The Tcpdump Group git mirrors - libpcap/blob - diag-control.h

   1 /* -*- Mode: c; tab-width: 8; indent-tabs-mode: 1; c-basic-offset: 8; -*- */
   2 /*
   3  * Copyright (c) 1993, 1994, 1995, 1996, 1997
   4  *      The Regents of the University of California.  All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  * 3. All advertising materials mentioning features or use of this software
  15  *    must display the following acknowledgement:
  16  *      This product includes software developed by the Computer Systems
  17  *      Engineering Group at Lawrence Berkeley Laboratory.
  18  * 4. Neither the name of the University nor of the Laboratory may be used
  19  *    to endorse or promote products derived from this software without
  20  *    specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  */
  34
  35 #ifndef _diag_control_h
  36 #define _diag_control_h
  37
  38 #include "pcap/compiler-tests.h"
  39
  40 #if PCAP_IS_AT_LEAST_CLANG_VERSION(2,8) || \
  41     PCAP_IS_AT_LEAST_GNUC_VERSION(4,6) || \
  42     PCAP_IS_AT_LEAST_SUNC_VERSION(5,5)
  43   /*
  44    * All these compilers support this way of putting pragmas into #defines.
  45    * We use it only if we have a compiler that supports it; see below
  46    * for the code that uses it and the #defines that control whether
  47    * that code is used.
  48    */
  49   #define PCAP_DO_PRAGMA(x) _Pragma (#x)
  50 #endif
  51
  52 /*
  53  * Suppress "enum value not explicitly handled in switch" warnings.
  54  * We may have to build on multiple different Windows SDKs, so we
  55  * may not be able to include all enum values in a switch, as they
  56  * won't necessarily be defined on all the SDKs, and, unlike
  57  * #defines, there's no easy way to test whether a given enum has
  58  * a given value.  It *could* be done by the configure script or
  59  * CMake tests.
  60  */
  61 #if defined(_MSC_VER)
  62   #define DIAG_OFF_ENUM_SWITCH \
  63     __pragma(warning(push)) \
  64     __pragma(warning(disable:4061))
  65   #define DIAG_ON_ENUM_SWITCH \
  66     __pragma(warning(pop))
  67 #endif
  68
  69 /*
  70  * Suppress "switch statement has only a default case" warnings.
  71  * There's a switch in bpf_filter.c that only has additional
  72  * cases on Linux.
  73  */
  74 #if defined(_MSC_VER)
  75   #define DIAG_OFF_DEFAULT_ONLY_SWITCH \
  76     __pragma(warning(push)) \
  77     __pragma(warning(disable:4065))
  78   #define DIAG_ON_DEFAULT_ONLY_SWITCH \
  79     __pragma(warning(pop))
  80 #endif
  81
  82 /*
  83  * Suppress Flex, narrowing, and deprecation warnings.
  84  */
  85 #if PCAP_IS_AT_LEAST_CLANG_VERSION(2,8)
  86   /*
  87    * This is Clang 2.8 or later; we can use "clang diagnostic
  88    * ignored -Wxxx" and "clang diagnostic push/pop".
  89    *
  90    * Suppress -Wdocumentation warnings; GCC doesn't support -Wdocumentation,
  91    * at least according to the GCC 7.3 documentation.  Apparently, Flex
  92    * generates code that upsets at least some versions of Clang's
  93    * -Wdocumentation.
  94    *
  95    * (This could be clang-cl, which defines _MSC_VER, so test this
  96    * before testing _MSC_VER.)
  97    */
  98   #define DIAG_OFF_FLEX \
  99     PCAP_DO_PRAGMA(clang diagnostic push) \
 100     PCAP_DO_PRAGMA(clang diagnostic ignored "-Wsign-compare") \
 101     PCAP_DO_PRAGMA(clang diagnostic ignored "-Wdocumentation") \
 102     PCAP_DO_PRAGMA(clang diagnostic ignored "-Wshorten-64-to-32") \
 103     PCAP_DO_PRAGMA(clang diagnostic ignored "-Wmissing-noreturn") \
 104     PCAP_DO_PRAGMA(clang diagnostic ignored "-Wunused-parameter") \
 105     PCAP_DO_PRAGMA(clang diagnostic ignored "-Wunreachable-code")
 106   #define DIAG_ON_FLEX \
 107     PCAP_DO_PRAGMA(clang diagnostic pop)
 108
 109   /*
 110    * Suppress the only narrowing warnings you get from Clang.
 111    */
 112   #define DIAG_OFF_NARROWING \
 113     PCAP_DO_PRAGMA(clang diagnostic push) \
 114     PCAP_DO_PRAGMA(clang diagnostic ignored "-Wshorten-64-to-32")
 115
 116   #define DIAG_ON_NARROWING \
 117     PCAP_DO_PRAGMA(clang diagnostic pop)
 118
 119   /*
 120    * Suppress deprecation warnings.
