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authorDaniel Baumann <daniel@debian.org>2024-11-21 15:51:37 +0100
committerDaniel Baumann <daniel@debian.org>2024-11-21 15:51:37 +0100
commitebb64aabedd789b5affbf30f03e43fcf3a0561f4 (patch)
treeec4dd9937434be85039f900efcc48c75c182d81d /src/refcountstring.h
parentInitial commit. (diff)
downloadpacketq-upstream.tar.xz
packetq-upstream.zip
Adding upstream version 1.7.3+dfsg.upstream/1.7.3+dfsgupstream
Signed-off-by: Daniel Baumann <daniel@debian.org>
Diffstat (limited to 'src/refcountstring.h')
-rw-r--r--src/refcountstring.h122
1 files changed, 122 insertions, 0 deletions
diff --git a/src/refcountstring.h b/src/refcountstring.h
new file mode 100644
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+++ b/src/refcountstring.h
@@ -0,0 +1,122 @@
+/*
+ * 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_refcountstring_h
+#define __packetq_refcountstring_h
+
+#include <cstdlib>
+#include <cstring>
+
+// A simple reference-counted C string, intended to be used through a pointer
+// as RefCountString * with manual management of the reference count in order
+// to stay a POD (for use in unions). For the same reason, constructors are
+// static. The wrapper RefCountStringHandle can be used where automatic
+// reference handling is possible.
+struct RefCountString {
+ // data
+ int count;
+ char data[];
+
+ // implementation
+ void inc_refcount()
+ {
+ count += 1;
+ }
+
+ void dec_refcount()
+ {
+ count -= 1;
+ if (count == 0)
+ std::free(this);
+ }
+
+ static RefCountString* allocate(int data_length)
+ {
+ void* chunk = std::calloc(1, sizeof(RefCountString) + data_length);
+ if (!chunk)
+ throw std::bad_alloc();
+
+ RefCountString* new_str = static_cast<RefCountString*>(chunk);
+ new_str->count = 1;
+ return new_str;
+ }
+
+ static RefCountString* construct(const char* c_string)
+ {
+ std::size_t length = std::strlen(c_string);
+ RefCountString* str = RefCountString::allocate(length + 1);
+ std::memcpy(str->data, c_string, length + 1);
+ return str;
+ }
+
+ static RefCountString* construct(const char* data, int from, int to)
+ {
+ int length = to - from;
+ if (length < 0)
+ length = 0;
+ RefCountString* str = RefCountString::allocate(length + 1);
+ std::memcpy(str->data, data + from, length);
+ str->data[length - 1 + 1] = '\0';
+ return str;
+ }
+};
+
+class RefCountStringHandle {
+private:
+ RefCountStringHandle& operator=(const RefCountStringHandle& other);
+ RefCountStringHandle(RefCountStringHandle&& other) noexcept;
+ RefCountStringHandle const& operator=(RefCountStringHandle&& other);
+
+public:
+ RefCountStringHandle()
+ {
+ value = 0;
+ }
+
+ RefCountStringHandle(RefCountString* str)
+ {
+ value = str;
+ }
+
+ ~RefCountStringHandle()
+ {
+ if (value)
+ value->dec_refcount();
+ }
+
+ RefCountString* operator*()
+ {
+ return value;
+ }
+
+ void set(RefCountString* str)
+ {
+ if (value != str) {
+ if (value)
+ value->dec_refcount();
+ value = str;
+ }
+ }
+
+ RefCountString* value;
+};
+
+#endif // __packetq_refcountstring_h