le_mem.h

    1 /**
    2  * @page c_memory Dynamic Memory Allocation API
    3  *
    4  *
    5  * @subpage le_mem.h "API Reference"
    6  *
    7  * <HR>
    8  *
    9  * Dynamic memory allocation (especially deallocation) using the C runtime heap, through
   10  * malloc, free, strdup, calloc, realloc, etc. can result in performance degradation and out-of-memory
   11  * conditions.
   12  *
   13  * This is due to fragmentation of the heap. The degraded performance and exhausted memory result from indirect interactions
   14  * within the heap between unrelated application code. These issues are non-deterministic,
   15  * and can be very difficult to rectify.
   16  *
   17  * Memory Pools offer a powerful solution.  They trade-off a deterministic amount of
   18  * memory for
   19  *  - deterministic behaviour,
   20  *  - O(1) allocation and release performance, and
   21  *  - built-in memory allocation tracking.
   22  *
   23  * And it brings the power of @b destructors to C!
   24  *
   25  * @todo
   26  *     Do we need to add a "resettable heap" option to the memory management tool kit?
   27  *
   28  *
   29  * @section mem_overview Overview
   30  *
   31  * The most basic usage involves:
   32  *  - Creating a pool (usually done once at process start-up)
   33  *  - Allocating objects (memory blocks) from a pool
   34  *  - Releasing objects back to their pool.
   35  *
   36  * Pools generally can't be deleted.  You create them when your process
   37  * starts-up, and use them until your process terminates. It's up to the OS to clean-up the memory
   38  * pools, along with everything else your process is using, when your process terminates.  (Although,
   39  * if you find yourself really needing to delete pools, @ref mem_sub_pools could offer you a solution.)
   40  *
   41  * Pools also support the following advanced features:
   42  *  - reference counting
   43  *  - destructors
   44  *  - statistics
   45  *  - multi-threading
   46  *  - sub-pools (pools that can be deleted).
   47  *
   48  * The following sections describe these, beginning with the most basic usage and working up to more
   49  * advanced topics.
   50  *
   51  *
   52  * @section mem_creating Creating a Pool
   53  *
   54  * Before allocating memory from a pool, the pool must be created using le_mem_CreatePool(), passing
   55  * it the name of the pool and the size of the objects to be allocated from that pool. This returns
   56  * a reference to the new pool, which has zero free objects in it.
   57  *
   58  * To populate your new pool with free objects, you call @c le_mem_ExpandPool().
   59  * This is separated into two functions (rather than having
   60  * one function with three parameters) to make it virtually impossible to accidentally get the parameters
   61  * in the wrong order (which would result in nasty bugs that couldn't be caught by the compiler).
   62  * The ability to expand pools comes in handy (see @ref mem_pool_sizes).
   63  *
   64  * This code sample defines a class "Point" and a pool "PointPool" used to
   65  * allocate memory for objects of that class:
   66  * @code
   67  * #define MAX_POINTS 12  // Maximum number of points that can be handled.
   68  *
   69  * typedef struct
   70  * {
   71  *     int x;  // pixel position along x-axis
   72  *     int y;  // pixel position along y-axis
   73  * }
   74  * Point_t;
   75  *
   76  * le_mem_PoolRef_t PointPool;
   77  *
   78  * int xx_pt_ProcessStart(void)
   79  * {
   80  *     PointPool = le_mem_CreatePool("xx.pt.Points", sizeof(Point_t));
   81  *     le_mem_ExpandPool(PointPool, MAX_POINTS);
   82  *
   83  *     return SUCCESS;
   84  * }
   85  * @endcode
   86  *
   87  * To make things easier for power-users, @c le_mem_ExpandPool() returns the same pool
   88  * reference that it was given. This allows the xx_pt_ProcessStart() function to be re-implemented
   89  * as follows:
   90  * @code
   91  * int xx_pt_ProcessStart(void)
   92  * {
   93  *     PointPool = le_mem_ExpandPool(le_mem_CreatePool(sizeof(Point_t)), MAX_POINTS);
   94  *
   95  *     return SUCCESS;
   96  * }
   97  * @endcode
   98  *
   99  * Although this requires a dozen or so fewer keystrokes of typing and occupies one less line
  100  * of code, it's arguably less readable than the previous example.
