Implement IO port API

Related issue: #964

Implemented the IO API of Jerry ports. Removed log file from API level.
The port implementation should define the destination of log messages.

JerryScript-DCO-1.0-Signed-off-by: László Langó llango.u-szeged@partner.samsung.com

jerry-core/jerry-api.h

@@ -162,7 +162,6 @@ typedef bool (*jerry_object_property_foreach_t) (const jerry_value_t property_na
  */
 #ifdef JERRY_ENABLE_LOG
 extern int jerry_debug_level;
-extern FILE *jerry_log_file;
 #endif /* JERRY_ENABLE_LOG */
 
 /**

jerry-core/jerry-port.h

@@ -29,12 +29,6 @@ extern "C"
  * @{
  */
 
-/**
- * Target port functions for console output
- */
-int jerry_port_logmsg (FILE *stream, const char *format, ...);
-int jerry_port_errormsg (const char *format, ...);
-
 /*
  * Termination Port API
  *
@@ -71,6 +65,54 @@ typedef enum
  */
 void jerry_port_fatal (jerry_fatal_code_t code);
 
+/*
+ *  I/O Port API
+ */
+
+/**
+ * Print a string to the console. The function should implement a printf-like
+ * interface, where the first argument specifies a format string on how to
+ * stringify the rest of the parameter list.
+ *
+ * This function is only called with strings coming from the executed ECMAScript
+ * wanting to print something as the result of its normal operation.
+ *
+ * It should be the port that decides what a "console" is.
+ *
+ * Example: a libc-based port may implement this with vprintf().
+ */
+void jerry_port_console (const char *format, ...);
+
+/**
+ * Jerry log levels. The levels are in severity order
+ * where the most serious levels come first.
+ */
+typedef enum
+{
+  JERRY_LOG_LEVEL_ERROR,    /**< the engine will terminate after the message is printed */
+  JERRY_LOG_LEVEL_WARNING,  /**< a request is aborted, but the engine continues its operation */
+  JERRY_LOG_LEVEL_DEBUG,    /**< debug messages from the engine, low volume */
+  JERRY_LOG_LEVEL_TRACE     /**< detailed info about engine internals, potentially high volume */
+} jerry_log_level_t;
+
+/**
+ * Display or log a debug/error message. The function should implement a printf-like
+ * interface, where the first argument specifies the log level
+ * and the second argument specifies a format string on how to stringify the rest
+ * of the parameter list.
+ *
+ * This function is only called with messages coming from the jerry engine as
+ * the result of some abnormal operation or describing its internal operations
+ * (e.g., data structure dumps or tracing info).
+ *
+ * It should be the port that decides whether error and debug messages are logged to
+ * the console, or saved to a database or to a file.
+ *
+ * Example: a libc-based port may implement this with vfprintf(stderr) or
+ * vfprintf(logfile), or both, depending on log level.
+ */
+void jerry_port_log (jerry_log_level_t level, const char *format, ...);
+
 /*
  * Date Port API
  */

jerry-core/jerry.c

@@ -86,11 +86,6 @@ static const char *wrong_args_msg_p = "wrong type of argument";
  */
 int jerry_debug_level = 0;
 
-/**
- * File, used for logging
- */
-FILE *jerry_log_file = NULL;
-
 #endif /* JERRY_ENABLE_LOG */
 
 /**

jerry-core/jrt/jrt.h

@@ -86,9 +86,9 @@ extern void __noreturn jerry_unimplemented (const char *, const char *, const ch
 #define JERRY_LOG(lvl, ...) \
   do \
   { \
-    if (lvl <= jerry_debug_level && jerry_log_file) \
+    if (lvl <= jerry_debug_level) \
     { \
-      jerry_port_logmsg (jerry_log_file, __VA_ARGS__); \
+      jerry_port_log (JERRY_LOG_LEVEL_DEBUG, __VA_ARGS__); \
     } \
   } \
   while (0)
@@ -109,8 +109,8 @@ extern void __noreturn jerry_unimplemented (const char *, const char *, const ch
 #define JERRY_DDDLOG(...) JERRY_DLOG (__VA_ARGS__)
 #endif /* JERRY_ENABLE_LOG */
 
-#define JERRY_ERROR_MSG(...) jerry_port_errormsg (__VA_ARGS__)
-#define JERRY_WARNING_MSG(...) JERRY_ERROR_MSG (__VA_ARGS__)
+#define JERRY_ERROR_MSG(...) jerry_port_log (JERRY_LOG_LEVEL_ERROR, __VA_ARGS__)
+#define JERRY_WARNING_MSG(...) jerry_port_log (JERRY_LOG_LEVEL_WARNING, __VA_ARGS__)
 
 /**
  * Mark for unreachable points and unimplemented cases