1 /* mpz_out_raw -- write an mpz_t in raw format. 2 3 Copyright 2001, 2002 Free Software Foundation, Inc. 4 5 This file is part of the GNU MP Library. 6 7 The GNU MP Library is free software; you can redistribute it and/or modify 8 it under the terms of either: 9 10 * the GNU Lesser General Public License as published by the Free 11 Software Foundation; either version 3 of the License, or (at your 12 option) any later version. 13 14 or 15 16 * the GNU General Public License as published by the Free Software 17 Foundation; either version 2 of the License, or (at your option) any 18 later version. 19 20 or both in parallel, as here. 21 22 The GNU MP Library is distributed in the hope that it will be useful, but 23 WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 24 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 25 for more details. 26 27 You should have received copies of the GNU General Public License and the 28 GNU Lesser General Public License along with the GNU MP Library. If not, 29 see https://www.gnu.org/licenses/. */ 30 31 #include <stdio.h> 32 #include "gmp.h" 33 #include "gmp-impl.h" 34 #include "longlong.h" 35 36 37 /* HTON_LIMB_STORE takes a normal host byte order limb and stores it as 38 network byte order (ie. big endian). */ 39 40 #if HAVE_LIMB_BIG_ENDIAN 41 #define HTON_LIMB_STORE(dst, limb) do { *(dst) = (limb); } while (0) 42 #endif 43 44 #if HAVE_LIMB_LITTLE_ENDIAN 45 #define HTON_LIMB_STORE(dst, limb) BSWAP_LIMB_STORE (dst, limb) 46 #endif 47 48 #ifndef HTON_LIMB_STORE 49 #define HTON_LIMB_STORE(dst, limb) \ 50 do { \ 51 mp_limb_t __limb = (limb); \ 52 char *__p = (char *) (dst); \ 53 int __i; \ 54 for (__i = 0; __i < GMP_LIMB_BYTES; __i++) \ 55 __p[__i] = (char) (__limb >> ((GMP_LIMB_BYTES-1 - __i) * 8)); \ 56 } while (0) 57 #endif 58 59 60 size_t 61 mpz_out_raw (FILE *fp, mpz_srcptr x) 62 { 63 mp_size_t xsize, abs_xsize, bytes, i; 64 mp_srcptr xp; 65 char *tp, *bp; 66 mp_limb_t xlimb; 67 int zeros; 68 size_t tsize, ssize; 69 70 xsize = SIZ(x); 71 abs_xsize = ABS (xsize); 72 bytes = (abs_xsize * GMP_NUMB_BITS + 7) / 8; 73 tsize = ROUND_UP_MULTIPLE ((unsigned) 4, GMP_LIMB_BYTES) + bytes; 74 75 tp = __GMP_ALLOCATE_FUNC_TYPE (tsize, char); 76 bp = tp + ROUND_UP_MULTIPLE ((unsigned) 4, GMP_LIMB_BYTES); 77 78 if (bytes != 0) 79 { 80 bp += bytes; 81 xp = PTR (x); 82 i = abs_xsize; 83 84 if (GMP_NAIL_BITS == 0) 85 { 86 /* reverse limb order, and byte swap if necessary */ 87 #ifdef _CRAY 88 _Pragma ("_CRI ivdep"); 89 #endif 90 do 91 { 92 bp -= GMP_LIMB_BYTES; 93 xlimb = *xp; 94 HTON_LIMB_STORE ((mp_ptr) bp, xlimb); 95 xp++; 96 } 97 while (--i > 0); 98 99 /* strip high zero bytes (without fetching from bp) */ 100 count_leading_zeros (zeros, xlimb); 101 zeros /= 8; 102 bp += zeros; 103 bytes -= zeros; 104 } 105 else 106 { 107 mp_limb_t new_xlimb; 108 int bits; 109 ASSERT_CODE (char *bp_orig = bp - bytes); 110 111 ASSERT_ALWAYS (GMP_NUMB_BITS >= 8); 112 113 bits = 0; 114 xlimb = 0; 115 for (;;) 116 { 117 while (bits >= 8) 118 { 119 ASSERT (bp > bp_orig); 120 *--bp = xlimb & 0xFF; 121 xlimb >>= 8; 122 bits -= 8; 123 } 124 125 if (i == 0) 126 break; 127 128 new_xlimb = *xp++; 129 i--; 130 ASSERT (bp > bp_orig); 131 *--bp = (xlimb | (new_xlimb << bits)) & 0xFF; 132 xlimb = new_xlimb >> (8 - bits); 133 bits += GMP_NUMB_BITS - 8; 134 } 135 136 if (bits != 0) 137 { 138 ASSERT (bp > bp_orig); 139 *--bp = xlimb; 140 } 141 142 ASSERT (bp == bp_orig); 143 while (*bp == 0) 144 { 145 bp++; 146 bytes--; 147 } 148 } 149 } 150 151 /* total bytes to be written */ 152 ssize = 4 + bytes; 153 154 /* twos complement negative for the size value */ 155 bytes = (xsize >= 0 ? bytes : -bytes); 156 157 /* so we don't rely on sign extension in ">>" */ 158 ASSERT_ALWAYS (sizeof (bytes) >= 4); 159 160 bp[-4] = bytes >> 24; 161 bp[-3] = bytes >> 16; 162 bp[-2] = bytes >> 8; 163 bp[-1] = bytes; 164 bp -= 4; 165 166 if (fp == 0) 167 fp = stdout; 168 if (fwrite (bp, ssize, 1, fp) != 1) 169 ssize = 0; 170 171 (*__gmp_free_func) (tp, tsize); 172 return ssize; 173 } 174