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/* Licensed to the Apache Software Foundation (ASF) under one or more
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* contributor license agreements. See the NOTICE file distributed with
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* this work for additional information regarding copyright ownership.
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* The ASF licenses this file to You under the Apache License, Version 2.0
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* (the "License"); you may not use this file except in compliance with
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* the License. You may obtain a copy of the License at
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* http://www.apache.org/licenses/LICENSE-2.0
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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* @brief APR memory allocation
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* Resource allocation routines...
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* designed so that we don't have to keep track of EVERYTHING so that
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* it can be explicitly freed later (a fundamentally unsound strategy ---
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* particularly in the presence of die()).
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* Instead, we maintain pools, and allocate items (both memory and I/O
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* handlers) from the pools --- currently there are two, one for per
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* transaction info, and one for config info. When a transaction is over,
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* we can delete everything in the per-transaction apr_pool_t without fear,
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* and without thinking too hard about it either.
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#include "apr_errno.h"
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#include "apr_general.h" /* for APR_STRINGIFY */
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#define APR_WANT_MEMFUNC /**< for no good reason? */
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* @defgroup apr_pools Memory Pool Functions
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/** The fundamental pool type */
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typedef struct apr_pool_t apr_pool_t;
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* Declaration helper macro to construct apr_foo_pool_get()s.
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* This standardized macro is used by opaque (APR) data types to return
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* the apr_pool_t that is associated with the data type.
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* APR_POOL_DECLARE_ACCESSOR() is used in a header file to declare the
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* accessor function. A typical usage and result would be:
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* APR_POOL_DECLARE_ACCESSOR(file);
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* APR_DECLARE(apr_pool_t *) apr_file_pool_get(apr_file_t *ob);
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* @remark Doxygen unwraps this macro (via doxygen.conf) to provide
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* actual help for each specific occurance of apr_foo_pool_get.
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* @remark the linkage is specified for APR. It would be possible to expand
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* the macros to support other linkages.
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#define APR_POOL_DECLARE_ACCESSOR(type) \
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APR_DECLARE(apr_pool_t *) apr_##type##_pool_get \
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(const apr_##type##_t *the##type)
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* Implementation helper macro to provide apr_foo_pool_get()s.
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* In the implementation, the APR_POOL_IMPLEMENT_ACCESSOR() is used to
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* actually define the function. It assumes the field is named "pool".
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#define APR_POOL_IMPLEMENT_ACCESSOR(type) \
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APR_DECLARE(apr_pool_t *) apr_##type##_pool_get \
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(const apr_##type##_t *the##type) \
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{ return the##type->pool; }
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* | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
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* ---------------------------------
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* | | | | | | | | x | General debug code enabled (useful in
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* combination with --with-efence).
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* | | | | | | | x | | Verbose output on stderr (report
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* CREATE, CLEAR, DESTROY).
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* | | | | x | | | | | Verbose output on stderr (report
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* | | | | | | x | | | Lifetime checking. On each use of a
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* pool, check its lifetime. If the pool
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* is out of scope, abort().
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* In combination with the verbose flag
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* above, it will output LIFE in such an
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* event prior to aborting.
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* | | | | | x | | | | Pool owner checking. On each use of a
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* pool, check if the current thread is the
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* pools owner. If not, abort(). In
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* combination with the verbose flag above,
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* it will output OWNER in such an event
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* prior to aborting. Use the debug
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* function apr_pool_owner_set() to switch
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* When no debug level was specified, assume general debug mode.
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* If level 0 was specified, debugging is switched off
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#if defined(APR_POOL_DEBUG)
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/* If APR_POOL_DEBUG is blank, we get 1; if it is a number, we get -1. */
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#if (APR_POOL_DEBUG - APR_POOL_DEBUG -1 == 1)
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#undef APR_POOL_DEBUG
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#define APR_POOL_DEBUG 1
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#define APR_POOL_DEBUG 0
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/** the place in the code where the particular function was called */
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#define APR_POOL__FILE_LINE__ __FILE__ ":" APR_STRINGIFY(__LINE__)
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/** A function that is called when allocation fails. */
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typedef int (*apr_abortfunc_t)(int retcode);
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* APR memory structure manipulators (pools, tables, and arrays).
