Algorithm Debugger: gcc and gdb

Ensure code is compiled with -g or -ggdb flag so that debugging information is produced that gdb can use

Useful Commands

r: Run the program
b {function_name | line_number}: Puts breakpoint at beginning of function or at a line number
info args: Prints function argument values of the current frame
info locals: Prints local variable values of the current frame
p *{array}@{n}: Prints n values of the array (ideally n is the array length)
ptype {struct}: Prints details about type (useful for printing fields in a struct)
n: Step into the next line of the current function, doesn’t step into functions
s: Step into the next line of the program: Should probably avoid and use breakpoints for important functions instead
frame: Prints the current stack frame + the line of code run (maybe useful for code line highlighting?)
where: Prints information about all stack frames

How to compile user C code? Using an external system like piston or judge0? Or subprocess (sounds kinda doomed for security)
How to run gdb through node? help i’m absolutely clueless (I can only think of using a subprocess)
Would the user keep connection with gdb the entire time (this doesn’t seem feasible for performance + creating a timeline the user has control over doesn’t seem so easy but i could be very wrong), or is the operation performed in one big swoop?
What would the backend return? Perhaps a series of instructions that are given to svg.js? (eg. create circle in svg.js with property address=0x000555…)
How does the user input an operation? (If there is no main function, is there another way besides the drawing tool?)
People’s assignment code (especially COMP2521) may have data too large to visualize (eg. 500000 size array), how do we make sure this won’t break our website.