From d6297f7d096cee1ce180ac7bc26604a179e742c5 Mon Sep 17 00:00:00 2001
From: Mathias Agopian <mathias@google.com>
Date: Mon, 17 May 2010 17:27:26 -0700
Subject: [PATCH] fix some bugs in SharedBufferStack::resize

added buffers should now be labeled properly.

Change-Id: I28aa753fbe89ab89134e7753575319478934c7fa
---
 include/private/surfaceflinger/SharedBufferStack.h | 9 +++++----
 libs/surfaceflinger_client/SharedBufferStack.cpp   | 6 ++++--
 2 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/include/private/surfaceflinger/SharedBufferStack.h b/include/private/surfaceflinger/SharedBufferStack.h
index c23832d49..a1a02e06a 100644
--- a/include/private/surfaceflinger/SharedBufferStack.h
+++ b/include/private/surfaceflinger/SharedBufferStack.h
@@ -295,7 +295,8 @@ private:
             friend class BufferList;
             uint32_t mask, curr;
             const_iterator(uint32_t mask) :
-                mask(mask), curr(31 - __builtin_clz(mask)) { }
+                mask(mask), curr(__builtin_clz(mask)) {
+            }
         public:
             inline bool operator == (const const_iterator& rhs) const {
                 return mask == rhs.mask;
@@ -304,9 +305,9 @@ private:
                 return mask != rhs.mask;
             }
             inline int operator *() const { return curr; }
-            inline const const_iterator& operator ++(int) {
-                mask &= ~curr;
-                curr = 31 - __builtin_clz(mask);
+            inline const const_iterator& operator ++() {
+                mask &= ~(1<<(31-curr));
+                curr = __builtin_clz(mask);
                 return *this;
             }
         };
diff --git a/libs/surfaceflinger_client/SharedBufferStack.cpp b/libs/surfaceflinger_client/SharedBufferStack.cpp
index 4a980268f..570574863 100644
--- a/libs/surfaceflinger_client/SharedBufferStack.cpp
+++ b/libs/surfaceflinger_client/SharedBufferStack.cpp
@@ -560,6 +560,7 @@ status_t SharedBufferServer::resize(int newNumBuffers)
     int base = numBuffers;
     int32_t avail = stack.available;
     int tail = head - avail + 1;
+
     if (tail >= 0) {
         int8_t* const index = const_cast<int8_t*>(stack.index);
         const int nb = numBuffers - head;
@@ -573,8 +574,9 @@ status_t SharedBufferServer::resize(int newNumBuffers)
     // fill the new free space with unused buffers
     BufferList::const_iterator curr(mBufferList.free_begin());
     for (int i=0 ; i<extra ; i++) {
-        stack.index[base+i] = *curr++;
-        mBufferList.add(stack.index[base+i]);
+        stack.index[base+i] = *curr;
+        mBufferList.add(*curr);
+        ++curr;
     }
 
     mNumBuffers = newNumBuffers;