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115033338b
Factor out the code for setting up the hash table size, mask and mod, detecting valgrind and allocating the arrays for hashes, keys, and values. Make use of this new function from g_hash_table_remove_all_nodes(). The handling of have_big_keys and have_big_values was never correct in this function because it reallocated the array without changing the flags in the struct. Any calls in to the hashtable from destroy notifies would find the table in an inconsistent state. Many thanks to Thomas Haller who is essentially responsible for all the real work in this patch: both discovering and identifying the original problem, as well as finding the solution to it.
2498 lines
76 KiB
C
2498 lines
76 KiB
C
/* GLIB - Library of useful routines for C programming
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* Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
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*
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* This library is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with this library; if not, see <http://www.gnu.org/licenses/>.
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*/
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/*
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* Modified by the GLib Team and others 1997-2000. See the AUTHORS
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* file for a list of people on the GLib Team. See the ChangeLog
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* files for a list of changes. These files are distributed with
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* GLib at ftp://ftp.gtk.org/pub/gtk/.
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*/
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/*
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* MT safe
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*/
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#include "config.h"
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#include <string.h> /* memset */
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#include "ghash.h"
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#include "gmacros.h"
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#include "glib-private.h"
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#include "gstrfuncs.h"
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#include "gatomic.h"
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#include "gtestutils.h"
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#include "gslice.h"
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#include "grefcount.h"
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#include "gvalgrind.h"
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/* The following #pragma is here so we can do this...
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*
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* #ifndef USE_SMALL_ARRAYS
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* is_big = TRUE;
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* #endif
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* return is_big ? *(((gpointer *) a) + index) : GUINT_TO_POINTER (*(((guint *) a) + index));
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*
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* ...instead of this...
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*
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* #ifndef USE_SMALL_ARRAYS
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* return *(((gpointer *) a) + index);
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* #else
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* return is_big ? *(((gpointer *) a) + index) : GUINT_TO_POINTER (*(((guint *) a) + index));
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* #endif
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*
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* ...and still compile successfully when -Werror=duplicated-branches is passed. */
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#if defined(__GNUC__) && __GNUC__ > 6
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#pragma GCC diagnostic ignored "-Wduplicated-branches"
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#endif
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/**
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* SECTION:hash_tables
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* @title: Hash Tables
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* @short_description: associations between keys and values so that
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* given a key the value can be found quickly
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*
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* A #GHashTable provides associations between keys and values which is
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* optimized so that given a key, the associated value can be found
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* very quickly.
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*
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* Note that neither keys nor values are copied when inserted into the
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* #GHashTable, so they must exist for the lifetime of the #GHashTable.
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* This means that the use of static strings is OK, but temporary
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* strings (i.e. those created in buffers and those returned by GTK+
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* widgets) should be copied with g_strdup() before being inserted.
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*
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* If keys or values are dynamically allocated, you must be careful to
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* ensure that they are freed when they are removed from the
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* #GHashTable, and also when they are overwritten by new insertions
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* into the #GHashTable. It is also not advisable to mix static strings
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* and dynamically-allocated strings in a #GHashTable, because it then
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* becomes difficult to determine whether the string should be freed.
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*
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* To create a #GHashTable, use g_hash_table_new().
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*
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* To insert a key and value into a #GHashTable, use
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* g_hash_table_insert().
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*
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* To look up a value corresponding to a given key, use
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* g_hash_table_lookup() and g_hash_table_lookup_extended().
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*
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* g_hash_table_lookup_extended() can also be used to simply
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* check if a key is present in the hash table.
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*
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* To remove a key and value, use g_hash_table_remove().
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*
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* To call a function for each key and value pair use
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* g_hash_table_foreach() or use a iterator to iterate over the
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* key/value pairs in the hash table, see #GHashTableIter.
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*
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* To destroy a #GHashTable use g_hash_table_destroy().
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*
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* A common use-case for hash tables is to store information about a
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* set of keys, without associating any particular value with each
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* key. GHashTable optimizes one way of doing so: If you store only
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* key-value pairs where key == value, then GHashTable does not
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* allocate memory to store the values, which can be a considerable
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* space saving, if your set is large. The functions
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* g_hash_table_add() and g_hash_table_contains() are designed to be
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* used when using #GHashTable this way.
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*
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* #GHashTable is not designed to be statically initialised with keys and
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* values known at compile time. To build a static hash table, use a tool such
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* as [gperf](https://www.gnu.org/software/gperf/).
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*/
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/**
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* GHashTable:
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*
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* The #GHashTable struct is an opaque data structure to represent a
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* [Hash Table][glib-Hash-Tables]. It should only be accessed via the
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* following functions.
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*/
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/**
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* GHashFunc:
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* @key: a key
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*
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* Specifies the type of the hash function which is passed to
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* g_hash_table_new() when a #GHashTable is created.
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*
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* The function is passed a key and should return a #guint hash value.
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* The functions g_direct_hash(), g_int_hash() and g_str_hash() provide
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* hash functions which can be used when the key is a #gpointer, #gint*,
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* and #gchar* respectively.
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*
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* g_direct_hash() is also the appropriate hash function for keys
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* of the form `GINT_TO_POINTER (n)` (or similar macros).
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*
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* A good hash functions should produce
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* hash values that are evenly distributed over a fairly large range.
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* The modulus is taken with the hash table size (a prime number) to
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* find the 'bucket' to place each key into. The function should also
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* be very fast, since it is called for each key lookup.
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*
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* Note that the hash functions provided by GLib have these qualities,
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* but are not particularly robust against manufactured keys that
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* cause hash collisions. Therefore, you should consider choosing
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* a more secure hash function when using a GHashTable with keys
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* that originate in untrusted data (such as HTTP requests).
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* Using g_str_hash() in that situation might make your application
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* vulerable to
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* [Algorithmic Complexity Attacks](https://lwn.net/Articles/474912/).
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*
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* The key to choosing a good hash is unpredictability. Even
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* cryptographic hashes are very easy to find collisions for when the
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* remainder is taken modulo a somewhat predictable prime number. There
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* must be an element of randomness that an attacker is unable to guess.
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*
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* Returns: the hash value corresponding to the key
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*/
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/**
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* GHFunc:
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* @key: a key
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* @value: the value corresponding to the key
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* @user_data: user data passed to g_hash_table_foreach()
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*
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* Specifies the type of the function passed to g_hash_table_foreach().
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* It is called with each key/value pair, together with the @user_data
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* parameter which is passed to g_hash_table_foreach().
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*/
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/**
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* GHRFunc:
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* @key: a key
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* @value: the value associated with the key
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* @user_data: user data passed to g_hash_table_remove()
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*
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* Specifies the type of the function passed to
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* g_hash_table_foreach_remove(). It is called with each key/value
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* pair, together with the @user_data parameter passed to
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* g_hash_table_foreach_remove(). It should return %TRUE if the
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* key/value pair should be removed from the #GHashTable.
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*
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* Returns: %TRUE if the key/value pair should be removed from the
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* #GHashTable
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*/
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/**
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* GEqualFunc:
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* @a: a value
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* @b: a value to compare with
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*
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* Specifies the type of a function used to test two values for
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* equality. The function should return %TRUE if both values are equal
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* and %FALSE otherwise.
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*
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* Returns: %TRUE if @a = @b; %FALSE otherwise
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*/
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/**
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* GHashTableIter:
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*
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* A GHashTableIter structure represents an iterator that can be used
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* to iterate over the elements of a #GHashTable. GHashTableIter
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* structures are typically allocated on the stack and then initialized
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* with g_hash_table_iter_init().
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*/
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/**
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* g_hash_table_freeze:
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* @hash_table: a #GHashTable
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*
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* This function is deprecated and will be removed in the next major
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* release of GLib. It does nothing.
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*/
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/**
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* g_hash_table_thaw:
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* @hash_table: a #GHashTable
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*
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* This function is deprecated and will be removed in the next major
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* release of GLib. It does nothing.
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*/
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#define HASH_TABLE_MIN_SHIFT 3 /* 1 << 3 == 8 buckets */
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#define UNUSED_HASH_VALUE 0
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#define TOMBSTONE_HASH_VALUE 1
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#define HASH_IS_UNUSED(h_) ((h_) == UNUSED_HASH_VALUE)
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#define HASH_IS_TOMBSTONE(h_) ((h_) == TOMBSTONE_HASH_VALUE)
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#define HASH_IS_REAL(h_) ((h_) >= 2)
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/* If int is smaller than void * on our arch, we start out with
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* int-sized keys and values and resize to pointer-sized entries as
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* needed. This saves a good amount of memory when the HT is being
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* used with e.g. GUINT_TO_POINTER(). */
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#define BIG_ENTRY_SIZE (SIZEOF_VOID_P)
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#define SMALL_ENTRY_SIZE (SIZEOF_INT)
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#if SMALL_ENTRY_SIZE < BIG_ENTRY_SIZE
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# define USE_SMALL_ARRAYS
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#endif
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struct _GHashTable
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{
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gsize size;
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gint mod;
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guint mask;
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gint nnodes;
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gint noccupied; /* nnodes + tombstones */
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guint have_big_keys : 1;
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guint have_big_values : 1;
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gpointer keys;
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guint *hashes;
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gpointer values;
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GHashFunc hash_func;
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GEqualFunc key_equal_func;
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gatomicrefcount ref_count;
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#ifndef G_DISABLE_ASSERT
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/*
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* Tracks the structure of the hash table, not its contents: is only
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* incremented when a node is added or removed (is not incremented
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* when the key or data of a node is modified).
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*/
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int version;
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#endif
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GDestroyNotify key_destroy_func;
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GDestroyNotify value_destroy_func;
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};
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typedef struct
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{
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GHashTable *hash_table;
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gpointer dummy1;
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gpointer dummy2;
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gint position;
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gboolean dummy3;
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gint version;
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} RealIter;
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G_STATIC_ASSERT (sizeof (GHashTableIter) == sizeof (RealIter));
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G_STATIC_ASSERT (G_ALIGNOF (GHashTableIter) >= G_ALIGNOF (RealIter));
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/* Each table size has an associated prime modulo (the first prime
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* lower than the table size) used to find the initial bucket. Probing
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* then works modulo 2^n. The prime modulo is necessary to get a
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* good distribution with poor hash functions.
