source/Host/linux/HostInfoLinux.cpp - llvm-project/lldb - Git at Google

 //===-- HostInfoLinux.cpp -------------------------------------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//

 #include "lldb/Host/linux/HostInfoLinux.h"
 #include "lldb/Host/Config.h"
 #include "lldb/Host/FileSystem.h"
 #include "lldb/Utility/Log.h"

 #include "llvm/Support/Threading.h"

 #include <limits.h>
 #include <stdio.h>
 #include <string.h>
 #include <sys/utsname.h>
 #include <unistd.h>

 #include <algorithm>
 #include <mutex>

 using namespace lldb_private;

 namespace {
 struct HostInfoLinuxFields {
   std::string m_distribution_id;
   llvm::VersionTuple m_os_version;
 };

 HostInfoLinuxFields *g_fields = nullptr;
 }

 void HostInfoLinux::Initialize(SharedLibraryDirectoryHelper *helper) {
   HostInfoPosix::Initialize(helper);

   g_fields = new HostInfoLinuxFields();
 }

 llvm::VersionTuple HostInfoLinux::GetOSVersion() {
   static llvm::once_flag g_once_flag;
   llvm::call_once(g_once_flag, []() {
     struct utsname un;
     if (uname(&un) != 0)
       return;

     llvm::StringRef release = un.release;
     // The kernel release string can include a lot of stuff (e.g.
     // 4.9.0-6-amd64). We're only interested in the numbered prefix.
     release = release.substr(0, release.find_first_not_of("0123456789."));
     g_fields->m_os_version.tryParse(release);
   });

   return g_fields->m_os_version;
 }

 bool HostInfoLinux::GetOSBuildString(std::string &s) {
   struct utsname un;
   ::memset(&un, 0, sizeof(utsname));
   s.clear();

   if (uname(&un) < 0)
     return false;

   s.assign(un.release);
   return true;
 }

 bool HostInfoLinux::GetOSKernelDescription(std::string &s) {
   struct utsname un;

   ::memset(&un, 0, sizeof(utsname));
   s.clear();

   if (uname(&un) < 0)
     return false;

   s.assign(un.version);
   return true;
 }

 llvm::StringRef HostInfoLinux::GetDistributionId() {
   // Try to run 'lbs_release -i', and use that response for the distribution
   // id.
   static llvm::once_flag g_once_flag;
   llvm::call_once(g_once_flag, []() {

     Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_HOST));
     LLDB_LOGF(log, "attempting to determine Linux distribution...");

     // check if the lsb_release command exists at one of the following paths
     const char *const exe_paths[] = {"/bin/lsb_release",
                                      "/usr/bin/lsb_release"};

     for (size_t exe_index = 0;
          exe_index < sizeof(exe_paths) / sizeof(exe_paths[0]); ++exe_index) {
       const char *const get_distribution_info_exe = exe_paths[exe_index];
       if (access(get_distribution_info_exe, F_OK)) {
         // this exe doesn't exist, move on to next exe
         LLDB_LOGF(log, "executable doesn't exist: %s",
                   get_distribution_info_exe);
         continue;
       }

       // execute the distribution-retrieval command, read output
       std::string get_distribution_id_command(get_distribution_info_exe);
       get_distribution_id_command += " -i";

       FILE *file = popen(get_distribution_id_command.c_str(), "r");
       if (!file) {
         LLDB_LOGF(log,
                   "failed to run command: \"%s\", cannot retrieve "
                   "platform information",
                   get_distribution_id_command.c_str());
         break;
       }

       // retrieve the distribution id string.
       char distribution_id[256] = {'\0'};
       if (fgets(distribution_id, sizeof(distribution_id) - 1, file) !=
           nullptr) {
         LLDB_LOGF(log, "distribution id command returned \"%s\"",
                   distribution_id);

         const char *const distributor_id_key = "Distributor ID:\t";
         if (strstr(distribution_id, distributor_id_key)) {
           // strip newlines
           std::string id_string(distribution_id + strlen(distributor_id_key));
           id_string.erase(std::remove(id_string.begin(), id_string.end(), '\n'),
                           id_string.end());

