/***********************************************************************/
/*                                                                     */
/*                           Objective Caml                            */
/*                                                                     */
/*            Xavier Leroy, projet Cristal, INRIA Rocquencourt         */
/*                                                                     */
/*  Copyright 1996 Institut National de Recherche en Informatique et   */
/*  en Automatique.  All rights reserved.  This file is distributed    */
/*  under the terms of the GNU Library General Public License, with    */
/*  the special exception on linking described in file ../LICENSE.     */
/*                                                                     */
/***********************************************************************/

/* $Id$ */

#include <stdio.h>
#include <string.h>
#include "alloc.h"
#include "custom.h"
#include "fail.h"
#include "intext.h"
#include "memory.h"
#include "misc.h"
#include "mlvalues.h"

static char * parse_sign_and_base(char * p,
                                  /*out*/ int * base,
                                  /*out*/ int * sign)
{
  *sign = 1;
  if (*p == '-') {
    *sign = -1;
    p++;
  }
  *base = 10;
  if (*p == '0') {
    switch (p[1]) {
    case 'x': case 'X':
      *base = 16; p += 2; break;
    case 'o': case 'O':
      *base = 8; p += 2; break;
    case 'b': case 'B':
      *base = 2; p += 2; break;
    }
  }
  return p;
}

static int parse_digit(char c)
{
  if (c >= '0' && c <= '9')
    return c - '0';
  else if (c >= 'A' && c <= 'F')
    return c - 'A' + 10;
  else if (c >= 'a' && c <= 'f')
    return c - 'a' + 10;
  else
    return -1;
}

static intnat parse_intnat(value s, int nbits)
{
  char * p;
  uintnat res, threshold;
  int sign, base, d;

  p = parse_sign_and_base(String_val(s), &base, &sign);
  threshold = ((uintnat) -1) / base;
  d = parse_digit(*p);
  if (d < 0 || d >= base) caml_failwith("int_of_string");
  for (p++, res = d; /*nothing*/; p++) {
    char c = *p;
    if (c == '_') continue;
    d = parse_digit(c);
    if (d < 0 || d >= base) break;
    /* Detect overflow in multiplication base * res */
    if (res > threshold) caml_failwith("int_of_string");
    res = base * res + d;
    /* Detect overflow in addition (base * res) + d */
    if (res < (uintnat) d) caml_failwith("int_of_string");
  }
  if (p != String_val(s) + caml_string_length(s)){
    caml_failwith("int_of_string");
  }
  if (base == 10) {
    /* Signed representation expected, allow -2^(nbits-1) to 2^(nbits - 1) */
    if (res > (uintnat)1 << (nbits - 1))
      caml_failwith("int_of_string");
  } else {
    /* Unsigned representation expected, allow 0 to 2^nbits - 1
       and tolerate -(2^nbits - 1) to 0 */
    if (nbits < sizeof(uintnat) * 8 && res >= (uintnat)1 << nbits)
      caml_failwith("int_of_string");
  }
  return sign < 0 ? -((intnat) res) : (intnat) res;
}

#ifdef NONSTANDARD_DIV_MOD
intnat caml_safe_div(intnat p, intnat q)
{
  uintnat ap = p >= 0 ? p : -p;
  uintnat aq = q >= 0 ? q : -q;
  uintnat ar = ap / aq;
  return (p ^ q) >= 0 ? ar : -ar;
}

intnat caml_safe_mod(intnat p, intnat q)
{
  uintnat ap = p >= 0 ? p : -p;
  uintnat aq = q >= 0 ? q : -q;
  uintnat ar = ap % aq;
  return p >= 0 ? ar : -ar;
}
#endif

/* Tagged integers */

CAMLprim value caml_int_compare(value v1, value v2)
{
  int res = (v1 > v2) - (v1 < v2);
  return Val_int(res);
}

CAMLprim value caml_int_of_string(value s)
{
  return Val_long(parse_intnat(s, 8 * sizeof(value) - 1));
}

#define FORMAT_BUFFER_SIZE 32

static char * parse_format(value fmt,
                           char * suffix,
                           char format_string[],
                           char default_format_buffer[],
                           char *conv)
{
  int prec;
  char * p;
  char lastletter;
  mlsize_t len, len_suffix;

