/** @file * IPRT - Abstract Table/Trees. */ /* * Copyright (C) 2006-2016 Oracle Corporation * * This file is part of VirtualBox Open Source Edition (OSE), as * available from http://www.virtualbox.org. This file is free software; * you can redistribute it and/or modify it under the terms of the GNU * General Public License (GPL) as published by the Free Software * Foundation, in version 2 as it comes in the "COPYING" file of the * VirtualBox OSE distribution. VirtualBox OSE is distributed in the * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind. * * The contents of this file may alternatively be used under the terms * of the Common Development and Distribution License Version 1.0 * (CDDL) only, as it comes in the "COPYING.CDDL" file of the * VirtualBox OSE distribution, in which case the provisions of the * CDDL are applicable instead of those of the GPL. * * You may elect to license modified versions of this file under the * terms and conditions of either the GPL or the CDDL or both. */ #ifndef ___iprt_table_h #define ___iprt_table_h #include /** @defgroup grp_rt_tab RTTab - Generic Tree and Table Interface. * @ingroup grp_rt * @{ */ RT_C_DECLS_BEGIN /** Pointer to an allocator. */ typedef struct RTTABALLOCATOR *PRTTABALLOCATOR; /** * Allocates memory. * * @returns Pointer to the allocated memory. * @returns NULL on failure. (don't throw!) * @param pAllocator The allocator structure. * @param cb The number of bytes to allocate. (Never 0.) */ typedef DECLCALLBACK(void *) FNRTTABALLOC(PRTTABALLOCATOR pAllocator, size_t cb); /** Pointer to a FNRTTABALLOC() function. */ typedef FNRTTABALLOC *PFNRTTABALLOC; /** * Frees memory. * * @param pAllocator The allocator structure. * @param pv The memory to free. (can be NULL) */ typedef DECLCALLBACK(void *) FNRTTABFREE(PRTTABALLOCATOR pAllocator, void *pv); /** Pointer to a FNRTTABFREE() function. */ typedef FNRTTABFREE *PFNRTTABFREE; /** * The allocator structure. * (Hint: use this as like 'base class' for your custom allocators.) */ typedef struct RTTABALLOCATOR { /** The allocation function. */ PFNRTTABALLOC pfnAlloc; /** The free function. */ PFNRTTABFREE pfnFree; } RTTABALLOCATOR; /** * Gets the default allocator. * * @returns Pointer to the default allocator. */ RTDECL(RTTABALLOCATOR) RTTabDefaultAllocator(void); /** * Compares two table items. * * @returns 0 if equal * @returns <0 if pvItem1 is less than pvItem2 (pvItem2 is then greater than pvItem1). * @returns >0 if pvItem1 is less than pvItem2 (pvItem1 is then greater than pvItem2). * * @param pvItem1 The first item. * @param pvItem2 The second item. * @param pvUser The user argument. */ typedef DECLCALLBACK(int) FNRTTABCOMP(const void *pvItem1, const void *pvItem2, void *pvUser); /** Pointer to a FNRTTABCOMP() function. */ typedef FNRTTABCOMP *PFNRTTABCOMP; /** * Duplicates a table item. * This is used when duplicating or copying a table. * * @returns Pointer to the copy. * @returns NULL on failure. * * @param pvItem The item to copy. * @param pvUser The user argument. */ typedef DECLCALLBACK(void *) FNRTTABDUPLICATE(const void *pvItem, void *pvUser); /** Pointer to a FNRTTABDUPLICATE() function. */ typedef FNRTTABDUPLICATE *PFNRTTABDUPLICATE; /** * Callback function for doing something with an item. * * What exactly we're doing is specific to the context of the call. * * @param pvItem The item. * @param pvUser The user argument. */ typedef DECLCALLBACK(void) FNRTTABCALLBACK(const void *pvItem, void *pvUser); /** Pointer to a FNRTTABCALLBACK() function. */ typedef FNRTTABCALLBACK *PFNRTTABCALLBACK; /** Pointer to const table operations. */ typedef const struct RTTABOPS *PCRTTABOPS; /** Pointer to a table. */ typedef struct RTTAB *PRTTAB; /** Pointer to a const table. */ typedef const struct RTTAB *PCRTTAB; /** Pointer to a traverser. */ typedef struct RTTABTRAVERSER *PRTTABTRAVERSER; /** Pointer to a const traverser. */ typedef const struct RTTABTRAVERSER *PCRTTABTRAVERSER; /** Pointer to a traverser core. */ typedef struct RTTABTRAVERSERCORE *PRTTABTRAVERSERCORE; /** Pointer to a const traverser core. */ typedef const struct RTTABTRAVERSERCORE *PCRTTABTRAVERSERCORE; /** * Table operations. */ typedef struct RTTABOPS { /** * Create a table. * * @returns Pointer to