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 <span id="projectnumber">5.4.1</span>
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<div class="fragment"><pre class="fragment"><a name="l00001"></a>00001 <span class="comment">/*</span>
<a name="l00002"></a>00002 <span class="comment"> * Copyright (c) 1990 The Regents of the University of California.</span>
<a name="l00003"></a>00003 <span class="comment"> * All rights reserved.</span>
<a name="l00004"></a>00004 <span class="comment"> *</span>
<a name="l00005"></a>00005 <span class="comment"> * Redistribution and use in source and binary forms, with or without</span>
<a name="l00006"></a>00006 <span class="comment"> * modification, are permitted provided that the following conditions</span>
<a name="l00007"></a>00007 <span class="comment"> * are met:</span>
<a name="l00008"></a>00008 <span class="comment"> * 1. Redistributions of source code must retain the above copyright</span>
<a name="l00009"></a>00009 <span class="comment"> * notice, this list of conditions and the following disclaimer.</span>
<a name="l00010"></a>00010 <span class="comment"> * 2. Redistributions in binary form must reproduce the above copyright</span>
<a name="l00011"></a>00011 <span class="comment"> * notice, this list of conditions and the following disclaimer in the</span>
<a name="l00012"></a>00012 <span class="comment"> * documentation and/or other materials provided with the distribution.</span>
<a name="l00013"></a>00013 <span class="comment"> * 3. Neither the name of the University nor the names of its contributors</span>
<a name="l00014"></a>00014 <span class="comment"> * may be used to endorse or promote products derived from this software</span>
<a name="l00015"></a>00015 <span class="comment"> * without specific prior written permission.</span>
<a name="l00016"></a>00016 <span class="comment"> *</span>
<a name="l00017"></a>00017 <span class="comment"> * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND</span>
<a name="l00018"></a>00018 <span class="comment"> * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE</span>
<a name="l00019"></a>00019 <span class="comment"> * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE</span>
<a name="l00020"></a>00020 <span class="comment"> * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE</span>
<a name="l00021"></a>00021 <span class="comment"> * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL</span>
<a name="l00022"></a>00022 <span class="comment"> * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS</span>
<a name="l00023"></a>00023 <span class="comment"> * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)</span>
<a name="l00024"></a>00024 <span class="comment"> * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT</span>
<a name="l00025"></a>00025 <span class="comment"> * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY</span>
<a name="l00026"></a>00026 <span class="comment"> * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF</span>
<a name="l00027"></a>00027 <span class="comment"> * SUCH DAMAGE.</span>
<a name="l00028"></a>00028 <span class="comment"> */</span>
<a name="l00029"></a>00029
<a name="l00030"></a>00030 <span class="preprocessor">#include <net-snmp/net-snmp-config.h></span>
<a name="l00031"></a>00031
<a name="l00032"></a>00032 <span class="preprocessor">#if defined(LIBC_SCCS) && !defined(lint)</span>
<a name="l00033"></a>00033 <span class="preprocessor"></span><span class="keyword">static</span> <span class="keywordtype">char</span> sccsid[] = <span class="stringliteral">"@(#)strtol.c 5.4 (Berkeley) 2/23/91"</span>;
<a name="l00034"></a>00034 <span class="preprocessor">#endif </span><span class="comment">/* LIBC_SCCS and not lint */</span>
<a name="l00035"></a>00035
<a name="l00036"></a>00036 <span class="preprocessor">#if !HAVE_STRTOL</span>
