Use /data/local/tmp as temp directory on android

[tberghammer]

Summary

Use /data/local/tmp as temp directory on android

If no temp directory specified by the user on android then fall back
to /data/local/tmp what is always present on the device. It removes
the dependency of specifying TMPDIR for executing platform commands
on android.

[tberghammer]

Overwrite the ComputeGlobalTempFileDirectory function instead of ComputeProcessTempFileDirectory

[ovyalov]

Please see my comment.

source/Host/android/HostInfoAndroid.cpp

99 ↗

(On Diff #25204)

What do you think about adding lldb sub directory - i.e. /data/local/tmp/lldb?
In this case it will be consistent with default implementation (https://github.com/llvm-mirror/lldb/blob/789afe8e6565a1370b2f34e075e9ca5289d362f8/source/Host/common/HostInfoBase.cpp#L360) .

[tberghammer]

Changing the default temp directory to include /lldb suffix

[labath]

LGTM.

lldb/trunk/include/lldb/Host/HostInfoBase.h

public:
     //------------------------------------------------------------------
     static bool GetLLDBPath(lldb::PathType type, FileSpec &file_spec);
 
   protected:
     static bool ComputeSharedLibraryDirectory(FileSpec &file_spec);
     static bool ComputeSupportExeDirectory(FileSpec &file_spec);
     static bool ComputeProcessTempFileDirectory(FileSpec &file_spec);
     static bool ComputeGlobalTempFileDirectory(FileSpec &file_spec);
+    static bool ComputeTempFileBaseDirectory(FileSpec &file_spec);
     static bool ComputeHeaderDirectory(FileSpec &file_spec);
     static bool ComputeSystemPluginsDirectory(FileSpec &file_spec);
     static bool ComputeClangDirectory(FileSpec &file_spec);
     static bool ComputeUserPluginsDirectory(FileSpec &file_spec);
 
     static void ComputeHostArchitectureSupport(ArchSpec &arch_32, ArchSpec &arch_64);
 };
 }
 
 #endif

lldb/trunk/include/lldb/Host/android/HostInfoAndroid.h

class HostInfoAndroid : public HostInfoLinux
     friend class HostInfoBase;
 
   public:
     static FileSpec GetDefaultShell();
     static FileSpec ResolveLibraryPath (const std::string& path, const ArchSpec& arch);
 
   protected:
     static void ComputeHostArchitectureSupport(ArchSpec &arch_32, ArchSpec &arch_64);
+    static bool ComputeTempFileBaseDirectory(FileSpec &file_spec);
 };
 
 } // end of namespace lldb_private
 
 #endif // #ifndef lldb_Host_android_HostInfoAndroid_h_

lldb/trunk/source/Host/android/HostInfoAndroid.cpp

for (const StringRef& path : ld_paths)
         file_candidate.AppendPathComponent(module_path.c_str());
 
         if (file_candidate.Exists())
             return file_candidate;
     }
 
     return FileSpec();
 }
+
+bool
+HostInfoAndroid::ComputeTempFileBaseDirectory(FileSpec &file_spec)
+{
+    if (HostInfoLinux::ComputeTempFileBaseDirectory(file_spec))
+        return true;
+
+    // If the default mechanism for computing the temp directory failed then
+    // fall back to /data/local/tmp
+    file_spec = FileSpec("/data/local/tmp", false);
+    return true;
+}

lldb/trunk/source/Host/common/HostInfoBase.cpp

 {
     return GetLLDBPath(lldb::ePathTypeLLDBShlibDir, file_spec);
 }
 
 bool
 HostInfoBase::ComputeProcessTempFileDirectory(FileSpec &file_spec)
 {
     FileSpec temp_file_spec;
-    if (!ComputeGlobalTempFileDirectory(temp_file_spec))
+    if (!HostInfo::ComputeGlobalTempFileDirectory(temp_file_spec))
         return false;
 
     std::string pid_str;
     llvm::raw_string_ostream pid_stream(pid_str);
     pid_stream << Host::GetCurrentProcessID();
     temp_file_spec.AppendPathComponent(pid_stream.str().c_str());
     std::string final_path = temp_file_spec.GetPath();
     if (!FileSystem::MakeDirectory(final_path.c_str(), eFilePermissionsDirectoryDefault).Success())
         return false;
 
     // Make an atexit handler to clean up the process specify LLDB temp dir
     // and all of its contents.
     ::atexit(CleanupProcessSpecificLLDBTempDir);
     file_spec.GetDirectory().SetCStringWithLength(final_path.c_str(), final_path.size());
     return true;
 }
 
 bool
-HostInfoBase::ComputeGlobalTempFileDirectory(FileSpec &file_spec)
+HostInfoBase::ComputeTempFileBaseDirectory(FileSpec &file_spec)
 {
     file_spec.Clear();
 
     const char *tmpdir_cstr = getenv("TMPDIR");
-    if (tmpdir_cstr == NULL)
+    if (tmpdir_cstr == nullptr)
     {
         tmpdir_cstr = getenv("TMP");
-        if (tmpdir_cstr == NULL)
+        if (tmpdir_cstr == nullptr)
             tmpdir_cstr = getenv("TEMP");
     }
     if (!tmpdir_cstr)
         return false;
 
-    FileSpec temp_file_spec(tmpdir_cstr, false);
+    file_spec = FileSpec(tmpdir_cstr, false);
+    return true;
+}
+
+bool
+HostInfoBase::ComputeGlobalTempFileDirectory(FileSpec &file_spec)
+{
+    file_spec.Clear();
+
+    FileSpec temp_file_spec;
+    if (!HostInfo::ComputeTempFileBaseDirectory(temp_file_spec))
+        return false;
+
     temp_file_spec.AppendPathComponent("lldb");
     if (!FileSystem::MakeDirectory(temp_file_spec.GetPath().c_str(), eFilePermissionsDirectoryDefault).Success())
         return false;
 
     file_spec = temp_file_spec;
     return true;
 }