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*/
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static const gint prime_mod [] =
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{
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1, /* For 1 << 0 */
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2,
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3,
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7,
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13,
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31,
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61,
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127,
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251,
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509,
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1021,
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2039,
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4093,
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8191,
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16381,
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32749,
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65521, /* For 1 << 16 */
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131071,
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262139,
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524287,
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1048573,
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2097143,
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4194301,
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8388593,
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16777213,
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33554393,
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67108859,
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134217689,
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268435399,
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536870909,
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1073741789,
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2147483647 /* For 1 << 31 */
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};
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static void
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g_hash_table_set_shift (GHashTable *hash_table, gint shift)
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{
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hash_table->size = 1 << shift;
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hash_table->mod = prime_mod [shift];
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/* hash_table->size is always a power of two, so we can calculate the mask
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* by simply subtracting 1 from it. The leading assertion ensures that
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* we're really dealing with a power of two. */
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g_assert ((hash_table->size & (hash_table->size - 1)) == 0);
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hash_table->mask = hash_table->size - 1;
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}
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static gint
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g_hash_table_find_closest_shift (gint n)
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{
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gint i;
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for (i = 0; n; i++)
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n >>= 1;
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return i;
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}
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static void
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g_hash_table_set_shift_from_size (GHashTable *hash_table, gint size)
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{
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gint shift;
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shift = g_hash_table_find_closest_shift (size);
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shift = MAX (shift, HASH_TABLE_MIN_SHIFT);
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g_hash_table_set_shift (hash_table, shift);
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}
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static inline gpointer
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g_hash_table_realloc_key_or_value_array (gpointer a, guint size, G_GNUC_UNUSED gboolean is_big)
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{
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#ifdef USE_SMALL_ARRAYS
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return g_realloc (a, size * (is_big ? BIG_ENTRY_SIZE : SMALL_ENTRY_SIZE));
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#else
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return g_renew (gpointer, a, size);
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#endif
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}
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static inline gpointer
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g_hash_table_fetch_key_or_value (gpointer a, guint index, gboolean is_big)
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{
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#ifndef USE_SMALL_ARRAYS
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is_big = TRUE;
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#endif
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return is_big ? *(((gpointer *) a) + index) : GUINT_TO_POINTER (*(((guint *) a) + index));
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}
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static inline void
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g_hash_table_assign_key_or_value (gpointer a, guint index, gboolean is_big, gpointer v)
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{
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#ifndef USE_SMALL_ARRAYS
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is_big = TRUE;
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#endif
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if (is_big)
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*(((gpointer *) a) + index) = v;
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else
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*(((guint *) a) + index) = GPOINTER_TO_UINT (v);
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}
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static inline gpointer
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g_hash_table_evict_key_or_value (gpointer a, guint index, gboolean is_big, gpointer v)
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{
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#ifndef USE_SMALL_ARRAYS
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is_big = TRUE;
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#endif
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if (is_big)
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{
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gpointer r = *(((gpointer *) a) + index);
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*(((gpointer *) a) + index) = v;
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return r;
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}
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else
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{
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gpointer r = GUINT_TO_POINTER (*(((guint *) a) + index));
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*(((guint *) a) + index) = GPOINTER_TO_UINT (v);
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return r;
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}
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}
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static inline guint
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g_hash_table_hash_to_index (GHashTable *hash_table, guint hash)
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{
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/* Multiply the hash by a small prime before applying the modulo. This
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* prevents the table from becoming densely packed, even with a poor hash
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* function. A densely packed table would have poor performance on
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* workloads with many failed lookups or a high degree of churn. */
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return (hash * 11) % hash_table->mod;
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}
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/*
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* g_hash_table_lookup_node:
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* @hash_table: our #GHashTable
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* @key: the key to look up against
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* @hash_return: key hash return location
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*
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* Performs a lookup in the hash table, preserving extra information
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* usually needed for insertion.
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*
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* This function first computes the hash value of the key using the
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* user's hash function.
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*
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* If an entry in the table matching @key is found then this function
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* returns the index of that entry in the table, and if not, the
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* index of an unused node (empty or tombstone) where the key can be
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* inserted.
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*
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* The computed hash value is returned in the variable pointed to
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* by @hash_return. This is to save insertions from having to compute
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* the hash record again for the new record.
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*
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* Returns: index of the described node
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*/
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static inline guint
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g_hash_table_lookup_node (GHashTable *hash_table,
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gconstpointer key,
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guint *hash_return)
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{
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guint node_index;
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guint node_hash;
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guint hash_value;
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guint first_tombstone = 0;
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gboolean have_tombstone = FALSE;
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guint step = 0;
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/* If this happens, then the application is probably doing too much work
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* from a destroy notifier. The alternative would be to crash any second
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* (as keys, etc. will be NULL).
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* Applications need to either use g_hash_table_destroy, or ensure the hash
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* table is empty prior to removing the last reference using g_hash_table_unref(). */
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g_assert (!g_atomic_ref_count_compare (&hash_table->ref_count, 0));
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hash_value = hash_table->hash_func (key);
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if (G_UNLIKELY (!HASH_IS_REAL (hash_value)))
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hash_value = 2;
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*hash_return = hash_value;
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node_index = g_hash_table_hash_to_index (hash_table, hash_value);
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node_hash = hash_table->hashes[node_index];
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while (!HASH_IS_UNUSED (node_hash))
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{
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/* We first check if our full hash values
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* are equal so we can avoid calling the full-blown
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* key equality function in most cases.
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*/
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if (node_hash == hash_value)
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{
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gpointer node_key = g_hash_table_fetch_key_or_value (hash_table->keys, node_index, hash_table->have_big_keys);
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if (hash_table->key_equal_func)
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{
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if (hash_table->key_equal_func (node_key, key))
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return node_index;
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}
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else if (node_key == key)
|
|
{
|
|
return node_index;
|
|
}
|
|
}
|
|
else if (HASH_IS_TOMBSTONE (node_hash) && !have_tombstone)
|
|
{
|
|
first_tombstone = node_index;
|
|
have_tombstone = TRUE;
|
|
}
|
|
|
|
step++;
|
|
node_index += step;
|
|
node_index &= hash_table->mask;
|
|
node_hash = hash_table->hashes[node_index];
|
|
}
|
|
|
|
if (have_tombstone)
|
|
return first_tombstone;
|
|
|
|
return node_index;
|
|
}
|
|
|
|
/*
|
|
* g_hash_table_remove_node:
|
|
* @hash_table: our #GHashTable
|
|
* @node: pointer to node to remove
|
|
* @notify: %TRUE if the destroy notify handlers are to be called
|
|
*
|
|
* Removes a node from the hash table and updates the node count.
|
|
* The node is replaced by a tombstone. No table resize is performed.
|
|
*
|
|
* If @notify is %TRUE then the destroy notify functions are called
|
|
* for the key and value of the hash node.
|
|
*/
|
|
static void
|
|
g_hash_table_remove_node (GHashTable *hash_table,
|
|
gint i,
|
|
gboolean notify)
|
|
{
|
|
gpointer key;
|
|
gpointer value;
|
|
|
|
key = g_hash_table_fetch_key_or_value (hash_table->keys, i, hash_table->have_big_keys);
|
|
value = g_hash_table_fetch_key_or_value (hash_table->values, i, hash_table->have_big_values);
|
|
|
|
/* Erect tombstone */
|
|
hash_table->hashes[i] = TOMBSTONE_HASH_VALUE;
|
|
|
|
/* Be GC friendly */
|
|
g_hash_table_assign_key_or_value (hash_table->keys, i, hash_table->have_big_keys, NULL);
|
|
g_hash_table_assign_key_or_value (hash_table->values, i, hash_table->have_big_values, NULL);
|
|
|
|
hash_table->nnodes--;
|
|
|
|
if (notify && hash_table->key_destroy_func)
|
|
hash_table->key_destroy_func (key);
|
|
|
|
if (notify && hash_table->value_destroy_func)
|
|
hash_table->value_destroy_func (value);
|
|
|
|
}
|
|
|
|
/*
|
|
* g_hash_table_setup_storage:
|
|
* @hash_table: our #GHashTable
|
|
*
|
|
* Initialise the hash table size, mask, mod, and arrays.
|
|
*/
|
|
static void
|
|
g_hash_table_setup_storage (GHashTable *hash_table)
|
|
{
|
|
gboolean small;
|
|
|
|
/* We want to use small arrays only if:
|
|
* - we are running on a system where that makes sense (64 bit); and
|
|
* - we are not running under valgrind.
|
|
*/
|
|
small = FALSE;
|
|
|
|
#ifdef USE_SMALL_ARRAYS
|
|
small = TRUE;
|
|
|
|
# ifdef ENABLE_VALGRIND
|
|
if (RUNNING_ON_VALGRIND)
|
|
small = FALSE;
|
|
# endif
|
|
#endif
|
|
|
|
g_hash_table_set_shift (hash_table, HASH_TABLE_MIN_SHIFT);
|
|
|
|
hash_table->have_big_keys = !small;
|
|
hash_table->have_big_values = !small;
|
|
|
|
hash_table->keys = g_hash_table_realloc_key_or_value_array (NULL, hash_table->size, hash_table->have_big_keys);
|
|
hash_table->values = hash_table->keys;
|
|
hash_table->hashes = g_new0 (guint, hash_table->size);
|
|
}
|
|
|
|
/*
|
|
* g_hash_table_remove_all_nodes:
|
|
* @hash_table: our #GHashTable
|
|
* @notify: %TRUE if the destroy notify handlers are to be called
|
|
*
|
|
* Removes all nodes from the table.
|
|
*
|
|
* If @notify is %TRUE then the destroy notify functions are called
|
|
* for the key and value of the hash node.
|
|
*
|
|
* Since this may be a precursor to freeing the table entirely, we'd
|
|
* ideally perform no resize, and we can indeed avoid that in some
|
|
* cases. However: in the case that we'll be making callbacks to user
|
|
* code (via destroy notifies) we need to consider that the user code
|
|
* might call back into the table again. In this case, we setup a new
|
|
* set of arrays so that any callers will see an empty (but valid)
|
|
* table.
|
|
*/
|
|
static void
|
|
g_hash_table_remove_all_nodes (GHashTable *hash_table,
|
|
gboolean notify,
|
|
gboolean destruction)
|
|
{
|
|
int i;
|
|
gpointer key;
|
|
gpointer value;
|
|
gint old_size;
|
|
gpointer *old_keys;
|
|
gpointer *old_values;
|
|
guint *old_hashes;
|
|
gboolean old_have_big_keys;
|
|
gboolean old_have_big_values;
|
|
|
|
/* If the hash table is already empty, there is nothing to be done. */
|
|
if (hash_table->nnodes == 0)
|
|
return;
|
|
|
|
hash_table->nnodes = 0;
|
|
hash_table->noccupied = 0;
|
|
|
|
/* Easy case: no callbacks, so we just zero out the arrays */
|
|
if (!notify ||
|
|
(hash_table->key_destroy_func == NULL &&
|
|
hash_table->value_destroy_func == NULL))
|
|
{
|
|
if (!destruction)
|
|
{
|
|
memset (hash_table->hashes, 0, hash_table->size * sizeof (guint));
|
|
|
|
#ifdef USE_SMALL_ARRAYS
|
|
memset (hash_table->keys, 0, hash_table->size * (hash_table->have_big_keys ? BIG_ENTRY_SIZE : SMALL_ENTRY_SIZE));
|
|
memset (hash_table->values, 0, hash_table->size * (hash_table->have_big_values ? BIG_ENTRY_SIZE : SMALL_ENTRY_SIZE));
|
|
#else
|
|
memset (hash_table->keys, 0, hash_table->size * sizeof (gpointer));
|
|
memset (hash_table->values, 0, hash_table->size * sizeof (gpointer));
|
|
#endif
|
|
}
|
|
|
|
return;
|
|
}
|
|
|
|
/* Hard case: we need to do user callbacks. There are two
|
|
* possibilities here:
|
|
*
|
|
* 1) there are no outstanding references on the table and therefore
|
|
* nobody should be calling into it again (destroying == true)
|
|
*
|
|
* 2) there are outstanding references, and there may be future
|
|
* calls into the table, either after we return, or from the destroy
|
|
* notifies that we're about to do (destroying == false)
|
|
*
|
|
* We handle both cases by taking the current state of the table into
|
|
* local variables and replacing it with something else: in the "no
|
|
* outstanding references" cases we replace it with a bunch of
|
|
* null/zero values so that any access to the table will fail. In the
|
|
* "may receive future calls" case, we reinitialise the struct to
|
|
* appear like a newly-created empty table.
|
|
*
|
|
* In both cases, we take over the references for the current state,
|
|
* freeing them below.
