addresses #1567

write function to create a row descriptor
untested, just verified that it compiles
also currently unused

git-svn-id: file:///svn/mysql/tokudb-engine/src@10950 c7de825b-a66e-492c-adef-691d508d4ae1

storage/tokudb/hatoku_cmp.cc

@@ -1133,7 +1133,7 @@ int tokudb_prefix_cmp_packed_key(DB *file, const DBT *keya, const DBT *keyb) {
 // outputs a descriptor for key into buf. num_bytes returns number of bytes used in buf
 // to store the descriptor
 //
-int create_key_descriptor(KEY* key, uchar* buf, u_int32_t* num_bytes) {
+int create_toku_key_descriptor(KEY* key, uchar* buf) {
     int ret_val = 0;
     uchar* pos = buf;
     u_int32_t num_bytes_in_field = 0;
@@ -1217,6 +1217,62 @@ int create_key_descriptor(KEY* key, uchar* buf, u_int32_t* num_bytes) {
             
         }
     }
-    *num_bytes = pos - buf;
-    return ret_val;
+    return pos - buf;
+}
+
+int create_toku_descriptor(uchar* buf, bool is_first_hpk, KEY* first_key, bool is_second_hpk, KEY* second_key) {
+    uchar* pos = buf + 4;
+    u_int32_t num_bytes = 0;
+    u_int32_t offset = 0;
+
+    if (is_first_hpk) {
+        pos[0] = 1;
+        pos++;
+        goto exit;
+    }
+
+    //
+    // first key is NOT a hidden primary key, so we now pack first_key
+    //
+    pos[0] = 0;
+    pos++;
+    num_bytes = create_toku_key_descriptor(first_key, pos);
+    pos += num_bytes;
+
+    //
+    // if we do not have a second key, we can jump to exit right now
+    // we do not have a second key if it is not a hidden primary key
+    // and if second_key is NULL
+    //
+    if (!is_second_hpk && (second_key == NULL) ) {
+        goto exit;
+    }
+    //
+    // at this point, we have a second key, so we need to write an offset
+    // into the first four bytes
+    //
+    offset = pos - buf;
+    buf[0] = (uchar)(offset & 255);
+    buf[1] = (uchar)((offset >> 8) & 255);
+    buf[2] = (uchar)((offset >> 16) & 255);
+    buf[3] = (uchar)((offset >> 24) & 255);
+
+    //
+    // if we have a second key, and it is an hpk, we need to pack it, and
+    // write in the offset to this position in the first four bytes
+    //
+    if (is_second_hpk) {
+        pos[0] = 1;
+        pos++;
+        goto exit;
+    }
+
+    pos[0] = 0;
+    pos++;
+    num_bytes = create_toku_key_descriptor(second_key, pos);
+    pos += num_bytes;
+    
+    
+exit:
+    return pos - buf;
 }

storage/tokudb/hatoku_cmp.h

@@ -121,7 +121,7 @@ int tokudb_cmp_primary_key(DB *file, const DBT *keya, const DBT *keyb);
 //TODO: QQQ Only do one direction for prefix.
 int tokudb_prefix_cmp_packed_key(DB *file, const DBT *keya, const DBT *keyb);
 
-int create_key_descriptor(KEY* key, uchar* buf, u_int32_t* num_bytes);
+int create_toku_key_descriptor(KEY* key, uchar* buf);
 
 #endif