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1312c143 JM |
1 | /* Check calls to formatted I/O functions (-Wformat). |
2 | Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001 | |
3 | Free Software Foundation, Inc. | |
4 | ||
1322177d | 5 | This file is part of GCC. |
1312c143 | 6 | |
1322177d LB |
7 | GCC is free software; you can redistribute it and/or modify it under |
8 | the terms of the GNU General Public License as published by the Free | |
9 | Software Foundation; either version 2, or (at your option) any later | |
10 | version. | |
1312c143 | 11 | |
1322177d LB |
12 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
13 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
14 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
15 | for more details. | |
1312c143 JM |
16 | |
17 | You should have received a copy of the GNU General Public License | |
1322177d LB |
18 | along with GCC; see the file COPYING. If not, write to the Free |
19 | Software Foundation, 59 Temple Place - Suite 330, Boston, MA | |
20 | 02111-1307, USA. */ | |
1312c143 JM |
21 | |
22 | #include "config.h" | |
23 | #include "system.h" | |
24 | #include "tree.h" | |
25 | #include "flags.h" | |
26 | #include "toplev.h" | |
27 | #include "c-common.h" | |
28 | #include "intl.h" | |
29 | #include "diagnostic.h" | |
30 | ||
31 | \f | |
32 | /* Command line options and their associated flags. */ | |
33 | ||
34 | /* Warn about format/argument anomalies in calls to formatted I/O functions | |
35 | (*printf, *scanf, strftime, strfmon, etc.). */ | |
36 | ||
37 | int warn_format; | |
38 | ||
39 | /* Warn about Y2K problems with strftime formats. */ | |
40 | ||
41 | int warn_format_y2k; | |
42 | ||
43 | /* Warn about excess arguments to formats. */ | |
44 | ||
45 | int warn_format_extra_args; | |
46 | ||
47 | /* Warn about non-literal format arguments. */ | |
48 | ||
49 | int warn_format_nonliteral; | |
50 | ||
51 | /* Warn about possible security problems with calls to format functions. */ | |
52 | ||
53 | int warn_format_security; | |
54 | ||
55 | /* Set format warning options according to a -Wformat=n option. */ | |
56 | ||
57 | void | |
58 | set_Wformat (setting) | |
59 | int setting; | |
60 | { | |
61 | warn_format = setting; | |
62 | warn_format_y2k = setting; | |
63 | warn_format_extra_args = setting; | |
64 | if (setting != 1) | |
65 | { | |
66 | warn_format_nonliteral = setting; | |
67 | warn_format_security = setting; | |
68 | } | |
69 | } | |
70 | ||
71 | \f | |
72 | /* Handle attributes associated with format checking. */ | |
73 | ||
74 | /* This must be in the same order as format_types, with format_type_error | |
75 | last. */ | |
76 | enum format_type { printf_format_type, scanf_format_type, | |
77 | strftime_format_type, strfmon_format_type, | |
78 | format_type_error }; | |
79 | ||
80 | static enum format_type decode_format_type PARAMS ((const char *)); | |
81 | static void record_function_format PARAMS ((tree, tree, enum format_type, | |
82 | int, int)); | |
83 | static void record_international_format PARAMS ((tree, tree, int)); | |
84 | ||
85 | /* Handle the format attribute (with arguments ARGS) attached to the decl | |
86 | DECL. It is already verified that DECL is a decl and ARGS contains | |
87 | exactly three arguments. */ | |
88 | ||
89 | void | |
90 | decl_handle_format_attribute (decl, args) | |
91 | tree decl, args; | |
92 | { | |
93 | tree type = TREE_TYPE (decl); | |
94 | tree format_type_id = TREE_VALUE (args); | |
95 | tree format_num_expr = TREE_VALUE (TREE_CHAIN (args)); | |
96 | tree first_arg_num_expr | |
97 | = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (args))); | |
98 | unsigned HOST_WIDE_INT format_num, first_arg_num; | |
99 | enum format_type format_type; | |
100 | tree argument; | |
101 | unsigned int arg_num; | |
102 | ||
103 | if (TREE_CODE (decl) != FUNCTION_DECL) | |
104 | { | |
105 | error_with_decl (decl, | |
106 | "argument format specified for non-function `%s'"); | |
107 | return; | |
108 | } | |
109 | ||
110 | if (TREE_CODE (format_type_id) != IDENTIFIER_NODE) | |
111 | { | |
112 | error ("unrecognized format specifier"); | |
113 | return; | |
114 | } | |
115 | else | |
116 | { | |
117 | const char *p = IDENTIFIER_POINTER (format_type_id); | |
118 | ||
119 | format_type = decode_format_type (p); | |
120 | ||
121 | if (format_type == format_type_error) | |
122 | { | |
123 | warning ("`%s' is an unrecognized format function type", p); | |
124 | return; | |
125 | } | |
126 | } | |
127 | ||
128 | /* Strip any conversions from the string index and first arg number | |
129 | and verify they are constants. */ | |
130 | while (TREE_CODE (format_num_expr) == NOP_EXPR | |
131 | || TREE_CODE (format_num_expr) == CONVERT_EXPR | |
132 | || TREE_CODE (format_num_expr) == NON_LVALUE_EXPR) | |
133 | format_num_expr = TREE_OPERAND (format_num_expr, 0); | |
134 | ||
135 | while (TREE_CODE (first_arg_num_expr) == NOP_EXPR | |
136 | || TREE_CODE (first_arg_num_expr) == CONVERT_EXPR | |
137 | || TREE_CODE (first_arg_num_expr) == NON_LVALUE_EXPR) | |
138 | first_arg_num_expr = TREE_OPERAND (first_arg_num_expr, 0); | |
139 | ||
140 | if (TREE_CODE (format_num_expr) != INTEGER_CST | |
141 | || TREE_INT_CST_HIGH (format_num_expr) != 0 | |
142 | || TREE_CODE (first_arg_num_expr) != INTEGER_CST | |
143 | || TREE_INT_CST_HIGH (first_arg_num_expr) != 0) | |
144 | { | |
145 | error ("format string has invalid operand number"); | |
146 | return; | |
147 | } | |
148 | ||
149 | format_num = TREE_INT_CST_LOW (format_num_expr); | |
150 | first_arg_num = TREE_INT_CST_LOW (first_arg_num_expr); | |
151 | if (first_arg_num != 0 && first_arg_num <= format_num) | |
152 | { | |
153 | error ("format string arg follows the args to be formatted"); | |
154 | return; | |
155 | } | |
156 | ||
157 | /* If a parameter list is specified, verify that the format_num | |
158 | argument is actually a string, in case the format attribute | |
159 | is in error. */ | |
160 | argument = TYPE_ARG_TYPES (type); | |
161 | if (argument) | |
162 | { | |
163 | for (arg_num = 1; argument != 0 && arg_num != format_num; | |
164 | ++arg_num, argument = TREE_CHAIN (argument)) | |
165 | ; | |
166 | ||
167 | if (! argument | |
168 | || TREE_CODE (TREE_VALUE (argument)) != POINTER_TYPE | |
169 | || (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_VALUE (argument))) | |
170 | != char_type_node)) | |
171 | { | |
172 | error ("format string arg not a string type"); | |
173 | return; | |
174 | } | |
175 | ||
176 | else if (first_arg_num != 0) | |
177 | { | |
178 | /* Verify that first_arg_num points to the last arg, | |
179 | the ... */ | |
180 | while (argument) | |
181 | arg_num++, argument = TREE_CHAIN (argument); | |
182 | ||
183 | if (arg_num != first_arg_num) | |
184 | { | |
185 | error ("args to be formatted is not '...'"); | |
186 | return; | |
187 | } | |
188 | } | |
189 | } | |
190 | ||
191 | if (format_type == strftime_format_type && first_arg_num != 0) | |
192 | { | |
193 | error ("strftime formats cannot format arguments"); | |
194 | return; | |
195 | } | |
196 | ||
197 | record_function_format (DECL_NAME (decl), DECL_ASSEMBLER_NAME (decl), | |
198 | format_type, format_num, first_arg_num); | |
199 | } | |
200 | ||
201 | ||
202 | /* Handle the format_arg attribute (with arguments ARGS) attached to | |
203 | the decl DECL. It is already verified that DECL is a decl and | |
204 | ARGS contains exactly one argument. */ | |
205 | ||
206 | void | |
207 | decl_handle_format_arg_attribute (decl, args) | |
208 | tree decl, args; | |
209 | { | |
210 | tree type = TREE_TYPE (decl); | |
211 | tree format_num_expr = TREE_VALUE (args); | |
212 | unsigned HOST_WIDE_INT format_num; | |
213 | unsigned int arg_num; | |
214 | tree argument; | |
215 | ||
216 | if (TREE_CODE (decl) != FUNCTION_DECL) | |
217 | { | |
218 | error_with_decl (decl, | |
219 | "argument format specified for non-function `%s'"); | |
220 | return; | |
221 | } | |
222 | ||
223 | /* Strip any conversions from the first arg number and verify it | |
224 | is a constant. */ | |
225 | while (TREE_CODE (format_num_expr) == NOP_EXPR | |
226 | || TREE_CODE (format_num_expr) == CONVERT_EXPR | |
227 | || TREE_CODE (format_num_expr) == NON_LVALUE_EXPR) | |
228 | format_num_expr = TREE_OPERAND (format_num_expr, 0); | |
229 | ||
230 | if (TREE_CODE (format_num_expr) != INTEGER_CST | |
231 | || TREE_INT_CST_HIGH (format_num_expr) != 0) | |
232 | { | |
233 | error ("format string has invalid operand number"); | |
234 | return; | |
235 | } | |
236 | ||
237 | format_num = TREE_INT_CST_LOW (format_num_expr); | |
238 | ||
239 | /* If a parameter list is specified, verify that the format_num | |
240 | argument is actually a string, in case the format attribute | |
241 | is in error. */ | |
242 | argument = TYPE_ARG_TYPES (type); | |
243 | if (argument) | |
244 | { | |
245 | for (arg_num = 1; argument != 0 && arg_num != format_num; | |
246 | ++arg_num, argument = TREE_CHAIN (argument)) | |
247 | ; | |
248 | ||
249 | if (! argument | |
250 | || TREE_CODE (TREE_VALUE (argument)) != POINTER_TYPE | |
251 | || (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_VALUE (argument))) | |
252 | != char_type_node)) | |
253 | { | |
254 | error ("format string arg not a string type"); | |
255 | return; | |
256 | } | |
257 | } | |
258 | ||
259 | if (TREE_CODE (TREE_TYPE (TREE_TYPE (decl))) != POINTER_TYPE | |
260 | || (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (TREE_TYPE (decl)))) | |
261 | != char_type_node)) | |
262 | { | |
263 | error ("function does not return string type"); | |
264 | return; | |
265 | } | |
266 | ||
267 | record_international_format (DECL_NAME (decl), DECL_ASSEMBLER_NAME (decl), | |
268 | format_num); | |
269 | } | |
270 | ||
271 | typedef struct function_format_info | |
272 | { | |
273 | struct function_format_info *next; /* next structure on the list */ | |
274 | tree name; /* identifier such as "printf" */ | |
275 | tree assembler_name; /* optional mangled identifier (for C++) */ | |
276 | enum format_type format_type; /* type of format (printf, scanf, etc.) */ | |
277 | int format_num; /* number of format argument */ | |
278 | int first_arg_num; /* number of first arg (zero for varargs) */ | |
279 | } function_format_info; | |
280 | ||
281 | static function_format_info *function_format_list = NULL; | |
282 | ||
283 | typedef struct international_format_info | |
284 | { | |
285 | struct international_format_info *next; /* next structure on the list */ | |
286 | tree name; /* identifier such as "gettext" */ | |
287 | tree assembler_name; /* optional mangled identifier (for C++) */ | |
288 | int format_num; /* number of format argument */ | |
289 | } international_format_info; | |
290 | ||
291 | static international_format_info *international_format_list = NULL; | |
292 | ||
293 | /* Initialize the table of functions to perform format checking on. | |
294 | The ISO C functions are always checked (whether <stdio.h> is | |
295 | included or not), since it is common to call printf without | |
296 | including <stdio.h>. There shouldn't be a problem with this, | |
297 | since ISO C reserves these function names whether you include the | |
298 | header file or not. In any case, the checking is harmless. With | |
299 | -ffreestanding, these default attributes are disabled, and must be | |
300 | specified manually if desired. | |
301 | ||
302 | Also initialize the name of function that modify the format string for | |
303 | internationalization purposes. */ | |
304 | ||
305 | void | |
306 | init_function_format_info () | |
307 | { | |
308 | if (flag_hosted) | |
309 | { | |
310 | /* Functions from ISO/IEC 9899:1990. */ | |
311 | record_function_format (get_identifier ("printf"), NULL_TREE, | |
312 | printf_format_type, 1, 2); | |
313 | record_function_format (get_identifier ("__builtin_printf"), NULL_TREE, | |
314 | printf_format_type, 1, 2); | |
315 | record_function_format (get_identifier ("fprintf"), NULL_TREE, | |
316 | printf_format_type, 2, 3); | |
317 | record_function_format (get_identifier ("__builtin_fprintf"), NULL_TREE, | |
318 | printf_format_type, 2, 3); | |
319 | record_function_format (get_identifier ("sprintf"), NULL_TREE, | |
320 | printf_format_type, 2, 3); | |
321 | record_function_format (get_identifier ("scanf"), NULL_TREE, | |
322 | scanf_format_type, 1, 2); | |
323 | record_function_format (get_identifier ("fscanf"), NULL_TREE, | |
324 | scanf_format_type, 2, 3); | |
325 | record_function_format (get_identifier ("sscanf"), NULL_TREE, | |
326 | scanf_format_type, 2, 3); | |
327 | record_function_format (get_identifier ("vprintf"), NULL_TREE, | |
328 | printf_format_type, 1, 0); | |
329 | record_function_format (get_identifier ("vfprintf"), NULL_TREE, | |
330 | printf_format_type, 2, 0); | |
331 | record_function_format (get_identifier ("vsprintf"), NULL_TREE, | |
332 | printf_format_type, 2, 0); | |
333 | record_function_format (get_identifier ("strftime"), NULL_TREE, | |
334 | strftime_format_type, 3, 0); | |
