// Copyright 2016 The Fuchsia Authors
// Copyright (c) 2008-2015 Travis Geiselbrecht
//
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file or at
// https://opensource.org/licenses/MIT

#include "debug.h"

#include <align.h>
#include <ctype.h>
#include <platform.h>
#include <stdio.h>
#include <stdlib.h>
#include <zircon/boot/crash-reason.h>
#include <zircon/listnode.h>
#include <zircon/time.h>
#include <zircon/types.h>

#include <arch/ops.h>
#include <dev/hw_rng.h>
#include <kernel/spinlock.h>
#include <ktl/algorithm.h>
#include <platform/debug.h>

void spin(uint32_t usecs) {
  zx_time_t start = current_time();

  zx_duration_t nsecs = ZX_USEC(usecs);
  while (zx_time_sub_time(current_time(), start) < nsecs)
    ;
}

void _panic(void* caller, void* frame, const char* fmt, ...) {
  platform_panic_start();

  printf("panic (caller %p frame %p): ", caller, frame);

  va_list ap;
  va_start(ap, fmt);
  vprintf(fmt, ap);
  va_end(ap);

  platform_halt(HALT_ACTION_HALT, ZirconCrashReason::Panic);
}

void _panic_no_format(const char* msg, size_t len) {
  platform_panic_start();
  stdout->Write({msg, len});
  platform_halt(HALT_ACTION_HALT, ZirconCrashReason::Panic);
}

__NO_SAFESTACK uintptr_t choose_stack_guard(void) {
  uintptr_t guard;
  if (hw_rng_get_entropy(&guard, sizeof(guard)) != sizeof(guard)) {
    // We can't get a random value, so use a randomish value.
    guard = 0xdeadbeef00ff00ffUL ^ (uintptr_t)&guard;
  }
  return guard;
}

#if !DISABLE_DEBUG_OUTPUT

void hexdump_very_ex(const void* ptr, size_t len, uint64_t disp_addr, hexdump_print_fn_t* pfn) {
  uintptr_t address = (uintptr_t)ptr;
  size_t count;

  int zero_line_count = 0;
  for (count = 0; count < len; count += 16, address += 16) {
    union {
      uint32_t buf[4];
      uint8_t cbuf[16];
    } u;
    size_t s = ROUNDUP(ktl::min(len - count, size_t{16}), 4);
    size_t i;

    bool cur_line_zeros = true;
    for (i = 0; i < s / 4; i++) {
      cur_line_zeros &= (((const uint32_t*)address)[i] == 0);
    }
    if (cur_line_zeros) {
      zero_line_count++;
      if ((count + 16) >= len) {
        // print the last line normally
      } else if (zero_line_count >= 2) {
        if (zero_line_count == 2) {
          pfn(".....\n");
        }
        continue;
      }
    } else {
      zero_line_count = 0;
    }

    pfn(((disp_addr + len) > 0xFFFFFFFF) ? "0x%016llx: " : "0x%08llx: ", disp_addr + count);

    for (i = 0; i < s / 4; i++) {
      u.buf[i] = ((const uint32_t*)address)[i];
      pfn("%08x ", u.buf[i]);
    }
    for (; i < 4; i++) {
      pfn("         ");
    }
    pfn("|");

    for (i = 0; i < 16; i++) {
      char c = u.cbuf[i];
      if (i < s && isprint(c)) {
        pfn("%c", c);
      } else {
        pfn(".");
      }
    }
    pfn("|\n");
  }
}

void hexdump8_very_ex(const void* ptr, size_t len, uint64_t disp_addr, hexdump_print_fn_t* pfn) {
  uintptr_t address = (uintptr_t)ptr;
  size_t count;
  size_t i;

  int zero_line_count = 0;
  for (count = 0; count < len; count += 16, address += 16) {
    bool cur_line_zeros = true;
    for (i = 0; i < ktl::min(len - count, size_t{16}); i++) {
      cur_line_zeros &= (((const uint8_t*)address)[i] == 0);
    }
    if (cur_line_zeros) {
      zero_line_count++;
      if ((count + 16) >= len) {
        // print the last line normally
      } else if (zero_line_count >= 2) {
        if (zero_line_count == 2) {
          pfn(".....\n");
        }
        continue;
      }
    } else {
      zero_line_count = 0;
    }

    pfn(((disp_addr + len) > 0xFFFFFFFF) ? "0x%016llx: " : "0x%08llx: ", disp_addr + count);

    for (i = 0; i < ktl::min(len - count, size_t{16}); i++) {
      pfn("%02hhx ", *(const uint8_t*)(address + i));
    }

    for (; i < 16; i++) {
      pfn("   ");
    }

    pfn("|");

    for (i = 0; i < ktl::min(len - count, size_t{16}); i++) {
      char c = ((const char*)address)[i];
      pfn("%c", isprint(c) ? c : '.');
    }

    pfn("\n");
  }
}

#endif  // !DISABLE_DEBUG_OUTPUT