1 /*************************************************************************** 2 * _ _ ____ _ 3 * Project ___| | | | _ \| | 4 * / __| | | | |_) | | 5 * | (__| |_| | _ <| |___ 6 * \___|\___/|_| \_\_____| 7 * 8 * Copyright (C) 1998 - 2017, 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 <errno.h> 24 #include "curl_setup.h" 25 26 #include "strtoofft.h" 27 28 /* 29 * NOTE: 30 * 31 * In the ISO C standard (IEEE Std 1003.1), there is a strtoimax() function we 32 * could use in case strtoll() doesn't exist... See 33 * https://www.opengroup.org/onlinepubs/009695399/functions/strtoimax.html 34 */ 35 36 #if (SIZEOF_CURL_OFF_T > SIZEOF_LONG) 37 # ifdef HAVE_STRTOLL 38 # define strtooff strtoll 39 # else 40 # if defined(_MSC_VER) && (_MSC_VER >= 1300) && (_INTEGRAL_MAX_BITS >= 64) 41 # if defined(_SAL_VERSION) 42 _Check_return_ _CRTIMP __int64 __cdecl _strtoi64( 43 _In_z_ const char *_String, 44 _Out_opt_ _Deref_post_z_ char **_EndPtr, _In_ int _Radix); 45 # else 46 _CRTIMP __int64 __cdecl _strtoi64(const char *_String, 47 char **_EndPtr, int _Radix); 48 # endif 49 # define strtooff _strtoi64 50 # else 51 # define PRIVATE_STRTOOFF 1 52 # endif 53 # endif 54 #else 55 # define strtooff strtol 56 #endif 57 58 #ifdef PRIVATE_STRTOOFF 59 60 /* Range tests can be used for alphanum decoding if characters are consecutive, 61 like in ASCII. Else an array is scanned. Determine this condition now. */ 62 63 #if('9' - '0') != 9 || ('Z' - 'A') != 25 || ('z' - 'a') != 25 64 65 #define NO_RANGE_TEST 66 67 static const char valchars[] = 68 "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"; 69 #endif 70 71 static int get_char(char c, int base); 72 73 /** 74 * Custom version of the strtooff function. This extracts a curl_off_t 75 * value from the given input string and returns it. 76 */ 77 static curl_off_t strtooff(const char *nptr, char **endptr, int base) 78 { 79 char *end; 80 int is_negative = 0; 81 int overflow; 82 int i; 83 curl_off_t value = 0; 84 curl_off_t newval; 85 86 /* Skip leading whitespace. */ 87 end = (char *)nptr; 88 while(ISSPACE(end[0])) { 89 end++; 90 } 91 92 /* Handle the sign, if any. */ 93 if(end[0] == '-') { 94 is_negative = 1; 95 end++; 96 } 97 else if(end[0] == '+') { 98 end++; 99 } 100 else if(end[0] == '\0') { 101 /* We had nothing but perhaps some whitespace -- there was no number. */ 102 if(endptr) { 103 *endptr = end; 104 } 105 return 0; 106 } 107 108 /* Handle special beginnings, if present and allowed. */ 109 if(end[0] == '0' && end[1] == 'x') { 110 if(base == 16 || base == 0) { 111 end += 2; 112 base = 16; 113 } 114 } 115 else if(end[0] == '0') { 116 if(base == 8 || base == 0) { 117 end++; 118 base = 8; 119 } 120 } 121 122 /* Matching strtol, if the base is 0 and it doesn't look like 123 * the number is octal or hex, we assume it's base 10. 124 */ 125 if(base == 0) { 126 base = 10; 127 } 128 129 /* Loop handling digits. */ 130 value = 0; 131 overflow = 0; 132 for(i = get_char(end[0], base); 133 i != -1; 134 end++, i = get_char(end[0], base)) { 135 newval = base * value + i; 136 if(newval < value) { 137 /* We've overflowed. */ 138 overflow = 1; 139 break; 140 } 141 else 142 value = newval; 143 } 144 145 if(!overflow) { 146 if(is_negative) { 147 /* Fix the sign. */ 148 value *= -1; 149 } 150 } 151 else { 152 if(is_negative) 153 value = CURL_OFF_T_MIN; 154 else 155 value = CURL_OFF_T_MAX; 156 157 errno = ERANGE; 158 } 159 160 if(endptr) 161 *endptr = end; 162 163 return value; 164 } 165 166 /** 167 * Returns the value of c in the given base, or -1 if c cannot 168 * be interpreted properly in that base (i.e., is out of range, 169 * is a null, etc.). 170 * 171 * @param c the character to interpret according to base 172 * @param base the base in which to interpret c 173 * 174 * @return the value of c in base, or -1 if c isn't in range 175 */ 176 static int get_char(char c, int base) 177 { 178 #ifndef NO_RANGE_TEST 179 int value = -1; 180 if(c <= '9' && c >= '0') { 181 value = c - '0'; 182 } 183 else if(c <= 'Z' && c >= 'A') { 184 value = c - 'A' + 10; 185 } 186 else if(c <= 'z' && c >= 'a') { 187 value = c - 'a' + 10; 188 } 189 #else 190 const char *cp; 191 int value; 192 193 cp = memchr(valchars, c, 10 + 26 + 26); 194 195 if(!cp) 196 return -1; 197 198 value = cp - valchars; 199 200 if(value >= 10 + 26) 201 value -= 26; /* Lowercase. */ 202 #endif 203 204 if(value >= base) { 205 value = -1; 206 } 207 208 return value; 209 } 210 #endif /* Only present if we need strtoll, but don't have it. */ 211 212 /* 213 * Parse a *positive* up to 64 bit number written in ascii. 214 */ 215 CURLofft curlx_strtoofft(const char *str, char **endp, int base, 216 curl_off_t *num) 217 { 218 char *end; 219 curl_off_t number; 220 errno = 0; 221 *num = 0; /* clear by default */ 222 223 DEBUGASSERT(str); 224 225 while(*str && ISSPACE(*str)) 226 str++; 227 if('-' == *str) { 228 if(endp) 229 *endp = (char *)str; /* didn't actually move */ 230 return CURL_OFFT_INVAL; /* nothing parsed */ 231 } 232 number = strtooff(str, &end, base); 233 if(endp) 234 *endp = end; 235 if(errno == ERANGE) 236 /* overflow/underflow */ 237 return CURL_OFFT_FLOW; 238 else if(str == end) 239 /* nothing parsed */ 240 return CURL_OFFT_INVAL; 241 242 *num = number; 243 return CURL_OFFT_OK; 244 } 245