335 | } | |
336 | ||
337 | if (flag_hosted && flag_isoc99) | |
338 | { | |
339 | /* ISO C99 adds the snprintf and vscanf family functions. */ | |
340 | record_function_format (get_identifier ("snprintf"), NULL_TREE, | |
341 | printf_format_type, 3, 4); | |
342 | record_function_format (get_identifier ("vsnprintf"), NULL_TREE, | |
343 | printf_format_type, 3, 0); | |
344 | record_function_format (get_identifier ("vscanf"), NULL_TREE, | |
345 | scanf_format_type, 1, 0); | |
346 | record_function_format (get_identifier ("vfscanf"), NULL_TREE, | |
347 | scanf_format_type, 2, 0); | |
348 | record_function_format (get_identifier ("vsscanf"), NULL_TREE, | |
349 | scanf_format_type, 2, 0); | |
350 | } | |
351 | ||
352 | if (flag_hosted && flag_noniso_default_format_attributes) | |
353 | { | |
354 | /* Uniforum/GNU gettext functions, not in ISO C. */ | |
355 | record_international_format (get_identifier ("gettext"), NULL_TREE, 1); | |
356 | record_international_format (get_identifier ("dgettext"), NULL_TREE, 2); | |
357 | record_international_format (get_identifier ("dcgettext"), NULL_TREE, 2); | |
358 | /* X/Open strfmon function. */ | |
359 | record_function_format (get_identifier ("strfmon"), NULL_TREE, | |
360 | strfmon_format_type, 3, 4); | |
361 | } | |
362 | } | |
363 | ||
364 | /* Record information for argument format checking. FUNCTION_IDENT is | |
365 | the identifier node for the name of the function to check (its decl | |
366 | need not exist yet). | |
367 | FORMAT_TYPE specifies the type of format checking. FORMAT_NUM is the number | |
368 | of the argument which is the format control string (starting from 1). | |
369 | FIRST_ARG_NUM is the number of the first actual argument to check | |
370 | against the format string, or zero if no checking is not be done | |
371 | (e.g. for varargs such as vfprintf). */ | |
372 | ||
373 | static void | |
374 | record_function_format (name, assembler_name, format_type, | |
375 | format_num, first_arg_num) | |
376 | tree name; | |
377 | tree assembler_name; | |
378 | enum format_type format_type; | |
379 | int format_num; | |
380 | int first_arg_num; | |
381 | { | |
382 | function_format_info *info; | |
383 | ||
384 | /* Re-use existing structure if it's there. */ | |
385 | ||
386 | for (info = function_format_list; info; info = info->next) | |
387 | { | |
388 | if (info->name == name && info->assembler_name == assembler_name) | |
389 | break; | |
390 | } | |
391 | if (! info) | |
392 | { | |
393 | info = (function_format_info *) xmalloc (sizeof (function_format_info)); | |
394 | info->next = function_format_list; | |
395 | function_format_list = info; | |
396 | ||
397 | info->name = name; | |
398 | info->assembler_name = assembler_name; | |
399 | } | |
400 | ||
401 | info->format_type = format_type; | |
402 | info->format_num = format_num; | |
403 | info->first_arg_num = first_arg_num; | |
404 | } | |
405 | ||
406 | /* Record information for the names of function that modify the format | |
407 | argument to format functions. FUNCTION_IDENT is the identifier node for | |
408 | the name of the function (its decl need not exist yet) and FORMAT_NUM is | |
409 | the number of the argument which is the format control string (starting | |
410 | from 1). */ | |
411 | ||
412 | static void | |
413 | record_international_format (name, assembler_name, format_num) | |
414 | tree name; | |
415 | tree assembler_name; | |
416 | int format_num; | |
417 | { | |
418 | international_format_info *info; | |
419 | ||
420 | /* Re-use existing structure if it's there. */ | |
421 | ||
422 | for (info = international_format_list; info; info = info->next) | |
423 | { | |
424 | if (info->name == name && info->assembler_name == assembler_name) | |
425 | break; | |
426 | } | |
427 | ||
428 | if (! info) | |
429 | { | |
430 | info | |
431 | = (international_format_info *) | |
432 | xmalloc (sizeof (international_format_info)); | |
433 | info->next = international_format_list; | |
434 | international_format_list = info; | |
435 | ||
436 | info->name = name; | |
437 | info->assembler_name = assembler_name; | |
438 | } | |
439 | ||
440 | info->format_num = format_num; | |
441 | } | |
442 | ||
443 | ||
444 | ||
445 | \f | |
446 | /* Check a call to a format function against a parameter list. */ | |
447 | ||
448 | /* The meaningfully distinct length modifiers for format checking recognised | |
449 | by GCC. */ | |
450 | enum format_lengths | |
451 | { | |
452 | FMT_LEN_none, | |
453 | FMT_LEN_hh, | |
454 | FMT_LEN_h, | |
455 | FMT_LEN_l, | |
456 | FMT_LEN_ll, | |
457 | FMT_LEN_L, | |
458 | FMT_LEN_z, | |
459 | FMT_LEN_t, | |
460 | FMT_LEN_j, | |
461 | FMT_LEN_MAX | |
462 | }; | |
463 | ||
464 | ||
465 | /* The standard versions in which various format features appeared. */ | |
466 | enum format_std_version | |
467 | { | |
468 | STD_C89, | |
469 | STD_C94, | |
470 | STD_C9L, /* C99, but treat as C89 if -Wno-long-long. */ | |
471 | STD_C99, | |
472 | STD_EXT | |
473 | }; | |
474 | ||
475 | /* The C standard version C++ is treated as equivalent to | |
476 | or inheriting from, for the purpose of format features supported. */ | |
477 | #define CPLUSPLUS_STD_VER STD_C89 | |
478 | /* The C standard version we are checking formats against when pedantic. */ | |
dbbbbf3b | 479 | #define C_STD_VER ((int)(c_language == clk_cplusplus \ |
1312c143 JM |
480 | ? CPLUSPLUS_STD_VER \ |
481 | : (flag_isoc99 \ | |
482 | ? STD_C99 \ | |
dbbbbf3b | 483 | : (flag_isoc94 ? STD_C94 : STD_C89)))) |
1312c143 JM |
484 | /* The name to give to the standard version we are warning about when |
485 | pedantic. FEATURE_VER is the version in which the feature warned out | |
486 | appeared, which is higher than C_STD_VER. */ | |
487 | #define C_STD_NAME(FEATURE_VER) (c_language == clk_cplusplus \ | |
488 | ? "ISO C++" \ | |
489 | : ((FEATURE_VER) == STD_EXT \ | |
490 | ? "ISO C" \ | |
491 | : "ISO C89")) | |
492 | /* Adjust a C standard version, which may be STD_C9L, to account for | |
493 | -Wno-long-long. Returns other standard versions unchanged. */ | |
494 | #define ADJ_STD(VER) ((int)((VER) == STD_C9L \ | |
495 | ? (warn_long_long ? STD_C99 : STD_C89) \ | |
496 | : (VER))) | |
497 | ||
498 | /* Flags that may apply to a particular kind of format checked by GCC. */ | |
499 | enum | |
500 | { | |
501 | /* This format converts arguments of types determined by the | |
502 | format string. */ | |
503 | FMT_FLAG_ARG_CONVERT = 1, | |
504 | /* The scanf allocation 'a' kludge applies to this format kind. */ | |
505 | FMT_FLAG_SCANF_A_KLUDGE = 2, | |
506 | /* A % during parsing a specifier is allowed to be a modified % rather | |
507 | that indicating the format is broken and we are out-of-sync. */ | |
508 | FMT_FLAG_FANCY_PERCENT_OK = 4, | |
509 | /* With $ operand numbers, it is OK to reference the same argument more | |
510 | than once. */ | |
511 | FMT_FLAG_DOLLAR_MULTIPLE = 8, | |
512 | /* This format type uses $ operand numbers (strfmon doesn't). */ | |
513 | FMT_FLAG_USE_DOLLAR = 16, | |
514 | /* Zero width is bad in this type of format (scanf). */ | |
515 | FMT_FLAG_ZERO_WIDTH_BAD = 32, | |
516 | /* Empty precision specification is OK in this type of format (printf). */ | |
517 | FMT_FLAG_EMPTY_PREC_OK = 64 | |
518 | /* Not included here: details of whether width or precision may occur | |
519 | (controlled by width_char and precision_char); details of whether | |
520 | '*' can be used for these (width_type and precision_type); details | |
521 | of whether length modifiers can occur (length_char_specs). */ | |
522 | }; | |
523 | ||
524 | ||
525 | /* Structure describing a length modifier supported in format checking, and | |
526 | possibly a doubled version such as "hh". */ | |
527 | typedef struct | |
528 | { | |
529 | /* Name of the single-character length modifier. */ | |
530 | const char *name; | |
531 | /* Index into a format_char_info.types array. */ | |
532 | enum format_lengths index; | |
533 | /* Standard version this length appears in. */ | |
534 | enum format_std_version std; | |
535 | /* Same, if the modifier can be repeated, or NULL if it can't. */ | |
536 | const char *double_name; | |
537 | enum format_lengths double_index; | |
538 | enum format_std_version double_std; | |
539 | } format_length_info; | |
540 | ||
541 | ||
542 | /* Structure desribing the combination of a conversion specifier | |
543 | (or a set of specifiers which act identically) and a length modifier. */ | |
544 | typedef struct | |
545 | { | |
546 | /* The standard version this combination of length and type appeared in. | |
547 | This is only relevant if greater than those for length and type | |
548 | individually; otherwise it is ignored. */ | |
549 | enum format_std_version std; | |
550 | /* The name to use for the type, if different from that generated internally | |
551 | (e.g., "signed size_t"). */ | |
552 | const char *name; | |
553 | /* The type itself. */ | |
554 | tree *type; | |
555 | } format_type_detail; | |
556 | ||
557 | ||
558 | /* Macros to fill out tables of these. */ | |
559 | #define BADLEN { 0, NULL, NULL } | |
560 | #define NOLENGTHS { BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN } | |
561 | ||
562 | ||
563 | /* Structure desribing a format conversion specifier (or a set of specifiers | |
564 | which act identically), and the length modifiers used with it. */ | |
565 | typedef struct | |
566 | { | |
567 | const char *format_chars; | |
568 | int pointer_count; | |
569 | enum format_std_version std; | |
570 | /* Types accepted for each length modifier. */ | |
571 | format_type_detail types[FMT_LEN_MAX]; | |
572 | /* List of other modifier characters allowed with these specifiers. | |
573 | This lists flags, and additionally "w" for width, "p" for precision | |
574 | (right precision, for strfmon), "#" for left precision (strfmon), | |
575 | "a" for scanf "a" allocation extension (not applicable in C99 mode), | |
576 | "*" for scanf suppression, and "E" and "O" for those strftime | |
577 | modifiers. */ | |
578 | const char *flag_chars; | |
579 | /* List of additional flags describing these conversion specifiers. | |
580 | "c" for generic character pointers being allowed, "2" for strftime | |
581 | two digit year formats, "3" for strftime formats giving two digit | |
582 | years in some locales, "4" for "2" which becomes "3" with an "E" modifier, | |
583 | "o" if use of strftime "O" is a GNU extension beyond C99, | |
584 | "W" if the argument is a pointer which is dereferenced and written into, | |
585 | "R" if the argument is a pointer which is dereferenced and read from, | |
586 | "i" for printf integer formats where the '0' flag is ignored with | |
587 | precision, and "[" for the starting character of a scanf scanset. */ | |
588 | const char *flags2; | |
589 | } format_char_info; | |
590 | ||
591 | ||
592 | /* Structure describing a flag accepted by some kind of format. */ | |
593 | typedef struct | |
594 | { | |
595 | /* The flag character in question (0 for end of array). */ | |
596 | int flag_char; | |
597 | /* Zero if this entry describes the flag character in general, or a | |
598 | non-zero character that may be found in flags2 if it describes the | |
599 | flag when used with certain formats only. If the latter, only | |
600 | the first such entry found that applies to the current conversion | |
601 | specifier is used; the values of `name' and `long_name' it supplies | |
602 | will be used, if non-NULL and the standard version is higher than | |
603 | the unpredicated one, for any pedantic warning. For example, 'o' | |
604 | for strftime formats (meaning 'O' is an extension over C99). */ | |
605 | int predicate; | |
606 | /* Nonzero if the next character after this flag in the format should | |
607 | be skipped ('=' in strfmon), zero otherwise. */ | |
608 | int skip_next_char; | |
609 | /* The name to use for this flag in diagnostic messages. For example, | |
610 | N_("`0' flag"), N_("field width"). */ | |
611 | const char *name; | |
612 | /* Long name for this flag in diagnostic messages; currently only used for | |
613 | "ISO C does not support ...". For example, N_("the `I' printf flag"). */ | |
614 | const char *long_name; | |
615 | /* The standard version in which it appeared. */ | |
616 | enum format_std_version std; | |
617 | } format_flag_spec; | |
618 | ||
619 | ||
620 | /* Structure describing a combination of flags that is bad for some kind | |
621 | of format. */ | |
622 | typedef struct | |
623 | { | |
624 | /* The first flag character in question (0 for end of array). */ | |
625 | int flag_char1; | |
626 | /* The second flag character. */ | |
627 | int flag_char2; | |
628 | /* Non-zero if the message should say that the first flag is ignored with | |
629 | the second, zero if the combination should simply be objected to. */ | |
630 | int ignored; | |
631 | /* Zero if this entry applies whenever this flag combination occurs, | |
632 | a non-zero character from flags2 if it only applies in some | |
