netwerk/base/nsStandardURL.cpp
author Carsten "Tomcat" Book <cbook@mozilla.com>
Tue, 02 Jun 2015 13:05:56 +0200
changeset 279080 3c8ed81098ddbe4a4c09e7aa652b5288dc4ce0d3
parent 279055 7c3b45a47811b55f4e973d996dd149c5d575721b
child 279421 0abfbc98614806464c6d932627eabd699bb47cc4
permissions -rw-r--r--
Backed out 14 changesets (bug 1165515) for linux x64 e10s m2 test failures Backed out changeset d68dcf2ef372 (bug 1165515) Backed out changeset 7c3b45a47811 (bug 1165515) Backed out changeset b668b617bef2 (bug 1165515) Backed out changeset d0916e1283a2 (bug 1165515) Backed out changeset ac4dc7489942 (bug 1165515) Backed out changeset e9632ce8bc65 (bug 1165515) Backed out changeset c16d215cc7e4 (bug 1165515) Backed out changeset e4d474f3c51a (bug 1165515) Backed out changeset d87680bf9f7c (bug 1165515) Backed out changeset b3c0a45ba99e (bug 1165515) Backed out changeset 9370fa197674 (bug 1165515) Backed out changeset 50970d668ca1 (bug 1165515) Backed out changeset ffa4eb6d24b9 (bug 1165515) Backed out changeset 5fcf1203cc1d (bug 1165515)

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* vim:set ts=4 sw=4 sts=4 et cindent: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "IPCMessageUtils.h"

#include "nsStandardURL.h"
#include "nsCRT.h"
#include "nsEscape.h"
#include "nsIFile.h"
#include "nsIObjectInputStream.h"
#include "nsIObjectOutputStream.h"
#include "nsIPrefService.h"
#include "nsIPrefBranch.h"
#include "nsIIDNService.h"
#include "mozilla/Logging.h"
#include "nsAutoPtr.h"
#include "nsIURLParser.h"
#include "nsNetCID.h"
#include "mozilla/MemoryReporting.h"
#include "mozilla/ipc/URIUtils.h"
#include <algorithm>
#include "mozilla/dom/EncodingUtils.h"
#include "nsContentUtils.h"

using mozilla::dom::EncodingUtils;
using namespace mozilla::ipc;

static NS_DEFINE_CID(kThisImplCID, NS_THIS_STANDARDURL_IMPL_CID);
static NS_DEFINE_CID(kStandardURLCID, NS_STANDARDURL_CID);

nsIIDNService *nsStandardURL::gIDN = nullptr;
bool nsStandardURL::gInitialized = false;
bool nsStandardURL::gEscapeUTF8 = true;
bool nsStandardURL::gAlwaysEncodeInUTF8 = true;
char nsStandardURL::gHostLimitDigits[] = { '/', '\\', '?', '#', 0 };

//
// setenv NSPR_LOG_MODULES nsStandardURL:5
//
static PRLogModuleInfo *gStandardURLLog;

// The Chromium code defines its own LOG macro which we don't want
#undef LOG
#define LOG(args)     MOZ_LOG(gStandardURLLog, PR_LOG_DEBUG, args)
#undef LOG_ENABLED
#define LOG_ENABLED() PR_LOG_TEST(gStandardURLLog, PR_LOG_DEBUG)

//----------------------------------------------------------------------------

#define ENSURE_MUTABLE() \
  PR_BEGIN_MACRO \
    if (!mMutable) { \
        NS_WARNING("attempt to modify an immutable nsStandardURL"); \
        return NS_ERROR_ABORT; \
    } \
  PR_END_MACRO

//----------------------------------------------------------------------------

static nsresult
EncodeString(nsIUnicodeEncoder *encoder, const nsAFlatString &str, nsACString &result)
{
    nsresult rv;
    int32_t len = str.Length();
    int32_t maxlen;

    rv = encoder->GetMaxLength(str.get(), len, &maxlen);
    if (NS_FAILED(rv))
        return rv;

    char buf[256], *p = buf;
    if (uint32_t(maxlen) > sizeof(buf) - 1) {
        p = (char *) malloc(maxlen + 1);
        if (!p)
            return NS_ERROR_OUT_OF_MEMORY;
    }

    rv = encoder->Convert(str.get(), &len, p, &maxlen);
    if (NS_FAILED(rv))
        goto end;
    if (rv == NS_ERROR_UENC_NOMAPPING) {
        NS_WARNING("unicode conversion failed");
        rv = NS_ERROR_UNEXPECTED;
        goto end;
    }
    p[maxlen] = 0;
    result.Assign(p);

    len = sizeof(buf) - 1;
    rv = encoder->Finish(buf, &len);
    if (NS_FAILED(rv))
        goto end;
    buf[len] = 0;
    result.Append(buf);

end:
    encoder->Reset();

    if (p != buf)
        free(p);
    return rv;
}

//----------------------------------------------------------------------------
// nsStandardURL::nsPrefObserver
//----------------------------------------------------------------------------

#define NS_NET_PREF_ESCAPEUTF8         "network.standard-url.escape-utf8"
#define NS_NET_PREF_ALWAYSENCODEINUTF8 "network.standard-url.encode-utf8"

NS_IMPL_ISUPPORTS(nsStandardURL::nsPrefObserver, nsIObserver)

NS_IMETHODIMP nsStandardURL::
nsPrefObserver::Observe(nsISupports *subject,
                        const char *topic,
                        const char16_t *data)
{
    if (!strcmp(topic, NS_PREFBRANCH_PREFCHANGE_TOPIC_ID)) {
        nsCOMPtr<nsIPrefBranch> prefBranch( do_QueryInterface(subject) );
        if (prefBranch) {
            PrefsChanged(prefBranch, NS_ConvertUTF16toUTF8(data).get());
        } 
    }
    return NS_OK;
}

//----------------------------------------------------------------------------
// nsStandardURL::nsSegmentEncoder
//----------------------------------------------------------------------------

nsStandardURL::
nsSegmentEncoder::nsSegmentEncoder(const char *charset)
    : mCharset(charset)
{
}

int32_t nsStandardURL::
nsSegmentEncoder::EncodeSegmentCount(const char *str,
                                     const URLSegment &seg,
                                     int16_t mask,
                                     nsAFlatCString &result,
                                     bool &appended,
                                     uint32_t extraLen)
{
    // extraLen is characters outside the segment that will be 
    // added when the segment is not empty (like the @ following
    // a username).
    appended = false;
    if (!str)
        return 0;
    int32_t len = 0;
    if (seg.mLen > 0) {
        uint32_t pos = seg.mPos;
        len = seg.mLen;

        // first honor the origin charset if appropriate. as an optimization,
        // only do this if the segment is non-ASCII.  Further, if mCharset is
        // null or the empty string then the origin charset is UTF-8 and there
        // is nothing to do.
        nsAutoCString encBuf;
        if (mCharset && *mCharset && !nsCRT::IsAscii(str + pos, len)) {
            // we have to encode this segment
            if (mEncoder || InitUnicodeEncoder()) {
                NS_ConvertUTF8toUTF16 ucsBuf(Substring(str + pos, str + pos + len));
                if (NS_SUCCEEDED(EncodeString(mEncoder, ucsBuf, encBuf))) {
                    str = encBuf.get();
                    pos = 0;
                    len = encBuf.Length();
                }
                // else some failure occurred... assume UTF-8 is ok.
            }
        }

        // escape per RFC2396 unless UTF-8 and allowed by preferences
        int16_t escapeFlags = (gEscapeUTF8 || mEncoder) ? 0 : esc_OnlyASCII;

        uint32_t initLen = result.Length();

        // now perform any required escaping
        if (NS_EscapeURL(str + pos, len, mask | escapeFlags, result)) {
            len = result.Length() - initLen;
            appended = true;
        }
        else if (str == encBuf.get()) {
            result += encBuf; // append only!!
            len = encBuf.Length();
            appended = true;
        }
        len += extraLen;
    }
    return len;
}

const nsACString &nsStandardURL::
nsSegmentEncoder::EncodeSegment(const nsASingleFragmentCString &str,
                                int16_t mask,
                                nsAFlatCString &result)
{
    const char *text;
    bool encoded;
    EncodeSegmentCount(str.BeginReading(text), URLSegment(0, str.Length()), mask, result, encoded);
    if (encoded)
        return result;
    return str;
}

bool nsStandardURL::
nsSegmentEncoder::InitUnicodeEncoder()
{
    NS_ASSERTION(!mEncoder, "Don't call this if we have an encoder already!");
    // "replacement" won't survive another label resolution
    nsDependentCString label(mCharset);
    if (label.EqualsLiteral("replacement")) {
      mEncoder = EncodingUtils::EncoderForEncoding(label);
      return true;
    }
    nsAutoCString encoding;
    if (!EncodingUtils::FindEncodingForLabelNoReplacement(label, encoding)) {
      return false;
    }
    mEncoder = EncodingUtils::EncoderForEncoding(encoding);
    return true;
}

#define GET_SEGMENT_ENCODER_INTERNAL(name, useUTF8) \
    nsSegmentEncoder name(useUTF8 ? nullptr : mOriginCharset.get())

#define GET_SEGMENT_ENCODER(name) \
    GET_SEGMENT_ENCODER_INTERNAL(name, gAlwaysEncodeInUTF8)

#define GET_QUERY_ENCODER(name) \
    GET_SEGMENT_ENCODER_INTERNAL(name, false)

//----------------------------------------------------------------------------
// nsStandardURL <public>
//----------------------------------------------------------------------------

#ifdef DEBUG_DUMP_URLS_AT_SHUTDOWN
static PRCList gAllURLs;
#endif

nsStandardURL::nsStandardURL(bool aSupportsFileURL, bool aTrackURL)
    : mDefaultPort(-1)
    , mPort(-1)
    , mHostA(nullptr)
    , mHostEncoding(eEncoding_ASCII)
    , mSpecEncoding(eEncoding_Unknown)
    , mURLType(URLTYPE_STANDARD)
    , mMutable(true)
    , mSupportsFileURL(aSupportsFileURL)
{
    if (!gStandardURLLog)
        gStandardURLLog = PR_NewLogModule("nsStandardURL");

    LOG(("Creating nsStandardURL @%p\n", this));

    if (!gInitialized) {
        gInitialized = true;
        InitGlobalObjects();
    }

    // default parser in case nsIStandardURL::Init is never called
    mParser = net_GetStdURLParser();

#ifdef DEBUG_DUMP_URLS_AT_SHUTDOWN
    if (NS_IsMainThread()) {
        if (aTrackURL) {
            PR_APPEND_LINK(&mDebugCList, &gAllURLs);
        } else {
            PR_INIT_CLIST(&mDebugCList);
        }
    }
#endif
}

nsStandardURL::~nsStandardURL()
{
    LOG(("Destroying nsStandardURL @%p\n", this));

    if (mHostA) {
        free(mHostA);
    }
#ifdef DEBUG_DUMP_URLS_AT_SHUTDOWN
    if (NS_IsMainThread()) {
        if (!PR_CLIST_IS_EMPTY(&mDebugCList)) {
            PR_REMOVE_LINK(&mDebugCList);
        }
    }
#endif
}

#ifdef DEBUG_DUMP_URLS_AT_SHUTDOWN
struct DumpLeakedURLs {
    DumpLeakedURLs() {}
    ~DumpLeakedURLs();
};

DumpLeakedURLs::~DumpLeakedURLs()
{
    MOZ_ASSERT(NS_IsMainThread());
    if (!PR_CLIST_IS_EMPTY(&gAllURLs)) {
        printf("Leaked URLs:\n");
        for (PRCList *l = PR_LIST_HEAD(&gAllURLs); l != &gAllURLs; l = PR_NEXT_LINK(l)) {
            nsStandardURL *url = reinterpret_cast<nsStandardURL*>(reinterpret_cast<char*>(l) - offsetof(nsStandardURL, mDebugCList));
            url->PrintSpec();
        }
    }
}
#endif

void
nsStandardURL::InitGlobalObjects()
{
    nsCOMPtr<nsIPrefBranch> prefBranch( do_GetService(NS_PREFSERVICE_CONTRACTID) );
    if (prefBranch) {
        nsCOMPtr<nsIObserver> obs( new nsPrefObserver() );
        prefBranch->AddObserver(NS_NET_PREF_ESCAPEUTF8, obs.get(), false);
        prefBranch->AddObserver(NS_NET_PREF_ALWAYSENCODEINUTF8, obs.get(), false);

        PrefsChanged(prefBranch, nullptr);
    }

#ifdef DEBUG_DUMP_URLS_AT_SHUTDOWN
    PR_INIT_CLIST(&gAllURLs);
#endif
}

void
nsStandardURL::ShutdownGlobalObjects()
{
    NS_IF_RELEASE(gIDN);

#ifdef DEBUG_DUMP_URLS_AT_SHUTDOWN
    if (gInitialized) {
        // This instanciates a dummy class, and will trigger the class
        // destructor when libxul is unloaded. This is equivalent to atexit(),
        // but gracefully handles dlclose().
        static DumpLeakedURLs d;
    }
#endif
}

//----------------------------------------------------------------------------
// nsStandardURL <private>
//----------------------------------------------------------------------------

void
nsStandardURL::Clear()
{
    mSpec.Truncate();

    mPort = -1;

    mScheme.Reset();
    mAuthority.Reset();
    mUsername.Reset();
    mPassword.Reset();
    mHost.Reset();
    mHostEncoding = eEncoding_ASCII;

    mPath.Reset();
    mFilepath.Reset();
    mDirectory.Reset();
    mBasename.Reset();

    mExtension.Reset();
    mQuery.Reset();
    mRef.Reset();

    InvalidateCache();
}

void
nsStandardURL::InvalidateCache(bool invalidateCachedFile)
{
    if (invalidateCachedFile)
        mFile = 0;
    if (mHostA) {
        free(mHostA);
        mHostA = nullptr;
    }
    mSpecEncoding = eEncoding_Unknown;
}

bool
nsStandardURL::NormalizeIDN(const nsCSubstring &host, nsCString &result)
{
    // If host is ACE, then convert to UTF-8.  Else, if host is already UTF-8,
    // then make sure it is normalized per IDN.

