/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ /* ***** BEGIN LICENSE BLOCK ***** * Version: MPL 1.1/GPL 2.0/LGPL 2.1 * * The contents of this file are subject to the Mozilla Public License Version * 1.1 (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * http://www.mozilla.org/MPL/ * * Software distributed under the License is distributed on an "AS IS" basis, * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License * for the specific language governing rights and limitations under the * License. * * The Original Code is mozilla.org code. * * The Initial Developer of the Original Code is * Netscape Communications Corporation. * Portions created by the Initial Developer are Copyright (C) 1998 * the Initial Developer. All Rights Reserved. * * Contributor(s): * L. David Baron * Daniel Glazman * * Alternatively, the contents of this file may be used under the terms of * either of the GNU General Public License Version 2 or later (the "GPL"), * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"), * in which case the provisions of the GPL or the LGPL are applicable instead * of those above. If you wish to allow use of your version of this file only * under the terms of either the GPL or the LGPL, and not to allow others to * use your version of this file under the terms of the MPL, indicate your * decision by deleting the provisions above and replace them with the notice * and other provisions required by the GPL or the LGPL. If you do not delete * the provisions above, a recipient may use your version of this file under * the terms of any one of the MPL, the GPL or the LGPL. * * ***** END LICENSE BLOCK ***** */ #include /* tokenization of CSS style sheets */ #include "nsCSSScanner.h" #include "nsIFactory.h" #include "nsIInputStream.h" #include "nsIUnicharInputStream.h" #include "nsString.h" #include "nsCRT.h" // for #ifdef CSS_REPORT_PARSE_ERRORS #include "nsCOMPtr.h" #include "nsIServiceManager.h" #include "nsIComponentManager.h" #include "nsReadableUtils.h" #include "nsIURI.h" #include "nsIConsoleService.h" #include "nsIScriptError.h" #include "nsIStringBundle.h" #include "nsContentUtils.h" // Don't bother collecting whitespace characters in token's mIdent buffer #undef COLLECT_WHITESPACE static const PRUnichar CSS_ESCAPE = PRUnichar('\\'); static const PRUint8 IS_DIGIT = 0x01; static const PRUint8 IS_HEX_DIGIT = 0x02; static const PRUint8 START_IDENT = 0x04; static const PRUint8 IS_IDENT = 0x08; static const PRUint8 IS_WHITESPACE = 0x10; static PRBool gLexTableSetup = PR_FALSE; static PRUint8 gLexTable[256]; #ifdef CSS_REPORT_PARSE_ERRORS static PRBool gReportErrors = PR_TRUE; static nsIConsoleService *gConsoleService; static nsIFactory *gScriptErrorFactory; static nsIStringBundle *gStringBundle; #endif static void BuildLexTable() { gLexTableSetup = PR_TRUE; PRUint8* lt = gLexTable; int i; lt[CSS_ESCAPE] = START_IDENT; lt['-'] |= IS_IDENT; lt['_'] |= IS_IDENT | START_IDENT; lt[' '] |= IS_WHITESPACE; // space lt['\t'] |= IS_WHITESPACE; // horizontal tab lt['\r'] |= IS_WHITESPACE; // carriage return lt['\n'] |= IS_WHITESPACE; // line feed lt['\f'] |= IS_WHITESPACE; // form feed for (i = 161; i <= 255; i++) { lt[i] |= IS_IDENT | START_IDENT; } for (i = '0'; i <= '9'; i++) { lt[i] |= IS_DIGIT | IS_HEX_DIGIT | IS_IDENT; } for (i = 'A'; i <= 'Z'; i++) { if ((i >= 'A') && (i <= 'F')) { lt[i] |= IS_HEX_DIGIT; lt[i+32] |= IS_HEX_DIGIT; } lt[i] |= IS_IDENT | START_IDENT; lt[i+32] |= IS_IDENT | START_IDENT; } } static inline PRBool IsIdentStart(PRInt32 aChar) { return aChar >= 0 && (aChar >= 256 || (gLexTable[aChar] & START_IDENT) != 0); } static inline PRBool StartsIdent(PRInt32 aFirstChar, PRInt32 