pinnacle/pinnacle_api_lua/init.lua

-- require("luarocks.loader") TODO:

local socket = require("posix.sys.socket")
local msgpack = require("msgpack")

local SOCKET_PATH = "/tmp/pinnacle_socket"

---@type integer
local socket_fd = assert(socket.socket(socket.AF_UNIX, socket.SOCK_STREAM, 0), "Failed to create socket")
print("created socket at fd " .. socket_fd)

assert(0 == socket.connect(socket_fd, {
    family = socket.AF_UNIX,
    path = SOCKET_PATH,
}), "Failed to connect to Pinnacle socket")

function SendMsg(data)
    local encoded = msgpack.encode(data)
    assert(encoded)
    local len = encoded:len()
    socket.send(socket_fd, string.pack("=I4", len))
    socket.send(socket_fd, encoded)
end

---@type fun()[]
CallbackTable = {}

local CONFIG_PATH = os.getenv("PINNACLE_CONFIG")
dofile(CONFIG_PATH)

---Read the specified number of bytes.
---@param socket_fd integer The socket file descriptor
---@param count integer The amount of bytes to read
---@return string|nil data
---@return string|nil err_msg
---@return integer|nil err_num
local function read_exact(socket_fd, count)
    local len_to_read = count
    local data = ""
    while len_to_read > 0 do
        local bytes, err_msg, errnum = socket.recv(socket_fd, len_to_read)

        if bytes == nil then
            -- TODO: handle errors
            print("bytes was nil")
            return bytes, err_msg, errnum
        end

        ---@type integer
        local recv_len = bytes:len()

        if recv_len == 0 then
            print("stream closed")
            break
        end

        len_to_read = len_to_read - recv_len
        assert(len_to_read >= 0, "Overread message boundary")

        data = data .. bytes
    end
    return data
end

while true do
    local msg_len_bytes, err_msg, err_num = read_exact(socket_fd, 4)
    assert(msg_len_bytes)

    ---@type integer
    local msg_len = string.unpack("=I4", msg_len_bytes)

    local msg_bytes, err_msg2, err_num2 = read_exact(socket_fd, msg_len)
    assert(msg_bytes)

    local tb = msgpack.decode(msg_bytes)

    if tb.CallCallback then
        CallbackTable[tb.CallCallback]()
    end
end