    // this function returns true if normalization succeeds.

    // NOTE: As a side-effect this function sets mHostEncoding.  While it would
    // be nice to avoid side-effects in this function, the implementation of
    // this function is already somewhat bound to the behavior of the
    // callsites.  Anyways, this function exists to avoid code duplication, so
    // side-effects abound :-/

    NS_ASSERTION(mHostEncoding == eEncoding_ASCII, "unexpected default encoding");

    bool isASCII;
    if (!gIDN) {
        nsCOMPtr<nsIIDNService> serv(do_GetService(NS_IDNSERVICE_CONTRACTID));
        if (serv) {
            NS_ADDREF(gIDN = serv.get());
        }
    }

    if (gIDN &&
        NS_SUCCEEDED(gIDN->ConvertToDisplayIDN(host, &isASCII, result))) {
        if (!isASCII)
          mHostEncoding = eEncoding_UTF8;

        return true;
    }

    result.Truncate();
    return false;
}

bool
nsStandardURL::ValidIPv6orHostname(const char *host)
{
    if (!host || !*host) {
        // Should not be NULL or empty string
        return false;
    }

    int32_t length = strlen(host);

    bool openBracket = host[0] == '[';
    bool closeBracket = host[length - 1] == ']';

    if (openBracket && closeBracket) {
        return net_IsValidIPv6Addr(host + 1, length - 2);
    }

    if (openBracket || closeBracket) {
        // Fail if only one of the brackets is present
        return false;
    }

    if (PL_strchr(host, ':')) {
        // Hostnames should not contain a colon
        return false;
    }

    return true;
}

void
nsStandardURL::CoalescePath(netCoalesceFlags coalesceFlag, char *path)
{
    net_CoalesceDirs(coalesceFlag, path);
    int32_t newLen = strlen(path);
    if (newLen < mPath.mLen) {
        int32_t diff = newLen - mPath.mLen;
        mPath.mLen = newLen;
        mDirectory.mLen += diff;
        mFilepath.mLen += diff;
        ShiftFromBasename(diff);
    }
}

uint32_t
nsStandardURL::AppendSegmentToBuf(char *buf, uint32_t i, const char *str, URLSegment &seg, const nsCString *escapedStr, bool useEscaped)
{
    if (seg.mLen > 0) {
        if (useEscaped) {
            seg.mLen = escapedStr->Length();
            memcpy(buf + i, escapedStr->get(), seg.mLen);
        }
        else
            memcpy(buf + i, str + seg.mPos, seg.mLen);
        seg.mPos = i;
        i += seg.mLen;
    } else {
        seg.mPos = i;
    }
    return i;
}

uint32_t
nsStandardURL::AppendToBuf(char *buf, uint32_t i, const char *str, uint32_t len)
{
    memcpy(buf + i, str, len);
    return i + len;
}

// basic algorithm:
//  1- escape url segments (for improved GetSpec efficiency)
//  2- allocate spec buffer
//  3- write url segments
//  4- update url segment positions and lengths
nsresult
nsStandardURL::BuildNormalizedSpec(const char *spec)
{
    // Assumptions: all member URLSegments must be relative the |spec| argument
    // passed to this function.

    // buffers for holding escaped url segments (these will remain empty unless
    // escaping is required).
    nsAutoCString encUsername, encPassword, encHost, encDirectory,
      encBasename, encExtension, encQuery, encRef;
    bool useEncUsername, useEncPassword, useEncHost = false,
      useEncDirectory, useEncBasename, useEncExtension, useEncQuery, useEncRef;
    nsAutoCString portbuf;

    //
    // escape each URL segment, if necessary, and calculate approximate normalized
    // spec length.
    //
    // [scheme://][username[:password]@]host[:port]/path[?query_string][#ref]

    uint32_t approxLen = 0;

    // the scheme is already ASCII
    if (mScheme.mLen > 0)
        approxLen += mScheme.mLen + 3; // includes room for "://", which we insert always

    // encode URL segments; convert UTF-8 to origin charset and possibly escape.
    // results written to encXXX variables only if |spec| is not already in the
    // appropriate encoding.
    {
        GET_SEGMENT_ENCODER(encoder);
        GET_QUERY_ENCODER(queryEncoder);
        // Items using an extraLen of 1 don't add anything unless mLen > 0
        // Username@
        approxLen += encoder.EncodeSegmentCount(spec, mUsername,  esc_Username,      encUsername,  useEncUsername, 1);
        // :password - we insert the ':' even if there's no actual password if "user:@" was in the spec
        if (mPassword.mLen >= 0)
            approxLen += 1 + encoder.EncodeSegmentCount(spec, mPassword,  esc_Password,      encPassword,  useEncPassword);
        // mHost is handled differently below due to encoding differences
        MOZ_ASSERT(mPort >= -1, "Invalid negative mPort");
        if (mPort != -1 && mPort != mDefaultPort)
        {
            // :port
            portbuf.AppendInt(mPort);
            approxLen += portbuf.Length() + 1;
        }

        approxLen += 1; // reserve space for possible leading '/' - may not be needed
        // Should just use mPath?  These are pessimistic, and thus waste space
        approxLen += encoder.EncodeSegmentCount(spec, mDirectory, esc_Directory,     encDirectory, useEncDirectory, 1);
        approxLen += encoder.EncodeSegmentCount(spec, mBasename,  esc_FileBaseName,  encBasename,  useEncBasename);
        approxLen += encoder.EncodeSegmentCount(spec, mExtension, esc_FileExtension, encExtension, useEncExtension, 1);

        // These next ones *always* add their leading character even if length is 0
        // Handles items like "http://#"
        // ?query
        if (mQuery.mLen >= 0)
            approxLen += 1 + queryEncoder.EncodeSegmentCount(spec, mQuery, esc_Query,        encQuery,     useEncQuery);
        // #ref

        if (mRef.mLen >= 0) {
            if (nsContentUtils::EncodeDecodeURLHash()) {
                approxLen += 1 + encoder.EncodeSegmentCount(spec, mRef, esc_Ref,
                                                            encRef, useEncRef);
            } else {
                approxLen += 1 + mRef.mLen;
                useEncRef = false;
            }
        }
    }

    // do not escape the hostname, if IPv6 address literal, mHost will
    // already point to a [ ] delimited IPv6 address literal.
    // However, perform Unicode normalization on it, as IDN does.
    mHostEncoding = eEncoding_ASCII;
    // Note that we don't disallow URLs without a host - file:, etc
    if (mHost.mLen > 0) {
        const nsCSubstring& tempHost =
            Substring(spec + mHost.mPos, spec + mHost.mPos + mHost.mLen);
        if (tempHost.FindChar('\0') != kNotFound)
            return NS_ERROR_MALFORMED_URI;  // null embedded in hostname
        if (tempHost.FindChar(' ') != kNotFound)
            return NS_ERROR_MALFORMED_URI;  // don't allow spaces in the hostname
        if ((useEncHost = NormalizeIDN(tempHost, encHost)))
            approxLen += encHost.Length();
        else
            approxLen += mHost.mLen;
    }

    //
    // generate the normalized URL string
    //
    // approxLen should be correct or 1 high
    if (!mSpec.SetLength(approxLen+1, mozilla::fallible)) // buf needs a trailing '\0' below
        return NS_ERROR_OUT_OF_MEMORY;
    char *buf;
    mSpec.BeginWriting(buf);
    uint32_t i = 0;

    if (mScheme.mLen > 0) {
        i = AppendSegmentToBuf(buf, i, spec, mScheme);
        net_ToLowerCase(buf + mScheme.mPos, mScheme.mLen);
        i = AppendToBuf(buf, i, "://", 3);
    }

    // record authority starting position
    mAuthority.mPos = i;

    // append authority
    if (mUsername.mLen > 0) {
        i = AppendSegmentToBuf(buf, i, spec, mUsername, &encUsername, useEncUsername);
        if (mPassword.mLen >= 0) {
            buf[i++] = ':';
            i = AppendSegmentToBuf(buf, i, spec, mPassword, &encPassword, useEncPassword);
        }
        buf[i++] = '@';
    }
    if (mHost.mLen > 0) {
        i = AppendSegmentToBuf(buf, i, spec, mHost, &encHost, useEncHost);
        net_ToLowerCase(buf + mHost.mPos, mHost.mLen);
        MOZ_ASSERT(mPort >= -1, "Invalid negative mPort");
        if (mPort != -1 && mPort != mDefaultPort) {
            buf[i++] = ':';
            // Already formatted while building approxLen
            i = AppendToBuf(buf, i, portbuf.get(), portbuf.Length());
        }
    }

    // record authority length
    mAuthority.mLen = i - mAuthority.mPos;

    // path must always start with a "/"
    if (mPath.mLen <= 0) {
        LOG(("setting path=/"));
        mDirectory.mPos = mFilepath.mPos = mPath.mPos = i;
        mDirectory.mLen = mFilepath.mLen = mPath.mLen = 1;
        // basename must exist, even if empty (bug 113508)
        mBasename.mPos = i+1;
        mBasename.mLen = 0;
        buf[i++] = '/';
    }
    else {
        uint32_t leadingSlash = 0;
        if (spec[mPath.mPos] != '/') {
            LOG(("adding leading slash to path\n"));
            leadingSlash = 1;
            buf[i++] = '/';
            // basename must exist, even if empty (bugs 113508, 429347)
            if (mBasename.mLen == -1) {
                mBasename.mPos = i;
                mBasename.mLen = 0;
            }
        }

        // record corrected (file)path starting position
        mPath.mPos = mFilepath.mPos = i - leadingSlash;

        i = AppendSegmentToBuf(buf, i, spec, mDirectory, &encDirectory, useEncDirectory);

        // the directory must end with a '/'
        if (buf[i-1] != '/') {
            buf[i++] = '/';
            mDirectory.mLen++;
        }

        i = AppendSegmentToBuf(buf, i, spec, mBasename, &encBasename, useEncBasename);

        // make corrections to directory segment if leadingSlash
        if (leadingSlash) {
            mDirectory.mPos = mPath.mPos;
            if (mDirectory.mLen >= 0)
                mDirectory.mLen += leadingSlash;
            else
                mDirectory.mLen = 1;
        }

        if (mExtension.mLen >= 0) {
            buf[i++] = '.';
            i = AppendSegmentToBuf(buf, i, spec, mExtension, &encExtension, useEncExtension);
        }
        // calculate corrected filepath length
        mFilepath.mLen = i - mFilepath.mPos;

        if (mQuery.mLen >= 0) {
            buf[i++] = '?';
            i = AppendSegmentToBuf(buf, i, spec, mQuery, &encQuery, useEncQuery);
        }
        if (mRef.mLen >= 0) {
            buf[i++] = '#';
            i = AppendSegmentToBuf(buf, i, spec, mRef, &encRef, useEncRef);
        }
        // calculate corrected path length
        mPath.mLen = i - mPath.mPos;
    }

    buf[i] = '\0';

    if (mDirectory.mLen > 1) {
        netCoalesceFlags coalesceFlag = NET_COALESCE_NORMAL;
        if (SegmentIs(buf,mScheme,"ftp")) {
            coalesceFlag = (netCoalesceFlags) (coalesceFlag 
                                        | NET_COALESCE_ALLOW_RELATIVE_ROOT
                                        | NET_COALESCE_DOUBLE_SLASH_IS_ROOT);
        }
        CoalescePath(coalesceFlag, buf + mDirectory.mPos);
    }
    mSpec.SetLength(strlen(buf));
    NS_ASSERTION(mSpec.Length() <= approxLen, "We've overflowed the mSpec buffer!");
    return NS_OK;
}

bool
nsStandardURL::SegmentIs(const URLSegment &seg, const char *val, bool ignoreCase)
{
    // one or both may be null
    if (!val || mSpec.IsEmpty())
        return (!val && (mSpec.IsEmpty() || seg.mLen < 0));
    if (seg.mLen < 0)
        return false;
    // if the first |seg.mLen| chars of |val| match, then |val| must
    // also be null terminated at |seg.mLen|.
    if (ignoreCase)
        return !PL_strncasecmp(mSpec.get() + seg.mPos, val, seg.mLen)
            && (val[seg.mLen] == '\0');
    else
        return !strncmp(mSpec.get() + seg.mPos, val, seg.mLen)
            && (val[seg.mLen] == '\0');
}

bool
nsStandardURL::SegmentIs(const char* spec, const URLSegment &seg, const char *val, bool ignoreCase)
{
    // one or both may be null
    if (!val || !spec)
        return (!val && (!spec || seg.mLen < 0));
    if (seg.mLen < 0)
        return false;
    // if the first |seg.mLen| chars of |val| match, then |val| must
    // also be null terminated at |seg.mLen|.
    if (ignoreCase)
        return !PL_strncasecmp(spec + seg.mPos, val, seg.mLen)
            && (val[seg.mLen] == '\0');
    else
        return !strncmp(spec + seg.mPos, val, seg.mLen)
            && (val[seg.mLen] == '\0');
}

bool
nsStandardURL::SegmentIs(const URLSegment &seg1, const char *val, const URLSegment &seg2, bool ignoreCase)
{
    if (seg1.mLen != seg2.mLen)
        return false;
    if (seg1.mLen == -1 || (!val && mSpec.IsEmpty()))
        return true; // both are empty
    if (!val)
        return false;
    if (ignoreCase)
        return !PL_strncasecmp(mSpec.get() + seg1.mPos, val + seg2.mPos, seg1.mLen); 
    else
        return !strncmp(mSpec.get() + seg1.mPos, val + seg2.mPos, seg1.mLen); 
}

int32_t
nsStandardURL::ReplaceSegment(uint32_t pos, uint32_t len, const char *val, uint32_t valLen)
{
    if (val && valLen) {
        if (len == 0)
            mSpec.Insert(val, pos, valLen);
        else
            mSpec.Replace(pos, len, nsDependentCString(val, valLen));
        return valLen - len;
    }

