clang/lib/Driver/Distro.cpp

   1 //===--- Distro.cpp - Linux distribution detection support ------*- 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-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "clang/Driver/Distro.h"
  10 #include "clang/Basic/LLVM.h"
  11 #include "llvm/ADT/SmallVector.h"
  12 #include "llvm/ADT/StringRef.h"
  13 #include "llvm/ADT/StringSwitch.h"
  14 #include "llvm/Support/ErrorOr.h"
  15 #include "llvm/Support/MemoryBuffer.h"
  16 #include "llvm/Support/Threading.h"
  17 #include "llvm/TargetParser/Host.h"
  18 #include "llvm/TargetParser/Triple.h"
  19
  20 using namespace clang::driver;
  21 using namespace clang;
  22
  23 static Distro::DistroType DetectOsRelease(llvm::vfs::FileSystem &VFS) {
  24   llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> File =
  25       VFS.getBufferForFile("/etc/os-release");
  26   if (!File)
  27     File = VFS.getBufferForFile("/usr/lib/os-release");
  28   if (!File)
  29     return Distro::UnknownDistro;
  30
  31   SmallVector<StringRef, 16> Lines;
  32   File.get()->getBuffer().split(Lines, "\n");
  33   Distro::DistroType Version = Distro::UnknownDistro;
  34
  35   // Obviously this can be improved a lot.
  36   for (StringRef Line : Lines)
  37     if (Version == Distro::UnknownDistro && Line.startswith("ID="))
  38       Version = llvm::StringSwitch<Distro::DistroType>(Line.substr(3))
  39                     .Case("alpine", Distro::AlpineLinux)
  40                     .Case("fedora", Distro::Fedora)
  41                     .Case("gentoo", Distro::Gentoo)
  42                     .Case("arch", Distro::ArchLinux)
  43                     // On SLES, /etc/os-release was introduced in SLES 11.
  44                     .Case("sles", Distro::OpenSUSE)
  45                     .Case("opensuse", Distro::OpenSUSE)
  46                     .Case("exherbo", Distro::Exherbo)
  47                     .Default(Distro::UnknownDistro);
  48   return Version;
  49 }
  50
  51 static Distro::DistroType DetectLsbRelease(llvm::vfs::FileSystem &VFS) {
  52   llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> File =
  53       VFS.getBufferForFile("/etc/lsb-release");
  54   if (!File)
  55     return Distro::UnknownDistro;
  56
  57   SmallVector<StringRef, 16> Lines;
  58   File.get()->getBuffer().split(Lines, "\n");
  59   Distro::DistroType Version = Distro::UnknownDistro;
  60
  61   for (StringRef Line : Lines)
  62     if (Version == Distro::UnknownDistro &&
  63         Line.startswith("DISTRIB_CODENAME="))
  64       Version = llvm::StringSwitch<Distro::DistroType>(Line.substr(17))
  65                     .Case("hardy", Distro::UbuntuHardy)
  66                     .Case("intrepid", Distro::UbuntuIntrepid)
  67                     .Case("jaunty", Distro::UbuntuJaunty)
  68                     .Case("karmic", Distro::UbuntuKarmic)
  69                     .Case("lucid", Distro::UbuntuLucid)
  70                     .Case("maverick", Distro::UbuntuMaverick)
  71                     .Case("natty", Distro::UbuntuNatty)
  72                     .Case("oneiric", Distro::UbuntuOneiric)
  73                     .Case("precise", Distro::UbuntuPrecise)
  74                     .Case("quantal", Distro::UbuntuQuantal)
  75                     .Case("raring", Distro::UbuntuRaring)
  76                     .Case("saucy", Distro::UbuntuSaucy)
  77                     .Case("trusty", Distro::UbuntuTrusty)
  78                     .Case("utopic", Distro::UbuntuUtopic)
  79                     .Case("vivid", Distro::UbuntuVivid)
  80                     .Case("wily", Distro::UbuntuWily)
  81                     .Case("xenial", Distro::UbuntuXenial)
  82                     .Case("yakkety", Distro::UbuntuYakkety)
  83                     .Case("zesty", Distro::UbuntuZesty)
  84                     .Case("artful", Distro::UbuntuArtful)
  85                     .Case("bionic", Distro::UbuntuBionic)
  86                     .Case("cosmic", Distro::UbuntuCosmic)
  87                     .Case("disco", Distro::UbuntuDisco)
  88                     .Case("eoan", Distro::UbuntuEoan)
  89                     .Case("focal", Distro::UbuntuFocal)
  90                     .Case("groovy", Distro::UbuntuGroovy)
  91                     .Case("hirsute", Distro::UbuntuHirsute)
  92                     .Case("impish", Distro::UbuntuImpish)
  93                     .Case("jammy", Distro::UbuntuJammy)
  94                     .Case("kinetic", Distro::UbuntuKinetic)
  95                     .Case("lunar", Distro::UbuntuLunar)
  96                     .Case("mantic", Distro::UbuntuMantic)
  97                     .Case("noble", Distro::UbuntuNoble)
  98                     .Default(Distro::UnknownDistro);
  99   return Version;
 100 }
 101
 102 static Distro::DistroType DetectDistro(llvm::vfs::FileSystem &VFS) {
 103   Distro::DistroType Version = Distro::UnknownDistro;
 104
 105   // Newer freedesktop.org's compilant systemd-based systems
 106   // should provide /etc/os-release or /usr/lib/os-release.
 107   Version = DetectOsRelease(VFS);
 108   if (Version != Distro::UnknownDistro)
 109     return Version;
 110
 111   // Older systems might provide /etc/lsb-release.