  /* Copy Caml format fmt to format_string,
     adding the suffix before the last letter of the format */
  len = caml_string_length(fmt);
  len_suffix = strlen(suffix);
  if (len + len_suffix + 1 >= FORMAT_BUFFER_SIZE)
    caml_invalid_argument("format_int: format too long");
  memmove(format_string, String_val(fmt), len);
  p = format_string + len - 1;
  lastletter = *p;
  /* Compress two-letter formats, ignoring the [lnL] annotation */
  if (p[-1] == 'l' || p[-1] == 'n' || p[-1] == 'L') p--;
  memmove(p, suffix, len_suffix);  p += len_suffix;
  *p++ = lastletter;
  *p = 0;
  /* Determine space needed for result and allocate it dynamically if needed */
  prec = 22 + 5; /* 22 digits for 64-bit number in octal + 5 extra */
  for (p = String_val(fmt); *p != 0; p++) {
    if (*p >= '0' && *p <= '9') {
      prec = atoi(p) + 5;
      break;
    }
  }
  *conv = lastletter;
  if (prec < FORMAT_BUFFER_SIZE)
    return default_format_buffer;
  else
    return caml_stat_alloc(prec + 1);
}

CAMLprim value caml_format_int(value fmt, value arg)
{
  char format_string[FORMAT_BUFFER_SIZE];
  char default_format_buffer[FORMAT_BUFFER_SIZE];
  char * buffer;
  char conv;
  value res;

  buffer = parse_format(fmt, ARCH_INTNAT_PRINTF_FORMAT,
			format_string, default_format_buffer, &conv);
  switch (conv) {
  case 'u': case 'x': case 'X': case 'o':
    sprintf(buffer, format_string, Unsigned_long_val(arg));
    break;
  default:
    sprintf(buffer, format_string, Long_val(arg));
    break;
  }
  res = caml_copy_string(buffer);
  if (buffer != default_format_buffer) caml_stat_free(buffer);
  return res;
}

/* 32-bit integers */

static int int32_cmp(value v1, value v2)
{
  int32 i1 = Int32_val(v1);
  int32 i2 = Int32_val(v2);
  return (i1 > i2) - (i1 < i2);
}

static intnat int32_hash(value v)
{
  return Int32_val(v);
}

static void int32_serialize(value v, uintnat * wsize_32,
                            uintnat * wsize_64)
{
  caml_serialize_int_4(Int32_val(v));
  *wsize_32 = *wsize_64 = 4;
}

static uintnat int32_deserialize(void * dst)
{
  *((int32 *) dst) = caml_deserialize_sint_4();
  return 4;
}

CAMLexport struct custom_operations caml_int32_ops = {
  "_i",
  custom_finalize_default,
  int32_cmp,
  int32_hash,
  int32_serialize,
  int32_deserialize
};

CAMLexport value caml_copy_int32(int32 i)
{
  value res = caml_alloc_custom(&caml_int32_ops, 4, 0, 1);
  Int32_val(res) = i;
  return res;
}

CAMLprim value caml_int32_neg(value v)
{ return caml_copy_int32(- Int32_val(v)); }

CAMLprim value caml_int32_add(value v1, value v2)
{ return caml_copy_int32(Int32_val(v1) + Int32_val(v2)); }

CAMLprim value caml_int32_sub(value v1, value v2)
{ return caml_copy_int32(Int32_val(v1) - Int32_val(v2)); }

CAMLprim value caml_int32_mul(value v1, value v2)
{ return caml_copy_int32(Int32_val(v1) * Int32_val(v2)); }

CAMLprim value caml_int32_div(value v1, value v2)
{
  int32 divisor = Int32_val(v2);
  if (divisor == 0) caml_raise_zero_divide();
#ifdef NONSTANDARD_DIV_MOD
  return caml_copy_int32(caml_safe_div(Int32_val(v1), divisor));
#else
  return caml_copy_int32(Int32_val(v1) / divisor);
#endif
}

CAMLprim value caml_int32_mod(value v1, value v2)
{
  int32 divisor = Int32_val(v2);
  if (divisor == 0) caml_raise_zero_divide();
#ifdef NONSTANDARD_DIV_MOD
  return caml_copy_int32(caml_safe_mod(Int32_val(v1), divisor));
#else
  return caml_copy_int32(Int32_val(v1) % divisor);
#endif
}

