ut0dbg.h

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/** @file include/ut0dbg.h
 Debug utilities for Innobase
 
 Created 1/30/1994 Heikki Tuuri
 **********************************************************************/
 
#ifndef ut0dbg_h
#define ut0dbg_h
 
#include "my_compiler.h"
#include "my_dbug.h"
/* Do not include univ.i because univ.i includes this. */
 
#include <cstdint>
#include <cstdio>
#include <functional>
#include <sstream>
 
/** Set a callback function to be called before exiting.
@param[in]      callback        user callback function */
void ut_set_assert_callback(std::function<void()> &callback);
 
/** Terminates execution of the current process. */
[[noreturn]] void ut_fatal_error();
 
/** Report a failed assertion.
@param[in] expr The failed assertion
@param[in] file Source file containing the assertion
@param[in] line Line number of the assertion */
[[noreturn]] void ut_dbg_assertion_failed(const char *expr, const char *file,
                                          uint64_t line);
 
template <typename L, typename R>
[[noreturn]] void inline ut_dbg_comparison_failed(
    const char *lhs_expr, const L &lhs_value, const char *op,
    const char *rhs_expr, const R &rhs_value, const char *file, uint64_t line) {
  std::ostringstream text;
  text << lhs_expr << " == " << lhs_value << ' ' << op << ' ' << rhs_value
       << " == " << rhs_expr;
  ut_dbg_assertion_failed(text.str().c_str(), file, line);
}
 
/** Assert that LHS OP RHS, where OP is an operator.
Abort execution otherwise.
Technical remarks: The LHS and RHS are evaluated exactly once (no short
circuiting, even if OP is && or ||). Each value is stored in a local variable,
so it's fine for LHS or RHS to return a temporary.
In case of assertion failure references to const values of LHS and RHS will be
passed to std::ostringstream::operator<<, so it must be implemented for them. */
#define ut_a_op(LHS, OP, RHS)                                                  \
  do {                                                                         \
    const auto lhs{LHS};                                                       \
    const auto rhs{RHS};                                                       \
    if (unlikely(!(lhs OP rhs))) {                                             \
      ut_dbg_comparison_failed(#LHS, lhs, #OP, #RHS, rhs, __FILE__, __LINE__); \
    }                                                                          \
  } while (0)
 
/** Assert that LHS < RHS. Abort execution otherwise. */
#define ut_a_lt(LHS, RHS) ut_a_op(LHS, <, RHS)
/** Assert that LHS <= RHS. Abort execution otherwise. */
#define ut_a_le(LHS, RHS) ut_a_op(LHS, <=, RHS)
/** Assert that LHS == RHS. Abort execution otherwise. */
#define ut_a_eq(LHS, RHS) ut_a_op(LHS, ==, RHS)
/** Assert that LHS != RHS. Abort execution otherwise. */
#define ut_a_ne(LHS, RHS) ut_a_op(LHS, !=, RHS)
 
/** Abort execution if EXPR does not evaluate to nonzero.
@param EXPR assertion expression that should hold */
#define ut_a(EXPR)                                        \
  do {                                                    \
    if (unlikely(false == (bool)(EXPR))) {                \
      ut_dbg_assertion_failed(#EXPR, __FILE__, __LINE__); \
    }                                                     \
  } while (0)
 
/** Abort execution. */
#define ut_error ut_dbg_assertion_failed(nullptr, __FILE__, __LINE__)
 
#ifdef UNIV_DEBUG
/** Debug assertion. Does nothing unless UNIV_DEBUG is defined. */
#define ut_ad(EXPR) ut_a(EXPR)
/** Debug statement. Does nothing unless UNIV_DEBUG is defined. */
#define ut_d(EXPR) EXPR
/** Opposite of ut_d().  Does nothing if UNIV_DEBUG is defined. */
#define ut_o(EXPR)
/** Debug-only assertion that LHS < RHS. */
#define ut_ad_lt(LHS, RHS) ut_a_lt(LHS, RHS)
/** Debug-only assertion that LHS <= RHS. */
#define ut_ad_le(LHS, RHS) ut_a_le(LHS, RHS)
/** Debug-only assertion that LHS == RHS. */
#define ut_ad_eq(LHS, RHS) ut_a_eq(LHS, RHS)
/** Assert that LHS != RHS. Abort execution otherwise. */
#define ut_ad_ne(LHS, RHS) ut_a_op(LHS, !=, RHS)
#else
/** Debug assertion. Does nothing unless UNIV_DEBUG is defined. */
#define ut_ad(EXPR)
/** Debug statement. Does nothing unless UNIV_DEBUG is defined. */
#define ut_d(EXPR)
/** Opposite of ut_d().  Does nothing if UNIV_DEBUG is defined. */
#define ut_o(EXPR) EXPR
/** Debug-only assertion that LHS < RHS. */
#define ut_ad_lt(LHS, RHS)
/** Debug-only assertion that LHS <= RHS. */
#define ut_ad_le(LHS, RHS)
/** Debug-only assertion that LHS == RHS. */
#define ut_ad_eq(LHS, RHS)
/** Assert that LHS != RHS. */
#define ut_ad_ne(LHS, RHS)
#endif
 
