hashtable: Added src/SDL_hashtable.[ch].

Reference Issue #7799.
main
Ryan C. Gordon 2023-10-09 19:17:05 -04:00
parent 8745a9949b
commit 568902b64e
No known key found for this signature in database
GPG Key ID: FA148B892AB48044
9 changed files with 332 additions and 1 deletions

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@ -468,6 +468,7 @@
<PrecompiledHeaderOutputFile Condition="'$(Configuration)|$(Platform)'=='Release|Gaming.Desktop.x64'">$(IntDir)$(TargetName)_cpp.pch</PrecompiledHeaderOutputFile>
</ClCompile>
<ClCompile Include="..\..\src\SDL_guid.c" />
<ClInclude Include="..\..\src\SDL_hashtable.h" />
<ClInclude Include="..\..\src\SDL_hints_c.h" />
<ClInclude Include="..\..\src\SDL_internal.h" />
<ClInclude Include="..\..\src\SDL_list.h" />
@ -540,6 +541,7 @@
<ClInclude Include="..\..\src\video\yuv2rgb\yuv_rgb.h" />
<ClInclude Include="..\..\src\video\yuv2rgb\yuv_rgb_sse_func.h" />
<ClInclude Include="..\..\src\video\yuv2rgb\yuv_rgb_std_func.h" />
<ClCompile Include="..\..\src\SDL_hashtable.c" />
</ItemGroup>
<ItemGroup>
<ClCompile Include="..\..\src\atomic\SDL_atomic.c" />

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@ -397,6 +397,7 @@
<Filter>API Headers</Filter>
</ClInclude>
<ClInclude Include="..\..\src\SDL_error_c.h" />
<ClInclude Include="..\..\src\SDL_hashtable.h" />
<ClInclude Include="..\..\src\SDL_list.h" />
<ClInclude Include="..\..\include\SDL3\SDL_metal.h">
<Filter>API Headers</Filter>
@ -845,6 +846,7 @@
<ClCompile Include="..\..\src\SDL_assert.c" />
<ClCompile Include="..\..\src\SDL_error.c" />
<ClCompile Include="..\..\src\SDL_guid.c" />
<ClCompile Include="..\..\src\SDL_hashtable.c" />
<ClCompile Include="..\..\src\SDL_hints.c" />
<ClCompile Include="..\..\src\SDL_list.c" />
<ClCompile Include="..\..\src\SDL_utils.c" />

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@ -151,6 +151,7 @@
<ClInclude Include="..\src\SDL_assert_c.h" />
<ClInclude Include="..\src\SDL_error_c.h" />
<ClInclude Include="..\src\SDL_fatal.h" />
<ClInclude Include="..\src\SDL_hashtable.h" />
<ClInclude Include="..\src\SDL_hints_c.h" />
<ClInclude Include="..\src\SDL_internal.h" />
<ClInclude Include="..\src\SDL_list.h" />
@ -391,6 +392,7 @@
<ClCompile Include="..\src\render\software\SDL_triangle.c" />
<ClCompile Include="..\src\SDL.c" />
<ClCompile Include="..\src\SDL_assert.c" />
<ClCompile Include="..\src\SDL_hashtable.c" />
<ClCompile Include="..\src\SDL_list.c" />
<ClCompile Include="..\src\SDL_error.c" />
<ClCompile Include="..\src\SDL_guid.c" />

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@ -324,6 +324,7 @@
<ClInclude Include="..\src\SDL_fatal.h">
<Filter>Source Files</Filter>
</ClInclude>
<ClInclude Include="..\src\SDL_hashtable.h" />
<ClInclude Include="..\src\SDL_hints_c.h">
<Filter>Source Files</Filter>
</ClInclude>
@ -639,6 +640,7 @@
<ClCompile Include="..\src\SDL_guid.c">
<Filter>Source Files</Filter>
</ClCompile>
<ClCompile Include="..\src\SDL_hashtable.c" />
<ClCompile Include="..\src\SDL_hints.c">
<Filter>Source Files</Filter>
</ClCompile>