    // else remove the specified segment
    mSpec.Cut(pos, len);
    return -int32_t(len);
}

int32_t
nsStandardURL::ReplaceSegment(uint32_t pos, uint32_t len, const nsACString &val)
{
    if (len == 0)
        mSpec.Insert(val, pos);
    else
        mSpec.Replace(pos, len, val);
    return val.Length() - len;
}

nsresult
nsStandardURL::ParseURL(const char *spec, int32_t specLen)
{
    nsresult rv;

    if (specLen > net_GetURLMaxLength()) {
        return NS_ERROR_MALFORMED_URI;
    }

    //
    // parse given URL string
    //
    rv = mParser->ParseURL(spec, specLen,
                           &mScheme.mPos, &mScheme.mLen,
                           &mAuthority.mPos, &mAuthority.mLen,
                           &mPath.mPos, &mPath.mLen);
    if (NS_FAILED(rv)) return rv;

#ifdef DEBUG
    if (mScheme.mLen <= 0) {
        printf("spec=%s\n", spec);
        NS_WARNING("malformed url: no scheme");
    }
#endif
     
    if (mAuthority.mLen > 0) {
        rv = mParser->ParseAuthority(spec + mAuthority.mPos, mAuthority.mLen,
                                     &mUsername.mPos, &mUsername.mLen,
                                     &mPassword.mPos, &mPassword.mLen,
                                     &mHost.mPos, &mHost.mLen,
                                     &mPort);
        if (NS_FAILED(rv)) return rv;

        // Don't allow mPort to be set to this URI's default port
        if (mPort == mDefaultPort)
            mPort = -1;

        mUsername.mPos += mAuthority.mPos;
        mPassword.mPos += mAuthority.mPos;
        mHost.mPos += mAuthority.mPos;
    }

    if (mPath.mLen > 0)
        rv = ParsePath(spec, mPath.mPos, mPath.mLen);

    return rv;
}

nsresult
nsStandardURL::ParsePath(const char *spec, uint32_t pathPos, int32_t pathLen)
{
    LOG(("ParsePath: %s pathpos %d len %d\n",spec,pathPos,pathLen));

    if (pathLen > net_GetURLMaxLength()) {
        return NS_ERROR_MALFORMED_URI;
    }

    nsresult rv = mParser->ParsePath(spec + pathPos, pathLen,
                                     &mFilepath.mPos, &mFilepath.mLen,
                                     &mQuery.mPos, &mQuery.mLen,
                                     &mRef.mPos, &mRef.mLen);
    if (NS_FAILED(rv)) return rv;

    mFilepath.mPos += pathPos;
    mQuery.mPos += pathPos;
    mRef.mPos += pathPos;

    if (mFilepath.mLen > 0) {
        rv = mParser->ParseFilePath(spec + mFilepath.mPos, mFilepath.mLen,
                                    &mDirectory.mPos, &mDirectory.mLen,
                                    &mBasename.mPos, &mBasename.mLen,
                                    &mExtension.mPos, &mExtension.mLen);
        if (NS_FAILED(rv)) return rv;

        mDirectory.mPos += mFilepath.mPos;
        mBasename.mPos += mFilepath.mPos;
        mExtension.mPos += mFilepath.mPos;
    }
    return NS_OK;
}

char *
nsStandardURL::AppendToSubstring(uint32_t pos,
                                 int32_t len,
                                 const char *tail)
{
    // Verify pos and length are within boundaries
    if (pos > mSpec.Length())
        return nullptr;
    if (len < 0)
        return nullptr;
    if ((uint32_t)len > (mSpec.Length() - pos))
        return nullptr;
    if (!tail)
        return nullptr;

    uint32_t tailLen = strlen(tail);

    // Check for int overflow for proposed length of combined string
    if (UINT32_MAX - ((uint32_t)len + 1) < tailLen)
        return nullptr;

    char *result = (char *) moz_xmalloc(len + tailLen + 1);
    if (result) {
        memcpy(result, mSpec.get() + pos, len);
        memcpy(result + len, tail, tailLen);
        result[len + tailLen] = '\0';
    }
    return result;
}

nsresult
nsStandardURL::ReadSegment(nsIBinaryInputStream *stream, URLSegment &seg)
{
    nsresult rv;

    rv = stream->Read32(&seg.mPos);
    if (NS_FAILED(rv)) return rv;

    rv = stream->Read32((uint32_t *) &seg.mLen);
    if (NS_FAILED(rv)) return rv;

    return NS_OK;
}

nsresult
nsStandardURL::WriteSegment(nsIBinaryOutputStream *stream, const URLSegment &seg)
{
    nsresult rv;

    rv = stream->Write32(seg.mPos);
    if (NS_FAILED(rv)) return rv;

    rv = stream->Write32(uint32_t(seg.mLen));
    if (NS_FAILED(rv)) return rv;

    return NS_OK;
}

/* static */ void
nsStandardURL::PrefsChanged(nsIPrefBranch *prefs, const char *pref)
{
    bool val;

    LOG(("nsStandardURL::PrefsChanged [pref=%s]\n", pref));

#define PREF_CHANGED(p) ((pref == nullptr) || !strcmp(pref, p))
#define GOT_PREF(p, b) (NS_SUCCEEDED(prefs->GetBoolPref(p, &b)))

    if (PREF_CHANGED(NS_NET_PREF_ESCAPEUTF8)) {
        if (GOT_PREF(NS_NET_PREF_ESCAPEUTF8, val))
            gEscapeUTF8 = val;
        LOG(("escape UTF-8 %s\n", gEscapeUTF8 ? "enabled" : "disabled"));
    }

    if (PREF_CHANGED(NS_NET_PREF_ALWAYSENCODEINUTF8)) {
        if (GOT_PREF(NS_NET_PREF_ALWAYSENCODEINUTF8, val))
            gAlwaysEncodeInUTF8 = val;
        LOG(("encode in UTF-8 %s\n", gAlwaysEncodeInUTF8 ? "enabled" : "disabled"));
    }
#undef PREF_CHANGED
#undef GOT_PREF
}

//----------------------------------------------------------------------------
// nsStandardURL::nsISupports
//----------------------------------------------------------------------------

NS_IMPL_ADDREF(nsStandardURL)
NS_IMPL_RELEASE(nsStandardURL)

NS_INTERFACE_MAP_BEGIN(nsStandardURL)
    NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIStandardURL)
    NS_INTERFACE_MAP_ENTRY(nsIURI)
    NS_INTERFACE_MAP_ENTRY(nsIURL)
    NS_INTERFACE_MAP_ENTRY_CONDITIONAL(nsIFileURL, mSupportsFileURL)
    NS_INTERFACE_MAP_ENTRY(nsIStandardURL)
    NS_INTERFACE_MAP_ENTRY(nsISerializable)
    NS_INTERFACE_MAP_ENTRY(nsIClassInfo)
    NS_INTERFACE_MAP_ENTRY(nsIMutable)
    NS_INTERFACE_MAP_ENTRY(nsIIPCSerializableURI)
    // see nsStandardURL::Equals
    if (aIID.Equals(kThisImplCID))
        foundInterface = static_cast<nsIURI *>(this);
    else
    NS_INTERFACE_MAP_ENTRY(nsISizeOf)
NS_INTERFACE_MAP_END

//----------------------------------------------------------------------------
// nsStandardURL::nsIURI
//----------------------------------------------------------------------------

// result may contain unescaped UTF-8 characters
NS_IMETHODIMP
nsStandardURL::GetSpec(nsACString &result)
{
    result = mSpec;
    return NS_OK;
}

// result may contain unescaped UTF-8 characters
NS_IMETHODIMP
nsStandardURL::GetSpecIgnoringRef(nsACString &result)
{
    // URI without ref is 0 to one char before ref
    if (mRef.mLen >= 0) {
        URLSegment noRef(0, mRef.mPos - 1);

        result = Segment(noRef);
    } else {
        result = mSpec;
    }
    return NS_OK;
}

// result may contain unescaped UTF-8 characters
NS_IMETHODIMP
nsStandardURL::GetPrePath(nsACString &result)
{
    result = Prepath();
    return NS_OK;
}

// result is strictly US-ASCII
NS_IMETHODIMP
nsStandardURL::GetScheme(nsACString &result)
{
    result = Scheme();
    return NS_OK;
}

// result may contain unescaped UTF-8 characters
NS_IMETHODIMP
nsStandardURL::GetUserPass(nsACString &result)
{
    result = Userpass();
    return NS_OK;
}

// result may contain unescaped UTF-8 characters
NS_IMETHODIMP
nsStandardURL::GetUsername(nsACString &result)
{
    result = Username();
    return NS_OK;
}

// result may contain unescaped UTF-8 characters
NS_IMETHODIMP
nsStandardURL::GetPassword(nsACString &result)
{
    result = Password();
    return NS_OK;
}

NS_IMETHODIMP
nsStandardURL::GetHostPort(nsACString &result)
{
    result = Hostport();
    return NS_OK;
}

NS_IMETHODIMP
nsStandardURL::GetHost(nsACString &result)
{
    result = Host();
    return NS_OK;
}

NS_IMETHODIMP
nsStandardURL::GetPort(int32_t *result)
{
    *result = mPort;
    return NS_OK;
}

// result may contain unescaped UTF-8 characters
NS_IMETHODIMP
nsStandardURL::GetPath(nsACString &result)
{
    result = Path();
    return NS_OK;
}

// result is ASCII
NS_IMETHODIMP
nsStandardURL::GetAsciiSpec(nsACString &result)
{
    if (mSpecEncoding == eEncoding_Unknown) {
        if (IsASCII(mSpec))
            mSpecEncoding = eEncoding_ASCII;
        else
            mSpecEncoding = eEncoding_UTF8;
    }

    if (mSpecEncoding == eEncoding_ASCII) {
        result = mSpec;
        return NS_OK;
    }

    // try to guess the capacity required for result...
    result.SetCapacity(mSpec.Length() + std::min<uint32_t>(32, mSpec.Length()/10));

    result = Substring(mSpec, 0, mScheme.mLen + 3);

    NS_EscapeURL(Userpass(true), esc_OnlyNonASCII | esc_AlwaysCopy, result);

    // get escaped host
    nsAutoCString escHostport;
    if (mHost.mLen > 0) {
        // this doesn't fail
        (void) GetAsciiHost(escHostport);

        // escHostport = "hostA" + ":port"
        uint32_t pos = mHost.mPos + mHost.mLen;
        if (pos < mPath.mPos)
            escHostport += Substring(mSpec, pos, mPath.mPos - pos);
    }
    result += escHostport;

    NS_EscapeURL(Path(), esc_OnlyNonASCII | esc_AlwaysCopy, result);
    return NS_OK;
}

// result is ASCII
NS_IMETHODIMP
nsStandardURL::GetAsciiHost(nsACString &result)
{
    if (mHostEncoding == eEncoding_ASCII) {
        result = Host();
        return NS_OK;
    }

    // perhaps we have it cached...
    if (mHostA) {
        result = mHostA;
        return NS_OK;
    }

    if (gIDN) {
        nsresult rv;
        rv = gIDN->ConvertUTF8toACE(Host(), result);
        if (NS_SUCCEEDED(rv)) {
            mHostA = ToNewCString(result);
            return NS_OK;
        }
        NS_WARNING("nsIDNService::ConvertUTF8toACE failed");
    }

    // something went wrong... guess all we can do is URL escape :-/
    NS_EscapeURL(Host(), esc_OnlyNonASCII | esc_AlwaysCopy, result);
    return NS_OK;
}

NS_IMETHODIMP
nsStandardURL::GetOriginCharset(nsACString &result)
{
    if (mOriginCharset.IsEmpty())
        result.AssignLiteral("UTF-8");
    else
        result = mOriginCharset;
    return NS_OK;
}

NS_IMETHODIMP
nsStandardURL::SetSpec(const nsACString &input)
{
    ENSURE_MUTABLE();

    const nsPromiseFlatCString &flat = PromiseFlatCString(input);
    const char *spec = flat.get();
    int32_t specLength = flat.Length();

