180 lines · cpp
1//===- split-file.cpp - Input splitting utility ---------------------------===//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// Split input into multipe parts separated by regex '^(.|//)--- ' and extract10// the specified part.11//12//===----------------------------------------------------------------------===//13 14#include "llvm/ADT/DenseMap.h"15#include "llvm/ADT/StringExtras.h"16#include "llvm/ADT/StringRef.h"17#include "llvm/Support/CommandLine.h"18#include "llvm/Support/FileOutputBuffer.h"19#include "llvm/Support/FileSystem.h"20#include "llvm/Support/LineIterator.h"21#include "llvm/Support/MemoryBuffer.h"22#include "llvm/Support/Path.h"23#include "llvm/Support/ToolOutputFile.h"24#include "llvm/Support/WithColor.h"25#include <string>26#include <system_error>27 28using namespace llvm;29 30static cl::OptionCategory cat("split-file Options");31 32static cl::opt<std::string> input(cl::Positional, cl::desc("filename"),33 cl::cat(cat));34 35static cl::opt<std::string> output(cl::Positional, cl::desc("directory"),36 cl::value_desc("directory"), cl::cat(cat));37 38static cl::opt<bool> leadingLines("leading-lines",39 cl::desc("Preserve line numbers"),40 cl::cat(cat));41 42static cl::opt<bool> noLeadingLines("no-leading-lines",43 cl::desc("Don't preserve line numbers (default)"),44 cl::cat(cat));45 46static StringRef toolName;47static int errorCount;48 49[[noreturn]] static void fatal(StringRef filename, const Twine &message) {50 if (filename.empty())51 WithColor::error(errs(), toolName) << message << '\n';52 else53 WithColor::error(errs(), toolName) << filename << ": " << message << '\n';54 exit(1);55}56 57static void error(StringRef filename, int64_t line, const Twine &message) {58 ++errorCount;59 errs() << filename << ':' << line << ": ";60 WithColor::error(errs()) << message << '\n';61}62 63namespace {64struct Part {65 const char *begin = nullptr;66 const char *end = nullptr;67 int64_t leadingLines = 0;68};69} // namespace70 71static int handle(MemoryBuffer &inputBuf, StringRef input) {72 DenseMap<StringRef, Part> partToBegin;73 StringRef lastPart, separator;74 StringRef EOL = inputBuf.getBuffer().detectEOL();75 for (line_iterator i(inputBuf, /*SkipBlanks=*/false, '\0'); !i.is_at_eof();) {76 const int64_t lineNo = i.line_number();77 const StringRef line = *i++;78 const size_t markerLen = line.starts_with("//") ? 6 : 5;79 if (!(line.size() >= markerLen &&80 line.substr(markerLen - 4).starts_with("--- ")))81 continue;82 separator = line.substr(0, markerLen);83 const StringRef partName = line.substr(markerLen);84 if (partName.empty()) {85 error(input, lineNo, "empty part name");86 continue;87 }88 if (isSpace(partName.front()) || isSpace(partName.back())) {89 error(input, lineNo, "part name cannot have leading or trailing space");90 continue;91 }92 93 auto res = partToBegin.try_emplace(partName);94 if (!res.second) {95 error(input, lineNo,96 "'" + separator + partName + "' occurs more than once");97 continue;98 }99 if (!lastPart.empty())100 partToBegin[lastPart].end = line.data();101 Part &cur = res.first->second;102 if (!i.is_at_eof())103 cur.begin = i->data();104 // If --leading-lines is specified, numEmptyLines is 0. Append newlines so105 // that the extracted part preserves line numbers.106 cur.leadingLines = leadingLines ? i.line_number() - 1 : 0;107 108 lastPart = partName;109 }110 if (lastPart.empty())111 fatal(input, "no part separator was found");112 if (errorCount)113 return 1;114 partToBegin[lastPart].end = inputBuf.getBufferEnd();115 116 std::vector<std::unique_ptr<ToolOutputFile>> outputFiles;117 SmallString<256> partPath;118 for (auto &keyValue : partToBegin) {119 partPath.clear();120 sys::path::append(partPath, output, keyValue.first);121 std::error_code ec =122 sys::fs::create_directories(sys::path::parent_path(partPath));123 if (ec)124 fatal(input, ec.message());125 auto f = std::make_unique<ToolOutputFile>(partPath.str(), ec,126 llvm::sys::fs::OF_Text);127 if (!f)128 fatal(input, ec.message());129 130 Part &part = keyValue.second;131 for (int64_t i = 0; i != part.leadingLines; ++i)132 (*f).os() << EOL;133 if (part.begin)134 (*f).os().write(part.begin, part.end - part.begin);135 outputFiles.push_back(std::move(f));136 }137 138 for (std::unique_ptr<ToolOutputFile> &outputFile : outputFiles)139 outputFile->keep();140 return 0;141}142 143int main(int argc, const char **argv) {144 toolName = sys::path::stem(argv[0]);145 cl::HideUnrelatedOptions({&cat});146 cl::ParseCommandLineOptions(147 argc, argv,148 "Split input into multiple parts separated by regex '^(.|//)--- ' and "149 "extract the part specified by '^(.|//)--- <part>'\n",150 nullptr,151 /*VFS=*/nullptr,152 /*EnvVar=*/nullptr,153 /*LongOptionsUseDoubleDash=*/true);154 155 if (input.empty())156 fatal("", "input filename is not specified");157 if (output.empty())158 fatal("", "output directory is not specified");159 ErrorOr<std::unique_ptr<MemoryBuffer>> bufferOrErr =160 MemoryBuffer::getFileOrSTDIN(input, /*IsText=*/true);161 if (std::error_code ec = bufferOrErr.getError())162 fatal(input, ec.message());163 164 // Delete output if it is a file or an empty directory, so that we can create165 // a directory.166 sys::fs::file_status status;167 if (std::error_code ec = sys::fs::status(output, status))168 if (ec.value() != static_cast<int>(std::errc::no_such_file_or_directory))169 fatal(output, ec.message());170 if (status.type() != sys::fs::file_type::file_not_found &&171 status.type() != sys::fs::file_type::directory_file &&172 status.type() != sys::fs::file_type::regular_file)173 fatal(output, "output cannot be a special file");174 if (std::error_code ec = sys::fs::remove(output, /*IgnoreNonExisting=*/true))175 if (ec.value() != static_cast<int>(std::errc::directory_not_empty) &&176 ec.value() != static_cast<int>(std::errc::file_exists))177 fatal(output, ec.message());178 return handle(**bufferOrErr, input);179}180