src/gallium/auxiliary/util/u_hash_table.c

   1 /**************************************************************************
   2  *
   3  * Copyright 2008 VMware, Inc.
   4  * All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the
   8  * "Software"), to deal in the Software without restriction, including
   9  * without limitation the rights to use, copy, modify, merge, publish,
  10  * distribute, sub license, and/or sell copies of the Software, and to
  11  * permit persons to whom the Software is furnished to do so, subject to
  12  * the following conditions:
  13  *
  14  * The above copyright notice and this permission notice (including the
  15  * next paragraph) shall be included in all copies or substantial portions
  16  * of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  19  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
  21  * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
  22  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  23  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  24  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  **************************************************************************/
  27
  28
  29 #include "util/u_pointer.h"
  30 #include "util/u_hash_table.h"
  31
  32 #if DETECT_OS_UNIX
  33 #include <sys/stat.h>
  34 #endif
  35
  36
  37 static uint32_t
  38 pointer_hash(const void *key)
  39 {
  40    return _mesa_hash_pointer(key);
  41 }
  42
  43
  44 static bool
  45 pointer_equal(const void *a, const void *b)
  46 {
  47    return a == b;
  48 }
  49
  50
  51 struct hash_table *
  52 util_hash_table_create_ptr_keys(void)
  53 {
  54    return _mesa_hash_table_create(NULL, pointer_hash, pointer_equal);
  55 }
  56
  57
  58 static uint32_t hash_fd(const void *key)
  59 {
  60 #if DETECT_OS_UNIX
  61    int fd = pointer_to_intptr(key);
  62    struct stat stat;
  63
  64    fstat(fd, &stat);
  65
  66    return stat.st_dev ^ stat.st_ino ^ stat.st_rdev;
  67 #else
  68    return 0;
  69 #endif
  70 }
  71
  72
  73 static bool equal_fd(const void *key1, const void *key2)
  74 {
  75 #if DETECT_OS_UNIX
  76    int fd1 = pointer_to_intptr(key1);
  77    int fd2 = pointer_to_intptr(key2);
  78    struct stat stat1, stat2;
  79
  80    fstat(fd1, &stat1);
  81    fstat(fd2, &stat2);
  82
  83    return stat1.st_dev == stat2.st_dev &&
  84           stat1.st_ino == stat2.st_ino &&
  85           stat1.st_rdev == stat2.st_rdev;
  86 #else
  87    return 0;
  88 #endif
  89 }
  90
  91
  92 struct hash_table *
  93 util_hash_table_create_fd_keys(void)
  94 {
  95    return _mesa_hash_table_create(NULL, hash_fd, equal_fd);
  96 }
  97
  98
  99 void *
 100 util_hash_table_get(struct hash_table *ht,
 101                     void *key)
 102 {
 103    struct hash_entry *entry = _mesa_hash_table_search(ht, key);
 104
 105    return entry ? entry->data : NULL;
 106 }
 107
 108
 109 enum pipe_error
 110 util_hash_table_foreach(struct hash_table *ht,
 111                         enum pipe_error (*callback)
 112                         (void *key, void *value, void *data),
 113                         void *data)
 114 {
 115    hash_table_foreach(ht, entry) {
 116       enum pipe_error error = callback((void*)entry->key, entry->data, data);
 117       if (error != PIPE_OK)
 118          return error;
 119    }
 120    return PIPE_OK;
 121 }