    LOG(("nsStandardURL::SetSpec [spec=%s]\n", spec));

    if (!spec || !*spec)
        return NS_ERROR_MALFORMED_URI;

    if (input.Length() > (uint32_t) net_GetURLMaxLength()) {
        return NS_ERROR_MALFORMED_URI;
    }

    int32_t refPos = input.FindChar('#');
    if (refPos != kNotFound) {
        const nsCSubstring& sub = Substring(input, refPos, input.Length());
        nsresult rv = CheckRefCharacters(sub);
        if (NS_FAILED(rv)) {
            return rv;
        }
    }

    // Make a backup of the curent URL
    nsStandardURL prevURL(false,false);
    prevURL.CopyMembers(this, eHonorRef);
    Clear();

    // filter out unexpected chars "\r\n\t" if necessary
    nsAutoCString buf1;
    if (net_FilterURIString(spec, buf1)) {
        spec = buf1.get();
        specLength = buf1.Length();
    }

    // parse the given URL...
    nsresult rv = ParseURL(spec, specLength);
    if (NS_SUCCEEDED(rv)) {
        // finally, use the URLSegment member variables to build a normalized
        // copy of |spec|
        rv = BuildNormalizedSpec(spec);
    }

    if (NS_FAILED(rv)) {
        Clear();
        // If parsing the spec has failed, restore the old URL
        // so we don't end up with an empty URL.
        CopyMembers(&prevURL, eHonorRef);
        return rv;
    }

    if (LOG_ENABLED()) {
        LOG((" spec      = %s\n", mSpec.get()));
        LOG((" port      = %d\n", mPort));
        LOG((" scheme    = (%u,%d)\n", mScheme.mPos,    mScheme.mLen));
        LOG((" authority = (%u,%d)\n", mAuthority.mPos, mAuthority.mLen));
        LOG((" username  = (%u,%d)\n", mUsername.mPos,  mUsername.mLen));
        LOG((" password  = (%u,%d)\n", mPassword.mPos,  mPassword.mLen));
        LOG((" hostname  = (%u,%d)\n", mHost.mPos,      mHost.mLen));
        LOG((" path      = (%u,%d)\n", mPath.mPos,      mPath.mLen));
        LOG((" filepath  = (%u,%d)\n", mFilepath.mPos,  mFilepath.mLen));
        LOG((" directory = (%u,%d)\n", mDirectory.mPos, mDirectory.mLen));
        LOG((" basename  = (%u,%d)\n", mBasename.mPos,  mBasename.mLen));
        LOG((" extension = (%u,%d)\n", mExtension.mPos, mExtension.mLen));
        LOG((" query     = (%u,%d)\n", mQuery.mPos,     mQuery.mLen));
        LOG((" ref       = (%u,%d)\n", mRef.mPos,       mRef.mLen));
    }
    return rv;
}

NS_IMETHODIMP
nsStandardURL::SetScheme(const nsACString &input)
{
    ENSURE_MUTABLE();

    const nsPromiseFlatCString &scheme = PromiseFlatCString(input);

    LOG(("nsStandardURL::SetScheme [scheme=%s]\n", scheme.get()));

    if (scheme.IsEmpty()) {
        NS_WARNING("cannot remove the scheme from an url");
        return NS_ERROR_UNEXPECTED;
    }
    if (mScheme.mLen < 0) {
        NS_WARNING("uninitialized");
        return NS_ERROR_NOT_INITIALIZED;
    }

    if (!net_IsValidScheme(scheme)) {
        NS_WARNING("the given url scheme contains invalid characters");
        return NS_ERROR_UNEXPECTED;
    }

    InvalidateCache();

    int32_t shift = ReplaceSegment(mScheme.mPos, mScheme.mLen, scheme);

    if (shift) {
        mScheme.mLen = scheme.Length();
        ShiftFromAuthority(shift);
    }

    // ensure new scheme is lowercase
    //
    // XXX the string code unfortunately doesn't provide a ToLowerCase
    //     that operates on a substring.
    net_ToLowerCase((char *) mSpec.get(), mScheme.mLen);
    return NS_OK;
}

NS_IMETHODIMP
nsStandardURL::SetUserPass(const nsACString &input)
{
    ENSURE_MUTABLE();

    const nsPromiseFlatCString &userpass = PromiseFlatCString(input);

    LOG(("nsStandardURL::SetUserPass [userpass=%s]\n", userpass.get()));

    if (mURLType == URLTYPE_NO_AUTHORITY) {
        if (userpass.IsEmpty())
            return NS_OK;
        NS_WARNING("cannot set user:pass on no-auth url");
        return NS_ERROR_UNEXPECTED;
    }
    if (mAuthority.mLen < 0) {
        NS_WARNING("uninitialized");
        return NS_ERROR_NOT_INITIALIZED;
    }

    InvalidateCache();

    if (userpass.IsEmpty()) {
        // remove user:pass
        if (mUsername.mLen > 0) {
            if (mPassword.mLen > 0)
                mUsername.mLen += (mPassword.mLen + 1);
            mUsername.mLen++;
            mSpec.Cut(mUsername.mPos, mUsername.mLen);
            mAuthority.mLen -= mUsername.mLen;
            ShiftFromHost(-mUsername.mLen);
            mUsername.mLen = -1;
            mPassword.mLen = -1;
        }
        return NS_OK;
    }

    NS_ASSERTION(mHost.mLen >= 0, "uninitialized");

    nsresult rv;
    uint32_t usernamePos, passwordPos;
    int32_t usernameLen, passwordLen;

    rv = mParser->ParseUserInfo(userpass.get(), userpass.Length(),
                                &usernamePos, &usernameLen,
                                &passwordPos, &passwordLen);
    if (NS_FAILED(rv)) return rv;

    // build new user:pass in |buf|
    nsAutoCString buf;
    if (usernameLen > 0) {
        GET_SEGMENT_ENCODER(encoder);
        bool ignoredOut;
        usernameLen = encoder.EncodeSegmentCount(userpass.get(),
                                                 URLSegment(usernamePos,
                                                            usernameLen),
                                                 esc_Username | esc_AlwaysCopy,
                                                 buf, ignoredOut);
        if (passwordLen >= 0) {
            buf.Append(':');
            passwordLen = encoder.EncodeSegmentCount(userpass.get(),
                                                     URLSegment(passwordPos,
                                                                passwordLen),
                                                     esc_Password |
                                                     esc_AlwaysCopy, buf,
                                                     ignoredOut);
        }
        if (mUsername.mLen < 0)
            buf.Append('@');
    }

    uint32_t shift = 0;

    if (mUsername.mLen < 0) {
        // no existing user:pass
        if (!buf.IsEmpty()) {
            mSpec.Insert(buf, mHost.mPos);
            mUsername.mPos = mHost.mPos;
            shift = buf.Length();
        }
    }
    else {
        // replace existing user:pass
        uint32_t userpassLen = mUsername.mLen;
        if (mPassword.mLen >= 0)
            userpassLen += (mPassword.mLen + 1);
        mSpec.Replace(mUsername.mPos, userpassLen, buf);
        shift = buf.Length() - userpassLen;
    }
    if (shift) {
        ShiftFromHost(shift);
        mAuthority.mLen += shift;
    }
    // update positions and lengths
    mUsername.mLen = usernameLen;
    mPassword.mLen = passwordLen;
    if (passwordLen)
        mPassword.mPos = mUsername.mPos + mUsername.mLen + 1;
    return NS_OK;
}

NS_IMETHODIMP
nsStandardURL::SetUsername(const nsACString &input)
{
    ENSURE_MUTABLE();

    const nsPromiseFlatCString &username = PromiseFlatCString(input);

    LOG(("nsStandardURL::SetUsername [username=%s]\n", username.get()));

    if (mURLType == URLTYPE_NO_AUTHORITY) {
        if (username.IsEmpty())
            return NS_OK;
        NS_WARNING("cannot set username on no-auth url");
        return NS_ERROR_UNEXPECTED;
    }

    if (username.IsEmpty())
        return SetUserPass(username);

    InvalidateCache();

    // escape username if necessary
    nsAutoCString buf;
    GET_SEGMENT_ENCODER(encoder);
    const nsACString &escUsername =
        encoder.EncodeSegment(username, esc_Username, buf);

    int32_t shift;

    if (mUsername.mLen < 0) {
        mUsername.mPos = mAuthority.mPos;
        mSpec.Insert(escUsername + NS_LITERAL_CSTRING("@"), mUsername.mPos);
        shift = escUsername.Length() + 1;
    }
    else
        shift = ReplaceSegment(mUsername.mPos, mUsername.mLen, escUsername);

    if (shift) {
        mUsername.mLen = escUsername.Length();
        mAuthority.mLen += shift;
        ShiftFromPassword(shift);
    }
    return NS_OK;
}

NS_IMETHODIMP
nsStandardURL::SetPassword(const nsACString &input)
{
    ENSURE_MUTABLE();

    const nsPromiseFlatCString &password = PromiseFlatCString(input);

    LOG(("nsStandardURL::SetPassword [password=%s]\n", password.get()));

    if (mURLType == URLTYPE_NO_AUTHORITY) {
        if (password.IsEmpty())
            return NS_OK;
        NS_WARNING("cannot set password on no-auth url");
        return NS_ERROR_UNEXPECTED;
    }
    if (mUsername.mLen <= 0) {
        NS_WARNING("cannot set password without existing username");
        return NS_ERROR_FAILURE;
    }

    InvalidateCache();

    if (password.IsEmpty()) {
        if (mPassword.mLen >= 0) {
            // cut(":password")
            mSpec.Cut(mPassword.mPos - 1, mPassword.mLen + 1);
            ShiftFromHost(-(mPassword.mLen + 1));
            mAuthority.mLen -= (mPassword.mLen + 1);
            mPassword.mLen = -1;
        }
        return NS_OK;
    }

    // escape password if necessary
    nsAutoCString buf;
    GET_SEGMENT_ENCODER(encoder);
    const nsACString &escPassword =
        encoder.EncodeSegment(password, esc_Password, buf);

    int32_t shift;

    if (mPassword.mLen < 0) {
        mPassword.mPos = mUsername.mPos + mUsername.mLen + 1;
        mSpec.Insert(NS_LITERAL_CSTRING(":") + escPassword, mPassword.mPos - 1);
        shift = escPassword.Length() + 1;
    }
    else
        shift = ReplaceSegment(mPassword.mPos, mPassword.mLen, escPassword);

    if (shift) {
        mPassword.mLen = escPassword.Length();
        mAuthority.mLen += shift;
        ShiftFromHost(shift);
    }
    return NS_OK;
}

void
nsStandardURL::FindHostLimit(nsACString::const_iterator& aStart,
                             nsACString::const_iterator& aEnd)
{
  for (int32_t i = 0; gHostLimitDigits[i]; ++i) {
    nsACString::const_iterator c(aStart);
    if (FindCharInReadable(gHostLimitDigits[i], c, aEnd)) {
      aEnd = c;
    }
  }
}

NS_IMETHODIMP
nsStandardURL::SetHostPort(const nsACString &aValue)
{
    ENSURE_MUTABLE();

    // We cannot simply call nsIURI::SetHost because that would treat the name as
    // an IPv6 address (like http:://[server:443]/).  We also cannot call
    // nsIURI::SetHostPort because that isn't implemented.  Sadfaces.

    nsACString::const_iterator start, end;
    aValue.BeginReading(start);
    aValue.EndReading(end);
    nsACString::const_iterator iter(start);
    bool isIPv6 = false;

    FindHostLimit(start, end);

    if (*start == '[') { // IPv6 address
        if (!FindCharInReadable(']', iter, end)) {
            // the ] character is missing
            return NS_ERROR_MALFORMED_URI;
        }
        // iter now at the ']' character
        isIPv6 = true;
    } else {
        nsACString::const_iterator iter2(start);
        if (FindCharInReadable(']', iter2, end)) {
            // if the first char isn't [ then there should be no ] character
            return NS_ERROR_MALFORMED_URI;
        }
    }

    FindCharInReadable(':', iter, end);

    if (!isIPv6 && iter != end) {
        nsACString::const_iterator iter2(iter);
        iter2++; // Skip over the first ':' character
        if (FindCharInReadable(':', iter2, end)) {
            // If there is more than one ':' character it suggests an IPv6
            // The format should be [2001::1]:80 where the port is optional
            return NS_ERROR_MALFORMED_URI;
        }
    }

    nsresult rv = SetHost(Substring(start, iter));
    NS_ENSURE_SUCCESS(rv, rv);

    // Also set the port if needed.
    if (iter != end) {
        iter++;
        if (iter != end) {
            nsCString portStr(Substring(iter, end));
            nsresult rv;
            int32_t port = portStr.ToInteger(&rv);
            if (NS_SUCCEEDED(rv)) {
                rv = SetPort(port);
                NS_ENSURE_SUCCESS(rv, rv);
            } else {
                // Failure parsing port number
                return NS_ERROR_MALFORMED_URI;
            }
        } else {
            // port number is missing
            return NS_ERROR_MALFORMED_URI;
        }
    }

    return NS_OK;
}

NS_IMETHODIMP
nsStandardURL::SetHost(const nsACString &input)
{
    ENSURE_MUTABLE();

    const nsPromiseFlatCString &hostname = PromiseFlatCString(input);

    nsACString::const_iterator start, end;
    hostname.BeginReading(start);
    hostname.EndReading(end);

    FindHostLimit(start, end);

    const nsCString flat(Substring(start, end));
    const char *host = flat.get();

