Refactor for GPU command buffer PUTSTR code generator.

gpu/command_buffer/client/gles2_implementation.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // A class to emulate GLES2 over command buffers.
 
 #include "gpu/command_buffer/client/gles2_implementation.h"
 
 #include <GLES2/gl2ext.h>
 #include <GLES2/gl2extchromium.h>
@@ skipping 4503 matching lines @@
   // TODO(zmo): Implement client side caching.
   return false;
 }
 
 bool GLES2Implementation::GetSamplerParameterivHelper(
     GLuint /* sampler */, GLenum /* pname */, GLint* /* params */) {
   // TODO(zmo): Implement client side caching.
   return false;
 }
 
+bool GLES2Implementation::PackStringsToBucket(GLsizei count,
+                                              const char* const* str,
+                                              const GLint* length,
+                                              const char* func_name) {
+  DCHECK_LE(0, count);
+  // Compute the total size.
+  base::CheckedNumeric<size_t> total_size = count;
+  total_size += 1;
+  total_size *= sizeof(GLint);
+  if (!total_size.IsValid()) {
+    SetGLError(GL_INVALID_VALUE, func_name, "overflow");
+    return false;
+  }
+  size_t header_size = total_size.ValueOrDefault(0);
+  std::vector<GLint> header(count + 1);
+  header[0] = static_cast<GLint>(count);
+  for (GLsizei ii = 0; ii < count; ++ii) {
+    GLint len = 0;
+    if (str[ii]) {
+      len = (length && length[ii] >= 0)
+                ? length[ii]
+                : base::checked_cast<GLint>(strlen(str[ii]));
+    }
+    total_size += len;
+    total_size += 1;  // NULL at the end of each char array.
+    if (!total_size.IsValid()) {
+      SetGLError(GL_INVALID_VALUE, func_name, "overflow");
+      return false;
+    }
+    header[ii + 1] = len;
+  }
+  // Pack data into a bucket on the service.
+  helper_->SetBucketSize(kResultBucketId, total_size.ValueOrDefault(0));
+  size_t offset = 0;
+  for (GLsizei ii = 0; ii <= count; ++ii) {
+    const char* src =
+        (ii == 0) ? reinterpret_cast<const char*>(&header[0]) : str[ii - 1];
+    base::CheckedNumeric<size_t> checked_size =
+        (ii == 0) ? header_size : static_cast<size_t>(header[ii]);
+    if (ii > 0) {
+      checked_size += 1;  // NULL in the end.
+    }
+    if (!checked_size.IsValid()) {
+      SetGLError(GL_INVALID_VALUE, func_name, "overflow");
+      return false;
+    }
+    size_t size = checked_size.ValueOrDefault(0);
+    while (size) {
+      ScopedTransferBufferPtr buffer(size, helper_, transfer_buffer_);
+      if (!buffer.valid() || buffer.size() == 0) {
+        SetGLError(GL_OUT_OF_MEMORY, func_name, "too large");
+        return false;
+      }
+      size_t copy_size = buffer.size();
+      if (ii > 0 && buffer.size() == size)
+        --copy_size;
+      if (copy_size)
+        memcpy(buffer.address(), src, copy_size);
+      if (copy_size < buffer.size()) {
+        // Append NULL in the end.
+        DCHECK(copy_size + 1 == buffer.size());
+        char* str = reinterpret_cast<char*>(buffer.address());
+        str[copy_size] = 0;
+      }
+      helper_->SetBucketData(kResultBucketId, offset, buffer.size(),
+                             buffer.shm_id(), buffer.offset());
+      offset += buffer.size();
+      src += buffer.size();
+      size -= buffer.size();
+    }
+  }
+  DCHECK_EQ(total_size.ValueOrDefault(0), offset);
+  return true;
+}
+
 // Include the auto-generated part of this file. We split this because it means
 // we can easily edit the non-auto generated parts right here in this file
 // instead of having to edit some template or the code generator.
 #include "gpu/command_buffer/client/gles2_implementation_impl_autogen.h"
 
 }  // namespace gles2
 }  // namespace gpu