linux-user/arm/semihost.c

   1 /*
   2  * ARM Semihosting Console Support
   3  *
   4  * Copyright (c) 2019 Linaro Ltd
   5  *
   6  * Currently ARM is unique in having support for semihosting support
   7  * in linux-user. So for now we implement the common console API but
   8  * just for arm linux-user.
   9  *
  10  * SPDX-License-Identifier: GPL-2.0-or-later
  11  */
  12
  13 #include "qemu/osdep.h"
  14 #include "cpu.h"
  15 #include "hw/semihosting/console.h"
  16 #include "qemu.h"
  17
  18 int qemu_semihosting_console_outs(CPUArchState *env, target_ulong addr)
  19 {
  20     int len = target_strlen(addr);
  21     void *s;
  22     if (len < 0){
  23        qemu_log_mask(LOG_GUEST_ERROR,
  24                      "%s: passed inaccessible address " TARGET_FMT_lx,
  25                      __func__, addr);
  26        return 0;
  27     }
  28     s = lock_user(VERIFY_READ, addr, (long)(len + 1), 1);
  29     g_assert(s);  /* target_strlen has already verified this will work */
  30     len = write(STDERR_FILENO, s, len);
  31     unlock_user(s, addr, 0);
  32     return len;
  33 }
  34
  35 void qemu_semihosting_console_outc(CPUArchState *env, target_ulong addr)
  36 {
  37     char c;
  38
  39     if (get_user_u8(c, addr)) {
  40         qemu_log_mask(LOG_GUEST_ERROR,
  41                       "%s: passed inaccessible address " TARGET_FMT_lx,
  42                       __func__, addr);
  43     } else {
  44         if (write(STDERR_FILENO, &c, 1) != 1) {
  45             qemu_log_mask(LOG_UNIMP, "%s: unexpected write to stdout failure",
  46                           __func__);
  47         }
  48     }
  49 }