qpb/qpb_allocator.h

   1 /*
   2  * qpb_allocator.h
   3  *
   4  * @copyright Copyright (C) 2016 Sproute Networks, Inc.
   5  *
   6  * @author Avneesh Sachdev <avneesh@sproute.com>
   7  *
   8  * This file is part of Quagga.
   9  *
  10  * Quagga is free software; you can redistribute it and/or modify it
  11  * under the terms of the GNU General Public License as published by the
  12  * Free Software Foundation; either version 2, or (at your option) any
  13  * later version.
  14  *
  15  * Quagga is distributed in the hope that it will be useful, but
  16  * WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  * General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with Quagga; see the file COPYING.  If not, write to the Free
  22  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  23  * 02111-1307, USA.
  24  */
  25
  26 /*
  27  * Header file for Quagga/FRR protobuf memory management code.
  28  */
  29
  30 #ifndef _QPB_ALLOCATOR_H_
  31 #define _QPB_ALLOCATOR_H_
  32
  33 #include <google/protobuf-c/protobuf-c.h>
  34
  35 struct linear_allocator_t_;
  36
  37 /*
  38  * Alias for ProtobufCAllocator that is easier on the fingers.
  39  */
  40 typedef ProtobufCAllocator qpb_allocator_t;
  41
  42 /*
  43  * qpb_alloc
  44  */
  45 static inline void *qpb_alloc(qpb_allocator_t *allocator, size_t size)
  46 {
  47         return allocator->alloc(allocator->allocator_data, size);
  48 }
  49
  50 /*
  51  * qpb_alloc_ptr_array
  52  *
  53  * Allocate space for the specified number of pointers.
  54  */
  55 static inline void *qpb_alloc_ptr_array(qpb_allocator_t *allocator,
  56                                         size_t num_ptrs)
  57 {
  58         return qpb_alloc(allocator, num_ptrs * sizeof(void *));
  59 }
  60
  61 /*
  62  * qpb_free
  63  */
  64 static inline void qpb_free(qpb_allocator_t *allocator, void *ptr)
  65 {
  66         allocator->free(allocator->allocator_data, ptr);
  67 }
  68
  69 /*
  70  * QPB_ALLOC
  71  *
  72  * Convenience macro to reduce the probability of allocating memory of
  73  * incorrect size. It returns enough memory to store the given type,
  74  * and evaluates to an appropriately typed pointer.
  75  */
  76 #define QPB_ALLOC(allocator, type) (type *)qpb_alloc(allocator, sizeof(type))
  77
  78
  79 /*
  80  * Externs.
  81  */
  82 extern void qpb_allocator_init_linear(qpb_allocator_t *,
  83                                       struct linear_allocator_t_ *);
  84
  85 /*
  86  * The following macros are for the common case where a qpb allocator
  87  * is being used alongside a linear allocator that allocates memory
  88  * off of the stack.
  89  */
  90 #define QPB_DECLARE_STACK_ALLOCATOR(allocator, size)                           \
  91         qpb_allocator_t allocator;                                             \
  92         linear_allocator_t lin_##allocator;                                    \
  93         char lin_##allocator##_buf[size]
  94
  95 #define QPB_INIT_STACK_ALLOCATOR(allocator)                                    \
  96         do {                                                                   \
  97                 linear_allocator_init(&(lin_##allocator),                      \
  98                                       lin_##allocator##_buf,                   \
  99                                       sizeof(lin_##allocator##_buf));          \
 100                 qpb_allocator_init_linear(&allocator, &(lin_##allocator));     \
 101         } while (0)
 102
 103 #define QPB_RESET_STACK_ALLOCATOR(allocator)                                   \
 104         do {                                                                   \
 105                 linear_allocator_reset(&(lin_##allocator));                    \
 106         } while (0)
 107
 108 #endif /* _QPB_ALLOCATOR_H_ */