aSecondChar) { return IsIdentStart(aFirstChar) || (aFirstChar == '-' && IsIdentStart(aSecondChar)); } static inline PRBool IsWhitespace(PRInt32 ch) { return PRUint32(ch) < 256 && (gLexTable[ch] & IS_WHITESPACE) != 0; } static inline PRBool IsDigit(PRInt32 ch) { return PRUint32(ch) < 256 && (gLexTable[ch] & IS_DIGIT) != 0; } static inline PRBool IsHexDigit(PRInt32 ch) { return PRUint32(ch) < 256 && (gLexTable[ch] & IS_HEX_DIGIT) != 0; } static inline PRBool IsIdent(PRInt32 ch) { return ch >= 0 && (ch >= 256 || (gLexTable[ch] & IS_IDENT) != 0); } nsCSSToken::nsCSSToken() { mType = eCSSToken_Symbol; } void nsCSSToken::AppendToString(nsString& aBuffer) { switch (mType) { case eCSSToken_AtKeyword: aBuffer.Append(PRUnichar('@')); // fall through intentional case eCSSToken_Ident: case eCSSToken_WhiteSpace: case eCSSToken_Function: case eCSSToken_URL: case eCSSToken_InvalidURL: case eCSSToken_HTMLComment: aBuffer.Append(mIdent); break; case eCSSToken_Number: if (mIntegerValid) { aBuffer.AppendInt(mInteger, 10); } else { aBuffer.AppendFloat(mNumber); } break; case eCSSToken_Percentage: NS_ASSERTION(!mIntegerValid, "How did a percentage token get this set?"); aBuffer.AppendFloat(mNumber * 100.0f); aBuffer.Append(PRUnichar('%')); // STRING USE WARNING: technically, this should be |AppendWithConversion| break; case eCSSToken_Dimension: if (mIntegerValid) { aBuffer.AppendInt(mInteger, 10); } else { aBuffer.AppendFloat(mNumber); } aBuffer.Append(mIdent); break; case eCSSToken_String: aBuffer.Append(mSymbol); aBuffer.Append(mIdent); // fall through intentional case eCSSToken_Symbol: aBuffer.Append(mSymbol); break; case eCSSToken_ID: case eCSSToken_Ref: aBuffer.Append(PRUnichar('#')); aBuffer.Append(mIdent); break; case eCSSToken_Includes: aBuffer.AppendLiteral("~="); break; case eCSSToken_Dashmatch: aBuffer.AppendLiteral("|="); break; case eCSSToken_Beginsmatch: aBuffer.AppendLiteral("^="); break; case eCSSToken_Endsmatch: aBuffer.AppendLiteral("$="); break; case eCSSToken_Containsmatch: aBuffer.AppendLiteral("*="); break; case eCSSToken_Error: aBuffer.Append(mSymbol); aBuffer.Append(mIdent); break; default: NS_ERROR("invalid token type"); break; } } nsCSSScanner::nsCSSScanner() : mInputStream(nsnull) , mReadPointer(nsnull) , mLowLevelError(NS_OK) #ifdef MOZ_SVG , mSVGMode(PR_FALSE) #endif #ifdef CSS_REPORT_PARSE_ERRORS , mError(mErrorBuf, NS_ARRAY_LENGTH(mErrorBuf), 0) #endif { MOZ_COUNT_CTOR(nsCSSScanner); if (!gLexTableSetup) { // XXX need a monitor BuildLexTable(); } mPushback = mLocalPushback; mPushbackSize = NS_ARRAY_LENGTH(mLocalPushback); // No need to init the other members, since they represent state // which can get cleared. We'll init them every time Init() is // called. } nsCSSScanner::~nsCSSScanner() { MOZ_COUNT_DTOR(nsCSSScanner); Close(); if (mLocalPushback != mPushback) { delete [] mPushback; } } nsresult nsCSSScanner::GetLowLevelError() { return mLowLevelError; } void nsCSSScanner::SetLowLevelError(nsresult aErrorCode) { NS_ASSERTION(aErrorCode != NS_OK, "SetLowLevelError() used to clear error"); NS_ASSERTION(mLowLevelError == NS_OK, "there is already a low-level error"); mLowLevelError = aErrorCode; } #ifdef CSS_REPORT_PARSE_ERRORS #define CSS_ERRORS_PREF "layout.css.report_errors" static int CSSErrorsPrefChanged(const char *aPref, void *aClosure) { gReportErrors = nsContentUtils::GetBoolPref(CSS_ERRORS_PREF, PR_TRUE); return NS_OK; } #endif /* static */ PRBool nsCSSScanner::InitGlobals() { #ifdef CSS_REPORT_PARSE_ERRORS if (gConsoleService && gScriptErrorFactory) return PR_TRUE; nsresult rv = CallGetService(NS_CONSOLESERVICE_CONTRACTID, &gConsoleService); NS_ENSURE_SUCCESS(rv, PR_FALSE); rv = CallGetClassObject(NS_SCRIPTERROR_CONTRACTID, &gScriptErrorFactory); NS_ENSURE_SUCCESS(rv, PR_FALSE); NS_ASSERTION(gConsoleService && gScriptErrorFactory, "unexpected null pointer without failure"); nsContentUtils::RegisterPrefCallback(CSS_ERRORS_PREF, CSSErrorsPrefChanged, nsnull); CSSErrorsPrefChanged(CSS_ERRORS_PREF, nsnull); #endif return PR_TRUE; } /* static */ void nsCSSScanner::ReleaseGlobals() { #ifdef CSS_REPORT_PARSE_ERRORS nsContentUtils::UnregisterPrefCallback(CSS_ERRORS_PREF, CSSErrorsPrefChanged, nsnull); NS_IF_RELEASE(gConsoleService); NS_IF_RELEASE(gScriptErrorFactory); NS_IF_RELEASE(gStringBundle); #endif } void nsCSSScanner::Init(nsIUnicharInputStream* aInput, const PRUnichar * aBuffer, PRUint32 aCount, nsIURI* aURI, PRUint32 aLineNumber) { NS_PRECONDITION(!mInputStream, "Should not have an existing input stream!"); NS_PRECONDITION(!mReadPointer, "Should not have an existing input buffer!"); // Read from stream via my own buffer if (aInput) { NS_PRECONDITION(!aBuffer, "Shouldn't have both input and buffer!"); NS_PRECONDITION(aCount == 0, "Shouldn't have count with a stream"); mInputStream = aInput; mReadPointer = mBuffer; mCount = 0; } else { NS_PRECONDITION(aBuffer, "Either aInput or aBuffer must be set"); // Read directly from the provided buffer mInputStream = nsnull; mReadPointer = aBuffer; mCount = aCount; } #ifdef CSS_REPORT_PARSE_ERRORS // If aURI is the same as mURI, no need to reget mFileName -- it // shouldn't have changed. if (aURI != mURI) { mURI = aURI; if (aURI) { aURI->GetSpec(mFileName); } else { mFileName.Adopt(NS_strdup("from DOM")); } } #endif // CSS_REPORT_PARSE_ERRORS mLineNumber = aLineNumber; // Reset variables that we use to keep track of our progress through the input mOffset = 0; mPushbackCount = 0; mLowLevelError = NS_OK; #ifdef CSS_REPORT_PARSE_ERRORS mColNumber = 0; #endif } #ifdef CSS_REPORT_PARSE_ERRORS // @see REPORT_UNEXPECTED_EOF in nsCSSParser.cpp #define REPORT_UNEXPECTED_EOF(lf_) \ ReportUnexpectedEOF(#lf_) void nsCSSScanner::AddToError(const nsSubstring& aErrorText) { if (mError.IsEmpty()) { mErrorLineNumber = mLineNumber; mErrorColNumber = mColNumber; mError = aErrorText; } else { mError.Append(NS_LITERAL_STRING(" ") + aErrorText); } } void nsCSSScanner::ClearError() { mError.Truncate(); } void nsCSSScanner::OutputError() { if (mError.IsEmpty()) return; // Log it to the Error console if (InitGlobals() && gReportErrors) { nsresult rv; nsCOMPtr errorObject = do_CreateInstance(gScriptErrorFactory, &rv); if (NS_SUCCEEDED(rv)) { rv = errorObject->Init(mError.get(), NS_ConvertUTF8toUTF16(mFileName).get(), EmptyString().get(), mErrorLineNumber, mErrorColNumber, nsIScriptError::warningFlag, "CSS Parser"); if (NS_SUCCEEDED(rv)) gConsoleService->LogMessage(errorObject); } } ClearError(); } static PRBool InitStringBundle() { if (gStringBundle) return PR_TRUE; nsCOMPtr sbs = do_GetService(NS_STRINGBUNDLE_CONTRACTID); if (!sbs) return PR_FALSE; nsresult rv = sbs->CreateBundle("chrome://global/locale/css.properties", &gStringBundle); if (NS_FAILED(rv)) { gStringBundle = nsnull; return PR_FALSE; } return PR_TRUE; } #define ENSURE_STRINGBUNDLE \ PR_BEGIN_MACRO if (!InitStringBundle()) return; PR_END_MACRO // aMessage must take no parameters void nsCSSScanner::ReportUnexpected(const char* aMessage) { ENSURE_STRINGBUNDLE; nsXPIDLString str; gStringBundle->GetStringFromName(NS_ConvertASCIItoUTF16(aMessage).get(), getter_Copies(str)); AddToError(str); } void nsCSSScanner::ReportUnexpectedParams(const char* aMessage, const PRUnichar **aParams, PRUint32 aParamsLength) { NS_PRECONDITION(aParamsLength > 0, "use the non-params version"); ENSURE_STRINGBUNDLE; nsXPIDLString