Rate Limiting in Assembly Language

; Rate Limiting Example

section .data
    request_msg db 'request %d %s', 0
    time_format db '%Y-%m-%d %H:%M:%S', 0
    newline db 10, 0

section .bss
    time_buffer resb 64

section .text
global _start

_start:
    ; Simulate incoming requests
    mov ecx, 5
    .request_loop:
        push ecx
        call process_request
        pop ecx
        loop .request_loop

    ; Exit program
    mov eax, 1
    xor ebx, ebx
    int 0x80

process_request:
    ; Simulate rate limiting delay
    mov eax, 162         ; nanosleep system call
    push dword 200000000 ; 200 milliseconds
    push dword 0
    mov ebx, esp
    int 0x80
    add esp, 8

    ; Get current time
    mov eax, 13          ; time system call
    xor ebx, ebx
    int 0x80

    ; Convert time to string
    push eax
    push time_format
    push time_buffer
    call strftime
    add esp, 12

    ; Print request message
    push time_buffer
    push dword [esp+8]   ; request number
    push request_msg
    call printf
    add esp, 12

    ; Print newline
    push newline
    call printf
    add esp, 4

    ret

; External C functions
extern printf
extern strftime

This Assembly Language example demonstrates a basic form of rate limiting. Here’s an explanation of how it works:

1. We define some data sections for our messages and a buffer to hold the formatted time.

2. In the _start function, we simulate 5 incoming requests using a loop.

3. For each request, we call the process_request function.

4. In process_request, we first simulate a rate limiting delay using the nanosleep system call. This introduces a 200-millisecond delay between each request processing.

5. We then get the current time using the time system call and convert it to a formatted string using the strftime function.

6. Finally, we print the request message with the request number and the current time using the printf function.

This implementation doesn’t have the sophistication of the Go version with channels and goroutines, as these are high-level concepts not directly available in Assembly. Instead, it provides a simplified demonstration of rate limiting by introducing a fixed delay between request processing.

To run this program, you would need to assemble it, link it with the C standard library (for printf and strftime), and then execute the resulting binary. The output would show each request being processed approximately 200 milliseconds apart.

Note that this is a basic example and real-world rate limiting in Assembly would likely involve more complex timing mechanisms and possibly interrupt-driven approaches, depending on the specific requirements and the target system.