  101  *
  102  * For a discussion on how to pick the number of objects to have in your pools, see @ref mem_pool_sizes.
  103  *
  104  * @section mem_allocating Allocating From a Pool
  105  *
  106  * Allocating from a pool has multiple options:
  107  *  - @c le_mem_TryAlloc() - Quietly return NULL if there are no free blocks in the pool.
  108  *  - @c le_mem_AssertAlloc() - Log an error and take down the process if there are no free blocks in
  109  *                         the pool.
  110  *  - @c le_mem_ForceAlloc() - If there are no free blocks in the pool, log a warning and automatically
  111  *                         expand the pool (or log an error and terminate the calling process there's
  112  *                         not enough free memory to expand the pool).
  113  *
  114  * All of these functions take a pool reference and return a pointer to the object
  115  * allocated from the pool.
  116  *
  117  * The first option, using @c le_mem_TryAlloc(), is the
  118  *  closest to the way good old malloc() works.  It requires the caller check the
  119  * return code to see if it's NULL.  This can be annoying enough that a lot of
  120  * people get lazy and don't check the return code (Bad programmer! Bad!). It turns out that
  121  * this option isn't really what people usually want (but occasionally they do)
  122  *
  123  * The second option, using @c le_mem_AssertAlloc(), is only used when the allocation should
  124  * never fail, by design; a failure to allocate a block is a fatal error.
  125  * This isn't often used, but can save a lot of boilerplate error checking code.
  126  *
  127  * The third option, @c using le_mem_ForceAlloc(), is the one that gets used most often.
  128  * It allows developers to avoid writing error checking code, because the allocation will
  129  * essentially never fail because it's handled inside the memory allocator.  It also
  130  * allows developers to defer fine tuning their pool sizes until after they get things working.
  131  * Later, they check the logs for pool size usage, and then modify their pool sizes accordingly.
  132  * If a particular pool is continually growing, it's a good indication there's a
  133  * memory leak. This permits seeing exactly what objects are being leaked.  If certain debug
  134  * options are turned on, they can even find out which line in which file allocated the blocks
  135  *  being leaked.
  136  *
  137  *
  138  * @section mem_releasing Releasing Back Into a Pool
  139  *
  140  * Releasing memory back to a pool never fails, so there's no need to check a return code.
  141  * Also, each object knows which pool it came from, so the code that releases the object doesn't have to care.
  142  * All it has to do is call @c le_mem_Release() and pass a pointer to the object to be released.
  143  *
  144  * The critical thing to remember is that once an object has been released, it
  145  * <b> must never be accessed again </b>.  Here is a <b> very bad code example</b>:
  146  * @code
  147  *     Point_t* pointPtr = le_mem_ForceAlloc(PointPool);
  148  *     pointPtr->x = 5;
  149  *     pointPtr->y = 10;
  150  *     le_mem_Release(pointPtr);
  151  *     printf("Point is at position (%d, %d).\n", pointPtr->x, pointPtr->y);
  152  * @endcode
  153  *
  154  *
  155  * @section mem_ref_counting Reference Counting
  156  *
  157  * Reference counting is a powerful feature of our memory pools.  Here's how it works:
  158  *  - Every object allocated from a pool starts with a reference count of 1.
  159  *  - Whenever someone calls le_mem_AddRef() on an object, its reference count is incremented by 1.
  160  *  - When it's released, its reference count is decremented by 1.
  161  *  - When its reference count reaches zero, it's destroyed (i.e., its memory is released back into the pool.)
  162  *
  163  * This allows one function to:
  164  *  - create an object.
  165  *  - work with it.
  166  *  - increment its reference count and pass a pointer to the object to another function (or thread, data structure, etc.).
  167  *  - work with it some more.
  168  *  - release the object without having to worry about when the other function is finished with it.
  169  *
  170  * The other function also releases the object when it's done with it.  So, the object will
  171  * exist until both functions are done.
  172  *
  173  * If there are multiple threads involved, be careful to protect the shared
  174  * object from race conditions(see the @ref mem_threading).