str; gStringBundle->FormatStringFromName(NS_ConvertASCIItoUTF16(aMessage).get(), aParams, aParamsLength, getter_Copies(str)); AddToError(str); } // aLookingFor is a plain string, not a format string void nsCSSScanner::ReportUnexpectedEOF(const char* aLookingFor) { ENSURE_STRINGBUNDLE; nsXPIDLString innerStr; gStringBundle->GetStringFromName(NS_ConvertASCIItoUTF16(aLookingFor).get(), getter_Copies(innerStr)); const PRUnichar *params[] = { innerStr.get() }; nsXPIDLString str; gStringBundle->FormatStringFromName(NS_LITERAL_STRING("PEUnexpEOF2").get(), params, NS_ARRAY_LENGTH(params), getter_Copies(str)); AddToError(str); } // aLookingFor is a single character void nsCSSScanner::ReportUnexpectedEOF(PRUnichar aLookingFor) { ENSURE_STRINGBUNDLE; const PRUnichar lookingForStr[] = { PRUnichar('\''), aLookingFor, PRUnichar('\''), PRUnichar(0) }; const PRUnichar *params[] = { lookingForStr }; nsXPIDLString str; gStringBundle->FormatStringFromName(NS_LITERAL_STRING("PEUnexpEOF2").get(), params, NS_ARRAY_LENGTH(params), getter_Copies(str)); AddToError(str); } // aMessage must take 1 parameter (for the string representation of the // unexpected token) void nsCSSScanner::ReportUnexpectedToken(nsCSSToken& tok, const char *aMessage) { ENSURE_STRINGBUNDLE; nsAutoString tokenString; tok.AppendToString(tokenString); const PRUnichar *params[] = { tokenString.get() }; ReportUnexpectedParams(aMessage, params, NS_ARRAY_LENGTH(params)); } // aParams's first entry must be null, and we'll fill in the token void nsCSSScanner::ReportUnexpectedTokenParams(nsCSSToken& tok, const char* aMessage, const PRUnichar **aParams, PRUint32 aParamsLength) { NS_PRECONDITION(aParamsLength > 1, "use the non-params version"); NS_PRECONDITION(aParams[0] == nsnull, "first param should be empty"); ENSURE_STRINGBUNDLE; nsAutoString tokenString; tok.AppendToString(tokenString); aParams[0] = tokenString.get(); ReportUnexpectedParams(aMessage, aParams, aParamsLength); } #else #define REPORT_UNEXPECTED_EOF(lf_) #endif // CSS_REPORT_PARSE_ERRORS void nsCSSScanner::Close() { mInputStream = nsnull; mReadPointer = nsnull; // Clean things up so we don't hold on to memory if our parser gets recycled. #ifdef CSS_REPORT_PARSE_ERRORS mFileName.Truncate(); mURI = nsnull; mError.Truncate(); #endif if (mPushback != mLocalPushback) { delete [] mPushback; mPushback = mLocalPushback; mPushbackSize = NS_ARRAY_LENGTH(mLocalPushback); } } #ifdef CSS_REPORT_PARSE_ERRORS #define TAB_STOP_WIDTH 8 #endif PRBool nsCSSScanner::EnsureData() { if (mOffset < mCount) return PR_TRUE; if (!mInputStream) return PR_FALSE; mOffset = 0; nsresult rv = mInputStream->Read(mBuffer, CSS_BUFFER_SIZE, &mCount); if (NS_FAILED(rv)) { mCount = 0; SetLowLevelError(rv); return PR_FALSE; } return mCount > 0; } // Returns -1 on error or eof PRInt32 nsCSSScanner::Read() { PRInt32 rv; if (0 < mPushbackCount) { rv = PRInt32(mPushback[--mPushbackCount]); } else { if (mOffset == mCount && !EnsureData()) { return -1; } rv = PRInt32(mReadPointer[mOffset++]); // There are four types of newlines in CSS: "\r", "\n", "\r\n", and "\f". // To simplify dealing with newlines, they are all normalized to "\n" here if (rv == '\r') { if (EnsureData() && mReadPointer[mOffset] == '\n') { mOffset++; } rv = '\n'; } else if (rv == '\f') { rv = '\n'; } if (rv == '\n') { // 0 is a magical line number meaning that we don't know (i.e., script) if (mLineNumber != 0) ++mLineNumber; #ifdef CSS_REPORT_PARSE_ERRORS mColNumber = 0; #endif } #ifdef CSS_REPORT_PARSE_ERRORS else if (rv == '\t') { mColNumber = ((mColNumber - 1 + TAB_STOP_WIDTH) / TAB_STOP_WIDTH) * TAB_STOP_WIDTH; } else if (rv != '\n') { mColNumber++; } #endif } //printf("Read => %x\n", rv); return rv; } PRInt32 nsCSSScanner::Peek() { if (0 == mPushbackCount) { PRInt32 ch = Read(); if (ch < 0) { return -1; } mPushback[0] = PRUnichar(ch); mPushbackCount++; } //printf("Peek => %x\n", mLookAhead); return PRInt32(mPushback[mPushbackCount - 1]); } void nsCSSScanner::Pushback(PRUnichar aChar) { if (mPushbackCount == mPushbackSize) { // grow buffer PRUnichar* newPushback = new PRUnichar[mPushbackSize + 4]; if (nsnull == newPushback) { return; } mPushbackSize += 4; memcpy(newPushback, mPushback, sizeof(PRUnichar) * mPushbackCount); if (mPushback != mLocalPushback) { delete [] mPushback; } mPushback = newPushback; } mPushback[mPushbackCount++] = aChar; } PRBool nsCSSScanner::LookAhead(PRUnichar aChar) { PRInt32 ch = Read(); if (ch < 0) { return PR_FALSE; } if (ch == aChar) { return PR_TRUE; } Pushback(ch); return PR_FALSE; } void nsCSSScanner::EatWhiteSpace() { for (;;) { PRInt32 ch = Read(); if (ch < 0) { break; } if ((ch != ' ') && (ch != '\n') && (ch != '\t')) { Pushback(ch); break; } } } PRBool nsCSSScanner::Next(nsCSSToken& aToken) { for (;;) { // Infinite loop so we can restart after comments. PRInt32 ch = Read(); if (ch < 0) { return PR_FALSE; } // IDENT if (StartsIdent(ch, Peek())) return ParseIdent(ch, aToken); // AT_KEYWORD if (ch == '@') { PRInt32 nextChar = Read(); if (nextChar >= 0) { PRInt32 followingChar = Peek(); Pushback(nextChar); if (StartsIdent(nextChar, followingChar)) return ParseAtKeyword(ch, aToken); } } // NUMBER or DIM if ((ch == '.') || (ch == '+') || (ch == '-')) { PRInt32 nextChar = Peek(); if (IsDigit(nextChar)) { return ParseNumber(ch, aToken); } else if (('.' == nextChar) && ('.' != ch)) { nextChar = Read(); PRInt32 followingChar = Peek(); Pushback(nextChar); if (IsDigit(followingChar)) return ParseNumber(ch, aToken); } } if (IsDigit(ch)) { return ParseNumber(ch, aToken); } // ID if (ch == '#') { return ParseRef(ch, aToken); } // STRING if ((ch == '"') || (ch == '\'')) { return ParseString(ch, aToken); } // WS if (IsWhitespace(ch)) { aToken.mType = eCSSToken_WhiteSpace; aToken.mIdent.Assign(PRUnichar(ch)); EatWhiteSpace(); return PR_TRUE; } if (ch == '/') { PRInt32 nextChar = Peek(); if (nextChar == '*') { (void) Read(); #if 0 // If we change our storage data structures such that comments are // stored (for Editor), we should reenable this code, condition it // on being in editor mode, and apply glazou's patch from bug // 60290. aToken.mIdent.SetCapacity(2); aToken.mIdent.Assign(PRUnichar(ch)); aToken.mIdent.Append(PRUnichar(nextChar)); return ParseCComment(aToken); #endif if (!SkipCComment()) { return PR_FALSE; } continue; // start again at the beginning } } if (ch == '<') { // consume HTML comment tags if (LookAhead('!')) { if (LookAhead('-')) { if (LookAhead('-')) { aToken.mType = eCSSToken_HTMLComment; aToken.mIdent.AssignLiteral(""); return PR_TRUE; } Pushback('-'); } } // INCLUDES ("~=") and DASHMATCH ("|=") if (( ch == '|' ) || ( ch == '~' ) || ( ch == '^' ) || ( ch == '$' ) || ( ch == '*' )) { PRInt32 nextChar = Read(); if ( nextChar == '=' ) { if (ch == '~') { aToken.mType = eCSSToken_Includes; } else if (ch == '|') { aToken.mType = eCSSToken_Dashmatch; } else if (ch == '^') { aToken.mType = eCSSToken_Beginsmatch; } else if (ch == '$') { aToken.mType = eCSSToken_Endsmatch; } else if (ch == '*') { aToken.mType = eCSSToken_Containsmatch; } return PR_TRUE; } else if (nextChar >= 0) { Pushback(nextChar); } } aToken.mType = eCSSToken_Symbol; aToken.mSymbol = ch; return PR_TRUE; } } PRBool nsCSSScanner::NextURL(nsCSSToken& aToken) { PRInt32 ch = Read(); if (ch < 0) { return PR_FALSE; } // STRING if ((ch == '"') || (ch == '\'')) { return