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| author | 2020-08-03 15:06:44 +0000 | |
|---|---|---|
| committer | 2020-08-03 15:06:44 +0000 | |
| commit | b64793999546ed8adebaeebd9d8345d18db8927d (patch) | |
| tree | 4357c27b561d73b0e089727c6ed659f2ceff5f47 /gnu/llvm/lib/Support/TarWriter.cpp | |
| parent | Add support for UTF-8 DISPLAY-HINTs with octet length. For now only (diff) | |
| download | wireguard-openbsd-b64793999546ed8adebaeebd9d8345d18db8927d.tar.xz wireguard-openbsd-b64793999546ed8adebaeebd9d8345d18db8927d.zip | |
Remove LLVM 8.0.1 files.
Diffstat (limited to 'gnu/llvm/lib/Support/TarWriter.cpp')
| -rw-r--r-- | gnu/llvm/lib/Support/TarWriter.cpp | 201 |
1 files changed, 0 insertions, 201 deletions
diff --git a/gnu/llvm/lib/Support/TarWriter.cpp b/gnu/llvm/lib/Support/TarWriter.cpp deleted file mode 100644 index 5b4d554befe..00000000000 --- a/gnu/llvm/lib/Support/TarWriter.cpp +++ /dev/null @@ -1,201 +0,0 @@ -//===-- TarWriter.cpp - Tar archive file creator --------------------------===// -// -// The LLVM Compiler Infrastructure -// -// This file is distributed under the University of Illinois Open Source -// License. See LICENSE.TXT for details. -// -//===----------------------------------------------------------------------===// -// -// TarWriter class provides a feature to create a tar archive file. -// -// I put emphasis on simplicity over comprehensiveness when implementing this -// class because we don't need a full-fledged archive file generator in LLVM -// at the moment. -// -// The filename field in the Unix V7 tar header is 100 bytes. Longer filenames -// are stored using the PAX extension. The PAX header is standardized in -// POSIX.1-2001. -// -// The struct definition of UstarHeader is copied from -// https://www.freebsd.org/cgi/man.cgi?query=tar&sektion=5 -// -//===----------------------------------------------------------------------===// - -#include "llvm/Support/TarWriter.h" -#include "llvm/ADT/StringRef.h" -#include "llvm/Support/FileSystem.h" -#include "llvm/Support/MathExtras.h" -#include "llvm/Support/Path.h" - -using namespace llvm; - -// Each file in an archive must be aligned to this block size. -static const int BlockSize = 512; - -struct UstarHeader { - char Name[100]; - char Mode[8]; - char Uid[8]; - char Gid[8]; - char Size[12]; - char Mtime[12]; - char Checksum[8]; - char TypeFlag; - char Linkname[100]; - char Magic[6]; - char Version[2]; - char Uname[32]; - char Gname[32]; - char DevMajor[8]; - char DevMinor[8]; - char Prefix[155]; - char Pad[12]; -}; -static_assert(sizeof(UstarHeader) == BlockSize, "invalid Ustar header"); - -static UstarHeader makeUstarHeader() { - UstarHeader Hdr = {}; - memcpy(Hdr.Magic, "ustar", 5); // Ustar magic - memcpy(Hdr.Version, "00", 2); // Ustar version - return Hdr; -} - -// A PAX attribute is in the form of "<length> <key>=<value>\n" -// where <length> is the length of the entire string including -// the length field itself. An example string is this. -// -// 25 ctime=1084839148.1212\n -// -// This function create such string. -static std::string formatPax(StringRef Key, StringRef Val) { - int Len = Key.size() + Val.size() + 3; // +3 for " ", "=" and "\n" - - // We need to compute total size twice because appending - // a length field could change total size by one. - int Total = Len + Twine(Len).str().size(); - Total = Len + Twine(Total).str().size(); - return (Twine(Total) + " " + Key + "=" + Val + "\n").str(); -} - -// Headers in tar files must be aligned to 512 byte boundaries. -// This function forwards the current file position to the next boundary. -static void pad(raw_fd_ostream &OS) { - uint64_t Pos = OS.tell(); - OS.seek(alignTo(Pos, BlockSize)); -} - -// Computes a checksum for a tar header. -static void computeChecksum(UstarHeader &Hdr) { - // Before computing a checksum, checksum field must be - // filled with space characters. - memset(Hdr.Checksum, ' ', sizeof(Hdr.Checksum)); - - // Compute a checksum and set it to the checksum field. - unsigned Chksum = 0; - for (size_t I = 0; I < sizeof(Hdr); ++I) - Chksum += reinterpret_cast<uint8_t *>(&Hdr)[I]; - snprintf(Hdr.Checksum, sizeof(Hdr.Checksum), "%06o", Chksum); -} - -// Create a tar header and write it to a given output stream. -static void writePaxHeader(raw_fd_ostream &OS, StringRef Path) { - // A PAX header consists of a 512-byte header followed - // by key-value strings. First, create key-value strings. - std::string PaxAttr = formatPax("path", Path); - - // Create a 512-byte header. - UstarHeader Hdr = makeUstarHeader(); - snprintf(Hdr.Size, sizeof(Hdr.Size), "%011zo", PaxAttr.size()); - Hdr.TypeFlag = 'x'; // PAX magic - computeChecksum(Hdr); - - // Write them down. - OS << StringRef(reinterpret_cast<char *>(&Hdr), sizeof(Hdr)); - OS << PaxAttr; - pad(OS); -} - -// Path fits in a Ustar header if -// -// - Path is less than 100 characters long, or -// - Path is in the form of "<prefix>/<name>" where <prefix> is less -// than or equal to 155 characters long and <name> is less than 100 -// characters long. Both <prefix> and <name> can contain extra '/'. -// -// If Path fits in a Ustar header, updates Prefix and Name and returns true. -// Otherwise, returns false. -static bool splitUstar(StringRef Path, StringRef &Prefix, StringRef &Name) { - if (Path.size() < sizeof(UstarHeader::Name)) { - Prefix = ""; - Name = Path; - return true; - } - - size_t Sep = Path.rfind('/', sizeof(UstarHeader::Prefix) + 1); - if (Sep == StringRef::npos) - return false; - if (Path.size() - Sep - 1 >= sizeof(UstarHeader::Name)) - return false; - - Prefix = Path.substr(0, Sep); - Name = Path.substr(Sep + 1); - return true; -} - -// The PAX header is an extended format, so a PAX header needs -// to be followed by a "real" header. -static void writeUstarHeader(raw_fd_ostream &OS, StringRef Prefix, - StringRef Name, size_t Size) { - UstarHeader Hdr = makeUstarHeader(); - memcpy(Hdr.Name, Name.data(), Name.size()); - memcpy(Hdr.Mode, "0000664", 8); - snprintf(Hdr.Size, sizeof(Hdr.Size), "%011zo", Size); - memcpy(Hdr.Prefix, Prefix.data(), Prefix.size()); - computeChecksum(Hdr); - OS << StringRef(reinterpret_cast<char *>(&Hdr), sizeof(Hdr)); -} - -// Creates a TarWriter instance and returns it. -Expected<std::unique_ptr<TarWriter>> TarWriter::create(StringRef OutputPath, - StringRef BaseDir) { - using namespace sys::fs; - int FD; - if (std::error_code EC = - openFileForWrite(OutputPath, FD, CD_CreateAlways, OF_None)) - return make_error<StringError>("cannot open " + OutputPath, EC); - return std::unique_ptr<TarWriter>(new TarWriter(FD, BaseDir)); -} - -TarWriter::TarWriter(int FD, StringRef BaseDir) - : OS(FD, /*shouldClose=*/true, /*unbuffered=*/false), BaseDir(BaseDir) {} - -// Append a given file to an archive. -void TarWriter::append(StringRef Path, StringRef Data) { - // Write Path and Data. - std::string Fullpath = BaseDir + "/" + sys::path::convert_to_slash(Path); - - // We do not want to include the same file more than once. - if (!Files.insert(Fullpath).second) - return; - - StringRef Prefix; - StringRef Name; - if (splitUstar(Fullpath, Prefix, Name)) { - writeUstarHeader(OS, Prefix, Name, Data.size()); - } else { - writePaxHeader(OS, Fullpath); - writeUstarHeader(OS, "", "", Data.size()); - } - - OS << Data; - pad(OS); - - // POSIX requires tar archives end with two null blocks. - // Here, we write the terminator and then seek back, so that - // the file being output is terminated correctly at any moment. - uint64_t Pos = OS.tell(); - OS << std::string(BlockSize * 2, '\0'); - OS.seek(Pos); - OS.flush(); -} |
