xref: /freebsd/contrib/llvm-project/clang/lib/Driver/Distro.cpp (revision 833a452e9f082a7982a31c21f0da437dbbe0a39d)
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 
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                     .Default(Distro::UnknownDistro);
94   return Version;
95 }
96 
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 
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 
228 Distro::Distro(llvm::vfs::FileSystem &VFS, const llvm::Triple &TargetOrHost)
229     : DistroVal(GetDistro(VFS, TargetOrHost)) {}
230