1 /* mpz_set_str(mp_dest, string, base) -- Convert the \0-terminated 2 string STRING in base BASE to multiple precision integer in 3 MP_DEST. Allow white space in the string. If BASE == 0 determine 4 the base in the C standard way, i.e. 0xhh...h means base 16, 5 0oo...o means base 8, otherwise assume base 10. 6 7 Copyright 1991, 1993, 1994, 1996, 1997, 1998, 2000, 2001, 2002, 2003, 2005 8 Free Software Foundation, Inc. 9 10 This file is part of the GNU MP Library. 11 12 The GNU MP Library is free software; you can redistribute it and/or modify 13 it under the terms of the GNU Lesser General Public License as published by 14 the Free Software Foundation; either version 3 of the License, or (at your 15 option) any later version. 16 17 The GNU MP Library is distributed in the hope that it will be useful, but 18 WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 19 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 20 License for more details. 21 22 You should have received a copy of the GNU Lesser General Public License 23 along with the GNU MP Library. If not, see http://www.gnu.org/licenses/. */ 24 25 #include <string.h> 26 #include <ctype.h> 27 #include "gmp.h" 28 #include "gmp-impl.h" 29 30 extern const unsigned char __gmp_digit_value_tab[]; 31 #define digit_value_tab __gmp_digit_value_tab 32 33 int 34 mpz_set_str (mpz_ptr x, const char *str, int base) 35 { 36 size_t str_size; 37 char *s, *begs; 38 size_t i; 39 mp_size_t xsize; 40 int c; 41 int negative; 42 const unsigned char *digit_value; 43 TMP_DECL; 44 45 digit_value = digit_value_tab; 46 if (base > 36) 47 { 48 /* For bases > 36, use the collating sequence 49 0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz. */ 50 digit_value += 224; 51 if (base > 62) 52 return -1; /* too large base */ 53 } 54 55 /* Skip whitespace. */ 56 do 57 c = (unsigned char) *str++; 58 while (isspace (c)); 59 60 negative = 0; 61 if (c == '-') 62 { 63 negative = 1; 64 c = (unsigned char) *str++; 65 } 66 67 if (digit_value[c] >= (base == 0 ? 10 : base)) 68 return -1; /* error if no valid digits */ 69 70 /* If BASE is 0, try to find out the base by looking at the initial 71 characters. */ 72 if (base == 0) 73 { 74 base = 10; 75 if (c == '0') 76 { 77 base = 8; 78 c = (unsigned char) *str++; 79 if (c == 'x' || c == 'X') 80 { 81 base = 16; 82 c = (unsigned char) *str++; 83 } 84 else if (c == 'b' || c == 'B') 85 { 86 base = 2; 87 c = (unsigned char) *str++; 88 } 89 } 90 } 91 92 /* Skip leading zeros and white space. */ 93 while (c == '0' || isspace (c)) 94 c = (unsigned char) *str++; 95 /* Make sure the string does not become empty, mpn_set_str would fail. */ 96 if (c == 0) 97 { 98 x->_mp_size = 0; 99 return 0; 100 } 101 102 TMP_MARK; 103 str_size = strlen (str - 1); 104 s = begs = (char *) TMP_ALLOC (str_size + 1); 105 106 /* Remove spaces from the string and convert the result from ASCII to a 107 byte array. */ 108 for (i = 0; i < str_size; i++) 109 { 110 if (!isspace (c)) 111 { 112 int dig = digit_value[c]; 113 if (dig >= base) 114 { 115 TMP_FREE; 116 return -1; 117 } 118 *s++ = dig; 119 } 120 c = (unsigned char) *str++; 121 } 122 123 str_size = s - begs; 124 125 xsize = 2 + (mp_size_t) 126 (str_size / (GMP_NUMB_BITS * mp_bases[base].chars_per_bit_exactly)); 127 MPZ_REALLOC (x, xsize); 128 129 /* Convert the byte array in base BASE to our bignum format. */ 130 xsize = mpn_set_str (x->_mp_d, (unsigned char *) begs, str_size, base); 131 x->_mp_size = negative ? -xsize : xsize; 132 133 TMP_FREE; 134 return 0; 135 } 136