           // lower case it and convert whitespace to underscores
           std::transform(
               id_string.begin(), id_string.end(), id_string.begin(),
               [](char ch) { return tolower(isspace(ch) ? '_' : ch); });

           g_fields->m_distribution_id = id_string;
           LLDB_LOGF(log, "distribution id set to \"%s\"",
                     g_fields->m_distribution_id.c_str());
         } else {
           LLDB_LOGF(log, "failed to find \"%s\" field in \"%s\"",
                     distributor_id_key, distribution_id);
         }
       } else {
         LLDB_LOGF(log,
                   "failed to retrieve distribution id, \"%s\" returned no"
                   " lines",
                   get_distribution_id_command.c_str());
       }

       // clean up the file
       pclose(file);
     }
   });

   return g_fields->m_distribution_id;
 }

 FileSpec HostInfoLinux::GetProgramFileSpec() {
   static FileSpec g_program_filespec;

   if (!g_program_filespec) {
     char exe_path[PATH_MAX];
     ssize_t len = readlink("/proc/self/exe", exe_path, sizeof(exe_path) - 1);
     if (len > 0) {
       exe_path[len] = 0;
       g_program_filespec.SetFile(exe_path, FileSpec::Style::native);
     }
   }

   return g_program_filespec;
 }

 bool HostInfoLinux::ComputeSupportExeDirectory(FileSpec &file_spec) {
   if (HostInfoPosix::ComputeSupportExeDirectory(file_spec) &&
       file_spec.IsAbsolute() && FileSystem::Instance().Exists(file_spec))
     return true;
   file_spec.GetDirectory() = GetProgramFileSpec().GetDirectory();
   return !file_spec.GetDirectory().IsEmpty();
 }

 bool HostInfoLinux::ComputeSystemPluginsDirectory(FileSpec &file_spec) {
   FileSpec temp_file("/usr/lib" LLDB_LIBDIR_SUFFIX "/lldb/plugins");
   FileSystem::Instance().Resolve(temp_file);
   file_spec.GetDirectory().SetCString(temp_file.GetPath().c_str());
   return true;
 }

 bool HostInfoLinux::ComputeUserPluginsDirectory(FileSpec &file_spec) {
   // XDG Base Directory Specification
   // http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html If
   // XDG_DATA_HOME exists, use that, otherwise use ~/.local/share/lldb.
   const char *xdg_data_home = getenv("XDG_DATA_HOME");
   if (xdg_data_home && xdg_data_home[0]) {
     std::string user_plugin_dir(xdg_data_home);
     user_plugin_dir += "/lldb";
     file_spec.GetDirectory().SetCString(user_plugin_dir.c_str());
   } else
     file_spec.GetDirectory().SetCString("~/.local/share/lldb");
   return true;
 }

 void HostInfoLinux::ComputeHostArchitectureSupport(ArchSpec &arch_32,
                                                    ArchSpec &arch_64) {
   HostInfoPosix::ComputeHostArchitectureSupport(arch_32, arch_64);

   const char *distribution_id = GetDistributionId().data();

   // On Linux, "unknown" in the vendor slot isn't what we want for the default
   // triple.  It's probably an artifact of config.guess.
   if (arch_32.IsValid()) {
     arch_32.SetDistributionId(distribution_id);
     if (arch_32.GetTriple().getVendor() == llvm::Triple::UnknownVendor)
       arch_32.GetTriple().setVendorName(llvm::StringRef());
   }
   if (arch_64.IsValid()) {
     arch_64.SetDistributionId(distribution_id);
     if (arch_64.GetTriple().getVendor() == llvm::Triple::UnknownVendor)
       arch_64.GetTriple().setVendorName(llvm::StringRef());
   }
 }
	//===-- HostInfoLinux.cpp -------------------------------------------------===//
	//
	// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
	// See https://llvm.org/LICENSE.txt for license information.
	// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
	//
	//===----------------------------------------------------------------------===//

