MdePkg/Include/Library/DebugLib.h

   1 /** @file
   2   Provides services to print debug and assert messages to a debug output device.
   3
   4   The Debug library supports debug print and asserts based on a combination of macros and code.
   5   The debug library can be turned on and off so that the debug code does not increase the size of an image.
   6
   7   Note that a reserved macro named MDEPKG_NDEBUG is introduced for the intention
   8   of size reduction when compiler optimization is disabled. If MDEPKG_NDEBUG is
   9   defined, then debug and assert related macros wrapped by it are the NULL implementations.
  10
  11 Copyright (c) 2006 - 2020, Intel Corporation. All rights reserved.<BR>
  12 SPDX-License-Identifier: BSD-2-Clause-Patent
  13
  14 **/
  15
  16 #ifndef __DEBUG_LIB_H__
  17 #define __DEBUG_LIB_H__
  18
  19 //
  20 // Declare bits for PcdDebugPropertyMask
  21 //
  22 #define DEBUG_PROPERTY_DEBUG_ASSERT_ENABLED       0x01
  23 #define DEBUG_PROPERTY_DEBUG_PRINT_ENABLED        0x02
  24 #define DEBUG_PROPERTY_DEBUG_CODE_ENABLED         0x04
  25 #define DEBUG_PROPERTY_CLEAR_MEMORY_ENABLED       0x08
  26 #define DEBUG_PROPERTY_ASSERT_BREAKPOINT_ENABLED  0x10
  27 #define DEBUG_PROPERTY_ASSERT_DEADLOOP_ENABLED    0x20
  28
  29 //
  30 // Declare bits for PcdDebugPrintErrorLevel and the ErrorLevel parameter of DebugPrint()
  31 //
  32 #define DEBUG_INIT      0x00000001  // Initialization
  33 #define DEBUG_WARN      0x00000002  // Warnings
  34 #define DEBUG_LOAD      0x00000004  // Load events
  35 #define DEBUG_FS        0x00000008  // EFI File system
  36 #define DEBUG_POOL      0x00000010  // Alloc & Free (pool)
  37 #define DEBUG_PAGE      0x00000020  // Alloc & Free (page)
  38 #define DEBUG_INFO      0x00000040  // Informational debug messages
  39 #define DEBUG_DISPATCH  0x00000080  // PEI/DXE/SMM Dispatchers
  40 #define DEBUG_VARIABLE  0x00000100  // Variable
  41 #define DEBUG_BM        0x00000400  // Boot Manager
  42 #define DEBUG_BLKIO     0x00001000  // BlkIo Driver
  43 #define DEBUG_NET       0x00004000  // Network Io Driver
  44 #define DEBUG_UNDI      0x00010000  // UNDI Driver
  45 #define DEBUG_LOADFILE  0x00020000  // LoadFile
  46 #define DEBUG_EVENT     0x00080000  // Event messages
  47 #define DEBUG_GCD       0x00100000  // Global Coherency Database changes
  48 #define DEBUG_CACHE     0x00200000  // Memory range cachability changes
  49 #define DEBUG_VERBOSE   0x00400000  // Detailed debug messages that may
  50                                     // significantly impact boot performance
  51 #define DEBUG_ERROR  0x80000000     // Error
  52
  53 //
  54 // Aliases of debug message mask bits
  55 //
  56 #define EFI_D_INIT      DEBUG_INIT
  57 #define EFI_D_WARN      DEBUG_WARN
  58 #define EFI_D_LOAD      DEBUG_LOAD
  59 #define EFI_D_FS        DEBUG_FS
  60 #define EFI_D_POOL      DEBUG_POOL
  61 #define EFI_D_PAGE      DEBUG_PAGE
  62 #define EFI_D_INFO      DEBUG_INFO
  63 #define EFI_D_DISPATCH  DEBUG_DISPATCH
  64 #define EFI_D_VARIABLE  DEBUG_VARIABLE
  65 #define EFI_D_BM        DEBUG_BM
  66 #define EFI_D_BLKIO     DEBUG_BLKIO
  67 #define EFI_D_NET       DEBUG_NET
  68 #define EFI_D_UNDI      DEBUG_UNDI
  69 #define EFI_D_LOADFILE  DEBUG_LOADFILE
  70 #define EFI_D_EVENT     DEBUG_EVENT
  71 #define EFI_D_VERBOSE   DEBUG_VERBOSE
  72 #define EFI_D_ERROR     DEBUG_ERROR
  73
  74 //
  75 // Source file line number.