CAMLprim value caml_int32_and(value v1, value v2)
{ return caml_copy_int32(Int32_val(v1) & Int32_val(v2)); }

CAMLprim value caml_int32_or(value v1, value v2)
{ return caml_copy_int32(Int32_val(v1) | Int32_val(v2)); }

CAMLprim value caml_int32_xor(value v1, value v2)
{ return caml_copy_int32(Int32_val(v1) ^ Int32_val(v2)); }

CAMLprim value caml_int32_shift_left(value v1, value v2)
{ return caml_copy_int32(Int32_val(v1) << Int_val(v2)); }

CAMLprim value caml_int32_shift_right(value v1, value v2)
{ return caml_copy_int32(Int32_val(v1) >> Int_val(v2)); }

CAMLprim value caml_int32_shift_right_unsigned(value v1, value v2)
{ return caml_copy_int32((uint32)Int32_val(v1) >> Int_val(v2)); }

CAMLprim value caml_int32_of_int(value v)
{ return caml_copy_int32(Long_val(v)); }

CAMLprim value caml_int32_to_int(value v)
{ return Val_long(Int32_val(v)); }

CAMLprim value caml_int32_of_float(value v)
{ return caml_copy_int32((int32)(Double_val(v))); }

CAMLprim value caml_int32_to_float(value v)
{ return caml_copy_double((double)(Int32_val(v))); }

CAMLprim value caml_int32_compare(value v1, value v2)
{
  int32 i1 = Int32_val(v1);
  int32 i2 = Int32_val(v2);
  int res = (i1 > i2) - (i1 < i2);
  return Val_int(res);
}

CAMLprim value caml_int32_format(value fmt, value arg)
{
  char format_string[FORMAT_BUFFER_SIZE];
  char default_format_buffer[FORMAT_BUFFER_SIZE];
  char * buffer;
  char conv;
  value res;

  buffer = parse_format(fmt, ARCH_INT32_PRINTF_FORMAT,
                        format_string, default_format_buffer, &conv);
  sprintf(buffer, format_string, Int32_val(arg));
  res = caml_copy_string(buffer);
  if (buffer != default_format_buffer) caml_stat_free(buffer);
  return res;
}

CAMLprim value caml_int32_of_string(value s)
{
  return caml_copy_int32(parse_intnat(s, 32));
}

CAMLprim value caml_int32_bits_of_float(value vd)
{
  union { float d; int32 i; } u;
  u.d = Double_val(vd);
  return caml_copy_int32(u.i);
}

CAMLprim value caml_int32_float_of_bits(value vi)
{
  union { float d; int32 i; } u;
  u.i = Int32_val(vi);
  return caml_copy_double(u.d);
}

/* 64-bit integers */

#ifdef ARCH_INT64_TYPE
#include "int64_native.h"
#else
#include "int64_emul.h"
#endif

#ifdef ARCH_ALIGN_INT64

CAMLexport int64 caml_Int64_val(value v)
{
  union { int32 i[2]; int64 j; } buffer;
  buffer.i[0] = ((int32 *) Data_custom_val(v))[0];
  buffer.i[1] = ((int32 *) Data_custom_val(v))[1];
  return buffer.j;
}

#endif

static int int64_cmp(value v1, value v2)
{
  int64 i1 = Int64_val(v1);
  int64 i2 = Int64_val(v2);
  return I64_compare(i1, i2);
}

static intnat int64_hash(value v)
{
  return I64_to_intnat(Int64_val(v));
}

static void int64_serialize(value v, uintnat * wsize_32,
                            uintnat * wsize_64)
{
  caml_serialize_int_8(Int64_val(v));
  *wsize_32 = *wsize_64 = 8;
}

static uintnat int64_deserialize(void * dst)
{
#ifndef ARCH_ALIGN_INT64
  *((int64 *) dst) = caml_deserialize_sint_8();
#else
  union { int32 i[2]; int64 j; } buffer;
  buffer.j = caml_deserialize_sint_8();
  ((int32 *) dst)[0] = buffer.i[0];
  ((int32 *) dst)[1] = buffer.i[1];
#endif
  return 8;
}

CAMLexport struct custom_operations caml_int64_ops = {
  "_j",
  custom_finalize_default,
  int64_cmp,
  int64_hash,
  int64_serialize,
  int64_deserialize
};

