Add new command line argument to chrome

To add a new command-line argument to Chrome, you'll need to modify the chrome executable and rebuild it. Here's a step-by-step guide:

Prerequisites:

1. You have a basic understanding of C++ and the Chrome source code.
2. You have a development environment set up with the necessary tools (e.g., git, cmake, ninja, and a C++ compiler).
3. You have a copy of the Chrome source code (you can clone it from the official repository: git clone https://chromium.googlesource.com/chromium/src.git).

Step 1: Create a new file for the command-line argument

In the chrome directory, create a new file called args.cc (or any other name that follows the Chrome naming convention). This file will contain the implementation of your new command-line argument.

Step 2: Define the command-line argument

In args.cc, add the following code to define your new command-line argument:

#include "base/command_line.h"
#include "base/strings/string_piece.h"

namespace chrome {

// Define the new command-line argument
CommandLineFlag::StringFlag* CreateMyFlag() {
  return new CommandLineFlag::StringFlag("my-flag", "My flag", "my-flag-help");
}

}  // namespace chrome

This code defines a new command-line argument called --my-flag with a short description and a help message.

Step 3: Register the command-line argument

In args.cc, add the following code to register your new command-line argument:

#include "chrome/browser/chrome_browser_main_parts.h"

namespace chrome {

// Register the new command-line argument
void RegisterMyFlag(CommandLine* command_line) {
  command_line->AppendFlag(&CreateMyFlag());
}

}  // namespace chrome

This code registers the --my-flag argument with the CommandLine object.

Step 4: Update the chrome executable

In the chrome directory, run the following command to update the chrome executable:

ninja -C out/Default chrome

This will rebuild the chrome executable with the new command-line argument.

Step 5: Test the new command-line argument

Run the updated chrome executable with the new command-line argument:

./chrome --my-flag="my-value"

You should see the help message for the --my-flag argument:

chrome --my-flag="my-value"
chrome: unrecognized option '--my-flag'
chrome: Try 'chrome --help' for more information.
chrome: My flag: my-flag-help

Congratulations! You have successfully added a new command-line argument to Chrome.

Note: This is a simplified example, and you may need to modify the code to fit your specific use case. Additionally, you'll need to ensure that your new command-line argument is properly handled by the Chrome codebase.