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+/*
+ * Copyright (c) 2017-2024 OARC, Inc.
+ * Copyright (c) 2011-2017, IIS - The Internet Foundation in Sweden
+ * All rights reserved.
+ *
+ * This file is part of PacketQ.
+ *
+ * PacketQ is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * PacketQ 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with PacketQ. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __packetq_variant_h
+#define __packetq_variant_h
+
+#include <cstdlib>
+
+#include "MurmurHash3.h"
+#include "refcountstring.h"
+
+namespace packetq {
+
+inline std::size_t hash_bytes(const char* bytes, int len)
+{
+ uint32_t result = 0;
+ MurmurHash3_x86_32(bytes, len, 0, &result);
+ return result;
+}
+
+// must be defined in this order - see the "if" statement
+#define COLTYPE_MAX 4
+namespace Coltype {
+ enum Type {
+ _bool = 0,
+ _int = 1,
+ _float = 2,
+ _text = 3,
+ };
+};
+
+typedef bool bool_column;
+static const int bool_size = sizeof(bool_column);
+static const int bool_align = ((sizeof(bool_column) / sizeof(void*)) + 1) * sizeof(void*);
+
+typedef int int_column;
+static const int int_size = sizeof(int_column);
+static const int int_align = ((sizeof(int_column) / sizeof(void*)) + 1) * sizeof(void*);
+
+typedef double float_column;
+static const int float_size = sizeof(float_column);
+static const int float_align = ((sizeof(float_column) / sizeof(void*)) + 1) * sizeof(void*);
+
+typedef RefCountString* text_column;
+static const int text_size = sizeof(text_column);
+static const int text_align = ((sizeof(text_column) / sizeof(void*)) + 1) * sizeof(void*);
+
+inline bool_column convert_column_to_bool(float_column v) { return v; }
+inline bool_column convert_column_to_bool(int_column v) { return v; }
+inline bool_column convert_column_to_bool(bool_column v) { return v; }
+inline bool_column convert_column_to_bool(text_column v)
+{
+ return std::atoi(v->data);
+}
+
+inline int_column convert_column_to_int(float_column v) { return int(v); }
+inline int_column convert_column_to_int(int_column v) { return v; }
+inline int_column convert_column_to_int(bool_column v) { return v; }
+inline int_column convert_column_to_int(text_column v)
+{
+ return v->data[0] != '\0';
+}
+
+inline float_column convert_column_to_float(float_column v) { return v; }
+inline float_column convert_column_to_float(int_column v) { return v; }
+inline float_column convert_column_to_float(bool_column v) { return v; }
+inline float_column convert_column_to_float(text_column v)
+{
+ return std::atof(v->data);
+}
+
+inline text_column convert_column_to_text(float_column v)
+{
+ const int bufsize = 50;
+ RefCountString* str = RefCountString::allocate(bufsize);
+ snprintf(str->data, bufsize, "%g", v); // lgtm[cpp/badly-bounded-write]
+ return str;
+}
+inline text_column convert_column_to_text(int_column v)
+{
+ const int bufsize = (sizeof(int_column) * 8 + 1) / 3 + 1;
+ RefCountString* str = RefCountString::allocate(bufsize);
+ snprintf(str->data, bufsize, "%d", v); // lgtm[cpp/badly-bounded-write]
+ return str;
+}
+inline text_column convert_column_to_text(bool_column v)
+{
+ const int bufsize = 1 + 1;
+ RefCountString* str = RefCountString::allocate(bufsize);
+ if (v)
+ str->data[0] = '1';
+ else
+ str->data[1] = '0';
+ str->data[1] = '\0';
+ return str;
+}
+inline text_column convert_column_to_text(text_column v)
+{
+ // to stay symmetric with above functions that allocate a new string,
+ // increment reference count
+ v->inc_refcount();
+ return v;
+}
+
+// Variant represents a value that can be either one of the column types,
+// plus a type field to figure out which kind it represents
+class Variant {
+public:
+ Variant()
+ {
+ m_type = Coltype::_int;
+ m_val.m_int = 0;
+ }
+
+ Variant(bool_column val)
+ {
+ m_type = Coltype::_bool;
+ m_val.m_bool = val;
+ }
+
+ Variant(int_column val)
+ {
+ m_type = Coltype::_int;