CAMLexport value caml_copy_int64(int64 i)
{
  value res = caml_alloc_custom(&caml_int64_ops, 8, 0, 1);
#ifndef ARCH_ALIGN_INT64
  Int64_val(res) = i;
#else
  union { int32 i[2]; int64 j; } buffer;
  buffer.j = i;
  ((int32 *) Data_custom_val(res))[0] = buffer.i[0];
  ((int32 *) Data_custom_val(res))[1] = buffer.i[1];
#endif
  return res;
}

CAMLprim value caml_int64_neg(value v)
{ return caml_copy_int64(I64_neg(Int64_val(v))); }

CAMLprim value caml_int64_add(value v1, value v2)
{ return caml_copy_int64(I64_add(Int64_val(v1), Int64_val(v2))); }

CAMLprim value caml_int64_sub(value v1, value v2)
{ return caml_copy_int64(I64_sub(Int64_val(v1), Int64_val(v2))); }

CAMLprim value caml_int64_mul(value v1, value v2)
{ return caml_copy_int64(I64_mul(Int64_val(v1), Int64_val(v2))); }

CAMLprim value caml_int64_div(value v1, value v2)
{
  int64 divisor = Int64_val(v2);
  if (I64_is_zero(divisor)) caml_raise_zero_divide();
  return caml_copy_int64(I64_div(Int64_val(v1), divisor));
}

CAMLprim value caml_int64_mod(value v1, value v2)
{
  int64 divisor = Int64_val(v2);
  if (I64_is_zero(divisor)) caml_raise_zero_divide();
  return caml_copy_int64(I64_mod(Int64_val(v1), divisor));
}

CAMLprim value caml_int64_and(value v1, value v2)
{ return caml_copy_int64(I64_and(Int64_val(v1), Int64_val(v2))); }

CAMLprim value caml_int64_or(value v1, value v2)
{ return caml_copy_int64(I64_or(Int64_val(v1), Int64_val(v2))); }

CAMLprim value caml_int64_xor(value v1, value v2)
{ return caml_copy_int64(I64_xor(Int64_val(v1), Int64_val(v2))); }

CAMLprim value caml_int64_shift_left(value v1, value v2)
{ return caml_copy_int64(I64_lsl(Int64_val(v1), Int_val(v2))); }

CAMLprim value caml_int64_shift_right(value v1, value v2)
{ return caml_copy_int64(I64_asr(Int64_val(v1), Int_val(v2))); }

CAMLprim value caml_int64_shift_right_unsigned(value v1, value v2)
{ return caml_copy_int64(I64_lsr(Int64_val(v1), Int_val(v2))); }

CAMLprim value caml_int64_of_int(value v)
{ return caml_copy_int64(I64_of_intnat(Long_val(v))); }

CAMLprim value caml_int64_to_int(value v)
{ return Val_long(I64_to_intnat(Int64_val(v))); }

CAMLprim value caml_int64_of_float(value v)
{ return caml_copy_int64(I64_of_double(Double_val(v))); }

CAMLprim value caml_int64_to_float(value v)
{ 
  int64 i = Int64_val(v);
  return caml_copy_double(I64_to_double(i));
}

CAMLprim value caml_int64_of_int32(value v)
{ return caml_copy_int64(I64_of_int32(Int32_val(v))); }

CAMLprim value caml_int64_to_int32(value v)
{ return caml_copy_int32(I64_to_int32(Int64_val(v))); }

CAMLprim value caml_int64_of_nativeint(value v)
{ return caml_copy_int64(I64_of_intnat(Nativeint_val(v))); }

CAMLprim value caml_int64_to_nativeint(value v)
{ return caml_copy_nativeint(I64_to_intnat(Int64_val(v))); }

CAMLprim value caml_int64_compare(value v1, value v2)
{
  int64 i1 = Int64_val(v1);
  int64 i2 = Int64_val(v2);
  return Val_int(I64_compare(i1, i2));
}

#ifdef ARCH_INT64_PRINTF_FORMAT
#define I64_format(buf,fmt,x) sprintf(buf,fmt,x)
#else
#include "int64_format.h"
#define ARCH_INT64_PRINTF_FORMAT ""
#endif

