contrib/llvm/tools/lldb/source/Host/posix/HostInfoPosix.cpp

   1 //===-- HostInfoPosix.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/Host/posix/HostInfoPosix.h"
  11 #include "lldb/Utility/Log.h"
  12
  13 #include "llvm/ADT/SmallString.h"
  14 #include "llvm/ADT/Twine.h"
  15 #include "llvm/Support/Path.h"
  16 #include "llvm/Support/raw_ostream.h"
  17
  18 #include <grp.h>
  19 #include <limits.h>
  20 #include <mutex>
  21 #include <netdb.h>
  22 #include <pwd.h>
  23 #include <stdlib.h>
  24 #include <sys/types.h>
  25 #include <unistd.h>
  26
  27 using namespace lldb_private;
  28
  29 size_t HostInfoPosix::GetPageSize() { return ::getpagesize(); }
  30
  31 bool HostInfoPosix::GetHostname(std::string &s) {
  32   char hostname[PATH_MAX];
  33   hostname[sizeof(hostname) - 1] = '\0';
  34   if (::gethostname(hostname, sizeof(hostname) - 1) == 0) {
  35     struct hostent *h = ::gethostbyname(hostname);
  36     if (h)
  37       s.assign(h->h_name);
  38     else
  39       s.assign(hostname);
  40     return true;
  41   }
  42   return false;
  43 }
  44
  45 #ifdef __ANDROID__
  46 #include <android/api-level.h>
  47 #endif
  48 #if defined(__ANDROID_API__) && __ANDROID_API__ < 21
  49 #define USE_GETPWUID
  50 #endif
  51
  52 #ifdef USE_GETPWUID
  53 static std::mutex s_getpwuid_lock;
  54 #endif
  55
  56 const char *HostInfoPosix::LookupUserName(uint32_t uid,
  57                                           std::string &user_name) {
  58 #ifdef USE_GETPWUID
  59   // getpwuid_r is missing from android-9
  60   // make getpwuid thread safe with a mutex
  61   std::lock_guard<std::mutex> lock(s_getpwuid_lock);
  62   struct passwd *user_info_ptr = ::getpwuid(uid);
  63   if (user_info_ptr) {
  64     user_name.assign(user_info_ptr->pw_name);
  65     return user_name.c_str();
  66   }
  67 #else
  68   struct passwd user_info;
  69   struct passwd *user_info_ptr = &user_info;
  70   char user_buffer[PATH_MAX];
  71   size_t user_buffer_size = sizeof(user_buffer);
  72   if (::getpwuid_r(uid, &user_info, user_buffer, user_buffer_size,
  73                    &user_info_ptr) == 0) {
  74     if (user_info_ptr) {
  75       user_name.assign(user_info_ptr->pw_name);
  76       return user_name.c_str();
  77     }
  78   }
  79 #endif
  80   user_name.clear();
  81   return nullptr;
  82 }
  83
  84 const char *HostInfoPosix::LookupGroupName(uint32_t gid,
  85                                            std::string &group_name) {
  86 #ifndef __ANDROID__
  87   char group_buffer[PATH_MAX];
  88   size_t group_buffer_size = sizeof(group_buffer);
  89   struct group group_info;
  90   struct group *group_info_ptr = &group_info;
  91   // Try the threadsafe version first
  92   if (::getgrgid_r(gid, &group_info, group_buffer, group_buffer_size,
  93                    &group_info_ptr) == 0) {
  94     if (group_info_ptr) {
  95       group_name.assign(group_info_ptr->gr_name);
  96       return group_name.c_str();
  97     }
  98   } else {
  99     // The threadsafe version isn't currently working for me on darwin, but the
 100     // non-threadsafe version is, so I am calling it below.
 101     group_info_ptr = ::getgrgid(gid);
 102     if (group_info_ptr) {
 103       group_name.assign(group_info_ptr->gr_name);
 104       return group_name.c_str();
 105     }
 106   }
 107   group_name.clear();
 108 #else
 109   assert(false && "getgrgid_r() not supported on Android");
 110 #endif
 111   return NULL;
 112 }
 113
 114 uint32_t HostInfoPosix::GetUserID() { return getuid(); }
 115
 116 uint32_t HostInfoPosix::GetGroupID() { return getgid(); }
 117
 118 uint32_t HostInfoPosix::GetEffectiveUserID() { return geteuid(); }
 119
 120 uint32_t HostInfoPosix::GetEffectiveGroupID() { return getegid(); }
 121
 122 FileSpec HostInfoPosix::GetDefaultShell() { return FileSpec("/bin/sh"); }
 123
 124 bool HostInfoPosix::ComputePathRelativeToLibrary(FileSpec &file_spec,
 125                                                  llvm::StringRef dir) {
 126   Log *log = lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_HOST);
 127
 128   FileSpec lldb_file_spec = GetShlibDir();
 129   if (!lldb_file_spec)
 130     return false;
 131
 132   std::string raw_path = lldb_file_spec.GetPath();
 133   // drop library directory
 134   llvm::StringRef parent_path = llvm::sys::path::parent_path(raw_path);
 135
 136   // Most Posix systems (e.g. Linux/*BSD) will attempt to replace a */lib with
 137   // */bin as the base directory for helper exe programs.  This will fail if
 138   // the /lib and /bin directories are rooted in entirely different trees.
 139   if (log)
 140     log->Printf("HostInfoPosix::ComputePathRelativeToLibrary() attempting to "
 141                 "derive the %s path from this path: %s",
 142                 dir.data(), raw_path.c_str());
 143
 144   if (!parent_path.empty()) {
 145     // Now write in bin in place of lib.
 146     raw_path = (parent_path + dir).str();
 147
 148     if (log)
 149       log->Printf("Host::%s() derived the bin path as: %s", __FUNCTION__,
 150                   raw_path.c_str());
 151   } else {
 152     if (log)
 153       log->Printf("Host::%s() failed to find /lib/liblldb within the shared "
 154                   "lib path, bailing on bin path construction",
 155                   __FUNCTION__);
 156   }
 157   file_spec.GetDirectory().SetString(raw_path);
 158   return (bool)file_spec.GetDirectory();
 159 }
 160
 161 bool HostInfoPosix::ComputeSupportExeDirectory(FileSpec &file_spec) {
 162   return ComputePathRelativeToLibrary(file_spec, "/bin");
 163 }
 164
 165 bool HostInfoPosix::ComputeHeaderDirectory(FileSpec &file_spec) {
 166   FileSpec temp_file("/opt/local/include/lldb");
 167   file_spec.GetDirectory().SetCString(temp_file.GetPath().c_str());
 168   return true;
 169 }
 170
 171 bool HostInfoPosix::GetEnvironmentVar(const std::string &var_name,
 172                                       std::string &var) {
 173   if (const char *pvar = ::getenv(var_name.c_str())) {
 174     var = std::string(pvar);
 175     return true;
 176   }
 177   return false;
 178 }