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/ADT/Triple.h"
15 #include "llvm/Support/ErrorOr.h"
16 #include "llvm/Support/Host.h"
17 #include "llvm/Support/MemoryBuffer.h"
18 #include "llvm/Support/Threading.h"
19
20 using namespace clang::driver;
21 using namespace clang;
22
DetectOsRelease(llvm::vfs::FileSystem & VFS)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
DetectLsbRelease(llvm::vfs::FileSystem & VFS)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 .Default(Distro::UnknownDistro);
94 return Version;
95 }
96
DetectDistro(llvm::vfs::FileSystem & VFS)97 static Distro::DistroType DetectDistro(llvm::vfs::FileSystem &VFS) {
98 Distro::DistroType Version = Distro::UnknownDistro;
99
100 // Newer freedesktop.org's compilant systemd-based systems
101 // should provide /etc/os-release or /usr/lib/os-release.
102 Version = DetectOsRelease(VFS);
103 if (Version != Distro::UnknownDistro)
104 return Version;
105
106 // Older systems might provide /etc/lsb-release.
107 Version = DetectLsbRelease(VFS);
108 if (Version != Distro::UnknownDistro)
109 return Version;
110
111 // Otherwise try some distro-specific quirks for RedHat...
112 llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> File =
113 VFS.getBufferForFile("/etc/redhat-release");
114
115 if (File) {
116 StringRef Data = File.get()->getBuffer();
117 if (Data.startswith("Fedora release"))
118 return Distro::Fedora;
119 if (Data.startswith("Red Hat Enterprise Linux") ||
120 Data.startswith("CentOS") || Data.startswith("Scientific Linux")) {
121 if (Data.find("release 7") != StringRef::npos)
122 return Distro::RHEL7;
123 else if (Data.find("release 6") != StringRef::npos)
124 return Distro::RHEL6;
125 else if (Data.find("release 5") != StringRef::npos)
126 return Distro::RHEL5;
127 }
128 return Distro::UnknownDistro;
129 }
130
131 // ...for Debian
132 File = VFS.getBufferForFile("/etc/debian_version");
133 if (File) {
134 StringRef Data = File.get()->getBuffer();
135 // Contents: < major.minor > or < codename/sid >
136 int MajorVersion;
137 if (!Data.split('.').first.getAsInteger(10, MajorVersion)) {
138 switch (MajorVersion) {
139 case 5:
140 return Distro::DebianLenny;
141 case 6:
142 return Distro::DebianSqueeze;
143 case 7:
144 return Distro::DebianWheezy;
145 case 8:
146 return Distro::DebianJessie;
147 case 9:
148 return Distro::DebianStretch;
149 case 10:
150 return Distro::DebianBuster;
151 case 11:
152 return Distro::DebianBullseye;
153 default:
154 return Distro::UnknownDistro;
155 }
156 }
157 return llvm::StringSwitch<Distro::DistroType>(Data.split("\n").first)
158 .Case("squeeze/sid", Distro::DebianSqueeze)
159 .Case("wheezy/sid", Distro::DebianWheezy)
160 .Case("jessie/sid", Distro::DebianJessie)
161 .Case("stretch/sid", Distro::DebianStretch)
162 .Case("buster/sid", Distro::DebianBuster)
163 .Case("bullseye/sid", Distro::DebianBullseye)
164 .Default(Distro::UnknownDistro);
165 }
166
167 // ...for SUSE
168 File = VFS.getBufferForFile("/etc/SuSE-release");
169 if (File) {
170 StringRef Data = File.get()->getBuffer();
171 SmallVector<StringRef, 8> Lines;
172 Data.split(Lines, "\n");
173 for (const StringRef &Line : Lines) {
174 if (!Line.trim().startswith("VERSION"))
175 continue;
176 std::pair<StringRef, StringRef> SplitLine = Line.split('=');
177 // Old versions have split VERSION and PATCHLEVEL
178 // Newer versions use VERSION = x.y
179 std::pair<StringRef, StringRef> SplitVer =
180 SplitLine.second.trim().split('.');
181 int Version;
182
183 // OpenSUSE/SLES 10 and older are not supported and not compatible
184 // with our rules, so just treat them as Distro::UnknownDistro.
185 if (!SplitVer.first.getAsInteger(10, Version) && Version > 10)
186 return Distro::OpenSUSE;
187 return Distro::UnknownDistro;
188 }
189 return Distro::UnknownDistro;
190 }
191
192 // ...and others.
193 if (VFS.exists("/etc/gentoo-release"))
194 return Distro::Gentoo;
195
196 return Distro::UnknownDistro;
197 }
198
GetDistro(llvm::vfs::FileSystem & VFS,const llvm::Triple & TargetOrHost)199 static Distro::DistroType GetDistro(llvm::vfs::FileSystem &VFS,
200 const llvm::Triple &TargetOrHost) {
201 // If we don't target Linux, no need to check the distro. This saves a few
202 // OS calls.
203 if (!TargetOrHost.isOSLinux())
204 return Distro::UnknownDistro;
205
206 // True if we're backed by a real file system.
207 const bool onRealFS = (llvm::vfs::getRealFileSystem() == &VFS);
208
209 // If the host is not running Linux, and we're backed by a real file
210 // system, no need to check the distro. This is the case where someone
211 // is cross-compiling from BSD or Windows to Linux, and it would be
212 // meaningless to try to figure out the "distro" of the non-Linux host.
213 llvm::Triple HostTriple(llvm::sys::getProcessTriple());
214 if (!HostTriple.isOSLinux() && onRealFS)
215 return Distro::UnknownDistro;
216
217 if (onRealFS) {
218 // If we're backed by a real file system, perform
219 // the detection only once and save the result.
220 static Distro::DistroType LinuxDistro = DetectDistro(VFS);
221 return LinuxDistro;
222 }
223 // This is mostly for passing tests which uses llvm::vfs::InMemoryFileSystem,
224 // which is not "real".
225 return DetectDistro(VFS);
226 }
227
Distro(llvm::vfs::FileSystem & VFS,const llvm::Triple & TargetOrHost)228 Distro::Distro(llvm::vfs::FileSystem &VFS, const llvm::Triple &TargetOrHost)
229 : DistroVal(GetDistro(VFS, TargetOrHost)) {}
230