Squashed 'third_party/git/' content from commit cb71568594

git-subtree-dir: third_party/git
git-subtree-split: cb715685942260375e1eb8153b0768a376e4ece7

trace.h

@@ -0,0 +1,155 @@
+#ifndef TRACE_H
+#define TRACE_H
+
+#include "git-compat-util.h"
+#include "strbuf.h"
+
+struct trace_key {
+	const char * const key;
+	int fd;
+	unsigned int initialized : 1;
+	unsigned int  need_close : 1;
+};
+
+extern struct trace_key trace_default_key;
+
+#define TRACE_KEY_INIT(name) { "GIT_TRACE_" #name, 0, 0, 0 }
+extern struct trace_key trace_perf_key;
+extern struct trace_key trace_setup_key;
+
+void trace_repo_setup(const char *prefix);
+int trace_want(struct trace_key *key);
+void trace_disable(struct trace_key *key);
+uint64_t getnanotime(void);
+void trace_command_performance(const char **argv);
+void trace_verbatim(struct trace_key *key, const void *buf, unsigned len);
+uint64_t trace_performance_enter(void);
+
+#ifndef HAVE_VARIADIC_MACROS
+
+__attribute__((format (printf, 1, 2)))
+void trace_printf(const char *format, ...);
+
+__attribute__((format (printf, 2, 3)))
+void trace_printf_key(struct trace_key *key, const char *format, ...);
+
+__attribute__((format (printf, 2, 3)))
+void trace_argv_printf(const char **argv, const char *format, ...);
+
+void trace_strbuf(struct trace_key *key, const struct strbuf *data);
+
+/* Prints elapsed time (in nanoseconds) if GIT_TRACE_PERFORMANCE is enabled. */
+__attribute__((format (printf, 2, 3)))
+void trace_performance(uint64_t nanos, const char *format, ...);
+
+/* Prints elapsed time since 'start' if GIT_TRACE_PERFORMANCE is enabled. */
+__attribute__((format (printf, 2, 3)))
+void trace_performance_since(uint64_t start, const char *format, ...);
+
+__attribute__((format (printf, 1, 2)))
+void trace_performance_leave(const char *format, ...);
+
+#else
+
+/*
+ * Macros to add file:line - see above for C-style declarations of how these
+ * should be used.
+ */
+
+/*
+ * TRACE_CONTEXT may be set to __FUNCTION__ if the compiler supports it. The
+ * default is __FILE__, as it is consistent with assert(), and static function
+ * names are not necessarily unique.
+ *
+ * __FILE__ ":" __FUNCTION__ doesn't work with GNUC, as __FILE__ is supplied
+ * by the preprocessor as a string literal, and __FUNCTION__ is filled in by
+ * the compiler as a string constant.
+ */
+#ifndef TRACE_CONTEXT
+# define TRACE_CONTEXT __FILE__
+#endif
+
+/*
+ * Note: with C99 variadic macros, __VA_ARGS__ must include the last fixed
+ * parameter ('format' in this case). Otherwise, a call without variable
+ * arguments will have a surplus ','. E.g.:
+ *
+ *  #define foo(format, ...) bar(format, __VA_ARGS__)
+ *  foo("test");
+ *
+ * will expand to
+ *
+ *  bar("test",);
+ *
+ * which is invalid (note the ',)'). With GNUC, '##__VA_ARGS__' drops the
+ * comma, but this is non-standard.
+ */
+
+#define trace_printf_key(key, ...)					    \
+	do {								    \
+		if (trace_pass_fl(key))					    \
+			trace_printf_key_fl(TRACE_CONTEXT, __LINE__, key,   \
+					    __VA_ARGS__);		    \
+	} while (0)
+
+#define trace_printf(...) trace_printf_key(&trace_default_key, __VA_ARGS__)
+
+#define trace_argv_printf(argv, ...)					    \
+	do {								    \
+		if (trace_pass_fl(&trace_default_key))			    \
+			trace_argv_printf_fl(TRACE_CONTEXT, __LINE__,	    \
+					    argv, __VA_ARGS__);		    \
+	} while (0)
+
+#define trace_strbuf(key, data)						    \
+	do {								    \
+		if (trace_pass_fl(key))					    \
+			trace_strbuf_fl(TRACE_CONTEXT, __LINE__, key, data);\
+	} while (0)
+
+#define trace_performance(nanos, ...)					    \
+	do {								    \
+		if (trace_pass_fl(&trace_perf_key))			    \
+			trace_performance_fl(TRACE_CONTEXT, __LINE__, nanos,\
+					     __VA_ARGS__);		    \
+	} while (0)
+
+#define trace_performance_since(start, ...)				    \
+	do {								    \
+		if (trace_pass_fl(&trace_perf_key))			    \
+			trace_performance_fl(TRACE_CONTEXT, __LINE__,       \
+					     getnanotime() - (start),	    \
+					     __VA_ARGS__);		    \
+	} while (0)
+
+#define trace_performance_leave(...)					    \
+	do {								    \
+		if (trace_pass_fl(&trace_perf_key))			    \
+			trace_performance_leave_fl(TRACE_CONTEXT, __LINE__, \
+						   getnanotime(),	    \
+						   __VA_ARGS__);	    \
+	} while (0)
+
+/* backend functions, use non-*fl macros instead */
+__attribute__((format (printf, 4, 5)))
+void trace_printf_key_fl(const char *file, int line, struct trace_key *key,
+			 const char *format, ...);
+__attribute__((format (printf, 4, 5)))
+void trace_argv_printf_fl(const char *file, int line, const char **argv,
+			  const char *format, ...);
+void trace_strbuf_fl(const char *file, int line, struct trace_key *key,
+		     const struct strbuf *data);
+__attribute__((format (printf, 4, 5)))
+void trace_performance_fl(const char *file, int line,
+			  uint64_t nanos, const char *fmt, ...);
+__attribute__((format (printf, 4, 5)))
+void trace_performance_leave_fl(const char *file, int line,
+				uint64_t nanos, const char *fmt, ...);
+static inline int trace_pass_fl(struct trace_key *key)
+{
+	return key->fd || !key->initialized;
+}
+
+#endif /* HAVE_VARIADIC_MACROS */
+
+#endif /* TRACE_H */