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diff --git a/mailnews/extensions/fts3/src/nsGlodaRankerFunction.cpp b/mailnews/extensions/fts3/src/nsGlodaRankerFunction.cpp
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+++ b/mailnews/extensions/fts3/src/nsGlodaRankerFunction.cpp
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+/* ***** BEGIN LICENSE BLOCK *****
+ *   Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is Thunderbird Global Database.
+ *
+ * The Initial Developer of the Original Code is the Mozilla Foundation.
+ * Portions created by the Initial Developer are Copyright (C) 2010
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *   Andrew Sutherland <asutherland@asutherland.org>
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either the GNU General Public License Version 2 or later (the "GPL"), or
+ * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+#include "nsGlodaRankerFunction.h"
+#include "mozIStorageValueArray.h"
+
+#include "sqlite3.h"
+
+#include "nsCOMPtr.h"
+#include "nsVariant.h"
+#include "nsComponentManagerUtils.h"
+
+#ifndef SQLITE_VERSION_NUMBER
+#error "We need SQLITE_VERSION_NUMBER defined!"
+#endif
+
+NS_IMPL_ISUPPORTS(nsGlodaRankerFunction, mozIStorageFunction)
+
+nsGlodaRankerFunction::nsGlodaRankerFunction()
+{
+}
+
+nsGlodaRankerFunction::~nsGlodaRankerFunction()
+{
+}
+
+static uint32_t COLUMN_SATURATION[] = {10, 1, 1, 1, 1};
+
+/**
+ * Our ranking function basically just multiplies the weight of the column
+ * against the number of (saturating) matches.
+ *
+ * The original code is a SQLite example ranking function, although somewhat
+ * rather modified at this point.  All SQLite code is public domain, so we are
+ * subsuming it to MPL1.1/LGPL2/GPL2.
+ */
+NS_IMETHODIMP
+nsGlodaRankerFunction::OnFunctionCall(mozIStorageValueArray *aArguments,
+                                      nsIVariant **_result)
+{
+  // all argument names are maintained from the original SQLite code.
+  uint32_t nVal;
+  nsresult rv = aArguments->GetNumEntries(&nVal);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  /* Check that the number of arguments passed to this function is correct.
+   * If not, return an error. Set aArgsData to point to the array
+   * of unsigned integer values returned by FTS3 function. Set nPhrase
+   * to contain the number of reportable phrases in the users full-text
+   * query, and nCol to the number of columns in the table.
+   */
+  if (nVal < 1)
+    return NS_ERROR_INVALID_ARG;
+
+  uint32_t lenArgsData;
+  uint32_t *aArgsData = (uint32_t *)aArguments->AsSharedBlob(0, &lenArgsData);
+
+  uint32_t nPhrase = aArgsData[0];
+  uint32_t nCol = aArgsData[1];
+  if (nVal != (1 + nCol))
+    return NS_ERROR_INVALID_ARG;
+
+  double score = 0.0;
+
+  // SQLite 3.6.22 has a different matchinfo layout than SQLite 3.6.23+
+#if SQLITE_VERSION_NUMBER <= 3006022
+  /* Iterate through each phrase in the users query. */
+  for (uint32_t iPhrase = 0; iPhrase < nPhrase; iPhrase++) {
+    // in SQ
+    for (uint32_t iCol = 0; iCol < nCol; iCol++) {
+      uint32_t nHitCount = aArgsData[2 + (iPhrase+1)*nCol + iCol];
+      double weight = aArguments->AsDouble(iCol+1);
+      if (nHitCount > 0) {
+        score += (nHitCount > COLUMN_SATURATION[iCol]) ?
+          (COLUMN_SATURATION[iCol] * weight) :
+          (nHitCount * weight);
+      }
+    }
+  }
+#else
+  /* Iterate through each phrase in the users query. */
+  for (uint32_t iPhrase = 0; iPhrase < nPhrase; iPhrase++) {
+    /* Now iterate through each column in the users query. For each column,
+    ** increment the relevancy score by:
+    **
+    **   (<hit count> / <global hit count>) * <column weight>
+    **
+    ** aPhraseinfo[] points to the start of the data for phrase iPhrase. So
+    ** the hit count and global hit counts for each column are found in 
+    ** aPhraseinfo[iCol*3] and aPhraseinfo[iCol*3+1], respectively.
+    */
+    uint32_t *aPhraseinfo = &aArgsData[2 + iPhrase*nCol*3];
+    for (uint32_t iCol = 0; iCol < nCol; iCol++) {
+      uint32_t nHitCount = aPhraseinfo[3 * iCol];
+      double weight = aArguments->AsDouble(iCol+1);
+      if (nHitCount > 0) {
+        score += (nHitCount > COLUMN_SATURATION[iCol]) ?
+          (COLUMN_SATURATION[iCol] * weight) :
+          (nHitCount * weight);
+      }
+    }
+  }
+#endif
+
+  nsCOMPtr<nsIWritableVariant> result = new nsVariant();
+   
+  rv = result->SetAsDouble(score);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  NS_ADDREF(*_result = result);
+  return NS_OK;
+}