include/wvassert.h

   1 /* -*- Mode: C++ -*-
   2  * Worldvisions Weaver Software:
   3  *   Copyright (C) 2005 Net Integration Technologies, Inc.
   4  *
   5  * Helper classes and functions to add more information to WvCrashes.
   6  */
   7 #ifndef __WVASSERT_H
   8 #define __WVASSERT_H
   9
  10 #include <assert.h>
  11
  12 #include "wvcrash.h"
  13 #include "wvstring.h"
  14
  15 // WvCrash allows you to print a programme's last will and testament.
  16 // That is, a little note about what it was hoping to do before it
  17 // died.
  18 //
  19 // This helper class lets you write a will, and when it gets
  20 // destroyed, it will restore the old will from before.  This lets you
  21 // safely nest them.
  22 class WvCrashWill
  23 {
  24 public:
  25     // Leave a will behind.
  26     WvCrashWill(const char *will);
  27     WvCrashWill(WVSTRING_FORMAT_DECL);
  28
  29     // Restore the will that was there before you created this object.
  30     ~WvCrashWill();
  31
  32     // Rewrite the will you're leaving behind.
  33     void rewrite(const char *will);
  34     void rewrite(WVSTRING_FORMAT_DECL);
  35 private:
  36     WvString old_will;
  37 };
  38
  39 #if !defined(__GLIBC__)
  40
  41 # define wvassert(expr, args...)            assert(expr)
  42 # define wvassert_perror(errnum)            perror(errnum)
  43
  44 #elif defined(NDEBUG)
  45
  46 # define wvassert(expr, args...)        (__ASSERT_VOID_CAST (0))
  47 # define wvassert_perror(errnum)        (__ASSERT_VOID_CAST (0))
  48
  49 #else // Not NDEBUG
  50
  51 static inline void __wvcrash_leave_will()
  52 {
  53 }
  54
  55 static inline void __wvcrash_leave_will(const char *will)
  56 {
  57     wvcrash_leave_will(will);
  58 }
  59
  60 static inline void __wvcrash_leave_will(WVSTRING_FORMAT_DECL)
  61 {
  62     wvcrash_leave_will(WvFastString(WVSTRING_FORMAT_CALL));
  63 }
  64
  65 // Use this function instead of assert().  You may also leave parameters
  66 // at the end, which allow you to log messages.  For instance:
  67 //
  68 // wvassert(a == b, "a: '%s'\n b: '%s'", a, b);
  69 # define wvassert(expr, args...) \
  70   (__ASSERT_VOID_CAST ((expr) ? 0 :                                           \
  71                        (__wvcrash_leave_will (args),                          \
  72                         (__assert_fail (__STRING(expr), __FILE__, __LINE__,   \
  73                                         __ASSERT_FUNCTION), 0))))
  74
  75 // Use this function instead of assert_perror().  You may also leave
  76 // parameters at the end, which allow you to log messages.  For instance:
  77 //
  78 // wvassert(errno, "Error trying to read file: '%s'", filename);
  79 #  define wvassert_perror(errnum, args...) \
  80   (__ASSERT_VOID_CAST (!(errnum) ? 0 :                                        \
  81                        (__wvcrash_leave_will (args),                          \
  82                         (__assert_perror_fail ((errnum), __FILE__, __LINE__,  \
  83                                                __ASSERT_FUNCTION), 0))))
  84
  85 #endif // NDEBUG
  86
  87 #endif // WVASSERT_H