--- /dev/null
+/*****************************************************************************/
+/* */
+/* strpool.c */
+/* */
+/* A string pool */
+/* */
+/* */
+/* */
+/* (C) 2003 Ullrich von Bassewitz */
+/* Römerstrasse 52 */
+/* D-70794 Filderstadt */
+/* EMail: uz@cc65.org */
+/* */
+/* */
+/* This software is provided 'as-is', without any expressed or implied */
+/* warranty. In no event will the authors be held liable for any damages */
+/* arising from the use of this software. */
+/* */
+/* Permission is granted to anyone to use this software for any purpose, */
+/* including commercial applications, and to alter it and redistribute it */
+/* freely, subject to the following restrictions: */
+/* */
+/* 1. The origin of this software must not be misrepresented; you must not */
+/* claim that you wrote the original software. If you use this software */
+/* in a product, an acknowledgment in the product documentation would be */
+/* appreciated but is not required. */
+/* 2. Altered source versions must be plainly marked as such, and must not */
+/* be misrepresented as being the original software. */
+/* 3. This notice may not be removed or altered from any source */
+/* distribution. */
+/* */
+/*****************************************************************************/
+
+
+
+/* A string pool is used to store identifiers and other strings. Each string
+ * stored in the pool has a unique id, which may be used to access the string
+ * in the pool. Identical strings are only stored once in the pool and have
+ * identical ids. This means that instead of comparing strings, just the
+ * string pool ids must be compared.
+ */
+
+
+
+#include <string.h>
+
+/* common */
+#include "coll.h"
+#include "hashstr.h"
+#include "strbuf.h"
+#include "strpool.h"
+#include "xmalloc.h"
+
+
+
+/*****************************************************************************/
+/* Data */
+/*****************************************************************************/
+
+
+
+/* A string pool entry */
+struct StrPoolEntry {
+ StrPoolEntry* Next; /* Pointer to next entry in hash chain */
+ unsigned Hash; /* Full hash value */
+ unsigned Id; /* The numeric string id */
+ unsigned Len; /* Length of the string (excluding terminator) */
+ char S[1]; /* The string itself */
+};
+
+
+
+/*****************************************************************************/
+/* struct StrPoolEntry */
+/*****************************************************************************/
+
+
+
+static StrPoolEntry* NewStrPoolEntry (const char* S, unsigned Hash, unsigned Id)
+/* Create a new string pool entry and return it. */
+{
+ /* Get the length of the string */
+ unsigned Len = strlen (S);
+
+ /* Allocate memory */
+ StrPoolEntry* E = xmalloc (sizeof (StrPoolEntry) + Len);
+
+ /* Initialize the fields */
+ E->Next = 0;
+ E->Hash = Hash;
+ E->Id = Id;
+ E->Len = Len;
+ memcpy (E->S, S, Len+1);
+
+ /* Return the new entry */
+ return E;
+}
+
+
+
+/*****************************************************************************/
+/* Code */
+/*****************************************************************************/
+
+
+
+StrPool* InitStrPool (StrPool* P)
+/* Initialize a string pool */
+{
+ unsigned I;
+
+ /* Initialize the fields */
+ for (I = 0; I < sizeof (P->Tab) / sizeof (P->Tab[0]); ++I) {
+ P->Tab[I] = 0;
+ }
+ P->Entries = EmptyCollection;
+ P->TotalSize = 0;
+
+ /* Return a pointer to the initialized pool */
+ return P;
+}
+
+
+
+void DoneStrPool (StrPool* P)
+/* Free the data of a string pool (but not the data itself) */
+{
+ unsigned I;
+
+ /* Free all entries and clear the entry collection */
+ for (I = 0; I < CollCount (&P->Entries); ++I) {
+ xfree (CollAtUnchecked (&P->Entries, I));
+ }
+ CollDeleteAll (&P->Entries);
+
+ /* Clear the hash table */
+ for (I = 0; I < sizeof (P->Tab) / sizeof (P->Tab[0]); ++I) {
+ P->Tab[I] = 0;
+ }
+
+ /* Reset the size */
+ P->TotalSize = 0;
+}
+
+
+
+StrPool* NewStrPool (void)
+/* Allocate, initialize and return a new string pool */
+{
+ /* Allocate memory, initialize and return it */
+ return InitStrPool (xmalloc (sizeof (StrPool)));
+}
+
+
+
+void FreeStrPool (StrPool* P)
+/* Free a string pool */
+{
+ /* Free all entries */
+ DoneStrPool (P);
+
+ /* Free the string pool itself */
+ xfree (P);
+}
+
+
+
+const char* SP_Get (const StrPool* P, unsigned Index)
+/* Return a string from the pool. Index must exist, otherwise FAIL is called. */
+{
+ /* Get the collection entry */
+ const StrPoolEntry* E = CollConstAt (&P->Entries, Index);
+
+ /* Return the string from the entry */
+ return E->S;
+}
+
+
+
+unsigned SP_Add (StrPool* P, const char* S)
+/* Add a string to the buffer and return the index. If the string does already
+ * exist in the pool, SP_Add will just return the index of the existing string.