 121    */
 122   #define DIAG_OFF_DEPRECATION \
 123     PCAP_DO_PRAGMA(clang diagnostic push) \
 124     PCAP_DO_PRAGMA(clang diagnostic ignored "-Wdeprecated-declarations")
 125   #define DIAG_ON_DEPRECATION \
 126     PCAP_DO_PRAGMA(clang diagnostic pop)
 127
 128   /*
 129    * When Clang correctly detects an old-style function prototype after
 130    * preprocessing, the warning can be irrelevant to this source tree because
 131    * the prototype comes from a system header macro.
 132    */
 133   #if PCAP_IS_AT_LEAST_CLANG_VERSION(5,0)
 134     #define DIAG_OFF_STRICT_PROTOTYPES \
 135       PCAP_DO_PRAGMA(clang diagnostic push) \
 136       PCAP_DO_PRAGMA(clang diagnostic ignored "-Wstrict-prototypes")
 137     #define DIAG_ON_STRICT_PROTOTYPES \
 138       PCAP_DO_PRAGMA(clang diagnostic pop)
 139   #endif
 140 #elif defined(_MSC_VER)
 141   /*
 142    * This is Microsoft Visual Studio; we can use __pragma(warning(disable:XXXX))
 143    * and __pragma(warning(push/pop)).
 144    *
 145    * Suppress signed-vs-unsigned comparison, narrowing, and unreachable
 146    * code warnings.
 147    */
 148   #define DIAG_OFF_FLEX \
 149     __pragma(warning(push)) \
 150     __pragma(warning(disable:4127)) \
 151     __pragma(warning(disable:4242)) \
 152     __pragma(warning(disable:4244)) \
 153     __pragma(warning(disable:4702))
 154   #define DIAG_ON_FLEX \
 155     __pragma(warning(pop))
 156
 157   /*
 158    * Suppress narrowing warnings.
 159    */
 160   #define DIAG_OFF_NARROWING \
 161     __pragma(warning(push)) \
 162     __pragma(warning(disable:4242)) \
 163     __pragma(warning(disable:4311))
 164   #define DIAG_ON_NARROWING \
 165     __pragma(warning(pop))
 166
 167   /*
 168    * Suppress deprecation warnings.
 169    */
 170   #define DIAG_OFF_DEPRECATION \
 171     __pragma(warning(push)) \
 172     __pragma(warning(disable:4996))
 173   #define DIAG_ON_DEPRECATION \
 174     __pragma(warning(pop))
 175 #elif PCAP_IS_AT_LEAST_GNUC_VERSION(4,6)
 176   /*
 177    * This is GCC 4.6 or later, or a compiler claiming to be that.
 178    * We can use "GCC diagnostic ignored -Wxxx" (introduced in 4.2)
 179    * and "GCC diagnostic push/pop" (introduced in 4.6).
 180    */
 181   #define DIAG_OFF_FLEX \
 182     PCAP_DO_PRAGMA(GCC diagnostic push) \
 183     PCAP_DO_PRAGMA(GCC diagnostic ignored "-Wsign-compare") \
 184     PCAP_DO_PRAGMA(GCC diagnostic ignored "-Wunused-parameter") \
 185     PCAP_DO_PRAGMA(GCC diagnostic ignored "-Wunreachable-code")
 186   #define DIAG_ON_FLEX \
 187     PCAP_DO_PRAGMA(GCC diagnostic pop)
 188
 189   /*
 190    * GCC currently doesn't issue any narrowing warnings.
 191    */
 192
 193   /*
 194    * Suppress deprecation warnings.
 195    */
 196   #define DIAG_OFF_DEPRECATION \
 197     PCAP_DO_PRAGMA(GCC diagnostic push) \
 198     PCAP_DO_PRAGMA(GCC diagnostic ignored "-Wdeprecated-declarations")
 199   #define DIAG_ON_DEPRECATION \
 200     PCAP_DO_PRAGMA(GCC diagnostic pop)
 201
 202   /*
 203    * Suppress format-truncation= warnings.
 204    * GCC 7.1 had introduced this warning option. Earlier versions (at least
 205    * one particular copy of GCC 4.6.4) treat the request as a warning.
