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