  175  *
  176  * Another great advantage of reference counting is it enables @ref mem_destructors.
  177  *
  178  * @note le_mem_GetRefCount() can be used to check the current reference count on an object.
  179  *
  180  * @section mem_destructors Destructors
  181  *
  182  * Destructors are a powerful feature of C++.  Anyone who has any non-trivial experience with C++ has
  183  * used them.  Because C was created before object-oriented programming was around, there's
  184  * no native language support for destructors in C.  Object-oriented design is still possible
  185  * and highly desireable even when the programming is done in C.
  186  *
  187  * In Legato, it's possible to call @c le_mem_SetDestructor() to attach a function to a memory pool
  188  * to be used as a destructor for objects allocated from that pool. If a pool has a destructor,
  189  *  whenever the reference count reaches zero for an object allocated from that pool,
  190  * the pool's destructor function will pass a pointer to that object.  After
  191  * the destructor returns, the object will be fully destroyed, and its memory will be released back
  192  * into the pool for later reuse by another object.
  193  *
  194  * Here's a destructor code sample:
  195  * @code
  196  * static void PointDestructor(void* objPtr)
  197  * {
  198  *     Point_t* pointPtr = objPtr;
  199  *
  200  *     printf("Destroying point (%d, %d)\n", pointPtr->x, pointPtr->y);
  201  *
  202  *     @todo Add more to sample.
  203  * }
  204  *
  205  * int xx_pt_ProcessStart(void)
  206  * {
  207  *     PointPool = le_mem_CreatePool(sizeof(Point_t));
  208  *     le_mem_ExpandPool(PointPool, MAX_POINTS);
  209  *     le_mem_SetDestructor(PointPool, PointDestructor);
  210  *     return SUCCESS;
  211  * }
  212  *
  213  * static void DeletePointList(Point_t** pointList, size_t numPoints)
  214  * {
  215  *     size_t i;
  216  *     for (i = 0; i < numPoints; i++)
  217  *     {
  218  *         le_mem_Release(pointList[i]);
  219  *     }
  220  * }
  221  * @endcode
  222  *
  223  * In this sample, when DeletePointList() is called (with a pointer to an array of pointers
  224  * to Point_t objects with reference counts of 1), each of the objects in the pointList is
  225  * released.  This causes their reference counts to hit 0, which triggers executing
  226  * PointDestructor() for each object in the pointList, and the "Destroying point..." message will
  227  * be printed for each.
  228  *
  229  *
  230  * @section mem_stats Statistics
  231  *
  232  * Some statistics are gathered for each memory pool:
  233  *  - Number of allocations.
  234  *  - Number of currently free objects.
  235  *  - Number of overflows (times that le_mem_ForceAlloc() had to expand the pool).
  236  *
  237  * Statistics (and other pool properties) can be checked using functions:
  238  *  - @c le_mem_GetStats()
  239  *  - @c le_mem_GetObjectCount()
  240  *  - @c le_mem_GetObjectSize()
  241  *
  242  * Statistics are fetched together atomically using a single function call.
  243  * This prevents inconsistencies between them if in a multi-threaded program.
  244  *
  245  * If you don't have a reference to a specified pool, but you have the name of the pool, you can
  246  * get a reference to the pool using @c le_mem_FindPool().
  247  *
  248  * In addition to programmatically fetching these, they're also available through the
  249  * "poolstat" console command (unless your process's main thread is blocked).
  250  *
  251  * To reset the pool statistics, use @c le_mem_ResetStats().
  252  *
  253  * @section mem_diagnostics Diagnostics
  254  *
  255  * The memory system also supports two different forms of diagnostics.  Both are enabled by setting
  256  * the appropriate KConfig options when building the framework.
  257  *
  258  * The first of these options is @ref MEM_TRACE.  When you enable @ref MEM_TRACE every pool is given
  259  * a tracepoint with the name of the pool on creation.
  260  *
  261  * For instance, the configTree node pool is called, "configTree.nodePool".  So to enable a trace of
  262  * all config tree node creation and deletion one would use the log tool as follows:
  263  *
  264  * @code
  265  * $ log trace configTree.nodePool
  266  * @endcode
  267  *
  268  * The second diagnostic build flag is @ref MEM_POOLS.  When @ref MEM_POOLS is disabled, the pools
  269  * are disabled and instead malloc and free are directly used.  Thus enabling the use of tools
  270  * like Valgrind.
