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$function

Version information

Introduced in version v0.1

This macro is considered stable

About

The $function macro allows v5dbg to generate a backtrace to determine the current point of execution. When placed at the top of a function it adds debug information to the current backtrace, when the function exits its then removed.

Why do I need to use this macro?

Unlike traditional debuggers which can ask the operating system for a backtrace and can then convert the returned addresses into symbol names, v5dbg runs on an environment where this is not possible (yet).

As a workaround $function traces where it was called from to determine the proper line of execution.

Notes

Required environment

  • This macro requires the debug server to have been initialized before being called.
  • This macro requires the current thread to be supervised with $ntask or V5Dbg_Init

Examples

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#include "v5dbg/debug.h"

void
opcontrol()
{
    $ntask // (1)
    $function // (2)

    while (true)
    {
        // Print "Hello World" to the screen via pros::lcd
        pros::lcd::print(1, "Hello World");

        pros::delay(300);
    }
}
  1. For more information on $ntask look here
  2. Now opcontrol will be the first item in the callstack since it's the first time $function was called on this thread/task.
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#include "v5dbg/debug.h"

void
printAndSleep(const std::string &p)
{
    $function // (2)
    pros::lcd::print(1, "%s", p.c_str()); // Print our data to the screen

    pros::delay(300); // Wait 300ms
}

void
opcontrol()
{
    $ntask // (1)
    $function

    while (true)
    {
        printAndSleep("Hello World");
    }
}
  1. For more information on $ntask look here
  2. Now our printAndSleep function will be the second item in the callstack, it should now look like this:
    • void printAndSleep(const std::string &p)
    • void opcontrol()