1 //===-- PlatformLinux.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 "PlatformLinux.h"
10 #include "lldb/Host/Config.h"
11
12 #include <stdio.h>
13 #if LLDB_ENABLE_POSIX
14 #include <sys/utsname.h>
15 #endif
16
17 #include "lldb/Core/Debugger.h"
18 #include "lldb/Core/PluginManager.h"
19 #include "lldb/Host/HostInfo.h"
20 #include "lldb/Target/Process.h"
21 #include "lldb/Target/Target.h"
22 #include "lldb/Utility/FileSpec.h"
23 #include "lldb/Utility/Log.h"
24 #include "lldb/Utility/State.h"
25 #include "lldb/Utility/Status.h"
26 #include "lldb/Utility/StreamString.h"
27
28 // Define these constants from Linux mman.h for use when targeting remote linux
29 // systems even when host has different values.
30 #define MAP_PRIVATE 2
31 #define MAP_ANON 0x20
32
33 using namespace lldb;
34 using namespace lldb_private;
35 using namespace lldb_private::platform_linux;
36
37 LLDB_PLUGIN_DEFINE(PlatformLinux)
38
39 static uint32_t g_initialize_count = 0;
40
41
CreateInstance(bool force,const ArchSpec * arch)42 PlatformSP PlatformLinux::CreateInstance(bool force, const ArchSpec *arch) {
43 Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_PLATFORM));
44 LLDB_LOG(log, "force = {0}, arch=({1}, {2})", force,
45 arch ? arch->GetArchitectureName() : "<null>",
46 arch ? arch->GetTriple().getTriple() : "<null>");
47
48 bool create = force;
49 if (!create && arch && arch->IsValid()) {
50 const llvm::Triple &triple = arch->GetTriple();
51 switch (triple.getOS()) {
52 case llvm::Triple::Linux:
53 create = true;
54 break;
55
56 #if defined(__linux__)
57 // Only accept "unknown" for the OS if the host is linux and it "unknown"
58 // wasn't specified (it was just returned because it was NOT specified)
59 case llvm::Triple::OSType::UnknownOS:
60 create = !arch->TripleOSWasSpecified();
61 break;
62 #endif
63 default:
64 break;
65 }
66 }
67
68 LLDB_LOG(log, "create = {0}", create);
69 if (create) {
70 return PlatformSP(new PlatformLinux(false));
71 }
72 return PlatformSP();
73 }
74
GetPluginNameStatic(bool is_host)75 ConstString PlatformLinux::GetPluginNameStatic(bool is_host) {
76 if (is_host) {
77 static ConstString g_host_name(Platform::GetHostPlatformName());
78 return g_host_name;
79 } else {
80 static ConstString g_remote_name("remote-linux");
81 return g_remote_name;
82 }
83 }
84
GetPluginDescriptionStatic(bool is_host)85 const char *PlatformLinux::GetPluginDescriptionStatic(bool is_host) {
86 if (is_host)
87 return "Local Linux user platform plug-in.";
88 else
89 return "Remote Linux user platform plug-in.";
90 }
91
GetPluginName()92 ConstString PlatformLinux::GetPluginName() {
93 return GetPluginNameStatic(IsHost());
94 }
95
Initialize()96 void PlatformLinux::Initialize() {
97 PlatformPOSIX::Initialize();
98
99 if (g_initialize_count++ == 0) {
100 #if defined(__linux__) && !defined(__ANDROID__)
101 PlatformSP default_platform_sp(new PlatformLinux(true));
102 default_platform_sp->SetSystemArchitecture(HostInfo::GetArchitecture());
103 Platform::SetHostPlatform(default_platform_sp);
104 #endif
105 PluginManager::RegisterPlugin(
106 PlatformLinux::GetPluginNameStatic(false),
107 PlatformLinux::GetPluginDescriptionStatic(false),
108 PlatformLinux::CreateInstance, nullptr);
109 }
110 }
111
Terminate()112 void PlatformLinux::Terminate() {
113 if (g_initialize_count > 0) {
114 if (--g_initialize_count == 0) {
115 PluginManager::UnregisterPlugin(PlatformLinux::CreateInstance);
116 }
117 }
118
119 PlatformPOSIX::Terminate();
120 }
121
122 /// Default Constructor
PlatformLinux(bool is_host)123 PlatformLinux::PlatformLinux(bool is_host)
124 : PlatformPOSIX(is_host) // This is the local host platform
125 {}
126
GetSupportedArchitectureAtIndex(uint32_t idx,ArchSpec & arch)127 bool PlatformLinux::GetSupportedArchitectureAtIndex(uint32_t idx,
128 ArchSpec &arch) {
129 if (IsHost()) {
130 ArchSpec hostArch = HostInfo::GetArchitecture(HostInfo::eArchKindDefault);
131 if (hostArch.GetTriple().isOSLinux()) {
132 if (idx == 0) {
133 arch = hostArch;
134 return arch.IsValid();
135 } else if (idx == 1) {
136 // If the default host architecture is 64-bit, look for a 32-bit
137 // variant
138 if (hostArch.IsValid() && hostArch.GetTriple().isArch64Bit()) {
139 arch = HostInfo::GetArchitecture(HostInfo::eArchKind32);
140 return arch.IsValid();
