1 /*************************************************************************** 2 * _ _ ____ _ 3 * Project ___| | | | _ \| | 4 * / __| | | | |_) | | 5 * | (__| |_| | _ <| |___ 6 * \___|\___/|_| \_\_____| 7 * 8 * Copyright (C) 1998 - 2011, Daniel Stenberg, <daniel (at) haxx.se>, et al. 9 * 10 * This software is licensed as described in the file COPYING, which 11 * you should have received as part of this distribution. The terms 12 * are also available at https://curl.haxx.se/docs/copyright.html. 13 * 14 * You may opt to use, copy, modify, merge, publish, distribute and/or sell 15 * copies of the Software, and permit persons to whom the Software is 16 * furnished to do so, under the terms of the COPYING file. 17 * 18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY 19 * KIND, either express or implied. 20 * 21 ***************************************************************************/ 22 23 #include "curl_setup.h" 24 25 #include "strtoofft.h" 26 27 /* 28 * NOTE: 29 * 30 * In the ISO C standard (IEEE Std 1003.1), there is a strtoimax() function we 31 * could use in case strtoll() doesn't exist... See 32 * http://www.opengroup.org/onlinepubs/009695399/functions/strtoimax.html 33 */ 34 35 #ifdef NEED_CURL_STRTOLL 36 37 /* Range tests can be used for alphanum decoding if characters are consecutive, 38 like in ASCII. Else an array is scanned. Determine this condition now. */ 39 40 #if('9' - '0') != 9 || ('Z' - 'A') != 25 || ('z' - 'a') != 25 41 42 #define NO_RANGE_TEST 43 44 static const char valchars[] = 45 "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"; 46 #endif 47 48 static int get_char(char c, int base); 49 50 /** 51 * Emulated version of the strtoll function. This extracts a long long 52 * value from the given input string and returns it. 53 */ 54 curl_off_t 55 curlx_strtoll(const char *nptr, char **endptr, int base) 56 { 57 char *end; 58 int is_negative = 0; 59 int overflow; 60 int i; 61 curl_off_t value = 0; 62 curl_off_t newval; 63 64 /* Skip leading whitespace. */ 65 end = (char *)nptr; 66 while(ISSPACE(end[0])) { 67 end++; 68 } 69 70 /* Handle the sign, if any. */ 71 if(end[0] == '-') { 72 is_negative = 1; 73 end++; 74 } 75 else if(end[0] == '+') { 76 end++; 77 } 78 else if(end[0] == '\0') { 79 /* We had nothing but perhaps some whitespace -- there was no number. */ 80 if(endptr) { 81 *endptr = end; 82 } 83 return 0; 84 } 85 86 /* Handle special beginnings, if present and allowed. */ 87 if(end[0] == '0' && end[1] == 'x') { 88 if(base == 16 || base == 0) { 89 end += 2; 90 base = 16; 91 } 92 } 93 else if(end[0] == '0') { 94 if(base == 8 || base == 0) { 95 end++; 96 base = 8; 97 } 98 } 99 100 /* Matching strtol, if the base is 0 and it doesn't look like 101 * the number is octal or hex, we assume it's base 10. 102 */ 103 if(base == 0) { 104 base = 10; 105 } 106 107 /* Loop handling digits. */ 108 value = 0; 109 overflow = 0; 110 for(i = get_char(end[0], base); 111 i != -1; 112 end++, i = get_char(end[0], base)) { 113 newval = base * value + i; 114 if(newval < value) { 115 /* We've overflowed. */ 116 overflow = 1; 117 break; 118 } 119 else 120 value = newval; 121 } 122 123 if(!overflow) { 124 if(is_negative) { 125 /* Fix the sign. */ 126 value *= -1; 127 } 128 } 129 else { 130 if(is_negative) 131 value = CURL_OFF_T_MIN; 132 else 133 value = CURL_OFF_T_MAX; 134 135 SET_ERRNO(ERANGE); 136 } 137 138 if(endptr) 139 *endptr = end; 140 141 return value; 142 } 143 144 /** 145 * Returns the value of c in the given base, or -1 if c cannot 146 * be interpreted properly in that base (i.e., is out of range, 147 * is a null, etc.). 148 * 149 * @param c the character to interpret according to base 150 * @param base the base in which to interpret c 151 * 152 * @return the value of c in base, or -1 if c isn't in range 153 */ 154 static int get_char(char c, int base) 155 { 156 #ifndef NO_RANGE_TEST 157 int value = -1; 158 if(c <= '9' && c >= '0') { 159 value = c - '0'; 160 } 161 else if(c <= 'Z' && c >= 'A') { 162 value = c - 'A' + 10; 163 } 164 else if(c <= 'z' && c >= 'a') { 165 value = c - 'a' + 10; 166 } 167 #else 168 const char * cp; 169 int value; 170 171 cp = memchr(valchars, c, 10 + 26 + 26); 172 173 if(!cp) 174 return -1; 175 176 value = cp - valchars; 177 178 if(value >= 10 + 26) 179 value -= 26; /* Lowercase. */ 180 #endif 181 182 if(value >= base) { 183 value = -1; 184 } 185 186 return value; 187 } 188 #endif /* Only present if we need strtoll, but don't have it. */ 189