    LOG(("nsStandardURL::SetHost [host=%s]\n", host));

    if (mURLType == URLTYPE_NO_AUTHORITY) {
        if (flat.IsEmpty())
            return NS_OK;
        NS_WARNING("cannot set host on no-auth url");
        return NS_ERROR_UNEXPECTED;
    } else {
        if (flat.IsEmpty()) {
            // Setting an empty hostname is not allowed for
            // URLTYPE_STANDARD and URLTYPE_AUTHORITY.
            return NS_ERROR_UNEXPECTED;
        }
    }

    if (strlen(host) < flat.Length())
        return NS_ERROR_MALFORMED_URI; // found embedded null

    // For consistency with SetSpec/nsURLParsers, don't allow spaces
    // in the hostname.
    if (strchr(host, ' '))
        return NS_ERROR_MALFORMED_URI;

    if (!ValidIPv6orHostname(host)) {
        return NS_ERROR_MALFORMED_URI;
    }

    InvalidateCache();
    mHostEncoding = eEncoding_ASCII;

    int32_t len;
    nsAutoCString hostBuf;
    if (NormalizeIDN(flat, hostBuf)) {
        host = hostBuf.get();
        len = hostBuf.Length();
    }
    else
        len = flat.Length();

    if (mHost.mLen < 0) {
        int port_length = 0;
        if (mPort != -1) {
            nsAutoCString buf;
            buf.Assign(':');
            buf.AppendInt(mPort);
            port_length = buf.Length();
        }
        if (mAuthority.mLen > 0) {
            mHost.mPos = mAuthority.mPos + mAuthority.mLen - port_length;
            mHost.mLen = 0;
        } else if (mScheme.mLen > 0) {
            mHost.mPos = mScheme.mPos + mScheme.mLen + 3;
            mHost.mLen = 0;
        }
    }

    int32_t shift = ReplaceSegment(mHost.mPos, mHost.mLen, host, len);

    if (shift) {
        mHost.mLen = len;
        mAuthority.mLen += shift;
        ShiftFromPath(shift);
    }

    // Now canonicalize the host to lowercase
    net_ToLowerCase(mSpec.BeginWriting() + mHost.mPos, mHost.mLen);

    return NS_OK;
}
             
NS_IMETHODIMP
nsStandardURL::SetPort(int32_t port)
{
    ENSURE_MUTABLE();

    LOG(("nsStandardURL::SetPort [port=%d]\n", port));

    if ((port == mPort) || (mPort == -1 && port == mDefaultPort))
        return NS_OK;

    // ports must be >= 0
    if (port < -1) // -1 == use default
        return NS_ERROR_MALFORMED_URI;

    if (mURLType == URLTYPE_NO_AUTHORITY) {
        NS_WARNING("cannot set port on no-auth url");
        return NS_ERROR_UNEXPECTED;
    }

    InvalidateCache();

    if (mPort == -1) {
        // need to insert the port number in the URL spec
        nsAutoCString buf;
        buf.Assign(':');
        buf.AppendInt(port);
        mSpec.Insert(buf, mAuthority.mPos + mAuthority.mLen);
        mAuthority.mLen += buf.Length();
        ShiftFromPath(buf.Length());
    }
    else if (port == -1 || port == mDefaultPort) {
        // Don't allow mPort == mDefaultPort
        port = -1;

        // compute length of the current port
        nsAutoCString buf;
        buf.Assign(':');
        buf.AppendInt(mPort);

        // need to remove the port number from the URL spec
        uint32_t start = mAuthority.mPos + mAuthority.mLen - buf.Length();
        int32_t lengthToCut = buf.Length();
        mSpec.Cut(start, lengthToCut);
        mAuthority.mLen -= lengthToCut;
        ShiftFromPath(-lengthToCut);
    }
    else {
        // need to replace the existing port
        nsAutoCString buf;
        buf.Assign(':');
        buf.AppendInt(mPort);
        uint32_t start = mAuthority.mPos + mAuthority.mLen - buf.Length();
        uint32_t length = buf.Length();

        buf.Assign(':');
        buf.AppendInt(port);
        mSpec.Replace(start, length, buf);
        if (buf.Length() != length) {
            mAuthority.mLen += buf.Length() - length;
            ShiftFromPath(buf.Length() - length);
        }
    }

    mPort = port;
    return NS_OK;
}

NS_IMETHODIMP
nsStandardURL::SetPath(const nsACString &input)
{
    ENSURE_MUTABLE();

    const nsPromiseFlatCString &path = PromiseFlatCString(input);
    LOG(("nsStandardURL::SetPath [path=%s]\n", path.get()));

    InvalidateCache();

    if (!path.IsEmpty()) {
        nsAutoCString spec;

        spec.Assign(mSpec.get(), mPath.mPos);
        if (path.First() != '/')
            spec.Append('/');
        spec.Append(path);

        return SetSpec(spec);
    }
    else if (mPath.mLen >= 1) {
        mSpec.Cut(mPath.mPos + 1, mPath.mLen - 1);
        // these contain only a '/'
        mPath.mLen = 1;
        mDirectory.mLen = 1;
        mFilepath.mLen = 1;
        // these are no longer defined
        mBasename.mLen = -1;
        mExtension.mLen = -1;
        mQuery.mLen = -1;
        mRef.mLen = -1;
    }
    return NS_OK;
}

NS_IMETHODIMP
nsStandardURL::Equals(nsIURI *unknownOther, bool *result)
{
    return EqualsInternal(unknownOther, eHonorRef, result);
}

NS_IMETHODIMP
nsStandardURL::EqualsExceptRef(nsIURI *unknownOther, bool *result)
{
    return EqualsInternal(unknownOther, eIgnoreRef, result);
}

nsresult
nsStandardURL::EqualsInternal(nsIURI *unknownOther,
                              nsStandardURL::RefHandlingEnum refHandlingMode,
                              bool *result)
{
    NS_ENSURE_ARG_POINTER(unknownOther);
    NS_PRECONDITION(result, "null pointer");

    nsRefPtr<nsStandardURL> other;
    nsresult rv = unknownOther->QueryInterface(kThisImplCID,
                                               getter_AddRefs(other));
    if (NS_FAILED(rv)) {
        *result = false;
        return NS_OK;
    }

    // First, check whether one URIs is an nsIFileURL while the other
    // is not.  If that's the case, they're different.
    if (mSupportsFileURL != other->mSupportsFileURL) {
        *result = false;
        return NS_OK;
    }

    // Next check parts of a URI that, if different, automatically make the
    // URIs different
    if (!SegmentIs(mScheme, other->mSpec.get(), other->mScheme) ||
        // Check for host manually, since conversion to file will
        // ignore the host!
        !SegmentIs(mHost, other->mSpec.get(), other->mHost) ||
        !SegmentIs(mQuery, other->mSpec.get(), other->mQuery) ||
        !SegmentIs(mUsername, other->mSpec.get(), other->mUsername) ||
        !SegmentIs(mPassword, other->mSpec.get(), other->mPassword) ||
        Port() != other->Port()) {
        // No need to compare files or other URI parts -- these are different
        // beasties
        *result = false;
        return NS_OK;
    }

    if (refHandlingMode == eHonorRef &&
        !SegmentIs(mRef, other->mSpec.get(), other->mRef)) {
        *result = false;
        return NS_OK;
    }
    
    // Then check for exact identity of URIs.  If we have it, they're equal
    if (SegmentIs(mDirectory, other->mSpec.get(), other->mDirectory) &&
        SegmentIs(mBasename, other->mSpec.get(), other->mBasename) &&
        SegmentIs(mExtension, other->mSpec.get(), other->mExtension)) {
        *result = true;
        return NS_OK;
    }

    // At this point, the URIs are not identical, but they only differ in the
    // directory/filename/extension.  If these are file URLs, then get the
    // corresponding file objects and compare those, since two filenames that
    // differ, eg, only in case could still be equal.
    if (mSupportsFileURL) {
        // Assume not equal for failure cases... but failures in GetFile are
        // really failures, more or less, so propagate them to caller.
        *result = false;

        rv = EnsureFile();
        nsresult rv2 = other->EnsureFile();
        // special case for resource:// urls that don't resolve to files
        if (rv == NS_ERROR_NO_INTERFACE && rv == rv2) 
            return NS_OK;
        
        if (NS_FAILED(rv)) {
            LOG(("nsStandardURL::Equals [this=%p spec=%s] failed to ensure file",
                this, mSpec.get()));
            return rv;
        }
        NS_ASSERTION(mFile, "EnsureFile() lied!");
        rv = rv2;
        if (NS_FAILED(rv)) {
            LOG(("nsStandardURL::Equals [other=%p spec=%s] other failed to ensure file",
                 other.get(), other->mSpec.get()));
            return rv;
        }
        NS_ASSERTION(other->mFile, "EnsureFile() lied!");
        return mFile->Equals(other->mFile, result);
    }

    // The URLs are not identical, and they do not correspond to the
    // same file, so they are different.
    *result = false;

    return NS_OK;
}

NS_IMETHODIMP
nsStandardURL::SchemeIs(const char *scheme, bool *result)
{
    NS_PRECONDITION(result, "null pointer");

    *result = SegmentIs(mScheme, scheme);
    return NS_OK;
}

/* virtual */ nsStandardURL*
nsStandardURL::StartClone()
{
    nsStandardURL *clone = new nsStandardURL();
    return clone;
}

NS_IMETHODIMP
nsStandardURL::Clone(nsIURI **result)
{
    return CloneInternal(eHonorRef, result);
}


NS_IMETHODIMP
nsStandardURL::CloneIgnoringRef(nsIURI **result)
{
    return CloneInternal(eIgnoreRef, result);
}

nsresult
nsStandardURL::CloneInternal(nsStandardURL::RefHandlingEnum refHandlingMode,
                             nsIURI **result)

{
    nsRefPtr<nsStandardURL> clone = StartClone();
    if (!clone)
        return NS_ERROR_OUT_OF_MEMORY;

    // Copy local members into clone.
    // Also copies the cached members mFile, mHostA
    clone->CopyMembers(this, refHandlingMode, true);

    clone.forget(result);
    return NS_OK;
}

nsresult nsStandardURL::CopyMembers(nsStandardURL * source,
    nsStandardURL::RefHandlingEnum refHandlingMode, bool copyCached)
{
    mSpec = source->mSpec;
    mDefaultPort = source->mDefaultPort;
    mPort = source->mPort;
    mScheme = source->mScheme;
    mAuthority = source->mAuthority;
    mUsername = source->mUsername;
    mPassword = source->mPassword;
    mHost = source->mHost;
    mPath = source->mPath;
    mFilepath = source->mFilepath;
    mDirectory = source->mDirectory;
    mBasename = source->mBasename;
    mExtension = source->mExtension;
    mQuery = source->mQuery;
    mRef = source->mRef;
    mOriginCharset = source->mOriginCharset;
    mURLType = source->mURLType;
    mParser = source->mParser;
    mMutable = true;
    mSupportsFileURL = source->mSupportsFileURL;
    mHostEncoding = source->mHostEncoding;

    if (copyCached) {
        mFile = source->mFile;
        mHostA = source->mHostA ? strdup(source->mHostA) : nullptr;
        mSpecEncoding = source->mSpecEncoding;
    } else {
        // The same state as after calling InvalidateCache()
        mFile = nullptr;
        mHostA = nullptr;
        mSpecEncoding = eEncoding_Unknown;
    }

    if (refHandlingMode == eIgnoreRef) {
        SetRef(EmptyCString());
    }

    return NS_OK;
}

NS_IMETHODIMP
nsStandardURL::Resolve(const nsACString &in, nsACString &out)
{
    const nsPromiseFlatCString &flat = PromiseFlatCString(in);
    const char *relpath = flat.get();

    // filter out unexpected chars "\r\n\t" if necessary
    nsAutoCString buf;
    int32_t relpathLen;
    if (net_FilterURIString(relpath, buf)) {
        relpath = buf.get();
        relpathLen = buf.Length();
    } else
        relpathLen = flat.Length();
    
    char *result = nullptr;

    LOG(("nsStandardURL::Resolve [this=%p spec=%s relpath=%s]\n",
        this, mSpec.get(), relpath));

    NS_ASSERTION(mParser, "no parser: unitialized");

    // NOTE: there is no need for this function to produce normalized
    // output.  normalization will occur when the result is used to 
    // initialize a nsStandardURL object.

    if (mScheme.mLen < 0) {
        NS_WARNING("unable to Resolve URL: this URL not initialized");
        return NS_ERROR_NOT_INITIALIZED;
    }

    nsresult rv;
    URLSegment scheme;
    char *resultPath = nullptr;
    bool relative = false;
    uint32_t offset = 0;
    netCoalesceFlags coalesceFlag = NET_COALESCE_NORMAL;

    // relative urls should never contain a host, so we always want to use
    // the noauth url parser.
    // use it to extract a possible scheme
    rv = mParser->ParseURL(relpath, 
                           relpathLen,
                           &scheme.mPos, &scheme.mLen,
                           nullptr, nullptr,
                           nullptr, nullptr);

    // if the parser fails (for example because there is no valid scheme)
    // reset the scheme and assume a relative url
    if (NS_FAILED(rv)) scheme.Reset(); 

    if (scheme.mLen >= 0) {
        // add some flags to coalesceFlag if it is an ftp-url
        // need this later on when coalescing the resulting URL
        if (SegmentIs(relpath, scheme, "ftp", true)) {
            coalesceFlag = (netCoalesceFlags) (coalesceFlag 
                                        | NET_COALESCE_ALLOW_RELATIVE_ROOT
                                        | NET_COALESCE_DOUBLE_SLASH_IS_ROOT);

