my_dbug.h

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/* Copyright (c) 2000, 2024, Oracle and/or its affiliates.
 
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License, version 2.0,
   as published by the Free Software Foundation.
 
   This program is designed to work with certain software (including
   but not limited to OpenSSL) that is licensed under separate terms,
   as designated in a particular file or component or in included license
   documentation.  The authors of MySQL hereby grant you an additional
   permission to link the program and your derivative works with the
   separately licensed software that they have either included with
   the program or referenced in the documentation.
 
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License, version 2.0, for more details.
 
   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA */
 
#ifndef MY_DBUG_INCLUDED
#define MY_DBUG_INCLUDED
 
/**
  @file include/my_dbug.h
*/
 
#ifdef MY_MSCRT_DEBUG
#include <crtdbg.h>
#endif
#include <stdlib.h>
 
#include "my_compiler.h"
 
#include <string.h>
 
#if !defined(NDEBUG)
#include <assert.h>  // IWYU pragma: keep
#include <stdio.h>
#endif
 
/**
  Calls our own implementation of abort, if specified, or std's abort().
 */
[[noreturn]] void my_abort();
/**
  Sets a new function to be called on my_abort().
 
  @param new_my_abort_func pointer to a new my_abort function. It can't be
  [[noreturn]] as pointers to methods can't have attributes.
 */
void set_my_abort(void (*new_my_abort_func)());
 
#if !defined(NDEBUG)
 
struct _db_stack_frame_ {
  const char *func;   /* function name of the previous stack frame       */
  int func_len;       /* how much to print from func */
  const char *file;   /* filename of the function of previous frame      */
  unsigned int level; /* this nesting level, highest bit enables tracing */
  struct _db_stack_frame_ *prev; /* pointer to the previous frame */
};
 
struct CODE_STATE;
 
extern int _db_keyword_(struct CODE_STATE *, const char *, int);
extern int _db_explain_(struct CODE_STATE *cs, char *buf, size_t len);
extern int _db_explain_init_(char *buf, size_t len);
extern int _db_is_pushed_(void);
extern void _db_process_(const char *name);
extern void _db_push_(const char *control);
extern void _db_pop_(void);
extern void _db_set_(const char *control);
extern void _db_set_init_(const char *control);
extern void _db_enter_(const char *_func_, int func_len, const char *_file_,
                       unsigned int _line_,
                       struct _db_stack_frame_ *_stack_frame_);
extern void _db_return_(unsigned int _line_,
                        struct _db_stack_frame_ *_stack_frame_);
extern void _db_pargs_(unsigned int _line_, const char *keyword);
extern int _db_enabled_();
extern void _db_doprnt_(const char *format, ...)
    MY_ATTRIBUTE((format(printf, 1, 2)));
extern void _db_dump_(unsigned int _line_, const char *keyword,
                      const unsigned char *memory, size_t length);
extern void _db_end_(void);
extern void _db_lock_file_(void);
extern void _db_unlock_file_(void);
extern FILE *_db_fp_(void);
extern void _db_flush_();
 
#ifdef __cplusplus
 
#if defined(__GNUC__)
// GCC, Clang, and compatible compilers.
#define DBUG_PRETTY_FUNCTION __PRETTY_FUNCTION__
#elif defined(__FUNCSIG__)
// For MSVC; skips the __cdecl. (__PRETTY_FUNCTION__ in GCC is not a
// preprocessor constant, but __FUNCSIG__ in MSVC is.)
#define DBUG_PRETTY_FUNCTION strchr(__FUNCSIG__, ' ') + 1
#else
// Standard C++; does not include the class name.
#define DBUG_PRETTY_FUNCTION __func__
#endif
 
/**
  A RAII helper to do DBUG_ENTER / DBUG_RETURN for you automatically. Use like
  this:
 
   int foo() {
     DBUG_TRACE;
     return 42;
   }
 */
class AutoDebugTrace {
 public:
  AutoDebugTrace(const char *function, const char *filename, int line) {
    // Remove the return type, if it's there.
    const char *begin = strchr(function, ' ');
    if (begin != nullptr) {
      function = begin + 1;
    }
 