|
|
*/
|
|
old_size = hash_table->size;
|
|
old_have_big_keys = hash_table->have_big_keys;
|
|
old_have_big_values = hash_table->have_big_values;
|
|
old_keys = g_steal_pointer (&hash_table->keys);
|
|
old_values = g_steal_pointer (&hash_table->values);
|
|
old_hashes = g_steal_pointer (&hash_table->hashes);
|
|
|
|
if (!destruction)
|
|
/* Any accesses will see an empty table */
|
|
g_hash_table_setup_storage (hash_table);
|
|
else
|
|
/* Will cause a quick crash on any attempted access */
|
|
hash_table->size = hash_table->mod = hash_table->mask = 0;
|
|
|
|
/* Now do the actual destroy notifies */
|
|
for (i = 0; i < old_size; i++)
|
|
{
|
|
if (HASH_IS_REAL (old_hashes[i]))
|
|
{
|
|
key = g_hash_table_fetch_key_or_value (old_keys, i, old_have_big_keys);
|
|
value = g_hash_table_fetch_key_or_value (old_values, i, old_have_big_values);
|
|
|
|
old_hashes[i] = UNUSED_HASH_VALUE;
|
|
|
|
g_hash_table_assign_key_or_value (old_keys, i, old_have_big_keys, NULL);
|
|
g_hash_table_assign_key_or_value (old_values, i, old_have_big_values, NULL);
|
|
|
|
if (hash_table->key_destroy_func != NULL)
|
|
hash_table->key_destroy_func (key);
|
|
|
|
if (hash_table->value_destroy_func != NULL)
|
|
hash_table->value_destroy_func (value);
|
|
}
|
|
}
|
|
|
|
/* Destroy old storage space. */
|
|
if (old_keys != old_values)
|
|
g_free (old_values);
|
|
|
|
g_free (old_keys);
|
|
g_free (old_hashes);
|
|
}
|
|
|
|
static void
|
|
realloc_arrays (GHashTable *hash_table, gboolean is_a_set)
|
|
{
|
|
hash_table->hashes = g_renew (guint, hash_table->hashes, hash_table->size);
|
|
hash_table->keys = g_hash_table_realloc_key_or_value_array (hash_table->keys, hash_table->size, hash_table->have_big_keys);
|
|
|
|
if (is_a_set)
|
|
hash_table->values = hash_table->keys;
|
|
else
|
|
hash_table->values = g_hash_table_realloc_key_or_value_array (hash_table->values, hash_table->size, hash_table->have_big_values);
|
|
}
|
|
|
|
/* When resizing the table in place, we use a temporary bit array to keep
|
|
* track of which entries have been assigned a proper location in the new
|
|
* table layout.
|
|
*
|
|
* Each bit corresponds to a bucket. A bit is set if an entry was assigned
|
|
* its corresponding location during the resize and thus should not be
|
|
* evicted. The array starts out cleared to zero. */
|
|
|
|
static inline gboolean
|
|
get_status_bit (const guint32 *bitmap, guint index)
|
|
{
|
|
return (bitmap[index / 32] >> (index % 32)) & 1;
|
|
}
|
|
|
|
static inline void
|
|
set_status_bit (guint32 *bitmap, guint index)
|
|
{
|
|
bitmap[index / 32] |= 1U << (index % 32);
|
|
}
|
|
|
|
/* By calling dedicated resize functions for sets and maps, we avoid 2x
|
|
* test-and-branch per key in the inner loop. This yields a small
|
|
* performance improvement at the cost of a bit of macro gunk. */
|
|
|
|
#define DEFINE_RESIZE_FUNC(fname) \
|
|
static void fname (GHashTable *hash_table, guint old_size, guint32 *reallocated_buckets_bitmap) \
|
|
{ \
|
|
guint i; \
|
|
\
|
|
for (i = 0; i < old_size; i++) \
|
|
{ \
|
|
guint node_hash = hash_table->hashes[i]; \
|
|
gpointer key, value G_GNUC_UNUSED; \
|
|
\
|
|
if (!HASH_IS_REAL (node_hash)) \
|
|
{ \
|
|
/* Clear tombstones */ \
|
|
hash_table->hashes[i] = UNUSED_HASH_VALUE; \
|
|
continue; \
|
|
} \
|
|
\
|
|
/* Skip entries relocated through eviction */ \
|
|
if (get_status_bit (reallocated_buckets_bitmap, i)) \
|
|
continue; \
|
|
\
|
|
hash_table->hashes[i] = UNUSED_HASH_VALUE; \
|
|
EVICT_KEYVAL (hash_table, i, NULL, NULL, key, value); \
|
|
\
|
|
for (;;) \
|
|
{ \
|
|
guint hash_val; \
|
|
guint replaced_hash; \
|
|
guint step = 0; \
|
|
\
|
|
hash_val = g_hash_table_hash_to_index (hash_table, node_hash); \
|
|
\
|
|
while (get_status_bit (reallocated_buckets_bitmap, hash_val)) \
|
|
{ \
|
|
step++; \
|
|
hash_val += step; \
|
|
hash_val &= hash_table->mask; \
|
|
} \
|
|
\
|
|
set_status_bit (reallocated_buckets_bitmap, hash_val); \
|
|
\
|
|
replaced_hash = hash_table->hashes[hash_val]; \
|
|
hash_table->hashes[hash_val] = node_hash; \
|
|
if (!HASH_IS_REAL (replaced_hash)) \
|
|
{ \
|
|
ASSIGN_KEYVAL (hash_table, hash_val, key, value); \
|
|
break; \
|
|
} \
|
|
\
|
|
node_hash = replaced_hash; \
|
|
EVICT_KEYVAL (hash_table, hash_val, key, value, key, value); \
|
|
} \
|
|
} \
|
|
}
|
|
|
|
#define ASSIGN_KEYVAL(ht, index, key, value) G_STMT_START{ \
|
|
g_hash_table_assign_key_or_value ((ht)->keys, (index), (ht)->have_big_keys, (key)); \
|
|
g_hash_table_assign_key_or_value ((ht)->values, (index), (ht)->have_big_values, (value)); \
|
|
}G_STMT_END
|
|
|
|
#define EVICT_KEYVAL(ht, index, key, value, outkey, outvalue) G_STMT_START{ \
|
|
(outkey) = g_hash_table_evict_key_or_value ((ht)->keys, (index), (ht)->have_big_keys, (key)); \
|
|
(outvalue) = g_hash_table_evict_key_or_value ((ht)->values, (index), (ht)->have_big_values, (value)); \
|
|
}G_STMT_END
|
|
|
|
DEFINE_RESIZE_FUNC (resize_map)
|
|
|
|
#undef ASSIGN_KEYVAL
|
|
#undef EVICT_KEYVAL
|
|
|
|
#define ASSIGN_KEYVAL(ht, index, key, value) G_STMT_START{ \
|
|
g_hash_table_assign_key_or_value ((ht)->keys, (index), (ht)->have_big_keys, (key)); \
|
|
}G_STMT_END
|
|
|
|
#define EVICT_KEYVAL(ht, index, key, value, outkey, outvalue) G_STMT_START{ \
|
|
(outkey) = g_hash_table_evict_key_or_value ((ht)->keys, (index), (ht)->have_big_keys, (key)); \
|
|
}G_STMT_END
|
|
|
|
DEFINE_RESIZE_FUNC (resize_set)
|
|
|
|
#undef ASSIGN_KEYVAL
|
|
#undef EVICT_KEYVAL
|
|
|
|
/*
|
|
* g_hash_table_resize:
|
|
* @hash_table: our #GHashTable
|
|
*
|
|
* Resizes the hash table to the optimal size based on the number of
|
|
* nodes currently held. If you call this function then a resize will
|
|
* occur, even if one does not need to occur.
|
|
* Use g_hash_table_maybe_resize() instead.
|
|
*
|
|
* This function may "resize" the hash table to its current size, with
|
|
* the side effect of cleaning up tombstones and otherwise optimizing
|
|
* the probe sequences.
|
|
*/
|
|
static void
|
|
g_hash_table_resize (GHashTable *hash_table)
|
|
{
|
|
guint32 *reallocated_buckets_bitmap;
|
|
gsize old_size;
|
|
gboolean is_a_set;
|
|
|
|
old_size = hash_table->size;
|
|
is_a_set = hash_table->keys == hash_table->values;
|
|
|
|
/* The outer checks in g_hash_table_maybe_resize() will only consider
|
|
* cleanup/resize when the load factor goes below .25 (1/4, ignoring
|
|
* tombstones) or above .9375 (15/16, including tombstones).
|
|
*
|
|
* Once this happens, tombstones will always be cleaned out. If our
|
|
* load sans tombstones is greater than .75 (1/1.333, see below), we'll
|
|
* take this opportunity to grow the table too.
|
|
*
|
|
* Immediately after growing, the load factor will be in the range
|
|
* .375 .. .469. After shrinking, it will be exactly .5. */
|
|
|
|
g_hash_table_set_shift_from_size (hash_table, hash_table->nnodes * 1.333);
|
|
|
|
if (hash_table->size > old_size)
|
|
{
|
|
realloc_arrays (hash_table, is_a_set);
|
|
memset (&hash_table->hashes[old_size], 0, (hash_table->size - old_size) * sizeof (guint));
|
|
|
|
reallocated_buckets_bitmap = g_new0 (guint32, (hash_table->size + 31) / 32);
|
|
}
|
|
else
|
|
{
|
|
reallocated_buckets_bitmap = g_new0 (guint32, (old_size + 31) / 32);
|
|
}
|
|
|
|
if (is_a_set)
|
|
resize_set (hash_table, old_size, reallocated_buckets_bitmap);
|
|
else
|
|
resize_map (hash_table, old_size, reallocated_buckets_bitmap);
|
|
|
|
g_free (reallocated_buckets_bitmap);
|
|
|
|
if (hash_table->size < old_size)
|
|
realloc_arrays (hash_table, is_a_set);
|
|
|
|
hash_table->noccupied = hash_table->nnodes;
|
|
}
|
|
|
|
/*
|
|
* g_hash_table_maybe_resize:
|
|
* @hash_table: our #GHashTable
|
|
*
|
|
* Resizes the hash table, if needed.
|
|
*
|
|
* Essentially, calls g_hash_table_resize() if the table has strayed
|
|
* too far from its ideal size for its number of nodes.
|
|
*/
|
|
static inline void
|
|
g_hash_table_maybe_resize (GHashTable *hash_table)
|
|
{
|
|
gint noccupied = hash_table->noccupied;
|
|
gint size = hash_table->size;
|
|
|
|
if ((size > hash_table->nnodes * 4 && size > 1 << HASH_TABLE_MIN_SHIFT) ||
|
|
(size <= noccupied + (noccupied / 16)))
|
|
g_hash_table_resize (hash_table);
|
|
}
|
|
|
|
#ifdef USE_SMALL_ARRAYS
|
|
|
|
static inline gboolean
|
|
entry_is_big (gpointer v)
|
|
{
|
|
return (((guintptr) v) >> ((BIG_ENTRY_SIZE - SMALL_ENTRY_SIZE) * 8)) != 0;
|
|
}
|
|
|
|
static inline gboolean
|
|
g_hash_table_maybe_make_big_keys_or_values (gpointer *a_p, gpointer v, gint ht_size)
|
|
{
|
|
if (entry_is_big (v))
|
|
{
|
|
guint *a = (guint *) *a_p;
|
|
gpointer *a_new;
|
|
gint i;
|
|
|
|
a_new = g_new (gpointer, ht_size);
|
|
|
|
for (i = 0; i < ht_size; i++)
|
|
{
|
|
a_new[i] = GUINT_TO_POINTER (a[i]);
|
|
}
|
|
|
|
g_free (a);
|
|
*a_p = a_new;
|
|
return TRUE;
|
|
}
|
|
|
|
return FALSE;
|
|
}
|
|
|
|
#endif
|
|
|
|
static inline void
|
|
g_hash_table_ensure_keyval_fits (GHashTable *hash_table, gpointer key, gpointer value)
|
|
{
|
|
gboolean is_a_set = (hash_table->keys == hash_table->values);
|
|
|
|
#ifdef USE_SMALL_ARRAYS
|
|
|
|
/* Convert from set to map? */
|
|
if (is_a_set)
|
|
{
|
|
if (hash_table->have_big_keys)
|
|
{
|
|
if (key != value)
|
|
hash_table->values = g_memdup (hash_table->keys, sizeof (gpointer) * hash_table->size);
|
|
/* Keys and values are both big now, so no need for further checks */
|
|
return;
|
|
}
|
|
else
|
|
{
|
|
if (key != value)
|
|
{
|
|
hash_table->values = g_memdup (hash_table->keys, sizeof (guint) * hash_table->size);
|
|
is_a_set = FALSE;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Make keys big? */
|
|
if (!hash_table->have_big_keys)
|
|
{
|
|
hash_table->have_big_keys = g_hash_table_maybe_make_big_keys_or_values (&hash_table->keys, key, hash_table->size);
|
|
|
|
if (is_a_set)
|
|
{
|
|
hash_table->values = hash_table->keys;
|
|
hash_table->have_big_values = hash_table->have_big_keys;
|
|
}
|
|
}
|
|
|
|
/* Make values big? */
|
|
if (!is_a_set && !hash_table->have_big_values)
|
|
{
|
|
hash_table->have_big_values = g_hash_table_maybe_make_big_keys_or_values (&hash_table->values, value, hash_table->size);
|
|
}
|
|
|
|
#else
|
|
|
|
/* Just split if necessary */
|
|
if (is_a_set && key != value)
|
|
hash_table->values = g_memdup (hash_table->keys, sizeof (gpointer) * hash_table->size);
|
|
|
|
#endif
|
|
}
|
|
|
|
/**
|
|
* g_hash_table_new:
|
|
* @hash_func: a function to create a hash value from a key
|
|
* @key_equal_func: a function to check two keys for equality
|
|
*
|
|
* Creates a new #GHashTable with a reference count of 1.