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@ -395,6 +395,7 @@
<PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Release|x64'">Create</PrecompiledHeader>
</ClCompile>
<ClCompile Include="..\..\src\SDL_guid.c" />
<ClInclude Include="..\..\src\SDL_hashtable.h" />
<ClInclude Include="..\..\src\SDL_hints_c.h" />
<ClInclude Include="..\..\src\SDL_internal.h" />
<ClInclude Include="..\..\src\SDL_list.h" />
@ -466,6 +467,7 @@
<ClInclude Include="..\..\src\video\yuv2rgb\yuv_rgb.h" />
<ClInclude Include="..\..\src\video\yuv2rgb\yuv_rgb_sse_func.h" />
<ClInclude Include="..\..\src\video\yuv2rgb\yuv_rgb_std_func.h" />
<ClCompile Include="..\..\src\SDL_hashtable.c" />
</ItemGroup>
<ItemGroup>
<ClCompile Include="..\..\src\atomic\SDL_atomic.c" />
@ -662,4 +664,4 @@
<Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
<ImportGroup Label="ExtensionTargets">
</ImportGroup>
</Project>
</Project>

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@ -388,6 +388,7 @@
<Filter>API Headers</Filter>
</ClInclude>
<ClInclude Include="..\..\src\SDL_error_c.h" />
<ClInclude Include="..\..\src\SDL_hashtable.h" />
<ClInclude Include="..\..\src\SDL_list.h" />
<ClInclude Include="..\..\include\SDL3\SDL_metal.h">
<Filter>API Headers</Filter>
@ -824,6 +825,7 @@
<ClCompile Include="..\..\src\SDL_assert.c" />
<ClCompile Include="..\..\src\SDL_error.c" />
<ClCompile Include="..\..\src\SDL_guid.c" />
<ClCompile Include="..\..\src\SDL_hashtable.c" />
<ClCompile Include="..\..\src\SDL_hints.c" />
<ClCompile Include="..\..\src\SDL_list.c" />
<ClCompile Include="..\..\src\SDL_utils.c" />

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@ -469,6 +469,8 @@
F3F7D9E12933074E00816151 /* SDL_begin_code.h in Headers */ = {isa = PBXBuildFile; fileRef = F3F7D8E72933074E00816151 /* SDL_begin_code.h */; settings = {ATTRIBUTES = (Public, ); }; };
F3F7D9E52933074E00816151 /* SDL_system.h in Headers */ = {isa = PBXBuildFile; fileRef = F3F7D8E82933074E00816151 /* SDL_system.h */; settings = {ATTRIBUTES = (Public, ); }; };
FA73671D19A540EF004122E4 /* CoreVideo.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = FA73671C19A540EF004122E4 /* CoreVideo.framework */; platformFilters = (ios, maccatalyst, macos, tvos, watchos, ); };
000040E76FDC6AE48CBF0000 /* SDL_hashtable.c in Sources */ = {isa = PBXBuildFile; fileRef = 000078E1881E857EBB6C0000 /* SDL_hashtable.c */; };
0000CE8F0EF0E7EF781D0000 /* SDL_hashtable.h in Headers */ = {isa = PBXBuildFile; fileRef = 0000B6ADCD88CAD6610F0000 /* SDL_hashtable.h */; };
/* End PBXBuildFile section */
/* Begin PBXContainerItemProxy section */
@ -962,6 +964,8 @@
F59C710600D5CB5801000001 /* SDL.info */ = {isa = PBXFileReference; fileEncoding = 30; lastKnownFileType = text; path = SDL.info; sourceTree = "<group>"; };
F5A2EF3900C6A39A01000001 /* BUGS.txt */ = {isa = PBXFileReference; fileEncoding = 30; lastKnownFileType = text; name = BUGS.txt; path = ../../BUGS.txt; sourceTree = SOURCE_ROOT; };
FA73671C19A540EF004122E4 /* CoreVideo.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = CoreVideo.framework; path = System/Library/Frameworks/CoreVideo.framework; sourceTree = SDKROOT; };
000078E1881E857EBB6C0000 /* SDL_hashtable.c */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.c; name = SDL_hashtable.c; path = SDL_hashtable.c; sourceTree = "<group>"; };
0000B6ADCD88CAD6610F0000 /* SDL_hashtable.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = SDL_hashtable.h; path = SDL_hashtable.h; sourceTree = "<group>"; };
/* End PBXFileReference section */
/* Begin PBXFrameworksBuildPhase section */
@ -1129,6 +1133,8 @@
F386F6E52884663E001840AA /* SDL_utils_c.h */,
F386F6E62884663E001840AA /* SDL_utils.c */,
A7D8A57123E2513D00DCD162 /* SDL.c */,
000078E1881E857EBB6C0000 /* SDL_hashtable.c */,
0000B6ADCD88CAD6610F0000 /* SDL_hashtable.h */,
);
name = "Library Source";
path = ../../src;
@ -2584,6 +2590,7 @@
A7D8AEA023E2514100DCD162 /* SDL_cocoavulkan.m in Sources */,
A7D8AB6123E2514100DCD162 /* SDL_offscreenwindow.c in Sources */,
566E26D8246274CC00718109 /* SDL_locale.c in Sources */,
000040E76FDC6AE48CBF0000 /* SDL_hashtable.c in Sources */,
);
runOnlyForDeploymentPostprocessing = 0;
};