633 | circumstances (e.g. 'i' for printf formats ignoring 0 with precision). */ | |
634 | int predicate; | |
635 | } format_flag_pair; | |
636 | ||
637 | ||
638 | /* Structure describing a particular kind of format processed by GCC. */ | |
639 | typedef struct | |
640 | { | |
641 | /* The name of this kind of format, for use in diagnostics. Also | |
642 | the name of the attribute (without preceding and following __). */ | |
643 | const char *name; | |
644 | /* Specifications of the length modifiers accepted; possibly NULL. */ | |
645 | const format_length_info *length_char_specs; | |
646 | /* Details of the conversion specification characters accepted. */ | |
647 | const format_char_info *conversion_specs; | |
648 | /* String listing the flag characters that are accepted. */ | |
649 | const char *flag_chars; | |
650 | /* String listing modifier characters (strftime) accepted. May be NULL. */ | |
651 | const char *modifier_chars; | |
652 | /* Details of the flag characters, including pseudo-flags. */ | |
653 | const format_flag_spec *flag_specs; | |
654 | /* Details of bad combinations of flags. */ | |
655 | const format_flag_pair *bad_flag_pairs; | |
656 | /* Flags applicable to this kind of format. */ | |
657 | int flags; | |
658 | /* Flag character to treat a width as, or 0 if width not used. */ | |
659 | int width_char; | |
660 | /* Flag character to treat a left precision (strfmon) as, | |
661 | or 0 if left precision not used. */ | |
662 | int left_precision_char; | |
663 | /* Flag character to treat a precision (for strfmon, right precision) as, | |
664 | or 0 if precision not used. */ | |
665 | int precision_char; | |
666 | /* If a flag character has the effect of suppressing the conversion of | |
667 | an argument ('*' in scanf), that flag character, otherwise 0. */ | |
668 | int suppression_char; | |
669 | /* Flag character to treat a length modifier as (ignored if length | |
670 | modifiers not used). Need not be placed in flag_chars for conversion | |
671 | specifiers, but is used to check for bad combinations such as length | |
672 | modifier with assignment suppression in scanf. */ | |
673 | int length_code_char; | |
674 | /* Pointer to type of argument expected if '*' is used for a width, | |
675 | or NULL if '*' not used for widths. */ | |
676 | tree *width_type; | |
677 | /* Pointer to type of argument expected if '*' is used for a precision, | |
678 | or NULL if '*' not used for precisions. */ | |
679 | tree *precision_type; | |
680 | } format_kind_info; | |
681 | ||
682 | ||
683 | /* Structure describing details of a type expected in format checking, | |
684 | and the type to check against it. */ | |
685 | typedef struct format_wanted_type | |
686 | { | |
687 | /* The type wanted. */ | |
688 | tree wanted_type; | |
689 | /* The name of this type to use in diagnostics. */ | |
690 | const char *wanted_type_name; | |
691 | /* The level of indirection through pointers at which this type occurs. */ | |
692 | int pointer_count; | |
693 | /* Whether, when pointer_count is 1, to allow any character type when | |
694 | pedantic, rather than just the character or void type specified. */ | |
695 | int char_lenient_flag; | |
696 | /* Whether the argument, dereferenced once, is written into and so the | |
697 | argument must not be a pointer to a const-qualified type. */ | |
698 | int writing_in_flag; | |
699 | /* Whether the argument, dereferenced once, is read from and so | |
700 | must not be a NULL pointer. */ | |
701 | int reading_from_flag; | |
702 | /* If warnings should be of the form "field precision is not type int", | |
703 | the name to use (in this case "field precision"), otherwise NULL, | |
704 | for "%s format, %s arg" type messages. If (in an extension), this | |
705 | is a pointer type, wanted_type_name should be set to include the | |
706 | terminating '*' characters of the type name to give a correct | |
707 | message. */ | |
708 | const char *name; | |
709 | /* The actual parameter to check against the wanted type. */ | |
710 | tree param; | |
711 | /* The argument number of that parameter. */ | |
712 | int arg_num; | |
713 | /* The next type to check for this format conversion, or NULL if none. */ | |
714 | struct format_wanted_type *next; | |
715 | } format_wanted_type; | |
716 | ||
717 | ||
718 | static const format_length_info printf_length_specs[] = | |
719 | { | |
720 | { "h", FMT_LEN_h, STD_C89, "hh", FMT_LEN_hh, STD_C99 }, | |
721 | { "l", FMT_LEN_l, STD_C89, "ll", FMT_LEN_ll, STD_C9L }, | |
722 | { "q", FMT_LEN_ll, STD_EXT, NULL, 0, 0 }, | |
723 | { "L", FMT_LEN_L, STD_C89, NULL, 0, 0 }, | |
724 | { "z", FMT_LEN_z, STD_C99, NULL, 0, 0 }, | |
725 | { "Z", FMT_LEN_z, STD_EXT, NULL, 0, 0 }, | |
726 | { "t", FMT_LEN_t, STD_C99, NULL, 0, 0 }, | |
727 | { "j", FMT_LEN_j, STD_C99, NULL, 0, 0 }, | |
728 | { NULL, 0, 0, NULL, 0, 0 } | |
729 | }; | |
730 | ||
731 | ||
732 | /* This differs from printf_length_specs only in that "Z" is not accepted. */ | |
733 | static const format_length_info scanf_length_specs[] = | |
734 | { | |
735 | { "h", FMT_LEN_h, STD_C89, "hh", FMT_LEN_hh, STD_C99 }, | |
736 | { "l", FMT_LEN_l, STD_C89, "ll", FMT_LEN_ll, STD_C9L }, | |
737 | { "q", FMT_LEN_ll, STD_EXT, NULL, 0, 0 }, | |
738 | { "L", FMT_LEN_L, STD_C89, NULL, 0, 0 }, | |
739 | { "z", FMT_LEN_z, STD_C99, NULL, 0, 0 }, | |
740 | { "t", FMT_LEN_t, STD_C99, NULL, 0, 0 }, | |
741 | { "j", FMT_LEN_j, STD_C99, NULL, 0, 0 }, | |
742 | { NULL, 0, 0, NULL, 0, 0 } | |
743 | }; | |
744 | ||
745 | ||
746 | /* All tables for strfmon use STD_C89 everywhere, since -pedantic warnings | |
747 | make no sense for a format type not part of any C standard version. */ | |
748 | static const format_length_info strfmon_length_specs[] = | |
749 | { | |
750 | /* A GNU extension. */ | |
751 | { "L", FMT_LEN_L, STD_C89, NULL, 0, 0 }, | |
752 | { NULL, 0, 0, NULL, 0, 0 } | |
753 | }; | |
754 | ||
755 | static const format_flag_spec printf_flag_specs[] = | |
756 | { | |
757 | { ' ', 0, 0, N_("` ' flag"), N_("the ` ' printf flag"), STD_C89 }, | |
758 | { '+', 0, 0, N_("`+' flag"), N_("the `+' printf flag"), STD_C89 }, | |
759 | { '#', 0, 0, N_("`#' flag"), N_("the `#' printf flag"), STD_C89 }, | |
760 | { '0', 0, 0, N_("`0' flag"), N_("the `0' printf flag"), STD_C89 }, | |
761 | { '-', 0, 0, N_("`-' flag"), N_("the `-' printf flag"), STD_C89 }, | |
762 | { '\'', 0, 0, N_("`'' flag"), N_("the `'' printf flag"), STD_EXT }, | |
763 | { 'I', 0, 0, N_("`I' flag"), N_("the `I' printf flag"), STD_EXT }, | |
764 | { 'w', 0, 0, N_("field width"), N_("field width in printf format"), STD_C89 }, | |
765 | { 'p', 0, 0, N_("precision"), N_("precision in printf format"), STD_C89 }, | |
766 | { 'L', 0, 0, N_("length modifier"), N_("length modifier in printf format"), STD_C89 }, | |
767 | { 0, 0, 0, NULL, NULL, 0 } | |
768 | }; | |
769 | ||
770 | ||
771 | static const format_flag_pair printf_flag_pairs[] = | |
772 | { | |
773 | { ' ', '+', 1, 0 }, | |
774 | { '0', '-', 1, 0 }, | |
775 | { '0', 'p', 1, 'i' }, | |
776 | { 0, 0, 0, 0 } | |
777 | }; | |
778 | ||
779 | ||
780 | static const format_flag_spec scanf_flag_specs[] = | |
781 | { | |
782 | { '*', 0, 0, N_("assignment suppression"), N_("assignment suppression"), STD_C89 }, | |
783 | { 'a', 0, 0, N_("`a' flag"), N_("the `a' scanf flag"), STD_EXT }, | |
784 | { 'w', 0, 0, N_("field width"), N_("field width in scanf format"), STD_C89 }, | |
785 | { 'L', 0, 0, N_("length modifier"), N_("length modifier in scanf format"), STD_C89 }, | |
786 | { '\'', 0, 0, N_("`'' flag"), N_("the `'' scanf flag"), STD_EXT }, | |
787 | { 'I', 0, 0, N_("`I' flag"), N_("the `I' scanf flag"), STD_EXT }, | |
788 | { 0, 0, 0, NULL, NULL, 0 } | |
789 | }; | |
790 | ||
791 | ||
792 | static const format_flag_pair scanf_flag_pairs[] = | |
793 | { | |
794 | { '*', 'L', 0, 0 }, | |
795 | { 0, 0, 0, 0 } | |
796 | }; | |
797 | ||
798 | ||
799 | static const format_flag_spec strftime_flag_specs[] = | |
800 | { | |
801 | { '_', 0, 0, N_("`_' flag"), N_("the `_' strftime flag"), STD_EXT }, | |
802 | { '-', 0, 0, N_("`-' flag"), N_("the `-' strftime flag"), STD_EXT }, | |
803 | { '0', 0, 0, N_("`0' flag"), N_("the `0' strftime flag"), STD_EXT }, | |
804 | { '^', 0, 0, N_("`^' flag"), N_("the `^' strftime flag"), STD_EXT }, | |
805 | { '#', 0, 0, N_("`#' flag"), N_("the `#' strftime flag"), STD_EXT }, | |
806 | { 'w', 0, 0, N_("field width"), N_("field width in strftime format"), STD_EXT }, | |
807 | { 'E', 0, 0, N_("`E' modifier"), N_("the `E' strftime modifier"), STD_C99 }, | |
808 | { 'O', 0, 0, N_("`O' modifier"), N_("the `O' strftime modifier"), STD_C99 }, | |
809 | { 'O', 'o', 0, NULL, N_("the `O' modifier"), STD_EXT }, | |
810 | { 0, 0, 0, NULL, NULL, 0 } | |
811 | }; | |
812 | ||
813 | ||
814 | static const format_flag_pair strftime_flag_pairs[] = | |
815 | { | |
816 | { 'E', 'O', 0, 0 }, | |
817 | { '_', '-', 0, 0 }, | |
818 | { '_', '0', 0, 0 }, | |
819 | { '-', '0', 0, 0 }, | |
820 | { '^', '#', 0, 0 }, | |
821 | { 0, 0, 0, 0 } | |
822 | }; | |
823 | ||
824 | ||
825 | static const format_flag_spec strfmon_flag_specs[] = | |
826 | { | |
827 | { '=', 0, 1, N_("fill character"), N_("fill character in strfmon format"), STD_C89 }, | |
828 | { '^', 0, 0, N_("`^' flag"), N_("the `^' strfmon flag"), STD_C89 }, | |
829 | { '+', 0, 0, N_("`+' flag"), N_("the `+' strfmon flag"), STD_C89 }, | |
830 | { '(', 0, 0, N_("`(' flag"), N_("the `(' strfmon flag"), STD_C89 }, | |
831 | { '!', 0, 0, N_("`!' flag"), N_("the `!' strfmon flag"), STD_C89 }, | |
832 | { '-', 0, 0, N_("`-' flag"), N_("the `-' strfmon flag"), STD_C89 }, | |
833 | { 'w', 0, 0, N_("field width"), N_("field width in strfmon format"), STD_C89 }, | |
834 | { '#', 0, 0, N_("left precision"), N_("left precision in strfmon format"), STD_C89 }, | |
835 | { 'p', 0, 0, N_("right precision"), N_("right precision in strfmon format"), STD_C89 }, | |
836 | { 'L', 0, 0, N_("length modifier"), N_("length modifier in strfmon format"), STD_C89 }, | |
837 | { 0, 0, 0, NULL, NULL, 0 } | |
838 | }; | |
839 | ||
840 | static const format_flag_pair strfmon_flag_pairs[] = | |
841 | { | |
842 | { '+', '(', 0, 0 }, | |
843 | { 0, 0, 0, 0 } | |
844 | }; | |
845 | ||
846 | ||
847 | #define T_I &integer_type_node | |
848 | #define T89_I { STD_C89, NULL, T_I } | |
849 | #define T99_I { STD_C99, NULL, T_I } | |
850 | #define T_L &long_integer_type_node | |
851 | #define T89_L { STD_C89, NULL, T_L } | |
852 | #define T_LL &long_long_integer_type_node | |
853 | #define T9L_LL { STD_C9L, NULL, T_LL } | |
854 | #define TEX_LL { STD_EXT, NULL, T_LL } | |
855 | #define T_S &short_integer_type_node | |
856 | #define T89_S { STD_C89, NULL, T_S } | |
857 | #define T_UI &unsigned_type_node | |
858 | #define T89_UI { STD_C89, NULL, T_UI } | |
859 | #define T99_UI { STD_C99, NULL, T_UI } | |
860 | #define T_UL &long_unsigned_type_node | |
861 | #define T89_UL { STD_C89, NULL, T_UL } | |
862 | #define T_ULL &long_long_unsigned_type_node | |
863 | #define T9L_ULL { STD_C9L, NULL, T_ULL } | |
864 | #define TEX_ULL { STD_EXT, NULL, T_ULL } | |
865 | #define T_US &short_unsigned_type_node | |
866 | #define T89_US { STD_C89, NULL, T_US } | |
867 | #define T_F &float_type_node | |
868 | #define T89_F { STD_C89, NULL, T_F } | |
869 | #define T99_F { STD_C99, NULL, T_F } | |
870 | #define T_D &double_type_node | |
871 | #define T89_D { STD_C89, NULL, T_D } | |
872 | #define T99_D { STD_C99, NULL, T_D } | |
873 | #define T_LD &long_double_type_node | |
874 | #define T89_LD { STD_C89, NULL, T_LD } | |
875 | #define T99_LD { STD_C99, NULL, T_LD } | |
876 | #define T_C &char_type_node | |
877 | #define T89_C { STD_C89, NULL, T_C } | |
878 | #define T_SC &signed_char_type_node | |
879 | #define T99_SC { STD_C99, NULL, T_SC } | |
880 | #define T_UC &unsigned_char_type_node | |
881 | #define T99_UC { STD_C99, NULL, T_UC } | |
882 | #define T_V &void_type_node | |
883 | #define T89_V { STD_C89, NULL, T_V } | |
884 | #define T_W &wchar_type_node | |
885 | #define T94_W { STD_C94, "wchar_t", T_W } | |
886 | #define TEX_W { STD_EXT, "wchar_t", T_W } | |
887 | #define T_WI &wint_type_node | |
888 | #define T94_WI { STD_C94, "wint_t", T_WI } | |
889 | #define TEX_WI { STD_EXT, "wint_t", T_WI } | |
890 | #define T_ST &c_size_type_node | |
891 | #define T99_ST { STD_C99, "size_t", T_ST } | |
892 | #define T_SST &signed_size_type_node | |
893 | #define T99_SST { STD_C99, "signed size_t", T_SST } | |
894 | #define T_PD &ptrdiff_type_node | |
895 | #define T99_PD { STD_C99, "ptrdiff_t", T_PD } | |
896 | #define T_UPD &unsigned_ptrdiff_type_node | |
897 | #define T99_UPD { STD_C99, "unsigned ptrdiff_t", T_UPD } | |
898 | #define T_IM &intmax_type_node | |
899 | #define T99_IM { STD_C99, "intmax_t", T_IM } | |
900 | #define T_UIM &uintmax_type_node | |
901 | #define T99_UIM { STD_C99, "uintmax_t", T_UIM } | |
902 | ||
903 | static const format_char_info print_char_table[] = | |
904 | { | |
905 | /* C89 conversion specifiers. */ | |
906 | { "di", 0, STD_C89, { T89_I, T99_SC, T89_S, T89_L, T9L_LL, TEX_LL, T99_SST, T99_PD, T99_IM }, "-wp0 +'I", "i" }, | |
