#include <v8.h>
#include <v8-debug.h>
#include <fcntl.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>

Include dependency graph for lineprocessor.cc:

Macros
#define	SUPPORT_DEBUGGING

Enumerations
enum	MainCycleType { CycleInCpp, CycleInJs }

Functions
const char *	ToCString (const v8::String::Utf8Value &value)

void	ReportException (v8::TryCatch *handler)

v8::Handle< v8::String >	ReadFile (const char *name)

v8::Handle< v8::String >	ReadLine ()

v8::Handle< v8::Value >	Print (const v8::Arguments &args)

v8::Handle< v8::Value >	ReadLine (const v8::Arguments &args)

bool	RunCppCycle (v8::Handle< v8::Script > script, v8::Local< v8::Context > context, bool report_exceptions)

void	DispatchDebugMessages ()

int	RunMain (int argc, char *argv[])

int	main (int argc, char *argv[])

Variables
v8::Persistent< v8::Context >	debug_message_context

Macro Definition Documentation

#define SUPPORT_DEBUGGING

Definition at line 34 of file lineprocessor.cc.

Enumeration Type Documentation

enum MainCycleType

This sample program should demonstrate certain aspects of debugging standalone V8-based application.

The program reads input stream, processes it line by line and print the result to output. The actual processing is done by custom JavaScript script. The script is specified with command line parameters.

The main cycle of the program will sequentially read lines from standard input, process them and print to standard output until input closes. There are 2 possible configuration in regard to main cycle.

The main cycle is on C++ side. Program should be run with –main-cycle-in-cpp option. Script must declare a function named "ProcessLine". The main cycle in C++ reads lines and calls this function for processing every time. This is a sample script:

function ProcessLine(input_line) { return ">>>" + input_line + "<<<"; }

The main cycle is in JavaScript. Program should be run with –main-cycle-in-js option. Script gets run one time at all and gets API of 2 global functions: "read_line" and "print". It should read input and print converted lines to output itself. This a sample script:

while (true) { var line = read_line(); if (!line) { break; } var res = line + " | " + line; print(res); }

When run with "-p" argument, the program starts V8 Debugger Agent and allows remote debugger to attach and debug JavaScript code.

Interesting aspects:

Wait for remote debugger to attach Normally the program compiles custom script and immediately runs it. If programmer needs to debug script from the very beginning, he should run this sample program with "--wait-for-connection" command line parameter. This way V8 will suspend on the first statement and wait for debugger to attach.
Unresponsive V8 V8 Debugger Agent holds a connection with remote debugger, but it does respond only when V8 is running some script. In particular, when this program is waiting for input, all requests from debugger get deferred until V8 is called again. See how "--callback" command-line parameter in this sample fixes this issue.