|
|
*
|
|
* Hash values returned by @hash_func are used to determine where keys
|
|
* are stored within the #GHashTable data structure. The g_direct_hash(),
|
|
* g_int_hash(), g_int64_hash(), g_double_hash() and g_str_hash()
|
|
* functions are provided for some common types of keys.
|
|
* If @hash_func is %NULL, g_direct_hash() is used.
|
|
*
|
|
* @key_equal_func is used when looking up keys in the #GHashTable.
|
|
* The g_direct_equal(), g_int_equal(), g_int64_equal(), g_double_equal()
|
|
* and g_str_equal() functions are provided for the most common types
|
|
* of keys. If @key_equal_func is %NULL, keys are compared directly in
|
|
* a similar fashion to g_direct_equal(), but without the overhead of
|
|
* a function call. @key_equal_func is called with the key from the hash table
|
|
* as its first parameter, and the user-provided key to check against as
|
|
* its second.
|
|
*
|
|
* Returns: a new #GHashTable
|
|
*/
|
|
GHashTable *
|
|
g_hash_table_new (GHashFunc hash_func,
|
|
GEqualFunc key_equal_func)
|
|
{
|
|
return g_hash_table_new_full (hash_func, key_equal_func, NULL, NULL);
|
|
}
|
|
|
|
|
|
/**
|
|
* g_hash_table_new_full:
|
|
* @hash_func: a function to create a hash value from a key
|
|
* @key_equal_func: a function to check two keys for equality
|
|
* @key_destroy_func: (nullable): a function to free the memory allocated for the key
|
|
* used when removing the entry from the #GHashTable, or %NULL
|
|
* if you don't want to supply such a function.
|
|
* @value_destroy_func: (nullable): a function to free the memory allocated for the
|
|
* value used when removing the entry from the #GHashTable, or %NULL
|
|
* if you don't want to supply such a function.
|
|
*
|
|
* Creates a new #GHashTable like g_hash_table_new() with a reference
|
|
* count of 1 and allows to specify functions to free the memory
|
|
* allocated for the key and value that get called when removing the
|
|
* entry from the #GHashTable.
|
|
*
|
|
* Since version 2.42 it is permissible for destroy notify functions to
|
|
* recursively remove further items from the hash table. This is only
|
|
* permissible if the application still holds a reference to the hash table.
|
|
* This means that you may need to ensure that the hash table is empty by
|
|
* calling g_hash_table_remove_all() before releasing the last reference using
|
|
* g_hash_table_unref().
|
|
*
|
|
* Returns: a new #GHashTable
|
|
*/
|
|
GHashTable *
|
|
g_hash_table_new_full (GHashFunc hash_func,
|
|
GEqualFunc key_equal_func,
|
|
GDestroyNotify key_destroy_func,
|
|
GDestroyNotify value_destroy_func)
|
|
{
|
|
GHashTable *hash_table;
|
|
|
|
hash_table = g_slice_new (GHashTable);
|
|
g_atomic_ref_count_init (&hash_table->ref_count);
|
|
hash_table->nnodes = 0;
|
|
hash_table->noccupied = 0;
|
|
hash_table->hash_func = hash_func ? hash_func : g_direct_hash;
|
|
hash_table->key_equal_func = key_equal_func;
|
|
#ifndef G_DISABLE_ASSERT
|
|
hash_table->version = 0;
|
|
#endif
|
|
hash_table->key_destroy_func = key_destroy_func;
|
|
hash_table->value_destroy_func = value_destroy_func;
|
|
|
|
g_hash_table_setup_storage (hash_table);
|
|
|
|
return hash_table;
|
|
}
|
|
|
|
/**
|
|
* g_hash_table_iter_init:
|
|
* @iter: an uninitialized #GHashTableIter
|
|
* @hash_table: a #GHashTable
|
|
*
|
|
* Initializes a key/value pair iterator and associates it with
|
|
* @hash_table. Modifying the hash table after calling this function
|
|
* invalidates the returned iterator.
|
|
* |[<!-- language="C" -->
|
|
* GHashTableIter iter;
|
|
* gpointer key, value;
|
|
*
|
|
* g_hash_table_iter_init (&iter, hash_table);
|
|
* while (g_hash_table_iter_next (&iter, &key, &value))
|
|
* {
|
|
* // do something with key and value
|
|
* }
|
|
* ]|
|
|
*
|
|
* Since: 2.16
|
|
*/
|
|
void
|
|
g_hash_table_iter_init (GHashTableIter *iter,
|
|
GHashTable *hash_table)
|
|
{
|
|
RealIter *ri = (RealIter *) iter;
|
|
|
|
g_return_if_fail (iter != NULL);
|
|
g_return_if_fail (hash_table != NULL);
|
|
|
|
ri->hash_table = hash_table;
|
|
ri->position = -1;
|
|
#ifndef G_DISABLE_ASSERT
|
|
ri->version = hash_table->version;
|
|
#endif
|
|
}
|
|
|
|
/**
|
|
* g_hash_table_iter_next:
|
|
* @iter: an initialized #GHashTableIter
|
|
* @key: (out) (optional): a location to store the key
|
|
* @value: (out) (optional) (nullable): a location to store the value
|
|
*
|
|
* Advances @iter and retrieves the key and/or value that are now
|
|
* pointed to as a result of this advancement. If %FALSE is returned,
|
|
* @key and @value are not set, and the iterator becomes invalid.
|
|
*
|
|
* Returns: %FALSE if the end of the #GHashTable has been reached.
|
|
*
|
|
* Since: 2.16
|
|
*/
|
|
gboolean
|
|
g_hash_table_iter_next (GHashTableIter *iter,
|
|
gpointer *key,
|
|
gpointer *value)
|
|
{
|
|
RealIter *ri = (RealIter *) iter;
|
|
gint position;
|
|
|
|
g_return_val_if_fail (iter != NULL, FALSE);
|
|
#ifndef G_DISABLE_ASSERT
|
|
g_return_val_if_fail (ri->version == ri->hash_table->version, FALSE);
|
|
#endif
|
|
g_return_val_if_fail (ri->position < (gssize) ri->hash_table->size, FALSE);
|
|
|
|
position = ri->position;
|
|
|
|
do
|
|
{
|
|
position++;
|
|
if (position >= (gssize) ri->hash_table->size)
|
|
{
|
|
ri->position = position;
|
|
return FALSE;
|
|
}
|
|
}
|
|
while (!HASH_IS_REAL (ri->hash_table->hashes[position]));
|
|
|
|
if (key != NULL)
|
|
*key = g_hash_table_fetch_key_or_value (ri->hash_table->keys, position, ri->hash_table->have_big_keys);
|
|
if (value != NULL)
|
|
*value = g_hash_table_fetch_key_or_value (ri->hash_table->values, position, ri->hash_table->have_big_values);
|
|
|
|
ri->position = position;
|
|
return TRUE;
|
|
}
|
|
|
|
/**
|
|
* g_hash_table_iter_get_hash_table:
|
|
* @iter: an initialized #GHashTableIter
|
|
*
|
|
* Returns the #GHashTable associated with @iter.
|
|
*
|
|
* Returns: the #GHashTable associated with @iter.
|
|
*
|
|
* Since: 2.16
|
|
*/
|
|
GHashTable *
|
|
g_hash_table_iter_get_hash_table (GHashTableIter *iter)
|
|
{
|
|
g_return_val_if_fail (iter != NULL, NULL);
|
|
|
|
return ((RealIter *) iter)->hash_table;
|
|
}
|
|
|
|
static void
|
|
iter_remove_or_steal (RealIter *ri, gboolean notify)
|
|
{
|
|
g_return_if_fail (ri != NULL);
|
|
#ifndef G_DISABLE_ASSERT
|
|
g_return_if_fail (ri->version == ri->hash_table->version);
|
|
#endif
|
|
g_return_if_fail (ri->position >= 0);
|
|
g_return_if_fail ((gsize) ri->position < ri->hash_table->size);
|
|
|
|
g_hash_table_remove_node (ri->hash_table, ri->position, notify);
|
|
|
|
#ifndef G_DISABLE_ASSERT
|
|
ri->version++;
|
|
ri->hash_table->version++;
|
|
#endif
|
|
}
|
|
|
|
/**
|
|
* g_hash_table_iter_remove:
|
|
* @iter: an initialized #GHashTableIter
|
|
*
|
|
* Removes the key/value pair currently pointed to by the iterator
|
|
* from its associated #GHashTable. Can only be called after
|
|
* g_hash_table_iter_next() returned %TRUE, and cannot be called
|
|
* more than once for the same key/value pair.
|
|
*
|
|
* If the #GHashTable was created using g_hash_table_new_full(),
|
|
* the key and value are freed using the supplied destroy functions,
|
|
* otherwise you have to make sure that any dynamically allocated
|
|
* values are freed yourself.
|
|
*
|
|
* It is safe to continue iterating the #GHashTable afterward:
|
|
* |[<!-- language="C" -->
|
|
* while (g_hash_table_iter_next (&iter, &key, &value))
|
|
* {
|
|
* if (condition)
|
|
* g_hash_table_iter_remove (&iter);
|
|
* }
|
|
* ]|
|
|
*
|
|
* Since: 2.16
|
|
*/
|
|
void
|
|
g_hash_table_iter_remove (GHashTableIter *iter)
|
|
{
|
|
iter_remove_or_steal ((RealIter *) iter, TRUE);
|
|
}
|
|
|
|
/*
|
|
* g_hash_table_insert_node:
|
|
* @hash_table: our #GHashTable
|
|
* @node_index: pointer to node to insert/replace
|
|
* @key_hash: key hash
|
|
* @key: (nullable): key to replace with, or %NULL
|
|
* @value: value to replace with
|
|
* @keep_new_key: whether to replace the key in the node with @key
|
|
* @reusing_key: whether @key was taken out of the existing node
|
|
*
|
|
* Inserts a value at @node_index in the hash table and updates it.
|
|
*
|
|
* If @key has been taken out of the existing node (ie it is not
|
|
* passed in via a g_hash_table_insert/replace) call, then @reusing_key
|
|
* should be %TRUE.
