1/* ******************************************************************
2 * debug
3 * Part of FSE library
4 * Copyright (c) Yann Collet, Facebook, Inc.
5 *
6 * You can contact the author at :
7 * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy
8 *
9 * This source code is licensed under both the BSD-style license (found in the
10 * LICENSE file in the root directory of this source tree) and the GPLv2 (found
11 * in the COPYING file in the root directory of this source tree).
12 * You may select, at your option, one of the above-listed licenses.
13****************************************************************** */
14
15
16/*
17 * The purpose of this header is to enable debug functions.
18 * They regroup assert(), DEBUGLOG() and RAWLOG() for run-time,
19 * and DEBUG_STATIC_ASSERT() for compile-time.
20 *
21 * By default, DEBUGLEVEL==0, which means run-time debug is disabled.
22 *
23 * Level 1 enables assert() only.
24 * Starting level 2, traces can be generated and pushed to stderr.
25 * The higher the level, the more verbose the traces.
26 *
27 * It's possible to dynamically adjust level using variable g_debug_level,
28 * which is only declared if DEBUGLEVEL>=2,
29 * and is a global variable, not multi-thread protected (use with care)
30 */
31
32#ifndef DEBUG_H_12987983217
33#define DEBUG_H_12987983217
34
35
36
37/* static assert is triggered at compile time, leaving no runtime artefact.
38 * static assert only works with compile-time constants.
39 * Also, this variant can only be used inside a function. */
40#define DEBUG_STATIC_ASSERT(c) (void)sizeof(char[(c) ? 1 : -1])
41
42
43/* DEBUGLEVEL is expected to be defined externally,
44 * typically through compiler command line.
45 * Value must be a number. */
46#ifndef DEBUGLEVEL
47#  define DEBUGLEVEL 0
48#endif
49
50
51/* recommended values for DEBUGLEVEL :
52 * 0 : release mode, no debug, all run-time checks disabled
53 * 1 : enables assert() only, no display
54 * 2 : reserved, for currently active debug path
55 * 3 : events once per object lifetime (CCtx, CDict, etc.)
56 * 4 : events once per frame
57 * 5 : events once per block
58 * 6 : events once per sequence (verbose)
59 * 7+: events at every position (*very* verbose)
60 *
61 * It's generally inconvenient to output traces > 5.
62 * In which case, it's possible to selectively trigger high verbosity levels
63 * by modifying g_debug_level.
64 */
65
66#if (DEBUGLEVEL>=1)
67#  define ZSTD_DEPS_NEED_ASSERT
68#  include "zstd_deps.h"
69#else
70#  ifndef assert   /* assert may be already defined, due to prior #include <assert.h> */
71#    define assert(condition) ((void)0)   /* disable assert (default) */
72#  endif
73#endif
74
75#if (DEBUGLEVEL>=2)
76#  define ZSTD_DEPS_NEED_IO
77#  include "zstd_deps.h"
78extern int g_debuglevel; /* the variable is only declared,
79                            it actually lives in debug.c,
80                            and is shared by the whole process.
81                            It's not thread-safe.
82                            It's useful when enabling very verbose levels
83                            on selective conditions (such as position in src) */
84
85#  define RAWLOG(l, ...) {                                       \
86                if (l<=g_debuglevel) {                           \
87                    ZSTD_DEBUG_PRINT(__VA_ARGS__);               \
88            }   }
89#  define DEBUGLOG(l, ...) {                                     \
90                if (l<=g_debuglevel) {                           \
91                    ZSTD_DEBUG_PRINT(__FILE__ ": " __VA_ARGS__); \
92                    ZSTD_DEBUG_PRINT(" \n");                     \
93            }   }
94#else
95#  define RAWLOG(l, ...)      {}    /* disabled */
96#  define DEBUGLOG(l, ...)    {}    /* disabled */
97#endif
98
99
100
101#endif /* DEBUG_H_12987983217 */
102