 112   Version = DetectLsbRelease(VFS);
 113   if (Version != Distro::UnknownDistro)
 114     return Version;
 115
 116   // Otherwise try some distro-specific quirks for Red Hat...
 117   llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> File =
 118       VFS.getBufferForFile("/etc/redhat-release");
 119
 120   if (File) {
 121     StringRef Data = File.get()->getBuffer();
 122     if (Data.startswith("Fedora release"))
 123       return Distro::Fedora;
 124     if (Data.startswith("Red Hat Enterprise Linux") ||
 125         Data.startswith("CentOS") || Data.startswith("Scientific Linux")) {
 126       if (Data.contains("release 7"))
 127         return Distro::RHEL7;
 128       else if (Data.contains("release 6"))
 129         return Distro::RHEL6;
 130       else if (Data.contains("release 5"))
 131         return Distro::RHEL5;
 132     }
 133     return Distro::UnknownDistro;
 134   }
 135
 136   // ...for Debian
 137   File = VFS.getBufferForFile("/etc/debian_version");
 138   if (File) {
 139     StringRef Data = File.get()->getBuffer();
 140     // Contents: < major.minor > or < codename/sid >
 141     int MajorVersion;
 142     if (!Data.split('.').first.getAsInteger(10, MajorVersion)) {
 143       switch (MajorVersion) {
 144       case 5:
 145         return Distro::DebianLenny;
 146       case 6:
 147         return Distro::DebianSqueeze;
 148       case 7:
 149         return Distro::DebianWheezy;
 150       case 8:
 151         return Distro::DebianJessie;
 152       case 9:
 153         return Distro::DebianStretch;
 154       case 10:
 155         return Distro::DebianBuster;
 156       case 11:
 157         return Distro::DebianBullseye;
 158       case 12:
 159         return Distro::DebianBookworm;
 160       case 13:
 161         return Distro::DebianTrixie;
 162       default:
 163         return Distro::UnknownDistro;
 164       }
 165     }
 166     return llvm::StringSwitch<Distro::DistroType>(Data.split("\n").first)
 167         .Case("squeeze/sid", Distro::DebianSqueeze)
 168         .Case("wheezy/sid", Distro::DebianWheezy)
 169         .Case("jessie/sid", Distro::DebianJessie)
 170         .Case("stretch/sid", Distro::DebianStretch)
 171         .Case("buster/sid", Distro::DebianBuster)
 172         .Case("bullseye/sid", Distro::DebianBullseye)
 173         .Case("bookworm/sid", Distro::DebianBookworm)
 174         .Case("trixie/sid", Distro::DebianTrixie)
 175         .Default(Distro::UnknownDistro);
 176   }
 177
 178   // ...for SUSE
 179   File = VFS.getBufferForFile("/etc/SuSE-release");
 180   if (File) {
 181     StringRef Data = File.get()->getBuffer();
 182     SmallVector<StringRef, 8> Lines;
 183     Data.split(Lines, "\n");
 184     for (const StringRef &Line : Lines) {
 185       if (!Line.trim().startswith("VERSION"))
 186         continue;
 187       std::pair<StringRef, StringRef> SplitLine = Line.split('=');
 188       // Old versions have split VERSION and PATCHLEVEL
 189       // Newer versions use VERSION = x.y
 190       std::pair<StringRef, StringRef> SplitVer =
 191           SplitLine.second.trim().split('.');
 192       int Version;
 193
 194       // OpenSUSE/SLES 10 and older are not supported and not compatible
 195       // with our rules, so just treat them as Distro::UnknownDistro.
 196       if (!SplitVer.first.getAsInteger(10, Version) && Version > 10)
 197         return Distro::OpenSUSE;
 198       return Distro::UnknownDistro;
 199     }
 200     return Distro::UnknownDistro;
 201   }
 202
 203   // ...and others.
 204   if (VFS.exists("/etc/gentoo-release"))
 205     return Distro::Gentoo;
 206
 207   return Distro::UnknownDistro;
 208 }
 209
 210 static Distro::DistroType GetDistro(llvm::vfs::FileSystem &VFS,
 211                                     const llvm::Triple &TargetOrHost) {
 212   // If we don't target Linux, no need to check the distro. This saves a few
 213   // OS calls.
 214   if (!TargetOrHost.isOSLinux())
 215     return Distro::UnknownDistro;
 216
 217   // True if we're backed by a real file system.
 218   const bool onRealFS = (llvm::vfs::getRealFileSystem() == &VFS);
 219
 220   // If the host is not running Linux, and we're backed by a real file
 221   // system, no need to check the distro. This is the case where someone
 222   // is cross-compiling from BSD or Windows to Linux, and it would be
 223   // meaningless to try to figure out the "distro" of the non-Linux host.
 224   llvm::Triple HostTriple(llvm::sys::getProcessTriple());
 225   if (!HostTriple.isOSLinux() && onRealFS)
 226     return Distro::UnknownDistro;
 227
 228   if (onRealFS) {
 229     // If we're backed by a real file system, perform
 230     // the detection only once and save the result.
 231     static Distro::DistroType LinuxDistro = DetectDistro(VFS);
 232     return LinuxDistro;
 233   }
 234   // This is mostly for passing tests which uses llvm::vfs::InMemoryFileSystem,
 235   // which is not "real".
 236   return DetectDistro(VFS);
 237 }
 238
 239 Distro::Distro(llvm::vfs::FileSystem &VFS, const llvm::Triple &TargetOrHost)
 240     : DistroVal(GetDistro(VFS, TargetOrHost)) {}