src/include/assert.h

   1 #ifndef _ASSERT_H
   2 #define _ASSERT_H
   3
   4 /** @file
   5  *
   6  * Assertions
   7  *
   8  * This file provides two assertion macros: assert() (for run-time
   9  * assertions) and linker_assert() (for link-time assertions).
  10  *
  11  */
  12
  13 FILE_LICENCE ( GPL2_OR_LATER );
  14
  15 #ifdef NDEBUG
  16 #define ASSERTING 0
  17 #else
  18 #define ASSERTING 1
  19 #endif
  20
  21 /** printf() for assertions
  22  *
  23  * This function exists so that the assert() macro can expand to
  24  * printf() calls without dragging the printf() prototype into scope.
  25  *
  26  * As far as the compiler is concerned, assert_printf() and printf() are
  27  * completely unrelated calls; it's only at the assembly stage that
  28  * references to the assert_printf symbol are collapsed into references
  29  * to the printf symbol.
  30  */
  31 extern int __attribute__ (( format ( printf, 1, 2 ) ))
  32 assert_printf ( const char *fmt, ... ) asm ( "printf" );
  33
  34 /**
  35  * Assert a condition at run-time.
  36  *
  37  * If the condition is not true, a debug message will be printed.
  38  * Assertions only take effect in debug-enabled builds (see DBG()).
  39  *
  40  * @todo Make an assertion failure abort the program
  41  *
  42  */
  43 #define assert( condition )                                                  \
  44         do {                                                                 \
  45                 if ( ASSERTING && ! (condition) ) {                          \
  46                         assert_printf ( "assert(%s) failed at %s line %d\n", \
  47                                         #condition, __FILE__, __LINE__ );    \
  48                 }                                                            \
  49         } while ( 0 )
  50
  51 /**
  52  * Assert a condition at link-time.
  53  *
  54  * If the condition is not true, the link will fail with an unresolved
  55  * symbol (error_symbol).
  56  *
  57  * This macro is gPXE-specific.  Do not use this macro in code
  58  * intended to be portable.
  59  *
  60  */
  61 #define linker_assert( condition, error_symbol )        \
  62         if ( ! (condition) ) {                          \
  63                 extern void error_symbol ( void );      \
  64                 error_symbol();                         \
  65         }
  66
  67 #endif /* _ASSERT_H */