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* Setup all of the internal structures required to use pools
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* @remark Programs do NOT need to call this directly. APR will call this
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* automatically from apr_initialize.
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APR_DECLARE(apr_status_t) apr_pool_initialize(void);
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* Tear down all of the internal structures required to use pools
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* @remark Programs do NOT need to call this directly. APR will call this
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* automatically from apr_terminate.
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APR_DECLARE(void) apr_pool_terminate(void);
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* Pool creation/destruction
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#include "apr_allocator.h"
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* @param newpool The pool we have just created.
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* @param parent The parent pool. If this is NULL, the new pool is a root
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* pool. If it is non-NULL, the new pool will inherit all
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* of its parent pool's attributes, except the apr_pool_t will
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* @param abort_fn A function to use if the pool cannot allocate more memory.
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* @param allocator The allocator to use with the new pool. If NULL the
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* allocator of the parent pool will be used.
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APR_DECLARE(apr_status_t) apr_pool_create_ex(apr_pool_t **newpool,
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apr_abortfunc_t abort_fn,
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apr_allocator_t *allocator);
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* Debug version of apr_pool_create_ex.
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* @param newpool @see apr_pool_create.
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* @param parent @see apr_pool_create.
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* @param abort_fn @see apr_pool_create.
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* @param allocator @see apr_pool_create.
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* @param file_line Where the function is called from.
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* This is usually APR_POOL__FILE_LINE__.
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* @remark Only available when APR_POOL_DEBUG is defined.
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* Call this directly if you have you apr_pool_create_ex
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* calls in a wrapper function and wish to override
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* the file_line argument to reflect the caller of
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* your wrapper function. If you do not have
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* apr_pool_create_ex in a wrapper, trust the macro
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* and don't call apr_pool_create_ex_debug directly.
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APR_DECLARE(apr_status_t) apr_pool_create_ex_debug(apr_pool_t **newpool,
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apr_abortfunc_t abort_fn,
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apr_allocator_t *allocator,
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const char *file_line);
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#define apr_pool_create_ex(newpool, parent, abort_fn, allocator) \
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apr_pool_create_ex_debug(newpool, parent, abort_fn, allocator, \
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APR_POOL__FILE_LINE__)
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* @param newpool The pool we have just created.
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* @param parent The parent pool. If this is NULL, the new pool is a root
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* pool. If it is non-NULL, the new pool will inherit all
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* of its parent pool's attributes, except the apr_pool_t will
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APR_DECLARE(apr_status_t) apr_pool_create(apr_pool_t **newpool,
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#define apr_pool_create(newpool, parent) \
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apr_pool_create_ex_debug(newpool, parent, NULL, NULL, \
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APR_POOL__FILE_LINE__)
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#define apr_pool_create(newpool, parent) \
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apr_pool_create_ex(newpool, parent, NULL, NULL)
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* Find the pools allocator
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* @param pool The pool to get the allocator from.
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APR_DECLARE(apr_allocator_t *) apr_pool_allocator_get(apr_pool_t *pool);
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* Clear all memory in the pool and run all the cleanups. This also destroys all
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* @param p The pool to clear
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* @remark This does not actually free the memory, it just allows the pool
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* to re-use this memory for the next allocation.
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* @see apr_pool_destroy()
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APR_DECLARE(void) apr_pool_clear(apr_pool_t *p);
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* Debug version of apr_pool_clear.
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* @param p See: apr_pool_clear.
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* @param file_line Where the function is called from.
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* This is usually APR_POOL__FILE_LINE__.
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* @remark Only available when APR_POOL_DEBUG is defined.
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* Call this directly if you have you apr_pool_clear
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* calls in a wrapper function and wish to override
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* the file_line argument to reflect the caller of
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* your wrapper function. If you do not have
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* apr_pool_clear in a wrapper, trust the macro
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* and don't call apr_pool_destroy_clear directly.
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APR_DECLARE(void) apr_pool_clear_debug(apr_pool_t *p,
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const char *file_line);
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#define apr_pool_clear(p) \
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apr_pool_clear_debug(p, APR_POOL__FILE_LINE__)
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* Destroy the pool. This takes similar action as apr_pool_clear() and then
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* frees all the memory.
