1 files changed, 57 insertions, 0 deletions
diff --git a/kernel_call/log.h b/kernel_call/log.h
new file mode 100755
index 0000000..af1920f
--- /dev/null
+++ b/kernel_call/log.h
@@ -0,0 +1,57 @@
+/*
+ * log.h
+ * Brandon Azad
+ */
+#ifndef VOUCHER_SWAP__LOG_H_
+#define VOUCHER_SWAP__LOG_H_
+
+#include <stdarg.h>
+#include <stdio.h>
+
+/*
+ * log_implementation
+ *
+ * Description:
+ * 	This is the log handler that will be executed when code wants to log a message. The default
+ * 	implementation logs the message to stderr. Setting this value to NULL will disable all
+ * 	logging. Specify a custom log handler to process log messages in another way.
+ *
+ * Parameters:
+ * 	type				A character representing the type of message that is being
+ * 					logged.
+ * 	format				A printf-style format string describing the error message.
+ * 	ap				The variadic argument list for the format string.
+ *
+ * Log Type:
+ * 	The type parameter is one of:
+ * 	- D: Debug:     Used for debugging messages. Set the DEBUG build variable to control debug
+ * 	                verbosity.
+ * 	- I: Info:      Used to convey general information about the exploit or its progress.
+ * 	- W: Warning:   Used to indicate that an unusual but possibly recoverable condition was
+ * 	                encountered.
+ * 	- E: Error:     Used to indicate that an unrecoverable error was encountered. The code
+ * 	                might continue running after an error was encountered, but it probably will
+ * 	                not succeed.
+ */
+extern void (*log_implementation)(char type, const char *format, va_list ap);
+
+#define DEBUG_LEVEL(level)	(DEBUG && level <= DEBUG)
+
+#if DEBUG
+#define DEBUG_TRACE(level, fmt, ...)						\
+	do {									\
+		if (DEBUG_LEVEL(level)) {					\
+			log_internal('D', fmt, ##__VA_ARGS__);			\
+		}								\
+	} while (0)
+#else
+#define DEBUG_TRACE(level, fmt, ...)	do {} while (0)
+#endif
+#define INFO(fmt, ...)		log_internal('I', fmt, ##__VA_ARGS__)
+#define WARNING(fmt, ...)	log_internal('W', fmt, ##__VA_ARGS__)
+#define ERROR(fmt, ...)		log_internal('E', fmt, ##__VA_ARGS__)
+
+// A function to call the logging implementation.
+void log_internal(char type, const char *format, ...) __printflike(2, 3);
+
+#endif