  76 // Default is use the to compiler provided __LINE__ macro value. The __LINE__
  77 // mapping can be overriden by predefining DEBUG_LINE_NUMBER
  78 //
  79 // Defining DEBUG_LINE_NUMBER to a fixed value is useful when comparing builds
  80 // across source code formatting changes that may add/remove lines in a source
  81 // file.
  82 //
  83 #ifdef DEBUG_LINE_NUMBER
  84 #else
  85 #define DEBUG_LINE_NUMBER  __LINE__
  86 #endif
  87
  88 /**
  89   Macro that converts a Boolean expression to a Null-terminated ASCII string.
  90
  91   The default is to use the C pre-processor stringizing operator '#' to add
  92   quotes around the C expression. If DEBUG_EXPRESSION_STRING_VALUE is defined
  93   then the C expression is converted to the fixed string value.
  94
  95   Defining DEBUG_EXPRESSION_STRING_VALUE to a fixed value is useful when
  96   comparing builds across source code formatting changes that may make
  97   changes to spaces or parenthesis in a Boolean expression.
  98
  99   @param  Expression  Boolean expression.
 100
 101 **/
 102
 103 #ifdef DEBUG_EXPRESSION_STRING_VALUE
 104 #define DEBUG_EXPRESSION_STRING(Expression)  DEBUG_EXPRESSION_STRING_VALUE
 105 #else
 106 #define DEBUG_EXPRESSION_STRING(Expression)  #Expression
 107 #endif
 108
 109 /**
 110   Prints a debug message to the debug output device if the specified error level is enabled.
 111
 112   If any bit in ErrorLevel is also set in DebugPrintErrorLevelLib function
 113   GetDebugPrintErrorLevel (), then print the message specified by Format and the
 114   associated variable argument list to the debug output device.
 115
 116   If Format is NULL, then ASSERT().
 117
 118   @param  ErrorLevel  The error level of the debug message.
 119   @param  Format      The format string for the debug message to print.
 120   @param  ...         The variable argument list whose contents are accessed
 121                       based on the format string specified by Format.
 122
 123 **/
 124 VOID
 125 EFIAPI
 126 DebugPrint (
 127   IN  UINTN        ErrorLevel,
 128   IN  CONST CHAR8  *Format,
 129   ...
 130   );
 131
 132 /**
 133   Prints a debug message to the debug output device if the specified
 134   error level is enabled.
 135
 136   If any bit in ErrorLevel is also set in DebugPrintErrorLevelLib function
 137   GetDebugPrintErrorLevel (), then print the message specified by Format and
 138   the associated variable argument list to the debug output device.
 139
 140   If Format is NULL, then ASSERT().
 141
 142   @param  ErrorLevel    The error level of the debug message.
 143   @param  Format        Format string for the debug message to print.
 144   @param  VaListMarker  VA_LIST marker for the variable argument list.
 145
 146 **/
 147 VOID
 148 EFIAPI
 149 DebugVPrint (
 150   IN  UINTN        ErrorLevel,
 151   IN  CONST CHAR8  *Format,
 152   IN  VA_LIST      VaListMarker
 153   );
 154
 155 /**
 156   Prints a debug message to the debug output device if the specified
 157   error level is enabled.
 158   This function use BASE_LIST which would provide a more compatible
 159   service than VA_LIST.
 160
 161   If any bit in ErrorLevel is also set in DebugPrintErrorLevelLib function
 162   GetDebugPrintErrorLevel (), then print the message specified by Format and
 163   the associated variable argument list to the debug output device.
 164
 165   If Format is NULL, then ASSERT().
 166
 167   @param  ErrorLevel      The error level of the debug message.
 168   @param  Format          Format string for the debug message to print.
 169   @param  BaseListMarker  BASE_LIST marker for the variable argument list.
