1//===-- HostInfoLinux.cpp -------------------------------------------------===//
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 "lldb/Host/linux/HostInfoLinux.h"
10#include "lldb/Host/Config.h"
11#include "lldb/Host/FileSystem.h"
12#include "lldb/Utility/LLDBLog.h"
13#include "lldb/Utility/Log.h"
14
15#include "llvm/Support/Threading.h"
16
17#include <climits>
18#include <cstdio>
19#include <cstring>
20#include <sys/utsname.h>
21#include <unistd.h>
22
23#include <algorithm>
24#include <mutex>
25#include <optional>
26
27using namespace lldb_private;
28
29namespace {
30struct HostInfoLinuxFields {
31 llvm::once_flag m_distribution_once_flag;
32 std::string m_distribution_id;
33 llvm::once_flag m_os_version_once_flag;
34 llvm::VersionTuple m_os_version;
35};
36} // namespace
37
38static HostInfoLinuxFields *g_fields = nullptr;
39
40void HostInfoLinux::Initialize(SharedLibraryDirectoryHelper *helper) {
41 HostInfoPosix::Initialize(helper);
42
43 g_fields = new HostInfoLinuxFields();
44}
45
46void HostInfoLinux::Terminate() {
47 assert(g_fields && "Missing call to Initialize?");
48 delete g_fields;
49 g_fields = nullptr;
50 HostInfoBase::Terminate();
51}
52
53llvm::VersionTuple HostInfoLinux::GetOSVersion() {
54 assert(g_fields && "Missing call to Initialize?");
55 llvm::call_once(flag&: g_fields->m_os_version_once_flag, F: []() {
56 struct utsname un;
57 if (uname(name: &un) != 0)
58 return;
59
60 llvm::StringRef release = un.release;
61 // The kernel release string can include a lot of stuff (e.g.
62 // 4.9.0-6-amd64). We're only interested in the numbered prefix.
63 release = release.substr(Start: 0, N: release.find_first_not_of(Chars: "0123456789."));
64 g_fields->m_os_version.tryParse(string: release);
65 });
66
67 return g_fields->m_os_version;
68}
69
70std::optional<std::string> HostInfoLinux::GetOSBuildString() {
71 struct utsname un;
72 ::memset(s: &un, c: 0, n: sizeof(utsname));
73
74 if (uname(name: &un) < 0)
75 return std::nullopt;
76
77 return std::string(un.release);
78}
79
80llvm::StringRef HostInfoLinux::GetDistributionId() {
81 assert(g_fields && "Missing call to Initialize?");
82 // Try to run 'lbs_release -i', and use that response for the distribution
83 // id.
84 llvm::call_once(flag&: g_fields->m_distribution_once_flag, F: []() {
85 Log *log = GetLog(mask: LLDBLog::Host);
86 LLDB_LOGF(log, "attempting to determine Linux distribution...");
87
88 // check if the lsb_release command exists at one of the following paths
89 const char *const exe_paths[] = {"/bin/lsb_release",
90 "/usr/bin/lsb_release"};
91
92 for (size_t exe_index = 0;
93 exe_index < sizeof(exe_paths) / sizeof(exe_paths[0]); ++exe_index) {
94 const char *const get_distribution_info_exe = exe_paths[exe_index];
95 if (access(name: get_distribution_info_exe, F_OK)) {
96 // this exe doesn't exist, move on to next exe
97 LLDB_LOGF(log, "executable doesn't exist: %s",
98 get_distribution_info_exe);
99 continue;
100 }
101
102 // execute the distribution-retrieval command, read output
103 std::string get_distribution_id_command(get_distribution_info_exe);
104 get_distribution_id_command += " -i";
105
106 FILE *file = popen(command: get_distribution_id_command.c_str(), modes: "r");
107 if (!file) {
108 LLDB_LOGF(log,
109 "failed to run command: \"%s\", cannot retrieve "
110 "platform information",
111 get_distribution_id_command.c_str());
112 break;
113 }
114
115 // retrieve the distribution id string.