907 | { "oxX", 0, STD_C89, { T89_UI, T99_UC, T89_US, T89_UL, T9L_ULL, TEX_ULL, T99_ST, T99_UPD, T99_UIM }, "-wp0#", "i" }, | |
908 | { "u", 0, STD_C89, { T89_UI, T99_UC, T89_US, T89_UL, T9L_ULL, TEX_ULL, T99_ST, T99_UPD, T99_UIM }, "-wp0'I", "i" }, | |
909 | { "fgG", 0, STD_C89, { T89_D, BADLEN, BADLEN, T99_D, BADLEN, T89_LD, BADLEN, BADLEN, BADLEN }, "-wp0 +#'", "" }, | |
910 | { "eE", 0, STD_C89, { T89_D, BADLEN, BADLEN, T99_D, BADLEN, T89_LD, BADLEN, BADLEN, BADLEN }, "-wp0 +#", "" }, | |
911 | { "c", 0, STD_C89, { T89_I, BADLEN, BADLEN, T94_WI, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "-w", "" }, | |
912 | { "s", 1, STD_C89, { T89_C, BADLEN, BADLEN, T94_W, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "-wp", "cR" }, | |
913 | { "p", 1, STD_C89, { T89_V, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "-w", "c" }, | |
914 | { "n", 1, STD_C89, { T89_I, T99_SC, T89_S, T89_L, T9L_LL, BADLEN, T99_SST, T99_PD, T99_IM }, "", "W" }, | |
915 | /* C99 conversion specifiers. */ | |
916 | { "F", 0, STD_C99, { T99_D, BADLEN, BADLEN, T99_D, BADLEN, T99_LD, BADLEN, BADLEN, BADLEN }, "-wp0 +#'", "" }, | |
917 | { "aA", 0, STD_C99, { T99_D, BADLEN, BADLEN, T99_D, BADLEN, T99_LD, BADLEN, BADLEN, BADLEN }, "-wp0 +#", "" }, | |
918 | /* X/Open conversion specifiers. */ | |
919 | { "C", 0, STD_EXT, { TEX_WI, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "-w", "" }, | |
920 | { "S", 1, STD_EXT, { TEX_W, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "-wp", "R" }, | |
921 | /* GNU conversion specifiers. */ | |
922 | { "m", 0, STD_EXT, { T89_V, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "-wp", "" }, | |
923 | { NULL, 0, 0, NOLENGTHS, NULL, NULL } | |
924 | }; | |
925 | ||
926 | static const format_char_info scan_char_table[] = | |
927 | { | |
928 | /* C89 conversion specifiers. */ | |
929 | { "di", 1, STD_C89, { T89_I, T99_SC, T89_S, T89_L, T9L_LL, TEX_LL, T99_SST, T99_PD, T99_IM }, "*w'I", "W" }, | |
930 | { "u", 1, STD_C89, { T89_UI, T99_UC, T89_US, T89_UL, T9L_ULL, TEX_ULL, T99_ST, T99_UPD, T99_UIM }, "*w'I", "W" }, | |
931 | { "oxX", 1, STD_C89, { T89_UI, T99_UC, T89_US, T89_UL, T9L_ULL, TEX_ULL, T99_ST, T99_UPD, T99_UIM }, "*w", "W" }, | |
932 | { "efgEG", 1, STD_C89, { T89_F, BADLEN, BADLEN, T89_D, BADLEN, T89_LD, BADLEN, BADLEN, BADLEN }, "*w'", "W" }, | |
933 | { "c", 1, STD_C89, { T89_C, BADLEN, BADLEN, T94_W, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "*w", "cW" }, | |
934 | { "s", 1, STD_C89, { T89_C, BADLEN, BADLEN, T94_W, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "*aw", "cW" }, | |
935 | { "[", 1, STD_C89, { T89_C, BADLEN, BADLEN, T94_W, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "*aw", "cW[" }, | |
936 | { "p", 2, STD_C89, { T89_V, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "*w", "W" }, | |
937 | { "n", 1, STD_C89, { T89_I, T99_SC, T89_S, T89_L, T9L_LL, BADLEN, T99_SST, T99_PD, T99_IM }, "", "W" }, | |
938 | /* C99 conversion specifiers. */ | |
939 | { "FaA", 1, STD_C99, { T99_F, BADLEN, BADLEN, T99_D, BADLEN, T99_LD, BADLEN, BADLEN, BADLEN }, "*w'", "W" }, | |
940 | /* X/Open conversion specifiers. */ | |
941 | { "C", 1, STD_EXT, { TEX_W, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "*w", "W" }, | |
942 | { "S", 1, STD_EXT, { TEX_W, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "*aw", "W" }, | |
943 | { NULL, 0, 0, NOLENGTHS, NULL, NULL } | |
944 | }; | |
945 | ||
946 | static const format_char_info time_char_table[] = | |
947 | { | |
948 | /* C89 conversion specifiers. */ | |
949 | { "ABZab", 0, STD_C89, NOLENGTHS, "^#", "" }, | |
950 | { "cx", 0, STD_C89, NOLENGTHS, "E", "3" }, | |
951 | { "HIMSUWdmw", 0, STD_C89, NOLENGTHS, "-_0Ow", "" }, | |
952 | { "j", 0, STD_C89, NOLENGTHS, "-_0Ow", "o" }, | |
953 | { "p", 0, STD_C89, NOLENGTHS, "#", "" }, | |
954 | { "X", 0, STD_C89, NOLENGTHS, "E", "" }, | |
955 | { "y", 0, STD_C89, NOLENGTHS, "EO-_0w", "4" }, | |
956 | { "Y", 0, STD_C89, NOLENGTHS, "-_0EOw", "o" }, | |
957 | { "%", 0, STD_C89, NOLENGTHS, "", "" }, | |
958 | /* C99 conversion specifiers. */ | |
959 | { "C", 0, STD_C99, NOLENGTHS, "-_0EOw", "o" }, | |
960 | { "D", 0, STD_C99, NOLENGTHS, "", "2" }, | |
961 | { "eVu", 0, STD_C99, NOLENGTHS, "-_0Ow", "" }, | |
962 | { "FRTnrt", 0, STD_C99, NOLENGTHS, "", "" }, | |
963 | { "g", 0, STD_C99, NOLENGTHS, "O-_0w", "2o" }, | |
964 | { "G", 0, STD_C99, NOLENGTHS, "-_0Ow", "o" }, | |
965 | { "h", 0, STD_C99, NOLENGTHS, "^#", "" }, | |
966 | { "z", 0, STD_C99, NOLENGTHS, "O", "o" }, | |
967 | /* GNU conversion specifiers. */ | |
968 | { "kls", 0, STD_EXT, NOLENGTHS, "-_0Ow", "" }, | |
969 | { "P", 0, STD_EXT, NOLENGTHS, "", "" }, | |
970 | { NULL, 0, 0, NOLENGTHS, NULL, NULL } | |
971 | }; | |
972 | ||
973 | static const format_char_info monetary_char_table[] = | |
974 | { | |
975 | { "in", 0, STD_C89, { T89_D, BADLEN, BADLEN, BADLEN, BADLEN, T89_LD, BADLEN, BADLEN, BADLEN }, "=^+(!-w#p", "" }, | |
976 | { NULL, 0, 0, NOLENGTHS, NULL, NULL } | |
977 | }; | |
978 | ||
979 | ||
980 | /* This must be in the same order as enum format_type. */ | |
981 | static const format_kind_info format_types[] = | |
982 | { | |
983 | { "printf", printf_length_specs, print_char_table, " +#0-'I", NULL, | |
984 | printf_flag_specs, printf_flag_pairs, | |
985 | FMT_FLAG_ARG_CONVERT|FMT_FLAG_DOLLAR_MULTIPLE|FMT_FLAG_USE_DOLLAR|FMT_FLAG_EMPTY_PREC_OK, | |
986 | 'w', 0, 'p', 0, 'L', | |
987 | &integer_type_node, &integer_type_node | |
988 | }, | |
989 | { "scanf", scanf_length_specs, scan_char_table, "*'I", NULL, | |
990 | scanf_flag_specs, scanf_flag_pairs, | |
991 | FMT_FLAG_ARG_CONVERT|FMT_FLAG_SCANF_A_KLUDGE|FMT_FLAG_USE_DOLLAR|FMT_FLAG_ZERO_WIDTH_BAD, | |
992 | 'w', 0, 0, '*', 'L', | |
993 | NULL, NULL | |
994 | }, | |
995 | { "strftime", NULL, time_char_table, "_-0^#", "EO", | |
996 | strftime_flag_specs, strftime_flag_pairs, | |
997 | FMT_FLAG_FANCY_PERCENT_OK, 'w', 0, 0, 0, 0, | |
998 | NULL, NULL | |
999 | }, | |
1000 | { "strfmon", strfmon_length_specs, monetary_char_table, "=^+(!-", NULL, | |
1001 | strfmon_flag_specs, strfmon_flag_pairs, | |
1002 | FMT_FLAG_ARG_CONVERT, 'w', '#', 'p', 0, 'L', | |
1003 | NULL, NULL | |
1004 | } | |
1005 | }; | |
1006 | ||
1007 | ||
1008 | /* Structure detailing the results of checking a format function call | |
1009 | where the format expression may be a conditional expression with | |
1010 | many leaves resulting from nested conditional expressions. */ | |
1011 | typedef struct | |
1012 | { | |
1013 | /* Number of leaves of the format argument that could not be checked | |
1014 | as they were not string literals. */ | |
1015 | int number_non_literal; | |
1016 | /* Number of leaves of the format argument that were null pointers or | |
1017 | string literals, but had extra format arguments. */ | |
1018 | int number_extra_args; | |
1019 | /* Number of leaves of the format argument that were null pointers or | |
1020 | string literals, but had extra format arguments and used $ operand | |
1021 | numbers. */ | |
1022 | int number_dollar_extra_args; | |
1023 | /* Number of leaves of the format argument that were wide string | |
1024 | literals. */ | |
1025 | int number_wide; | |
1026 | /* Number of leaves of the format argument that were empty strings. */ | |
1027 | int number_empty; | |
1028 | /* Number of leaves of the format argument that were unterminated | |
1029 | strings. */ | |
1030 | int number_unterminated; | |
1031 | /* Number of leaves of the format argument that were not counted above. */ | |
1032 | int number_other; | |
1033 | } format_check_results; | |
1034 | ||
1035 | static void check_format_info PARAMS ((int *, function_format_info *, tree)); | |
1036 | static void check_format_info_recurse PARAMS ((int *, format_check_results *, | |
1037 | function_format_info *, tree, | |
1038 | tree, int)); | |
1039 | static void check_format_info_main PARAMS ((int *, format_check_results *, | |
1040 | function_format_info *, | |
1041 | const char *, int, tree, int)); | |
1042 | static void status_warning PARAMS ((int *, const char *, ...)) | |
1043 | ATTRIBUTE_PRINTF_2; | |
1044 | ||
1045 | static void init_dollar_format_checking PARAMS ((int, tree)); | |
1046 | static int maybe_read_dollar_number PARAMS ((int *, const char **, int, | |
1047 | tree, tree *, | |
1048 | const format_kind_info *)); | |
1049 | static void finish_dollar_format_checking PARAMS ((int *, format_check_results *)); | |
1050 | ||
1051 | static const format_flag_spec *get_flag_spec PARAMS ((const format_flag_spec *, | |
1052 | int, const char *)); | |
1053 | ||
1054 | static void check_format_types PARAMS ((int *, format_wanted_type *)); | |
1055 | ||
1056 | /* Decode a format type from a string, returning the type, or | |
1057 | format_type_error if not valid, in which case the caller should print an | |
1058 | error message. */ | |
1059 | static enum format_type | |
1060 | decode_format_type (s) | |
1061 | const char *s; | |
1062 | { | |
1063 | int i; | |
1064 | int slen; | |
1065 | slen = strlen (s); | |
1066 | for (i = 0; i < (int) format_type_error; i++) | |
1067 | { | |
1068 | int alen; | |
1069 | if (!strcmp (s, format_types[i].name)) | |
1070 | break; | |
1071 | alen = strlen (format_types[i].name); | |
1072 | if (slen == alen + 4 && s[0] == '_' && s[1] == '_' | |
1073 | && s[slen - 1] == '_' && s[slen - 2] == '_' | |
1074 | && !strncmp (s + 2, format_types[i].name, alen)) | |
1075 | break; | |
1076 | } | |
1077 | return ((enum format_type) i); | |
1078 | } | |
1079 | ||
1080 | \f | |
1081 | /* Check the argument list of a call to printf, scanf, etc. | |
1082 | NAME is the function identifier. | |
1083 | ASSEMBLER_NAME is the function's assembler identifier. | |
1084 | (Either NAME or ASSEMBLER_NAME, but not both, may be NULL_TREE.) | |
1085 | PARAMS is the list of argument values. Also, if -Wmissing-format-attribute, | |
1086 | warn for calls to vprintf or vscanf in functions with no such format | |
1087 | attribute themselves. */ | |
1088 | ||
1089 | void | |
1090 | check_function_format (status, name, assembler_name, params) | |
1091 | int *status; | |
1092 | tree name; | |
1093 | tree assembler_name; | |
1094 | tree params; | |
1095 | { | |
1096 | function_format_info *info; | |
1097 | ||
1098 | /* See if this function is a format function. */ | |
1099 | for (info = function_format_list; info; info = info->next) | |
1100 | { | |
1101 | if (info->assembler_name | |
1102 | ? (info->assembler_name == assembler_name) | |
1103 | : (info->name == name)) | |
1104 | { | |
1105 | /* Yup; check it. */ | |
1106 | check_format_info (status, info, params); | |
1107 | if (warn_missing_format_attribute && info->first_arg_num == 0 | |
dbbbbf3b JDA |
1108 | && (format_types[info->format_type].flags |
1109 | & (int) FMT_FLAG_ARG_CONVERT)) | |
1312c143 JM |
1110 | { |
1111 | function_format_info *info2; | |
1112 | for (info2 = function_format_list; info2; info2 = info2->next) | |
1113 | if ((info2->assembler_name | |
1114 | ? (info2->assembler_name == DECL_ASSEMBLER_NAME (current_function_decl)) | |
1115 | : (info2->name == DECL_NAME (current_function_decl))) | |
1116 | && info2->format_type == info->format_type) | |
1117 | break; | |
1118 | if (info2 == NULL) | |
1119 | { | |
1120 | /* Check if the current function has a parameter to which | |
1121 | the format attribute could be attached; if not, it | |
1122 | can't be a candidate for a format attribute, despite | |
1123 | the vprintf-like or vscanf-like call. */ | |
1124 | tree args; | |
1125 | for (args = DECL_ARGUMENTS (current_function_decl); | |
1126 | args != 0; | |
1127 | args = TREE_CHAIN (args)) | |
1128 | { | |
1129 | if (TREE_CODE (TREE_TYPE (args)) == POINTER_TYPE | |
1130 | && (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (args))) | |
1131 | == char_type_node)) | |
1132 | break; | |
1133 | } | |
1134 | if (args != 0) | |
1135 | warning ("function might be possible candidate for `%s' format attribute", | |
1136 | format_types[info->format_type].name); | |
1137 | } | |
1138 | } | |
1139 | break; | |
1140 | } | |
1141 | } | |
1142 | } | |
1143 | ||
1144 | /* This function replaces `warning' inside the printf format checking | |
1145 | functions. If the `status' parameter is non-NULL, then it is | |
1146 | dereferenced and set to 1 whenever a warning is caught. Otherwise | |
1147 | it warns as usual by replicating the innards of the warning | |
1148 | function from diagnostic.c. */ | |
1149 | static void | |
1150 | status_warning VPARAMS ((int *status, const char *msgid, ...)) | |
1151 | { | |
1152 | #ifndef ANSI_PROTOTYPES | |
1153 | int *status; | |
1154 | const char *msgid; | |
1155 | #endif | |
1156 | va_list ap; | |
1157 | diagnostic_context dc; | |
1158 | ||
1159 | VA_START (ap, msgid); | |
1160 | ||
1161 | #ifndef ANSI_PROTOTYPES | |
1162 | status = va_arg (ap, int *); | |
1163 | msgid = va_arg (ap, const char *); | |
1164 | #endif | |
1165 | ||
1166 | if (status) | |
1167 | *status = 1; | |
1168 | else | |
1169 | { | |