/** Debug crash point */
 
#ifdef UNIV_DEBUG
inline void DBUG_INJECT_CRASH(const char *prefix, unsigned count) {
  char buf[64];
  snprintf(buf, sizeof buf, "%s_%u", prefix, count);
  DBUG_EXECUTE_IF(buf, DBUG_SUICIDE(););
}
#else
#define DBUG_INJECT_CRASH(prefix, count)
#endif
 
/** Silence warnings about an unused variable by doing a null assignment.
@param A the unused variable */
#define UT_NOT_USED(A) std::ignore = A
 
#if defined(HAVE_SYS_TIME_H) && defined(HAVE_SYS_RESOURCE_H)
 
#define HAVE_UT_CHRONO_T
 
#include <sys/resource.h>
#include <sys/time.h>
#include <sys/types.h>
 
/** A "chronometer" used to clock snippets of code.
Example usage:
        ut_chrono_t     ch("this loop");
        for (;;) { ... }
        ch.show();
would print the timings of the for() loop, prefixed with "this loop:" */
class ut_chrono_t {
 public:
  /** Constructor.
  @param[in]    name    chrono's name, used when showing the values */
  ut_chrono_t(const char *name) : m_name(name), m_show_from_destructor(true) {
    reset();
  }
 
  /** Resets the chrono (records the current time in it). */
  void reset() {
    gettimeofday(&m_tv, nullptr);
 
    getrusage(RUSAGE_SELF, &m_ru);
  }
 
  /** Shows the time elapsed and usage statistics since the last reset. */
  void show() {
    struct rusage ru_now;
    struct timeval tv_now;
    struct timeval tv_diff;
 
    getrusage(RUSAGE_SELF, &ru_now);
 
    gettimeofday(&tv_now, nullptr);
 
#ifndef timersub
#define timersub(a, b, r)                       \
  do {                                          \
    (r)->tv_sec = (a)->tv_sec - (b)->tv_sec;    \
    (r)->tv_usec = (a)->tv_usec - (b)->tv_usec; \
    if ((r)->tv_usec < 0) {                     \
      (r)->tv_sec--;                            \
      (r)->tv_usec += 1000000;                  \
    }                                           \
  } while (0)
#endif /* timersub */
 
#define CHRONO_PRINT(type, tvp)                            \
  fprintf(stderr, "%s: %s% 5ld.%06ld sec\n", m_name, type, \
          static_cast<long>((tvp)->tv_sec), static_cast<long>((tvp)->tv_usec))
 
    timersub(&tv_now, &m_tv, &tv_diff);
    CHRONO_PRINT("real", &tv_diff);
 
    timersub(&ru_now.ru_utime, &m_ru.ru_utime, &tv_diff);
    CHRONO_PRINT("user", &tv_diff);
 
    timersub(&ru_now.ru_stime, &m_ru.ru_stime, &tv_diff);
    CHRONO_PRINT("sys ", &tv_diff);
  }
 
  /** Cause the timings not to be printed from the destructor. */
  void end() { m_show_from_destructor = false; }
 
  /** Destructor. */
  ~ut_chrono_t() {
    if (m_show_from_destructor) {
      show();
    }
  }
 
 private:
  /** Name of this chronometer. */
  const char *m_name;
 
  /** True if the current timings should be printed by the destructor. */
  bool m_show_from_destructor;
 
  /** getrusage() result as of the last reset(). */
  struct rusage m_ru;
 
  /** gettimeofday() result as of the last reset(). */
  struct timeval m_tv;
};
 
#endif /* HAVE_SYS_TIME_H && HAVE_SYS_RESOURCE_H */
 
#endif