strlen.c

Netscape NSPR库源码

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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 * License Version 1.1 (the "License"); you may not use this file
 * except in compliance with the License. You may obtain a copy of
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 * The Original Code is the Netscape Portable Runtime (NSPR).
 * 
 * The Initial Developer of the Original Code is Netscape
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 * Copyright (C) 1998-2000 Netscape Communications Corporation.  All
 * Rights Reserved.
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 * 
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 * terms of the GNU General Public License Version 2 or later (the
 * "GPL"), in which case the provisions of the GPL are applicable 
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#include "plstr.h"
#include "prtypes.h"
#include "prlog.h"

PR_IMPLEMENT(PRUint32)
PL_strlen(const char *str)
{
    register const char *s;

    if( (const char *)0 == str ) return 0;
    for( s = str; *s; s++ )
        ;
/* error checking in case we have a 64-bit platform -- make sure we dont
 * have ultra long strings that overflow a int32
 */ 
    if (sizeof(PRUint32) < sizeof(PRUptrdiff))
        PR_ASSERT((s-str) < 2147483647);

    return (PRUint32)(s - str);
}

PR_IMPLEMENT(PRUint32)
PL_strnlen(const char *str, PRUint32 max)
{
    register const char *s;

    if( (const char *)0 == str ) return 0;
    for( s = str; max && *s; s++, max-- )
        ;

    return (PRUint32)(s - str);
}