116 char distribution_id[256] = {'\0'};
117 if (fgets(s: distribution_id, n: sizeof(distribution_id) - 1, stream: file) !=
118 nullptr) {
119 LLDB_LOGF(log, "distribution id command returned \"%s\"",
120 distribution_id);
121
122 const char *const distributor_id_key = "Distributor ID:\t";
123 if (strstr(haystack: distribution_id, needle: distributor_id_key)) {
124 // strip newlines
125 std::string id_string(distribution_id + strlen(s: distributor_id_key));
126 llvm::erase(C&: id_string, V: '\n');
127
128 // lower case it and convert whitespace to underscores
129 std::transform(
130 first: id_string.begin(), last: id_string.end(), result: id_string.begin(),
131 unary_op: [](char ch) { return tolower(c: isspace(ch) ? '_' : ch); });
132
133 g_fields->m_distribution_id = id_string;
134 LLDB_LOGF(log, "distribution id set to \"%s\"",
135 g_fields->m_distribution_id.c_str());
136 } else {
137 LLDB_LOGF(log, "failed to find \"%s\" field in \"%s\"",
138 distributor_id_key, distribution_id);
139 }
140 } else {
141 LLDB_LOGF(log,
142 "failed to retrieve distribution id, \"%s\" returned no"
143 " lines",
144 get_distribution_id_command.c_str());
145 }
146
147 // clean up the file
148 pclose(stream: file);
149 }
150 });
151
152 return g_fields->m_distribution_id;
153}
154
155FileSpec HostInfoLinux::GetProgramFileSpec() {
156 static FileSpec g_program_filespec;
157
158 if (!g_program_filespec) {
159 char exe_path[PATH_MAX];
160 ssize_t len = readlink(path: "/proc/self/exe", buf: exe_path, len: sizeof(exe_path) - 1);
161 if (len > 0) {
162 exe_path[len] = 0;
163 g_program_filespec.SetFile(path: exe_path, style: FileSpec::Style::native);
164 }
165 }
166
167 return g_program_filespec;
168}
169
170bool HostInfoLinux::ComputeSupportExeDirectory(FileSpec &file_spec) {
171 if (HostInfoPosix::ComputeSupportExeDirectory(file_spec) &&
172 file_spec.IsAbsolute() && FileSystem::Instance().Exists(file_spec))
173 return true;
174 file_spec.SetDirectory(GetProgramFileSpec().GetDirectory());
175 return !file_spec.GetDirectory().IsEmpty();
176}
177
178bool HostInfoLinux::ComputeSystemPluginsDirectory(FileSpec &file_spec) {
179 FileSpec temp_file("/usr/" LLDB_INSTALL_LIBDIR_BASENAME "/lldb/plugins");
180 FileSystem::Instance().Resolve(file_spec&: temp_file);
181 file_spec.SetDirectory(temp_file.GetPath());
182 return true;
183}
184
185bool HostInfoLinux::ComputeUserPluginsDirectory(FileSpec &file_spec) {
186 // XDG Base Directory Specification
187 // http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html If
188 // XDG_DATA_HOME exists, use that, otherwise use ~/.local/share/lldb.
189 const char *xdg_data_home = getenv(name: "XDG_DATA_HOME");
190 if (xdg_data_home && xdg_data_home[0]) {
191 std::string user_plugin_dir(xdg_data_home);
192 user_plugin_dir += "/lldb";
193 file_spec.SetDirectory(user_plugin_dir.c_str());
194 } else
195 file_spec.SetDirectory("~/.local/share/lldb");
196 return true;
197}
198
199void HostInfoLinux::ComputeHostArchitectureSupport(ArchSpec &arch_32,
200 ArchSpec &arch_64) {
201 HostInfoPosix::ComputeHostArchitectureSupport(arch_32, arch_64);
202
203 // On Linux, "unknown" in the vendor slot isn't what we want for the default
204 // triple. It's probably an artifact of config.guess.
205 if (arch_32.IsValid()) {
206 if (arch_32.GetTriple().getVendor() == llvm::Triple::UnknownVendor)
207 arch_32.GetTriple().setVendorName(llvm::StringRef());
208 }
209 if (arch_64.IsValid()) {
210 if (arch_64.GetTriple().getVendor() == llvm::Triple::UnknownVendor)
211 arch_64.GetTriple().setVendorName(llvm::StringRef());
212 }
213}
214

source code of lldb/source/Host/linux/HostInfoLinux.cpp