  271  *
  272  * @section mem_threading Multi-Threading
  273  *
  274  * All functions in this API are <b> thread-safe, but not async-safe </b>.  The objects
  275  * allocated from pools are not inherently protected from races between threads.
  276  *
  277  * Allocating and releasing objects, checking stats, incrementing reference
  278  * counts, etc. can all be done from multiple threads (excluding signal handlers) without having
  279  * to worry about corrupting the memory pools' hidden internal data structures.
  280  *
  281  * There's no magical way to prevent different threads from interferring with each other
  282  * if they both access the @a contents of the same object at the same time.
  283  *
  284  * The best way to prevent multi-threaded race conditions is simply don't share data between
  285  * threads. If multiple threads must access the same data structure, then mutexes, semaphores,
  286  * or similar methods should be used to @a synchronize threads and avoid
  287  * data structure corruption or thread misbehaviour.
  288  *
  289  * Although memory pools are @a thread-safe, they are not @a async-safe. This means that memory pools
  290  * @a can be corrupted if they are accessed by a signal handler while they are being accessed
  291  * by a normal thread.  To be safe, <b> don't call any memory pool functions from within a signal handler. </b>
  292  *
  293  * One problem using destructor functions in a
  294  * multi-threaded environment is that the destructor function modifies a data structure shared
  295  * between threads, so it's easy to forget to synchronize calls to @c le_mem_Release() with other code
  296  *  accessing the data structure.  If a mutex is used to coordinate access to
  297  * the data structure, then the mutex must be held by the thread that calls le_mem_Release() to
  298  * ensure there's no other thread accessing the data structure when the destructor runs.
  299  *
  300  * @section mem_pool_sizes Managing Pool Sizes
  301  *
  302  * We know it's possible to have pools automatically expand
  303  * when they are exhausted, but we don't really want that to happen normally.
  304  * Ideally, the pools should be fully allocated to their maximum sizes at start-up so there aren't
  305  * any surprises later when certain feature combinations cause the
  306  * system to run out of memory in the field.  If we allocate everything we think
  307  * is needed up-front, then we are much more likely to uncover any memory shortages during
  308  * testing, before it's in the field.
  309  *
  310  * Choosing the right size for your pools correctly at start-up is easy to do if there is a maximum
  311  * number of fixed, external @a things that are being represented by the objects being allocated
  312  * from the pool.  If the pool holds "call objects" representing phone calls over a T1
  313  * carrier that will never carry more than 24 calls at a time, then it's obvious that you need to
  314  * size your call object pool at 24.
  315  *
  316  * Other times, it's not so easy to choose the pool size like
  317  * code to be reused in different products or different configurations that have different
  318  * needs.  In those cases, you still have a few options:
  319  *
  320  *  - At start-up, query the operating environment and base the pool sizes.
  321  *  - Read a configuration setting from a file or other configuration data source.
  322  *  - Use a build-time configuration setting.
  323  *
  324  * The build-time configuration setting is the easiest, and generally requires less
  325  * interaction between components at start-up simplifying APIs
  326  * and reducing boot times.
  327  *
  328  * If the pool size must be determined at start-up, use @c le_mem_ExpandPool().
  329  * Perhaps there's a service-provider module designed to allocate objects on behalf
  330  * of client. It can have multiple clients at the same time, but it doesn't know how many clients
  331  * or what their resource needs will be until the clients register with it at start-up.  We'd want
  332  * those clients to be as decoupled from each other as possible (i.e., we want the clients know as little
  333  * as possible about each other); we don't want the clients to get together and add up all
  334  * their needs before telling the service-provider.  We'd rather have the clients independently
  335  * report their own needs to the service-provider.  Also, we don't want each client to have to wait
  336  * for all the other clients to report their needs before starting to use
  337  * the services offered by the service-provider.  That would add more complexity to the interactions
  338  * between the clients and the service-provider.
  339  *
  340  * This is what should happen when the service-provider can't wait for all clients
  341  * to report their needs before creating the pool:
  342  *  - When the service-provider starts up, it creates an empty pool.
