/* See LICENSE of license details. */

#include <errno.h>
#include <stdint.h>
#include <sys/types.h>
#include <unistd.h>

#include "platform.h"
#include "semihosting.h"
#include "stub.h"
#include "weak_under_alias.h"

ssize_t __wrap_read(int fd, void *ptr, size_t len) {
  uint8_t *current = (uint8_t *)ptr;
#if defined(SEMIHOSTING)
  int i = sh_read(current, fd, len);
  return i;
#endif
#if defined(BOARD_hifive1)
  volatile uint32_t *uart_rx = (uint32_t *)(UART0_CTRL_ADDR + UART_REG_RXFIFO);
  volatile uint8_t *uart_rx_cnt =
      (uint8_t *)(UART0_CTRL_ADDR + UART_REG_RXCTRL + 2);
#elif defined(BOARD_iss)
  volatile uint32_t *uart_rx = (uint32_t *)0xFFFF0000;
#elif defined(BOARD_TGCP)
  // TODO: implement
#elif !defined(BOARD_ehrenberg) && !defined(BOARD_tgc_vp)
  volatile uint32_t *uart_rx = (uint32_t *)(UART0_BASE_ADDR + UART_REG_RXFIFO);
  volatile uint8_t *uart_rx_cnt =
      (uint8_t *)(UART0_BASE_ADDR + UART_REG_RXCTRL + 2);
#endif
  ssize_t result = 0;
  if (isatty(fd)) {
#if defined(BOARD_ehrenberg) || defined(BOARD_tgc_vp)
    for (current = (uint8_t *)ptr; (current < ((uint8_t *)ptr) + len) &&
                                   (get_uart_rx_tx_reg_rx_avail(uart) > 0);
         current++) {
      *current = uart_read(uart);
      result++;
    }
#elif defined(BOARD_iss)
    for (current = (uint8_t *)ptr; (current < ((uint8_t *)ptr) + len);
         current++) {
      *current = *uart_rx;
      result++;
    }
#elif defined(BOARD_TGCP)
    // TODO: implement
#else
    for (current = (uint8_t *)ptr;
         (current < ((uint8_t *)ptr) + len) && (*uart_rx_cnt > 0); current++) {
      *current = *uart_rx;
      result++;
    }
#endif
    return result;
  }
  return _stub(EBADF);
}
weak_under_alias(read);