1 //===-- HostInfoLinux.cpp ---------------------------------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "lldb/Core/Log.h"
11 #include "lldb/Host/linux/HostInfoLinux.h"
12 
13 #include <limits.h>
14 #include <stdio.h>
15 #include <string.h>
16 #include <sys/utsname.h>
17 
18 #include <algorithm>
19 
20 using namespace lldb_private;
21 
22 namespace
23 {
24 struct HostInfoLinuxFields
25 {
26     HostInfoLinuxFields()
27         : m_os_major(0)
28         , m_os_minor(0)
29         , m_os_update(0)
30     {
31     }
32 
33     std::string m_distribution_id;
34     uint32_t m_os_major;
35     uint32_t m_os_minor;
36     uint32_t m_os_update;
37 };
38 
39 HostInfoLinuxFields *g_fields = nullptr;
40 }
41 
42 void
43 HostInfoLinux::Initialize()
44 {
45     HostInfoPosix::Initialize();
46 
47     g_fields = new HostInfoLinuxFields();
48 }
49 
50 uint32_t
51 HostInfoLinux::GetMaxThreadNameLength()
52 {
53     return 16;
54 }
55 
56 bool
57 HostInfoLinux::GetOSVersion(uint32_t &major, uint32_t &minor, uint32_t &update)
58 {
59     static bool is_initialized = false;
60     static bool success = false;
61 
62     if (!is_initialized)
63     {
64         is_initialized = true;
65         struct utsname un;
66 
67         if (uname(&un))
68             goto finished;
69 
70         int status = sscanf(un.release, "%u.%u.%u", &g_fields->m_os_major, &g_fields->m_os_minor, &g_fields->m_os_update);
71         if (status == 3)
72         {
73             success = true;
74             goto finished;
75         }
76 
77         // Some kernels omit the update version, so try looking for just "X.Y" and
78         // set update to 0.
79         g_fields->m_os_update = 0;
80         status = sscanf(un.release, "%u.%u", &g_fields->m_os_major, &g_fields->m_os_minor);
81         success = !!(status == 2);
82     }
83 
84 finished:
85     major = g_fields->m_os_major;
86     minor = g_fields->m_os_minor;
87     update = g_fields->m_os_update;
88     return success;
89 }
90 
91 llvm::StringRef
92 HostInfoLinux::GetDistributionId()
93 {
94     static bool is_initialized = false;
95     // Try to run 'lbs_release -i', and use that response
96     // for the distribution id.
97 
98     if (!is_initialized)
99     {
100         is_initialized = true;
101 
102         Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_HOST));
103         if (log)
104             log->Printf("attempting to determine Linux distribution...");
105 
106         // check if the lsb_release command exists at one of the
107         // following paths
108         const char *const exe_paths[] = {"/bin/lsb_release", "/usr/bin/lsb_release"};
109 
110         for (size_t exe_index = 0; exe_index < sizeof(exe_paths) / sizeof(exe_paths[0]); ++exe_index)
111         {
112             const char *const get_distribution_info_exe = exe_paths[exe_index];
113             if (access(get_distribution_info_exe, F_OK))
114             {
115                 // this exe doesn't exist, move on to next exe
116                 if (log)
117                     log->Printf("executable doesn't exist: %s", get_distribution_info_exe);
118                 continue;
119             }
120 
121             // execute the distribution-retrieval command, read output
122             std::string get_distribution_id_command(get_distribution_info_exe);
123             get_distribution_id_command += " -i";
124 
125             FILE *file = popen(get_distribution_id_command.c_str(), "r");
126             if (!file)
127             {
128                 if (log)
129                     log->Printf("failed to run command: \"%s\", cannot retrieve "
130                                 "platform information",
131                                 get_distribution_id_command.c_str());
132                 break;
133             }
134 
135             // retrieve the distribution id string.