<a name="l00037"></a>00037 <span class="preprocessor"></span>
<a name="l00038"></a>00038 <span class="preprocessor">#if HAVE_LIMITS_H</span>
<a name="l00039"></a>00039 <span class="preprocessor"></span><span class="preprocessor">#include <limits.h></span>
<a name="l00040"></a>00040 <span class="preprocessor">#endif</span>
<a name="l00041"></a>00041 <span class="preprocessor"></span><span class="preprocessor">#include <ctype.h></span>
<a name="l00042"></a>00042 <span class="preprocessor">#include <errno.h></span>
<a name="l00043"></a>00043 <span class="preprocessor">#if HAVE_STDLIB_H</span>
<a name="l00044"></a>00044 <span class="preprocessor"></span><span class="preprocessor">#include <stdlib.h></span>
<a name="l00045"></a>00045 <span class="preprocessor">#endif</span>
<a name="l00046"></a>00046 <span class="preprocessor"></span>
<a name="l00047"></a>00047 <span class="comment">/*</span>
<a name="l00048"></a>00048 <span class="comment"> * Convert a string to a long integer.</span>
<a name="l00049"></a>00049 <span class="comment"> *</span>
<a name="l00050"></a>00050 <span class="comment"> * Ignores `locale' stuff. Assumes that the upper and lower case</span>
<a name="l00051"></a>00051 <span class="comment"> * alphabets and digits are each contiguous.</span>
<a name="l00052"></a>00052 <span class="comment"> */</span>
<a name="l00053"></a>00053 <span class="keywordtype">long</span>
<a name="l00054"></a>00054 strtol(<span class="keyword">const</span> <span class="keywordtype">char</span> *nptr, <span class="keywordtype">char</span> **endptr, <span class="keywordtype">int</span> base)
<a name="l00055"></a>00055 {
<a name="l00056"></a>00056 <span class="keyword">const</span> <span class="keywordtype">char</span> *s = nptr;
<a name="l00057"></a>00057 <span class="keywordtype">unsigned</span> <span class="keywordtype">long</span> acc;
<a name="l00058"></a>00058 <span class="keywordtype">int</span> c;
<a name="l00059"></a>00059 <span class="keywordtype">unsigned</span> <span class="keywordtype">long</span> cutoff;
<a name="l00060"></a>00060 <span class="keywordtype">int</span> neg = 0, any, cutlim;
<a name="l00061"></a>00061
<a name="l00062"></a>00062 <span class="comment">/*</span>
<a name="l00063"></a>00063 <span class="comment"> * Skip white space and pick up leading +/- sign if any. If base is 0,</span>
<a name="l00064"></a>00064 <span class="comment"> * allow 0x for hex and 0 for octal, else assume decimal; if base is</span>
<a name="l00065"></a>00065 <span class="comment"> * already 16, allow 0x.</span>
<a name="l00066"></a>00066 <span class="comment"> */</span>
<a name="l00067"></a>00067 <span class="keywordflow">do</span> {
<a name="l00068"></a>00068 c = *s++;
<a name="l00069"></a>00069 } <span class="keywordflow">while</span> (isspace(c));
<a name="l00070"></a>00070 <span class="keywordflow">if</span> (c == <span class="charliteral">'-'</span>) {
<a name="l00071"></a>00071 neg = 1;
<a name="l00072"></a>00072 c = *s++;
<a name="l00073"></a>00073 } <span class="keywordflow">else</span> <span class="keywordflow">if</span> (c == <span class="charliteral">'+'</span>)
<a name="l00074"></a>00074 c = *s++;
<a name="l00075"></a>00075 <span class="keywordflow">if</span> ((base == 0 || base == 16) && c == <span class="charliteral">'0'</span> && (*s == <span class="charliteral">'x'</span> || *s == <span class="charliteral">'X'</span>)) {
<a name="l00076"></a>00076 c = s[1];
<a name="l00077"></a>00077 s += 2;
<a name="l00078"></a>00078 base = 16;
<a name="l00079"></a>00079 }
<a name="l00080"></a>00080 <span class="keywordflow">if</span> (base == 0)
<a name="l00081"></a>00081 base = c == <span class="charliteral">'0'</span> ? 8 : 10;
<a name="l00082"></a>00082
<a name="l00083"></a>00083 <span class="comment">/*</span>