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* @param p The pool to destroy
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* @remark This will actually free the memory
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APR_DECLARE(void) apr_pool_destroy(apr_pool_t *p);
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* Debug version of apr_pool_destroy.
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* @param p See: apr_pool_destroy.
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* @param file_line Where the function is called from.
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* This is usually APR_POOL__FILE_LINE__.
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* @remark Only available when APR_POOL_DEBUG is defined.
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* Call this directly if you have you apr_pool_destroy
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* calls in a wrapper function and wish to override
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* the file_line argument to reflect the caller of
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* your wrapper function. If you do not have
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* apr_pool_destroy in a wrapper, trust the macro
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* and don't call apr_pool_destroy_debug directly.
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APR_DECLARE(void) apr_pool_destroy_debug(apr_pool_t *p,
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const char *file_line);
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#define apr_pool_destroy(p) \
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apr_pool_destroy_debug(p, APR_POOL__FILE_LINE__)
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* Allocate a block of memory from a pool
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* @param p The pool to allocate from
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* @param size The amount of memory to allocate
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* @return The allocated memory
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APR_DECLARE(void *) apr_palloc(apr_pool_t *p, apr_size_t size);
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* Debug version of apr_palloc
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* @param p See: apr_palloc
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* @param size See: apr_palloc
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* @param file_line Where the function is called from.
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* This is usually APR_POOL__FILE_LINE__.
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* @return See: apr_palloc
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APR_DECLARE(void *) apr_palloc_debug(apr_pool_t *p, apr_size_t size,
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const char *file_line);
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#define apr_palloc(p, size) \
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apr_palloc_debug(p, size, APR_POOL__FILE_LINE__)
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* Allocate a block of memory from a pool and set all of the memory to 0
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* @param p The pool to allocate from
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* @param size The amount of memory to allocate
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* @return The allocated memory
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APR_DECLARE(void *) apr_pcalloc(apr_pool_t *p, apr_size_t size);
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#elif !APR_POOL_DEBUG
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#define apr_pcalloc(p, size) memset(apr_palloc(p, size), 0, size)
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* Debug version of apr_pcalloc
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* @param p See: apr_pcalloc
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* @param size See: apr_pcalloc
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* @param file_line Where the function is called from.
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* This is usually APR_POOL__FILE_LINE__.
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* @return See: apr_pcalloc
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APR_DECLARE(void *) apr_pcalloc_debug(apr_pool_t *p, apr_size_t size,
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const char *file_line);
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#define apr_pcalloc(p, size) \
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apr_pcalloc_debug(p, size, APR_POOL__FILE_LINE__)
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* Set the function to be called when an allocation failure occurs.
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* @remark If the program wants APR to exit on a memory allocation error,
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* then this function can be called to set the callback to use (for
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* performing cleanup and then exiting). If this function is not called,
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* then APR will return an error and expect the calling program to
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* deal with the error accordingly.
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APR_DECLARE(void) apr_pool_abort_set(apr_abortfunc_t abortfunc,
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* Get the abort function associated with the specified pool.
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* @param pool The pool for retrieving the abort function.
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* @return The abort function for the given pool.
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APR_DECLARE(apr_abortfunc_t) apr_pool_abort_get(apr_pool_t *pool);
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* Get the parent pool of the specified pool.
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* @param pool The pool for retrieving the parent pool.
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* @return The parent of the given pool.
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APR_DECLARE(apr_pool_t *) apr_pool_parent_get(apr_pool_t *pool);
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* Determine if pool a is an ancestor of pool b.
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* @param a The pool to search
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* @param b The pool to search for
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* @return True if a is an ancestor of b, NULL is considered an ancestor
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* @remark if compiled with APR_POOL_DEBUG, this function will also
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* return true if A is a pool which has been guaranteed by the caller
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* (using apr_pool_join) to have a lifetime at least as long as some
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* ancestor of pool B.
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APR_DECLARE(int) apr_pool_is_ancestor(apr_pool_t *a, apr_pool_t *b);
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* Tag a pool (give it a name)
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* @param pool The pool to tag
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APR_DECLARE(void) apr_pool_tag(apr_pool_t *pool, const char *tag);
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* User data management
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* Set the data associated with the current pool
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* @param data The user data associated with the pool.
