1/***************************************************************************
2 *                                  _   _ ____  _
3 *  Project                     ___| | | |  _ \| |
4 *                             / __| | | | |_) | |
5 *                            | (__| |_| |  _ <| |___
6 *                             \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) 1998 - 2011, Daniel Stenberg, <daniel@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 http://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
44static const char valchars[] =
45            "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
46#endif
47
48static 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 */
54curl_off_t
55curlx_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 */
154static 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