259
src/SDL_hashtable.c Normal file
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@ -0,0 +1,259 @@
/*
Simple DirectMedia Layer
Copyright (C) 1997-2023 Sam Lantinga <slouken@libsdl.org>
This software is provided 'as-is', without any express 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.
*/
#include "SDL_internal.h"
#include "SDL_hashtable.h"
typedef struct SDL_HashItem
{
const void *key;
const void *value;
struct SDL_HashItem *next;
} SDL_HashItem;
struct SDL_HashTable
{
SDL_HashItem **table;
Uint32 table_len;
SDL_bool stackable;
void *data;
SDL_HashTable_HashFn hash;
SDL_HashTable_KeyMatchFn keymatch;
SDL_HashTable_NukeFn nuke;
};
SDL_HashTable *SDL_NewHashTable(void *data, const Uint32 num_buckets, const SDL_HashTable_HashFn hashfn,
const SDL_HashTable_KeyMatchFn keymatchfn,
const SDL_HashTable_NukeFn nukefn,
const SDL_bool stackable)
{
SDL_HashTable *table;
/* num_buckets must be a power of two so we get a solid block of bits to mask hash values against. */
if ((num_buckets == 0) || ((num_buckets & (num_buckets - 1)) != 0)) {
SDL_SetError("num_buckets must be a power of two");
return NULL;
}
table = (SDL_HashTable *) SDL_calloc(1, sizeof (SDL_HashTable));
if (table == NULL) {
SDL_OutOfMemory();
return NULL;
}
table->table = (SDL_HashItem **) SDL_calloc(num_buckets, sizeof (SDL_HashItem *));
if (table->table == NULL) {
SDL_free(table);
SDL_OutOfMemory();
return NULL;
}
table->table_len = num_buckets;
table->stackable = stackable;
table->data = data;
table->hash = hashfn;
table->keymatch = keymatchfn;
table->nuke = nukefn;
return table;
}
static SDL_INLINE Uint32 calc_hash(const SDL_HashTable *table, const void *key)
{
return table->hash(key, table->data) & (table->table_len - 1);
}
SDL_bool SDL_InsertIntoHashTable(SDL_HashTable *table, const void *key, const void *value)
{
SDL_HashItem *item;
const Uint32 hash = calc_hash(table, key);
if ( (!table->stackable) && (SDL_FindInHashTable(table, key, NULL)) ) {
return SDL_FALSE;
}
/* !!! FIXME: grow and rehash table if it gets too saturated. */
item = (SDL_HashItem *) SDL_malloc(sizeof (SDL_HashItem));
if (item == NULL) {
SDL_OutOfMemory();
return SDL_FALSE;
}
item->key = key;
item->value = value;
item->next = table->table[hash];
table->table[hash] = item;
return SDL_TRUE;
}
SDL_bool SDL_FindInHashTable(const SDL_HashTable *table, const void *key, const void **_value)
{
const Uint32 hash = calc_hash(table, key);
void *data = table->data;
SDL_HashItem *prev = NULL;
SDL_HashItem *i;
for (i = table->table[hash]; i != NULL; i = i->next) {
if (table->keymatch(key, i->key, data)) {
if (_value != NULL) {
*_value = i->value;
}
/* Matched! Move to the front of list for faster lookup next time.
(stackable tables have to remain in the same order, though!) */
if ((!table->stackable) && (prev != NULL)) {
SDL_assert(prev->next == i);
prev->next = i->next;
i->next = table->table[hash];
table->table[hash] = i;
}
return SDL_TRUE;
}
prev = i;
}
return SDL_FALSE;
}
SDL_bool SDL_RemoveFromHashTable(SDL_HashTable *table, const void *key)
{
const Uint32 hash = calc_hash(table, key);
SDL_HashItem *item = NULL;
SDL_HashItem *prev = NULL;
void *data = table->data;
for (item = table->table[hash]; item != NULL; item = item->next) {
if (table->keymatch(key, item->key, data)) {
if (prev != NULL) {
prev->next = item->next;
} else {
table->table[hash] = item->next;
}
table->nuke(item->key, item->value, data);
SDL_free(item);
return SDL_TRUE;
}
prev = item;
}
return SDL_FALSE;
}
SDL_bool SDL_IterateHashTable(const SDL_HashTable *table, const void *key, const void **_value, void **iter)
{
SDL_HashItem *item = iter ? ((SDL_HashItem *) *iter)->next : table->table[calc_hash(table, key)];
while (item != NULL) {
if (table->keymatch(key, item->key, table->data)) {
*_value = item->value;
*iter = item;
return SDL_TRUE;
}
item = item->next;
}
/* no more matches. */
*_value = NULL;
*iter = NULL;
return SDL_FALSE;
}
SDL_bool SDL_IterateHashTableKeys(const SDL_HashTable *table, const void **_key, void **iter)
{
SDL_HashItem *item = (SDL_HashItem *) *iter;
Uint32 idx = 0;
if (item != NULL) {
const SDL_HashItem *orig = item;
item = item->next;
if (item == NULL) {
idx = calc_hash(table, orig->key) + 1;
}
}
while (!item && (idx < table->table_len)) {
item = table->table[idx++]; /* skip empty buckets... */
}
if (item == NULL) { /* no more matches? */
*_key = NULL;
*iter = NULL;
return SDL_FALSE;
}
*_key = item->key;
*iter = item;
return SDL_TRUE;
}
void SDL_FreeHashTable(SDL_HashTable *table)
{
if (table != NULL) {
void *data = table->data;
Uint32 i;
for (i = 0; i < table->table_len; i++) {
SDL_HashItem *item = table->table[i];
while (item != NULL) {
SDL_HashItem *next = item->next;
table->nuke(item->key, item->value, data);
SDL_free(item);
item = next;
}
}
SDL_free(table->table);
SDL_free(table);
}
}
/* this is djb's xor hashing function. */
static SDL_INLINE Uint32 hash_string_djbxor(const char *str, size_t len)
{
Uint32 hash = 5381;
while (len--) {
hash = ((hash << 5) + hash) ^ *(str++);
}
return hash;
}
Uint32 SDL_HashString(const void *sym, void *data)
{
const char *str = (const char*) sym;
return hash_string_djbxor(str, SDL_strlen((const char *) str));
}
SDL_bool SDL_KeyMatchString(const void *a, const void *b, void *data)
{
if (a == b) {
return SDL_TRUE; /* same pointer, must match. */
} else if (!a || !b) {
return SDL_FALSE; /* one pointer is NULL (and first test shows they aren't the same pointer), must not match. */
}
return (SDL_strcmp((const char *) a, (const char *) b) == 0) ? SDL_TRUE : SDL_FALSE; /* Check against actual string contents. */
}
/* vi: set ts=4 sw=4 expandtab: */