  343  *  - Whenever a client registers itself with the service-provider, the client can tell the
  344  *    service-provider what its specific needs are, and the service-provider can expand its
  345  *    object pool accordingly.
  346  *  - Since registrations happen at start-up, pool expansion occurs
  347  *    at start-up, and testing will likely find any pool sizing before going into the field.
  348  *
  349  * Where clients dynamically start and stop during runtime in response
  350  * to external events (e.g., when someone is using the device's Web UI), we still have
  351  * a problem because we can't @a shrink pools or delete pools when clients go away.  This is where
  352  * @ref mem_sub_pools is useful.
  353  *
  354  * @section mem_sub_pools Sub-Pools
  355  *
  356  * Essentially, a Sub-Pool is a memory pool that gets its blocks from another pool (the super-pool).
  357  * Sub Pools @a can be deleted, causing its blocks to be released back into the super-pool.
  358  *
  359  * This is useful when a service-provider module needs to handle clients that
  360  * dynamically pop into existence and later disappear again.  When a client attaches to the service
  361  * and says it will probably need a maximum of X of the service-provider's resources, the
  362  * service provider can set aside that many of those resources in a sub-pool for that client.
  363  * If that client goes over its limit, the sub-pool will log a warning message.
  364  *
  365  * The problem of sizing the super-pool correctly at start-up still exists,
  366  * so what's the point of having a sub-pool, when all of the resources could just be allocated from
  367  * the super-pool?
  368  *
  369  * The benefit is really gained in troubleshooting.  If client A, B, C, D and E are
  370  * all behaving nicely, but client F is leaking resources, the sub-pool created
  371  * on behalf of client F will start warning about the memory leak; time won't have to be
  372  * wasted looking at clients A through E to rule them out.
  373  *
  374  * To create a sub-pool, call @c le_mem_CreateSubPool(). It takes a reference to the super-pool
  375  * and the number of objects to move to the sub-pool, and it returns a reference to the new sub-pool.
  376  *
  377  * To delete a sub-pool, call @c le_mem_DeleteSubPool().  Do not try to use it to delete a pool that
  378  * was created using le_mem_CreatePool().  It's only for sub-pools created using le_mem_CreateSubPool().
  379  * Also, it's @b not okay to delete a sub-pool while there are still blocks allocated from it, or
  380  * if it has any sub-pools.  You'll see errors in your logs if you do that.
  381  *
  382  * Sub-Pools automatically inherit their parent's destructor function.
  383  *
  384  * @section mem_reduced_pools Reduced-size pools
  385  *
  386  * One problem that occurs with memory pools is where objects of different sizes need to be
  387  * stored.  A classic example is strings -- the longest string an application needs to be able
  388  * to handle may be much longer than the typical string size.  In this case a lot of memory
  389  * will be wasted with standard memory pools, since all objects allocated from the pool will
  390  * be the size of the longest possible object.
  391  *
  392  * The solution is to use reduced-size pools.  These are a kind of sub-pool where the size
  393  * of the object in the sub-pool is different from the size of the object in the super-pool.
  394  * This way multiple blocks from the sub-pool can be stored in a single block of the super-pool.
  395  *
  396  * Reduced-size pools have some limitations:
  397  *
  398  *  - Each block in the super-pool is divided up to create blocks in the subpool.  So subpool
  399  *    blocks sizes must be less than half the size of the super-pool block size.  An attempt to
  400  *    create a pool with a larger block size will just return a reference to the super-pool.
  401  *  - Due overhead, each block actually requires 8-80 bytes more space than requested.
  402  *    There is little point in subdividing pools < 4x overhead, or ~300 bytes in the default
  403  *    configuration.  Note the exact amount of overhead depends on the size of the guard bands
  404  *    and the size of pointer on your target.
  405  *  - Blocks used by the reduced pool are permanently moved from the super-pool to the reduced
  406  *    pool.  This must be taken into account when sizing the super-pool.
  407  *
  408  * Example 1:
  409  *
  410  * A network service needs to allocate space for packets received over a network.  It should
  411  * Typical packet length is up to 200 bytes, but occasional packets may be up to 1500 bytes.  The
  412  * service needs to be able to queue at least 32 packets, up to 5 of which can be 1500 bytes.