 206    */
 207   #if PCAP_IS_AT_LEAST_GNUC_VERSION(7,1)
 208     #define DIAG_OFF_FORMAT_TRUNCATION \
 209       PCAP_DO_PRAGMA(GCC diagnostic push) \
 210       PCAP_DO_PRAGMA(GCC diagnostic ignored "-Wformat-truncation=")
 211     #define DIAG_ON_FORMAT_TRUNCATION \
 212       PCAP_DO_PRAGMA(GCC diagnostic pop)
 213   #endif
 214 #elif PCAP_IS_AT_LEAST_SUNC_VERSION(5,5)
 215   /*
 216    * Sun C compiler version 5.5 (Studio version 8) and later supports "#pragma
 217    * error_messages()".
 218    */
 219   #define DIAG_OFF_FLEX \
 220     PCAP_DO_PRAGMA(error_messages(off,E_STATEMENT_NOT_REACHED))
 221   #define DIAG_ON_FLEX \
 222     PCAP_DO_PRAGMA(error_messages(default,E_STATEMENT_NOT_REACHED))
 223 #endif
 224
 225 #ifdef YYBYACC
 226   /*
 227    * Berkeley YACC.
 228    *
 229    * It generates a global declaration of yylval, or the appropriately
 230    * prefixed version of yylval, in grammar.h, *even though it's been
 231    * told to generate a pure parser, meaning it doesn't have any global
 232    * variables*.  Bison doesn't do this.
 233    *
 234    * That causes a warning due to the local declaration in the parser
 235    * shadowing the global declaration.
 236    *
 237    * So, if the compiler warns about that, we turn off -Wshadow warnings.
 238    *
 239    * In addition, the generated code may have functions with unreachable
 240    * code, so suppress warnings about those.
 241    */
 242   #if PCAP_IS_AT_LEAST_CLANG_VERSION(2,8)
 243     /*
 244      * This is Clang 2.8 or later (including clang-cl, so test this
 245      * before _MSC_VER); we can use "clang diagnostic ignored -Wxxx".
 246      */
 247     #define DIAG_OFF_BISON_BYACC \
 248       PCAP_DO_PRAGMA(clang diagnostic ignored "-Wshadow") \
 249       PCAP_DO_PRAGMA(clang diagnostic ignored "-Wunreachable-code")
 250   #elif defined(_MSC_VER)
 251     /*
 252      * This is Microsoft Visual Studio; we can use
 253      * __pragma(warning(disable:XXXX)).
 254      */
 255     #define DIAG_OFF_BISON_BYACC \
 256       __pragma(warning(disable:4702))
 257   #elif PCAP_IS_AT_LEAST_GNUC_VERSION(4,6)
 258     /*
 259      * This is GCC 4.6 or later, or a compiler claiming to be that.
 260      * We can use "GCC diagnostic ignored -Wxxx" (introduced in 4.2,
 261      * but it may not actually work very well prior to 4.6).
 262      */
 263     #define DIAG_OFF_BISON_BYACC \
 264       PCAP_DO_PRAGMA(GCC diagnostic ignored "-Wshadow") \
 265       PCAP_DO_PRAGMA(GCC diagnostic ignored "-Wunreachable-code")
 266   #endif
 267 #else
 268   /*
 269    * Bison.
 270    *
 271    * The generated code may have functions with unreachable code and
 272    * switches with only a default case, so suppress warnings about those.
 273    */
 274   #if PCAP_IS_AT_LEAST_CLANG_VERSION(2,8)
 275     /*
 276      * This is Clang 2.8 or later (including clang-cl, so test this
 277      * before _MSC_VER); we can use "clang diagnostic ignored -Wxxx".
 278      */
 279     #define DIAG_OFF_BISON_BYACC \
 280       PCAP_DO_PRAGMA(clang diagnostic ignored "-Wunreachable-code")
 281   #elif defined(_MSC_VER)
 282     /*
 283      * This is Microsoft Visual Studio; we can use
 284      * __pragma(warning(disable:XXXX)).
 285      *
 286      * Suppress some /Wall warnings.
 287      */
 288     #define DIAG_OFF_BISON_BYACC \
 289       __pragma(warning(disable:4065)) \
 290       __pragma(warning(disable:4127)) \
 291       __pragma(warning(disable:4242)) \
 292       __pragma(warning(disable:4244)) \
 293       __pragma(warning(disable:4702))
 294   #elif PCAP_IS_AT_LEAST_GNUC_VERSION(4,6)
 295     /*
 296      * This is GCC 4.6 or later, or a compiler claiming to be that.
 297      * We can use "GCC diagnostic ignored -Wxxx" (introduced in 4.2,
 298      * but it may not actually work very well prior to 4.6).
 299      */
 300     #define DIAG_OFF_BISON_BYACC \
 301       PCAP_DO_PRAGMA(GCC diagnostic ignored "-Wunreachable-code")
 302   #elif PCAP_IS_AT_LEAST_SUNC_VERSION(5,5)
 303     /*
 304      * Same as for DIAG_OFF_FLEX above.