<a name="l00084"></a>00084 <span class="comment"> * Compute the cutoff value between legal numbers and illegal numbers.</span>
<a name="l00085"></a>00085 <span class="comment"> * That is the largest legal value, divided by the base. An input</span>
<a name="l00086"></a>00086 <span class="comment"> * number that is greater than this value, if followed by a legal</span>
<a name="l00087"></a>00087 <span class="comment"> * input character, is too big. One that is equal to this value may</span>
<a name="l00088"></a>00088 <span class="comment"> * be valid or not; the limit between valid and invalid numbers is</span>
<a name="l00089"></a>00089 <span class="comment"> * then based on the last digit. For instance, if the range for longs</span>
<a name="l00090"></a>00090 <span class="comment"> * is [-2147483648..2147483647] and the input base is 10, cutoff will</span>
<a name="l00091"></a>00091 <span class="comment"> * be set to 214748364 and cutlim to either 7 (neg==0) or 8 (neg==1),</span>
<a name="l00092"></a>00092 <span class="comment"> * meaning that if we have accumulated a value > 214748364, or equal</span>
<a name="l00093"></a>00093 <span class="comment"> * but the next digit is > 7 (or 8), the number is too big, and we</span>
<a name="l00094"></a>00094 <span class="comment"> * will return a range error.</span>
<a name="l00095"></a>00095 <span class="comment"> *</span>
<a name="l00096"></a>00096 <span class="comment"> * Set any if any `digits' consumed; make it negative to indicate</span>
<a name="l00097"></a>00097 <span class="comment"> * overflow.</span>
<a name="l00098"></a>00098 <span class="comment"> */</span>
<a name="l00099"></a>00099 cutoff = neg ? -(<span class="keywordtype">unsigned</span> long) LONG_MIN : LONG_MAX;
<a name="l00100"></a>00100 cutlim = cutoff % (<span class="keywordtype">unsigned</span> long) base;
<a name="l00101"></a>00101 cutoff /= (<span class="keywordtype">unsigned</span> long) base;
<a name="l00102"></a>00102 <span class="keywordflow">for</span> (acc = 0, any = 0;; c = *s++) {
<a name="l00103"></a>00103 <span class="keywordflow">if</span> (isdigit(c))
<a name="l00104"></a>00104 c -= <span class="charliteral">'0'</span>;
<a name="l00105"></a>00105 <span class="keywordflow">else</span> <span class="keywordflow">if</span> (isalpha(c))
<a name="l00106"></a>00106 c -= isupper(c) ? <span class="charliteral">'A'</span> - 10 : <span class="charliteral">'a'</span> - 10;
<a name="l00107"></a>00107 <span class="keywordflow">else</span>
<a name="l00108"></a>00108 <span class="keywordflow">break</span>;
<a name="l00109"></a>00109 <span class="keywordflow">if</span> (c >= base)
<a name="l00110"></a>00110 <span class="keywordflow">break</span>;
<a name="l00111"></a>00111 <span class="keywordflow">if</span> (any < 0 || acc > cutoff || acc == cutoff && c > cutlim)
<a name="l00112"></a>00112 any = -1;
<a name="l00113"></a>00113 <span class="keywordflow">else</span> {
<a name="l00114"></a>00114 any = 1;
<a name="l00115"></a>00115 acc *= base;
<a name="l00116"></a>00116 acc += c;
<a name="l00117"></a>00117 }
<a name="l00118"></a>00118 }
<a name="l00119"></a>00119 <span class="keywordflow">if</span> (any < 0) {
<a name="l00120"></a>00120 acc = neg ? LONG_MIN : LONG_MAX;
<a name="l00121"></a>00121 errno = ERANGE;
<a name="l00122"></a>00122 } <span class="keywordflow">else</span> <span class="keywordflow">if</span> (neg)
<a name="l00123"></a>00123 acc = -acc;
<a name="l00124"></a>00124 <span class="keywordflow">if</span> (endptr != 0)
<a name="l00125"></a>00125 *endptr = any ? s - 1 : (<span class="keywordtype">char</span> *) nptr;
<a name="l00126"></a>00126 <span class="keywordflow">return</span> (acc);
<a name="l00127"></a>00127 }
<a name="l00128"></a>00128
<a name="l00129"></a>00129 <span class="preprocessor">#endif </span><span class="comment">/* !HAVE_STRTOL */</span>
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