ParseString(ch, aToken); } // WS if (IsWhitespace(ch)) { aToken.mType = eCSSToken_WhiteSpace; aToken.mIdent.Assign(PRUnichar(ch)); EatWhiteSpace(); return PR_TRUE; } // Process a url lexical token. A CSS1 url token can contain // characters beyond identifier characters (e.g. '/', ':', etc.) // Because of this the normal rules for tokenizing the input don't // apply very well. To simplify the parser and relax some of the // requirements on the scanner we parse url's here. If we find a // malformed URL then we emit a token of type "InvalidURL" so that // the CSS1 parser can ignore the invalid input. We attempt to eat // the right amount of input data when an invalid URL is presented. aToken.mType = eCSSToken_InvalidURL; nsString& ident = aToken.mIdent; ident.SetLength(0); if (ch == ')') { Pushback(ch); // empty url spec; just get out of here aToken.mType = eCSSToken_URL; } else { // start of a non-quoted url Pushback(ch); PRBool ok = PR_TRUE; for (;;) { ch = Read(); if (ch < 0) break; if (ch == CSS_ESCAPE) { ParseAndAppendEscape(ident); } else if ((ch == '"') || (ch == '\'') || (ch == '(')) { // This is an invalid URL spec ok = PR_FALSE; } else if (IsWhitespace(ch)) { // Whitespace is allowed at the end of the URL EatWhiteSpace(); if (LookAhead(')')) { Pushback(')'); // leave the closing symbol // done! break; } // Whitespace is followed by something other than a // ")". This is an invalid url spec. ok = PR_FALSE; } else if (ch == ')') { Pushback(ch); // All done break; } else { // A regular url character. ident.Append(PRUnichar(ch)); } } // If the result of the above scanning is ok then change the token // type to a useful one. if (ok) { aToken.mType = eCSSToken_URL; } } return PR_TRUE; } void nsCSSScanner::ParseAndAppendEscape(nsString& aOutput) { PRInt32 ch = Peek(); if (ch < 0) { aOutput.Append(CSS_ESCAPE); return; } if (IsHexDigit(ch)) { PRInt32 rv = 0; int i; for (i = 0; i < 6; i++) { // up to six digits ch = Read(); if (ch < 0) { // Whoops: error or premature eof break; } if (!IsHexDigit(ch) && !IsWhitespace(ch)) { Pushback(ch); break; } else if (IsHexDigit(ch)) { if (IsDigit(ch)) { rv = rv * 16 + (ch - '0'); } else { // Note: c&7 just keeps the low three bits which causes // upper and lower case alphabetics to both yield their // "relative to 10" value for computing the hex value. rv = rv * 16 + ((ch & 0x7) + 9); } } else { NS_ASSERTION(IsWhitespace(ch), "bad control flow"); // single space ends escape break; } } if (6 == i) { // look for trailing whitespace and eat it ch = Peek(); if (IsWhitespace(ch)) { (void) Read(); } } NS_ASSERTION(rv >= 0, "How did rv become negative?"); // "[at most six hexadecimal digits following a backslash] stand // for the ISO 10646 character with that number, which must not be // zero. (It is undefined in CSS 2.1 what happens if a style sheet // does contain a character with Unicode codepoint zero.)" // -- CSS2.1 section 4.1.3 // // Silently deleting \0 opens a content-filtration loophole (see // bug 228856), so what we do instead is pretend the "cancels the // meaning of special characters" rule applied. if (rv > 0) { AppendUCS4ToUTF16(ENSURE_VALID_CHAR(rv), aOutput); } else { while (i--) aOutput.Append('0'); if (IsWhitespace(ch)) Pushback(ch); } return; } // "Any character except a hexidecimal digit can be escaped to // remove its special meaning by putting a backslash in front" // -- CSS1 spec section 7.1 ch = Read(); // Consume the escaped character if ((ch > 0) && (ch != '\n')) { aOutput.Append(ch); } } /** * Gather up the characters in an identifier. The identfier was * started by "aChar" which will be appended to aIdent. The result * will be aIdent with all of the