+ m_val.m_int = val;
+ }
+
+ Variant(float_column val)
+ {
+ m_type = Coltype::_float;
+ m_val.m_float = val;
+ }
+
+ Variant(text_column val)
+ {
+ m_type = Coltype::_text;
+ m_val.m_text = val;
+ m_val.m_text->inc_refcount();
+ }
+
+ Variant(const Variant& other)
+ {
+ m_type = other.m_type;
+ m_val = other.m_val;
+ if (m_type == Coltype::_text)
+ m_val.m_text->inc_refcount();
+ }
+
+ // move constructor
+ Variant(Variant&& other)
+ {
+ // would be cleaner to use default constructor, but alas
+ // constructor delegation requires GCC >= 4.7
+ m_type = Coltype::_int;
+ m_val.m_int = 0;
+
+ swap(*this, other);
+ }
+
+ ~Variant()
+ {
+ if (m_type == Coltype::_text)
+ m_val.m_text->dec_refcount();
+ }
+
+ Variant& operator=(Variant other)
+ {
+ // copy and swap idiom
+ swap(*this, other);
+ return *this;
+ }
+
+ inline friend void swap(Variant& first, Variant& second)
+ {
+ using std::swap;
+ swap(first.m_type, second.m_type);
+ swap(first.m_val, second.m_val);
+ }
+
+ bool_column get_bool() const
+ {
+ switch (m_type) {
+ case Coltype::_float:
+ return convert_column_to_bool(m_val.m_float);
+ case Coltype::_int:
+ return convert_column_to_bool(m_val.m_int);
+ case Coltype::_bool:
+ return convert_column_to_bool(m_val.m_bool);
+ case Coltype::_text:
+ return convert_column_to_bool(m_val.m_text);
+ }
+ return false;
+ }
+
+ int_column get_int() const
+ {
+ switch (m_type) {
+ case Coltype::_float:
+ return convert_column_to_int(m_val.m_float);
+ case Coltype::_int:
+ return convert_column_to_int(m_val.m_int);
+ case Coltype::_bool:
+ return convert_column_to_int(m_val.m_bool);
+ case Coltype::_text:
+ return convert_column_to_int(m_val.m_text);
+ }
+ return 0;
+ }
+
+ float_column get_float() const
+ {
+ switch (m_type) {
+ case Coltype::_float:
+ return convert_column_to_float(m_val.m_float);
+ case Coltype::_int:
+ return convert_column_to_float(m_val.m_int);
+ case Coltype::_bool:
+ return convert_column_to_float(m_val.m_bool);
+ case Coltype::_text:
+ return convert_column_to_float(m_val.m_text);
+ }
+ return 0.0;
+ }
+
+ // this returns a RefCountString with the ref-count incremented so
+ // caller is responsible for decrementing after use
+ text_column get_text() const
+ {
+ switch (m_type) {
+ case Coltype::_float:
+ return convert_column_to_text(m_val.m_float);
+ case Coltype::_int:
+ return convert_column_to_text(m_val.m_int);
+ case Coltype::_bool:
+ return convert_column_to_text(m_val.m_bool);
+ case Coltype::_text:
+ return convert_column_to_text(m_val.m_text);
+ }
+ return RefCountString::construct("");
+ }
+
+ int cmp(const Variant& rhs) const
+ {
+ switch (m_type) {
+ case (Coltype::_bool):
+ return m_val.m_bool - rhs.get_bool();
+ case (Coltype::_int):
+ return m_val.m_int - rhs.get_int();
+ case (Coltype::_float): {
+ float_column r = rhs.get_float();
+ if (m_val.m_float < r)
+ return -1;
+ if (m_val.m_float > r)
+ return 1;
+ return 0;
+ }
+ case (Coltype::_text): {
+ RefCountString* s = rhs.get_text();
+ auto res = strcmp(m_val.m_text->data, s->data);
+ s->dec_refcount();
+ return res;
+ }
+ }
+ return 0;
+ }
+
+ bool operator<(const Variant& rhs) const
+ {
+ return cmp(rhs) < 0;
+ }
+ bool operator==(const Variant& rhs) const
+ {
+ return cmp(rhs) == 0;
+ }
+
+ std::size_t hash() const
+ {
+ switch (m_type) {
+ case (Coltype::_bool):
+ return std::hash<bool>()(m_val.m_bool);
+ case (Coltype::_int):
+ return std::hash<int>()(m_val.m_int);
+ case (Coltype::_float):
+ return std::hash<float>()(m_val.m_float);
+ case (Coltype::_text):
+ return hash_bytes(m_val.m_text->data, strlen(m_val.m_text->data));
+ }
+ return 0;
+ }
+
+ Coltype::Type m_type;
+
+private:
+ union VariantUnion {
+ bool_column m_bool;
+ int_column m_int;
+ float_column m_float;
+ text_column m_text;
+ };
+
+ VariantUnion m_val;
+};
+
+} // namespace packetq
+
+#endif // __packetq_variant_h
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