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/*

 * Copyright © 2010 Intel Corporation

 *

 * Permission is hereby granted, free of charge, to any person obtaining a

 * copy of this software and associated documentation files (the "Software"),

 * to deal in the Software without restriction, including without limitation

 * the rights to use, copy, modify, merge, publish, distribute, sublicense,

 * and/or sell copies of the Software, and to permit persons to whom the

 * Software is furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice (including the next

 * paragraph) shall be included in all copies or substantial portions of the

 * Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL

 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING

 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER

 * DEALINGS IN THE SOFTWARE.

 */

/**

 * \file ralloc.h

 *

 * ralloc: a recursive memory allocator

 *

 * The ralloc memory allocator creates a hierarchy of allocated

 * objects. Every allocation is in reference to some parent, and

 * every allocated object can in turn be used as the parent of a

 * subsequent allocation. This allows for extremely convenient

 * discarding of an entire tree/sub-tree of allocations by calling

 * ralloc_free on any particular object to free it and all of its

 * children.

 *

 * The conceptual working of ralloc was directly inspired by Andrew

 * Tridgell's talloc, but ralloc is an independent implementation

 * released under the MIT license and tuned for Mesa.

 *

 * talloc is more sophisticated than ralloc in that it includes reference

 * counting and useful debugging features.  However, it is released under

 * a non-permissive open source license.

 */

#ifndef RALLOC_H

#define RALLOC_H

#include 

#include 

#include 

#include "macros.h"

#ifdef __cplusplus

extern "C" {

#endif

/**

 * \def ralloc(ctx, type)

 * Allocate a new object chained off of the given context.

 *

 * This is equivalent to:

 * \code

 * ((type *) ralloc_size(ctx, sizeof(type))

 * \endcode

 */

#define ralloc(ctx, type)  ((type *) ralloc_size(ctx, sizeof(type)))

/**

 * \def rzalloc(ctx, type)

 * Allocate a new object out of the given context and initialize it to zero.

 *

 * This is equivalent to:

 * \code

 * ((type *) rzalloc_size(ctx, sizeof(type))

 * \endcode

 */

#define rzalloc(ctx, type) ((type *) rzalloc_size(ctx, sizeof(type)))

/**

 * Allocate a new ralloc context.

 *

 * While any ralloc'd pointer can be used as a context, sometimes it is useful

 * to simply allocate a context with no associated memory.

 *

 * It is equivalent to:

 * \code

 * ((type *) ralloc_size(ctx, 0)

 * \endcode

 */

void *ralloc_context(const void *ctx);

/**

 * Allocate memory chained off of the given context.

 *

 * This is the core allocation routine which is used by all others.  It

 * simply allocates storage for \p size bytes and returns the pointer,

 * similar to \c malloc.

 */

void *ralloc_size(const void *ctx, size_t size) MALLOCLIKE;

/**

 * Allocate zero-initialized memory chained off of the given context.

 *

 * This is similar to \c calloc with a size of 1.

 */

void *rzalloc_size(const void *ctx, size_t size) MALLOCLIKE;

/**

 * Resize a piece of ralloc-managed memory, preserving data.

 *

 * Similar to \c realloc.  Unlike C89, passing 0 for \p size does not free the

 * memory.  Instead, it resizes it to a 0-byte ralloc context, just like

 * calling ralloc_size(ctx, 0).  This is different from talloc.

 *

 * \param ctx  The context to use for new allocation.  If \p ptr != NULL,

 *             it must be the same as ralloc_parent(\p ptr).

 * \param ptr  Pointer to the memory to be resized.  May be NULL.

 * \param size The amount of memory to allocate, in bytes.

 */

void *reralloc_size(const void *ctx, void *ptr, size_t size);

/// \defgroup array Array Allocators @{

/**

 * \def ralloc_array(ctx, type, count)

 * Allocate an array of objects chained off the given context.

 *

 * Similar to \c calloc, but does not initialize the memory to zero.

 *

 * More than a convenience function, this also checks for integer overflow when

 * multiplying \c sizeof(type) and \p count.  This is necessary for security.

 *

 * This is equivalent to:

 * \code

 * ((type *) ralloc_array_size(ctx, sizeof(type), count)

 * \endcode

 */

#define ralloc_array(ctx, type, count) \

   ((type *) ralloc_array_size(ctx, sizeof(type), count))

/**

 * \def rzalloc_array(ctx, type, count)

 * Allocate a zero-initialized array chained off the given context.

 *

 * Similar to \c calloc.

 *

 * More than a convenience function, this also checks for integer overflow when

 * multiplying \c sizeof(type) and \p count.  This is necessary for security.

 *

 * This is equivalent to:

 * \code

 * ((type *) rzalloc_array_size(ctx, sizeof(type), count)

 * \endcode

 */

#define rzalloc_array(ctx, type, count) \

   ((type *) rzalloc_array_size(ctx, sizeof(type), count))

/**

 * \def reralloc(ctx, ptr, type, count)

 * Resize a ralloc-managed array, preserving data.

