1 #ifndef CYGONCE_MEMALLOC_MEMVAR_HXX
2 #define CYGONCE_MEMALLOC_MEMVAR_HXX
4 //==========================================================================
8 // Memory pool with variable block class declarations
10 //==========================================================================
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43 //==========================================================================
44 //#####DESCRIPTIONBEGIN####
46 // Author(s): dsm, jlarmour
49 // Purpose: Define Memvar class interface
50 // Description: Inline class for constructing a variable block allocator
51 // Usage: #include <cyg/memalloc/memvar.hxx>
54 //####DESCRIPTIONEND####
56 //==========================================================================
60 #include <pkgconf/memalloc.h>
61 #ifdef CYGSEM_MEMALLOC_ALLOCATOR_VARIABLE_THREADAWARE
62 # include <pkgconf/system.h>
64 # include <pkgconf/kernel.h>
68 // when used as an implementation for malloc, we need the following
69 // to let the system know the name of the class
70 #define CYGCLS_MEMALLOC_MALLOC_IMPL Cyg_Mempool_Variable
72 // if the implementation is all that's required, don't output anything else
73 #ifndef __MALLOC_IMPL_WANTED
76 #include <cyg/infra/cyg_type.h> // types
77 #include <cyg/infra/cyg_ass.h> // assertion macros
79 #ifdef CYGFUN_KERNEL_THREADS_TIMER
80 # include <cyg/kernel/ktypes.h> // cyg_tick_count
83 #ifdef CYGSEM_MEMALLOC_ALLOCATOR_VARIABLE_THREADAWARE
84 # include <cyg/memalloc/mempolt2.hxx> // kernel safe mempool template
87 #include <cyg/memalloc/mvarimpl.hxx> // implementation of a variable mem pool
88 #include <cyg/memalloc/common.hxx> // Common memory allocator infra
93 class Cyg_Mempool_Variable
96 #ifdef CYGSEM_MEMALLOC_ALLOCATOR_VARIABLE_THREADAWARE
97 Cyg_Mempolt2<Cyg_Mempool_Variable_Implementation> mypool;
99 Cyg_Mempool_Variable_Implementation mypool;
103 // This API makes concrete a class which implements a thread-safe
104 // kernel-savvy memory pool which manages variable size blocks.
106 // Constructor: gives the base and size of the arena in which memory is
107 // to be carved out, note that management structures are taken from the
109 Cyg_Mempool_Variable( cyg_uint8 * /* base */, cyg_int32 /* size */,
110 cyg_int32 /* alignment */=8);
113 ~Cyg_Mempool_Variable();
115 // get some memory; wait if none available
116 // if we aren't configured to be thread-aware this is irrelevant
117 #ifdef CYGSEM_MEMALLOC_ALLOCATOR_VARIABLE_THREADAWARE
119 alloc( cyg_int32 /* size */ );
121 # ifdef CYGFUN_KERNEL_THREADS_TIMER
122 // get some memory with a timeout
124 alloc( cyg_int32 /* size */, cyg_tick_count /* delay_timeout */ );
128 // get some memory, return NULL if none available
130 try_alloc( cyg_int32 /* size */ );
132 // resize existing allocation, if oldsize is non-NULL, previous
133 // allocation size is placed into it. If previous size not available,
134 // it is set to 0. NB previous allocation size may have been rounded up.
135 // Occasionally the allocation can be adjusted *backwards* as well as,
136 // or instead of forwards, therefore the address of the resized
137 // allocation is returned, or NULL if no resizing was possible.
138 // Note that this differs from ::realloc() in that no attempt is
139 // made to call malloc() if resizing is not possible - that is left
140 // to higher layers. The data is copied from old to new though.
141 // The effects of alloc_ptr==NULL or newsize==0 are undefined
143 resize_alloc( cyg_uint8 * /* alloc_ptr */, cyg_int32 /* newsize */,
144 cyg_int32 * /* oldsize */ =NULL );
146 // free the memory back to the pool
147 // returns true on success
149 free( cyg_uint8 * /* ptr */, cyg_int32 /* size */ =0 );
151 // Get memory pool status
152 // flags is a bitmask of requested fields to fill in. The flags are
153 // defined in common.hxx
155 get_status( cyg_mempool_status_flag_t /* flags */,
156 Cyg_Mempool_Status & /* status */ );
158 CYGDBG_DEFINE_CHECK_THIS
161 #endif // ifndef __MALLOC_IMPL_WANTED
163 #endif // ifndef CYGONCE_MEMALLOC_MEMVAR_HXX