|
|
*
|
|
* Returns: %TRUE if the key did not exist yet
|
|
*/
|
|
static gboolean
|
|
g_hash_table_insert_node (GHashTable *hash_table,
|
|
guint node_index,
|
|
guint key_hash,
|
|
gpointer new_key,
|
|
gpointer new_value,
|
|
gboolean keep_new_key,
|
|
gboolean reusing_key)
|
|
{
|
|
gboolean already_exists;
|
|
guint old_hash;
|
|
gpointer key_to_free = NULL;
|
|
gpointer key_to_keep = NULL;
|
|
gpointer value_to_free = NULL;
|
|
|
|
old_hash = hash_table->hashes[node_index];
|
|
already_exists = HASH_IS_REAL (old_hash);
|
|
|
|
/* Proceed in three steps. First, deal with the key because it is the
|
|
* most complicated. Then consider if we need to split the table in
|
|
* two (because writing the value will result in the set invariant
|
|
* becoming broken). Then deal with the value.
|
|
*
|
|
* There are three cases for the key:
|
|
*
|
|
* - entry already exists in table, reusing key:
|
|
* free the just-passed-in new_key and use the existing value
|
|
*
|
|
* - entry already exists in table, not reusing key:
|
|
* free the entry in the table, use the new key
|
|
*
|
|
* - entry not already in table:
|
|
* use the new key, free nothing
|
|
*
|
|
* We update the hash at the same time...
|
|
*/
|
|
if (already_exists)
|
|
{
|
|
/* Note: we must record the old value before writing the new key
|
|
* because we might change the value in the event that the two
|
|
* arrays are shared.
|
|
*/
|
|
value_to_free = g_hash_table_fetch_key_or_value (hash_table->values, node_index, hash_table->have_big_values);
|
|
|
|
if (keep_new_key)
|
|
{
|
|
key_to_free = g_hash_table_fetch_key_or_value (hash_table->keys, node_index, hash_table->have_big_keys);
|
|
key_to_keep = new_key;
|
|
}
|
|
else
|
|
{
|
|
key_to_free = new_key;
|
|
key_to_keep = g_hash_table_fetch_key_or_value (hash_table->keys, node_index, hash_table->have_big_keys);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
hash_table->hashes[node_index] = key_hash;
|
|
key_to_keep = new_key;
|
|
}
|
|
|
|
/* Resize key/value arrays and split table as necessary */
|
|
g_hash_table_ensure_keyval_fits (hash_table, key_to_keep, new_value);
|
|
g_hash_table_assign_key_or_value (hash_table->keys, node_index, hash_table->have_big_keys, key_to_keep);
|
|
|
|
/* Step 3: Actually do the write */
|
|
g_hash_table_assign_key_or_value (hash_table->values, node_index, hash_table->have_big_values, new_value);
|
|
|
|
/* Now, the bookkeeping... */
|
|
if (!already_exists)
|
|
{
|
|
hash_table->nnodes++;
|
|
|
|
if (HASH_IS_UNUSED (old_hash))
|
|
{
|
|
/* We replaced an empty node, and not a tombstone */
|
|
hash_table->noccupied++;
|
|
g_hash_table_maybe_resize (hash_table);
|
|
}
|
|
|
|
#ifndef G_DISABLE_ASSERT
|
|
hash_table->version++;
|
|
#endif
|
|
}
|
|
|
|
if (already_exists)
|
|
{
|
|
if (hash_table->key_destroy_func && !reusing_key)
|
|
(* hash_table->key_destroy_func) (key_to_free);
|
|
if (hash_table->value_destroy_func)
|
|
(* hash_table->value_destroy_func) (value_to_free);
|
|
}
|
|
|
|
return !already_exists;
|
|
}
|
|
|
|
/**
|
|
* g_hash_table_iter_replace:
|
|
* @iter: an initialized #GHashTableIter
|
|
* @value: the value to replace with
|
|
*
|
|
* Replaces the value currently pointed to by the iterator
|
|
* from its associated #GHashTable. Can only be called after
|
|
* g_hash_table_iter_next() returned %TRUE.
|
|
*
|
|
* If you supplied a @value_destroy_func when creating the
|
|
* #GHashTable, the old value is freed using that function.
|
|
*
|
|
* Since: 2.30
|
|
*/
|
|
void
|
|
g_hash_table_iter_replace (GHashTableIter *iter,
|
|
gpointer value)
|
|
{
|
|
RealIter *ri;
|
|
guint node_hash;
|
|
gpointer key;
|
|
|
|
ri = (RealIter *) iter;
|
|
|
|
g_return_if_fail (ri != NULL);
|
|
#ifndef G_DISABLE_ASSERT
|
|
g_return_if_fail (ri->version == ri->hash_table->version);
|
|
#endif
|
|
g_return_if_fail (ri->position >= 0);
|
|
g_return_if_fail ((gsize) ri->position < ri->hash_table->size);
|
|
|
|
node_hash = ri->hash_table->hashes[ri->position];
|
|
|
|
key = g_hash_table_fetch_key_or_value (ri->hash_table->keys, ri->position, ri->hash_table->have_big_keys);
|
|
|
|
g_hash_table_insert_node (ri->hash_table, ri->position, node_hash, key, value, TRUE, TRUE);
|
|
|
|
#ifndef G_DISABLE_ASSERT
|
|
ri->version++;
|
|
ri->hash_table->version++;
|
|
#endif
|
|
}
|
|
|
|
/**
|
|
* g_hash_table_iter_steal:
|
|
* @iter: an initialized #GHashTableIter
|
|
*
|
|
* Removes the key/value pair currently pointed to by the
|
|
* iterator from its associated #GHashTable, without calling
|
|
* the key and value destroy functions. Can only be called
|
|
* after g_hash_table_iter_next() returned %TRUE, and cannot
|
|
* be called more than once for the same key/value pair.
|
|
*
|
|
* Since: 2.16
|
|
*/
|
|
void
|
|
g_hash_table_iter_steal (GHashTableIter *iter)
|
|
{
|
|
iter_remove_or_steal ((RealIter *) iter, FALSE);
|
|
}
|
|
|
|
|
|
/**
|
|
* g_hash_table_ref:
|
|
* @hash_table: a valid #GHashTable
|
|
*
|
|
* Atomically increments the reference count of @hash_table by one.
|
|
* This function is MT-safe and may be called from any thread.
|
|
*
|
|
* Returns: the passed in #GHashTable
|
|
*
|
|
* Since: 2.10
|
|
*/
|
|
GHashTable *
|
|
g_hash_table_ref (GHashTable *hash_table)
|
|
{
|
|
g_return_val_if_fail (hash_table != NULL, NULL);
|
|
|
|
g_atomic_ref_count_inc (&hash_table->ref_count);
|
|
|
|
return hash_table;
|
|
}
|
|
|
|
/**
|
|
* g_hash_table_unref:
|
|
* @hash_table: a valid #GHashTable
|
|
*
|
|
* Atomically decrements the reference count of @hash_table by one.
|
|
* If the reference count drops to 0, all keys and values will be
|
|
* destroyed, and all memory allocated by the hash table is released.
|
|
* This function is MT-safe and may be called from any thread.
|
|
*
|
|
* Since: 2.10
|
|
*/
|
|
void
|
|
g_hash_table_unref (GHashTable *hash_table)
|
|
{
|
|
g_return_if_fail (hash_table != NULL);
|
|
|
|
if (g_atomic_ref_count_dec (&hash_table->ref_count))
|
|
{
|
|
g_hash_table_remove_all_nodes (hash_table, TRUE, TRUE);
|
|
if (hash_table->keys != hash_table->values)
|
|
g_free (hash_table->values);
|
|
g_free (hash_table->keys);
|
|
g_free (hash_table->hashes);
|
|
g_slice_free (GHashTable, hash_table);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* g_hash_table_destroy:
|
|
* @hash_table: a #GHashTable
|
|
*
|
|
* Destroys all keys and values in the #GHashTable and decrements its
|
|
* reference count by 1. If keys and/or values are dynamically allocated,
|
|
* you should either free them first or create the #GHashTable with destroy
|
|
* notifiers using g_hash_table_new_full(). In the latter case the destroy
|
|
* functions you supplied will be called on all keys and values during the
|
|
* destruction phase.
|
|
*/
|
|
void
|
|
g_hash_table_destroy (GHashTable *hash_table)
|
|
{
|
|
g_return_if_fail (hash_table != NULL);
|
|
|
|
g_hash_table_remove_all (hash_table);
|
|
g_hash_table_unref (hash_table);
|
|
}
|
|
|
|
/**
|
|
* g_hash_table_lookup:
|
|
* @hash_table: a #GHashTable
|
|
* @key: the key to look up
|
|
*
|
|
* Looks up a key in a #GHashTable. Note that this function cannot
|
|
* distinguish between a key that is not present and one which is present
|
|
* and has the value %NULL. If you need this distinction, use
|
|
* g_hash_table_lookup_extended().
|
|
*
|
|
* Returns: (nullable): the associated value, or %NULL if the key is not found
|
|
*/
|
|
gpointer
|
|
g_hash_table_lookup (GHashTable *hash_table,
|
|
gconstpointer key)
|
|
{
|
|
guint node_index;
|
|
guint node_hash;
|
|
|
|
g_return_val_if_fail (hash_table != NULL, NULL);
|
|
|
|
node_index = g_hash_table_lookup_node (hash_table, key, &node_hash);
|
|
|
|
return HASH_IS_REAL (hash_table->hashes[node_index])
|
|
? g_hash_table_fetch_key_or_value (hash_table->values, node_index, hash_table->have_big_values)
|
|
: NULL;
|
|
}
|
|
|
|
/**
|
|
* g_hash_table_lookup_extended:
|
|
* @hash_table: a #GHashTable
|
|
* @lookup_key: the key to look up
|
|
* @orig_key: (out) (optional): return location for the original key
|
|
* @value: (out) (optional) (nullable): return location for the value associated
|
|
* with the key
|
|
*
|
|
* Looks up a key in the #GHashTable, returning the original key and the
|
|
* associated value and a #gboolean which is %TRUE if the key was found. This
|
|
* is useful if you need to free the memory allocated for the original key,
|
|
* for example before calling g_hash_table_remove().
|
|
*
|
|
* You can actually pass %NULL for @lookup_key to test
|
|
* whether the %NULL key exists, provided the hash and equal functions
|
|
* of @hash_table are %NULL-safe.
|
|
*
|
|
* Returns: %TRUE if the key was found in the #GHashTable
|
|
*/
|
|
gboolean
|
|
g_hash_table_lookup_extended (GHashTable *hash_table,
|
|
gconstpointer lookup_key,
|
|
gpointer *orig_key,
|
|
gpointer *value)
|
|
{
|
|
guint node_index;
|
|
guint node_hash;
|
|
|
|
g_return_val_if_fail (hash_table != NULL, FALSE);
|
|
|
|
node_index = g_hash_table_lookup_node (hash_table, lookup_key, &node_hash);
|
|
|
|
if (!HASH_IS_REAL (hash_table->hashes[node_index]))
|
|
{
|
|
if (orig_key != NULL)
|
|
*orig_key = NULL;
|
|
if (value != NULL)
|
|
*value = NULL;
|
|
|
|
return FALSE;
|
|
}
|
|
|
|
if (orig_key)
|
|
*orig_key = g_hash_table_fetch_key_or_value (hash_table->keys, node_index, hash_table->have_big_keys);
|
|
|
|
if (value)
|
|
*value = g_hash_table_fetch_key_or_value (hash_table->values, node_index, hash_table->have_big_values);
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
/*
|
|
* g_hash_table_insert_internal:
|
|
* @hash_table: our #GHashTable
|
|
* @key: the key to insert
|
|
* @value: the value to insert
|
|
* @keep_new_key: if %TRUE and this key already exists in the table
|
|
* then call the destroy notify function on the old key. If %FALSE
|
|
* then call the destroy notify function on the new key.
