1 2/*--------------------------------------------------------------------*/ 3/*--- OSet: a fast data structure with no dups. pub_tool_oset.h ---*/ 4/*--------------------------------------------------------------------*/ 5 6/* 7 This file is part of Valgrind, a dynamic binary instrumentation 8 framework. 9 10 Copyright (C) 2005-2012 Nicholas Nethercote 11 njn@valgrind.org 12 13 This program is free software; you can redistribute it and/or 14 modify it under the terms of the GNU General Public License as 15 published by the Free Software Foundation; either version 2 of the 16 License, or (at your option) any later version. 17 18 This program is distributed in the hope that it will be useful, but 19 WITHOUT ANY WARRANTY; without even the implied warranty of 20 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 21 General Public License for more details. 22 23 You should have received a copy of the GNU General Public License 24 along with this program; if not, write to the Free Software 25 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 26 02111-1307, USA. 27 28 The GNU General Public License is contained in the file COPYING. 29*/ 30 31#ifndef __PUB_TOOL_OSET_H 32#define __PUB_TOOL_OSET_H 33 34// This module implements an ordered set, a data structure with fast 35// (eg. amortised log(n) or better) insertion, lookup and deletion of 36// elements. It does not allow duplicates, and will assert if you insert a 37// duplicate to an OSet. 38// 39// It has two interfaces. 40// 41// - The "OSetWord_" interface provides an easier-to-use interface for the 42// case where you just want to store UWord-sized values. The user 43// provides the allocation and deallocation functions, and possibly a 44// comparison function. 45// 46// - The "OSetGen_" interface provides a totally generic interface, which 47// allows any kind of structure to be put into the set. The user provides 48// the allocation and deallocation functions. Also, each element has a 49// key, which the lookup is done with. The key may be the whole element 50// (eg. in an OSet of integers, each integer serves both as an element and 51// a key), or it may be only part of it (eg. if the key is a single field 52// in a struct). The user can provide a function that compares an element 53// with a key; this is very flexible, and with the right comparison 54// function even a (non-overlapping) interval list can be created. But 55// the cost of calling a function for every comparison can be high during 56// lookup. If no comparison function is provided, we assume that keys are 57// (signed or unsigned) words, and that the key is the first word in each 58// element. This fast comparison is suitable for an OSet containing 59// structs where the first element is an Addr, for example. 60// 61// Each OSet interface also has an iterator, which makes it simple to 62// traverse all the nodes in order. Note that the iterator maintains state 63// and so is non-reentrant. 64// 65// Note that once you insert an element into an OSet, if you modify any part 66// of it looked at by your cmp() function, this may cause incorrect 67// behaviour as the sorted order maintained will be wrong. 68 69/*--------------------------------------------------------------------*/ 70/*--- Types ---*/ 71/*--------------------------------------------------------------------*/ 72 73typedef struct _OSet OSet; 74 75// - Cmp: returns -1, 0 or 1 if key is <, == or > elem. 76// - Alloc: allocates a chunk of memory. 77// - Free: frees a chunk of memory allocated with Alloc. 78 79typedef Word (*OSetCmp_t) ( const void* key, const void* elem ); 80typedef void* (*OSetAlloc_t) ( HChar* cc, SizeT szB ); 81typedef void (*OSetFree_t) ( void* p ); 82 83/*--------------------------------------------------------------------*/ 84/*--- Creating and destroying OSets (UWord) ---*/ 85/*--------------------------------------------------------------------*/ 86 87// * Create: allocates and initialises the OSet. Arguments: 88// - alloc The allocation function used internally for allocating the 89// OSet and all its nodes. 90// - cc Cost centre string used by 'alloc'. 91// - free The deallocation function used internally for freeing nodes 92// called by VG_(OSetWord_Destroy)(). 93// 94// * CreateWithCmp: like Create, but you specify your own comparison 95// function. 96// 97// * Destroy: frees all nodes in the table, plus the memory used by 98// the table itself. The passed-in function is called on each node first 99// to allow the destruction of any attached resources; if NULL it is not 100// called. 101 102extern OSet* VG_(OSetWord_Create) ( OSetAlloc_t alloc, HChar* cc, 103 OSetFree_t _free ); 104extern void VG_(OSetWord_Destroy) ( OSet* os ); 105 106/*--------------------------------------------------------------------*/ 107/*--- Operations on OSets (UWord) ---*/ 108/*--------------------------------------------------------------------*/ 109 110// In everything that follows, the parameter 'key' is always the *address* 111// of the key, and 'elem' is *address* of the elem, as are the return values 112// of the functions that return elems. 