+ */
+{
+ /* Calculate the string hash */
+ unsigned Hash = HashStr (S);
+
+ /* Calculate the reduced string hash */
+ unsigned RHash = Hash % (sizeof (P->Tab)/sizeof (P->Tab[0]));
+
+ /* Search for an existing entry */
+ StrPoolEntry* E = P->Tab[RHash];
+ while (E) {
+ if (E->Hash == Hash && strcmp (E->S, S) == 0) {
+ /* Found, return the id of the existing string */
+ return E->Id;
+ }
+ E = E->Next;
+ }
+
+ /* We didn't find the entry, so create a new one */
+ E = NewStrPoolEntry (S, Hash, CollCount (&P->Entries));
+
+ /* Insert the new entry into the entry collection */
+ CollAppend (&P->Entries, E);
+
+ /* Insert the new entry into the hash table */
+ E->Next = P->Tab[RHash];
+ P->Tab[RHash] = E;
+
+ /* Add up the string size (plus terminator) */
+ P->TotalSize += E->Len + 1;
+
+ /* Return the id of the entry */
+ return E->Id;
+}
+
+
+
+unsigned SP_AddBuf (StrPool* P, const void* Buffer, unsigned Size)
+/* Add strings from a string buffer. Buffer must contain a list of zero
+ * terminated strings. These strings are added to the pool, starting with
+ * the current index. The number of strings added is returned.
+ * Beware: The function will do only loose range checking for the buffer
+ * limits, so a SEGV may occur if the last string in the buffer is not
+ * correctly terminated.
+ */
+{
+ /* Cast the buffer pointer to something useful */
+ const char* Buf = Buffer;
+
+ /* Remember the current number of strings in the buffer. */
+ unsigned OldCount = SB_GetCount (P);
+
+ /* Add all strings from the buffer */
+ while (Size) {
+
+ /* Add the next entry */
+ unsigned Id = SP_Add (P, Buf);
+
+ /* Get the entry from the id */
+ const StrPoolEntry* E = CollConstAt (&P->Entries, Id);
+
+ /* Skip this string */
+ Buf += E->Len + 1;
+ Size -= E->Len + 1;
+ }
+
+ /* Return the number of strings added */
+ return SB_GetCount (P) - OldCount;
+}
+
+
+
+void SP_Build (StrPool* P, const void* Buffer, unsigned Size)
+/* Delete existing data and use the data from Buffer instead. */
+{
+ /* Delete old data */
+ DoneStrPool (P);
+
+ /* Add the buffer data */
+ SP_AddBuf (P, Buffer, Size);
+}
+
+
+
--- /dev/null
+/*****************************************************************************/
+/* */
+/* strpool.h */
+/* */
+/* A string pool */
+/* */
+/* */
+/* */
+/* (C) 2003 Ullrich von Bassewitz */
+/* Römerstrasse 52 */
+/* D-70794 Filderstadt */
+/* EMail: uz@cc65.org */
+/* */
+/* */
+/* This software is provided 'as-is', without any expressed or implied */
+/* warranty. In no event will the authors be held liable for any damages */
+/* arising from the use of this software. */
+/* */
+/* Permission is granted to anyone to use this software for any purpose, */
+/* including commercial applications, and to alter it and redistribute it */
+/* freely, subject to the following restrictions: */
+/* */
+/* 1. The origin of this software must not be misrepresented; you must not */
+/* claim that you wrote the original software. If you use this software */
+/* in a product, an acknowledgment in the product documentation would be */
+/* appreciated but is not required. */
+/* 2. Altered source versions must be plainly marked as such, and must not */
+/* be misrepresented as being the original software. */
+/* 3. This notice may not be removed or altered from any source */
+/* distribution. */
+/* */
+/*****************************************************************************/
+
+
+
+/* A string pool is used to store identifiers and other strings. Each string
+ * stored in the pool has a unique id, which may be used to access the string
+ * in the pool. Identical strings are only stored once in the pool and have
+ * identical ids. This means that instead of comparing strings, just the
+ * string pool ids must be compared.
+ */
+
+
+
+#ifndef STRPOOL_H
+#define STRPOOL_H
+
+
+
+/* common */
+#include "coll.h"
+#include "inline.h"
+#include "strbuf.h"
+
+
+
+/*****************************************************************************/
+/* Data */
+/*****************************************************************************/
+
+
+
+/* Opaque entry */
+typedef struct StrPoolEntry StrPoolEntry;
+
+typedef struct StrPool StrPool;
+struct StrPool {
+ StrPoolEntry* Tab[211]; /* Entry hash table */
+ Collection Entries; /* Entries sorted by number */
+ unsigned TotalSize; /* Total size of all string data */
+};
+
+
+
+/*****************************************************************************/
+/* Code */
+/*****************************************************************************/
+
+
+
+StrPool* InitStrPool (StrPool* P);
+/* Initialize a string pool */
+
+void DoneStrPool (StrPool* P);
+/* Free the data of a string pool (but not the data itself) */
+
+StrPool* NewStrPool (void);
+/* Allocate, initialize and return a new string pool */
+
+void FreeStrPool (StrPool* P);
+/* Free a string pool */
+
+void SP_Use (char* Buffer, unsigned Size);
+/* Delete existing data and use the data from Buffer instead. Buffer must be
+ * allocated on the heap and will be freed using xfree() if necessary.
+ */
+
+const char* SP_Get (const StrPool* P, unsigned Index);
+/* Return a string from the pool. Index must exist, otherwise FAIL is called. */
+
+unsigned SP_Add (StrPool* P, const char* S);
+/* Add a string to the buffer and return the index. If the string does already
+ * exist in the pool, SP_Add will just return the index of the existing string.
+ */
+
+#if defined(HAVE_INLINE)
+INLINE unsigned SB_GetCount (const StrPool* P)
+/* Return the number of strings in the pool */
+{
+ return CollCount (&P->Entries);
+}
+#else
+# define SB_GetCount(P) CollCount (&(P)->Entries)
+#endif
+
+
+
+/* End of strpool.h */
+
+#endif
+
+
+
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