|
|
*
|
|
* Implements the common logic for the g_hash_table_insert() and
|
|
* g_hash_table_replace() functions.
|
|
*
|
|
* Do a lookup of @key. If it is found, replace it with the new
|
|
* @value (and perhaps the new @key). If it is not found, create
|
|
* a new node.
|
|
*
|
|
* Returns: %TRUE if the key did not exist yet
|
|
*/
|
|
static gboolean
|
|
g_hash_table_insert_internal (GHashTable *hash_table,
|
|
gpointer key,
|
|
gpointer value,
|
|
gboolean keep_new_key)
|
|
{
|
|
guint key_hash;
|
|
guint node_index;
|
|
|
|
g_return_val_if_fail (hash_table != NULL, FALSE);
|
|
|
|
node_index = g_hash_table_lookup_node (hash_table, key, &key_hash);
|
|
|
|
return g_hash_table_insert_node (hash_table, node_index, key_hash, key, value, keep_new_key, FALSE);
|
|
}
|
|
|
|
/**
|
|
* g_hash_table_insert:
|
|
* @hash_table: a #GHashTable
|
|
* @key: a key to insert
|
|
* @value: the value to associate with the key
|
|
*
|
|
* Inserts a new key and value into a #GHashTable.
|
|
*
|
|
* If the key already exists in the #GHashTable its current
|
|
* value is replaced with the new value. If you supplied a
|
|
* @value_destroy_func when creating the #GHashTable, the old
|
|
* value is freed using that function. If you supplied a
|
|
* @key_destroy_func when creating the #GHashTable, the passed
|
|
* key is freed using that function.
|
|
*
|
|
* Starting from GLib 2.40, this function returns a boolean value to
|
|
* indicate whether the newly added value was already in the hash table
|
|
* or not.
|
|
*
|
|
* Returns: %TRUE if the key did not exist yet
|
|
*/
|
|
gboolean
|
|
g_hash_table_insert (GHashTable *hash_table,
|
|
gpointer key,
|
|
gpointer value)
|
|
{
|
|
return g_hash_table_insert_internal (hash_table, key, value, FALSE);
|
|
}
|
|
|
|
/**
|
|
* g_hash_table_replace:
|
|
* @hash_table: a #GHashTable
|
|
* @key: a key to insert
|
|
* @value: the value to associate with the key
|
|
*
|
|
* Inserts a new key and value into a #GHashTable similar to
|
|
* g_hash_table_insert(). The difference is that if the key
|
|
* already exists in the #GHashTable, it gets replaced by the
|
|
* new key. If you supplied a @value_destroy_func when creating
|
|
* the #GHashTable, the old value is freed using that function.
|
|
* If you supplied a @key_destroy_func when creating the
|
|
* #GHashTable, the old key is freed using that function.
|
|
*
|
|
* Starting from GLib 2.40, this function returns a boolean value to
|
|
* indicate whether the newly added value was already in the hash table
|
|
* or not.
|
|
*
|
|
* Returns: %TRUE if the key did not exist yet
|
|
*/
|
|
gboolean
|
|
g_hash_table_replace (GHashTable *hash_table,
|
|
gpointer key,
|
|
gpointer value)
|
|
{
|
|
return g_hash_table_insert_internal (hash_table, key, value, TRUE);
|
|
}
|
|
|
|
/**
|
|
* g_hash_table_add:
|
|
* @hash_table: a #GHashTable
|
|
* @key: a key to insert
|
|
*
|
|
* This is a convenience function for using a #GHashTable as a set. It
|
|
* is equivalent to calling g_hash_table_replace() with @key as both the
|
|
* key and the value.
|
|
*
|
|
* When a hash table only ever contains keys that have themselves as the
|
|
* corresponding value it is able to be stored more efficiently. See
|
|
* the discussion in the section description.
|
|
*
|
|
* Starting from GLib 2.40, this function returns a boolean value to
|
|
* indicate whether the newly added value was already in the hash table
|
|
* or not.
|
|
*
|
|
* Returns: %TRUE if the key did not exist yet
|
|
*
|
|
* Since: 2.32
|
|
*/
|
|
gboolean
|
|
g_hash_table_add (GHashTable *hash_table,
|
|
gpointer key)
|
|
{
|
|
return g_hash_table_insert_internal (hash_table, key, key, TRUE);
|
|
}
|
|
|
|
/**
|
|
* g_hash_table_contains:
|
|
* @hash_table: a #GHashTable
|
|
* @key: a key to check
|
|
*
|
|
* Checks if @key is in @hash_table.
|
|
*
|
|
* Returns: %TRUE if @key is in @hash_table, %FALSE otherwise.
|
|
*
|
|
* Since: 2.32
|
|
**/
|
|
gboolean
|
|
g_hash_table_contains (GHashTable *hash_table,
|
|
gconstpointer key)
|
|
{
|
|
guint node_index;
|
|
guint node_hash;
|
|
|
|
g_return_val_if_fail (hash_table != NULL, FALSE);
|
|
|
|
node_index = g_hash_table_lookup_node (hash_table, key, &node_hash);
|
|
|
|
return HASH_IS_REAL (hash_table->hashes[node_index]);
|
|
}
|
|
|
|
/*
|
|
* g_hash_table_remove_internal:
|
|
* @hash_table: our #GHashTable
|
|
* @key: the key to remove
|
|
* @notify: %TRUE if the destroy notify handlers are to be called
|
|
* Returns: %TRUE if a node was found and removed, else %FALSE
|
|
*
|
|
* Implements the common logic for the g_hash_table_remove() and
|
|
* g_hash_table_steal() functions.
|
|
*
|
|
* Do a lookup of @key and remove it if it is found, calling the
|
|
* destroy notify handlers only if @notify is %TRUE.
|
|
*/
|
|
static gboolean
|
|
g_hash_table_remove_internal (GHashTable *hash_table,
|
|
gconstpointer key,
|
|
gboolean notify)
|
|
{
|
|
guint node_index;
|
|
guint node_hash;
|
|
|
|
g_return_val_if_fail (hash_table != NULL, FALSE);
|
|
|
|
node_index = g_hash_table_lookup_node (hash_table, key, &node_hash);
|
|
|
|
if (!HASH_IS_REAL (hash_table->hashes[node_index]))
|
|
return FALSE;
|
|
|
|
g_hash_table_remove_node (hash_table, node_index, notify);
|
|
g_hash_table_maybe_resize (hash_table);
|
|
|
|
#ifndef G_DISABLE_ASSERT
|
|
hash_table->version++;
|
|
#endif
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
/**
|
|
* g_hash_table_remove:
|
|
* @hash_table: a #GHashTable
|
|
* @key: the key to remove
|
|
*
|
|
* Removes a key and its associated value from a #GHashTable.
|
|
*
|
|
* If the #GHashTable was created using g_hash_table_new_full(), the
|
|
* key and value are freed using the supplied destroy functions, otherwise
|
|
* you have to make sure that any dynamically allocated values are freed
|
|
* yourself.
|
|
*
|
|
* Returns: %TRUE if the key was found and removed from the #GHashTable
|
|
*/
|
|
gboolean
|
|
g_hash_table_remove (GHashTable *hash_table,
|
|
gconstpointer key)
|
|
{
|
|
return g_hash_table_remove_internal (hash_table, key, TRUE);
|
|
}
|
|
|
|
/**
|
|
* g_hash_table_steal:
|
|
* @hash_table: a #GHashTable
|
|
* @key: the key to remove
|
|
*
|
|
* Removes a key and its associated value from a #GHashTable without
|
|
* calling the key and value destroy functions.
|
|
*
|
|
* Returns: %TRUE if the key was found and removed from the #GHashTable
|
|
*/
|
|
gboolean
|
|
g_hash_table_steal (GHashTable *hash_table,
|
|
gconstpointer key)
|
|
{
|
|
return g_hash_table_remove_internal (hash_table, key, FALSE);
|
|
}
|
|
|
|
/**
|
|
* g_hash_table_steal_extended:
|
|
* @hash_table: a #GHashTable
|
|
* @lookup_key: the key to look up
|
|
* @stolen_key: (out) (optional) (transfer full): return location for the
|
|
* original key
|
|
* @stolen_value: (out) (optional) (nullable) (transfer full): return location
|
|
* for the value associated with the key
|
|
*
|
|
* Looks up a key in the #GHashTable, stealing the original key and the
|
|
* associated value and returning %TRUE if the key was found. If the key was
|
|
* not found, %FALSE is returned.
|
|
*
|
|
* If found, the stolen key and value are removed from the hash table without
|
|
* calling the key and value destroy functions, and ownership is transferred to
|
|
* the caller of this method; as with g_hash_table_steal().
|
|
*
|
|
* You can pass %NULL for @lookup_key, provided the hash and equal functions
|
|
* of @hash_table are %NULL-safe.
|
|
*
|
|
* Returns: %TRUE if the key was found in the #GHashTable
|
|
* Since: 2.58
|
|
*/
|
|
gboolean
|
|
g_hash_table_steal_extended (GHashTable *hash_table,
|
|
gconstpointer lookup_key,
|
|
gpointer *stolen_key,
|
|
gpointer *stolen_value)
|
|
{
|
|
guint node_index;
|
|
guint node_hash;
|
|
|
|
g_return_val_if_fail (hash_table != NULL, FALSE);
|
|
|
|
node_index = g_hash_table_lookup_node (hash_table, lookup_key, &node_hash);
|
|
|
|
if (!HASH_IS_REAL (hash_table->hashes[node_index]))
|
|
{
|
|
if (stolen_key != NULL)
|
|
*stolen_key = NULL;
|
|
if (stolen_value != NULL)
|
|
*stolen_value = NULL;
|
|
return FALSE;
|
|
}
|
|
|
|
if (stolen_key != NULL)
|
|
{
|
|
*stolen_key = g_hash_table_fetch_key_or_value (hash_table->keys, node_index, hash_table->have_big_keys);
|
|
g_hash_table_assign_key_or_value (hash_table->keys, node_index, hash_table->have_big_keys, NULL);
|
|
}
|
|
|
|
if (stolen_value != NULL)
|
|
{
|
|
*stolen_value = g_hash_table_fetch_key_or_value (hash_table->values, node_index, hash_table->have_big_values);
|
|
g_hash_table_assign_key_or_value (hash_table->values, node_index, hash_table->have_big_values, NULL);
|
|
}
|
|
|
|
g_hash_table_remove_node (hash_table, node_index, FALSE);
|
|
g_hash_table_maybe_resize (hash_table);
|
|
|
|
#ifndef G_DISABLE_ASSERT
|
|
hash_table->version++;
|
|
#endif
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
/**
|
|
* g_hash_table_remove_all:
|
|
* @hash_table: a #GHashTable
|
|
*
|
|
* Removes all keys and their associated values from a #GHashTable.
|
|
*
|
|
* If the #GHashTable was created using g_hash_table_new_full(),
|
|
* the keys and values are freed using the supplied destroy functions,
|
|
* otherwise you have to make sure that any dynamically allocated
|
|
* values are freed yourself.
|
|
*
|
|
* Since: 2.12
|
|
*/
|
|
void
|
|
g_hash_table_remove_all (GHashTable *hash_table)
|
|
{
|
|
g_return_if_fail (hash_table != NULL);
|
|
|
|
#ifndef G_DISABLE_ASSERT
|
|
if (hash_table->nnodes != 0)
|
|
hash_table->version++;
|
|
#endif
|
|
|
|
g_hash_table_remove_all_nodes (hash_table, TRUE, FALSE);
|
|
g_hash_table_maybe_resize (hash_table);
|
|
}
|
|
|
|
/**
|
|
* g_hash_table_steal_all:
|
|
* @hash_table: a #GHashTable
|
|
*
|
|
* Removes all keys and their associated values from a #GHashTable
|
|
* without calling the key and value destroy functions.