    // Cut it off at the first parenthesis; the argument list is
    // often too long to be interesting.
    const char *end = strchr(function, '(');
 
    if (end == nullptr) {
      _db_enter_(function, static_cast<int>(strlen(function)), filename, line,
                 &m_stack_frame);
    } else {
      _db_enter_(function, static_cast<int>(end - function), filename, line,
                 &m_stack_frame);
    }
  }
 
  ~AutoDebugTrace() { _db_return_(0, &m_stack_frame); }
 
 private:
  _db_stack_frame_ m_stack_frame;
};
 
#define DBUG_TRACE \
  const AutoDebugTrace _db_trace(DBUG_PRETTY_FUNCTION, __FILE__, __LINE__)
 
#endif
 
#define DBUG_ENTER(a)                       \
  struct _db_stack_frame_ _db_stack_frame_; \
  _db_enter_(a, ::strlen(a), __FILE__, __LINE__, &_db_stack_frame_)
 
#define DBUG_RETURN(a1)                       \
  do {                                        \
    _db_return_(__LINE__, &_db_stack_frame_); \
    return (a1);                              \
  } while (0)
#define DBUG_VOID_RETURN                      \
  do {                                        \
    _db_return_(__LINE__, &_db_stack_frame_); \
    return;                                   \
  } while (0)
#define DBUG_EXECUTE(keyword, a1)        \
  do {                                   \
    if (_db_keyword_(0, (keyword), 0)) { \
      a1                                 \
    }                                    \
  } while (0)
#define DBUG_EXECUTE_IF(keyword, a1)     \
  do {                                   \
    if (_db_keyword_(0, (keyword), 1)) { \
      a1                                 \
    }                                    \
  } while (0)
#define DBUG_EVALUATE(keyword, a1, a2) \
  (_db_keyword_(0, (keyword), 0) ? (a1) : (a2))
#define DBUG_EVALUATE_IF(keyword, a1, a2) \
  (_db_keyword_(0, (keyword), 1) ? (a1) : (a2))
#define DBUG_PRINT(keyword, arglist) \
  do {                               \
    _db_pargs_(__LINE__, keyword);   \
    if (_db_enabled_()) {            \
      _db_doprnt_ arglist;           \
    }                                \
  } while (0)
 
#define DBUG_PUSH(a1) _db_push_(a1)
#define DBUG_POP() _db_pop_()
#define DBUG_SET(a1) _db_set_(a1)
#define DBUG_SET_INITIAL(a1) _db_set_init_(a1)
#define DBUG_PROCESS(a1) _db_process_(a1)
#define DBUG_FILE _db_fp_()
#define DBUG_DUMP(keyword, a1, a2) _db_dump_(__LINE__, keyword, a1, a2)
#define DBUG_END() _db_end_()
#define DBUG_LOCK_FILE _db_lock_file_()
#define DBUG_UNLOCK_FILE _db_unlock_file_()
#define DBUG_EXPLAIN(buf, len) _db_explain_(0, (buf), (len))
#define DBUG_EXPLAIN_INITIAL(buf, len) _db_explain_init_((buf), (len))
#ifndef _WIN32
#define DBUG_ABORT() (_db_flush_(), my_abort())
#define DBUG_EXIT() (_db_flush_(), exit(2))
#else
#include <crtdbg.h>
 
#define DBUG_ABORT()                                                     \
  (_db_flush_(), (void)_CrtSetReportMode(_CRT_ERROR, _CRTDBG_MODE_FILE), \
   (void)_CrtSetReportFile(_CRT_ERROR, _CRTDBG_FILE_STDERR), my_abort())
#define DBUG_EXIT()                                                      \
  (_db_flush_(), (void)_CrtSetReportMode(_CRT_ERROR, _CRTDBG_MODE_FILE), \
   (void)_CrtSetReportFile(_CRT_ERROR, _CRTDBG_FILE_STDERR), _exit(2))
#endif
 
/*
  Make the program fail, without creating a core file.
  abort() will send SIGABRT which (most likely) generates core.
  Use SIGKILL instead, which cannot be caught.
  We also pause the current thread, until the signal is actually delivered.
  An alternative would be to use _exit(EXIT_FAILURE),
  but then valgrind would report lots of memory leaks.
 */
#ifdef _WIN32
#define DBUG_SUICIDE() DBUG_EXIT()
#else
[[noreturn]] extern void _db_suicide_();
extern void _db_flush_gcov_();
#define DBUG_SUICIDE() (_db_flush_(), _db_suicide_())
#endif
 
