[lldb][AIX] get host info for AIX

Author: HemangGadhavi

lldb/source/Host/CMakeLists.txt

@@ -141,6 +141,7 @@ else()
     add_host_subdirectory(aix
       aix/Host.cpp
       aix/HostInfoAIX.cpp
+      linux/Support.cpp
       )
   endif()
 endif()

lldb/source/Host/aix/Host.cpp

@@ -6,18 +6,172 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include <fcntl.h>
+#include <sstream>
+#include <sys/procfs.h>
+
 #include "lldb/Host/Host.h"
+#include "lldb/Host/linux/Support.h"
+#include "lldb/Utility/LLDBLog.h"
+#include "lldb/Utility/Log.h"
+#include "lldb/Utility/ProcessInfo.h"
 #include "lldb/Utility/Status.h"
+#include "llvm/BinaryFormat/XCOFF.h"
 
+using namespace llvm;
+using namespace lldb;
 using namespace lldb_private;
 
+namespace {
+enum class ProcessState {
+  Unknown,
+  Dead,
+  DiskSleep,
+  Idle,
+  Paging,
+  Parked,
+  Running,
+  Sleeping,
+  TracedOrStopped,
+  Zombie,
+};
+}
+
+static bool GetStatusInfo(::pid_t Pid, ProcessInstanceInfo &ProcessInfo,
+                          ProcessState &State, ::pid_t &TracerPid,
+                          ::pid_t &Tgid) {
+  Log *log = GetLog(LLDBLog::Host);
+
+  auto BufferOrError = getProcFile(Pid, "status");
+  if (!BufferOrError)
+    return false;
+
+  llvm::StringRef Rest = BufferOrError.get()->getBuffer();
+  while (!Rest.empty()) {
+    llvm::StringRef Line;
+    std::tie(Line, Rest) = Rest.split('\n');
+
+    if (Line.consume_front("Gid:")) {
+      // Real, effective, saved set, and file system GIDs. Read the first two.
+      Line = Line.ltrim();
+      uint32_t RGid, EGid;
+      Line.consumeInteger(10, RGid);
+      Line = Line.ltrim();
+      Line.consumeInteger(10, EGid);
+
+      ProcessInfo.SetGroupID(RGid);
+      ProcessInfo.SetEffectiveGroupID(EGid);
+    } else if (Line.consume_front("Uid:")) {
+      // Real, effective, saved set, and file system UIDs. Read the first two.
+      Line = Line.ltrim();
+      uint32_t RUid, EUid;
+      Line.consumeInteger(10, RUid);
+      Line = Line.ltrim();
+      Line.consumeInteger(10, EUid);
+
+      ProcessInfo.SetUserID(RUid);
+      ProcessInfo.SetEffectiveUserID(EUid);
+    } else if (Line.consume_front("PPid:")) {
+      ::pid_t PPid;
+      Line.ltrim().consumeInteger(10, PPid);
+      ProcessInfo.SetParentProcessID(PPid);
+    } else if (Line.consume_front("State:")) {
+      State = llvm::StringSwitch<ProcessState>(Line.ltrim().take_front(1))
+                  .Case("D", ProcessState::DiskSleep)
+                  .Case("I", ProcessState::Idle)
+                  .Case("R", ProcessState::Running)
+                  .Case("S", ProcessState::Sleeping)
+                  .CaseLower("T", ProcessState::TracedOrStopped)
+                  .Case("W", ProcessState::Paging)
+                  .Case("P", ProcessState::Parked)
+                  .Case("X", ProcessState::Dead)
+                  .Case("Z", ProcessState::Zombie)
+                  .Default(ProcessState::Unknown);
+      if (State == ProcessState::Unknown) {
+        LLDB_LOG(log, "Unknown process state {0}", Line);
+      }
+    } else if (Line.consume_front("TracerPid:")) {
+      Line = Line.ltrim();
+      Line.consumeInteger(10, TracerPid);
+    } else if (Line.consume_front("Tgid:")) {
+      Line = Line.ltrim();
+      Line.consumeInteger(10, Tgid);
+    }
+  }
+  return true;
+}
+
+static void GetExePathAndArch(::pid_t pid, ProcessInstanceInfo &process_info) {
+  Log *log = GetLog(LLDBLog::Process);
+  std::string ExePath(PATH_MAX, '\0');
+  struct psinfo psinfoData;
+
+  // We can't use getProcFile here because proc/[pid]/exe is a symbolic link.
+  llvm::SmallString<64> ProcExe;
+  (llvm::Twine("/proc/") + llvm::Twine(pid) + "/cwd").toVector(ProcExe);
+
+  ssize_t len = readlink(ProcExe.c_str(), &ExePath[0], PATH_MAX);
+  if (len > 0) {
+    ExePath.resize(len);
+
+    struct stat statData;
+
+    std::ostringstream oss;
+
+    oss << "/proc/" << std::dec << pid << "/psinfo";
+    assert(stat(oss.str().c_str(), &statData) == 0);
+
+    const int fd = open(oss.str().c_str(), O_RDONLY);
+    assert(fd >= 0);
+
+    ssize_t readNum = read(fd, &psinfoData, sizeof(psinfoData));
+    assert(readNum >= 0);
+
+    close(fd);
+  } else {
+    LLDB_LOG(log, "failed to read link exe link for {0}: {1}", pid,
+             Status(errno, eErrorTypePOSIX));
+    ExePath.resize(0);
+  }
+
+  llvm::StringRef PathRef(&(psinfoData.pr_psargs[0]));
+
+  if (!PathRef.empty()) {
+    process_info.GetExecutableFile().SetFile(PathRef, FileSpec::Style::native);
+    ArchSpec arch_spec = ArchSpec();
+    arch_spec.SetArchitecture(eArchTypeXCOFF, XCOFF::TCPU_PPC64,
+                              LLDB_INVALID_CPUTYPE, llvm::Triple::AIX);
+    process_info.SetArchitecture(arch_spec);
+  }
+}
+
+static bool GetProcessAndStatInfo(::pid_t pid,
+                                  ProcessInstanceInfo &process_info,
+                                  ProcessState &State, ::pid_t &tracerpid) {
+  ::pid_t tgid;
+  tracerpid = 0;
+  process_info.Clear();
+
+  process_info.SetProcessID(pid);
+
+  GetExePathAndArch(pid, process_info);
+
+  // Get User and Group IDs and get tracer pid.
+  if (!GetStatusInfo(pid, process_info, State, tracerpid, tgid))
+    return false;
+
+  return true;
+}
+
 uint32_t Host::FindProcessesImpl(const ProcessInstanceInfoMatch &match_info,
                                  ProcessInstanceInfoList &process_infos) {
   return 0;
 }
 
 bool Host::GetProcessInfo(lldb::pid_t pid, ProcessInstanceInfo &process_info) {
-  return false;
+  ::pid_t tracerpid;
+  ProcessState State;
+  return GetProcessAndStatInfo(pid, process_info, State, tracerpid);
 }
 
 Status Host::ShellExpandArguments(ProcessLaunchInfo &launch_info) {