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 void trace_repo_setup(const char *prefix);
  21 int trace_want(struct trace_key *key);
  22 void trace_disable(struct trace_key *key);
  23 uint64_t getnanotime(void);
  24 void trace_command_performance(const char **argv);
  25 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 void trace_printf(const char *format, ...);
  32
  33 __attribute__((format (printf, 2, 3)))
  34 void trace_printf_key(struct trace_key *key, const char *format, ...);
  35
  36 __attribute__((format (printf, 2, 3)))
  37 void trace_argv_printf(const char **argv, const char *format, ...);
  38
  39 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 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 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 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 void trace_argv_printf_fl(const char *file, int line, const char **argv,
 139                           const char *format, ...);
 140 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 void trace_performance_fl(const char *file, int line,
 144                           uint64_t nanos, const char *fmt, ...);
 145 __attribute__((format (printf, 4, 5)))
 146 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 */