Fourth batch for 2.20
[git] / trace.h
1 #ifndef TRACE_H
2 #define TRACE_H
3
4 #include "git-compat-util.h"
5 #include "strbuf.h"
6
7 struct trace_key {
8         const char * const key;
9         int fd;
10         unsigned int initialized : 1;
11         unsigned int  need_close : 1;
12 };
13
14 extern struct trace_key trace_default_key;
15
16 #define TRACE_KEY_INIT(name) { "GIT_TRACE_" #name, 0, 0, 0 }
17 extern struct trace_key trace_perf_key;
18 extern struct trace_key trace_setup_key;
19
20 extern void trace_repo_setup(const char *prefix);
21 extern int trace_want(struct trace_key *key);
22 extern void trace_disable(struct trace_key *key);
23 extern uint64_t getnanotime(void);
24 extern void trace_command_performance(const char **argv);
25 extern void trace_verbatim(struct trace_key *key, const void *buf, unsigned len);
26 uint64_t trace_performance_enter(void);
27
28 #ifndef HAVE_VARIADIC_MACROS
29
30 __attribute__((format (printf, 1, 2)))
31 extern void trace_printf(const char *format, ...);
32
33 __attribute__((format (printf, 2, 3)))
34 extern void trace_printf_key(struct trace_key *key, const char *format, ...);
35
36 __attribute__((format (printf, 2, 3)))
37 extern void trace_argv_printf(const char **argv, const char *format, ...);
38
39 extern void trace_strbuf(struct trace_key *key, const struct strbuf *data);
40
41 /* Prints elapsed time (in nanoseconds) if GIT_TRACE_PERFORMANCE is enabled. */
42 __attribute__((format (printf, 2, 3)))
43 extern void trace_performance(uint64_t nanos, const char *format, ...);
44
45 /* Prints elapsed time since 'start' if GIT_TRACE_PERFORMANCE is enabled. */
46 __attribute__((format (printf, 2, 3)))
47 extern void trace_performance_since(uint64_t start, const char *format, ...);
48
49 __attribute__((format (printf, 1, 2)))
50 void trace_performance_leave(const char *format, ...);
51
52 #else
53
54 /*
55  * Macros to add file:line - see above for C-style declarations of how these
56  * should be used.
57  */
58
59 /*
60  * TRACE_CONTEXT may be set to __FUNCTION__ if the compiler supports it. The
61  * default is __FILE__, as it is consistent with assert(), and static function
62  * names are not necessarily unique.
63  *
64  * __FILE__ ":" __FUNCTION__ doesn't work with GNUC, as __FILE__ is supplied
65  * by the preprocessor as a string literal, and __FUNCTION__ is filled in by
66  * the compiler as a string constant.
67  */
68 #ifndef TRACE_CONTEXT
69 # define TRACE_CONTEXT __FILE__
70 #endif
71
72 /*
73  * Note: with C99 variadic macros, __VA_ARGS__ must include the last fixed
74  * parameter ('format' in this case). Otherwise, a call without variable
75  * arguments will have a surplus ','. E.g.:
76  *
77  *  #define foo(format, ...) bar(format, __VA_ARGS__)
78  *  foo("test");
79  *
80  * will expand to
81  *
82  *  bar("test",);
83  *
84  * which is invalid (note the ',)'). With GNUC, '##__VA_ARGS__' drops the
85  * comma, but this is non-standard.
86  */
87
88 #define trace_printf_key(key, ...)                                          \
89         do {                                                                \
90                 if (trace_pass_fl(key))                                     \
91                         trace_printf_key_fl(TRACE_CONTEXT, __LINE__, key,   \
92                                             __VA_ARGS__);                   \
93         } while (0)
94
95 #define trace_printf(...) trace_printf_key(&trace_default_key, __VA_ARGS__)
96
97 #define trace_argv_printf(argv, ...)                                        \
98         do {                                                                \
99                 if (trace_pass_fl(&trace_default_key))                      \
100                         trace_argv_printf_fl(TRACE_CONTEXT, __LINE__,       \
101                                             argv, __VA_ARGS__);             \
102         } while (0)
103
104 #define trace_strbuf(key, data)                                             \
105         do {                                                                \
106                 if (trace_pass_fl(key))                                     \
107                         trace_strbuf_fl(TRACE_CONTEXT, __LINE__, key, data);\
108         } while (0)
109
110 #define trace_performance(nanos, ...)                                       \
111         do {                                                                \
112                 if (trace_pass_fl(&trace_perf_key))                         \
113                         trace_performance_fl(TRACE_CONTEXT, __LINE__, nanos,\
114                                              __VA_ARGS__);                  \
115         } while (0)
116
117 #define trace_performance_since(start, ...)                                 \
118         do {                                                                \
119                 if (trace_pass_fl(&trace_perf_key))                         \
120                         trace_performance_fl(TRACE_CONTEXT, __LINE__,       \
121                                              getnanotime() - (start),       \
122                                              __VA_ARGS__);                  \
123         } while (0)
124
125 #define trace_performance_leave(...)                                        \
126         do {                                                                \
127                 if (trace_pass_fl(&trace_perf_key))                         \
128                         trace_performance_leave_fl(TRACE_CONTEXT, __LINE__, \
129                                                    getnanotime(),           \
130                                                    __VA_ARGS__);            \
131         } while (0)
132
133 /* backend functions, use non-*fl macros instead */
134 __attribute__((format (printf, 4, 5)))
135 extern void trace_printf_key_fl(const char *file, int line, struct trace_key *key,
136                                 const char *format, ...);
137 __attribute__((format (printf, 4, 5)))
138 extern void trace_argv_printf_fl(const char *file, int line, const char **argv,
139                                  const char *format, ...);
140 extern void trace_strbuf_fl(const char *file, int line, struct trace_key *key,
141                             const struct strbuf *data);
142 __attribute__((format (printf, 4, 5)))
143 extern void trace_performance_fl(const char *file, int line,
144                                  uint64_t nanos, const char *fmt, ...);
145 __attribute__((format (printf, 4, 5)))
146 extern void trace_performance_leave_fl(const char *file, int line,
147                                        uint64_t nanos, const char *fmt, ...);
148 static inline int trace_pass_fl(struct trace_key *key)
149 {
150         return key->fd || !key->initialized;
151 }
152
153 #endif /* HAVE_VARIADIC_MACROS */
154
155 #endif /* TRACE_H */