  413  * Two pools are used: A pool of 12 objects 1500 bytes in size, and a reduced-size pool of 32
  414  * objects 200 bytes in size (280 bytes with overhead).  Seven objects from the superpool are
  415  * used to store reduced-size objects.  This represents a memory savings of 60% compared with
  416  * a pool of 32 1500 byte objects.
  417  *
  418  * Example 2:
  419  *
  420  * An application builds file paths which can be from 16-70 bytes.  Only three such paths can be
  421  * created at a time, but they can be any size.  In this case it is better to just create
  422  * a single pool of three 70-byte objects.  Most of the potential space gains would be consumed
  423  * by overhead.  Even if this was not the case, the super pool still needs three free objects
  424  * in addition to the objects required by the subpool, so there is no space savings.
  425  *
  426  * To create a reduced-size pool, use @c le_mem_CreateReducedPool().  It takes a reference to the
  427  * super-pool, the initial number of objects in the sub-pool, and size of an object in the sub-pool
  428  * compared with the parent pool, and it returns a reference to the new sub-pool.
  429  *
  430  * Reduced-size pools are deleted using @c le_mem_DeleteSubPool() like other sub-pools.
  431  *
  432  * To help the programmer pick the right pool to allocate from, reduced-size pools provide
  433  * @c le_mem_TryVarAlloc(), @c le_mem_AssertVarAlloc() and @c le_mem_ForceVarAlloc() functions.
  434  * In addition to the pool these take the object size to allocate.  If this size is larger than
  435  * the pool's object size and the pool is a reduced-size pool, and there is a parent pool
  436  * large enough for this object, it will allocate the object from the parent pool instead.
  437  * If no parent pool is large enough, the program will exit.
  438  *
  439  * You can call @c le_mem_GetBlockSize() to get the actual size of the object returned by
  440  * one of these functions.
  441  *
  442  * As with other sub-pools, they cannot be deleted while any blocks are allocated from the pool,
  443  * or it has any sub-pools.  Reduced-size pools also automatically inherit their parent's
  444  * destructor function.
  445  *
  446  * <HR>
  447  *
  448  * Copyright (C) Sierra Wireless Inc.
  449  */
  450 
  451 //--------------------------------------------------------------------------------------------------
  452 /** @file le_mem.h
  453  *
  454  * Legato @ref c_memory include file.
  455  *
  456  * Copyright (C) Sierra Wireless Inc.
  457  *
  458  */
  459 //--------------------------------------------------------------------------------------------------
  460 
  461 #ifndef LEGATO_MEM_INCLUDE_GUARD
  462 #define LEGATO_MEM_INCLUDE_GUARD
  463 
  464 #ifndef LE_COMPONENT_NAME
  465 #   define LE_COMPONENT_NAME
  466 #endif
  467 
  468 //--------------------------------------------------------------------------------------------------
  469 /**
  470  * Prototype for destructor functions.
  471  *
  472  * @param objPtr   Pointer to the object where reference count has reached zero.  After the destructor
  473  *                 returns this object's memory will be released back into the pool (and this pointer
  474  *                 will become invalid).
  475  *
  476  * @return Nothing.
  477  *
  478  * See @ref mem_destructors for more information.
  479  */
  480 //--------------------------------------------------------------------------------------------------
  481 typedef void (*le_mem_Destructor_t)
  482 (
  483     void* objPtr    ///< see parameter documentation in comment above.
  484 );
  485 
  486 // Max memory pool name bytes -- must match definition in limit.h
  487 #define LE_MEM_LIMIT_MAX_MEM_POOL_NAME_BYTES 32
  488 
  489 //--------------------------------------------------------------------------------------------------
  490 /**
  491  * Definition of a memory pool.
  492  *
  493  * @note This should not be used directly.  To create a memory pool use either le_mem_CreatePool()
  494  *       or LE_MEM_DEFINE_STATIC_POOL()/le_mem_InitStaticPool().
  495  */
  496 //--------------------------------------------------------------------------------------------------
  497 typedef struct le_mem_Pool
  498 {
  499     le_dls_Link_t poolLink;             ///< This pool's link in the list of memory pools.