 170
 171 **/
 172 VOID
 173 EFIAPI
 174 DebugBPrint (
 175   IN  UINTN        ErrorLevel,
 176   IN  CONST CHAR8  *Format,
 177   IN  BASE_LIST    BaseListMarker
 178   );
 179
 180 /**
 181   Prints an assert message containing a filename, line number, and description.
 182   This may be followed by a breakpoint or a dead loop.
 183
 184   Print a message of the form "ASSERT <FileName>(<LineNumber>): <Description>\n"
 185   to the debug output device.  If DEBUG_PROPERTY_ASSERT_BREAKPOINT_ENABLED bit of
 186   PcdDebugProperyMask is set then CpuBreakpoint() is called. Otherwise, if
 187   DEBUG_PROPERTY_ASSERT_DEADLOOP_ENABLED bit of PcdDebugProperyMask is set then
 188   CpuDeadLoop() is called.  If neither of these bits are set, then this function
 189   returns immediately after the message is printed to the debug output device.
 190   DebugAssert() must actively prevent recursion.  If DebugAssert() is called while
 191   processing another DebugAssert(), then DebugAssert() must return immediately.
 192
 193   If FileName is NULL, then a <FileName> string of "(NULL) Filename" is printed.
 194   If Description is NULL, then a <Description> string of "(NULL) Description" is printed.
 195
 196   @param  FileName     The pointer to the name of the source file that generated the assert condition.
 197   @param  LineNumber   The line number in the source file that generated the assert condition
 198   @param  Description  The pointer to the description of the assert condition.
 199
 200 **/
 201 VOID
 202 EFIAPI
 203 DebugAssert (
 204   IN CONST CHAR8  *FileName,
 205   IN UINTN        LineNumber,
 206   IN CONST CHAR8  *Description
 207   );
 208
 209 /**
 210   Fills a target buffer with PcdDebugClearMemoryValue, and returns the target buffer.
 211
 212   This function fills Length bytes of Buffer with the value specified by
 213   PcdDebugClearMemoryValue, and returns Buffer.
 214
 215   If Buffer is NULL, then ASSERT().
 216   If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
 217
 218   @param   Buffer  The pointer to the target buffer to be filled with PcdDebugClearMemoryValue.
 219   @param   Length  The number of bytes in Buffer to fill with zeros PcdDebugClearMemoryValue.
 220
 221   @return  Buffer  The pointer to the target buffer filled with PcdDebugClearMemoryValue.
 222
 223 **/
 224 VOID *
 225 EFIAPI
 226 DebugClearMemory (
 227   OUT VOID  *Buffer,
 228   IN UINTN  Length
 229   );
 230
 231 /**
 232   Returns TRUE if ASSERT() macros are enabled.
 233
 234   This function returns TRUE if the DEBUG_PROPERTY_DEBUG_ASSERT_ENABLED bit of
 235   PcdDebugProperyMask is set.  Otherwise, FALSE is returned.
 236
 237   @retval  TRUE    The DEBUG_PROPERTY_DEBUG_ASSERT_ENABLED bit of PcdDebugProperyMask is set.
 238   @retval  FALSE   The DEBUG_PROPERTY_DEBUG_ASSERT_ENABLED bit of PcdDebugProperyMask is clear.
 239
 240 **/
 241 BOOLEAN
 242 EFIAPI
 243 DebugAssertEnabled (
 244   VOID
 245   );
 246
 247 /**
 248   Returns TRUE if DEBUG() macros are enabled.
 249
 250   This function returns TRUE if the DEBUG_PROPERTY_DEBUG_PRINT_ENABLED bit of
 251   PcdDebugProperyMask is set.  Otherwise, FALSE is returned.
 252
 253   @retval  TRUE    The DEBUG_PROPERTY_DEBUG_PRINT_ENABLED bit of PcdDebugProperyMask is set.
 254   @retval  FALSE   The DEBUG_PROPERTY_DEBUG_PRINT_ENABLED bit of PcdDebugProperyMask is clear.
 255
 256 **/
 257 BOOLEAN
 258 EFIAPI
 259 DebugPrintEnabled (
 260   VOID
 261   );
 262
 263 /**
 264   Returns TRUE if DEBUG_CODE() macros are enabled.
 265
 266   This function returns TRUE if the DEBUG_PROPERTY_DEBUG_CODE_ENABLED bit of
 267   PcdDebugProperyMask is set.  Otherwise, FALSE is returned.
 268
 269   @retval  TRUE    The DEBUG_PROPERTY_DEBUG_CODE_ENABLED bit of PcdDebugProperyMask is set.