1170 | /* This duplicates the warning function behavior. */ | |
1171 | set_diagnostic_context | |
1172 | (&dc, msgid, &ap, input_filename, lineno, /* warn = */ 1); | |
1173 | report_diagnostic (&dc); | |
1174 | } | |
1175 | ||
1176 | va_end (ap); | |
1177 | } | |
1178 | ||
1179 | /* Variables used by the checking of $ operand number formats. */ | |
1180 | static char *dollar_arguments_used = NULL; | |
1181 | static int dollar_arguments_alloc = 0; | |
1182 | static int dollar_arguments_count; | |
1183 | static int dollar_first_arg_num; | |
1184 | static int dollar_max_arg_used; | |
1185 | static int dollar_format_warned; | |
1186 | ||
1187 | /* Initialize the checking for a format string that may contain $ | |
1188 | parameter number specifications; we will need to keep track of whether | |
1189 | each parameter has been used. FIRST_ARG_NUM is the number of the first | |
1190 | argument that is a parameter to the format, or 0 for a vprintf-style | |
1191 | function; PARAMS is the list of arguments starting at this argument. */ | |
1192 | ||
1193 | static void | |
1194 | init_dollar_format_checking (first_arg_num, params) | |
1195 | int first_arg_num; | |
1196 | tree params; | |
1197 | { | |
1198 | dollar_first_arg_num = first_arg_num; | |
1199 | dollar_arguments_count = 0; | |
1200 | dollar_max_arg_used = 0; | |
1201 | dollar_format_warned = 0; | |
1202 | if (first_arg_num > 0) | |
1203 | { | |
1204 | while (params) | |
1205 | { | |
1206 | dollar_arguments_count++; | |
1207 | params = TREE_CHAIN (params); | |
1208 | } | |
1209 | } | |
1210 | if (dollar_arguments_alloc < dollar_arguments_count) | |
1211 | { | |
1212 | if (dollar_arguments_used) | |
1213 | free (dollar_arguments_used); | |
1214 | dollar_arguments_alloc = dollar_arguments_count; | |
1215 | dollar_arguments_used = xmalloc (dollar_arguments_alloc); | |
1216 | } | |
1217 | if (dollar_arguments_alloc) | |
1218 | memset (dollar_arguments_used, 0, dollar_arguments_alloc); | |
1219 | } | |
1220 | ||
1221 | ||
1222 | /* Look for a decimal number followed by a $ in *FORMAT. If DOLLAR_NEEDED | |
1223 | is set, it is an error if one is not found; otherwise, it is OK. If | |
1224 | such a number is found, check whether it is within range and mark that | |
1225 | numbered operand as being used for later checking. Returns the operand | |
1226 | number if found and within range, zero if no such number was found and | |
1227 | this is OK, or -1 on error. PARAMS points to the first operand of the | |
1228 | format; PARAM_PTR is made to point to the parameter referred to. If | |
1229 | a $ format is found, *FORMAT is updated to point just after it. */ | |
1230 | ||
1231 | static int | |
1232 | maybe_read_dollar_number (status, format, dollar_needed, params, param_ptr, | |
1233 | fki) | |
1234 | int *status; | |
1235 | const char **format; | |
1236 | int dollar_needed; | |
1237 | tree params; | |
1238 | tree *param_ptr; | |
1239 | const format_kind_info *fki; | |
1240 | { | |
1241 | int argnum; | |
1242 | int overflow_flag; | |
1243 | const char *fcp = *format; | |
1244 | if (*fcp < '0' || *fcp > '9') | |
1245 | { | |
1246 | if (dollar_needed) | |
1247 | { | |
1248 | status_warning (status, "missing $ operand number in format"); | |
1249 | return -1; | |
1250 | } | |
1251 | else | |
1252 | return 0; | |
1253 | } | |
1254 | argnum = 0; | |
1255 | overflow_flag = 0; | |
1256 | while (*fcp >= '0' && *fcp <= '9') | |
1257 | { | |
1258 | int nargnum; | |
1259 | nargnum = 10 * argnum + (*fcp - '0'); | |
1260 | if (nargnum < 0 || nargnum / 10 != argnum) | |
1261 | overflow_flag = 1; | |
1262 | argnum = nargnum; | |
1263 | fcp++; | |
1264 | } | |
1265 | if (*fcp != '$') | |
1266 | { | |
1267 | if (dollar_needed) | |
1268 | { | |
1269 | status_warning (status, "missing $ operand number in format"); | |
1270 | return -1; | |
1271 | } | |
1272 | else | |
1273 | return 0; | |
1274 | } | |
1275 | *format = fcp + 1; | |
1276 | if (pedantic && !dollar_format_warned) | |
1277 | { | |
1278 | status_warning (status, | |
1279 | "%s does not support %%n$ operand number formats", | |
1280 | C_STD_NAME (STD_EXT)); | |
1281 | dollar_format_warned = 1; | |
1282 | } | |
1283 | if (overflow_flag || argnum == 0 | |
1284 | || (dollar_first_arg_num && argnum > dollar_arguments_count)) | |
1285 | { | |
1286 | status_warning (status, "operand number out of range in format"); | |
1287 | return -1; | |
1288 | } | |
1289 | if (argnum > dollar_max_arg_used) | |
1290 | dollar_max_arg_used = argnum; | |
1291 | /* For vprintf-style functions we may need to allocate more memory to | |
1292 | track which arguments are used. */ | |
1293 | while (dollar_arguments_alloc < dollar_max_arg_used) | |
1294 | { | |
1295 | int nalloc; | |
1296 | nalloc = 2 * dollar_arguments_alloc + 16; | |
1297 | dollar_arguments_used = xrealloc (dollar_arguments_used, nalloc); | |
1298 | memset (dollar_arguments_used + dollar_arguments_alloc, 0, | |
1299 | nalloc - dollar_arguments_alloc); | |
1300 | dollar_arguments_alloc = nalloc; | |
1301 | } | |
dbbbbf3b | 1302 | if (!(fki->flags & (int) FMT_FLAG_DOLLAR_MULTIPLE) |
1312c143 JM |
1303 | && dollar_arguments_used[argnum - 1] == 1) |
1304 | { | |
1305 | dollar_arguments_used[argnum - 1] = 2; | |
1306 | status_warning (status, | |
1307 | "format argument %d used more than once in %s format", | |
1308 | argnum, fki->name); | |
1309 | } | |
1310 | else | |
1311 | dollar_arguments_used[argnum - 1] = 1; | |
1312 | if (dollar_first_arg_num) | |
1313 | { | |
1314 | int i; | |
1315 | *param_ptr = params; | |
1316 | for (i = 1; i < argnum && *param_ptr != 0; i++) | |
1317 | *param_ptr = TREE_CHAIN (*param_ptr); | |
1318 | ||
1319 | if (*param_ptr == 0) | |
1320 | { | |
1321 | /* This case shouldn't be caught here. */ | |
1322 | abort (); | |
1323 | } | |
1324 | } | |
1325 | else | |
1326 | *param_ptr = 0; | |
1327 | return argnum; | |
1328 | } | |
1329 | ||
1330 | ||
1331 | /* Finish the checking for a format string that used $ operand number formats | |
1332 | instead of non-$ formats. We check for unused operands before used ones | |
1333 | (a serious error, since the implementation of the format function | |
1334 | can't know what types to pass to va_arg to find the later arguments). | |
1335 | and for unused operands at the end of the format (if we know how many | |
1336 | arguments the format had, so not for vprintf). If there were operand | |
1337 | numbers out of range on a non-vprintf-style format, we won't have reached | |
1338 | here. */ | |
1339 | ||
1340 | static void | |
1341 | finish_dollar_format_checking (status, res) | |
1342 | int *status; | |
1343 | format_check_results *res; | |
1344 | { | |
1345 | int i; | |
1346 | for (i = 0; i < dollar_max_arg_used; i++) | |
1347 | { | |
1348 | if (!dollar_arguments_used[i]) | |
1349 | status_warning (status, "format argument %d unused before used argument %d in $-style format", | |
1350 | i + 1, dollar_max_arg_used); | |
1351 | } | |
1352 | if (dollar_first_arg_num && dollar_max_arg_used < dollar_arguments_count) | |
1353 | { | |
1354 | res->number_other--; | |
1355 | res->number_dollar_extra_args++; | |
1356 | } | |
1357 | } | |
1358 | ||
1359 | ||
1360 | /* Retrieve the specification for a format flag. SPEC contains the | |
1361 | specifications for format flags for the applicable kind of format. | |
1362 | FLAG is the flag in question. If PREDICATES is NULL, the basic | |
1363 | spec for that flag must be retrieved and this function aborts if | |
1364 | it cannot be found. If PREDICATES is not NULL, it is a string listing | |
1365 | possible predicates for the spec entry; if an entry predicated on any | |
1366 | of these is found, it is returned, otherwise NULL is returned. */ | |
1367 | ||
1368 | static const format_flag_spec * | |
1369 | get_flag_spec (spec, flag, predicates) | |
1370 | const format_flag_spec *spec; | |
1371 | int flag; | |
1372 | const char *predicates; | |
1373 | { | |
1374 | int i; | |
1375 | for (i = 0; spec[i].flag_char != 0; i++) | |
1376 | { | |
1377 | if (spec[i].flag_char != flag) | |
1378 | continue; | |
1379 | if (predicates != NULL) | |
1380 | { | |
1381 | if (spec[i].predicate != 0 | |
1382 | && strchr (predicates, spec[i].predicate) != 0) | |
1383 | return &spec[i]; | |
1384 | } | |
1385 | else if (spec[i].predicate == 0) | |
1386 | return &spec[i]; | |
1387 | } | |
1388 | if (predicates == NULL) | |
1389 | abort (); | |
1390 | else | |
1391 | return NULL; | |
1392 | } | |
1393 | ||
1394 | ||
1395 | /* Check the argument list of a call to printf, scanf, etc. | |
1396 | INFO points to the function_format_info structure. | |
1397 | PARAMS is the list of argument values. */ | |
1398 | ||
1399 | static void | |
1400 | check_format_info (status, info, params) | |
1401 | int *status; | |
1402 | function_format_info *info; | |
1403 | tree params; | |
1404 | { | |
1405 | int arg_num; | |
1406 | tree format_tree; | |
1407 | format_check_results res; | |
1408 | /* Skip to format argument. If the argument isn't available, there's | |
1409 | no work for us to do; prototype checking will catch the problem. */ | |
1410 | for (arg_num = 1; ; ++arg_num) | |
1411 | { | |
1412 | if (params == 0) | |
1413 | return; | |
1414 | if (arg_num == info->format_num) | |
1415 | break; | |
1416 | params = TREE_CHAIN (params); | |
1417 | } | |
1418 | format_tree = TREE_VALUE (params); | |
1419 | params = TREE_CHAIN (params); | |
1420 | if (format_tree == 0) | |
1421 | return; | |
1422 | ||
1423 | res.number_non_literal = 0; | |
1424 | res.number_extra_args = 0; | |
1425 | res.number_dollar_extra_args = 0; | |
1426 | res.number_wide = 0; | |
1427 | res.number_empty = 0; | |
1428 | res.number_unterminated = 0; | |
1429 | res.number_other = 0; | |
1430 | ||
1431 | check_format_info_recurse (status, &res, info, format_tree, params, arg_num); | |
1432 | ||
1433 | if (res.number_non_literal > 0) | |
1434 | { | |
1435 | /* Functions taking a va_list normally pass a non-literal format | |
1436 | string. These functions typically are declared with | |
1437 | first_arg_num == 0, so avoid warning in those cases. */ | |
dbbbbf3b | 1438 | if (!(format_types[info->format_type].flags & (int) FMT_FLAG_ARG_CONVERT)) |
1312c143 JM |
1439 | { |
1440 | /* For strftime-like formats, warn for not checking the format | |
1441 | string; but there are no arguments to check. */ | |
1442 | if (warn_format_nonliteral) | |
1443 | status_warning (status, "format not a string literal, format string not checked"); | |
1444 | } | |
1445 | else if (info->first_arg_num != 0) | |
1446 | { | |
1447 | /* If there are no arguments for the format at all, we may have | |
1448 | printf (foo) which is likely to be a security hole. */ | |
1449 | while (arg_num + 1 < info->first_arg_num) | |
1450 | { | |
1451 | if (params == 0) | |
1452 | break; | |
1453 | params = TREE_CHAIN (params); | |
1454 | ++arg_num; | |
1455 | } | |
1456 | if (params == 0 && (warn_format_nonliteral || warn_format_security)) | |
1457 | status_warning (status, "format not a string literal and no format arguments"); | |
1458 | else if (warn_format_nonliteral) | |
1459 | status_warning (status, "format not a string literal, argument types not checked"); | |
1460 | } | |
1461 | } | |
1462 | ||
1463 | /* If there were extra arguments to the format, normally warn. However, | |
1464 | the standard does say extra arguments are ignored, so in the specific | |
1465 | case where we have multiple leaves (conditional expressions or | |
1466 | ngettext) allow extra arguments if at least one leaf didn't have extra | |
1467 | arguments, but was otherwise OK (either non-literal or checked OK). | |
1468 | If the format is an empty string, this should be counted similarly to the | |
1469 | case of extra format arguments. */ | |
1470 | if (res.number_extra_args > 0 && res.number_non_literal == 0 | |
1471 | && res.number_other == 0 && warn_format_extra_args) | |
1472 | status_warning (status, "too many arguments for format"); | |
1473 | if (res.number_dollar_extra_args > 0 && res.number_non_literal == 0 | |
1474 | && res.number_other == 0 && warn_format_extra_args) | |
1475 | status_warning (status, "unused arguments in $-style format"); | |
1476 | if (res.number_empty > 0 && res.number_non_literal == 0 | |
1477 | && res.number_other == 0) | |
1478 | status_warning (status, "zero-length format string"); | |
1479 | ||
1480 | if (res.number_wide > 0) | |
1481 | status_warning (status, "format is a wide character string"); | |
1482 | ||
1483 | if (res.number_unterminated > 0) | |
1484 | status_warning (status, "unterminated format string"); | |
1485 | } | |
1486 | ||
1487 | ||
1488 | /* Recursively check a call to a format function. FORMAT_TREE is the | |
1489 | format parameter, which may be a conditional expression in which | |
1490 | both halves should be checked. ARG_NUM is the number of the | |
1491 | format argument; PARAMS points just after it in the argument list. */ | |
1492 | ||
1493 | static void | |
1494 | check_format_info_recurse (status, res, info, format_tree, params, arg_num) | |