|
|
*
|
|
* Since: 2.12
|
|
*/
|
|
void
|
|
g_hash_table_steal_all (GHashTable *hash_table)
|
|
{
|
|
g_return_if_fail (hash_table != NULL);
|
|
|
|
#ifndef G_DISABLE_ASSERT
|
|
if (hash_table->nnodes != 0)
|
|
hash_table->version++;
|
|
#endif
|
|
|
|
g_hash_table_remove_all_nodes (hash_table, FALSE, FALSE);
|
|
g_hash_table_maybe_resize (hash_table);
|
|
}
|
|
|
|
/*
|
|
* g_hash_table_foreach_remove_or_steal:
|
|
* @hash_table: a #GHashTable
|
|
* @func: the user's callback function
|
|
* @user_data: data for @func
|
|
* @notify: %TRUE if the destroy notify handlers are to be called
|
|
*
|
|
* Implements the common logic for g_hash_table_foreach_remove()
|
|
* and g_hash_table_foreach_steal().
|
|
*
|
|
* Iterates over every node in the table, calling @func with the key
|
|
* and value of the node (and @user_data). If @func returns %TRUE the
|
|
* node is removed from the table.
|
|
*
|
|
* If @notify is true then the destroy notify handlers will be called
|
|
* for each removed node.
|
|
*/
|
|
static guint
|
|
g_hash_table_foreach_remove_or_steal (GHashTable *hash_table,
|
|
GHRFunc func,
|
|
gpointer user_data,
|
|
gboolean notify)
|
|
{
|
|
guint deleted = 0;
|
|
gsize i;
|
|
#ifndef G_DISABLE_ASSERT
|
|
gint version = hash_table->version;
|
|
#endif
|
|
|
|
for (i = 0; i < hash_table->size; i++)
|
|
{
|
|
guint node_hash = hash_table->hashes[i];
|
|
gpointer node_key = g_hash_table_fetch_key_or_value (hash_table->keys, i, hash_table->have_big_keys);
|
|
gpointer node_value = g_hash_table_fetch_key_or_value (hash_table->values, i, hash_table->have_big_values);
|
|
|
|
if (HASH_IS_REAL (node_hash) &&
|
|
(* func) (node_key, node_value, user_data))
|
|
{
|
|
g_hash_table_remove_node (hash_table, i, notify);
|
|
deleted++;
|
|
}
|
|
|
|
#ifndef G_DISABLE_ASSERT
|
|
g_return_val_if_fail (version == hash_table->version, 0);
|
|
#endif
|
|
}
|
|
|
|
g_hash_table_maybe_resize (hash_table);
|
|
|
|
#ifndef G_DISABLE_ASSERT
|
|
if (deleted > 0)
|
|
hash_table->version++;
|
|
#endif
|
|
|
|
return deleted;
|
|
}
|
|
|
|
/**
|
|
* g_hash_table_foreach_remove:
|
|
* @hash_table: a #GHashTable
|
|
* @func: the function to call for each key/value pair
|
|
* @user_data: user data to pass to the function
|
|
*
|
|
* Calls the given function for each key/value pair in the
|
|
* #GHashTable. If the function returns %TRUE, then the key/value
|
|
* pair is removed from the #GHashTable. If you supplied key or
|
|
* value destroy functions when creating the #GHashTable, they are
|
|
* used to free the memory allocated for the removed keys and values.
|
|
*
|
|
* See #GHashTableIter for an alternative way to loop over the
|
|
* key/value pairs in the hash table.
|
|
*
|
|
* Returns: the number of key/value pairs removed
|
|
*/
|
|
guint
|
|
g_hash_table_foreach_remove (GHashTable *hash_table,
|
|
GHRFunc func,
|
|
gpointer user_data)
|
|
{
|
|
g_return_val_if_fail (hash_table != NULL, 0);
|
|
g_return_val_if_fail (func != NULL, 0);
|
|
|
|
return g_hash_table_foreach_remove_or_steal (hash_table, func, user_data, TRUE);
|
|
}
|
|
|
|
/**
|
|
* g_hash_table_foreach_steal:
|
|
* @hash_table: a #GHashTable
|
|
* @func: the function to call for each key/value pair
|
|
* @user_data: user data to pass to the function
|
|
*
|
|
* Calls the given function for each key/value pair in the
|
|
* #GHashTable. If the function returns %TRUE, then the key/value
|
|
* pair is removed from the #GHashTable, but no key or value
|
|
* destroy functions are called.
|
|
*
|
|
* See #GHashTableIter for an alternative way to loop over the
|
|
* key/value pairs in the hash table.
|
|
*
|
|
* Returns: the number of key/value pairs removed.
|
|
*/
|
|
guint
|
|
g_hash_table_foreach_steal (GHashTable *hash_table,
|
|
GHRFunc func,
|
|
gpointer user_data)
|
|
{
|
|
g_return_val_if_fail (hash_table != NULL, 0);
|
|
g_return_val_if_fail (func != NULL, 0);
|
|
|
|
return g_hash_table_foreach_remove_or_steal (hash_table, func, user_data, FALSE);
|
|
}
|
|
|
|
/**
|
|
* g_hash_table_foreach:
|
|
* @hash_table: a #GHashTable
|
|
* @func: the function to call for each key/value pair
|
|
* @user_data: user data to pass to the function
|
|
*
|
|
* Calls the given function for each of the key/value pairs in the
|
|
* #GHashTable. The function is passed the key and value of each
|
|
* pair, and the given @user_data parameter. The hash table may not
|
|
* be modified while iterating over it (you can't add/remove
|
|
* items). To remove all items matching a predicate, use
|
|
* g_hash_table_foreach_remove().
|
|
*
|
|
* See g_hash_table_find() for performance caveats for linear
|
|
* order searches in contrast to g_hash_table_lookup().
|
|
*/
|
|
void
|
|
g_hash_table_foreach (GHashTable *hash_table,
|
|
GHFunc func,
|
|
gpointer user_data)
|
|
{
|
|
gsize i;
|
|
#ifndef G_DISABLE_ASSERT
|
|
gint version;
|
|
#endif
|
|
|
|
g_return_if_fail (hash_table != NULL);
|
|
g_return_if_fail (func != NULL);
|
|
|
|
#ifndef G_DISABLE_ASSERT
|
|
version = hash_table->version;
|
|
#endif
|
|
|
|
for (i = 0; i < hash_table->size; i++)
|
|
{
|
|
guint node_hash = hash_table->hashes[i];
|
|
gpointer node_key = g_hash_table_fetch_key_or_value (hash_table->keys, i, hash_table->have_big_keys);
|
|
gpointer node_value = g_hash_table_fetch_key_or_value (hash_table->values, i, hash_table->have_big_values);
|
|
|
|
if (HASH_IS_REAL (node_hash))
|
|
(* func) (node_key, node_value, user_data);
|
|
|
|
#ifndef G_DISABLE_ASSERT
|
|
g_return_if_fail (version == hash_table->version);
|
|
#endif
|
|
}
|
|
}
|
|
|
|
/**
|
|
* g_hash_table_find:
|
|
* @hash_table: a #GHashTable
|
|
* @predicate: function to test the key/value pairs for a certain property
|
|
* @user_data: user data to pass to the function
|
|
*
|
|
* Calls the given function for key/value pairs in the #GHashTable
|
|
* until @predicate returns %TRUE. The function is passed the key
|
|
* and value of each pair, and the given @user_data parameter. The
|
|
* hash table may not be modified while iterating over it (you can't
|
|
* add/remove items).
|
|
*
|
|
* Note, that hash tables are really only optimized for forward
|
|
* lookups, i.e. g_hash_table_lookup(). So code that frequently issues
|
|
* g_hash_table_find() or g_hash_table_foreach() (e.g. in the order of
|
|
* once per every entry in a hash table) should probably be reworked
|
|
* to use additional or different data structures for reverse lookups
|
|
* (keep in mind that an O(n) find/foreach operation issued for all n
|
|
* values in a hash table ends up needing O(n*n) operations).
|
|
*
|
|
* Returns: (nullable): The value of the first key/value pair is returned,
|
|
* for which @predicate evaluates to %TRUE. If no pair with the
|
|
* requested property is found, %NULL is returned.
|
|
*
|
|
* Since: 2.4
|
|
*/
|
|
gpointer
|
|
g_hash_table_find (GHashTable *hash_table,
|
|
GHRFunc predicate,
|
|
gpointer user_data)
|
|
{
|
|
gsize i;
|
|
#ifndef G_DISABLE_ASSERT
|
|
gint version;
|
|
#endif
|
|
gboolean match;
|
|
|
|
g_return_val_if_fail (hash_table != NULL, NULL);
|
|
g_return_val_if_fail (predicate != NULL, NULL);
|
|
|
|
#ifndef G_DISABLE_ASSERT
|
|
version = hash_table->version;
|
|
#endif
|
|
|
|
match = FALSE;
|
|
|
|
for (i = 0; i < hash_table->size; i++)
|
|
{
|
|
guint node_hash = hash_table->hashes[i];
|
|
gpointer node_key = g_hash_table_fetch_key_or_value (hash_table->keys, i, hash_table->have_big_keys);
|
|
gpointer node_value = g_hash_table_fetch_key_or_value (hash_table->values, i, hash_table->have_big_values);
|
|
|
|
if (HASH_IS_REAL (node_hash))
|
|
match = predicate (node_key, node_value, user_data);
|
|
|
|
#ifndef G_DISABLE_ASSERT
|
|
g_return_val_if_fail (version == hash_table->version, NULL);
|
|
#endif
|
|
|
|
if (match)
|
|
return node_value;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/**
|
|
* g_hash_table_size:
|
|
* @hash_table: a #GHashTable
|
|
*
|
|
* Returns the number of elements contained in the #GHashTable.
|
|
*
|
|
* Returns: the number of key/value pairs in the #GHashTable.
|
|
*/
|
|
guint
|
|
g_hash_table_size (GHashTable *hash_table)
|
|
{
|
|
g_return_val_if_fail (hash_table != NULL, 0);
|
|
|
|
return hash_table->nnodes;
|
|
}
|
|
|
|
/**
|
|
* g_hash_table_get_keys:
|
|
* @hash_table: a #GHashTable
|
|
*
|
|
* Retrieves every key inside @hash_table. The returned data is valid
|
|
* until changes to the hash release those keys.
|
|
*
|
|
* This iterates over every entry in the hash table to build its return value.
|
|
* To iterate over the entries in a #GHashTable more efficiently, use a
|
|
* #GHashTableIter.
|
|
*
|
|
* Returns: (transfer container): a #GList containing all the keys
|
|
* inside the hash table. The content of the list is owned by the
|
|
* hash table and should not be modified or freed. Use g_list_free()
|
|
* when done using the list.
|
|
*
|
|
* Since: 2.14
|
|
*/
|
|
GList *
|
|
g_hash_table_get_keys (GHashTable *hash_table)
|
|
{
|
|
gsize i;
|
|
GList *retval;
|
|
|
|
g_return_val_if_fail (hash_table != NULL, NULL);
|
|
|
|
retval = NULL;
|
|
for (i = 0; i < hash_table->size; i++)
|
|
{
|
|
if (HASH_IS_REAL (hash_table->hashes[i]))
|
|
retval = g_list_prepend (retval, g_hash_table_fetch_key_or_value (hash_table->keys, i, hash_table->have_big_keys));
|
|
}
|
|
|
|
return retval;
|
|
}
|
|
|
|
/**
|
|
* g_hash_table_get_keys_as_array:
|
|
* @hash_table: a #GHashTable
|
|
* @length: (out): the length of the returned array
|
|
*
|
|
* Retrieves every key inside @hash_table, as an array.
