SERVER-5710 Changed KeyPattern.hasField() sematics to consider dotted field prefixes.

1 files changed, 123 insertions, 0 deletions

diff --git a/src/mongo/db/field_ref.cpp b/src/mongo/db/field_ref.cpp
new file mode 100644
index 00000000000..7b9f5631140
--- /dev/null
+++ b/src/mongo/db/field_ref.cpp
@@ -0,0 +1,123 @@
+/**
+ *    Copyright (C) 2012 10gen Inc.
+ *
+ *    This program is free software: you can redistribute it and/or  modify
+ *    it under the terms of the GNU Affero General Public License, version 3,
+ *    as published by the Free Software Foundation.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    GNU Affero General Public License for more details.
+ *
+ *    You should have received a copy of the GNU Affero General Public License
+ *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "mongo/db/field_ref.h"
+#include "mongo/util/assert_util.h"
+
+namespace mongo {
+
+    void FieldRef::parse(const StringData& dottedField) {
+        if (dottedField.size() == 0) {
+            return;
+        }
+
+        // We guarantee that accesses through getPart() will be valid while 'this' is. So we
+        // take a copy. We're going to be "chopping" up the copy into c-strings.
+        _fieldBase.reset(new char[dottedField.size()+1]);
+        dottedField.copyTo( _fieldBase.get(), true );
+
+        // Separate the field parts using '.' as a delimiter.
+        char* beg = _fieldBase.get();
+        char* cur = beg;
+        char* end = beg + dottedField.size();
+        while (true) {
+            if (cur != end && *cur != '.') {
+                cur++;
+                continue;
+            }
+
+            appendPart(StringData(beg, cur - beg));
+
+            if (cur != end) {
+                *cur = '\0';
+                beg = ++cur;
+                continue;
+            }
+
+            break;
+        }
+    }
+
+    void FieldRef::setPart(size_t i, const StringData& part) {
+        dassert(i < _size);
+
+        if (_replacements.size() != _size) {
+            _replacements.resize(_size);
+        }
+
+        _replacements[i] = part.toString();
+        if (i < kReserveAhead) {
+            _fixed[i] = _replacements[i];
+        }
+        else {
+            _variable[getIndex(i)] = _replacements[i];
+        }
+    }
+
+    size_t FieldRef::appendPart(const StringData& part) {
+        if (_size < kReserveAhead) {
+            _fixed[_size] = part;
+        }
+        else {
+            _variable.push_back(part);
+        }
+        return ++_size;
+    }
+
+    StringData FieldRef::getPart(size_t i) const {
+        dassert(i < _size);
+
+        if (i < kReserveAhead) {
+            return _fixed[i];
+        }
+        else {
+            return _variable[getIndex(i)];
+        }
+    }
+
+    void FieldRef::clear() {
+        _size = 0;
+        _variable.clear();
+        _fieldBase.reset();
+        _replacements.clear();
+    }
+
+    std::string FieldRef::dottedField() const {
+        std::string res;
+        if (_size == 0) {
+            return res;
+        }
+
+        res.append(_fixed[0].rawData(), _fixed[0].size());
+        for (size_t i=1; i<_size; i++) {
+            res.append(1, '.');
+            StringData part = getPart(i);
+            res.append(part.rawData(), part.size());
+        }
+        return res;
+    }
+
+    size_t FieldRef::numReplaced() const {
+        size_t res = 0;
+        for (size_t i = 0; i < _replacements.size(); i++) {
+            if (!_replacements[i].empty()) {
+                res++;
+            }
+        }
+        return res;
+    }
+
+} // namespace mongo