1495 | int *status; | |
1496 | format_check_results *res; | |
1497 | function_format_info *info; | |
1498 | tree format_tree; | |
1499 | tree params; | |
1500 | int arg_num; | |
1501 | { | |
1502 | int format_length; | |
b5cd6849 | 1503 | HOST_WIDE_INT offset; |
1312c143 JM |
1504 | const char *format_chars; |
1505 | tree array_size = 0; | |
1506 | tree array_init; | |
1507 | ||
1508 | if (TREE_CODE (format_tree) == NOP_EXPR) | |
1509 | { | |
1510 | /* Strip coercion. */ | |
1511 | check_format_info_recurse (status, res, info, | |
1512 | TREE_OPERAND (format_tree, 0), params, | |
1513 | arg_num); | |
1514 | return; | |
1515 | } | |
1516 | ||
1517 | if (TREE_CODE (format_tree) == CALL_EXPR | |
1518 | && TREE_CODE (TREE_OPERAND (format_tree, 0)) == ADDR_EXPR | |
1519 | && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (format_tree, 0), 0)) | |
1520 | == FUNCTION_DECL)) | |
1521 | { | |
1522 | tree function = TREE_OPERAND (TREE_OPERAND (format_tree, 0), 0); | |
1523 | ||
1524 | /* See if this is a call to a known internationalization function | |
1525 | that modifies the format arg. */ | |
1526 | international_format_info *iinfo; | |
1527 | ||
1528 | for (iinfo = international_format_list; iinfo; iinfo = iinfo->next) | |
1529 | if (iinfo->assembler_name | |
1530 | ? (iinfo->assembler_name == DECL_ASSEMBLER_NAME (function)) | |
1531 | : (iinfo->name == DECL_NAME (function))) | |
1532 | { | |
1533 | tree inner_args; | |
1534 | int i; | |
1535 | ||
1536 | for (inner_args = TREE_OPERAND (format_tree, 1), i = 1; | |
1537 | inner_args != 0; | |
1538 | inner_args = TREE_CHAIN (inner_args), i++) | |
1539 | if (i == iinfo->format_num) | |
1540 | { | |
1541 | /* FIXME: with Marc Espie's __attribute__((nonnull)) | |
1542 | patch in GCC, we will have chained attributes, | |
1543 | and be able to handle functions like ngettext | |
1544 | with multiple format_arg attributes properly. */ | |
1545 | check_format_info_recurse (status, res, info, | |
1546 | TREE_VALUE (inner_args), params, | |
1547 | arg_num); | |
1548 | return; | |
1549 | } | |
1550 | } | |
1551 | } | |
1552 | ||
1553 | if (TREE_CODE (format_tree) == COND_EXPR) | |
1554 | { | |
1555 | /* Check both halves of the conditional expression. */ | |
1556 | check_format_info_recurse (status, res, info, | |
1557 | TREE_OPERAND (format_tree, 1), params, | |
1558 | arg_num); | |
1559 | check_format_info_recurse (status, res, info, | |
1560 | TREE_OPERAND (format_tree, 2), params, | |
1561 | arg_num); | |
1562 | return; | |
1563 | } | |
1564 | ||
1565 | if (integer_zerop (format_tree)) | |
1566 | { | |
1567 | /* FIXME: this warning should go away once Marc Espie's | |
1568 | __attribute__((nonnull)) patch is in. Instead, checking for | |
1569 | nonnull attributes should probably change this function to act | |
1570 | specially if info == NULL and add a res->number_null entry for | |
1571 | that case, or maybe add a function pointer to be called at | |
1572 | the end instead of hardcoding check_format_info_main. */ | |
1573 | status_warning (status, "null format string"); | |
1574 | ||
1575 | /* Skip to first argument to check, so we can see if this format | |
1576 | has any arguments (it shouldn't). */ | |
1577 | while (arg_num + 1 < info->first_arg_num) | |
1578 | { | |
1579 | if (params == 0) | |
1580 | return; | |
1581 | params = TREE_CHAIN (params); | |
1582 | ++arg_num; | |
1583 | } | |
1584 | ||
1585 | if (params == 0) | |
1586 | res->number_other++; | |
1587 | else | |
1588 | res->number_extra_args++; | |
1589 | ||
1590 | return; | |
1591 | } | |
1592 | ||
b5cd6849 JJ |
1593 | offset = 0; |
1594 | if (TREE_CODE (format_tree) == PLUS_EXPR) | |
1595 | { | |
1596 | tree arg0, arg1; | |
1597 | ||
1598 | arg0 = TREE_OPERAND (format_tree, 0); | |
1599 | arg1 = TREE_OPERAND (format_tree, 1); | |
1600 | STRIP_NOPS (arg0); | |
1601 | STRIP_NOPS (arg1); | |
1602 | if (TREE_CODE (arg1) == INTEGER_CST) | |
1603 | format_tree = arg0; | |
1604 | else if (TREE_CODE (arg0) == INTEGER_CST) | |
1605 | { | |
1606 | format_tree = arg1; | |
1607 | arg1 = arg0; | |
1608 | } | |
1609 | else | |
1610 | { | |
1611 | res->number_non_literal++; | |
1612 | return; | |
1613 | } | |
1614 | if (!host_integerp (arg1, 1)) | |
1615 | { | |
1616 | res->number_non_literal++; | |
1617 | return; | |
1618 | } | |
1619 | ||
1620 | offset = TREE_INT_CST_LOW (arg1); | |
1621 | } | |
1312c143 JM |
1622 | if (TREE_CODE (format_tree) != ADDR_EXPR) |
1623 | { | |
1624 | res->number_non_literal++; | |
1625 | return; | |
1626 | } | |
1627 | format_tree = TREE_OPERAND (format_tree, 0); | |
1628 | if (TREE_CODE (format_tree) == VAR_DECL | |
1629 | && TREE_CODE (TREE_TYPE (format_tree)) == ARRAY_TYPE | |
1630 | && (array_init = decl_constant_value (format_tree)) != format_tree | |
1631 | && TREE_CODE (array_init) == STRING_CST) | |
1632 | { | |
1633 | /* Extract the string constant initializer. Note that this may include | |
1634 | a trailing NUL character that is not in the array (e.g. | |
1635 | const char a[3] = "foo";). */ | |
1636 | array_size = DECL_SIZE_UNIT (format_tree); | |
1637 | format_tree = array_init; | |
1638 | } | |
1639 | if (TREE_CODE (format_tree) != STRING_CST) | |
1640 | { | |
1641 | res->number_non_literal++; | |
1642 | return; | |
1643 | } | |
1644 | if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (format_tree))) != char_type_node) | |
1645 | { | |
1646 | res->number_wide++; | |
1647 | return; | |
1648 | } | |
1649 | format_chars = TREE_STRING_POINTER (format_tree); | |
1650 | format_length = TREE_STRING_LENGTH (format_tree); | |
1651 | if (array_size != 0) | |
1652 | { | |
1653 | /* Variable length arrays can't be initialized. */ | |
1654 | if (TREE_CODE (array_size) != INTEGER_CST) | |
1655 | abort (); | |
1656 | if (host_integerp (array_size, 0)) | |
1657 | { | |
1658 | HOST_WIDE_INT array_size_value = TREE_INT_CST_LOW (array_size); | |
1659 | if (array_size_value > 0 | |
1660 | && array_size_value == (int) array_size_value | |
1661 | && format_length > array_size_value) | |
1662 | format_length = array_size_value; | |
1663 | } | |
1664 | } | |
b5cd6849 JJ |
1665 | if (offset) |
1666 | { | |
1667 | if (offset >= format_length) | |
1668 | { | |
1669 | res->number_non_literal++; | |
1670 | return; | |
1671 | } | |
1672 | format_chars += offset; | |
1673 | format_length -= offset; | |
1674 | } | |
1312c143 JM |
1675 | if (format_length < 1) |
1676 | { | |
1677 | res->number_unterminated++; | |
1678 | return; | |
1679 | } | |
1680 | if (format_length == 1) | |
1681 | { | |
1682 | res->number_empty++; | |
1683 | return; | |
1684 | } | |
1685 | if (format_chars[--format_length] != 0) | |
1686 | { | |
1687 | res->number_unterminated++; | |
1688 | return; | |
1689 | } | |
1690 | ||
1691 | /* Skip to first argument to check. */ | |
1692 | while (arg_num + 1 < info->first_arg_num) | |
1693 | { | |
1694 | if (params == 0) | |
1695 | return; | |
1696 | params = TREE_CHAIN (params); | |
1697 | ++arg_num; | |
1698 | } | |
1699 | /* Provisionally increment res->number_other; check_format_info_main | |
1700 | will decrement it if it finds there are extra arguments, but this way | |
1701 | need not adjust it for every return. */ | |
1702 | res->number_other++; | |
1703 | check_format_info_main (status, res, info, format_chars, format_length, | |
1704 | params, arg_num); | |
1705 | } | |
1706 | ||
1707 | ||
1708 | /* Do the main part of checking a call to a format function. FORMAT_CHARS | |
1709 | is the NUL-terminated format string (which at this point may contain | |
1710 | internal NUL characters); FORMAT_LENGTH is its length (excluding the | |
1711 | terminating NUL character). ARG_NUM is one less than the number of | |
1712 | the first format argument to check; PARAMS points to that format | |
1713 | argument in the list of arguments. */ | |
1714 | ||
1715 | static void | |
1716 | check_format_info_main (status, res, info, format_chars, format_length, | |
1717 | params, arg_num) | |
1718 | int *status; | |
1719 | format_check_results *res; | |
1720 | function_format_info *info; | |
1721 | const char *format_chars; | |
1722 | int format_length; | |
1723 | tree params; | |
1724 | int arg_num; | |
1725 | { | |
1726 | const char *orig_format_chars = format_chars; | |
1727 | tree first_fillin_param = params; | |
1728 | ||
1729 | const format_kind_info *fki = &format_types[info->format_type]; | |
1730 | const format_flag_spec *flag_specs = fki->flag_specs; | |
1731 | const format_flag_pair *bad_flag_pairs = fki->bad_flag_pairs; | |
1732 | ||
1733 | /* -1 if no conversions taking an operand have been found; 0 if one has | |
1734 | and it didn't use $; 1 if $ formats are in use. */ | |
1735 | int has_operand_number = -1; | |
1736 | ||
1737 | init_dollar_format_checking (info->first_arg_num, first_fillin_param); | |
1738 | ||
1739 | while (1) | |
1740 | { | |
1741 | int i; | |
1742 | int suppressed = FALSE; | |
1743 | const char *length_chars = NULL; | |
1744 | enum format_lengths length_chars_val = FMT_LEN_none; | |
1745 | enum format_std_version length_chars_std = STD_C89; | |
1746 | int format_char; | |
1747 | tree cur_param; | |
1748 | tree wanted_type; | |
1749 | int main_arg_num = 0; | |
1750 | tree main_arg_params = 0; | |
1751 | enum format_std_version wanted_type_std; | |
1752 | const char *wanted_type_name; | |
1753 | format_wanted_type width_wanted_type; | |
1754 | format_wanted_type precision_wanted_type; | |
1755 | format_wanted_type main_wanted_type; | |
1756 | format_wanted_type *first_wanted_type = NULL; | |
1757 | format_wanted_type *last_wanted_type = NULL; | |
1758 | const format_length_info *fli = NULL; | |
1759 | const format_char_info *fci = NULL; | |
1760 | char flag_chars[256]; | |
1761 | int aflag = 0; | |
1762 | if (*format_chars == 0) | |
1763 | { | |
1764 | if (format_chars - orig_format_chars != format_length) | |
1765 | status_warning (status, "embedded `\\0' in format"); | |
1766 | if (info->first_arg_num != 0 && params != 0 | |
1767 | && has_operand_number <= 0) | |
1768 | { | |
1769 | res->number_other--; | |
1770 | res->number_extra_args++; | |
1771 | } | |
1772 | if (has_operand_number > 0) | |
1773 | finish_dollar_format_checking (status, res); | |
1774 | return; | |
1775 | } | |
1776 | if (*format_chars++ != '%') | |
1777 | continue; | |
1778 | if (*format_chars == 0) | |
1779 | { | |
1780 | status_warning (status, "spurious trailing `%%' in format"); | |
1781 | continue; | |
1782 | } | |
1783 | if (*format_chars == '%') | |
1784 | { | |
1785 | ++format_chars; | |
1786 | continue; | |
1787 | } | |
1788 | flag_chars[0] = 0; | |
1789 | ||
dbbbbf3b | 1790 | if ((fki->flags & (int) FMT_FLAG_USE_DOLLAR) && has_operand_number != 0) |
1312c143 JM |
1791 | { |
1792 | /* Possibly read a $ operand number at the start of the format. | |
1793 | If one was previously used, one is required here. If one | |
1794 | is not used here, we can't immediately conclude this is a | |
1795 | format without them, since it could be printf %m or scanf %*. */ | |
1796 | int opnum; | |
1797 | opnum = maybe_read_dollar_number (status, &format_chars, 0, | |
1798 | first_fillin_param, | |
1799 | &main_arg_params, fki); | |
1800 | if (opnum == -1) | |
1801 | return; | |
1802 | else if (opnum > 0) | |
1803 | { | |
1804 | has_operand_number = 1; | |
1805 | main_arg_num = opnum + info->first_arg_num - 1; | |
1806 | } | |
1807 | } | |
1808 | ||
1809 | /* Read any format flags, but do not yet validate them beyond removing | |
1810 | duplicates, since in general validation depends on the rest of | |
1811 | the format. */ | |
1812 | while (*format_chars != 0 | |
1813 | && strchr (fki->flag_chars, *format_chars) != 0) | |
1814 | { | |
1815 | const format_flag_spec *s = get_flag_spec (flag_specs, | |
1816 | *format_chars, NULL); | |
1817 | if (strchr (flag_chars, *format_chars) != 0) | |
1818 | { | |
1819 | status_warning (status, "repeated %s in format", _(s->name)); | |
1820 | } | |
1821 | else | |
1822 | { | |
1823 | i = strlen (flag_chars); | |
1824 | flag_chars[i++] = *format_chars; | |
1825 | flag_chars[i] = 0; | |
1826 | } | |
1827 | if (s->skip_next_char) | |
1828 | { | |
1829 | ++format_chars; | |
1830 | if (*format_chars == 0) | |
1831 | { | |
1832 | status_warning (status, "missing fill character at end of strfmon format"); | |
1833 | return; | |
1834 | } | |
1835 | } | |
1836 | ++format_chars; | |
1837 | } | |
1838 | ||
1839 | /* Read any format width, possibly * or *m$. */ | |
1840 | if (fki->width_char != 0) | |
1841 | { | |
1842 | if (fki->width_type != NULL && *format_chars == '*') | |
1843 | { | |
1844 | i = strlen (flag_chars); | |
1845 | flag_chars[i++] = fki->width_char; | |
1846 | flag_chars[i] = 0; | |
1847 | /* "...a field width...may be indicated by an asterisk. | |
1848 | In this case, an int argument supplies the field width..." */ | |
1849 | ++format_chars; | |
1850 | if (params == 0) | |
1851 | { | |
1852 | status_warning (status, "too few arguments for format"); | |
1853 | return; | |