        }
        // this URL appears to be absolute
        // but try to find out more
        if (SegmentIs(mScheme, relpath, scheme, true)) {
            // mScheme and Scheme are the same 
            // but this can still be relative
            if (nsCRT::strncmp(relpath + scheme.mPos + scheme.mLen,
                               "://",3) == 0) {
                // now this is really absolute
                // because a :// follows the scheme 
                result = NS_strdup(relpath);
            } else {         
                // This is a deprecated form of relative urls like
                // http:file or http:/path/file
                // we will support it for now ...
                relative = true;
                offset = scheme.mLen + 1;
            }
        } else {
            // the schemes are not the same, we are also done
            // because we have to assume this is absolute 
            result = NS_strdup(relpath);
        }  
    } else {
        // add some flags to coalesceFlag if it is an ftp-url
        // need this later on when coalescing the resulting URL
        if (SegmentIs(mScheme,"ftp")) {
            coalesceFlag = (netCoalesceFlags) (coalesceFlag 
                                        | NET_COALESCE_ALLOW_RELATIVE_ROOT
                                        | NET_COALESCE_DOUBLE_SLASH_IS_ROOT);
        }
        if (relpath[0] == '/' && relpath[1] == '/') {
            // this URL //host/path is almost absolute
            result = AppendToSubstring(mScheme.mPos, mScheme.mLen + 1, relpath);
        } else {
            // then it must be relative 
            relative = true;
        }
    }
    if (relative) {
        uint32_t len = 0;
        const char *realrelpath = relpath + offset;
        switch (*realrelpath) {
        case '/':
            // overwrite everything after the authority
            len = mAuthority.mPos + mAuthority.mLen;
            break;
        case '?':
            // overwrite the existing ?query and #ref
            if (mQuery.mLen >= 0)
                len = mQuery.mPos - 1;
            else if (mRef.mLen >= 0)
                len = mRef.mPos - 1;
            else
                len = mPath.mPos + mPath.mLen;
            break;
        case '#':
        case '\0':
            // overwrite the existing #ref
            if (mRef.mLen < 0)
                len = mPath.mPos + mPath.mLen;
            else
                len = mRef.mPos - 1;
            break;
        default:
            if (coalesceFlag & NET_COALESCE_DOUBLE_SLASH_IS_ROOT) {
                if (Filename().Equals(NS_LITERAL_CSTRING("%2F"),
                                      nsCaseInsensitiveCStringComparator())) {
                    // if ftp URL ends with %2F then simply
                    // append relative part because %2F also
                    // marks the root directory with ftp-urls
                    len = mFilepath.mPos + mFilepath.mLen;
                } else {
                    // overwrite everything after the directory 
                    len = mDirectory.mPos + mDirectory.mLen;
                }
            } else { 
                // overwrite everything after the directory 
                len = mDirectory.mPos + mDirectory.mLen;
            }
        }
        result = AppendToSubstring(0, len, realrelpath);
        // locate result path
        resultPath = result + mPath.mPos;
    }
    if (!result)
        return NS_ERROR_OUT_OF_MEMORY;

    if (resultPath)
        net_CoalesceDirs(coalesceFlag, resultPath);
    else {
        // locate result path
        resultPath = PL_strstr(result, "://");
        if (resultPath) {
            resultPath = PL_strchr(resultPath + 3, '/');
            if (resultPath)
                net_CoalesceDirs(coalesceFlag,resultPath);
        }
    }
    out.Adopt(result);
    return NS_OK;
}

// result may contain unescaped UTF-8 characters
NS_IMETHODIMP
nsStandardURL::GetCommonBaseSpec(nsIURI *uri2, nsACString &aResult)
{
    NS_ENSURE_ARG_POINTER(uri2);

    // if uri's are equal, then return uri as is
    bool isEquals = false;
    if (NS_SUCCEEDED(Equals(uri2, &isEquals)) && isEquals)
        return GetSpec(aResult);

    aResult.Truncate();

    // check pre-path; if they don't match, then return empty string
    nsStandardURL *stdurl2;
    nsresult rv = uri2->QueryInterface(kThisImplCID, (void **) &stdurl2);
    isEquals = NS_SUCCEEDED(rv)
            && SegmentIs(mScheme, stdurl2->mSpec.get(), stdurl2->mScheme)    
            && SegmentIs(mHost, stdurl2->mSpec.get(), stdurl2->mHost)
            && SegmentIs(mUsername, stdurl2->mSpec.get(), stdurl2->mUsername)
            && SegmentIs(mPassword, stdurl2->mSpec.get(), stdurl2->mPassword)
            && (Port() == stdurl2->Port());
    if (!isEquals)
    {
        if (NS_SUCCEEDED(rv))
            NS_RELEASE(stdurl2);
        return NS_OK;
    }

    // scan for first mismatched character
    const char *thisIndex, *thatIndex, *startCharPos;
    startCharPos = mSpec.get() + mDirectory.mPos;
    thisIndex = startCharPos;
    thatIndex = stdurl2->mSpec.get() + mDirectory.mPos;
    while ((*thisIndex == *thatIndex) && *thisIndex)
    {
        thisIndex++;
        thatIndex++;
    }

    // backup to just after previous slash so we grab an appropriate path
    // segment such as a directory (not partial segments)
    // todo:  also check for file matches which include '?' and '#'
    while ((thisIndex != startCharPos) && (*(thisIndex-1) != '/'))
        thisIndex--;

    // grab spec from beginning to thisIndex
    aResult = Substring(mSpec, mScheme.mPos, thisIndex - mSpec.get());

    NS_RELEASE(stdurl2);
    return rv;
}

NS_IMETHODIMP
nsStandardURL::GetRelativeSpec(nsIURI *uri2, nsACString &aResult)
{
    NS_ENSURE_ARG_POINTER(uri2);

    aResult.Truncate();

    // if uri's are equal, then return empty string
    bool isEquals = false;
    if (NS_SUCCEEDED(Equals(uri2, &isEquals)) && isEquals)
        return NS_OK;

    nsStandardURL *stdurl2;
    nsresult rv = uri2->QueryInterface(kThisImplCID, (void **) &stdurl2);
    isEquals = NS_SUCCEEDED(rv)
            && SegmentIs(mScheme, stdurl2->mSpec.get(), stdurl2->mScheme)    
            && SegmentIs(mHost, stdurl2->mSpec.get(), stdurl2->mHost)
            && SegmentIs(mUsername, stdurl2->mSpec.get(), stdurl2->mUsername)
            && SegmentIs(mPassword, stdurl2->mSpec.get(), stdurl2->mPassword)
            && (Port() == stdurl2->Port());
    if (!isEquals)
    {
        if (NS_SUCCEEDED(rv))
            NS_RELEASE(stdurl2);

        return uri2->GetSpec(aResult);
    }

    // scan for first mismatched character
    const char *thisIndex, *thatIndex, *startCharPos;
    startCharPos = mSpec.get() + mDirectory.mPos;
    thisIndex = startCharPos;
    thatIndex = stdurl2->mSpec.get() + mDirectory.mPos;

#ifdef XP_WIN
    bool isFileScheme = SegmentIs(mScheme, "file");
    if (isFileScheme)
    {
        // on windows, we need to match the first segment of the path
        // if these don't match then we need to return an absolute path
        // skip over any leading '/' in path
        while ((*thisIndex == *thatIndex) && (*thisIndex == '/'))
        {
            thisIndex++;
            thatIndex++;
        }
        // look for end of first segment
        while ((*thisIndex == *thatIndex) && *thisIndex && (*thisIndex != '/'))
        {
            thisIndex++;
            thatIndex++;
        }

        // if we didn't match through the first segment, return absolute path
        if ((*thisIndex != '/') || (*thatIndex != '/'))
        {
            NS_RELEASE(stdurl2);
            return uri2->GetSpec(aResult);
        }
    }
#endif

    while ((*thisIndex == *thatIndex) && *thisIndex)
    {
        thisIndex++;
        thatIndex++;
    }

    // backup to just after previous slash so we grab an appropriate path
    // segment such as a directory (not partial segments)
    // todo:  also check for file matches with '#' and '?'
    while ((*(thatIndex-1) != '/') && (thatIndex != startCharPos))
        thatIndex--;

    const char *limit = mSpec.get() + mFilepath.mPos + mFilepath.mLen;

    // need to account for slashes and add corresponding "../"
    for (; thisIndex <= limit && *thisIndex; ++thisIndex)
    {
        if (*thisIndex == '/')
            aResult.AppendLiteral("../");
    }

    // grab spec from thisIndex to end
    uint32_t startPos = stdurl2->mScheme.mPos + thatIndex - stdurl2->mSpec.get();
    aResult.Append(Substring(stdurl2->mSpec, startPos, 
                             stdurl2->mSpec.Length() - startPos));

    NS_RELEASE(stdurl2);
    return rv;
}

//----------------------------------------------------------------------------
// nsStandardURL::nsIURL
//----------------------------------------------------------------------------

// result may contain unescaped UTF-8 characters
NS_IMETHODIMP
nsStandardURL::GetFilePath(nsACString &result)
{
    result = Filepath();
    return NS_OK;
}

// result may contain unescaped UTF-8 characters
NS_IMETHODIMP
nsStandardURL::GetQuery(nsACString &result)
{
    result = Query();
    return NS_OK;
}

// result may contain unescaped UTF-8 characters
NS_IMETHODIMP
nsStandardURL::GetRef(nsACString &result)
{
    result = Ref();
    return NS_OK;
}

NS_IMETHODIMP
nsStandardURL::GetHasRef(bool *result)
{
    *result = (mRef.mLen >= 0);
    return NS_OK;
}

// result may contain unescaped UTF-8 characters
NS_IMETHODIMP
nsStandardURL::GetDirectory(nsACString &result)
{
    result = Directory();
    return NS_OK;
}

// result may contain unescaped UTF-8 characters
NS_IMETHODIMP
nsStandardURL::GetFileName(nsACString &result)
{
    result = Filename();
    return NS_OK;
}

// result may contain unescaped UTF-8 characters
NS_IMETHODIMP
nsStandardURL::GetFileBaseName(nsACString &result)
{
    result = Basename();
    return NS_OK;
}

// result may contain unescaped UTF-8 characters
NS_IMETHODIMP
nsStandardURL::GetFileExtension(nsACString &result)
{
    result = Extension();
    return NS_OK;
}

NS_IMETHODIMP
nsStandardURL::SetFilePath(const nsACString &input)
{
    ENSURE_MUTABLE();

    const nsPromiseFlatCString &flat = PromiseFlatCString(input);
    const char *filepath = flat.get();

    LOG(("nsStandardURL::SetFilePath [filepath=%s]\n", filepath));

    // if there isn't a filepath, then there can't be anything
    // after the path either.  this url is likely uninitialized.
    if (mFilepath.mLen < 0)
        return SetPath(flat);

    if (filepath && *filepath) {
        nsAutoCString spec;
        uint32_t dirPos, basePos, extPos;
        int32_t dirLen, baseLen, extLen;
        nsresult rv;

        rv = mParser->ParseFilePath(filepath, -1,
                                    &dirPos, &dirLen,
                                    &basePos, &baseLen,
                                    &extPos, &extLen);
        if (NS_FAILED(rv)) return rv;

        // build up new candidate spec
        spec.Assign(mSpec.get(), mPath.mPos);

        // ensure leading '/'
        if (filepath[dirPos] != '/')
            spec.Append('/');

        GET_SEGMENT_ENCODER(encoder);

        // append encoded filepath components
        if (dirLen > 0)
            encoder.EncodeSegment(Substring(filepath + dirPos,
                                            filepath + dirPos + dirLen),
                                  esc_Directory | esc_AlwaysCopy, spec);
        if (baseLen > 0)
            encoder.EncodeSegment(Substring(filepath + basePos,
                                            filepath + basePos + baseLen),
                                  esc_FileBaseName | esc_AlwaysCopy, spec);
        if (extLen >= 0) {
            spec.Append('.');
            if (extLen > 0)
                encoder.EncodeSegment(Substring(filepath + extPos,
                                                filepath + extPos + extLen),
                                      esc_FileExtension | esc_AlwaysCopy,
                                      spec);
        }

        // compute the ending position of the current filepath
        if (mFilepath.mLen >= 0) {
            uint32_t end = mFilepath.mPos + mFilepath.mLen;
            if (mSpec.Length() > end)
                spec.Append(mSpec.get() + end, mSpec.Length() - end);
        }

        return SetSpec(spec);
    }
    else if (mPath.mLen > 1) {
        mSpec.Cut(mPath.mPos + 1, mFilepath.mLen - 1);
        // left shift query, and ref
        ShiftFromQuery(1 - mFilepath.mLen);
        // these contain only a '/'
        mPath.mLen = 1;
        mDirectory.mLen = 1;
        mFilepath.mLen = 1;
        // these are no longer defined
        mBasename.mLen = -1;
        mExtension.mLen = -1;
    }
    return NS_OK;
}

NS_IMETHODIMP
nsStandardURL::SetQuery(const nsACString &input)
{
    ENSURE_MUTABLE();

    const nsPromiseFlatCString &flat = PromiseFlatCString(input);
    const char *query = flat.get();