113// 114// * Size: The number of elements in the set. 115// 116// * Contains: Determines if the value is in the set. 117// 118// * Insert: Inserts a new element into the set. Duplicates are forbidden, 119// and will cause assertion failures. 120// 121// * Remove: Removes the value from the set, if present. Returns a Bool 122// indicating if the value was removed. 123// 124// * ResetIter: Each OSet has an iterator. This resets it to point to the 125// first element in the OSet. 126// 127// * Next: Copies the next value according to the OSet's iterator into &val, 128// advances the iterator by one, and returns True; the elements are 129// visited in increasing order of unsigned words (UWord). Or, returns 130// False if the iterator has reached the set's end. 131// 132// You can thus iterate in order through a set like this: 133// 134// Word val; 135// VG_(OSetWord_ResetIter)(oset); 136// while ( VG_(OSetWord_Next)(oset, &val) ) { 137// ... do stuff with 'val' ... 138// } 139// 140// Note that iterators are cleared any time an element is inserted or 141// removed from the OSet, to avoid possible mayhem caused by the iterator 142// getting out of sync with the OSet's contents. "Cleared" means that 143// they will return False if VG_(OSetWord_Next)() is called without an 144// intervening call to VG_(OSetWord_ResetIter)(). 145 146extern Word VG_(OSetWord_Size) ( OSet* os ); 147extern void VG_(OSetWord_Insert) ( OSet* os, UWord val ); 148extern Bool VG_(OSetWord_Contains) ( OSet* os, UWord val ); 149extern Bool VG_(OSetWord_Remove) ( OSet* os, UWord val ); 150extern void VG_(OSetWord_ResetIter) ( OSet* os ); 151extern Bool VG_(OSetWord_Next) ( OSet* os, /*OUT*/UWord* val ); 152 153 154/*--------------------------------------------------------------------*/ 155/*--- Creating and destroying OSets and OSet members (Gen) ---*/ 156/*--------------------------------------------------------------------*/ 157 158// * Create: allocates and initialises the OSet. Arguments: 159// - keyOff The offset of the key within the element. 160// - cmp The comparison function between keys and elements, or NULL 161// if the OSet should use fast comparisons. 162// - alloc The allocation function used for allocating the OSet itself; 163// If a pool allocator is used, it's called to allocate pool of 164// nodes. 165// If no pool allocator is used, it's called for each 166// invocation of VG_(OSetGen_AllocNode)(). 167// - cc Cost centre string used by 'alloc'. 168// - free If no pool allocator is used, this is the deallocation 169// function used by VG_(OSetGen_FreeNode)() and 170// VG_(OSetGen_Destroy)(). 171// If a pool allocator is used, the memory used by the nodes is 172// deallocated when the pool is deleted. 173// (for more details about pool allocators, see pub_tool_poolalloc.h). 174// 175// 176// If cmp is NULL, keyOff must be zero. This is checked. 177// 178// * Destroy: frees all nodes in the table, plus the memory used by 179// the table itself. The passed-in function is called on each node first 180// to allow the destruction of any attached resources; if NULL it is not 181// called. 182// 183// * AllocNode: Allocate and zero memory for a node to go into the OSet. 184// If a pool allocator is used, it uses the pool allocator to allocate a node. 185// Otherwise, uses the alloc function given to VG_(OSetGen_Create)() to 186// allocate a node which is big enough for both an element and the OSet 187// metadata. 188// Not all elements in one OSet have to be the same size. 189// However, if a pool allocator is used, elements will all have a size equal 190// to the max user data size given at creation + the node meta data size. 191// 192// Note that the element allocated will be at most word-aligned, which may 193// be less aligned than the element type would normally be. 194// 195// * FreeNode: Deallocate a node allocated with OSetGen_AllocNode(). Using 196// a deallocation function (such as VG_(free)()) directly will likely 197// lead to assertions in Valgrind's allocator. 198 199extern OSet* VG_(OSetGen_Create) ( PtrdiffT keyOff, OSetCmp_t cmp, 200 OSetAlloc_t alloc, HChar* cc, 201 OSetFree_t _free); 202 203 204extern OSet* VG_(OSetGen_Create_With_Pool) ( PtrdiffT keyOff, OSetCmp_t cmp, 205 OSetAlloc_t alloc, HChar* cc, 206 OSetFree_t _free, 207 SizeT poolSize, 208 SizeT maxEltSize); 209// Same as VG_(OSetGen_Create) but created OSet will use a pool allocator to 210// allocate the nodes. 211// The node size is the sum of a fixed small meta data size needed for OSet 212// + the size of the user data element. 