1854 | } | |
1855 | if (has_operand_number != 0) | |
1856 | { | |
1857 | int opnum; | |
1858 | opnum = maybe_read_dollar_number (status, &format_chars, | |
1859 | has_operand_number == 1, | |
1860 | first_fillin_param, | |
1861 | ¶ms, fki); | |
1862 | if (opnum == -1) | |
1863 | return; | |
1864 | else if (opnum > 0) | |
1865 | { | |
1866 | has_operand_number = 1; | |
1867 | arg_num = opnum + info->first_arg_num - 1; | |
1868 | } | |
1869 | else | |
1870 | has_operand_number = 0; | |
1871 | } | |
1872 | if (info->first_arg_num != 0) | |
1873 | { | |
1874 | cur_param = TREE_VALUE (params); | |
1875 | if (has_operand_number <= 0) | |
1876 | { | |
1877 | params = TREE_CHAIN (params); | |
1878 | ++arg_num; | |
1879 | } | |
1880 | width_wanted_type.wanted_type = *fki->width_type; | |
1881 | width_wanted_type.wanted_type_name = NULL; | |
1882 | width_wanted_type.pointer_count = 0; | |
1883 | width_wanted_type.char_lenient_flag = 0; | |
1884 | width_wanted_type.writing_in_flag = 0; | |
1885 | width_wanted_type.reading_from_flag = 0; | |
1886 | width_wanted_type.name = _("field width"); | |
1887 | width_wanted_type.param = cur_param; | |
1888 | width_wanted_type.arg_num = arg_num; | |
1889 | width_wanted_type.next = NULL; | |
1890 | if (last_wanted_type != 0) | |
1891 | last_wanted_type->next = &width_wanted_type; | |
1892 | if (first_wanted_type == 0) | |
1893 | first_wanted_type = &width_wanted_type; | |
1894 | last_wanted_type = &width_wanted_type; | |
1895 | } | |
1896 | } | |
1897 | else | |
1898 | { | |
1899 | /* Possibly read a numeric width. If the width is zero, | |
1900 | we complain if appropriate. */ | |
1901 | int non_zero_width_char = FALSE; | |
1902 | int found_width = FALSE; | |
1903 | while (ISDIGIT (*format_chars)) | |
1904 | { | |
1905 | found_width = TRUE; | |
1906 | if (*format_chars != '0') | |
1907 | non_zero_width_char = TRUE; | |
1908 | ++format_chars; | |
1909 | } | |
1910 | if (found_width && !non_zero_width_char && | |
dbbbbf3b | 1911 | (fki->flags & (int) FMT_FLAG_ZERO_WIDTH_BAD)) |
1312c143 JM |
1912 | status_warning (status, "zero width in %s format", |
1913 | fki->name); | |
1914 | if (found_width) | |
1915 | { | |
1916 | i = strlen (flag_chars); | |
1917 | flag_chars[i++] = fki->width_char; | |
1918 | flag_chars[i] = 0; | |
1919 | } | |
1920 | } | |
1921 | } | |
1922 | ||
1923 | /* Read any format left precision (must be a number, not *). */ | |
1924 | if (fki->left_precision_char != 0 && *format_chars == '#') | |
1925 | { | |
1926 | ++format_chars; | |
1927 | i = strlen (flag_chars); | |
1928 | flag_chars[i++] = fki->left_precision_char; | |
1929 | flag_chars[i] = 0; | |
1930 | if (!ISDIGIT (*format_chars)) | |
1931 | status_warning (status, "empty left precision in %s format", | |
1932 | fki->name); | |
1933 | while (ISDIGIT (*format_chars)) | |
1934 | ++format_chars; | |
1935 | } | |
1936 | ||
1937 | /* Read any format precision, possibly * or *m$. */ | |
1938 | if (fki->precision_char != 0 && *format_chars == '.') | |
1939 | { | |
1940 | ++format_chars; | |
1941 | i = strlen (flag_chars); | |
1942 | flag_chars[i++] = fki->precision_char; | |
1943 | flag_chars[i] = 0; | |
1944 | if (fki->precision_type != NULL && *format_chars == '*') | |
1945 | { | |
1946 | /* "...a...precision...may be indicated by an asterisk. | |
1947 | In this case, an int argument supplies the...precision." */ | |
1948 | ++format_chars; | |
1949 | if (has_operand_number != 0) | |
1950 | { | |
1951 | int opnum; | |
1952 | opnum = maybe_read_dollar_number (status, &format_chars, | |
1953 | has_operand_number == 1, | |
1954 | first_fillin_param, | |
1955 | ¶ms, fki); | |
1956 | if (opnum == -1) | |
1957 | return; | |
1958 | else if (opnum > 0) | |
1959 | { | |
1960 | has_operand_number = 1; | |
1961 | arg_num = opnum + info->first_arg_num - 1; | |
1962 | } | |
1963 | else | |
1964 | has_operand_number = 0; | |
1965 | } | |
1966 | if (info->first_arg_num != 0) | |
1967 | { | |
1968 | if (params == 0) | |
1969 | { | |
1970 | status_warning (status, "too few arguments for format"); | |
1971 | return; | |
1972 | } | |
1973 | cur_param = TREE_VALUE (params); | |
1974 | if (has_operand_number <= 0) | |
1975 | { | |
1976 | params = TREE_CHAIN (params); | |
1977 | ++arg_num; | |
1978 | } | |
1979 | precision_wanted_type.wanted_type = *fki->precision_type; | |
1980 | precision_wanted_type.wanted_type_name = NULL; | |
1981 | precision_wanted_type.pointer_count = 0; | |
1982 | precision_wanted_type.char_lenient_flag = 0; | |
1983 | precision_wanted_type.writing_in_flag = 0; | |
1984 | precision_wanted_type.reading_from_flag = 0; | |
1985 | precision_wanted_type.name = _("field precision"); | |
1986 | precision_wanted_type.param = cur_param; | |
1987 | precision_wanted_type.arg_num = arg_num; | |
1988 | precision_wanted_type.next = NULL; | |
1989 | if (last_wanted_type != 0) | |
1990 | last_wanted_type->next = &precision_wanted_type; | |
1991 | if (first_wanted_type == 0) | |
1992 | first_wanted_type = &precision_wanted_type; | |
1993 | last_wanted_type = &precision_wanted_type; | |
1994 | } | |
1995 | } | |
1996 | else | |
1997 | { | |
dbbbbf3b | 1998 | if (!(fki->flags & (int) FMT_FLAG_EMPTY_PREC_OK) |
1312c143 JM |
1999 | && !ISDIGIT (*format_chars)) |
2000 | status_warning (status, "empty precision in %s format", | |
2001 | fki->name); | |
2002 | while (ISDIGIT (*format_chars)) | |
2003 | ++format_chars; | |
2004 | } | |
2005 | } | |
2006 | ||
2007 | /* Read any length modifier, if this kind of format has them. */ | |
2008 | fli = fki->length_char_specs; | |
2009 | length_chars = NULL; | |
2010 | length_chars_val = FMT_LEN_none; | |
2011 | length_chars_std = STD_C89; | |
2012 | if (fli) | |
2013 | { | |
2014 | while (fli->name != 0 && fli->name[0] != *format_chars) | |
2015 | fli++; | |
2016 | if (fli->name != 0) | |
2017 | { | |
2018 | format_chars++; | |
2019 | if (fli->double_name != 0 && fli->name[0] == *format_chars) | |
2020 | { | |
2021 | format_chars++; | |
2022 | length_chars = fli->double_name; | |
2023 | length_chars_val = fli->double_index; | |
2024 | length_chars_std = fli->double_std; | |
2025 | } | |
2026 | else | |
2027 | { | |
2028 | length_chars = fli->name; | |
2029 | length_chars_val = fli->index; | |
2030 | length_chars_std = fli->std; | |
2031 | } | |
2032 | i = strlen (flag_chars); | |
2033 | flag_chars[i++] = fki->length_code_char; | |
2034 | flag_chars[i] = 0; | |
2035 | } | |
2036 | if (pedantic) | |
2037 | { | |
2038 | /* Warn if the length modifier is non-standard. */ | |
2039 | if (ADJ_STD (length_chars_std) > C_STD_VER) | |
2040 | status_warning (status, "%s does not support the `%s' %s length modifier", | |
2041 | C_STD_NAME (length_chars_std), length_chars, | |
2042 | fki->name); | |
2043 | } | |
2044 | } | |
2045 | ||
2046 | /* Read any modifier (strftime E/O). */ | |
2047 | if (fki->modifier_chars != NULL) | |
2048 | { | |
2049 | while (*format_chars != 0 | |
2050 | && strchr (fki->modifier_chars, *format_chars) != 0) | |
2051 | { | |
2052 | if (strchr (flag_chars, *format_chars) != 0) | |
2053 | { | |
2054 | const format_flag_spec *s = get_flag_spec (flag_specs, | |
2055 | *format_chars, NULL); | |
2056 | status_warning (status, "repeated %s in format", _(s->name)); | |
2057 | } | |
2058 | else | |
2059 | { | |
2060 | i = strlen (flag_chars); | |
2061 | flag_chars[i++] = *format_chars; | |
2062 | flag_chars[i] = 0; | |
2063 | } | |
2064 | ++format_chars; | |
2065 | } | |
2066 | } | |
2067 | ||
2068 | /* Handle the scanf allocation kludge. */ | |
dbbbbf3b | 2069 | if (fki->flags & (int) FMT_FLAG_SCANF_A_KLUDGE) |
1312c143 JM |
2070 | { |
2071 | if (*format_chars == 'a' && !flag_isoc99) | |
2072 | { | |
2073 | if (format_chars[1] == 's' || format_chars[1] == 'S' | |
2074 | || format_chars[1] == '[') | |
2075 | { | |
2076 | /* `a' is used as a flag. */ | |
2077 | i = strlen (flag_chars); | |
2078 | flag_chars[i++] = 'a'; | |
2079 | flag_chars[i] = 0; | |
2080 | format_chars++; | |
2081 | } | |
2082 | } | |
2083 | } | |
2084 | ||
2085 | format_char = *format_chars; | |
2086 | if (format_char == 0 | |
dbbbbf3b JDA |
2087 | || (!(fki->flags & (int) FMT_FLAG_FANCY_PERCENT_OK) |
2088 | && format_char == '%')) | |
1312c143 JM |
2089 | { |
2090 | status_warning (status, "conversion lacks type at end of format"); | |
2091 | continue; | |
2092 | } | |
2093 | format_chars++; | |
2094 | fci = fki->conversion_specs; | |
2095 | while (fci->format_chars != 0 | |
2096 | && strchr (fci->format_chars, format_char) == 0) | |
2097 | ++fci; | |
2098 | if (fci->format_chars == 0) | |
2099 | { | |
2100 | if (ISGRAPH(format_char)) | |
2101 | status_warning (status, "unknown conversion type character `%c' in format", | |
2102 | format_char); | |
2103 | else | |
2104 | status_warning (status, "unknown conversion type character 0x%x in format", | |
2105 | format_char); | |
2106 | continue; | |
2107 | } | |
2108 | if (pedantic) | |
2109 | { | |
2110 | if (ADJ_STD (fci->std) > C_STD_VER) | |
2111 | status_warning (status, "%s does not support the `%%%c' %s format", | |
2112 | C_STD_NAME (fci->std), format_char, fki->name); | |
2113 | } | |
2114 | ||
2115 | /* Validate the individual flags used, removing any that are invalid. */ | |
2116 | { | |
2117 | int d = 0; | |
2118 | for (i = 0; flag_chars[i] != 0; i++) | |
2119 | { | |
2120 | const format_flag_spec *s = get_flag_spec (flag_specs, | |
2121 | flag_chars[i], NULL); | |
2122 | flag_chars[i - d] = flag_chars[i]; | |
2123 | if (flag_chars[i] == fki->length_code_char) | |
2124 | continue; | |
2125 | if (strchr (fci->flag_chars, flag_chars[i]) == 0) | |
2126 | { | |
2127 | status_warning (status, "%s used with `%%%c' %s format", | |
2128 | _(s->name), format_char, fki->name); | |
2129 | d++; | |
2130 | continue; | |
2131 | } | |
2132 | if (pedantic) | |
2133 | { | |
2134 | const format_flag_spec *t; | |
2135 | if (ADJ_STD (s->std) > C_STD_VER) | |
2136 | status_warning (status, "%s does not support %s", | |
2137 | C_STD_NAME (s->std), _(s->long_name)); | |
2138 | t = get_flag_spec (flag_specs, flag_chars[i], fci->flags2); | |
2139 | if (t != NULL && ADJ_STD (t->std) > ADJ_STD (s->std)) | |
2140 | { | |
2141 | const char *long_name = (t->long_name != NULL | |
2142 | ? t->long_name | |
2143 | : s->long_name); | |
2144 | if (ADJ_STD (t->std) > C_STD_VER) | |
2145 | status_warning (status, "%s does not support %s with the `%%%c' %s format", | |
2146 | C_STD_NAME (t->std), _(long_name), | |
2147 | format_char, fki->name); | |
2148 | } | |
2149 | } | |
2150 | } | |
2151 | flag_chars[i - d] = 0; | |
2152 | } | |
2153 | ||
dbbbbf3b | 2154 | if ((fki->flags & (int) FMT_FLAG_SCANF_A_KLUDGE) |
1312c143 JM |
2155 | && strchr (flag_chars, 'a') != 0) |
2156 | aflag = 1; | |
2157 | ||
2158 | if (fki->suppression_char | |
2159 | && strchr (flag_chars, fki->suppression_char) != 0) | |
2160 | suppressed = 1; | |
2161 | ||
2162 | /* Validate the pairs of flags used. */ | |
2163 | for (i = 0; bad_flag_pairs[i].flag_char1 != 0; i++) | |
2164 | { | |
2165 | const format_flag_spec *s, *t; | |
2166 | if (strchr (flag_chars, bad_flag_pairs[i].flag_char1) == 0) | |
2167 | continue; | |
2168 | if (strchr (flag_chars, bad_flag_pairs[i].flag_char2) == 0) | |
2169 | continue; | |
2170 | if (bad_flag_pairs[i].predicate != 0 | |
2171 | && strchr (fci->flags2, bad_flag_pairs[i].predicate) == 0) | |
2172 | continue; | |
2173 | s = get_flag_spec (flag_specs, bad_flag_pairs[i].flag_char1, NULL); | |
2174 | t = get_flag_spec (flag_specs, bad_flag_pairs[i].flag_char2, NULL); | |
2175 | if (bad_flag_pairs[i].ignored) | |
2176 | { | |
2177 | if (bad_flag_pairs[i].predicate != 0) | |
2178 | status_warning (status, "%s ignored with %s and `%%%c' %s format", | |
2179 | _(s->name), _(t->name), format_char, | |
2180 | fki->name); | |
2181 | else | |
2182 | status_warning (status, "%s ignored with %s in %s format", | |
2183 | _(s->name), _(t->name), fki->name); | |
2184 | } | |
2185 | else | |
2186 | { | |
2187 | if (bad_flag_pairs[i].predicate != 0) | |
2188 | status_warning (status, "use of %s and %s together with `%%%c' %s format", | |
2189 | _(s->name), _(t->name), format_char, | |
2190 | fki->name); | |
2191 | else | |
2192 | status_warning (status, "use of %s and %s together in %s format", | |
2193 | _(s->name), _(t->name), fki->name); | |
2194 | } | |
2195 | } | |
2196 | ||
2197 | /* Give Y2K warnings. */ | |
2198 | if (warn_format_y2k) | |
2199 | { | |
2200 | int y2k_level = 0; | |
2201 | if (strchr (fci->flags2, '4') != 0) | |
2202 | if (strchr (flag_chars, 'E') != 0) | |
2203 | y2k_level = 3; | |
2204 | else | |
2205 | y2k_level = 2; | |
2206 | else if (strchr (fci->flags2, '3') != 0) | |
2207 | y2k_level = 3; | |
2208 | else if (strchr (fci->flags2, '2') != 0) | |
2209 | y2k_level = 2; | |
2210 | if (y2k_level == 3) | |
2211 | status_warning (status, "`%%%c' yields only last 2 digits of year in some locales", | |
2212 | format_char); | |
2213 | else if (y2k_level == 2) | |
2214 | status_warning (status, "`%%%c' yields only last 2 digits of year", format_char); | |