	#include "lldb/Host/linux/HostInfoLinux.h"
	#include "lldb/Host/Config.h"
	#include "lldb/Host/FileSystem.h"
	#include "lldb/Utility/Log.h"

	#include "llvm/Support/Threading.h"

	#include <limits.h>
	#include <stdio.h>
	#include <string.h>
	#include <sys/utsname.h>
	#include <unistd.h>

	#include <algorithm>
	#include <mutex>

	using namespace lldb_private;

	namespace {
	struct HostInfoLinuxFields {
	std::string m_distribution_id;
	llvm::VersionTuple m_os_version;
	};

	HostInfoLinuxFields *g_fields = nullptr;
	}

	void HostInfoLinux::Initialize(SharedLibraryDirectoryHelper *helper) {
	HostInfoPosix::Initialize(helper);

	g_fields = new HostInfoLinuxFields();
	}

	llvm::VersionTuple HostInfoLinux::GetOSVersion() {
	static llvm::once_flag g_once_flag;
	llvm::call_once(g_once_flag, []() {
	struct utsname un;
	if (uname(&un) != 0)
	return;

	llvm::StringRef release = un.release;
	// The kernel release string can include a lot of stuff (e.g.
	// 4.9.0-6-amd64). We're only interested in the numbered prefix.
	release = release.substr(0, release.find_first_not_of("0123456789."));
	g_fields->m_os_version.tryParse(release);
	});

	return g_fields->m_os_version;
	}

	bool HostInfoLinux::GetOSBuildString(std::string &s) {
	struct utsname un;
	::memset(&un, 0, sizeof(utsname));
	s.clear();

	if (uname(&un) < 0)
	return false;

	s.assign(un.release);
	return true;
	}

	bool HostInfoLinux::GetOSKernelDescription(std::string &s) {
	struct utsname un;

	::memset(&un, 0, sizeof(utsname));
	s.clear();

	if (uname(&un) < 0)
	return false;

	s.assign(un.version);
	return true;
	}

	llvm::StringRef HostInfoLinux::GetDistributionId() {
	// Try to run 'lbs_release -i', and use that response for the distribution
	// id.
	static llvm::once_flag g_once_flag;
	llvm::call_once(g_once_flag, []() {

	Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_HOST));
	LLDB_LOGF(log, "attempting to determine Linux distribution...");

	// check if the lsb_release command exists at one of the following paths
	const char *const exe_paths[] = {"/bin/lsb_release",
	"/usr/bin/lsb_release"};

	for (size_t exe_index = 0;
	exe_index < sizeof(exe_paths) / sizeof(exe_paths[0]); ++exe_index) {
	const char *const get_distribution_info_exe = exe_paths[exe_index];
	if (access(get_distribution_info_exe, F_OK)) {
	// this exe doesn't exist, move on to next exe
	LLDB_LOGF(log, "executable doesn't exist: %s",
	get_distribution_info_exe);
	continue;
	}

	// execute the distribution-retrieval command, read output
	std::string get_distribution_id_command(get_distribution_info_exe);
	get_distribution_id_command += " -i";

	FILE *file = popen(get_distribution_id_command.c_str(), "r");
	if (!file) {
	LLDB_LOGF(log,
	"failed to run command: \"%s\", cannot retrieve "
	"platform information",
	get_distribution_id_command.c_str());
	break;
	}

	// retrieve the distribution id string.
	char distribution_id[256] = {'\0'};
	if (fgets(distribution_id, sizeof(distribution_id) - 1, file) !=
	nullptr) {
	LLDB_LOGF(log, "distribution id command returned \"%s\"",
	distribution_id);

	const char *const distributor_id_key = "Distributor ID:\t";
	if (strstr(distribution_id, distributor_id_key)) {
	// strip newlines
	std::string id_string(distribution_id + strlen(distributor_id_key));
	id_string.erase(std::remove(id_string.begin(), id_string.end(), '\n'),
	id_string.end());