 270   @retval  FALSE   The DEBUG_PROPERTY_DEBUG_CODE_ENABLED bit of PcdDebugProperyMask is clear.
 271
 272 **/
 273 BOOLEAN
 274 EFIAPI
 275 DebugCodeEnabled (
 276   VOID
 277   );
 278
 279 /**
 280   Returns TRUE if DEBUG_CLEAR_MEMORY() macro is enabled.
 281
 282   This function returns TRUE if the DEBUG_PROPERTY_CLEAR_MEMORY_ENABLED bit of
 283   PcdDebugProperyMask is set.  Otherwise, FALSE is returned.
 284
 285   @retval  TRUE    The DEBUG_PROPERTY_CLEAR_MEMORY_ENABLED bit of PcdDebugProperyMask is set.
 286   @retval  FALSE   The DEBUG_PROPERTY_CLEAR_MEMORY_ENABLED bit of PcdDebugProperyMask is clear.
 287
 288 **/
 289 BOOLEAN
 290 EFIAPI
 291 DebugClearMemoryEnabled (
 292   VOID
 293   );
 294
 295 /**
 296   Returns TRUE if any one of the bit is set both in ErrorLevel and PcdFixedDebugPrintErrorLevel.
 297
 298   This function compares the bit mask of ErrorLevel and PcdFixedDebugPrintErrorLevel.
 299
 300   @retval  TRUE    Current ErrorLevel is supported.
 301   @retval  FALSE   Current ErrorLevel is not supported.
 302
 303 **/
 304 BOOLEAN
 305 EFIAPI
 306 DebugPrintLevelEnabled (
 307   IN  CONST UINTN  ErrorLevel
 308   );
 309
 310 /**
 311   Internal worker macro that calls DebugAssert().
 312
 313   This macro calls DebugAssert(), passing in the filename, line number, and an
 314   expression that evaluated to FALSE.
 315
 316   @param  Expression  Boolean expression that evaluated to FALSE
 317
 318 **/
 319 #if defined (EDKII_UNIT_TEST_FRAMEWORK_ENABLED)
 320
 321 /**
 322   Unit test library replacement for DebugAssert() in DebugLib.
 323
 324   If FileName is NULL, then a <FileName> string of "(NULL) Filename" is printed.
 325   If Description is NULL, then a <Description> string of "(NULL) Description" is printed.
 326
 327   @param  FileName     The pointer to the name of the source file that generated the assert condition.
 328   @param  LineNumber   The line number in the source file that generated the assert condition
 329   @param  Description  The pointer to the description of the assert condition.
 330
 331 **/
 332 VOID
 333 EFIAPI
 334 UnitTestDebugAssert (
 335   IN CONST CHAR8  *FileName,
 336   IN UINTN        LineNumber,
 337   IN CONST CHAR8  *Description
 338   );
 339
 340   #if defined (__clang__) && defined (__FILE_NAME__)
 341 #define _ASSERT(Expression)  UnitTestDebugAssert (__FILE_NAME__, DEBUG_LINE_NUMBER, DEBUG_EXPRESSION_STRING (Expression))
 342   #else
 343 #define _ASSERT(Expression)  UnitTestDebugAssert (__FILE__, DEBUG_LINE_NUMBER, DEBUG_EXPRESSION_STRING (Expression))
 344   #endif
 345 #else
 346   #if defined (__clang__) && defined (__FILE_NAME__)
 347 #define _ASSERT(Expression)  DebugAssert (__FILE_NAME__, DEBUG_LINE_NUMBER, DEBUG_EXPRESSION_STRING (Expression))
 348   #else
 349 #define _ASSERT(Expression)  DebugAssert (__FILE__, DEBUG_LINE_NUMBER, DEBUG_EXPRESSION_STRING (Expression))
 350   #endif
 351 #endif
 352
 353 /**
 354   Internal worker macro that calls DebugPrint().
 355
 356   This macro calls DebugPrint() passing in the debug error level, a format
 357   string, and a variable argument list.
