CC Stacktrace

local args = {...}
local switches = {}
local _fsopen = fs.open

local UNIQUECHUNKNAME = "trace/root"

local function printHelp()
    local pname = shell.getRunningProgram()
    print("Usage: " .. (pname:match("/(.-)$") or pname) .. " [switches...] <program> [args...]")
    print("Switches:")
    print("  -h         show this message")
    print("  -l<FILE>   log trace to <FILE> (append mode)")
    print("  -f         show full trace (including bios.lua)")
    print("  -m<MAX>    set max trace depth to <MAX>")
    print("                (there's no maximum by default)")
    print("  -b         break trace into separate lines")
end

local logfile
function switches.l(rest)
    logfile = rest
end

function switches.h()
    printHelp()
    return true -- exit
end

local maxdepth
function switches.m(rest)
    maxdepth = tonumber(rest)
    if not maxdepth or maxdepth < 1 then
        print("Invalid max depth: " .. rest)
    end
end

local breakintolines
function switches.b()
    breakintolines = true
end

local fulltrace
function switches.f()
    fulltrace = true
end

while args[1] do
    if not args[1]:match("^%-") then break end
    local switchf = args[1]:sub(2, 2)
    if switches[switchf] then
        if switches[switchf](args[1]:sub(3)) then return end
    else
        print("Unknown switch: " .. switchf)
    end
    table.remove(args, 1)
end

if not args[1] then
    printHelp()
    return
end

local ffunc = loadfile(args[1], setmetatable({shell = shell}, {__index = _G}))
if not ffunc then
    print("Failed to load program")
    return
end

load([[xpcall(func, handler)]], UNIQUECHUNKNAME, "t", {
    xpcall = xpcall,
    func = function()
        ffunc(table.unpack(args, 2))
    end,
    handler = function(xpcallerr)
        local loghandle
        if logfile then
            loghandle = _fsopen(logfile, "a")
        end

        local tracerestbl = {xpcallerr .. "\n  stack trace:"}
        local level = 1
        while true do
            local nope, errstr = pcall(error, "@", level + 2)
            if errstr == "@" then break end
            if not fulltrace and errstr:match("^(.-):") == UNIQUECHUNKNAME then
                tracerestbl[#tracerestbl] = nil
                tracerestbl[#tracerestbl] = nil -- yup, twice
                break
            end
            tracerestbl[#tracerestbl + 1] = errstr:match("^(.+): @$")
            if level == maxdepth then break end
            level = level + 1
        end

        local traceres = table.concat(tracerestbl, breakintolines and "\n    " or " ")

        printError(traceres)
        if loghandle then
            loghandle.writeLine(traceres)
            loghandle.close()
        end
    end
})()