path: root/indra/llcommon/lluriparser.cpp

/** 
 * @file lluriparser.cpp
 * @author Protey
 * @date 2014-10-07
 * @brief Implementation of the LLUriParser class.
 *
 * $LicenseInfo:firstyear=2014&license=viewerlgpl$
 * Second Life Viewer Source Code
 * Copyright (C) 2014, Linden Research, Inc.
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation;
 * version 2.1 of the License only.
 * 
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 * 
 * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
 * $/LicenseInfo$
 */

#include "linden_common.h"
#include "lluriparser.h"

#if LL_DARWIN
#include <signal.h>
#include <setjmp.h>
#endif

LLUriParser::LLUriParser(const std::string& u) : mTmpScheme(false), mNormalizedTmp(false), mRes(0)
{
	if (u.find("://") == std::string::npos)
	{
		mNormalizedUri = "http://";
		mTmpScheme = true;
	}

	mNormalizedUri += u.c_str();

	mRes = parse();
}

LLUriParser::~LLUriParser()
{
	uriFreeUriMembersA(&mUri);
}

S32 LLUriParser::parse()
{
	mRes = uriParseSingleUriA(&mUri, mNormalizedUri.c_str(), NULL);
	return mRes;
}

const char * LLUriParser::scheme() const
{
	return mScheme.c_str();
}

void LLUriParser::sheme(const std::string& s)
{
	mTmpScheme = !s.size();
	mScheme = s;
}

const char * LLUriParser::port() const
{
	return mPort.c_str();
}

void LLUriParser::port(const std::string& s)
{
	mPort = s;
}

const char * LLUriParser::host() const
{
	return mHost.c_str();
}

void LLUriParser::host(const std::string& s)
{
	mHost = s;
}

const char * LLUriParser::path() const
{
	return mPath.c_str();
}

void LLUriParser::path(const std::string& s)
{
	mPath = s;
}

const char * LLUriParser::query() const
{
	return mQuery.c_str();
}

void LLUriParser::query(const std::string& s)
{
	mQuery = s;
}

const char * LLUriParser::fragment() const
{
	return mFragment.c_str();
}

void LLUriParser::fragment(const std::string& s)
{
	mFragment = s;
}

void LLUriParser::textRangeToString(UriTextRangeA& textRange, std::string& str)
{
	if (textRange.first != NULL && textRange.afterLast != NULL && textRange.first < textRange.afterLast)
	{
		const ptrdiff_t len = textRange.afterLast - textRange.first;
		str.assign(textRange.first, static_cast<std::string::size_type>(len));
	}
	else
	{
		str = LLStringUtil::null;
	}
}

void LLUriParser::extractParts()
{
	if (mTmpScheme || mNormalizedTmp)
	{
		mScheme.clear();
	}
	else
	{
		textRangeToString(mUri.scheme, mScheme);
	}
	
	textRangeToString(mUri.hostText, mHost);
	textRangeToString(mUri.portText, mPort);
	textRangeToString(mUri.query, mQuery);
	textRangeToString(mUri.fragment, mFragment);

	UriPathSegmentA * pathHead = mUri.pathHead;
	while (pathHead)
	{
		std::string partOfPath;
		textRangeToString(pathHead->text, partOfPath);

		mPath += '/';
		mPath += partOfPath;

		pathHead = pathHead->next;
	}
}

#if LL_DARWIN
typedef void(*sighandler_t)(int);
jmp_buf return_to_normalize;
static int sLastSignal = 0;
void uri_signal_handler(int signal)
{
    sLastSignal = signal;
    // Apparently signal handler throwing an exception doesn't work.
    // This is ugly and unsafe due to not unwinding content of uriparser library,
    // but unless we have a way to catch this as NSexception, jump appears to be the only option.
    longjmp(return_to_normalize, 1 /*setjmp will return this value*/);
}
#endif

S32 LLUriParser::normalize()
{
	mNormalizedTmp = mTmpScheme;
	if (!mRes)
	{
#if LL_DARWIN
        sighandler_t last_sigill_handler, last_sigbus_handler;
        last_sigill_handler = signal(SIGILL, &uri_signal_handler);		// illegal instruction
        last_sigbus_handler = signal(SIGBUS, &uri_signal_handler);
        
        if (setjmp(return_to_normalize))
        {
            // Issue: external library crashed via signal
            // If you encountered this, please try to figure out what's wrong:
            // 1. Verify that library's input is 'sane'
            // 2. Check if we have an NSexception to work with (unlikely)
            // 3. See if passing same string causes exception to repeat
            //
            // Crash happens at uriNormalizeSyntaxExA
            // Warning!!! This does not properly unwind stack,
            // if this can be handled by NSexception, it needs to be remade
            llassert(0);

            LL_WARNS() << "Uriparser crashed with " << sLastSignal << " , while processing: " << mNormalizedUri << LL_ENDL;
            signal(SIGILL, last_sigill_handler);
            signal(SIGBUS, last_sigbus_handler);
            return 1;
        }
#endif

        mRes = uriNormalizeSyntaxExA(&mUri, URI_NORMALIZE_SCHEME | URI_NORMALIZE_HOST);

#if LL_DARWIN
        signal(SIGILL, last_sigill_handler);
        signal(SIGBUS, last_sigbus_handler);
#endif

        if (!mRes)
        {
            S32 chars_required;
            mRes = uriToStringCharsRequiredA(&mUri, &chars_required);

            if (!mRes)
            {
                chars_required++;
                std::vector<char> label_buf(chars_required);
                mRes = uriToStringA(&label_buf[0], &mUri, chars_required, NULL);

                if (!mRes)
                {
                    mNormalizedUri = &label_buf[mTmpScheme ? 7 : 0];
                    mTmpScheme = false;
                }
            }
        }
	}

	if(mTmpScheme && mNormalizedUri.size() > 7)
	{
		mNormalizedUri = mNormalizedUri.substr(7);
		mTmpScheme = false;
	}

	return mRes;
}

void LLUriParser::glue(std::string& uri) const
{
	std::string first_part;
	glueFirst(first_part);

	std::string second_part;
	glueSecond(second_part);

	uri = first_part + second_part;
}

void LLUriParser::glueFirst(std::string& uri, bool use_scheme) const
{
	if (use_scheme && mScheme.size())
	{
		uri = mScheme;
		uri += "://";
	}
	else
	{
		uri.clear();
	}

	uri += mHost;
}

void LLUriParser::glueSecond(std::string& uri) const
{
	if (mPort.size())
	{
		uri = ':';
		uri += mPort;
	}
	else
	{
		uri.clear();
	}

	uri += mPath;

	if (mQuery.size())
	{
		uri += '?';
		uri += mQuery;
	}

	if (mFragment.size())
	{
		uri += '#';
		uri += mFragment;
	}
}

bool LLUriParser::test() const
{
	std::string uri;
	glue(uri);

	return uri == mNormalizedUri;
}

const char * LLUriParser::normalizedUri() const
{
	return mNormalizedUri.c_str();
}