diff options
Diffstat (limited to 'dom/canvas/WebGLValidateStrings.cpp')
| -rw-r--r-- | dom/canvas/WebGLValidateStrings.cpp | 169 |
1 files changed, 169 insertions, 0 deletions
diff --git a/dom/canvas/WebGLValidateStrings.cpp b/dom/canvas/WebGLValidateStrings.cpp new file mode 100644 index 000000000..9df3fef70 --- /dev/null +++ b/dom/canvas/WebGLValidateStrings.cpp @@ -0,0 +1,169 @@ +/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ +/* 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 "WebGLValidateStrings.h" + +#include "nsString.h" +#include "WebGLContext.h" + +namespace mozilla { +// The following code was taken from the WebKit WebGL implementation, +// which can be found here: +// http://trac.webkit.org/browser/trunk/Source/WebCore/html/canvas/WebGLRenderingContext.cpp?rev=93625#L121 +// Note that some modifications were done to adapt it to Mozilla. +/****** BEGIN CODE TAKEN FROM WEBKIT ******/ +bool IsValidGLSLCharacter(char16_t c) +{ + // Printing characters are valid except " $ ` @ \ ' DEL. + if (c >= 32 && c <= 126 && + c != '"' && c != '$' && c != '`' && c != '@' && c != '\\' && c != '\'') + { + return true; + } + + // Horizontal tab, line feed, vertical tab, form feed, carriage return + // are also valid. + if (c >= 9 && c <= 13) { + return true; + } + + return false; +} + +void StripComments::process(char16_t c) +{ + if (isNewline(c)) { + // No matter what state we are in, pass through newlines + // so we preserve line numbers. + emit(c); + + if (m_parseState != InMultiLineComment) + m_parseState = BeginningOfLine; + + return; + } + + char16_t temp = 0; + switch (m_parseState) { + case BeginningOfLine: + // If it's an ASCII space. + if (c <= ' ' && (c == ' ' || (c <= 0xD && c >= 0x9))) { + emit(c); + break; + } + + if (c == '#') { + m_parseState = InPreprocessorDirective; + emit(c); + break; + } + + // Transition to normal state and re-handle character. + m_parseState = MiddleOfLine; + process(c); + break; + + case MiddleOfLine: + if (c == '/' && peek(temp)) { + if (temp == '/') { + m_parseState = InSingleLineComment; + emit(' '); + advance(); + break; + } + + if (temp == '*') { + m_parseState = InMultiLineComment; + // Emit the comment start in case the user has + // an unclosed comment and we want to later + // signal an error. + emit('/'); + emit('*'); + advance(); + break; + } + } + + emit(c); + break; + + case InPreprocessorDirective: + // No matter what the character is, just pass it + // through. Do not parse comments in this state. This + // might not be the right thing to do long term, but it + // should handle the #error preprocessor directive. + emit(c); + break; + + case InSingleLineComment: + // The newline code at the top of this function takes care + // of resetting our state when we get out of the + // single-line comment. Swallow all other characters. + break; + + case InMultiLineComment: + if (c == '*' && peek(temp) && temp == '/') { + emit('*'); + emit('/'); + m_parseState = MiddleOfLine; + advance(); + break; + } + + // Swallow all other characters. Unclear whether we may + // want or need to just emit a space per character to try + // to preserve column numbers for debugging purposes. + break; + } +} + +/****** END CODE TAKEN FROM WEBKIT ******/ + +bool +ValidateGLSLString(const nsAString& string, WebGLContext* webgl, const char* funcName) +{ + for (size_t i = 0; i < string.Length(); ++i) { + if (!IsValidGLSLCharacter(string.CharAt(i))) { + webgl->ErrorInvalidValue("%s: String contains the illegal character '%d'", + funcName, string.CharAt(i)); + return false; + } + } + + return true; +} + +bool +ValidateGLSLVariableName(const nsAString& name, WebGLContext* webgl, const char* funcName) +{ + if (name.IsEmpty()) + return false; + + const uint32_t maxSize = webgl->IsWebGL2() ? 1024 : 256; + if (name.Length() > maxSize) { + webgl->ErrorInvalidValue("%s: Identifier is %d characters long, exceeds the" + " maximum allowed length of %d characters.", + funcName, name.Length(), maxSize); + return false; + } + + if (!ValidateGLSLString(name, webgl, funcName)) + return false; + + nsString prefix1 = NS_LITERAL_STRING("webgl_"); + nsString prefix2 = NS_LITERAL_STRING("_webgl_"); + + if (Substring(name, 0, prefix1.Length()).Equals(prefix1) || + Substring(name, 0, prefix2.Length()).Equals(prefix2)) + { + webgl->ErrorInvalidOperation("%s: String contains a reserved GLSL prefix.", + funcName); + return false; + } + + return true; +} + +} // namespace mozilla |