 358   __VA_ARGS__ is not supported by EBC compiler, Microsoft Visual Studio .NET 2003
 359   and Microsoft Windows Server 2003 Driver Development Kit (Microsoft WINDDK) version 3790.1830.
 360
 361   @param  Expression  Expression containing an error level, a format string,
 362                       and a variable argument list based on the format string.
 363
 364 **/
 365
 366 #if !defined (MDE_CPU_EBC) && (!defined (_MSC_VER) || _MSC_VER > 1400)
 367 #define _DEBUG_PRINT(PrintLevel, ...)              \
 368     do {                                             \
 369       if (DebugPrintLevelEnabled (PrintLevel)) {     \
 370         DebugPrint (PrintLevel, ##__VA_ARGS__);      \
 371       }                                              \
 372     } while (FALSE)
 373 #define _DEBUG(Expression)  _DEBUG_PRINT Expression
 374 #else
 375 #define _DEBUG(Expression)  DebugPrint Expression
 376 #endif
 377
 378 /**
 379   Macro that calls DebugAssert() if an expression evaluates to FALSE.
 380
 381   If MDEPKG_NDEBUG is not defined and the DEBUG_PROPERTY_DEBUG_ASSERT_ENABLED
 382   bit of PcdDebugProperyMask is set, then this macro evaluates the Boolean
 383   expression specified by Expression.  If Expression evaluates to FALSE, then
 384   DebugAssert() is called passing in the source filename, source line number,
 385   and Expression.
 386
 387   @param  Expression  Boolean expression.
 388
 389 **/
 390 #if !defined (MDEPKG_NDEBUG)
 391 #define ASSERT(Expression)        \
 392     do {                            \
 393       if (DebugAssertEnabled ()) {  \
 394         if (!(Expression)) {        \
 395           _ASSERT (Expression);     \
 396           ANALYZER_UNREACHABLE ();  \
 397         }                           \
 398       }                             \
 399     } while (FALSE)
 400 #else
 401 #define ASSERT(Expression)
 402 #endif
 403
 404 /**
 405   Macro that calls DebugPrint().
 406
 407   If MDEPKG_NDEBUG is not defined and the DEBUG_PROPERTY_DEBUG_PRINT_ENABLED
 408   bit of PcdDebugProperyMask is set, then this macro passes Expression to
 409   DebugPrint().
 410
 411   @param  Expression  Expression containing an error level, a format string,
 412                       and a variable argument list based on the format string.
 413
 414
 415 **/
 416 #if !defined (MDEPKG_NDEBUG)
 417 #define DEBUG(Expression)        \
 418     do {                           \
 419       if (DebugPrintEnabled ()) {  \
 420         _DEBUG (Expression);       \
 421       }                            \
 422     } while (FALSE)
 423 #else
 424 #define DEBUG(Expression)
 425 #endif
 426
 427 /**
 428   Macro that calls DebugAssert() if an EFI_STATUS evaluates to an error code.
 429
 430   If MDEPKG_NDEBUG is not defined and the DEBUG_PROPERTY_DEBUG_ASSERT_ENABLED
 431   bit of PcdDebugProperyMask is set, then this macro evaluates the EFI_STATUS
 432   value specified by StatusParameter.  If StatusParameter is an error code,
 433   then DebugAssert() is called passing in the source filename, source line
 434   number, and StatusParameter.
 435
 436   @param  StatusParameter  EFI_STATUS value to evaluate.
 437
 438 **/
 439 #if !defined (MDEPKG_NDEBUG)
 440 #define ASSERT_EFI_ERROR(StatusParameter)                                              \
 441     do {                                                                                 \
 442       if (DebugAssertEnabled ()) {                                                       \
 443         if (EFI_ERROR (StatusParameter)) {                                               \
 444           DEBUG ((DEBUG_ERROR, "\nASSERT_EFI_ERROR (Status = %r)\n", StatusParameter));  \
 445           _ASSERT (!EFI_ERROR (StatusParameter));                                        \
 446         }                                                                                \
 447       }                                                                                  \
 448     } while (FALSE)
 449 #else
 450 #define ASSERT_EFI_ERROR(StatusParameter)
 451 #endif
 452
 453 /**
 454   Macro that calls DebugAssert() if a RETURN_STATUS evaluates to an error code.
 455
 456   If MDEPKG_NDEBUG is not defined and the DEBUG_PROPERTY_DEBUG_ASSERT_ENABLED
 457   bit of PcdDebugProperyMask is set, then this macro evaluates the
 458   RETURN_STATUS value specified by StatusParameter.  If StatusParameter is an
 459   error code, then DebugAssert() is called passing in the source filename,
 460   source line number, and StatusParameter.
