pjs/xpcom/base/nsID.cpp

141 строка
4.7 KiB
C++

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: NPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Netscape Public License
* Version 1.1 (the "License"); you may not use this file except in
* compliance with the License. You may obtain a copy of the License at
* http://www.mozilla.org/NPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is mozilla.org code.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Daniel Bratell <bratell@lysator.liu.se>
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the NPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the NPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#include "nsID.h"
#include "prprf.h"
#include "prmem.h"
static const char gIDFormat[] =
"{%08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x}";
static const char gIDFormat2[] =
"%08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x";
/**
* Multiplies the_int_var with 16 (0x10) and adds the value of the
* hexadecimal digit the_char. If it fails it returns PR_FALSE from
* the function it's used in.
*/
#define ADD_HEX_CHAR_TO_INT_OR_RETURN_FALSE(the_char, the_int_var) \
the_int_var = (the_int_var << 4) + the_char; \
if(the_char >= '0' && the_char <= '9') the_int_var -= '0'; \
else if(the_char >= 'a' && the_char <= 'f') the_int_var -= 'a'-10; \
else if(the_char >= 'A' && the_char <= 'F') the_int_var -= 'A'-10; \
else return PR_FALSE
/**
* Parses number_of_chars characters from the char_pointer pointer and
* puts the number in the dest_variable. The pointer is moved to point
* at the first character after the parsed ones. If it fails it returns
* PR_FALSE from the function the macro is used in.
*/
#define PARSE_CHARS_TO_NUM(char_pointer, dest_variable, number_of_chars) \
do { PRInt32 _i=number_of_chars; \
dest_variable = 0; \
while(_i) { \
ADD_HEX_CHAR_TO_INT_OR_RETURN_FALSE(*char_pointer, dest_variable); \
char_pointer++; \
_i--; \
} } while(0)
/**
* Parses a hyphen from the char_pointer string. If there is no hyphen there
* the function returns PR_FALSE from the function it's used in. The
* char_pointer is advanced one step.
*/
#define PARSE_HYPHEN(char_pointer) if(*(char_pointer++) != '-') return PR_FALSE
/*
* Turns a {xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx} string into
* an nsID. It can also handle the old format without the { and }.
*/
NS_COM PRBool nsID::Parse(const char *aIDStr)
{
/* Optimized for speed */
if(!aIDStr) {
return PR_FALSE;
}
PRBool expectFormat1 = (aIDStr[0] == '{');
if(expectFormat1) aIDStr++;
PARSE_CHARS_TO_NUM(aIDStr, m0, 8);
PARSE_HYPHEN(aIDStr);
PARSE_CHARS_TO_NUM(aIDStr, m1, 4);
PARSE_HYPHEN(aIDStr);
PARSE_CHARS_TO_NUM(aIDStr, m2, 4);
PARSE_HYPHEN(aIDStr);
int i;
for(i=0; i<2; i++)
PARSE_CHARS_TO_NUM(aIDStr, m3[i], 2);
PARSE_HYPHEN(aIDStr);
while(i < 8) {
PARSE_CHARS_TO_NUM(aIDStr, m3[i], 2);
i++;
}
return expectFormat1 ? *aIDStr == '}' : PR_TRUE;
}
/*
* Returns an allocated string in {xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}
* format. The string is allocated with PR_Malloc and should be freed by
* the caller.
*/
NS_COM char *nsID::ToString() const
{
char *res = (char*)PR_Malloc(39); // use PR_Malloc if this is to be freed with nsCRT::free
if (res != NULL) {
PR_snprintf(res, 39, gIDFormat,
m0, (PRUint32) m1, (PRUint32) m2,
(PRUint32) m3[0], (PRUint32) m3[1], (PRUint32) m3[2],
(PRUint32) m3[3], (PRUint32) m3[4], (PRUint32) m3[5],
(PRUint32) m3[6], (PRUint32) m3[7]);
}
return res;
}