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* @param key The key to use for association
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* @param cleanup The cleanup program to use to cleanup the data (NULL if none)
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* @param pool The current pool
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* @warning The data to be attached to the pool should have a life span
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* at least as long as the pool it is being attached to.
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* Users of APR must take EXTREME care when choosing a key to
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* use for their data. It is possible to accidentally overwrite
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* data by choosing a key that another part of the program is using.
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* Therefore it is advised that steps are taken to ensure that unique
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* keys are used for all of the userdata objects in a particular pool
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* (the same key in two different pools or a pool and one of its
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* subpools is okay) at all times. Careful namespace prefixing of
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* key names is a typical way to help ensure this uniqueness.
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APR_DECLARE(apr_status_t) apr_pool_userdata_set(
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apr_status_t (*cleanup)(void *),
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* Set the data associated with the current pool
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* @param data The user data associated with the pool.
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* @param key The key to use for association
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* @param cleanup The cleanup program to use to cleanup the data (NULL if none)
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* @param pool The current pool
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* @note same as apr_pool_userdata_set(), except that this version doesn't
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* make a copy of the key (this function is useful, for example, when
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* the key is a string literal)
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* @warning This should NOT be used if the key could change addresses by
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* any means between the apr_pool_userdata_setn() call and a
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* subsequent apr_pool_userdata_get() on that key, such as if a
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* static string is used as a userdata key in a DSO and the DSO could
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* be unloaded and reloaded between the _setn() and the _get(). You
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* MUST use apr_pool_userdata_set() in such cases.
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* @warning More generally, the key and the data to be attached to the
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* pool should have a life span at least as long as the pool itself.
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APR_DECLARE(apr_status_t) apr_pool_userdata_setn(
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apr_status_t (*cleanup)(void *),
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* Return the data associated with the current pool.
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* @param data The user data associated with the pool.
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* @param key The key for the data to retrieve
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* @param pool The current pool.
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APR_DECLARE(apr_status_t) apr_pool_userdata_get(void **data, const char *key,
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* @defgroup PoolCleanup Pool Cleanup Functions
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* Cleanups are performed in the reverse order they were registered. That is:
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* Last In, First Out. A cleanup function can safely allocate memory from
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* the pool that is being cleaned up. It can also safely register additional
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* cleanups which will be run LIFO, directly after the current cleanup
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* terminates. Cleanups have to take caution in calling functions that
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* create subpools. Subpools, created during cleanup will NOT automatically
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* be cleaned up. In other words, cleanups are to clean up after themselves.
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* Register a function to be called when a pool is cleared or destroyed
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* @param p The pool register the cleanup with
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* @param data The data to pass to the cleanup function.
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* @param plain_cleanup The function to call when the pool is cleared
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* @param child_cleanup The function to call when a child process is about
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* to exec - this function is called in the child, obviously!
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APR_DECLARE(void) apr_pool_cleanup_register(
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apr_status_t (*plain_cleanup)(void *),
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apr_status_t (*child_cleanup)(void *));
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* Remove a previously registered cleanup function.
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* The cleanup most recently registered with @a p having the same values of
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* @a data and @a cleanup will be removed.
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* @param p The pool to remove the cleanup from
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* @param data The data of the registered cleanup
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* @param cleanup The function to remove from cleanup
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* @remarks For some strange reason only the plain_cleanup is handled by this
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APR_DECLARE(void) apr_pool_cleanup_kill(apr_pool_t *p, const void *data,
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apr_status_t (*cleanup)(void *));
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* Replace the child cleanup function of a previously registered cleanup.
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* The cleanup most recently registered with @a p having the same values of
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* @a data and @a plain_cleanup will have the registered child cleanup
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* function replaced with @a child_cleanup.
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* @param p The pool of the registered cleanup
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* @param data The data of the registered cleanup
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* @param plain_cleanup The plain cleanup function of the registered cleanup
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* @param child_cleanup The function to register as the child cleanup
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APR_DECLARE(void) apr_pool_child_cleanup_set(
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apr_status_t (*plain_cleanup)(void *),
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apr_status_t (*child_cleanup)(void *));
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* Run the specified cleanup function immediately and unregister it.
