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-rw-r--r--src/lib/util/cstrpool.cpp114
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diff --git a/src/lib/util/cstrpool.cpp b/src/lib/util/cstrpool.cpp
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+// license:BSD-3-Clause
+// copyright-holders:Aaron Giles
+/***************************************************************************
+
+ cstrpool.c
+
+ Constant string pool helper class.
+
+***************************************************************************/
+
+#include <assert.h>
+
+#include "cstrpool.h"
+
+
+//**************************************************************************
+// CONST STRING POOL
+//**************************************************************************
+
+//-------------------------------------------------
+// const_string_pool - constructor
+//-------------------------------------------------
+
+const_string_pool::const_string_pool()
+{
+}
+
+
+//-------------------------------------------------
+// add - add a string to the string pool
+//-------------------------------------------------
+
+const char *const_string_pool::add(const char *string)
+{
+ // if NULL or a small number (for some hash strings), just return as-is
+ if (FPTR(string) < 0x100)
+ return string;
+
+ // scan to find space
+ for (pool_chunk *chunk = m_chunklist.first(); chunk != NULL; chunk = chunk->next())
+ {
+ const char *result = chunk->add(string);
+ if (result != NULL)
+ return result;
+ }
+
+ // no space anywhere, create a new pool and prepend it (so it gets used first)
+ const char *result = m_chunklist.prepend(*global_alloc(pool_chunk)).add(string);
+ assert(result != NULL);
+ return result;
+}
+
+
+//-------------------------------------------------
+// contains - determine if the given string
+// pointer lives in the pool
+//-------------------------------------------------
+
+bool const_string_pool::contains(const char *string)
+{
+ // if NULL or a small number (for some hash strings), then yes, effectively
+ if (FPTR(string) < 0x100)
+ return true;
+
+ // scan to find it
+ for (pool_chunk *chunk = m_chunklist.first(); chunk != NULL; chunk = chunk->next())
+ if (chunk->contains(string))
+ return true;
+
+ return false;
+}
+
+/**
+ * @fn const_string_pool::pool_chunk::pool_chunk()
+ *
+ * @brief -------------------------------------------------
+ * pool_chunk - constructor
+ * -------------------------------------------------.
+ */
+
+const_string_pool::pool_chunk::pool_chunk()
+ : m_next(NULL),
+ m_used(0)
+{
+}
+
+/**
+ * @fn const char *const_string_pool::pool_chunk::add(const char *string)
+ *
+ * @brief -------------------------------------------------
+ * add - add a string to this pool
+ * -------------------------------------------------.
+ *
+ * @param string The string to add.
+ *
+ * @return null if it fails, else a char*.
+ */
+
+const char *const_string_pool::pool_chunk::add(const char *string)
+{
+ // get the length of the string (no string can be longer than a full pool)
+ int bytes = strlen(string) + 1;
+ assert(bytes < POOL_SIZE);
+
+ // if too big, return NULL
+ if (m_used + bytes > POOL_SIZE)
+ return NULL;
+
+ // allocate, copy, and return the memory
+ char *dest = &m_buffer[m_used];
+ m_used += bytes;
+ memcpy(dest, string, bytes);
+ return dest;
+}