    LOG(("nsStandardURL::SetQuery [query=%s]\n", query));

    if (mPath.mLen < 0)
        return SetPath(flat);

    InvalidateCache();

    if (!query || !*query) {
        // remove existing query
        if (mQuery.mLen >= 0) {
            // remove query and leading '?'
            mSpec.Cut(mQuery.mPos - 1, mQuery.mLen + 1);
            ShiftFromRef(-(mQuery.mLen + 1));
            mPath.mLen -= (mQuery.mLen + 1);
            mQuery.mPos = 0;
            mQuery.mLen = -1;
        }
        return NS_OK;
    }

    int32_t queryLen = strlen(query);
    if (query[0] == '?') {
        query++;
        queryLen--;
    }

    if (mQuery.mLen < 0) {
        if (mRef.mLen < 0)
            mQuery.mPos = mSpec.Length();
        else
            mQuery.mPos = mRef.mPos - 1;
        mSpec.Insert('?', mQuery.mPos);
        mQuery.mPos++;
        mQuery.mLen = 0;
        // the insertion pushes these out by 1
        mPath.mLen++;
        mRef.mPos++;
    }

    // encode query if necessary
    nsAutoCString buf;
    bool encoded;
    GET_QUERY_ENCODER(encoder);
    encoder.EncodeSegmentCount(query, URLSegment(0, queryLen), esc_Query,
                               buf, encoded);
    if (encoded) {
        query = buf.get();
        queryLen = buf.Length();
    }

    int32_t shift = ReplaceSegment(mQuery.mPos, mQuery.mLen, query, queryLen);

    if (shift) {
        mQuery.mLen = queryLen;
        mPath.mLen += shift;
        ShiftFromRef(shift);
    }
    return NS_OK;
}

nsresult
nsStandardURL::CheckRefCharacters(const nsACString &input)
{
    nsACString::const_iterator start, end;
    input.BeginReading(start);
    input.EndReading(end);
    for (; start != end; ++start) {
        switch (*start) {
            case 0x00:
            case 0x09:
            case 0x0A:
            case 0x0D:
                // These characters are not allowed in the Ref part.
                return NS_ERROR_MALFORMED_URI;
            default:
                continue;
        }
    }
    return NS_OK;
}

NS_IMETHODIMP
nsStandardURL::SetRef(const nsACString &input)
{
    ENSURE_MUTABLE();

    const nsPromiseFlatCString &flat = PromiseFlatCString(input);
    const char *ref = flat.get();

    LOG(("nsStandardURL::SetRef [ref=%s]\n", ref));

    nsresult rv = CheckRefCharacters(input);
    if (NS_FAILED(rv)) {
        return rv;
    }

    if (mPath.mLen < 0)
        return SetPath(flat);

    InvalidateCache();

    if (!ref || !*ref) {
        // remove existing ref
        if (mRef.mLen >= 0) {
            // remove ref and leading '#'
            mSpec.Cut(mRef.mPos - 1, mRef.mLen + 1);
            mPath.mLen -= (mRef.mLen + 1);
            mRef.mPos = 0;
            mRef.mLen = -1;
        }
        return NS_OK;
    }

    int32_t refLen = flat.Length();
    if (ref[0] == '#') {
        ref++;
        refLen--;
    }
    
    if (mRef.mLen < 0) {
        mSpec.Append('#');
        ++mPath.mLen;  // Include the # in the path.
        mRef.mPos = mSpec.Length();
        mRef.mLen = 0;
    }

    // If precent encoding is necessary, `ref` will point to `buf`'s content.
    // `buf` needs to outlive any use of the `ref` pointer.
    nsAutoCString buf;
    if (nsContentUtils::EncodeDecodeURLHash()) {
        // encode ref if necessary
        bool encoded;
        GET_SEGMENT_ENCODER(encoder);
        encoder.EncodeSegmentCount(ref, URLSegment(0, refLen), esc_Ref,
                                   buf, encoded);
        if (encoded) {
            ref = buf.get();
            refLen = buf.Length();
        }
    }

    int32_t shift = ReplaceSegment(mRef.mPos, mRef.mLen, ref, refLen);
    mPath.mLen += shift;
    mRef.mLen = refLen;
    return NS_OK;
}

NS_IMETHODIMP
nsStandardURL::SetDirectory(const nsACString &input)
{
    NS_NOTYETIMPLEMENTED("");
    return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP
nsStandardURL::SetFileName(const nsACString &input)
{
    ENSURE_MUTABLE();

    const nsPromiseFlatCString &flat = PromiseFlatCString(input);
    const char *filename = flat.get();

    LOG(("nsStandardURL::SetFileName [filename=%s]\n", filename));

    if (mPath.mLen < 0)
        return SetPath(flat);

    int32_t shift = 0;

    if (!(filename && *filename)) {
        // remove the filename
        if (mBasename.mLen > 0) {
            if (mExtension.mLen >= 0)
                mBasename.mLen += (mExtension.mLen + 1);
            mSpec.Cut(mBasename.mPos, mBasename.mLen);
            shift = -mBasename.mLen;
            mBasename.mLen = 0;
            mExtension.mLen = -1;
        }
    }
    else {
        nsresult rv;
        URLSegment basename, extension;

        // let the parser locate the basename and extension
        rv = mParser->ParseFileName(filename, -1,
                                    &basename.mPos, &basename.mLen,
                                    &extension.mPos, &extension.mLen);
        if (NS_FAILED(rv)) return rv;

        if (basename.mLen < 0) {
            // remove existing filename
            if (mBasename.mLen >= 0) {
                uint32_t len = mBasename.mLen;
                if (mExtension.mLen >= 0)
                    len += (mExtension.mLen + 1);
                mSpec.Cut(mBasename.mPos, len);
                shift = -int32_t(len);
                mBasename.mLen = 0;
                mExtension.mLen = -1;
            }
        }
        else {
            nsAutoCString newFilename;
            bool ignoredOut;
            GET_SEGMENT_ENCODER(encoder);
            basename.mLen = encoder.EncodeSegmentCount(filename, basename,
                                                       esc_FileBaseName |
                                                       esc_AlwaysCopy,
                                                       newFilename,
                                                       ignoredOut);
            if (extension.mLen >= 0) {
                newFilename.Append('.');
                extension.mLen = encoder.EncodeSegmentCount(filename, extension,
                                                            esc_FileExtension |
                                                            esc_AlwaysCopy,
                                                            newFilename,
                                                            ignoredOut);
            }

            if (mBasename.mLen < 0) {
                // insert new filename
                mBasename.mPos = mDirectory.mPos + mDirectory.mLen;
                mSpec.Insert(newFilename, mBasename.mPos);
                shift = newFilename.Length();
            }
            else {
                // replace existing filename
                uint32_t oldLen = uint32_t(mBasename.mLen);
                if (mExtension.mLen >= 0)
                    oldLen += (mExtension.mLen + 1);
                mSpec.Replace(mBasename.mPos, oldLen, newFilename);
                shift = newFilename.Length() - oldLen;
            }
            
            mBasename.mLen = basename.mLen;
            mExtension.mLen = extension.mLen;
            if (mExtension.mLen >= 0)
                mExtension.mPos = mBasename.mPos + mBasename.mLen + 1;
        }
    }
    if (shift) {
        ShiftFromQuery(shift);
        mFilepath.mLen += shift;
        mPath.mLen += shift;
    }
    return NS_OK;
}

NS_IMETHODIMP
nsStandardURL::SetFileBaseName(const nsACString &input)
{
    nsAutoCString extension;
    nsresult rv = GetFileExtension(extension);
    NS_ENSURE_SUCCESS(rv, rv);

    nsAutoCString newFileName(input);

    if (!extension.IsEmpty()) {
        newFileName.Append('.');
        newFileName.Append(extension);
    }

    return SetFileName(newFileName);
}

NS_IMETHODIMP
nsStandardURL::SetFileExtension(const nsACString &input)
{
    nsAutoCString newFileName;
    nsresult rv = GetFileBaseName(newFileName);
    NS_ENSURE_SUCCESS(rv, rv);

    if (!input.IsEmpty()) {
        newFileName.Append('.');
        newFileName.Append(input);
    }

    return SetFileName(newFileName);
}

//----------------------------------------------------------------------------
// nsStandardURL::nsIFileURL
//----------------------------------------------------------------------------

nsresult
nsStandardURL::EnsureFile()
{
    NS_PRECONDITION(mSupportsFileURL,
                    "EnsureFile() called on a URL that doesn't support files!");
    if (mFile) {
        // Nothing to do
        return NS_OK;
    }

    // Parse the spec if we don't have a cached result
    if (mSpec.IsEmpty()) {
        NS_WARNING("url not initialized");
        return NS_ERROR_NOT_INITIALIZED;
    }

    if (!SegmentIs(mScheme, "file")) {
        NS_WARNING("not a file URL");
        return NS_ERROR_FAILURE;
    }

    return net_GetFileFromURLSpec(mSpec, getter_AddRefs(mFile));
}

NS_IMETHODIMP
nsStandardURL::GetFile(nsIFile **result)
{
    NS_PRECONDITION(mSupportsFileURL,
                    "GetFile() called on a URL that doesn't support files!");
    nsresult rv = EnsureFile();
    if (NS_FAILED(rv))
        return rv;

    if (LOG_ENABLED()) {
        nsAutoCString path;
        mFile->GetNativePath(path);
        LOG(("nsStandardURL::GetFile [this=%p spec=%s resulting_path=%s]\n",
            this, mSpec.get(), path.get()));
    }

    // clone the file, so the caller can modify it.
    // XXX nsIFileURL.idl specifies that the consumer must _not_ modify the
    // nsIFile returned from this method; but it seems that some folks do
    // (see bug 161921). until we can be sure that all the consumers are
    // behaving themselves, we'll stay on the safe side and clone the file.
    // see bug 212724 about fixing the consumers.
    return mFile->Clone(result);
}

NS_IMETHODIMP
nsStandardURL::SetFile(nsIFile *file)
{
    ENSURE_MUTABLE();

    NS_ENSURE_ARG_POINTER(file);

    nsresult rv;
    nsAutoCString url;

    rv = net_GetURLSpecFromFile(file, url);
    if (NS_FAILED(rv)) return rv;

    SetSpec(url);

    rv = Init(mURLType, mDefaultPort, url, nullptr, nullptr);

    // must clone |file| since its value is not guaranteed to remain constant
    if (NS_SUCCEEDED(rv)) {
        InvalidateCache();
        if (NS_FAILED(file->Clone(getter_AddRefs(mFile)))) {
            NS_WARNING("nsIFile::Clone failed");
            // failure to clone is not fatal (GetFile will generate mFile)
            mFile = 0;
        }
    }
    return rv;
}

//----------------------------------------------------------------------------
// nsStandardURL::nsIStandardURL
//----------------------------------------------------------------------------

inline bool
IsUTFCharset(const char *aCharset)
{
    return ((aCharset[0] == 'U' || aCharset[0] == 'u') &&
            (aCharset[1] == 'T' || aCharset[1] == 't') &&
            (aCharset[2] == 'F' || aCharset[2] == 'f'));
}

NS_IMETHODIMP
nsStandardURL::Init(uint32_t urlType,
                    int32_t defaultPort,
                    const nsACString &spec,
                    const char *charset,
                    nsIURI *baseURI)
{
    ENSURE_MUTABLE();

    if (spec.Length() > (uint32_t) net_GetURLMaxLength()) {
        return NS_ERROR_MALFORMED_URI;
    }

    InvalidateCache();

    switch (urlType) {
    case URLTYPE_STANDARD:
        mParser = net_GetStdURLParser();
        break;
    case URLTYPE_AUTHORITY:
        mParser = net_GetAuthURLParser();
        break;
    case URLTYPE_NO_AUTHORITY:
        mParser = net_GetNoAuthURLParser();
        break;
    default:
        NS_NOTREACHED("bad urlType");
        return NS_ERROR_INVALID_ARG;
    }
    mDefaultPort = defaultPort;
    mURLType = urlType;

    mOriginCharset.Truncate();

    if (charset == nullptr || *charset == '\0') {
        // check if baseURI provides an origin charset and use that.
        if (baseURI)
            baseURI->GetOriginCharset(mOriginCharset);

        // URI can't be encoded in UTF-16, UTF-16BE, UTF-16LE, UTF-32,
        // UTF-32-LE, UTF-32LE, UTF-32BE (yet?). Truncate mOriginCharset if
        // it starts with "utf" (since an empty mOriginCharset implies
        // UTF-8, this is safe even if mOriginCharset is UTF-8).

        if (mOriginCharset.Length() > 3 &&
            IsUTFCharset(mOriginCharset.get())) {
            mOriginCharset.Truncate();
        }
    }
    else if (!IsUTFCharset(charset)) {
        mOriginCharset = charset;
    }

    if (baseURI) {
        uint32_t start, end;
        // pull out the scheme and where it ends
        nsresult rv = net_ExtractURLScheme(spec, &start, &end, nullptr);
        if (NS_SUCCEEDED(rv) && spec.Length() > end+2) {
            nsACString::const_iterator slash;
            spec.BeginReading(slash);
            slash.advance(end+1);
            // then check if // follows
            // if it follows, aSpec is really absolute ... 
            // ignore aBaseURI in this case
            if (*slash == '/' && *(++slash) == '/')
                baseURI = nullptr;
        }
    }

    if (!baseURI)
        return SetSpec(spec);

    nsAutoCString buf;
    nsresult rv = baseURI->Resolve(spec, buf);
    if (NS_FAILED(rv)) return rv;

    return SetSpec(buf);
}

NS_IMETHODIMP
nsStandardURL::GetMutable(bool *value)
{
    *value = mMutable;
    return NS_OK;
}