the new table. * @returns NULL if we're out of memory or some other resource. * @param pOps The table operations. * @param fCreateFlags The table type specific creation flags. * @param pAllocator Custom allocator. Pass NULL for the default allocator. * @param pfnComp The comparision function. */ DECLCALLBACKMEMBER(PRTTAB, pfnCreate)(PCRTTABOPS pOps, unsigned fCreateFlags, PRTTABALLOCATOR pAllocator, PFNRTTABCOMP pfnComp); /** * Duplicates a table to a table of the same type. * * @returns Pointer to the new table. * @returns NULL if we're out of memory or some other resource. * @param pTab The table to duplicate. * @param pfnDuplicate Pointer to the item duplication function. If NULL the new table will * be referencing the same data as the old one. * @param pfnNewCB Callback which is called for all the items in the new table. Optional. * @param pAllocator Custom allocator. Pass NULL to use the same allocator as pTab. */ DECLCALLBACKMEMBER(PRTTAB, pfnDuplicate)(PCRTTAB pTab, PFNRTTABDUPLICATE pfnDuplicate, PFNRTTABCALLBACK pfnNewCB, PRTTABALLOCATOR pAllocator); /** * Destroys a table. * * @param pTab The table to destroy. */ DECLCALLBACKMEMBER(void, pfnDestroy)(PRTTAB pTab); /** * Inserts an item into the table, if a matching item is encountered * the pointer to the pointer to it will be returned. * * @returns Pointer to the item pointer in the table. * This can be used to replace existing items (don't break anything, dude). * @returns NULL if we failed to allocate memory for the new node. * @param pTab The table. * @param pvItem The item which will be inserted if an matching item was not found in the table. */ DECLCALLBACKMEMBER(void **, pfnProbe)(PRTTAB pTab, void *pvItem); /** * Inserts an item into the table, fail if a matching item exists. * * @returns NULL on success and allocation failure. * @returns Pointer to the matching item. * @param pTab The table. * @param pvItem The item which is to be inserted. */ DECLCALLBACKMEMBER(void *, pfnInsert)(PRTTAB pTab, void *pvItem); /** * Inserts an item into the table, if a matching item is encountered * it will be replaced and returned. * * @returns NULL if inserted and allocation failure. * @returns Pointer to the replaced item. * @param pTab The table. * @param pvItem The item which is to be inserted. */ DECLCALLBACKMEMBER(void *, pfnReplace)(PRTTAB pTab, void *pvItem); /** * Removes an item from the table if found. * * @returns Pointer to the removed item. * @returns NULL if no item matched pvItem. * @param pTab The table. * @param pvItem The item which is to be inserted. */ DECLCALLBACKMEMBER(void *, pfnRemove)(PRTTAB pTab, const void *pvItem); /** * Finds an item in the table. * * @returns Pointer to the item it found. * @returns NULL if no item matched pvItem. * @param pTab The table. * @param pvItem The item which is to be inserted. */ DECLCALLBACKMEMBER(void *, pfnFind)(PRTTAB pTab, const void *pvItem); /** * Initializes a traverser to the NULL item. * * The NULL item is an imaginary table item before the first and after * the last items in the table. * * @returns Pointer to the traverser positioned at the NULL item. * @returns NULL on failure to allocate the traverser. * * @param pTab The table. * @param pTravNew Pointer to a preallocated structure. Optional. */ DECLCALLBACKMEMBER(PRTTABTRAVERSERCORE, pfnTravInit)(PRTTAB pTab, PRTTABTRAVERSER pTravNew); /** * Initializes a traverser to the first item in the table. * * If the table is empty, the traverser will be positioned at the NULL item * like with RTTabTravInit(). * * @returns Pointer to the traverser positioned at the first item or NULL item. * @returns NULL on failure to allocate the traverser. * * @param pTab The table. * @param pTravNew Pointer to a preallocated structure. Optional. */ DECLCALLBACKMEMBER(PRTTABTRAVERSERCORE, pfnTravFirst)(PRTTAB pTab, PRTTABTRAVERSER pTravNew); /** * Initializes a traverser to the last item in the table. * * If the table is empty, the traverser will be positioned at the NULL item * like with RTTabTravInit(). * * @returns Pointer to the traverser positioned at the last item or NULL item. * @returns NULL on failure to allocate the traverser. * * @param pTab The table. * @param pTravNew Pointer to a preallocated structure. Optional. */ DECLCALLBACKMEMBER(PRTTABTRAVERSERCORE, pfnTravLast)(PRTTAB pTab, PRTTABTRAVERSER pTravNew); /** * Initializes a traverser to an item matching the given one. * * If the item isn't found, the traverser will be positioned at the NULL item * like with RTTabTravInit(). * * @returns Pointer to the traverser positioned at the matching item or NULL item. * @returns NULL on failure to allocate the traverser. * * @param pTab The table. * @param pTravNew Pointer to a preallocated structure. Optional. * @param pvItem The item to find the match to. */ DECLCALLBACKMEMBER(PRTTABTRAVERSERCORE, pfnTravFind)(PRTTAB pTab, PRTTABTRAVERSER pTravNew, const void *pvItem); /** * Initializes a traverser to the inserted item. * * If there already exists an item in the tree matching pvItem, the traverser * is positioned at that item like with RTTabTravFind(). * * If the insert operation failes because of an out of memory condition, the * traverser will be positioned at the NULL item like with RTTabTravInit(). * * @returns Pointer to the traverser positioned at the inserted, existing or NULL item. * @returns NULL on failure to allocate the traverser. * * @param pTab The table. * @param pTravNew Pointer to a preallocated structure. Optional. * @param pvItem The item to be inserted. */ DECLCALLBACKMEMBER(PRTTABTRAVERSERCORE, pfnTravInsert)(PRTTAB pTab, PRTTABTRAVERSER pTravNew, void *pvItem); /** * Duplicates a traverser. * * @returns The pointer to the duplicate. * @returns NULL on allocation failure. * * @param pTrav The traverser to duplicate. * @param pTravNew Pointer to a preallocated structure. Optional. */ DECLCALLBACKMEMBER(PRTTABTRAVERSERCORE, pfnTravDuplicate)(PRTTABTRAVERSERCORE pTrav, PCRTTABTRAVERSER pTravNew); /** * Frees a traverser. * * This can safely be called even if the traverser structure * wasn't dynamically allocated or the constructor failed. * * @param pTrav The traverser which is to be free. */ DECLCALLBACKMEMBER(void, pfnTravFree)(PRTTABTRAVERSERCORE pTrav); /** * Gets the current item. * * @returns The current item. (NULL indicates the imaginary NULL item.) * @param pTrav The traverser. */ DECLCALLBACKMEMBER(void *, pfnTravCur)(PCRTTABTRAVERSERCORE pTrav); /** * Advances to the next item. * * @returns The new current item. (NULL indicates the imaginary NULL item.) * @param pTrav The traverser. */ DECLCALLBACKMEMBER(void *, pfnTravNext)(PRTTABTRAVERSERCORE pTrav); /** * Advances to the previous item. * * @returns The new current item. (NULL indicates the imaginary NULL item.) * @param pTrav The traverser. */ DECLCALLBACKMEMBER(void *, pfnTravPrev)(PRTTABTRAVERSERCORE pTrav); /** * Replaces the current item. * * This has the same restrictions as RTTabProbe(), e.g. it's not permitted to * break the order of the table. * * @returns The replaced item. * @returns NULL if the current item is the NULL item. The traverser * and table remains unchanged. * @param pTrav The traverser. * @param pvItem The item to be inserted. */ DECLCALLBACKMEMBER(void *, pfnTravReplace)(PRTTABTRAVERSERCORE pTrav, void *pvItem); /** The type of table type. */ const char *pszType; } RTTABOPS; /** * A table. */ typedef struct RTTAB { /** The table operations. */ PCRTTABOPS pOps; /** The function for comparing table items. */ PFNRTTABCOMP pfnComp; /** The number of items in the table. */ RTUINT cItems; /** The table generation number. * This must be updated whenever the table changes. */ RTUINT idGeneration; } RTTAB; /** * Create a table. * * @returns Pointer to the new table. * @returns NULL if we're out of memory or some other resource. * @param pOps The table operations. * @param fCreateFlags The table type specific creation flags. * @param pAllocator Custom allocator. Pass NULL for the default allocator. * @param pfnComp The comparision function. */ DECLINLINE(PRTTAB) RTTabCreate(PCRTTABOPS pOps, unsigned fCreateFlags, PRTTABALLOCATOR pAllocator, PFNRTTABCOMP pfnComp) { return pOps->pfnCreate(pOps, fCreateFlags, pAllocator, pfnComp); } /** * Duplicates a table to a table of the same type. * * @returns Pointer to the new table. * @returns NULL if we're out of memory or some other resource. * @param pTab The table to duplicate. * @param pfnDuplicate Pointer to the item duplication function. If