136             char distribution_id[256] = {'\0'};
137             if (fgets(distribution_id, sizeof(distribution_id) - 1, file) != NULL)
138             {
139                 if (log)
140                     log->Printf("distribution id command returned \"%s\"", distribution_id);
141 
142                 const char *const distributor_id_key = "Distributor ID:\t";
143                 if (strstr(distribution_id, distributor_id_key))
144                 {
145                     // strip newlines
146                     std::string id_string(distribution_id + strlen(distributor_id_key));
147                     id_string.erase(std::remove(id_string.begin(), id_string.end(), '\n'), id_string.end());
148 
149                     // lower case it and convert whitespace to underscores
150                     std::transform(id_string.begin(), id_string.end(), id_string.begin(), [](char ch)
151                                    {
152                         return tolower(isspace(ch) ? '_' : ch);
153                     });
154 
155                     g_fields->m_distribution_id = id_string;
156                     if (log)
157                         log->Printf("distribution id set to \"%s\"", g_fields->m_distribution_id.c_str());
158                 }
159                 else
160                 {
161                     if (log)
162                         log->Printf("failed to find \"%s\" field in \"%s\"", distributor_id_key, distribution_id);
163                 }
164             }
165             else
166             {
167                 if (log)
168                     log->Printf("failed to retrieve distribution id, \"%s\" returned no"
169                                 " lines",
170                                 get_distribution_id_command.c_str());
171             }
172 
173             // clean up the file
174             pclose(file);
175         }
176     }
177 
178     return g_fields->m_distribution_id.c_str();
179 }
180 
181 FileSpec
182 HostInfoLinux::GetProgramFileSpec()
183 {
184     static FileSpec g_program_filespec;
185 
186     if (!g_program_filespec)
187     {
188         char exe_path[PATH_MAX];
189         ssize_t len = readlink("/proc/self/exe", exe_path, sizeof(exe_path) - 1);
190         if (len > 0)
191         {
192             exe_path[len] = 0;
193             g_program_filespec.SetFile(exe_path, false);
194         }
195     }
196 
197     return g_program_filespec;
198 }
199 
200 bool
201 HostInfoLinux::ComputeSystemPluginsDirectory(FileSpec &file_spec)
202 {
203     FileSpec temp_file("/usr/lib/lldb", true);
204     file_spec.GetDirectory().SetCString(temp_file.GetPath().c_str());
205     return true;
206 }
207 
208 bool
209 HostInfoLinux::ComputeUserPluginsDirectory(FileSpec &file_spec)
210 {
211     // XDG Base Directory Specification
212     // http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html
213     // If XDG_DATA_HOME exists, use that, otherwise use ~/.local/share/lldb.
214     const char *xdg_data_home = getenv("XDG_DATA_HOME");
215     if (xdg_data_home && xdg_data_home[0])
216     {
217         std::string user_plugin_dir(xdg_data_home);
218         user_plugin_dir += "/lldb";
219         file_spec.GetDirectory().SetCString(user_plugin_dir.c_str());
220     }
221     else
222         file_spec.GetDirectory().SetCString("~/.local/share/lldb");
223     return true;
224 }
225 
226 void
227 HostInfoLinux::ComputeHostArchitectureSupport(ArchSpec &arch_32, ArchSpec &arch_64)
228 {
229     HostInfoPosix::ComputeHostArchitectureSupport(arch_32, arch_64);
230 
231     const char *distribution_id = GetDistributionId().data();
232 
233     // On Linux, "unknown" in the vendor slot isn't what we want for the default
234     // triple.  It's probably an artifact of config.guess.
235     if (arch_32.IsValid())
236     {
237         arch_32.SetDistributionId(distribution_id);
238         if (arch_32.GetTriple().getVendor() == llvm::Triple::UnknownVendor)
239             arch_32.GetTriple().setVendorName("");
240     }
241     if (arch_64.IsValid())
242     {
243         arch_64.SetDistributionId(distribution_id);
244         if (arch_64.GetTriple().getVendor() == llvm::Triple::UnknownVendor)
245             arch_64.GetTriple().setVendorName("");
246     }
247 }
248