 *

 * Similar to \c realloc.  Unlike C89, passing 0 for \p size does not free the

 * memory.  Instead, it resizes it to a 0-byte ralloc context, just like

 * calling ralloc_size(ctx, 0).  This is different from talloc.

 *

 * More than a convenience function, this also checks for integer overflow when

 * multiplying \c sizeof(type) and \p count.  This is necessary for security.

 *

 * \param ctx   The context to use for new allocation.  If \p ptr != NULL,

 *              it must be the same as ralloc_parent(\p ptr).

 * \param ptr   Pointer to the array to be resized.  May be NULL.

 * \param type  The element type.

 * \param count The number of elements to allocate.

 */

#define reralloc(ctx, ptr, type, count) \

   ((type *) reralloc_array_size(ctx, ptr, sizeof(type), count))

/**

 * Allocate memory for an array chained off the given context.

 *

 * Similar to \c calloc, but does not initialize the memory to zero.

 *

 * More than a convenience function, this also checks for integer overflow when

 * multiplying \p size and \p count.  This is necessary for security.

 */

void *ralloc_array_size(const void *ctx, size_t size, unsigned count) MALLOCLIKE;

/**

 * Allocate a zero-initialized array chained off the given context.

 *

 * Similar to \c calloc.

 *

 * More than a convenience function, this also checks for integer overflow when

 * multiplying \p size and \p count.  This is necessary for security.

 */

void *rzalloc_array_size(const void *ctx, size_t size, unsigned count) MALLOCLIKE;

/**

 * Resize a ralloc-managed array, preserving data.

 *

 * Similar to \c realloc.  Unlike C89, passing 0 for \p size does not free the

 * memory.  Instead, it resizes it to a 0-byte ralloc context, just like

 * calling ralloc_size(ctx, 0).  This is different from talloc.

 *

 * More than a convenience function, this also checks for integer overflow when

 * multiplying \c sizeof(type) and \p count.  This is necessary for security.

 *

 * \param ctx   The context to use for new allocation.  If \p ptr != NULL,

 *              it must be the same as ralloc_parent(\p ptr).

 * \param ptr   Pointer to the array to be resized.  May be NULL.

 * \param size  The size of an individual element.

 * \param count The number of elements to allocate.

 *

 * \return True unless allocation failed.

 */

void *reralloc_array_size(const void *ctx, void *ptr, size_t size,

			  unsigned count);

/// @}

/**

 * Free a piece of ralloc-managed memory.

 *

 * This will also free the memory of any children allocated this context.

 */

void ralloc_free(void *ptr);

/**

 * "Steal" memory from one context, changing it to another.

 *

 * This changes \p ptr's context to \p new_ctx.  This is quite useful if

 * memory is allocated out of a temporary context.

 */

void ralloc_steal(const void *new_ctx, void *ptr);

/**

 * Reparent all children from one context to another.

 *

 * This effectively calls ralloc_steal(new_ctx, child) for all children of \p old_ctx.

 */

void ralloc_adopt(const void *new_ctx, void *old_ctx);

/**

 * Return the given pointer's ralloc context.

 */

void *ralloc_parent(const void *ptr);

/**

 * Return a context whose memory will be automatically freed at program exit.

 *

 * The first call to this function creates a context and registers a handler

 * to free it using \c atexit.  This may cause trouble if used in a library

 * loaded with \c dlopen.

 */

void *ralloc_autofree_context(void);

/**

 * Set a callback to occur just before an object is freed.

 */

void ralloc_set_destructor(const void *ptr, void(*destructor)(void *));

/// \defgroup array String Functions @{

/**

 * Duplicate a string, allocating the memory from the given context.

 */

char *ralloc_strdup(const void *ctx, const char *str) MALLOCLIKE;

/**

 * Duplicate a string, allocating the memory from the given context.

 *

 * Like \c strndup, at most \p n characters are copied.  If \p str is longer

 * than \p n characters, \p n are copied, and a termining \c '\0' byte is added.

 */

char *ralloc_strndup(const void *ctx, const char *str, size_t n) MALLOCLIKE;

/**

 * Concatenate two strings, allocating the necessary space.

 *

 * This appends \p str to \p *dest, similar to \c strcat, using ralloc_resize

 * to expand \p *dest to the appropriate size.  \p dest will be updated to the

 * new pointer unless allocation fails.

 *

 * The result will always be null-terminated.

 *

 * \return True unless allocation failed.

 */

bool ralloc_strcat(char **dest, const char *str);

/**

 * Concatenate two strings, allocating the necessary space.

 *

 * This appends at most \p n bytes of \p str to \p *dest, using ralloc_resize

 * to expand \p *dest to the appropriate size.  \p dest will be updated to the

 * new pointer unless allocation fails.

 *

 * The result will always be null-terminated; \p str does not need to be null

 * terminated if it is longer than \p n.

 *

 * \return True unless allocation failed.

