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