 305      */
 306     #define DIAG_OFF_BISON_BYACC \
 307       PCAP_DO_PRAGMA(error_messages(off,E_STATEMENT_NOT_REACHED))
 308   #endif
 309 #endif
 310
 311 #if PCAP_IS_AT_LEAST_CLANG_VERSION(2,8)
 312   /*
 313    * Clang appears to let you ignore a result without a warning by
 314    * casting the function result to void, so we don't appear to
 315    * need this for Clang.
 316    */
 317 #elif PCAP_IS_AT_LEAST_GNUC_VERSION(4,5)
 318   /*
 319    * GCC warns about unused return values if a function is marked as
 320    * "warn about ignoring this function's return value".
 321    */
 322   #define DIAG_OFF_WARN_UNUSED_RESULT \
 323     PCAP_DO_PRAGMA(GCC diagnostic push) \
 324     PCAP_DO_PRAGMA(GCC diagnostic ignored "-Wunused-result")
 325   #define DIAG_ON_WARN_UNUSED_RESULT \
 326     PCAP_DO_PRAGMA(GCC diagnostic pop)
 327
 328   /*
 329    * GCC does not currently generate any -Wstrict-prototypes warnings that
 330    * would need silencing as is done for Clang above.
 331    */
 332 #endif
 333
 334 /*
 335  * GCC needs this on AIX for longjmp().
 336  */
 337 #if PCAP_IS_AT_LEAST_GNUC_VERSION(5,1)
 338   /*
 339    * Beware that the effect of this builtin is more than just squelching the
 340    * warning! GCC trusts it enough for the process to segfault if the control
 341    * flow reaches the builtin (an infinite empty loop in the same context would
 342    * squelch the warning and ruin the process too, albeit in a different way).
 343    * So please remember to use this very carefully.
 344    */
 345   #define PCAP_UNREACHABLE __builtin_unreachable();
 346 #endif
 347
 348 #ifndef DIAG_OFF_ENUM_SWITCH
 349 #define DIAG_OFF_ENUM_SWITCH
 350 #endif
 351 #ifndef DIAG_ON_ENUM_SWITCH
 352 #define DIAG_ON_ENUM_SWITCH
 353 #endif
 354 #ifndef DIAG_OFF_DEFAULT_ONLY_SWITCH
 355 #define DIAG_OFF_DEFAULT_ONLY_SWITCH
 356 #endif
 357 #ifndef DIAG_ON_DEFAULT_ONLY_SWITCH
 358 #define DIAG_ON_DEFAULT_ONLY_SWITCH
 359 #endif
 360 #ifndef DIAG_OFF_FLEX
 361 #define DIAG_OFF_FLEX
 362 #endif
 363 #ifndef DIAG_ON_FLEX
 364 #define DIAG_ON_FLEX
 365 #endif
 366 #ifndef DIAG_OFF_NARROWING
 367 #define DIAG_OFF_NARROWING
 368 #endif
 369 #ifndef DIAG_ON_NARROWING
 370 #define DIAG_ON_NARROWING
 371 #endif
 372 #ifndef DIAG_OFF_DEPRECATION
 373 #define DIAG_OFF_DEPRECATION
 374 #endif
 375 #ifndef DIAG_ON_DEPRECATION
 376 #define DIAG_ON_DEPRECATION
 377 #endif
 378 #ifndef DIAG_OFF_FORMAT_TRUNCATION
 379 #define DIAG_OFF_FORMAT_TRUNCATION
 380 #endif
 381 #ifndef DIAG_ON_FORMAT_TRUNCATION
 382 #define DIAG_ON_FORMAT_TRUNCATION
 383 #endif
 384 #ifndef DIAG_OFF_BISON_BYACC
 385 #define DIAG_OFF_BISON_BYACC
 386 #endif
 387 #ifndef DIAG_ON_WARN_UNUSED_RESULT
 388 #define DIAG_ON_WARN_UNUSED_RESULT
 389 #endif
 390 #ifndef DIAG_OFF_WARN_UNUSED_RESULT
 391 #define DIAG_OFF_WARN_UNUSED_RESULT
 392 #endif
 393 #ifndef DIAG_OFF_STRICT_PROTOTYPES
 394 #define DIAG_OFF_STRICT_PROTOTYPES
 395 #endif
 396 #ifndef DIAG_ON_STRICT_PROTOTYPES
 397 #define DIAG_ON_STRICT_PROTOTYPES
 398 #endif
 399 #ifndef PCAP_UNREACHABLE
 400 #define PCAP_UNREACHABLE
 401 #endif
 402
 403 #endif /* _diag_control_h */