CAMLprim value caml_int64_format(value fmt, value arg)
{
  char format_string[FORMAT_BUFFER_SIZE];
  char default_format_buffer[FORMAT_BUFFER_SIZE];
  char * buffer;
  char conv;
  value res;

  buffer = parse_format(fmt, ARCH_INT64_PRINTF_FORMAT,
                        format_string, default_format_buffer, &conv);
  I64_format(buffer, format_string, Int64_val(arg));
  res = caml_copy_string(buffer);
  if (buffer != default_format_buffer) caml_stat_free(buffer);
  return res;
}

CAMLprim value caml_int64_of_string(value s)
{
  char * p;
  uint64 max_uint64 = I64_literal(0xFFFFFFFF, 0xFFFFFFFF);
  uint64 max_int64  = I64_literal(0x80000000, 0x00000000);
  uint64 res, threshold;
  int sign, base, d;

  p = parse_sign_and_base(String_val(s), &base, &sign);
  I64_udivmod(max_uint64, I64_of_int32(base), &threshold, &res);
  d = parse_digit(*p);
  if (d < 0 || d >= base) caml_failwith("int_of_string");
  res = I64_of_int32(d);
  for (p++; /*nothing*/; p++) {
    char c = *p;
    if (c == '_') continue;
    d = parse_digit(c);
    if (d < 0 || d >= base) break;
    /* Detect overflow in multiplication base * res */
    if (I64_ult(threshold, res)) caml_failwith("int_of_string");
    res = I64_add(I64_mul(I64_of_int32(base), res), I64_of_int32(d));
    /* Detect overflow in addition (base * res) + d */
    if (I64_ult(res, I64_of_int32(d))) caml_failwith("int_of_string");
  }
  if (p != String_val(s) + caml_string_length(s)){
    caml_failwith("int_of_string");
  }
  if (base == 10 && I64_ult(max_int64, res)) caml_failwith("int_of_string");
  if (sign < 0) res = I64_neg(res);
  return caml_copy_int64(res);
}

CAMLprim value caml_int64_bits_of_float(value vd)
{
  union { double d; int64 i; } u;
  u.d = Double_val(vd);
  return caml_copy_int64(u.i);
}

CAMLprim value caml_int64_float_of_bits(value vi)
{
  union { double d; int64 i; } u;
  u.i = Int64_val(vi);
  return caml_copy_double(u.d);
}

/* Native integers */

static int nativeint_cmp(value v1, value v2)
{
  intnat i1 = Nativeint_val(v1);
  intnat i2 = Nativeint_val(v2);
  return (i1 > i2) - (i1 < i2);
}

static intnat nativeint_hash(value v)
{
  return Nativeint_val(v);
}

static void nativeint_serialize(value v, uintnat * wsize_32,
                                uintnat * wsize_64)
{
  intnat l = Nativeint_val(v);
#ifdef ARCH_SIXTYFOUR
  if (l <= 0x7FFFFFFFL && l >= -0x80000000L) {
    caml_serialize_int_1(1);
    caml_serialize_int_4((int32) l);
  } else {
    caml_serialize_int_1(2);
    caml_serialize_int_8(l);
  }
#else
  caml_serialize_int_1(1);
  caml_serialize_int_4(l);
#endif
  *wsize_32 = 4;
  *wsize_64 = 8;
}

static uintnat nativeint_deserialize(void * dst)
{
  switch (caml_deserialize_uint_1()) {
  case 1:
    *((intnat *) dst) = caml_deserialize_sint_4();
    break;
  case 2:
#ifdef ARCH_SIXTYFOUR
    *((intnat *) dst) = caml_deserialize_sint_8();
#else
    caml_deserialize_error("input_value: native integer value too large");
#endif
    break;
  default:
    caml_deserialize_error("input_value: ill-formed native integer");
  }
  return sizeof(long);
}

CAMLexport struct custom_operations caml_nativeint_ops = {
  "_n",
  custom_finalize_default,
  nativeint_cmp,
  nativeint_hash,
  nativeint_serialize,
  nativeint_deserialize
};

CAMLexport value caml_copy_nativeint(intnat i)
{
  value res = caml_alloc_custom(&caml_nativeint_ops, sizeof(intnat), 0, 1);
  Nativeint_val(res) = i;
  return res;
}

