gecko-dev/dom/canvas/WebGLValidateStrings.cpp

193 строки
4.7 KiB
C++

/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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 <regex>
#include "WebGLTypes.h"
#include "nsPrintfCString.h"
namespace mozilla {
/* GLSL ES 3.00 p17:
- Comments are delimited by / * and * /, or by // and a newline.
- '//' style comments include the initial '//' marker and continue up to, but
not including, the terminating newline.
- '/ * ... * /' comments include both the start and end marker.
- The begin comment delimiters (/ * or //) are not recognized as comment
delimiters inside of a comment, hence comments cannot be nested.
- Comments are treated syntactically as a single space.
*/
std::string CommentsToSpaces(const std::string& src) {
constexpr auto flags =
std::regex::ECMAScript | std::regex::nosubs | std::regex::optimize;
static const auto RE_COMMENT_BEGIN = std::regex("/[*/]", flags);
static const auto RE_LINE_COMMENT_END = std::regex(R"([^\\]\n)", flags);
static const auto RE_BLOCK_COMMENT_END = std::regex(R"(\*/)", flags);
std::string ret;
ret.reserve(src.size());
// Replace all comments with block comments with the right number of newlines.
// Line positions may be off, but line numbers will be accurate, which is more
// important.
auto itr = src.begin();
const auto end = src.end();
std::smatch match;
while (std::regex_search(itr, end, match, RE_COMMENT_BEGIN)) {
MOZ_ASSERT(match.length() == 2);
const auto commentBegin = itr + match.position();
ret.append(itr, commentBegin);
itr = commentBegin + match.length();
const bool isBlockComment = (*(commentBegin + 1) == '*');
const auto* endRegex = &RE_LINE_COMMENT_END;
if (isBlockComment) {
endRegex = &RE_BLOCK_COMMENT_END;
}
if (isBlockComment) {
ret += "/*";
}
auto commentEnd = end;
if (!isBlockComment && itr != end && *itr == '\n') {
commentEnd = itr + 1; // '//\n'
} else if (std::regex_search(itr, end, match, *endRegex)) {
commentEnd = itr + match.position() + match.length();
} else {
return ret;
}
for (; itr != commentEnd; ++itr) {
const auto cur = *itr;
if (cur == '\n') {
ret += cur;
}
}
if (isBlockComment) {
ret += "*/";
}
}
ret.append(itr, end);
return ret;
}
////////////////////////////////////////////////////////////////////////////////
static constexpr bool IsValidGLSLChar(const char c) {
if (('a' <= c && c <= 'z') || ('A' <= c && c <= 'Z') ||
('0' <= c && c <= '9')) {
return true;
}
switch (c) {
case ' ':
case '\t':
case '\v':
case '\f':
case '\r':
case '\n':
case '_':
case '.':
case '+':
case '-':
case '/':
case '*':
case '%':
case '<':
case '>':
case '[':
case ']':
case '(':
case ')':
case '{':
case '}':
case '^':
case '|':
case '&':
case '~':
case '=':
case '!':
case ':':
case ';':
case ',':
case '?':
return true;
default:
return false;
}
}
static constexpr bool IsValidForPreprocOrGlsl(const char c) {
switch (c) {
case '#':
case '\\':
return true;
default:
return IsValidGLSLChar(c);
}
}
////
static constexpr char INVALID_GLSL_CHAR = '$';
std::string CrushGlslToAscii(const std::string& u8) {
static_assert(!IsValidForPreprocOrGlsl(INVALID_GLSL_CHAR));
auto ascii = u8;
for (auto& c : ascii) {
if (MOZ_UNLIKELY(!IsValidForPreprocOrGlsl(c))) {
c = INVALID_GLSL_CHAR;
}
}
return ascii;
}
Maybe<webgl::ErrorInfo> CheckGLSLVariableName(const bool webgl2,
const std::string& name) {
if (name.empty()) return {};
const uint32_t maxSize = webgl2 ? 1024 : 256;
if (name.size() > maxSize) {
const auto info = nsPrintfCString(
"Identifier is %zu characters long, exceeds the"
" maximum allowed length of %u characters.",
name.size(), maxSize);
return Some(webgl::ErrorInfo{LOCAL_GL_INVALID_VALUE, info.BeginReading()});
}
for (const auto cur : name) {
if (!IsValidGLSLChar(cur)) {
const auto info =
nsPrintfCString("String contains the illegal character 0x%x'.", cur);
return Some(
webgl::ErrorInfo{LOCAL_GL_INVALID_VALUE, info.BeginReading()});
}
}
if (name.find("webgl_") == 0 || name.find("_webgl_") == 0) {
return Some(webgl::ErrorInfo{
LOCAL_GL_INVALID_OPERATION,
"String matches reserved GLSL prefix pattern /_?webgl_/."});
}
return {};
}
} // namespace mozilla