 461
 462   @param  StatusParameter  RETURN_STATUS value to evaluate.
 463
 464 **/
 465 #if !defined (MDEPKG_NDEBUG)
 466 #define ASSERT_RETURN_ERROR(StatusParameter)                          \
 467     do {                                                                \
 468       if (DebugAssertEnabled ()) {                                      \
 469         if (RETURN_ERROR (StatusParameter)) {                           \
 470           DEBUG ((DEBUG_ERROR, "\nASSERT_RETURN_ERROR (Status = %r)\n", \
 471             StatusParameter));                                          \
 472           _ASSERT (!RETURN_ERROR (StatusParameter));                    \
 473         }                                                               \
 474       }                                                                 \
 475     } while (FALSE)
 476 #else
 477 #define ASSERT_RETURN_ERROR(StatusParameter)
 478 #endif
 479
 480 /**
 481   Macro that calls DebugAssert() if a protocol is already installed in the
 482   handle database.
 483
 484   If MDEPKG_NDEBUG is defined or the DEBUG_PROPERTY_DEBUG_ASSERT_ENABLED bit
 485   of PcdDebugProperyMask is clear, then return.
 486
 487   If Handle is NULL, then a check is made to see if the protocol specified by Guid
 488   is present on any handle in the handle database.  If Handle is not NULL, then
 489   a check is made to see if the protocol specified by Guid is present on the
 490   handle specified by Handle.  If the check finds the protocol, then DebugAssert()
 491   is called passing in the source filename, source line number, and Guid.
 492
 493   If Guid is NULL, then ASSERT().
 494
 495   @param  Handle  The handle to check for the protocol.  This is an optional
 496                   parameter that may be NULL.  If it is NULL, then the entire
 497                   handle database is searched.
 498
 499   @param  Guid    The pointer to a protocol GUID.
 500
 501 **/
 502 #if !defined (MDEPKG_NDEBUG)
 503 #define ASSERT_PROTOCOL_ALREADY_INSTALLED(Handle, Guid)                               \
 504     do {                                                                                \
 505       if (DebugAssertEnabled ()) {                                                      \
 506         VOID  *Instance;                                                                \
 507         ASSERT (Guid != NULL);                                                          \
 508         if (Handle == NULL) {                                                           \
 509           if (!EFI_ERROR (gBS->LocateProtocol ((EFI_GUID *)Guid, NULL, &Instance))) {   \
 510             _ASSERT (Guid already installed in database);                               \
 511           }                                                                             \
 512         } else {                                                                        \
 513           if (!EFI_ERROR (gBS->HandleProtocol (Handle, (EFI_GUID *)Guid, &Instance))) { \
 514             _ASSERT (Guid already installed on Handle);                                 \
 515           }                                                                             \
 516         }                                                                               \
 517       }                                                                                 \
 518     } while (FALSE)
 519 #else
 520 #define ASSERT_PROTOCOL_ALREADY_INSTALLED(Handle, Guid)
 521 #endif
 522
 523 /**
 524   Macro that marks the beginning of debug source code.
 525
 526   If the DEBUG_PROPERTY_DEBUG_CODE_ENABLED bit of PcdDebugProperyMask is set,
 527   then this macro marks the beginning of source code that is included in a module.
 528   Otherwise, the source lines between DEBUG_CODE_BEGIN() and DEBUG_CODE_END()
 529   are not included in a module.
 530
 531 **/
 532 #define DEBUG_CODE_BEGIN()  do { if (DebugCodeEnabled ()) { UINT8  __DebugCodeLocal
 533
 534 /**
 535   The macro that marks the end of debug source code.
 536
 537   If the DEBUG_PROPERTY_DEBUG_CODE_ENABLED bit of PcdDebugProperyMask is set,
 538   then this macro marks the end of source code that is included in a module.
