112 lines · cpp
1//===-- ResourceScriptCppFilter.cpp ----------------------------*- C++ -*-===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===---------------------------------------------------------------------===//8//9// This file implements an interface defined in ResourceScriptCppFilter.h.10//11//===---------------------------------------------------------------------===//12 13#include "ResourceScriptCppFilter.h"14#include "llvm/ADT/StringExtras.h"15 16#include <vector>17 18using namespace llvm;19 20namespace {21 22class Filter {23public:24 explicit Filter(StringRef Input) : Data(Input), DataLength(Input.size()) {}25 26 std::string run();27 28private:29 // Parse the line, returning whether the line should be included in30 // the output.31 bool parseLine(StringRef Line);32 33 bool streamEof() const;34 35 StringRef Data;36 size_t DataLength;37 38 size_t Pos = 0;39 bool Outputting = true;40};41 42std::string Filter::run() {43 std::vector<StringRef> Output;44 45 while (!streamEof() && Pos != StringRef::npos) {46 size_t LineStart = Pos;47 Pos = Data.find_first_of("\r\n", Pos);48 Pos = Data.find_first_not_of("\r\n", Pos);49 StringRef Line = Data.take_front(Pos).drop_front(LineStart);50 51 if (parseLine(Line))52 Output.push_back(Line);53 }54 55 return llvm::join(Output, "");56}57 58bool Filter::parseLine(StringRef Line) {59 Line = Line.ltrim();60 61 if (!Line.consume_front("#")) {62 // A normal content line, filtered according to the current mode.63 return Outputting;64 }65 66 // Found a preprocessing directive line. From here on, we always return67 // false since the preprocessing directives should be filtered out.68 69 Line.consume_front("line");70 if (!Line.starts_with(" "))71 return false; // Not a line directive (pragma etc).72 73 // #line 123 "path/file.h"74 // # 123 "path/file.h" 175 76 Line =77 Line.ltrim(); // There could be multiple spaces after the #line directive78 79 size_t N;80 if (Line.consumeInteger(10, N)) // Returns true to signify an error81 return false;82 83 Line = Line.ltrim();84 85 if (!Line.consume_front("\""))86 return false; // Malformed line, no quote found.87 88 // Split the string at the last quote (in case the path name had89 // escaped quotes as well).90 Line = Line.rsplit('"').first;91 92 StringRef Ext = Line.rsplit('.').second;93 94 if (Ext.equals_insensitive("h") || Ext.equals_insensitive("c")) {95 Outputting = false;96 } else {97 Outputting = true;98 }99 100 return false;101}102 103bool Filter::streamEof() const { return Pos == DataLength; }104 105} // anonymous namespace106 107namespace llvm {108 109std::string filterCppOutput(StringRef Input) { return Filter(Input).run(); }110 111} // namespace llvm112