CAMLprim value caml_nativeint_neg(value v)
{ return caml_copy_nativeint(- Nativeint_val(v)); }

CAMLprim value caml_nativeint_add(value v1, value v2)
{ return caml_copy_nativeint(Nativeint_val(v1) + Nativeint_val(v2)); }

CAMLprim value caml_nativeint_sub(value v1, value v2)
{ return caml_copy_nativeint(Nativeint_val(v1) - Nativeint_val(v2)); }

CAMLprim value caml_nativeint_mul(value v1, value v2)
{ return caml_copy_nativeint(Nativeint_val(v1) * Nativeint_val(v2)); }

CAMLprim value caml_nativeint_div(value v1, value v2)
{
  intnat divisor = Nativeint_val(v2);
  if (divisor == 0) caml_raise_zero_divide();
#ifdef NONSTANDARD_DIV_MOD
  return caml_copy_nativeint(caml_safe_div(Nativeint_val(v1), divisor));
#else
  return caml_copy_nativeint(Nativeint_val(v1) / divisor);
#endif
}

CAMLprim value caml_nativeint_mod(value v1, value v2)
{
  intnat divisor = Nativeint_val(v2);
  if (divisor == 0) caml_raise_zero_divide();
#ifdef NONSTANDARD_DIV_MOD
  return caml_copy_nativeint(caml_safe_mod(Nativeint_val(v1), divisor));
#else
  return caml_copy_nativeint(Nativeint_val(v1) % divisor);
#endif
}

CAMLprim value caml_nativeint_and(value v1, value v2)
{ return caml_copy_nativeint(Nativeint_val(v1) & Nativeint_val(v2)); }

CAMLprim value caml_nativeint_or(value v1, value v2)
{ return caml_copy_nativeint(Nativeint_val(v1) | Nativeint_val(v2)); }

CAMLprim value caml_nativeint_xor(value v1, value v2)
{ return caml_copy_nativeint(Nativeint_val(v1) ^ Nativeint_val(v2)); }

CAMLprim value caml_nativeint_shift_left(value v1, value v2)
{ return caml_copy_nativeint(Nativeint_val(v1) << Int_val(v2)); }

CAMLprim value caml_nativeint_shift_right(value v1, value v2)
{ return caml_copy_nativeint(Nativeint_val(v1) >> Int_val(v2)); }

CAMLprim value caml_nativeint_shift_right_unsigned(value v1, value v2)
{ return caml_copy_nativeint((uintnat)Nativeint_val(v1) >> Int_val(v2)); }

CAMLprim value caml_nativeint_of_int(value v)
{ return caml_copy_nativeint(Long_val(v)); }

CAMLprim value caml_nativeint_to_int(value v)
{ return Val_long(Nativeint_val(v)); }

CAMLprim value caml_nativeint_of_float(value v)
{ return caml_copy_nativeint((intnat)(Double_val(v))); }

CAMLprim value caml_nativeint_to_float(value v)
{ return caml_copy_double((double)(Nativeint_val(v))); }

CAMLprim value caml_nativeint_of_int32(value v)
{ return caml_copy_nativeint(Int32_val(v)); }

CAMLprim value caml_nativeint_to_int32(value v)
{ return caml_copy_int32(Nativeint_val(v)); }

CAMLprim value caml_nativeint_compare(value v1, value v2)
{
  intnat i1 = Nativeint_val(v1);
  intnat i2 = Nativeint_val(v2);
  int res = (i1 > i2) - (i1 < i2);
  return Val_int(res);
}

CAMLprim value caml_nativeint_format(value fmt, value arg)
{
  char format_string[FORMAT_BUFFER_SIZE];
  char default_format_buffer[FORMAT_BUFFER_SIZE];
  char * buffer;
  char conv;
  value res;

  buffer = parse_format(fmt, ARCH_INTNAT_PRINTF_FORMAT,
                        format_string, default_format_buffer, &conv);
  sprintf(buffer, format_string, Nativeint_val(arg));
  res = caml_copy_string(buffer);
  if (buffer != default_format_buffer) caml_stat_free(buffer);
  return res;
}

CAMLprim value caml_nativeint_of_string(value s)
{
  return caml_copy_nativeint(parse_intnat(s, 8 * sizeof(value)));
}