QPID-3540 Typecasting and alignment requirements for various platforms

On sparc platform:

SchemaHash::update() fails when the hash byte array is cast as two quadwords
in a union. This fix uses the union in the definition of the hash byte array
to coerce the compiler to place them in quadword alignment when they are
created.

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk/qpid@1183456 13f79535-47bb-0310-9956-ffa450edef68

2 files changed, 10 insertions, 11 deletions

diff --git a/cpp/src/qmf/engine/SchemaImpl.cpp b/cpp/src/qmf/engine/SchemaImpl.cpp
index f75663e131..9d363d3012 100644
--- a/cpp/src/qmf/engine/SchemaImpl.cpp
+++ b/cpp/src/qmf/engine/SchemaImpl.cpp
@@ -35,17 +35,17 @@ using qpid::framing::Uuid;
 SchemaHash::SchemaHash()
 {
     for (int idx = 0; idx < 16; idx++)
-        hash[idx] = 0x5A;
+        hash.b[idx] = 0x5A;
 }
 
 void SchemaHash::encode(Buffer& buffer) const
 {
-    buffer.putBin128(hash);
+    buffer.putBin128(hash.b);
 }
 
 void SchemaHash::decode(Buffer& buffer)
 {
-    buffer.getBin128(hash);
+    buffer.getBin128(hash.b);
 }
 
 void SchemaHash::update(uint8_t data)
@@ -55,12 +55,8 @@ void SchemaHash::update(uint8_t data)
 
 void SchemaHash::update(const char* data, uint32_t len)
 {
-    union h {
-        uint8_t  b[16];
-        uint64_t q[2];
-    }* h = reinterpret_cast<union h*>(&hash[0]);
-    uint64_t* first  = &h->q[0];
-    uint64_t* second = &h->q[1];
+    uint64_t* first  = &hash.q[0];
+    uint64_t* second = &hash.q[1];
     for (uint32_t idx = 0; idx < len; idx++) {
         *first = *first ^ (uint64_t) data[idx];
         *second = *second << 1;
diff --git a/cpp/src/qmf/engine/SchemaImpl.h b/cpp/src/qmf/engine/SchemaImpl.h
index 8b079a5ec6..683fb6f8f0 100644
--- a/cpp/src/qmf/engine/SchemaImpl.h
+++ b/cpp/src/qmf/engine/SchemaImpl.h
@@ -35,7 +35,10 @@ namespace engine {
     //       they've been registered.
 
     class SchemaHash {
-        uint8_t hash[16];
+        union h {
+            uint8_t  b[16];
+            uint64_t q[2];
+        } hash;
     public:
         SchemaHash();
         void encode(qpid::framing::Buffer& buffer) const;
@@ -47,7 +50,7 @@ namespace engine {
         void update(Direction d) { update((uint8_t) d); }
         void update(Access a) { update((uint8_t) a); }
         void update(bool b) { update((uint8_t) (b ? 1 : 0)); }
-        const uint8_t* get() const { return hash; }
+        const uint8_t* get() const { return hash.b; }
         bool operator==(const SchemaHash& other) const;
         bool operator<(const SchemaHash& other) const;
         bool operator>(const SchemaHash& other) const;