NULL the new table will * be referencing the same data as the old one. * @param pfnNewCB Callback which is called for all the items in the new table. Optional. * @param pAllocator Custom allocator. Pass NULL to use the same allocator as pTab. */ DECLINLINE(PRTTAB) RTTabDuplicate(PCRTTAB pTab, PFNRTTABDUPLICATE pfnDuplicate, PFNRTTABCALLBACK pfnNewCB, PRTTABALLOCATOR pAllocator) { return pTab->pOps->pfnDuplicate(pTab, pfnDuplicate, pfnNewCB, pAllocator); } /** * Destroys a table. * * @param pTab The table to destroy. */ DECLINLINE(void) RTTabDestroy(PRTTAB pTab) { pTab->pOps->pfnDestroy(pTab); } /** * Count the item in the table. * * @returns Number of items in the table. * @param pTab The table to count. */ DECLINLINE(RTUINT) RTTabCount(PRTTAB pTab) { return pTab->cItems; } /** * Inserts an item into the table, if a matching item is encountered * the pointer to the pointer to it will be returned. * * @returns Pointer to the item pointer in the table. * This can be used to replace existing items (don't break anything, dude). * @returns NULL if we failed to allocate memory for the new node. * @param pTab The table. * @param pvItem The item which will be inserted if an matching item was not found in the table. */ DECLINLINE(void **) RTTabProbe(PRTTAB pTab, void *pvItem) { return pTab->pOps->pfnProbe(pTab, pvItem); } /** * Inserts an item into the table, fail if a matching item exists. * * @returns NULL on success and allocation failure. * @returns Pointer to the matching item. * @param pTab The table. * @param pvItem The item which is to be inserted. */ DECLINLINE(void *) RTTabInsert(PRTTAB pTab, void *pvItem) { return pTab->pOps->pfnInsert(pTab, pvItem); } /** * Inserts an item into the table, if a matching item is encountered * it will be replaced and returned. * * @returns NULL if inserted and allocation failure. * @returns Pointer to the replaced item. * @param pTab The table. * @param pvItem The item which is to be inserted. */ DECLINLINE(void *) RTTabReplace(PRTTAB pTab, void *pvItem) { return pTab->pOps->pfnReplace(pTab, pvItem); } /** * Removes an item from the table if found. * * @returns Pointer to the removed item. * @returns NULL if no item matched pvItem. * @param pTab The table. * @param pvItem The item which is to be inserted. */ DECLINLINE(void *) RTTabRemove(PRTTAB pTab, const void *pvItem) { return pTab->pOps->pfnRemove(pTab, pvItem); } /** * Finds an item in the table. * * @returns Pointer to the item it found. * @returns NULL if no item matched pvItem. * @param pTab The table. * @param pvItem The item to find the match to. */ DECLINLINE(void *) RTTabFind(PRTTAB pTab, const void *pvItem) { return pTab->pOps->pfnFind(pTab, pvItem); } /** * Common traverser core. */ typedef struct RTTABTRAVERSERCORE { /** The table being traversed. */ PRTTAB pTab; /** Indicates that this traverser was allocated. */ bool fAllocated; /** The table generation id this traverser was last updated for. * This is used to catch up with table changes. */ RTUINT idGeneration; } RTTABTRAVERSERCORE; /** * Generic traverser structure. * * Tree implementations will use the tree specific part by mapping * this structure onto their own internal traverser structure. * * @remark It would be better to use alloca() for allocating the structure, * OTOH this is simpler for the user. */ typedef struct RTTABTRAVERSER { /** The common core of the traverser data. */ RTTABTRAVERSERCORE Core; /** The tree specific data. */ void *apvTreeSpecific[32]; } RTTABTRAVERSER; /** * Initializes a traverser to the NULL item. * * The NULL item is an imaginary table item before the first and after * the last items in the table. * * @returns Pointer to the traverser positioned at the NULL item. * @returns NULL on failure to allocate the traverser. * * @param pTab The table. * @param pTravNew Pointer to a preallocated structure. Optional. */ DECLINLINE(PRTTABTRAVERSERCORE) RTTabTravInit(PRTTAB pTab, PRTTABTRAVERSER pTravNew) { return pTab->pOps->pfnTravInit(pTab, pTravNew); } /** * Initializes a traverser to the first item in the table. * * If the table is empty, the traverser will be positioned at the NULL item * like with RTTabTravInit(). * * @returns Pointer to the traverser positioned at the first item or NULL