213// The maximum size for the user data element is specified by maxEltSize. 214// (if poolSize is 0, maxEltSize is not relevant for the OSet). 215// It is interesting to use a pool allocator when an OSet has many elements, 216// and these elements have a small fixed size, or have a variable size, but 217// always <= than a (small) maximum value. 218// In such a case, allocating the nodes in pools reduces significantly 219// the memory overhead needed by each node. 220// When a node is freed (i.e. OsetGen_Freenode is called), the node is 221// put back in the pool allocator free list (for sub-sequent re-use by 222// Osetgen_Allocnode). Note that the pool memory is only released when 223// the pool is destroyed : calls to VG_(OSetGen_Free) do not cause 224// any calls to OsetFree_t _free function. 225// If there are several OSet managing similar such elements, it might be 226// interesting to use a shared pool for these OSet. 227// To have multiple OSets sharing a pool allocator, create the first OSet 228// with VG_(OSetGen_Create). Create subsequent OSet with 229// VG_(OSetGen_EmptyClone). 230 231extern void VG_(OSetGen_Destroy) ( OSet* os ); 232extern void* VG_(OSetGen_AllocNode) ( OSet* os, SizeT elemSize ); 233extern void VG_(OSetGen_FreeNode) ( OSet* os, void* elem ); 234 235extern OSet* VG_(OSetGen_EmptyClone) (OSet* os); 236// Creates a new empty OSet. 237// The new OSet will have the same characteristics as os. 238// If os uses a pool allocator, this pool allocator will be shared with 239// the new OSet. A shared pool allocator is only deleted (and its memory is 240// released) when the last OSet using the shared pool is destroyed. 241 242/*-------------------------------------------------------------------*/ 243/*--- Operations on OSets (Gen) ---*/ 244/*--------------------------------------------------------------------*/ 245 246// In everything that follows, the parameter 'key' is always the *address* 247// of the key, and 'elem' is *address* of the elem, as are the return values 248// of the functions that return elems. 249// 250// * Size: The number of elements in the set. 251// 252// * Insert: Inserts a new element into the set. Note that 'elem' must 253// have been allocated using VG_(OSetGen_AllocNode)(), otherwise you will 254// get assertion failures about "bad magic". Duplicates are forbidden, 255// and will also cause assertion failures. 256// 257// * Contains: Determines if any element in the OSet matches the key. 258// 259// * Lookup: Returns a pointer to the element matching the key, if there is 260// one, otherwise returns NULL. 261// 262// * LookupWithCmp: Like Lookup, but you specify the comparison function, 263// which overrides the OSet's normal one. 264// 265// * Remove: Removes the element matching the key, if there is one. Returns 266// NULL if no element matches the key. 267// 268// * ResetIter: Each OSet has an iterator. This resets it to point to the 269// first element in the OSet. 270// 271// * ResetIterAt: Like ResetIter, but instead of resetting the iterator to the 272// smallest element, it resets the iterator to point to the smallest element 273// in the set whose key is greater-than-or-equal to the given key. (In many 274// cases this will be the element whose key equals that of the given key.) 275// 276// * Next: Returns a pointer to the element pointed to by the OSet's 277// iterator, and advances the iterator by one; the elements are visited 278// in order. Or, returns NULL if the iterator has reached the OSet's end. 279// 280// You can thus iterate in order through a set like this: 281// 282// VG_(OSetGen_ResetIter)(oset); 283// while ( (elem = VG_(OSetGen_Next)(oset)) ) { 284// ... do stuff with 'elem' ... 285// } 286// 287// Note that iterators are cleared any time an element is inserted or 288// removed from the OSet, to avoid possible mayhem caused by the iterator 289// getting out of sync with the OSet's contents. "Cleared" means that 290// they will return NULL if VG_(OSetGen_Next)() is called without an 291// intervening call to VG_(OSetGen_ResetIter)(). 292 293extern Word VG_(OSetGen_Size) ( const OSet* os ); 294extern void VG_(OSetGen_Insert) ( OSet* os, void* elem ); 295extern Bool VG_(OSetGen_Contains) ( const OSet* os, const void* key ); 296extern void* VG_(OSetGen_Lookup) ( const OSet* os, const void* key ); 297extern void* VG_(OSetGen_LookupWithCmp)( OSet* os, 298 const void* key, OSetCmp_t cmp ); 299extern void* VG_(OSetGen_Remove) ( OSet* os, const void* key ); 300extern void VG_(OSetGen_ResetIter) ( OSet* os ); 301extern void VG_(OSetGen_ResetIterAt) ( OSet* os, const void* key ); 302extern void* VG_(OSetGen_Next) ( OSet* os ); 303 304 305#endif // __PUB_TOOL_OSET_H 306 307/*--------------------------------------------------------------------*/ 308/*--- end ---*/ 309/*--------------------------------------------------------------------*/ 310