53
src/SDL_hashtable.h Normal file
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@ -0,0 +1,53 @@
/*
Simple DirectMedia Layer
Copyright (C) 1997-2022 Sam Lantinga <slouken@libsdl.org>
This software is provided 'as-is', without any express 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.
*/
#ifndef SDL_hashtable_h_
#define SDL_hashtable_h_
/* this is not (currently) a public API. But maybe it should be! */
struct SDL_HashTable;
typedef struct SDL_HashTable SDL_HashTable;
typedef Uint32 (*SDL_HashTable_HashFn)(const void *key, void *data);
typedef SDL_bool (*SDL_HashTable_KeyMatchFn)(const void *a, const void *b, void *data);
typedef void (*SDL_HashTable_NukeFn)(const void *key, const void *value, void *data);
SDL_HashTable *SDL_NewHashTable(void *data,
const Uint32 num_buckets,
const SDL_HashTable_HashFn hashfn,
const SDL_HashTable_KeyMatchFn keymatchfn,
const SDL_HashTable_NukeFn nukefn,
const SDL_bool stackable);
void SDL_FreeHashTable(SDL_HashTable *table);
SDL_bool SDL_InsertIntoHashTable(SDL_HashTable *table, const void *key, const void *value);
SDL_bool SDL_RemoveFromHashTable(SDL_HashTable *table, const void *key);
SDL_bool SDL_FindInHashTable(const SDL_HashTable *table, const void *key, const void **_value);
SDL_bool SDL_IterateHashTable(const SDL_HashTable *table, const void *key, const void **_value, void **iter);
SDL_bool SDL_IterateHashTableKeys(const SDL_HashTable *table, const void **_key, void **iter);
Uint32 SDL_HashString(const void *sym, void *unused);
SDL_bool SDL_KeyMatchString(const void *a, const void *b, void *unused);
#endif /* SDL_hashtable_h_ */
/* vi: set ts=4 sw=4 expandtab: */