item. * @returns NULL on failure to allocate the traverser. * * @param pTab The table. * @param pTravNew Pointer to a preallocated structure. Optional. */ DECLINLINE(PRTTABTRAVERSERCORE) RTTabTravFirst(PRTTAB pTab, PRTTABTRAVERSER pTravNew) { return pTab->pOps->pfnTravFirst(pTab, pTravNew); } /** * Initializes a traverser to the last item in the table. * * If the table is empty, the traverser will be positioned at the NULL item * like with RTTabTravInit(). * * @returns Pointer to the traverser positioned at the last item or NULL item. * @returns NULL on failure to allocate the traverser. * * @param pTab The table. * @param pTravNew Pointer to a preallocated structure. Optional. */ DECLINLINE(PRTTABTRAVERSERCORE) RTTabTravLast(PRTTAB pTab, PRTTABTRAVERSER pTravNew) { return pTab->pOps->pfnTravLast(pTab, pTravNew); } /** * Initializes a traverser to an item matching the given one. * * If the item isn't found, the traverser will be positioned at the NULL item * like with RTTabTravInit(). * * @returns Pointer to the traverser positioned at the matching item or NULL item. * @returns NULL on failure to allocate the traverser. * * @param pTab The table. * @param pTravNew Pointer to a preallocated structure. Optional. * @param pvItem The item to find the match to. */ DECLINLINE(PRTTABTRAVERSERCORE) RTTabTravFind(PRTTAB pTab, PRTTABTRAVERSER pTravNew, const void *pvItem) { return pTab->pOps->pfnTravFind(pTab, pTravNew, pvItem); } /** * Initializes a traverser to the inserted item. * * If there already exists an item in the tree matching pvItem, the traverser * is positioned at that item like with RTTabTravFind(). * * If the insert operation failes because of an out of memory condition, the * traverser will be positioned at the NULL item like with RTTabTravInit(). * * @returns Pointer to the traverser positioned at the inserted, existing or NULL item. * @returns NULL on failure to allocate the traverser. * * @param pTab The table. * @param pTravNew Pointer to a preallocated structure. Optional. * @param pvItem The item to be inserted. */ DECLINLINE(PRTTABTRAVERSERCORE) RTTabTravInsert(PRTTAB pTab, PRTTABTRAVERSER pTravNew, void *pvItem) { return pTab->pOps->pfnTravInsert(pTab, pTravNew, pvItem); } /** * Duplicates a traverser. * * @returns The pointer to the duplicate. * @returns NULL on allocation failure. * * @param pTrav The traverser to duplicate. * @param pTravNew Pointer to a preallocated structure. Optional. */ DECLINLINE(PRTTABTRAVERSERCORE) RTTabTravDuplicate(PRTTABTRAVERSERCORE pTrav, PCRTTABTRAVERSER pTravNew) { if (pTrav) return pTrav->pTab->pOps->pfnTravDuplicate(pTrav, pTravNew); return NULL; } /** * Frees a traverser. * * This can safely be called even if the traverser structure * wasn't dynamically allocated or the constructor failed. * * @param pTrav The traverser which is to be free. */ DECLINLINE(void) RTTabTravFree(PRTTABTRAVERSERCORE pTrav) { if (pTrav && pTrav->fAllocated) pTrav->pTab->pOps->pfnTravFree(pTrav); } /** * Gets the current item. * * @returns The current item. (NULL indicates the imaginary NULL item.) * @param pTrav The traverser. */ DECLINLINE(void *) RTTabTravCur(PCRTTABTRAVERSERCORE pTrav) { return pTrav->pTab->pOps->pfnTravCur(pTrav); } /** * Advances to the next item. * * @returns The new current item. (NULL indicates the imaginary NULL item.) * @param pTrav The traverser. */ DECLINLINE(void *) RTTabTravNext(PRTTABTRAVERSERCORE pTrav) { return pTrav->pTab->pOps->pfnTravNext(pTrav); } /** * Advances to the previous item. * * @returns The new current item. (NULL indicates the imaginary NULL item.) * @param pTrav The traverser. */ DECLINLINE(void *) RTTabTravPrev(PRTTABTRAVERSERCORE pTrav) { return pTrav->pTab->pOps->pfnTravPrev(pTrav); } /** * Replaces the current item. * * This has the same restrictions as RTTabProbe(), e.g. it's not permitted to * break the order of the table. * * @returns The replaced item. * @returns NULL if the current item is the NULL item. The traverser * and table remains unchanged. * @param pTrav The traverser. * @param pvItem The item to be inserted. */ DECLINLINE(void *) RTTabTravReplace(PRTTABTRAVERSERCORE pTrav, void *pvItem) { return pTrav->pTab->pOps->pfnTravReplace(pTrav, pvItem); } RT_C_DECLS_END /** @} */ #endif