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};
34} // namespace
35
36static HostInfoLinuxFields *g_fields = nullptr;
37
38void HostInfoLinux::Initialize(SharedLibraryDirectoryHelper *helper) {
39 HostInfoPosix::Initialize(helper);
40
41 g_fields = new HostInfoLinuxFields();
42}
43
44void HostInfoLinux::Terminate() {
45 assert(g_fields && "Missing call to Initialize?");
46 delete g_fields;
47 g_fields = nullptr;
48 HostInfoBase::Terminate();
49}
50
51llvm::StringRef HostInfoLinux::GetDistributionId() {
52 assert(g_fields && "Missing call to Initialize?");
53 // Try to run 'lbs_release -i', and use that response for the distribution
54 // id.
55 llvm::call_once(flag&: g_fields->m_distribution_once_flag, F: []() {
56 Log *log = GetLog(mask: LLDBLog::Host);
57 LLDB_LOGF(log, "attempting to determine Linux distribution...");
58
59 // check if the lsb_release command exists at one of the following paths
60 const char *const exe_paths[] = {"/bin/lsb_release",
61 "/usr/bin/lsb_release"};
62
63 for (size_t exe_index = 0;
64 exe_index < sizeof(exe_paths) / sizeof(exe_paths[0]); ++exe_index) {
65 const char *const get_distribution_info_exe = exe_paths[exe_index];
66 if (access(name: get_distribution_info_exe, F_OK)) {
67 // this exe doesn't exist, move on to next exe
68 LLDB_LOGF(log, "executable doesn't exist: %s",
69 get_distribution_info_exe);
70 continue;
71 }
72
73 // execute the distribution-retrieval command, read output
74 std::string get_distribution_id_command(get_distribution_info_exe);
75 get_distribution_id_command += " -i";
76
77 FILE *file = popen(command: get_distribution_id_command.c_str(), modes: "r");
78 if (!file) {
79 LLDB_LOGF(log,
80 "failed to run command: \"%s\", cannot retrieve "
81 "platform information",
82 get_distribution_id_command.c_str());
83 break;
84 }
85
86 // retrieve the distribution id string.
87 char distribution_id[256] = {'\0'};
88 if (fgets(s: distribution_id, n: sizeof(distribution_id) - 1, stream: file) !=
89 nullptr) {
90 LLDB_LOGF(log, "distribution id command returned \"%s\"",
91 distribution_id);
92
93 const char *const distributor_id_key = "Distributor ID:\t";
94 if (strstr(haystack: distribution_id, needle: distributor_id_key)) {
95 // strip newlines
96 std::string id_string(distribution_id + strlen(s: distributor_id_key));
97 llvm::erase(C&: id_string, V: '\n');
98
99 // lower case it and convert whitespace to underscores
100 std::transform(
101 first: id_string.begin(), last: id_string.end(), result: id_string.begin(),
102 unary_op: [](char ch) { return tolower(c: isspace(ch) ? '_' : ch); });
103
104 g_fields->m_distribution_id = id_string;
105 LLDB_LOGF(log, "distribution id set to \"%s\"",
106 g_fields->m_distribution_id.c_str());
107 } else {
108 LLDB_LOGF(log, "failed to find \"%s\" field in \"%s\"",
109 distributor_id_key, distribution_id);
110 }
111 } else {
112 LLDB_LOGF(log,
113 "failed to retrieve distribution id, \"%s\" returned no"
114 " lines",
115 get_distribution_id_command.c_str());
116 }
117
118 // clean up the file
119 pclose(stream: file);
120 }
121 });
122
123 return g_fields->m_distribution_id;
124}
125
126FileSpec HostInfoLinux::GetProgramFileSpec() {
127 static FileSpec g_program_filespec;
128
129 if (!g_program_filespec) {
130 char exe_path[PATH_MAX];
131 ssize_t len = readlink(path: "/proc/self/exe", buf: exe_path, len: sizeof(exe_path) - 1);
132 if (len > 0) {
133 exe_path[len] = 0;
134 g_program_filespec.SetFile(path: exe_path, style: FileSpec::Style::native);
135 }
136 }
137
138 return g_program_filespec;
139}
140
141void HostInfoLinux::ComputeHostArchitectureSupport(ArchSpec &arch_32,
142 ArchSpec &arch_64) {
143 HostInfoPosix::ComputeHostArchitectureSupport(arch_32, arch_64);
144
145 // On Linux, "unknown" in the vendor slot isn't what we want for the default
146 // triple. It's probably an artifact of config.guess.
147 if (arch_32.IsValid()) {
148 if (arch_32.GetTriple().getVendor() == llvm::Triple::UnknownVendor)
149 arch_32.GetTriple().setVendorName(llvm::StringRef());
150 }
151 if (arch_64.IsValid()) {
152 if (arch_64.GetTriple().getVendor() == llvm::Triple::UnknownVendor)
153 arch_64.GetTriple().setVendorName(llvm::StringRef());
154 }
155}
156

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