identifier characters appended * until the first non-identifier character is seen. The termination * character is unread for the future re-reading. */ PRBool nsCSSScanner::GatherIdent(PRInt32 aChar, nsString& aIdent) { if (aChar == CSS_ESCAPE) { ParseAndAppendEscape(aIdent); } else if (0 < aChar) { aIdent.Append(aChar); } for (;;) { // If nothing in pushback, first try to get as much as possible in one go if (!mPushbackCount && EnsureData()) { // See how much we can consume and append in one go PRUint32 n = mOffset; // Count number of Ident characters that can be processed while (n < mCount && IsIdent(mReadPointer[n])) { ++n; } // Add to the token what we have so far if (n > mOffset) { #ifdef CSS_REPORT_PARSE_ERRORS mColNumber += n - mOffset; #endif aIdent.Append(&mReadPointer[mOffset], n - mOffset); mOffset = n; } } aChar = Read(); if (aChar < 0) break; if (aChar == CSS_ESCAPE) { ParseAndAppendEscape(aIdent); } else if (IsIdent(aChar)) { aIdent.Append(PRUnichar(aChar)); } else { Pushback(aChar); break; } } return PR_TRUE; } PRBool nsCSSScanner::ParseRef(PRInt32 aChar, nsCSSToken& aToken) { aToken.mIdent.SetLength(0); aToken.mType = eCSSToken_Ref; PRInt32 ch = Read(); if (ch < 0) { return PR_FALSE; } if (IsIdent(ch) || ch == CSS_ESCAPE) { // First char after the '#' is a valid ident char (or an escape), // so it makes sense to keep going if (StartsIdent(ch, Peek())) { aToken.mType = eCSSToken_ID; } return GatherIdent(ch, aToken.mIdent); } // No ident chars after the '#'. Just unread |ch| and get out of here. Pushback(ch); return PR_TRUE; } PRBool nsCSSScanner::ParseIdent(PRInt32 aChar, nsCSSToken& aToken) { nsString& ident = aToken.mIdent; ident.SetLength(0); if (!GatherIdent(aChar, ident)) { return PR_FALSE; } nsCSSTokenType tokenType = eCSSToken_Ident; // look for functions (ie: "ident(") if (PRUnichar('(') == PRUnichar(Peek())) { // this is a function definition tokenType = eCSSToken_Function; } aToken.mType = tokenType; return PR_TRUE; } PRBool nsCSSScanner::ParseAtKeyword(PRInt32 aChar, nsCSSToken& aToken) { aToken.mIdent.SetLength(0); aToken.mType = eCSSToken_AtKeyword; return GatherIdent(0, aToken.mIdent); } #define CHAR_TO_DIGIT(_c) ((_c) - '0') PRBool nsCSSScanner::ParseNumber(PRInt32 c, nsCSSToken& aToken) { NS_PRECONDITION(c == '.' || c == '+' || c == '-' || IsDigit(c), "Why did we get called?"); aToken.mHasSign = (c == '+' || c == '-'); // Our sign. PRInt32 sign = c == '-' ? -1 : 1; // Absolute value of the integer part of the mantissa. This is a double so // we don't run into overflow issues for consumers that only care about our // floating-point value while still being able to express the full PRInt32 // range for consumers who want integers. double intPart = 0; // Fractional part of the mantissa. This is a double so that when we convert // to float at the end we'll end up rounding to nearest float instead of // truncating down (as we would if fracPart were a float and we just // effectively lost the last several digits). double fracPart = 0; // Absolute value of the power of 10 that we should multiply by (only // relevant for numbers in scientific notation). Has to be a signed integer, // because multiplication of signed by unsigned converts the unsigned to // signed, so if we plan to actually multiply by expSign... PRInt32 exponent = 0; // Sign of the exponent. PRInt32 expSign = 1; if (aToken.mHasSign) { NS_ASSERTION(c != '.', "How did that happen?"); c = Read(); } PRBool gotDot = (c == '.'); if (!gotDot) { // Parse the integer part of the mantisssa NS_ASSERTION(IsDigit(c), "Why did we get called?"); do { intPart = 10*intPart + CHAR_TO_DIGIT(c); c = Read(); // The IsDigit check will do