141 }
142 }
143 }
144 } else {
145 if (m_remote_platform_sp)
146 return m_remote_platform_sp->GetSupportedArchitectureAtIndex(idx, arch);
147
148 llvm::Triple triple;
149 // Set the OS to linux
150 triple.setOS(llvm::Triple::Linux);
151 // Set the architecture
152 switch (idx) {
153 case 0:
154 triple.setArchName("x86_64");
155 break;
156 case 1:
157 triple.setArchName("i386");
158 break;
159 case 2:
160 triple.setArchName("arm");
161 break;
162 case 3:
163 triple.setArchName("aarch64");
164 break;
165 case 4:
166 triple.setArchName("mips64");
167 break;
168 case 5:
169 triple.setArchName("hexagon");
170 break;
171 case 6:
172 triple.setArchName("mips");
173 break;
174 case 7:
175 triple.setArchName("mips64el");
176 break;
177 case 8:
178 triple.setArchName("mipsel");
179 break;
180 case 9:
181 triple.setArchName("s390x");
182 break;
183 default:
184 return false;
185 }
186 // Leave the vendor as "llvm::Triple:UnknownVendor" and don't specify the
187 // vendor by calling triple.SetVendorName("unknown") so that it is a
188 // "unspecified unknown". This means when someone calls
189 // triple.GetVendorName() it will return an empty string which indicates
190 // that the vendor can be set when two architectures are merged
191
192 // Now set the triple into "arch" and return true
193 arch.SetTriple(triple);
194 return true;
195 }
196 return false;
197 }
198
GetStatus(Stream & strm)199 void PlatformLinux::GetStatus(Stream &strm) {
200 Platform::GetStatus(strm);
201
202 #if LLDB_ENABLE_POSIX
203 // Display local kernel information only when we are running in host mode.
204 // Otherwise, we would end up printing non-Linux information (when running on
205 // Mac OS for example).
206 if (IsHost()) {
207 struct utsname un;
208
209 if (uname(&un))
210 return;
211
212 strm.Printf(" Kernel: %s\n", un.sysname);
213 strm.Printf(" Release: %s\n", un.release);
214 strm.Printf(" Version: %s\n", un.version);
215 }
216 #endif
217 }
218
219 uint32_t
GetResumeCountForLaunchInfo(ProcessLaunchInfo & launch_info)220 PlatformLinux::GetResumeCountForLaunchInfo(ProcessLaunchInfo &launch_info) {
221 uint32_t resume_count = 0;
222
223 // Always resume past the initial stop when we use eLaunchFlagDebug
224 if (launch_info.GetFlags().Test(eLaunchFlagDebug)) {
225 // Resume past the stop for the final exec into the true inferior.
226 ++resume_count;
227 }
228
229 // If we're not launching a shell, we're done.
230 const FileSpec &shell = launch_info.GetShell();
231 if (!shell)
232 return resume_count;
233
234 std::string shell_string = shell.GetPath();
235 // We're in a shell, so for sure we have to resume past the shell exec.
236 ++resume_count;
237
238 // Figure out what shell we're planning on using.
239 const char *shell_name = strrchr(shell_string.c_str(), '/');
240 if (shell_name == nullptr)
241 shell_name = shell_string.c_str();
242 else
243 shell_name++;
244
245 if (strcmp(shell_name, "csh") == 0 || strcmp(shell_name, "tcsh") == 0 ||
246 strcmp(shell_name, "zsh") == 0 || strcmp(shell_name, "sh") == 0) {
247 // These shells seem to re-exec themselves. Add another resume.
248 ++resume_count;
249 }
250
251 return resume_count;
252 }
253
CanDebugProcess()254 bool PlatformLinux::CanDebugProcess() {
255 if (IsHost()) {
256 return true;
257 } else {
258 // If we're connected, we can debug.
259 return IsConnected();
260 }
261 }
262
CalculateTrapHandlerSymbolNames()263 void PlatformLinux::CalculateTrapHandlerSymbolNames() {
264 m_trap_handlers.push_back(ConstString("_sigtramp"));
265 m_trap_handlers.push_back(ConstString("__kernel_rt_sigreturn"));
266 m_trap_handlers.push_back(ConstString("__restore_rt"));
267 }
268
GetMmapArgumentList(const ArchSpec & arch,addr_t addr,addr_t length,unsigned prot,unsigned flags,addr_t fd,addr_t offset)269 MmapArgList PlatformLinux::GetMmapArgumentList(const ArchSpec &arch,
270 addr_t addr, addr_t length,
271 unsigned prot, unsigned flags,
272 addr_t fd, addr_t offset) {
273 uint64_t flags_platform = 0;
274 uint64_t map_anon = arch.IsMIPS() ? 0x800 : MAP_ANON;
275
276 if (flags & eMmapFlagsPrivate)
277 flags_platform |= MAP_PRIVATE;
278 if (flags & eMmapFlagsAnon)
279 flags_platform |= map_anon;
280
281 MmapArgList args({addr, length, prot, flags_platform, fd, offset});
282 return args;
283 }
284
285