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* The cleanup most recently registered with @a p having the same values of
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* @a data and @a cleanup will be removed and @a cleanup will be called
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* with @a data as the argument.
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* @param p The pool to remove the cleanup from
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* @param data The data to remove from cleanup
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* @param cleanup The function to remove from cleanup
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APR_DECLARE(apr_status_t) apr_pool_cleanup_run(
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apr_status_t (*cleanup)(void *));
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* An empty cleanup function.
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* Passed to apr_pool_cleanup_register() when no cleanup is required.
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* @param data The data to cleanup, will not be used by this function.
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APR_DECLARE_NONSTD(apr_status_t) apr_pool_cleanup_null(void *data);
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* Run all registered child cleanups, in preparation for an exec()
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* call in a forked child -- close files, etc., but *don't* flush I/O
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* buffers, *don't* wait for subprocesses, and *don't* free any
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APR_DECLARE(void) apr_pool_cleanup_for_exec(void);
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* @defgroup PoolDebug Pool Debugging functions.
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* pools have nested lifetimes -- sub_pools are destroyed when the
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* parent pool is cleared. We allow certain liberties with operations
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* on things such as tables (and on other structures in a more general
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* sense) where we allow the caller to insert values into a table which
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* were not allocated from the table's pool. The table's data will
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* remain valid as long as all the pools from which its values are
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* allocated remain valid.
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* For example, if B is a sub pool of A, and you build a table T in
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* pool B, then it's safe to insert data allocated in A or B into T
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* (because B lives at most as long as A does, and T is destroyed when
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* B is cleared/destroyed). On the other hand, if S is a table in
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* pool A, it is safe to insert data allocated in A into S, but it
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* is *not safe* to insert data allocated from B into S... because
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* B can be cleared/destroyed before A is (which would leave dangling
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* pointers in T's data structures).
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* In general we say that it is safe to insert data into a table T
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* if the data is allocated in any ancestor of T's pool. This is the
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* basis on which the APR_POOL_DEBUG code works -- it tests these ancestor
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* relationships for all data inserted into tables. APR_POOL_DEBUG also
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* provides tools (apr_pool_find, and apr_pool_is_ancestor) for other
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* folks to implement similar restrictions for their own data
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* However, sometimes this ancestor requirement is inconvenient --
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* sometimes it's necessary to create a sub pool where the sub pool is
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* guaranteed to have the same lifetime as the parent pool. This is a
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* guarantee implemented by the *caller*, not by the pool code. That
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* is, the caller guarantees they won't destroy the sub pool
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* individually prior to destroying the parent pool.
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* In this case the caller must call apr_pool_join() to indicate this
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* guarantee to the APR_POOL_DEBUG code.
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* These functions are only implemented when #APR_POOL_DEBUG is set.
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#if APR_POOL_DEBUG || defined(DOXYGEN)
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* Guarantee that a subpool has the same lifetime as the parent.
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* @param p The parent pool
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* @param sub The subpool
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APR_DECLARE(void) apr_pool_join(apr_pool_t *p, apr_pool_t *sub);
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* Find a pool from something allocated in it.
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* @param mem The thing allocated in the pool
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* @return The pool it is allocated in
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APR_DECLARE(apr_pool_t *) apr_pool_find(const void *mem);
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* Report the number of bytes currently in the pool
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* @param p The pool to inspect
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* @param recurse Recurse/include the subpools' sizes
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* @return The number of bytes
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APR_DECLARE(apr_size_t) apr_pool_num_bytes(apr_pool_t *p, int recurse);
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* @param pool The pool to lock
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* @param flag The flag
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APR_DECLARE(void) apr_pool_lock(apr_pool_t *pool, int flag);
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#else /* APR_POOL_DEBUG or DOXYGEN */
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#define apr_pool_join(a,b)
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#define apr_pool_lock(pool, lock)
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#endif /* APR_POOL_DEBUG or DOXYGEN */
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#endif /* !APR_POOLS_H */
added
removed
install-files/bin/apache/apache2.2.6/include/apr_pools.h
