Xcode: Save object id values in CMakeCache.txt (#11690)

For project and target objects, save their ids in CMakeCache.txt.

Hopefully, that will be enough to allow user settings to be saved
across multiple CMake generate operations. Other object types may
also need their ids saved: if so, more code than this commit
will be necessary...

1 files changed, 21 insertions, 19 deletions

diff --git a/Source/cmXCodeObject.cxx b/Source/cmXCodeObject.cxx
index 30e5076c46..30ade9637d 100644
--- a/Source/cmXCodeObject.cxx
+++ b/Source/cmXCodeObject.cxx
@@ -12,6 +12,8 @@
 #include "cmXCodeObject.h"
 #include "cmSystemTools.h"
 
+#include <CoreFoundation/CoreFoundation.h> // CFUUIDCreate
+
 //----------------------------------------------------------------------------
 const char* cmXCodeObject::PBXTypeNames[] = {
     "PBXGroup", "PBXBuildStyle", "PBXProject", "PBXHeadersBuildPhase", 
@@ -39,35 +41,35 @@ cmXCodeObject::cmXCodeObject(PBXType ptype, Type type)
   this->PBXTargetDependencyValue = 0;
   this->Target = 0;
   this->Object =0;
-  
+
   this->IsA = ptype;
+
   if(type == OBJECT)
     {
-    cmOStringStream str;
-    str << (void*)this;
-    str << (void*)this;
-    str << (void*)this;
-    this->Id = str.str();
+    // Set the Id of an Xcode object to a unique string for each instance.
+    // However the Xcode user file references certain Ids: for those cases,
+    // override the generated Id using SetId().
+    //
+    char cUuid[40] = {0};
+    CFUUIDRef uuid = CFUUIDCreate(kCFAllocatorDefault);
+    CFStringRef s = CFUUIDCreateString(kCFAllocatorDefault, uuid);
+    CFStringGetCString(s, cUuid, sizeof(cUuid), kCFStringEncodingUTF8);
+    this->Id = cUuid;
+    CFRelease(s);
+    CFRelease(uuid);
     }
   else
     {
-    this->Id = 
-      "Temporary cmake object, should not be refered to in xcode file";
-    }
-  cmSystemTools::ReplaceString(this->Id, "0x", "");
-  this->Id = cmSystemTools::UpperCase(this->Id);
-  if(this->Id.size() < 24)
-    {
-    int diff = 24 - this->Id.size();
-    for(int i =0; i < diff; ++i)
-      {
-      this->Id += "0";
-      }
+    this->Id =
+      "Temporary cmake object, should not be referred to in Xcode file";
     }
+
+  cmSystemTools::ReplaceString(this->Id, "-", "");
   if(this->Id.size() > 24)
     {
-    this->Id = this->Id.substr(0,24);
+    this->Id = this->Id.substr(0, 24);
     }
+
   this->TypeValue = type;
   if(this->TypeValue == OBJECT)
     {