the right thing even if Read() returns < 0 } while (IsDigit(c)); gotDot = (c == '.') && IsDigit(Peek()); } if (gotDot) { // Parse the fractional part of the mantissa. c = Read(); NS_ASSERTION(IsDigit(c), "How did we get here?"); // Power of ten by which we need to divide our next digit float divisor = 10; do { fracPart += CHAR_TO_DIGIT(c) / divisor; divisor *= 10; c = Read(); // The IsDigit check will do the right thing even if Read() returns < 0 } while (IsDigit(c)); } PRBool gotE = PR_FALSE; #ifdef MOZ_SVG if (IsSVGMode() && (c == 'e' || c == 'E')) { PRInt32 nextChar = Peek(); PRInt32 expSignChar = 0; if (nextChar == '-' || nextChar == '+') { expSignChar = Read(); nextChar = Peek(); } if (IsDigit(nextChar)) { gotE = PR_TRUE; if (expSignChar == '-') { expSign = -1; } c = Read(); NS_ASSERTION(IsDigit(c), "Peek() must have lied"); do { exponent = 10*exponent + CHAR_TO_DIGIT(c); c = Read(); // The IsDigit check will do the right thing even if Read() returns < 0 } while (IsDigit(c)); } else { if (expSignChar) { Pushback(expSignChar); } } } #endif nsCSSTokenType type = eCSSToken_Number; // Set mIntegerValid for all cases (except %, below) because we need // it for the "2n" in :nth-child(2n). aToken.mIntegerValid = PR_FALSE; // Time to reassemble our number. float value = float(sign * (intPart + fracPart)); if (gotE) { // pow(), not powf(), because at least wince doesn't have the latter. // And explicitly cast everything to doubles to avoid issues with // overloaded pow() on Windows. value *= pow(10.0, double(expSign * exponent)); } else if (!gotDot) { if (intPart > PR_INT32_MAX) { // Just clamp it. intPart = PR_INT32_MAX; } aToken.mInteger = PRInt32(sign * intPart); aToken.mIntegerValid = PR_TRUE; } nsString& ident = aToken.mIdent; ident.Truncate(); // Look at character that terminated the number if (c >= 0) { if (StartsIdent(c, Peek())) { if (!GatherIdent(c, ident)) { return PR_FALSE; } type = eCSSToken_Dimension; } else if ('%' == c) { type = eCSSToken_Percentage; value = value / 100.0f; aToken.mIntegerValid = PR_FALSE; } else { // Put back character that stopped numeric scan Pushback(c); } } aToken.mNumber = value; aToken.mType = type; return PR_TRUE; } PRBool nsCSSScanner::SkipCComment() { for (;;) { PRInt32 ch = Read(); if (ch < 0) break; if (ch == '*') { if (LookAhead('/')) { return PR_TRUE; } } } REPORT_UNEXPECTED_EOF(PECommentEOF); return PR_FALSE; } PRBool nsCSSScanner::ParseString(PRInt32 aStop, nsCSSToken& aToken) { aToken.mIdent.SetLength(0); aToken.mType = eCSSToken_String; aToken.mSymbol = PRUnichar(aStop); // remember how it's quoted for (;;) { // If nothing in pushback, first try to get as much as possible in one go if (!mPushbackCount && EnsureData()) { // See how much we can consume and append in one go PRUint32 n = mOffset; // Count number of characters that can be processed for (;n < mCount; ++n) { PRUnichar nextChar = mReadPointer[n]; if ((nextChar == aStop) || (nextChar == CSS_ESCAPE) || (nextChar == '\n') || (nextChar == '\r') || (nextChar == '\f')) { break; } #ifdef CSS_REPORT_PARSE_ERRORS if (nextChar == '\t') { mColNumber = ((mColNumber - 1 + TAB_STOP_WIDTH) / TAB_STOP_WIDTH) * TAB_STOP_WIDTH; } else { ++mColNumber; } #endif } // Add to the token what we have so far if (n > mOffset) { aToken.mIdent.Append(&mReadPointer[mOffset], n - mOffset); mOffset = n; } } PRInt32 ch = Read(); if (ch < 0 || ch == aStop) { break; } if (ch == '\n') { aToken.mType = eCSSToken_Error; #ifdef CSS_REPORT_PARSE_ERRORS ReportUnexpectedToken(aToken, "SEUnterminatedString"); #endif break; } if (ch == CSS_ESCAPE) { ParseAndAppendEscape(aToken.mIdent); } else { aToken.mIdent.Append(ch); } } return PR_TRUE; }