Implements index validation for DrawElements.

(note: I also forgot to check in the changes to 
build_gles2_cmd_buffer.py from my last CL so
that's in here as well)

TEST=various unit tests
BUG=26101

Review URL: http://codereview.chromium.org/668131

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@40713 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 73 insertions, 6 deletions

diff --git a/gpu/command_buffer/service/buffer_manager.h b/gpu/command_buffer/service/buffer_manager.h
index e278a85..4afdaa0 100644
--- a/gpu/command_buffer/service/buffer_manager.h
+++ b/gpu/command_buffer/service/buffer_manager.h
@@ -7,7 +7,9 @@
 
 #include <map>
 #include "base/basictypes.h"
+#include "base/logging.h"
 #include "base/ref_counted.h"
+#include "base/scoped_ptr.h"
 #include "gpu/command_buffer/service/gl_utils.h"
 
 namespace gpu {
@@ -27,6 +29,7 @@ class BufferManager {
 
     explicit BufferInfo(GLuint buffer_id)
         : buffer_id_(buffer_id),
+          target_(0),
           size_(0) {
     }
 
@@ -34,17 +37,32 @@ class BufferManager {
       return buffer_id_;
     }
 
+    GLenum target() const {
+      return target_;
+    }
+
+    void set_target(GLenum target) {
+      DCHECK_EQ(target_, 0u);  // you can only set this once.
+      target_ = target;
+    }
+
     GLsizeiptr size() const {
       return size_;
     }
 
-    void set_size(GLsizeiptr size) {
-      size_ = size;
-    }
+    void SetSize(GLsizeiptr size);
+
+    // Sets a range of data for this buffer. Returns false if the offset or size
+    // is out of range.
+    bool SetRange(
+      GLintptr offset, GLsizeiptr size, const GLvoid * data);
 
-    // Returns the maximum value in the buffer for the given range
-    // interpreted as the given type.
-    GLuint GetMaxValueForRange(GLuint offset, GLsizei count, GLenum type);
+    // Gets the maximum value in the buffer for the given range interpreted as
+    // the given type. Returns false if offset and count are out of range.
+    // offset is in bytes.
+    // count is in elements of type.
+    bool GetMaxValueForRange(GLuint offset, GLsizei count, GLenum type,
+                             GLuint* max_value);
 
     bool IsDeleted() {
       return buffer_id_ == 0;
@@ -54,14 +72,63 @@ class BufferManager {
     friend class BufferManager;
     friend class base::RefCounted<BufferInfo>;
 
+    // Represents a range in a buffer.
+    class Range {
+     public:
+      Range(GLuint offset, GLsizei count, GLenum type)
+          : offset_(offset),
+            count_(count),
+            type_(type) {
+      }
+
+      // A less functor provided for std::map so it can find ranges.
+      struct Less {
+        bool operator() (const Range& lhs, const Range& rhs) {
+          if (lhs.offset_ != rhs.offset_) {
+            return lhs.offset_ < rhs.offset_;
+          }
+          if (lhs.count_ != rhs.count_) {
+            return lhs.count_ < rhs.count_;
+          }
+          return lhs.type_ < rhs.type_;
+        }
+      };
+
+     private:
+      GLuint offset_;
+      GLsizei count_;
+      GLenum type_;
+    };
+
     ~BufferInfo() { }
 
     void MarkAsDeleted() {
       buffer_id_ = 0;
+      shadow_.reset();
+      ClearCache();
     }
 
+    // Clears any cache of index ranges.
+    void ClearCache();
+
+    // Service side buffer id.
     GLuint buffer_id_;
+
+    // The type of buffer. 0 = unset, GL_BUFFER_ARRAY = vertex data,
+    // GL_ELEMENT_BUFFER_ARRAY = index data.
+    // Once set a buffer can not be used for something else.
+    GLenum target_;
+
+    // Size of buffer.
     GLsizeiptr size_;
+
+    // A copy of the data in the buffer. This data is only kept if the target
+    // is GL_ELEMENT_BUFFER_ARRAY
+    scoped_array<int8> shadow_;
+
+    // A map of ranges to the highest value in that range of a certain type.
+    typedef std::map<Range, GLuint, Range::Less> RangeToMaxValueMap;
+    RangeToMaxValueMap range_set_;
   };
 
   BufferManager() { }