43 lines
703 B
C
43 lines
703 B
C
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/*++
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Copyright (c) 1988-1999 Microsoft Corporation
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Module Name:
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hstoi.c
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Abstract:
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Low level utility
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--*/
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#include "cmd.h"
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/*** hstoi - convert a hex string to an integer
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*
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* Conversion stops when the first non-hex character is found. If the first
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* character is not a hex character, 0 is returned.
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*
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* Eric K. Evans, Microsoft
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*/
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hstoi( TCHAR *s )
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{
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int result = 0 ;
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int digit ;
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if (s == NULL) {
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return 0;
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}
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s = SkipWhiteSpace( s );
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for ( ; *s && _istxdigit(*s) ; s++) {
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digit = (int) (*s <= TEXT('9')) ? (int)*s - (int)'0' : (int)_totlower(*s)-(int)'W' ;
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result = (result << 4)+digit ;
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} ;
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return (result) ;
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}
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