 */

bool ralloc_strncat(char **dest, const char *str, size_t n);

/**

 * Print to a string.

 *

 * This is analogous to \c sprintf, but allocates enough space (using \p ctx

 * as the context) for the resulting string.

 *

 * \return The newly allocated string.

 */

char *ralloc_asprintf (const void *ctx, const char *fmt, ...) PRINTFLIKE(2, 3) MALLOCLIKE;

/**

 * Print to a string, given a va_list.

 *

 * This is analogous to \c vsprintf, but allocates enough space (using \p ctx

 * as the context) for the resulting string.

 *

 * \return The newly allocated string.

 */

char *ralloc_vasprintf(const void *ctx, const char *fmt, va_list args) MALLOCLIKE;

/**

 * Rewrite the tail of an existing string, starting at a given index.

 *

 * Overwrites the contents of *str starting at \p start with newly formatted

 * text, including a new null-terminator.  Allocates more memory as necessary.

 *

 * This can be used to append formatted text when the length of the existing

 * string is already known, saving a strlen() call.

 *

 * \sa ralloc_asprintf_append

 *

 * \param str   The string to be updated.

 * \param start The index to start appending new data at.

 * \param fmt   A printf-style formatting string

 *

 * \p str will be updated to the new pointer unless allocation fails.

 * \p start will be increased by the length of the newly formatted text.

 *

 * \return True unless allocation failed.

 */

bool ralloc_asprintf_rewrite_tail(char **str, size_t *start,

				  const char *fmt, ...)

				  PRINTFLIKE(3, 4);

/**

 * Rewrite the tail of an existing string, starting at a given index.

 *

 * Overwrites the contents of *str starting at \p start with newly formatted

 * text, including a new null-terminator.  Allocates more memory as necessary.

 *

 * This can be used to append formatted text when the length of the existing

 * string is already known, saving a strlen() call.

 *

 * \sa ralloc_vasprintf_append

 *

 * \param str   The string to be updated.

 * \param start The index to start appending new data at.

 * \param fmt   A printf-style formatting string

 * \param args  A va_list containing the data to be formatted

 *

 * \p str will be updated to the new pointer unless allocation fails.

 * \p start will be increased by the length of the newly formatted text.

 *

 * \return True unless allocation failed.

 */

bool ralloc_vasprintf_rewrite_tail(char **str, size_t *start, const char *fmt,

				   va_list args);

/**

 * Append formatted text to the supplied string.

 *

 * This is equivalent to

 * \code

 * ralloc_asprintf_rewrite_tail(str, strlen(*str), fmt, ...)

 * \endcode

 *

 * \sa ralloc_asprintf

 * \sa ralloc_asprintf_rewrite_tail

 * \sa ralloc_strcat

 *

 * \p str will be updated to the new pointer unless allocation fails.

 *

 * \return True unless allocation failed.

 */

bool ralloc_asprintf_append (char **str, const char *fmt, ...)

			     PRINTFLIKE(2, 3);

/**

 * Append formatted text to the supplied string, given a va_list.

 *

 * This is equivalent to

 * \code

 * ralloc_vasprintf_rewrite_tail(str, strlen(*str), fmt, args)

 * \endcode

 *

 * \sa ralloc_vasprintf

 * \sa ralloc_vasprintf_rewrite_tail

 * \sa ralloc_strcat

 *

 * \p str will be updated to the new pointer unless allocation fails.

 *

 * \return True unless allocation failed.

 */

bool ralloc_vasprintf_append(char **str, const char *fmt, va_list args);

/// @}

#ifdef __cplusplus

} /* end of extern "C" */

#endif

/**

 * Declare C++ new and delete operators which use ralloc.

 *

 * Placing this macro in the body of a class makes it possible to do:

 *

 * TYPE *var = new(mem_ctx) TYPE(...);

 * delete var;

 *

 * which is more idiomatic in C++ than calling ralloc.

 */

#define DECLARE_RALLOC_CXX_OPERATORS(TYPE)                               \

private:                                                                 \

   static void _ralloc_destructor(void *p)                               \

   {                                                                     \

      reinterpret_cast(p)->~TYPE();                              \

   }                                                                     \

public:                                                                  \

   static void* operator new(size_t size, void *mem_ctx)                 \

   {                                                                     \

      void *p = ralloc_size(mem_ctx, size);                              \

      assert(p != NULL);                                                 \

      if (!HAS_TRIVIAL_DESTRUCTOR(TYPE))                                 \

         ralloc_set_destructor(p, _ralloc_destructor);                   \

      return p;                                                          \

   }                                                                     \

                                                                         \

   static void operator delete(void *p)                                  \

   {                                                                     \

      /* The object's destructor is guaranteed to have already been      \

       * called by the delete operator at this point -- Make sure it's   \

       * not called again.                                               \

       */                                                                \

      if (!HAS_TRIVIAL_DESTRUCTOR(TYPE))                                 \

         ralloc_set_destructor(p, NULL);                                 \

      ralloc_free(p);                                                    \

   }

#endif