	// lower case it and convert whitespace to underscores
	std::transform(
	id_string.begin(), id_string.end(), id_string.begin(),
	[](char ch) { return tolower(isspace(ch) ? '_' : ch); });

	g_fields->m_distribution_id = id_string;
	LLDB_LOGF(log, "distribution id set to \"%s\"",
	g_fields->m_distribution_id.c_str());
	} else {
	LLDB_LOGF(log, "failed to find \"%s\" field in \"%s\"",
	distributor_id_key, distribution_id);
	}
	} else {
	LLDB_LOGF(log,
	"failed to retrieve distribution id, \"%s\" returned no"
	" lines",
	get_distribution_id_command.c_str());
	}

	// clean up the file
	pclose(file);
	}
	});

	return g_fields->m_distribution_id;
	}

	FileSpec HostInfoLinux::GetProgramFileSpec() {
	static FileSpec g_program_filespec;

	if (!g_program_filespec) {
	char exe_path[PATH_MAX];
	ssize_t len = readlink("/proc/self/exe", exe_path, sizeof(exe_path) - 1);
	if (len > 0) {
	exe_path[len] = 0;
	g_program_filespec.SetFile(exe_path, FileSpec::Style::native);
	}
	}

	return g_program_filespec;
	}

	bool HostInfoLinux::ComputeSupportExeDirectory(FileSpec &file_spec) {
	if (HostInfoPosix::ComputeSupportExeDirectory(file_spec) &&
	file_spec.IsAbsolute() && FileSystem::Instance().Exists(file_spec))
	return true;
	file_spec.GetDirectory() = GetProgramFileSpec().GetDirectory();
	return !file_spec.GetDirectory().IsEmpty();
	}

	bool HostInfoLinux::ComputeSystemPluginsDirectory(FileSpec &file_spec) {
	FileSpec temp_file("/usr/lib" LLDB_LIBDIR_SUFFIX "/lldb/plugins");
	FileSystem::Instance().Resolve(temp_file);
	file_spec.GetDirectory().SetCString(temp_file.GetPath().c_str());
	return true;
	}

	bool HostInfoLinux::ComputeUserPluginsDirectory(FileSpec &file_spec) {
	// XDG Base Directory Specification
	// http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html If
	// XDG_DATA_HOME exists, use that, otherwise use ~/.local/share/lldb.
	const char *xdg_data_home = getenv("XDG_DATA_HOME");
	if (xdg_data_home && xdg_data_home[0]) {
	std::string user_plugin_dir(xdg_data_home);
	user_plugin_dir += "/lldb";
	file_spec.GetDirectory().SetCString(user_plugin_dir.c_str());
	} else
	file_spec.GetDirectory().SetCString("~/.local/share/lldb");
	return true;
	}

	void HostInfoLinux::ComputeHostArchitectureSupport(ArchSpec &arch_32,
	ArchSpec &arch_64) {
	HostInfoPosix::ComputeHostArchitectureSupport(arch_32, arch_64);

	const char *distribution_id = GetDistributionId().data();

	// On Linux, "unknown" in the vendor slot isn't what we want for the default
	// triple. It's probably an artifact of config.guess.
	if (arch_32.IsValid()) {
	arch_32.SetDistributionId(distribution_id);
	if (arch_32.GetTriple().getVendor() == llvm::Triple::UnknownVendor)
	arch_32.GetTriple().setVendorName(llvm::StringRef());
	}
	if (arch_64.IsValid()) {
	arch_64.SetDistributionId(distribution_id);
	if (arch_64.GetTriple().getVendor() == llvm::Triple::UnknownVendor)
	arch_64.GetTriple().setVendorName(llvm::StringRef());
	}
	}