2215 | } | |
2216 | ||
2217 | if (strchr (fci->flags2, '[') != 0) | |
2218 | { | |
2219 | /* Skip over scan set, in case it happens to have '%' in it. */ | |
2220 | if (*format_chars == '^') | |
2221 | ++format_chars; | |
2222 | /* Find closing bracket; if one is hit immediately, then | |
2223 | it's part of the scan set rather than a terminator. */ | |
2224 | if (*format_chars == ']') | |
2225 | ++format_chars; | |
2226 | while (*format_chars && *format_chars != ']') | |
2227 | ++format_chars; | |
2228 | if (*format_chars != ']') | |
2229 | /* The end of the format string was reached. */ | |
2230 | status_warning (status, "no closing `]' for `%%[' format"); | |
2231 | } | |
2232 | ||
2233 | wanted_type = 0; | |
2234 | wanted_type_name = 0; | |
dbbbbf3b | 2235 | if (fki->flags & (int) FMT_FLAG_ARG_CONVERT) |
1312c143 JM |
2236 | { |
2237 | wanted_type = (fci->types[length_chars_val].type | |
2238 | ? *fci->types[length_chars_val].type : 0); | |
2239 | wanted_type_name = fci->types[length_chars_val].name; | |
2240 | wanted_type_std = fci->types[length_chars_val].std; | |
2241 | if (wanted_type == 0) | |
2242 | { | |
2243 | status_warning (status, "use of `%s' length modifier with `%c' type character", | |
2244 | length_chars, format_char); | |
2245 | /* Heuristic: skip one argument when an invalid length/type | |
2246 | combination is encountered. */ | |
2247 | arg_num++; | |
2248 | if (params == 0) | |
2249 | { | |
2250 | status_warning (status, "too few arguments for format"); | |
2251 | return; | |
2252 | } | |
2253 | params = TREE_CHAIN (params); | |
2254 | continue; | |
2255 | } | |
2256 | else if (pedantic | |
2257 | /* Warn if non-standard, provided it is more non-standard | |
2258 | than the length and type characters that may already | |
2259 | have been warned for. */ | |
2260 | && ADJ_STD (wanted_type_std) > ADJ_STD (length_chars_std) | |
2261 | && ADJ_STD (wanted_type_std) > ADJ_STD (fci->std)) | |
2262 | { | |
2263 | if (ADJ_STD (wanted_type_std) > C_STD_VER) | |
2264 | status_warning (status, "%s does not support the `%%%s%c' %s format", | |
2265 | C_STD_NAME (wanted_type_std), length_chars, | |
2266 | format_char, fki->name); | |
2267 | } | |
2268 | } | |
2269 | ||
2270 | /* Finally. . .check type of argument against desired type! */ | |
2271 | if (info->first_arg_num == 0) | |
2272 | continue; | |
2273 | if ((fci->pointer_count == 0 && wanted_type == void_type_node) | |
2274 | || suppressed) | |
2275 | { | |
2276 | if (main_arg_num != 0) | |
2277 | { | |
2278 | if (suppressed) | |
2279 | status_warning (status, "operand number specified with suppressed assignment"); | |
2280 | else | |
2281 | status_warning (status, "operand number specified for format taking no argument"); | |
2282 | } | |
2283 | } | |
2284 | else | |
2285 | { | |
2286 | if (main_arg_num != 0) | |
2287 | { | |
2288 | arg_num = main_arg_num; | |
2289 | params = main_arg_params; | |
2290 | } | |
2291 | else | |
2292 | { | |
2293 | ++arg_num; | |
2294 | if (has_operand_number > 0) | |
2295 | { | |
2296 | status_warning (status, "missing $ operand number in format"); | |
2297 | return; | |
2298 | } | |
2299 | else | |
2300 | has_operand_number = 0; | |
2301 | if (params == 0) | |
2302 | { | |
2303 | status_warning (status, "too few arguments for format"); | |
2304 | return; | |
2305 | } | |
2306 | } | |
2307 | cur_param = TREE_VALUE (params); | |
2308 | params = TREE_CHAIN (params); | |
2309 | main_wanted_type.wanted_type = wanted_type; | |
2310 | main_wanted_type.wanted_type_name = wanted_type_name; | |
2311 | main_wanted_type.pointer_count = fci->pointer_count + aflag; | |
2312 | main_wanted_type.char_lenient_flag = 0; | |
2313 | if (strchr (fci->flags2, 'c') != 0) | |
2314 | main_wanted_type.char_lenient_flag = 1; | |
2315 | main_wanted_type.writing_in_flag = 0; | |
2316 | main_wanted_type.reading_from_flag = 0; | |
2317 | if (aflag) | |
2318 | main_wanted_type.writing_in_flag = 1; | |
2319 | else | |
2320 | { | |
2321 | if (strchr (fci->flags2, 'W') != 0) | |
2322 | main_wanted_type.writing_in_flag = 1; | |
2323 | if (strchr (fci->flags2, 'R') != 0) | |
2324 | main_wanted_type.reading_from_flag = 1; | |
2325 | } | |
2326 | main_wanted_type.name = NULL; | |
2327 | main_wanted_type.param = cur_param; | |
2328 | main_wanted_type.arg_num = arg_num; | |
2329 | main_wanted_type.next = NULL; | |
2330 | if (last_wanted_type != 0) | |
2331 | last_wanted_type->next = &main_wanted_type; | |
2332 | if (first_wanted_type == 0) | |
2333 | first_wanted_type = &main_wanted_type; | |
2334 | last_wanted_type = &main_wanted_type; | |
2335 | } | |
2336 | ||
2337 | if (first_wanted_type != 0) | |
2338 | check_format_types (status, first_wanted_type); | |
2339 | ||
2340 | } | |
2341 | } | |
2342 | ||
2343 | ||
2344 | /* Check the argument types from a single format conversion (possibly | |
2345 | including width and precision arguments). */ | |
2346 | static void | |
2347 | check_format_types (status, types) | |
2348 | int *status; | |
2349 | format_wanted_type *types; | |
2350 | { | |
2351 | for (; types != 0; types = types->next) | |
2352 | { | |
2353 | tree cur_param; | |
2354 | tree cur_type; | |
2355 | tree orig_cur_type; | |
2356 | tree wanted_type; | |
2357 | tree promoted_type; | |
2358 | int arg_num; | |
2359 | int i; | |
2360 | int char_type_flag; | |
2361 | cur_param = types->param; | |
2362 | cur_type = TREE_TYPE (cur_param); | |
2363 | if (cur_type == error_mark_node) | |
2364 | continue; | |
2365 | char_type_flag = 0; | |
2366 | wanted_type = types->wanted_type; | |
2367 | arg_num = types->arg_num; | |
2368 | ||
2369 | /* The following should not occur here. */ | |
2370 | if (wanted_type == 0) | |
2371 | abort (); | |
2372 | if (wanted_type == void_type_node && types->pointer_count == 0) | |
2373 | abort (); | |
2374 | ||
2375 | if (types->pointer_count == 0) | |
2376 | { | |
2377 | promoted_type = simple_type_promotes_to (wanted_type); | |
2378 | if (promoted_type != NULL_TREE) | |
2379 | wanted_type = promoted_type; | |
2380 | } | |
2381 | ||
2382 | STRIP_NOPS (cur_param); | |
2383 | ||
2384 | /* Check the types of any additional pointer arguments | |
2385 | that precede the "real" argument. */ | |
2386 | for (i = 0; i < types->pointer_count; ++i) | |
2387 | { | |
2388 | if (TREE_CODE (cur_type) == POINTER_TYPE) | |
2389 | { | |
2390 | cur_type = TREE_TYPE (cur_type); | |
2391 | if (cur_type == error_mark_node) | |
2392 | break; | |
2393 | ||
2394 | /* Check for writing through a NULL pointer. */ | |
2395 | if (types->writing_in_flag | |
2396 | && i == 0 | |
2397 | && cur_param != 0 | |
2398 | && integer_zerop (cur_param)) | |
2399 | status_warning (status, | |
2400 | "writing through null pointer (arg %d)", | |
2401 | arg_num); | |
2402 | ||
2403 | /* Check for reading through a NULL pointer. */ | |
2404 | if (types->reading_from_flag | |
2405 | && i == 0 | |
2406 | && cur_param != 0 | |
2407 | && integer_zerop (cur_param)) | |
2408 | status_warning (status, | |
2409 | "reading through null pointer (arg %d)", | |
2410 | arg_num); | |
2411 | ||
2412 | if (cur_param != 0 && TREE_CODE (cur_param) == ADDR_EXPR) | |
2413 | cur_param = TREE_OPERAND (cur_param, 0); | |
2414 | else | |
2415 | cur_param = 0; | |
2416 | ||
2417 | /* See if this is an attempt to write into a const type with | |
2418 | scanf or with printf "%n". Note: the writing in happens | |
2419 | at the first indirection only, if for example | |
2420 | void * const * is passed to scanf %p; passing | |
2421 | const void ** is simply passing an incompatible type. */ | |
2422 | if (types->writing_in_flag | |
2423 | && i == 0 | |
2424 | && (TYPE_READONLY (cur_type) | |
2425 | || (cur_param != 0 | |
2426 | && (TREE_CODE_CLASS (TREE_CODE (cur_param)) == 'c' | |
2427 | || (DECL_P (cur_param) | |
2428 | && TREE_READONLY (cur_param)))))) | |
2429 | status_warning (status, "writing into constant object (arg %d)", arg_num); | |
2430 | ||
2431 | /* If there are extra type qualifiers beyond the first | |
2432 | indirection, then this makes the types technically | |
2433 | incompatible. */ | |
2434 | if (i > 0 | |
2435 | && pedantic | |
2436 | && (TYPE_READONLY (cur_type) | |
2437 | || TYPE_VOLATILE (cur_type) | |
2438 | || TYPE_RESTRICT (cur_type))) | |
2439 | status_warning (status, "extra type qualifiers in format argument (arg %d)", | |
2440 | arg_num); | |
2441 | ||
2442 | } | |
2443 | else | |
2444 | { | |
2445 | if (types->pointer_count == 1) | |
2446 | status_warning (status, "format argument is not a pointer (arg %d)", arg_num); | |
2447 | else | |
2448 | status_warning (status, "format argument is not a pointer to a pointer (arg %d)", arg_num); | |
2449 | break; | |
2450 | } | |
2451 | } | |
2452 | ||
2453 | if (i < types->pointer_count) | |
2454 | continue; | |
2455 | ||
2456 | orig_cur_type = cur_type; | |
2457 | cur_type = TYPE_MAIN_VARIANT (cur_type); | |
2458 | ||
2459 | /* Check whether the argument type is a character type. This leniency | |
2460 | only applies to certain formats, flagged with 'c'. | |
2461 | */ | |
2462 | if (types->char_lenient_flag) | |
2463 | char_type_flag = (cur_type == char_type_node | |
2464 | || cur_type == signed_char_type_node | |
2465 | || cur_type == unsigned_char_type_node); | |
2466 | ||
2467 | /* Check the type of the "real" argument, if there's a type we want. */ | |
2468 | if (wanted_type == cur_type) | |
2469 | continue; | |
2470 | /* If we want `void *', allow any pointer type. | |
2471 | (Anything else would already have got a warning.) | |
2472 | With -pedantic, only allow pointers to void and to character | |
2473 | types. */ | |
2474 | if (wanted_type == void_type_node | |
2475 | && (!pedantic || (i == 1 && char_type_flag))) | |
2476 | continue; | |
2477 | /* Don't warn about differences merely in signedness, unless | |
2478 | -pedantic. With -pedantic, warn if the type is a pointer | |
2479 | target and not a character type, and for character types at | |
2480 | a second level of indirection. */ | |
2481 | if (TREE_CODE (wanted_type) == INTEGER_TYPE | |
2482 | && TREE_CODE (cur_type) == INTEGER_TYPE | |
2483 | && (! pedantic || i == 0 || (i == 1 && char_type_flag)) | |
2484 | && (TREE_UNSIGNED (wanted_type) | |
2485 | ? wanted_type == unsigned_type (cur_type) | |
2486 | : wanted_type == signed_type (cur_type))) | |
2487 | continue; | |
2488 | /* Likewise, "signed char", "unsigned char" and "char" are | |
2489 | equivalent but the above test won't consider them equivalent. */ | |
2490 | if (wanted_type == char_type_node | |
2491 | && (! pedantic || i < 2) | |
2492 | && char_type_flag) | |
2493 | continue; | |
2494 | /* Now we have a type mismatch. */ | |
2495 | { | |
2496 | register const char *this; | |
2497 | register const char *that; | |
2498 | ||
2499 | this = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (wanted_type))); | |
2500 | that = 0; | |
2501 | if (TYPE_NAME (orig_cur_type) != 0 | |
2502 | && TREE_CODE (orig_cur_type) != INTEGER_TYPE | |
2503 | && !(TREE_CODE (orig_cur_type) == POINTER_TYPE | |
2504 | && TREE_CODE (TREE_TYPE (orig_cur_type)) == INTEGER_TYPE)) | |
2505 | { | |
2506 | if (TREE_CODE (TYPE_NAME (orig_cur_type)) == TYPE_DECL | |
2507 | && DECL_NAME (TYPE_NAME (orig_cur_type)) != 0) | |
2508 | that = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (orig_cur_type))); | |
2509 | else | |
2510 | that = IDENTIFIER_POINTER (TYPE_NAME (orig_cur_type)); | |
2511 | } | |
2512 | ||
2513 | /* A nameless type can't possibly match what the format wants. | |
2514 | So there will be a warning for it. | |
2515 | Make up a string to describe vaguely what it is. */ | |
2516 | if (that == 0) | |
2517 | { | |
2518 | if (TREE_CODE (orig_cur_type) == POINTER_TYPE) | |
2519 | that = "pointer"; | |
2520 | else | |
2521 | that = "different type"; | |
2522 | } | |
2523 | ||
2524 | /* Make the warning better in case of mismatch of int vs long. */ | |
2525 | if (TREE_CODE (orig_cur_type) == INTEGER_TYPE | |
2526 | && TREE_CODE (wanted_type) == INTEGER_TYPE | |
2527 | && TYPE_PRECISION (orig_cur_type) == TYPE_PRECISION (wanted_type) | |
2528 | && TYPE_NAME (orig_cur_type) != 0 | |
2529 | && TREE_CODE (TYPE_NAME (orig_cur_type)) == TYPE_DECL) | |
2530 | that = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (orig_cur_type))); | |
2531 | ||
2532 | if (strcmp (this, that) != 0) | |
2533 | { | |
2534 | /* There may be a better name for the format, e.g. size_t, | |
2535 | but we should allow for programs with a perverse typedef | |
2536 | making size_t something other than what the compiler | |
2537 | thinks. */ | |
2538 | if (types->wanted_type_name != 0 | |
2539 | && strcmp (types->wanted_type_name, that) != 0) | |
2540 | this = types->wanted_type_name; | |
2541 | if (types->name != 0) | |
2542 | status_warning (status, "%s is not type %s (arg %d)", types->name, this, | |
2543 | arg_num); | |
2544 | else | |
2545 | status_warning (status, "%s format, %s arg (arg %d)", this, that, arg_num); | |
2546 | } | |
2547 | } | |
2548 | } | |
2549 | } |