NS_IMETHODIMP
nsStandardURL::SetMutable(bool value)
{
    NS_ENSURE_ARG(mMutable || !value);

    mMutable = value;
    return NS_OK;
}

//----------------------------------------------------------------------------
// nsStandardURL::nsISerializable
//----------------------------------------------------------------------------

NS_IMETHODIMP
nsStandardURL::Read(nsIObjectInputStream *stream)
{
    NS_PRECONDITION(!mHostA, "Shouldn't have cached ASCII host");
    NS_PRECONDITION(mSpecEncoding == eEncoding_Unknown,
                    "Shouldn't have spec encoding here");
    
    nsresult rv;
    
    uint32_t urlType;
    rv = stream->Read32(&urlType);
    if (NS_FAILED(rv)) return rv;
    mURLType = urlType;
    switch (mURLType) {
      case URLTYPE_STANDARD:
        mParser = net_GetStdURLParser();
        break;
      case URLTYPE_AUTHORITY:
        mParser = net_GetAuthURLParser();
        break;
      case URLTYPE_NO_AUTHORITY:
        mParser = net_GetNoAuthURLParser();
        break;
      default:
        NS_NOTREACHED("bad urlType");
        return NS_ERROR_FAILURE;
    }

    rv = stream->Read32((uint32_t *) &mPort);
    if (NS_FAILED(rv)) return rv;

    rv = stream->Read32((uint32_t *) &mDefaultPort);
    if (NS_FAILED(rv)) return rv;

    rv = NS_ReadOptionalCString(stream, mSpec);
    if (NS_FAILED(rv)) return rv;

    rv = ReadSegment(stream, mScheme);
    if (NS_FAILED(rv)) return rv;

    rv = ReadSegment(stream, mAuthority);
    if (NS_FAILED(rv)) return rv;

    rv = ReadSegment(stream, mUsername);
    if (NS_FAILED(rv)) return rv;

    rv = ReadSegment(stream, mPassword);
    if (NS_FAILED(rv)) return rv;

    rv = ReadSegment(stream, mHost);
    if (NS_FAILED(rv)) return rv;

    rv = ReadSegment(stream, mPath);
    if (NS_FAILED(rv)) return rv;

    rv = ReadSegment(stream, mFilepath);
    if (NS_FAILED(rv)) return rv;

    rv = ReadSegment(stream, mDirectory);
    if (NS_FAILED(rv)) return rv;

    rv = ReadSegment(stream, mBasename);
    if (NS_FAILED(rv)) return rv;

    rv = ReadSegment(stream, mExtension);
    if (NS_FAILED(rv)) return rv;

    // handle forward compatibility from older serializations that included mParam
    URLSegment old_param;
    rv = ReadSegment(stream, old_param);
    if (NS_FAILED(rv)) return rv;

    rv = ReadSegment(stream, mQuery);
    if (NS_FAILED(rv)) return rv;

    rv = ReadSegment(stream, mRef);
    if (NS_FAILED(rv)) return rv;

    rv = NS_ReadOptionalCString(stream, mOriginCharset);
    if (NS_FAILED(rv)) return rv;

    bool isMutable;
    rv = stream->ReadBoolean(&isMutable);
    if (NS_FAILED(rv)) return rv;
    mMutable = isMutable;

    bool supportsFileURL;
    rv = stream->ReadBoolean(&supportsFileURL);
    if (NS_FAILED(rv)) return rv;
    mSupportsFileURL = supportsFileURL;

    uint32_t hostEncoding;
    rv = stream->Read32(&hostEncoding);
    if (NS_FAILED(rv)) return rv;
    if (hostEncoding != eEncoding_ASCII && hostEncoding != eEncoding_UTF8) {
        NS_WARNING("Unexpected host encoding");
        return NS_ERROR_UNEXPECTED;
    }
    mHostEncoding = hostEncoding;

    // wait until object is set up, then modify path to include the param
    if (old_param.mLen >= 0) {  // note that mLen=0 is ";"
        // If this wasn't empty, it marks characters between the end of the 
        // file and start of the query - mPath should include the param,
        // query and ref already.  Bump the mFilePath and 
        // directory/basename/extension components to include this.
        mFilepath.Merge(mSpec,  ';', old_param);
        mDirectory.Merge(mSpec, ';', old_param);
        mBasename.Merge(mSpec,  ';', old_param);
        mExtension.Merge(mSpec, ';', old_param);
    }
    
    return NS_OK;
}

NS_IMETHODIMP
nsStandardURL::Write(nsIObjectOutputStream *stream)
{
    nsresult rv;

    rv = stream->Write32(mURLType);
    if (NS_FAILED(rv)) return rv;

    rv = stream->Write32(uint32_t(mPort));
    if (NS_FAILED(rv)) return rv;

    rv = stream->Write32(uint32_t(mDefaultPort));
    if (NS_FAILED(rv)) return rv;

    rv = NS_WriteOptionalStringZ(stream, mSpec.get());
    if (NS_FAILED(rv)) return rv;

    rv = WriteSegment(stream, mScheme);
    if (NS_FAILED(rv)) return rv;

    rv = WriteSegment(stream, mAuthority);
    if (NS_FAILED(rv)) return rv;

    rv = WriteSegment(stream, mUsername);
    if (NS_FAILED(rv)) return rv;

    rv = WriteSegment(stream, mPassword);
    if (NS_FAILED(rv)) return rv;

    rv = WriteSegment(stream, mHost);
    if (NS_FAILED(rv)) return rv;

    rv = WriteSegment(stream, mPath);
    if (NS_FAILED(rv)) return rv;

    rv = WriteSegment(stream, mFilepath);
    if (NS_FAILED(rv)) return rv;

    rv = WriteSegment(stream, mDirectory);
    if (NS_FAILED(rv)) return rv;

    rv = WriteSegment(stream, mBasename);
    if (NS_FAILED(rv)) return rv;

    rv = WriteSegment(stream, mExtension);
    if (NS_FAILED(rv)) return rv;

    // for backwards compatibility since we removed mParam.  Note that this will mean that
    // an older browser will read "" for mParam, and the param(s) will be part of mPath (as they
    // after the removal of special handling).  It only matters if you downgrade a browser to before
    // the patch.
    URLSegment empty;
    rv = WriteSegment(stream, empty);
    if (NS_FAILED(rv)) return rv;

    rv = WriteSegment(stream, mQuery);
    if (NS_FAILED(rv)) return rv;

    rv = WriteSegment(stream, mRef);
    if (NS_FAILED(rv)) return rv;

    rv = NS_WriteOptionalStringZ(stream, mOriginCharset.get());
    if (NS_FAILED(rv)) return rv;

    rv = stream->WriteBoolean(mMutable);
    if (NS_FAILED(rv)) return rv;

    rv = stream->WriteBoolean(mSupportsFileURL);
    if (NS_FAILED(rv)) return rv;

    rv = stream->Write32(mHostEncoding);
    if (NS_FAILED(rv)) return rv;

    // mSpecEncoding and mHostA are just caches that can be recovered as needed.

    return NS_OK;
}

//---------------------------------------------------------------------------
// nsStandardURL::nsIIPCSerializableURI
//---------------------------------------------------------------------------

inline
mozilla::ipc::StandardURLSegment
ToIPCSegment(const nsStandardURL::URLSegment& aSegment)
{
    return mozilla::ipc::StandardURLSegment(aSegment.mPos, aSegment.mLen);
}

inline
nsStandardURL::URLSegment
FromIPCSegment(const mozilla::ipc::StandardURLSegment& aSegment)
{
    return nsStandardURL::URLSegment(aSegment.position(), aSegment.length());
}

void
nsStandardURL::Serialize(URIParams& aParams)
{
    StandardURLParams params;

    params.urlType() = mURLType;
    params.port() = mPort;
    params.defaultPort() = mDefaultPort;
    params.spec() = mSpec;
    params.scheme() = ToIPCSegment(mScheme);
    params.authority() = ToIPCSegment(mAuthority);
    params.username() = ToIPCSegment(mUsername);
    params.password() = ToIPCSegment(mPassword);
    params.host() = ToIPCSegment(mHost);
    params.path() = ToIPCSegment(mPath);
    params.filePath() = ToIPCSegment(mFilepath);
    params.directory() = ToIPCSegment(mDirectory);
    params.baseName() = ToIPCSegment(mBasename);
    params.extension() = ToIPCSegment(mExtension);
    params.query() = ToIPCSegment(mQuery);
    params.ref() = ToIPCSegment(mRef);
    params.originCharset() = mOriginCharset;
    params.isMutable() = !!mMutable;
    params.supportsFileURL() = !!mSupportsFileURL;
    params.hostEncoding() = mHostEncoding;
    // mSpecEncoding and mHostA are just caches that can be recovered as needed.

    aParams = params;
}

bool
nsStandardURL::Deserialize(const URIParams& aParams)
{
    NS_PRECONDITION(!mHostA, "Shouldn't have cached ASCII host");
    NS_PRECONDITION(mSpecEncoding == eEncoding_Unknown,
                    "Shouldn't have spec encoding here");
    NS_PRECONDITION(!mFile, "Shouldn't have cached file");

    if (aParams.type() != URIParams::TStandardURLParams) {
        NS_ERROR("Received unknown parameters from the other process!");
        return false;
    }

    const StandardURLParams& params = aParams.get_StandardURLParams();

    mURLType = params.urlType();
    switch (mURLType) {
        case URLTYPE_STANDARD:
            mParser = net_GetStdURLParser();
            break;
        case URLTYPE_AUTHORITY:
            mParser = net_GetAuthURLParser();
            break;
        case URLTYPE_NO_AUTHORITY:
            mParser = net_GetNoAuthURLParser();
            break;
        default:
            NS_NOTREACHED("bad urlType");
            return false;
    }

    if (params.hostEncoding() != eEncoding_ASCII &&
        params.hostEncoding() != eEncoding_UTF8) {
        NS_WARNING("Unexpected host encoding");
        return false;
    }

    mPort = params.port();
    mDefaultPort = params.defaultPort();
    mSpec = params.spec();
    mScheme = FromIPCSegment(params.scheme());
    mAuthority = FromIPCSegment(params.authority());
    mUsername = FromIPCSegment(params.username());
    mPassword = FromIPCSegment(params.password());
    mHost = FromIPCSegment(params.host());
    mPath = FromIPCSegment(params.path());
    mFilepath = FromIPCSegment(params.filePath());
    mDirectory = FromIPCSegment(params.directory());
    mBasename = FromIPCSegment(params.baseName());
    mExtension = FromIPCSegment(params.extension());
    mQuery = FromIPCSegment(params.query());
    mRef = FromIPCSegment(params.ref());
    mOriginCharset = params.originCharset();
    mMutable = params.isMutable();
    mSupportsFileURL = params.supportsFileURL();
    mHostEncoding = params.hostEncoding();

    // mSpecEncoding and mHostA are just caches that can be recovered as needed.
    return true;
}

//----------------------------------------------------------------------------
// nsStandardURL::nsIClassInfo
//----------------------------------------------------------------------------

NS_IMETHODIMP 
nsStandardURL::GetInterfaces(uint32_t *count, nsIID * **array)
{
    *count = 0;
    *array = nullptr;
    return NS_OK;
}

NS_IMETHODIMP 
nsStandardURL::GetScriptableHelper(nsIXPCScriptable **_retval)
{
    *_retval = nullptr;
    return NS_OK;
}

NS_IMETHODIMP 
nsStandardURL::GetContractID(char * *aContractID)
{
    *aContractID = nullptr;
    return NS_OK;
}

NS_IMETHODIMP 
nsStandardURL::GetClassDescription(char * *aClassDescription)
{
    *aClassDescription = nullptr;
    return NS_OK;
}

NS_IMETHODIMP 
nsStandardURL::GetClassID(nsCID * *aClassID)
{
    *aClassID = (nsCID*) moz_xmalloc(sizeof(nsCID));
    if (!*aClassID)
        return NS_ERROR_OUT_OF_MEMORY;
    return GetClassIDNoAlloc(*aClassID);
}

NS_IMETHODIMP 
nsStandardURL::GetFlags(uint32_t *aFlags)
{
    *aFlags = nsIClassInfo::MAIN_THREAD_ONLY;
    return NS_OK;
}

NS_IMETHODIMP 
nsStandardURL::GetClassIDNoAlloc(nsCID *aClassIDNoAlloc)
{
    *aClassIDNoAlloc = kStandardURLCID;
    return NS_OK;
}

//----------------------------------------------------------------------------
// nsStandardURL::nsISizeOf
//----------------------------------------------------------------------------

size_t
nsStandardURL::SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) const
{
  return mSpec.SizeOfExcludingThisIfUnshared(aMallocSizeOf) +
         mOriginCharset.SizeOfExcludingThisIfUnshared(aMallocSizeOf) +
         aMallocSizeOf(mHostA);

  // Measurement of the following members may be added later if DMD finds it is
  // worthwhile:
  // - mParser
  // - mFile
}

size_t
nsStandardURL::SizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf) const {
  return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf);
}