#else /* No debugger */
 
#ifdef __cplusplus
#define DBUG_TRACE \
  do {             \
  } while (false)
#endif
#define DBUG_ENTER(a1)
#define DBUG_RETURN(a1) \
  do {                  \
    return (a1);        \
  } while (0)
#define DBUG_VOID_RETURN \
  do {                   \
    return;              \
  } while (0)
#define DBUG_EXECUTE(keyword, a1) \
  do {                            \
  } while (0)
#define DBUG_EXECUTE_IF(keyword, a1) \
  do {                               \
  } while (0)
#define DBUG_EVALUATE(keyword, a1, a2) (a2)
#define DBUG_EVALUATE_IF(keyword, a1, a2) (a2)
#define DBUG_PRINT(keyword, arglist) \
  do {                               \
  } while (0)
#define DBUG_PUSH(a1) \
  do {                \
  } while (0)
#define DBUG_SET(a1) \
  do {               \
  } while (0)
#define DBUG_SET_INITIAL(a1) \
  do {                       \
  } while (0)
#define DBUG_POP() \
  do {             \
  } while (0)
#define DBUG_PROCESS(a1) \
  do {                   \
  } while (0)
#define DBUG_DUMP(keyword, a1, a2) \
  do {                             \
  } while (0)
#define DBUG_END() \
  do {             \
  } while (0)
#define DBUG_LOCK_FILE \
  do {                 \
  } while (0)
#define DBUG_FILE (stderr)
#define DBUG_UNLOCK_FILE \
  do {                   \
  } while (0)
#define DBUG_EXPLAIN(buf, len)
#define DBUG_EXPLAIN_INITIAL(buf, len)
#define DBUG_ABORT() \
  do {               \
  } while (0)
#define DBUG_SUICIDE() \
  do {                 \
  } while (0)
 
#endif
 
#ifdef __cplusplus
#if !defined(NDEBUG)
#include <sstream>
#include <string>
 
/*
  A C++ interface to the DBUG_PRINT macro.  The DBUG_LOG macro takes two
  arguments.  The first argument is the keyword, as that of the
  DBUG_PRINT.  The 2nd argument 'v' will be passed to a C++ output stream.
  This enables the use of C++ style output stream operator.  In the code, it
  will be used as follows:
 
  DBUG_LOG("blob", "space: " << space_id);
 
  Note: DBUG_PRINT() has a limitation of 1024 bytes for a single
  print out.  So, this limitation is there for DBUG_LOG macro also.
*/
 
#define DBUG_LOG(keyword, v)                           \
  do {                                                 \
    _db_pargs_(__LINE__, keyword);                     \
    if (_db_enabled_()) {                              \
      std::ostringstream sout;                         \
      sout << v;                                       \
      DBUG_PRINT(keyword, ("%s", sout.str().c_str())); \
    }                                                  \
  } while (0)
 
/**
  Shortcut for printing a variable name and its value in DBUG_LOG output.
 
  Use like:
 
  DBUG_LOG("info", DBUG_VAR(i) << " " << DBUG_VAR(thd->query));
 
  Example output for the above might be:
 
  i=[4711] thd->query=[INSERT INTO t VALUES (1)]
*/
#define DBUG_VAR(v) #v << "=[" << (v) << "]"
 
#else /* NDEBUG */
#define DBUG_LOG(keyword, v) \
  do {                       \
  } while (0)
#define DBUG_VAR(v) ""
#endif /* NDEBUG */
 
/**
   A type-safe interface to DBUG_EXECUTE_IF, where the debug action to
   activate when the keyword is provided is given as a callable object
   (typically a lambda).
 
   @note The body of the callable will be checked by the compiler even
         in optimized mode.
 
   @param keyword String literal which will enable this debug action.
   @param clos    Callable object taking no arguments which will be
                  called in debug mode if the keyword is enabled.
 */
template <class DBGCLOS>
inline void dbug(const char *keyword [[maybe_unused]],
                 DBGCLOS &&clos [[maybe_unused]]) {
  DBUG_EXECUTE_IF(keyword, clos(););
}
 
#endif /* __cplusplus */
#endif /* MY_DBUG_INCLUDED */