|
|
*
|
|
* The returned array is %NULL-terminated but may contain %NULL as a
|
|
* key. Use @length to determine the true length if it's possible that
|
|
* %NULL was used as the value for a key.
|
|
*
|
|
* Note: in the common case of a string-keyed #GHashTable, the return
|
|
* value of this function can be conveniently cast to (const gchar **).
|
|
*
|
|
* This iterates over every entry in the hash table to build its return value.
|
|
* To iterate over the entries in a #GHashTable more efficiently, use a
|
|
* #GHashTableIter.
|
|
*
|
|
* You should always free the return result with g_free(). In the
|
|
* above-mentioned case of a string-keyed hash table, it may be
|
|
* appropriate to use g_strfreev() if you call g_hash_table_steal_all()
|
|
* first to transfer ownership of the keys.
|
|
*
|
|
* Returns: (array length=length) (transfer container): a
|
|
* %NULL-terminated array containing each key from the table.
|
|
*
|
|
* Since: 2.40
|
|
**/
|
|
gpointer *
|
|
g_hash_table_get_keys_as_array (GHashTable *hash_table,
|
|
guint *length)
|
|
{
|
|
gpointer *result;
|
|
gsize i, j = 0;
|
|
|
|
result = g_new (gpointer, hash_table->nnodes + 1);
|
|
for (i = 0; i < hash_table->size; i++)
|
|
{
|
|
if (HASH_IS_REAL (hash_table->hashes[i]))
|
|
result[j++] = g_hash_table_fetch_key_or_value (hash_table->keys, i, hash_table->have_big_keys);
|
|
}
|
|
g_assert_cmpint (j, ==, hash_table->nnodes);
|
|
result[j] = NULL;
|
|
|
|
if (length)
|
|
*length = j;
|
|
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* g_hash_table_get_values:
|
|
* @hash_table: a #GHashTable
|
|
*
|
|
* Retrieves every value inside @hash_table. The returned data
|
|
* is valid until @hash_table is modified.
|
|
*
|
|
* This iterates over every entry in the hash table to build its return value.
|
|
* To iterate over the entries in a #GHashTable more efficiently, use a
|
|
* #GHashTableIter.
|
|
*
|
|
* Returns: (transfer container): a #GList containing all the values
|
|
* inside the hash table. The content of the list is owned by the
|
|
* hash table and should not be modified or freed. Use g_list_free()
|
|
* when done using the list.
|
|
*
|
|
* Since: 2.14
|
|
*/
|
|
GList *
|
|
g_hash_table_get_values (GHashTable *hash_table)
|
|
{
|
|
gsize i;
|
|
GList *retval;
|
|
|
|
g_return_val_if_fail (hash_table != NULL, NULL);
|
|
|
|
retval = NULL;
|
|
for (i = 0; i < hash_table->size; i++)
|
|
{
|
|
if (HASH_IS_REAL (hash_table->hashes[i]))
|
|
retval = g_list_prepend (retval, g_hash_table_fetch_key_or_value (hash_table->values, i, hash_table->have_big_values));
|
|
}
|
|
|
|
return retval;
|
|
}
|
|
|
|
/* Hash functions.
|
|
*/
|
|
|
|
/**
|
|
* g_str_equal:
|
|
* @v1: (not nullable): a key
|
|
* @v2: (not nullable): a key to compare with @v1
|
|
*
|
|
* Compares two strings for byte-by-byte equality and returns %TRUE
|
|
* if they are equal. It can be passed to g_hash_table_new() as the
|
|
* @key_equal_func parameter, when using non-%NULL strings as keys in a
|
|
* #GHashTable.
|
|
*
|
|
* This function is typically used for hash table comparisons, but can be used
|
|
* for general purpose comparisons of non-%NULL strings. For a %NULL-safe string
|
|
* comparison function, see g_strcmp0().
|
|
*
|
|
* Returns: %TRUE if the two keys match
|
|
*/
|
|
gboolean
|
|
g_str_equal (gconstpointer v1,
|
|
gconstpointer v2)
|
|
{
|
|
const gchar *string1 = v1;
|
|
const gchar *string2 = v2;
|
|
|
|
return strcmp (string1, string2) == 0;
|
|
}
|
|
|
|
/**
|
|
* g_str_hash:
|
|
* @v: (not nullable): a string key
|
|
*
|
|
* Converts a string to a hash value.
|
|
*
|
|
* This function implements the widely used "djb" hash apparently
|
|
* posted by Daniel Bernstein to comp.lang.c some time ago. The 32
|
|
* bit unsigned hash value starts at 5381 and for each byte 'c' in
|
|
* the string, is updated: `hash = hash * 33 + c`. This function
|
|
* uses the signed value of each byte.
|
|
*
|
|
* It can be passed to g_hash_table_new() as the @hash_func parameter,
|
|
* when using non-%NULL strings as keys in a #GHashTable.
|
|
*
|
|
* Note that this function may not be a perfect fit for all use cases.
|
|
* For example, it produces some hash collisions with strings as short
|
|
* as 2.
|
|
*
|
|
* Returns: a hash value corresponding to the key
|
|
*/
|
|
guint
|
|
g_str_hash (gconstpointer v)
|
|
{
|
|
const signed char *p;
|
|
guint32 h = 5381;
|
|
|
|
for (p = v; *p != '\0'; p++)
|
|
h = (h << 5) + h + *p;
|
|
|
|
return h;
|
|
}
|
|
|
|
/**
|
|
* g_direct_hash:
|
|
* @v: (nullable): a #gpointer key
|
|
*
|
|
* Converts a gpointer to a hash value.
|
|
* It can be passed to g_hash_table_new() as the @hash_func parameter,
|
|
* when using opaque pointers compared by pointer value as keys in a
|
|
* #GHashTable.
|
|
*
|
|
* This hash function is also appropriate for keys that are integers
|
|
* stored in pointers, such as `GINT_TO_POINTER (n)`.
|
|
*
|
|
* Returns: a hash value corresponding to the key.
|
|
*/
|
|
guint
|
|
g_direct_hash (gconstpointer v)
|
|
{
|
|
return GPOINTER_TO_UINT (v);
|
|
}
|
|
|
|
/**
|
|
* g_direct_equal:
|
|
* @v1: (nullable): a key
|
|
* @v2: (nullable): a key to compare with @v1
|
|
*
|
|
* Compares two #gpointer arguments and returns %TRUE if they are equal.
|
|
* It can be passed to g_hash_table_new() as the @key_equal_func
|
|
* parameter, when using opaque pointers compared by pointer value as
|
|
* keys in a #GHashTable.
|
|
*
|
|
* This equality function is also appropriate for keys that are integers
|
|
* stored in pointers, such as `GINT_TO_POINTER (n)`.
|
|
*
|
|
* Returns: %TRUE if the two keys match.
|
|
*/
|
|
gboolean
|
|
g_direct_equal (gconstpointer v1,
|
|
gconstpointer v2)
|
|
{
|
|
return v1 == v2;
|
|
}
|
|
|
|
/**
|
|
* g_int_equal:
|
|
* @v1: (not nullable): a pointer to a #gint key
|
|
* @v2: (not nullable): a pointer to a #gint key to compare with @v1
|
|
*
|
|
* Compares the two #gint values being pointed to and returns
|
|
* %TRUE if they are equal.
|
|
* It can be passed to g_hash_table_new() as the @key_equal_func
|
|
* parameter, when using non-%NULL pointers to integers as keys in a
|
|
* #GHashTable.
|
|
*
|
|
* Note that this function acts on pointers to #gint, not on #gint
|
|
* directly: if your hash table's keys are of the form
|
|
* `GINT_TO_POINTER (n)`, use g_direct_equal() instead.
|
|
*
|
|
* Returns: %TRUE if the two keys match.
|
|
*/
|
|
gboolean
|
|
g_int_equal (gconstpointer v1,
|
|
gconstpointer v2)
|
|
{
|
|
return *((const gint*) v1) == *((const gint*) v2);
|
|
}
|
|
|
|
/**
|
|
* g_int_hash:
|
|
* @v: (not nullable): a pointer to a #gint key
|
|
*
|
|
* Converts a pointer to a #gint to a hash value.
|
|
* It can be passed to g_hash_table_new() as the @hash_func parameter,
|
|
* when using non-%NULL pointers to integer values as keys in a #GHashTable.
|
|
*
|
|
* Note that this function acts on pointers to #gint, not on #gint
|
|
* directly: if your hash table's keys are of the form
|
|
* `GINT_TO_POINTER (n)`, use g_direct_hash() instead.
|
|
*
|
|
* Returns: a hash value corresponding to the key.
|
|
*/
|
|
guint
|
|
g_int_hash (gconstpointer v)
|
|
{
|
|
return *(const gint*) v;
|
|
}
|
|
|
|
/**
|
|
* g_int64_equal:
|
|
* @v1: (not nullable): a pointer to a #gint64 key
|
|
* @v2: (not nullable): a pointer to a #gint64 key to compare with @v1
|
|
*
|
|
* Compares the two #gint64 values being pointed to and returns
|
|
* %TRUE if they are equal.
|
|
* It can be passed to g_hash_table_new() as the @key_equal_func
|
|
* parameter, when using non-%NULL pointers to 64-bit integers as keys in a
|
|
* #GHashTable.
|
|
*
|
|
* Returns: %TRUE if the two keys match.
|
|
*
|
|
* Since: 2.22
|
|
*/
|
|
gboolean
|
|
g_int64_equal (gconstpointer v1,
|
|
gconstpointer v2)
|
|
{
|
|
return *((const gint64*) v1) == *((const gint64*) v2);
|
|
}
|
|
|
|
/**
|
|
* g_int64_hash:
|
|
* @v: (not nullable): a pointer to a #gint64 key
|
|
*
|
|
* Converts a pointer to a #gint64 to a hash value.
|
|
*
|
|
* It can be passed to g_hash_table_new() as the @hash_func parameter,
|
|
* when using non-%NULL pointers to 64-bit integer values as keys in a
|
|
* #GHashTable.
|
|
*
|
|
* Returns: a hash value corresponding to the key.
|
|
*
|
|
* Since: 2.22
|
|
*/
|
|
guint
|
|
g_int64_hash (gconstpointer v)
|
|
{
|
|
return (guint) *(const gint64*) v;
|
|
}
|
|
|
|
/**
|
|
* g_double_equal:
|
|
* @v1: (not nullable): a pointer to a #gdouble key
|
|
* @v2: (not nullable): a pointer to a #gdouble key to compare with @v1
|
|
*
|
|
* Compares the two #gdouble values being pointed to and returns
|
|
* %TRUE if they are equal.
|
|
* It can be passed to g_hash_table_new() as the @key_equal_func
|
|
* parameter, when using non-%NULL pointers to doubles as keys in a
|
|
* #GHashTable.
|
|
*
|
|
* Returns: %TRUE if the two keys match.
|
|
*
|
|
* Since: 2.22
|
|
*/
|
|
gboolean
|
|
g_double_equal (gconstpointer v1,
|
|
gconstpointer v2)
|
|
{
|
|
return *((const gdouble*) v1) == *((const gdouble*) v2);
|
|
}
|
|
|
|
/**
|
|
* g_double_hash:
|
|
* @v: (not nullable): a pointer to a #gdouble key
|
|
*
|
|
* Converts a pointer to a #gdouble to a hash value.
|
|
* It can be passed to g_hash_table_new() as the @hash_func parameter,
|
|
* It can be passed to g_hash_table_new() as the @hash_func parameter,
|
|
* when using non-%NULL pointers to doubles as keys in a #GHashTable.
|
|
*
|
|
* Returns: a hash value corresponding to the key.
|
|
*
|
|
* Since: 2.22
|
|
*/
|
|
guint
|
|
g_double_hash (gconstpointer v)
|
|
{
|
|
return (guint) *(const gdouble*) v;
|
|
}
|