|
| 1 | +/* |
| 2 | + * Copyright (c) 1990, 1993 |
| 3 | + *The Regents of the University of California. All rights reserved. |
| 4 | + * |
| 5 | + * Redistribution and use in source and binary forms, with or without |
| 6 | + * modification, are permitted provided that the following conditions |
| 7 | + * are met: |
| 8 | + * 1. Redistributions of source code must retain the above copyright |
| 9 | + * notice, this list of conditions and the following disclaimer. |
| 10 | + * 2. Redistributions in binary form must reproduce the above copyright |
| 11 | + * notice, this list of conditions and the following disclaimer in the |
| 12 | + * documentation and/or other materials provided with the distribution. |
| 13 | + * 3. All advertising materials mentioning features or use of this software |
| 14 | + * must display the following acknowledgement: |
| 15 | + *This product includes software developed by the University of |
| 16 | + *California, Berkeley and its contributors. |
| 17 | + * 4. Neither the name of the University nor the names of its contributors |
| 18 | + * may be used to endorse or promote products derived from this software |
| 19 | + * without specific prior written permission. |
| 20 | + * |
| 21 | + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| 22 | + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 23 | + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 24 | + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| 25 | + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 26 | + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 27 | + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 28 | + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 29 | + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 30 | + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 31 | + * SUCH DAMAGE. |
| 32 | + */ |
| 33 | + |
| 34 | +#if defined(LIBC_SCCS)&& !defined(lint) |
| 35 | +staticcharsccsid[]="@(#)strtoul.c8.1 (Berkeley) 6/4/93"; |
| 36 | +#endif/* LIBC_SCCS and not lint */ |
| 37 | + |
| 38 | +#include<limits.h> |
| 39 | +#include<ctype.h> |
| 40 | +#include<errno.h> |
| 41 | +#include<stdlib.h> |
| 42 | + |
| 43 | +/* |
| 44 | + * Convert a string to an unsigned long integer. |
| 45 | + * |
| 46 | + * Ignores `locale' stuff. Assumes that the upper and lower case |
| 47 | + * alphabets and digits are each contiguous. |
| 48 | + */ |
| 49 | +unsigned long |
| 50 | +strtoul(nptr,endptr,base) |
| 51 | +constchar*nptr; |
| 52 | +char**endptr; |
| 53 | +registerintbase; |
| 54 | +{ |
| 55 | +registerconstchar*s=nptr; |
| 56 | +registerunsigned longacc; |
| 57 | +registerunsignedcharc; |
| 58 | +registerunsigned longcutoff; |
| 59 | +registerintneg=0,any,cutlim; |
| 60 | + |
| 61 | +/* |
| 62 | + * See strtol for comments as to the logic used. |
| 63 | + */ |
| 64 | +do { |
| 65 | +c=*s++; |
| 66 | +}while (isspace(c)); |
| 67 | +if (c=='-') { |
| 68 | +neg=1; |
| 69 | +c=*s++; |
| 70 | +}elseif (c=='+') |
| 71 | +c=*s++; |
| 72 | +if ((base==0||base==16)&& |
| 73 | +c=='0'&& (*s=='x'||*s=='X')) { |
| 74 | +c=s[1]; |
| 75 | +s+=2; |
| 76 | +base=16; |
| 77 | +} |
| 78 | +if (base==0) |
| 79 | +base=c=='0' ?8 :10; |
| 80 | +cutoff= (unsigned long)ULONG_MAX / (unsigned long)base; |
| 81 | +cutlim= (unsigned long)ULONG_MAX % (unsigned long)base; |
| 82 | +for (acc=0,any=0;;c=*s++) { |
| 83 | +if (!isascii(c)) |
| 84 | +break; |
| 85 | +if (isdigit(c)) |
| 86 | +c-='0'; |
| 87 | +elseif (isalpha(c)) |
| 88 | +c-=isupper(c) ?'A'-10 :'a'-10; |
| 89 | +else |
| 90 | +break; |
| 91 | +if (c >=base) |
| 92 | +break; |
| 93 | +if (any<0||acc>cutoff|| (acc==cutoff&&c>cutlim)) |
| 94 | +any=-1; |
| 95 | +else { |
| 96 | +any=1; |
| 97 | +acc *=base; |
| 98 | +acc+=c; |
| 99 | +} |
| 100 | +} |
| 101 | +if (any<0) { |
| 102 | +acc=ULONG_MAX; |
| 103 | +errno=ERANGE; |
| 104 | +}elseif (neg) |
| 105 | +acc=-acc; |
| 106 | +if (endptr!=0) |
| 107 | +*endptr= (char*)(any ?s-1 :nptr); |
| 108 | +return (acc); |
| 109 | +} |