a precision (for strfmon, right precision) as,
227     or 0 if precision not used.  */
228  int precision_char;
229  /* If a flag character has the effect of suppressing the conversion of
230     an argument ('*' in scanf), that flag character, otherwise 0.  */
231  int suppression_char;
232  /* Flag character to treat a length modifier as (ignored if length
233     modifiers not used).  Need not be placed in flag_chars for conversion
234     specifiers, but is used to check for bad combinations such as length
235     modifier with assignment suppression in scanf.  */
236  int length_code_char;
237  /* Pointer to type of argument expected if '*' is used for a width,
238     or NULL if '*' not used for widths.  */
239  tree *width_type;
240  /* Pointer to type of argument expected if '*' is used for a precision,
241     or NULL if '*' not used for precisions.  */
242  tree *precision_type;
243} format_kind_info;
244
245#define T_I	&integer_type_node
246#define T89_I	{ STD_C89, NULL, T_I }
247#define T_L	&long_integer_type_node
248#define T89_L	{ STD_C89, NULL, T_L }
249#define T_LL	&long_long_integer_type_node
250#define T9L_LL	{ STD_C9L, NULL, T_LL }
251#define TEX_LL	{ STD_EXT, NULL, T_LL }
252#define T_S	&short_integer_type_node
253#define T89_S	{ STD_C89, NULL, T_S }
254#define T_UI	&unsigned_type_node
255#define T89_UI	{ STD_C89, NULL, T_UI }
256#define T_UL	&long_unsigned_type_node
257#define T89_UL	{ STD_C89, NULL, T_UL }
258#define T_ULL	&long_long_unsigned_type_node
259#define T9L_ULL	{ STD_C9L, NULL, T_ULL }
260#define TEX_ULL	{ STD_EXT, NULL, T_ULL }
261#define T_US	&short_unsigned_type_node
262#define T89_US	{ STD_C89, NULL, T_US }
263#define T_F	&float_type_node
264#define T89_F	{ STD_C89, NULL, T_F }
265#define T99_F	{ STD_C99, NULL, T_F }
266#define T_D	&double_type_node
267#define T89_D	{ STD_C89, NULL, T_D }
268#define T99_D	{ STD_C99, NULL, T_D }
269#define T_LD	&long_double_type_node
270#define T89_LD	{ STD_C89, NULL, T_LD }
271#define T99_LD	{ STD_C99, NULL, T_LD }
272#define T_C	&char_type_node
273#define T89_C	{ STD_C89, NULL, T_C }
274#define T_SC	&signed_char_type_node
275#define T99_SC	{ STD_C99, NULL, T_SC }
276#define T_UC	&unsigned_char_type_node
277#define T99_UC	{ STD_C99, NULL, T_UC }
278#define T_V	&void_type_node
279#define T89_V	{ STD_C89, NULL, T_V }
280#define T_W	&wchar_type_node
281#define T94_W	{ STD_C94, "wchar_t", T_W }
282#define TEX_W	{ STD_EXT, "wchar_t", T_W }
283#define T_WI	&wint_type_node
284#define T94_WI	{ STD_C94, "wint_t", T_WI }
285#define TEX_WI	{ STD_EXT, "wint_t", T_WI }
286#define T_ST    &size_type_node
287#define T99_ST	{ STD_C99, "size_t", T_ST }
288#define T_SST   &signed_size_type_node
289#define T99_SST	{ STD_C99, "signed size_t", T_SST }
290#define T_PD    &ptrdiff_type_node
291#define T99_PD	{ STD_C99, "ptrdiff_t", T_PD }
292#define T_UPD   &unsigned_ptrdiff_type_node
293#define T99_UPD	{ STD_C99, "unsigned ptrdiff_t", T_UPD }
294#define T_IM    &intmax_type_node
295#define T99_IM	{ STD_C99, "intmax_t", T_IM }
296#define T_UIM   &uintmax_type_node
297#define T99_UIM	{ STD_C99, "uintmax_t", T_UIM }
298
299#endif /* GCC_C_FORMAT_H */
300