Added support for resolving symbolic links to FileSpec.

We use the symbolic link to resolver to find the target of the LLDB shlib
symlink if there is a symlink.  This allows us to find shlib-relative  resources
even when running under the testsuite, where _lldb.so is a symlink in the Python
resource directory.

Also changed a comment to be slightly more clear about what resolve_path in the
constructor for FileSpec means, since if we were actually using realpath() this
code wouldn't have been necessary.

http://reviews.llvm.org/D12984

llvm-svn: 248048

3 files changed, 34 insertions, 2 deletions

diff --git a/lldb/include/lldb/Host/FileSpec.h b/lldb/include/lldb/Host/FileSpec.h
index dd6da59f4ce..d8eb49f0ec1 100644
--- a/lldb/include/lldb/Host/FileSpec.h
+++ b/lldb/include/lldb/Host/FileSpec.h
@@ -73,7 +73,7 @@ public:
     ///     The full or partial path to a file.
     ///
     /// @param[in] resolve_path
-    ///     If \b true, then we resolve the path with realpath,
+    ///     If \b true, then we resolve the path, removing stray ../.. and so forth,
     ///     if \b false we trust the path is in canonical form already.
     ///
     /// @see FileSpec::SetFile (const char *path, bool resolve)
@@ -511,6 +511,9 @@ public:
 
     bool
     IsSymbolicLink () const;
+    
+    FileSpec
+    ResolveSymbolicLink () const;
 
     //------------------------------------------------------------------
     /// Get the memory cost of this object.
diff --git a/lldb/source/Host/common/FileSpec.cpp b/lldb/source/Host/common/FileSpec.cpp
index 9efdacb010b..f7225a4b0bc 100644
--- a/lldb/source/Host/common/FileSpec.cpp
+++ b/lldb/source/Host/common/FileSpec.cpp
@@ -811,6 +811,32 @@ FileSpec::IsSymbolicLink () const
 #endif
 }
 
+FileSpec
+FileSpec::ResolveSymbolicLink () const {
+    if (!IsSymbolicLink())
+    {
+        return *this;
+    }
+        
+    char resolved_path[PATH_MAX];
+    if (!GetPath (resolved_path, sizeof (resolved_path)))
+    {
+        return *this;
+    }
+        
+#ifdef _WIN32
+    return *this; // TODO make this work on win32
+#else
+    char real_path[PATH_MAX + 1];
+    if (realpath(resolved_path, real_path) == nullptr)
+    {
+        return *this;
+    }
+    
+    return FileSpec(real_path, false);
+#endif
+}
+
 uint32_t
 FileSpec::GetPermissions () const
 {
diff --git a/lldb/source/Host/common/HostInfoBase.cpp b/lldb/source/Host/common/HostInfoBase.cpp
index 7a6ea0c2b84..e7340c538f3 100644
--- a/lldb/source/Host/common/HostInfoBase.cpp
+++ b/lldb/source/Host/common/HostInfoBase.cpp
@@ -306,7 +306,10 @@ HostInfoBase::ComputeSharedLibraryDirectory(FileSpec &file_spec)
 
     FileSpec lldb_file_spec(
         Host::GetModuleFileSpecForHostAddress(reinterpret_cast<void *>(reinterpret_cast<intptr_t>(HostInfoBase::GetLLDBPath))));
-
+    
+    // This is necessary because when running the testsuite the shlib might be a symbolic link inside the Python resource dir.
+    lldb_file_spec = lldb_file_spec.ResolveSymbolicLink();
+    
     // Remove the filename so that this FileSpec only represents the directory.
     file_spec.GetDirectory() = lldb_file_spec.GetDirectory();