 539   Otherwise, the source lines between DEBUG_CODE_BEGIN() and DEBUG_CODE_END()
 540   are not included in a module.
 541
 542 **/
 543 #define DEBUG_CODE_END()  __DebugCodeLocal = 0; __DebugCodeLocal++; } } while (FALSE)
 544
 545 /**
 546   The macro that declares a section of debug source code.
 547
 548   If the DEBUG_PROPERTY_DEBUG_CODE_ENABLED bit of PcdDebugProperyMask is set,
 549   then the source code specified by Expression is included in a module.
 550   Otherwise, the source specified by Expression is not included in a module.
 551
 552 **/
 553 #define DEBUG_CODE(Expression)  \
 554   DEBUG_CODE_BEGIN ();          \
 555   Expression                    \
 556   DEBUG_CODE_END ()
 557
 558 /**
 559   The macro that calls DebugClearMemory() to clear a buffer to a default value.
 560
 561   If the DEBUG_PROPERTY_CLEAR_MEMORY_ENABLED bit of PcdDebugProperyMask is set,
 562   then this macro calls DebugClearMemory() passing in Address and Length.
 563
 564   @param  Address  The pointer to a buffer.
 565   @param  Length   The number of bytes in the buffer to set.
 566
 567 **/
 568 #define DEBUG_CLEAR_MEMORY(Address, Length)  \
 569   do {                                       \
 570     if (DebugClearMemoryEnabled ()) {        \
 571       DebugClearMemory (Address, Length);    \
 572     }                                        \
 573   } while (FALSE)
 574
 575 /**
 576   Macro that calls DebugAssert() if the containing record does not have a
 577   matching signature.  If the signatures matches, then a pointer to the data
 578   structure that contains a specified field of that data structure is returned.
 579   This is a lightweight method hide information by placing a public data
 580   structure inside a larger private data structure and using a pointer to the
 581   public data structure to retrieve a pointer to the private data structure.
 582
 583   If MDEPKG_NDEBUG is defined or the DEBUG_PROPERTY_DEBUG_ASSERT_ENABLED bit
 584   of PcdDebugProperyMask is clear, then this macro computes the offset, in bytes,
 585   of the field specified by Field from the beginning of the data structure specified
 586   by TYPE.  This offset is subtracted from Record, and is used to return a pointer
 587   to a data structure of the type specified by TYPE.
 588
 589   If MDEPKG_NDEBUG is not defined and the DEBUG_PROPERTY_DEBUG_ASSERT_ENABLED bit
 590   of PcdDebugProperyMask is set, then this macro computes the offset, in bytes,
 591   of field specified by Field from the beginning of the data structure specified
 592   by TYPE.  This offset is subtracted from Record, and is used to compute a pointer
 593   to a data structure of the type specified by TYPE.  The Signature field of the
 594   data structure specified by TYPE is compared to TestSignature.  If the signatures
 595   match, then a pointer to the pointer to a data structure of the type specified by
 596   TYPE is returned.  If the signatures do not match, then DebugAssert() is called
 597   with a description of "CR has a bad signature" and Record is returned.
 598
 599   If the data type specified by TYPE does not contain the field specified by Field,
 600   then the module will not compile.
 601
 602   If TYPE does not contain a field called Signature, then the module will not
 603   compile.
 604
 605   @param  Record         The pointer to the field specified by Field within a data
 606                          structure of type TYPE.
 607
 608   @param  TYPE           The name of the data structure type to return  This
 609                          data structure must contain the field specified by Field.
 610
 611   @param  Field          The name of the field in the data structure specified
 612                          by TYPE to which Record points.
 613
 614   @param  TestSignature  The 32-bit signature value to match.
 615
 616 **/
 617 #if !defined (MDEPKG_NDEBUG)
 618 #define CR(Record, TYPE, Field, TestSignature)                                              \
 619     (DebugAssertEnabled () && (BASE_CR (Record, TYPE, Field)->Signature != TestSignature)) ?  \
 620     (TYPE *) (_ASSERT (CR has Bad Signature), Record) :                                       \
 621     BASE_CR (Record, TYPE, Field)
 622 #else
 623 #define CR(Record, TYPE, Field, TestSignature)                                              \
 624     BASE_CR (Record, TYPE, Field)
 625 #endif
 626
 627 #endif