  500     struct le_mem_Pool* superPoolPtr;   ///< A pointer to our super pool if we are a sub-pool. NULL
  501                                         ///  if we are not a sub-pool.
  502 #if LE_CONFIG_MEM_POOL_STATS
  503     // These members go before LE_CONFIG_MEM_POOLS so numAllocations will always be aligned, even on
  504     // 32-bit architectures, even when LE_CONFIG_MEM_POOLS is not declared
  505     size_t numOverflows;                ///< Number of times le_mem_ForceAlloc() had to expand pool.
  506     uint64_t numAllocations;            ///< Total number of times an object has been allocated
  507                                         ///  from this pool.
  508     size_t maxNumBlocksUsed;            ///< Maximum number of allocated blocks at any one time.
  509 #endif
  510 #if LE_CONFIG_MEM_POOLS
  511     le_sls_List_t freeList;             ///< List of free memory blocks.
  512 #endif
  513 
  514     size_t userDataSize;                ///< Size of the object requested by the client in bytes.
  515     size_t blockSize;                   ///< Number of bytes in a block, including all overhead.
  516     size_t totalBlocks;                 ///< Total number of blocks in this pool including free
  517                                         ///  and allocated blocks.
  518     size_t numBlocksInUse;              ///< Number of currently allocated blocks.
  519     size_t numBlocksToForce;            ///< Number of blocks that is added when Force Alloc
  520                                         ///  expands the pool.
  521 #if LE_CONFIG_MEM_TRACE
  522     le_log_TraceRef_t memTrace;         ///< If tracing is enabled, keeps track of a trace object
  523                                         ///< for this pool.
  524 #endif
  525 
  526     le_mem_Destructor_t destructor;     ///< The destructor for objects in this pool.
  527 #if LE_CONFIG_MEM_POOL_NAMES_ENABLED
  528     char name[LE_MEM_LIMIT_MAX_MEM_POOL_NAME_BYTES]; ///< Name of the pool.
  529 #endif
  530 }
  531 le_mem_Pool_t;
  532 
  533 
  534 //--------------------------------------------------------------------------------------------------
  535 /**
  536  * Objects of this type are used to refer to a memory pool created using either
  537  * le_mem_CreatePool() or le_mem_CreateSubPool().
  538  */
  539 //--------------------------------------------------------------------------------------------------
  540 typedef struct le_mem_Pool* le_mem_PoolRef_t;
  541 
  542 
  543 //--------------------------------------------------------------------------------------------------
  544 /**
  545  * List of memory pool statistics.
  546  */
  547 //--------------------------------------------------------------------------------------------------
  548 typedef struct
  549 {
  550     size_t      numBlocksInUse;     ///< Number of currently allocated blocks.
  551     size_t      maxNumBlocksUsed;   ///< Maximum number of allocated blocks at any one time.
  552     size_t      numOverflows;       ///< Number of times le_mem_ForceAlloc() had to expand the pool.
  553     uint64_t    numAllocs;          ///< Number of times an object has been allocated from this pool.
  554     size_t      numFree;            ///< Number of free objects currently available in this pool.
  555 }
  556 le_mem_PoolStats_t;
  557 
  558 
  559 #if LE_CONFIG_MEM_TRACE
  560     //----------------------------------------------------------------------------------------------
  561     /**
  562      * Internal function used to retrieve a pool handle for a given pool block.
  563      */
  564     //----------------------------------------------------------------------------------------------
  565     le_mem_PoolRef_t _le_mem_GetBlockPool
  566     (
  567         void*   objPtr  ///< [IN] Pointer to the object we're finding a pool for.
  568     );
  569 
  570     typedef void* (*_le_mem_AllocFunc_t)(le_mem_PoolRef_t pool);
  571 
  572     //----------------------------------------------------------------------------------------------
  573     /**
  574      * Internal function used to call a memory allocation function and trace its call site.
  575      */
  576     //----------------------------------------------------------------------------------------------
  577     void* _le_mem_AllocTracer
  578     (
  579         le_mem_PoolRef_t     pool,             ///< [IN] The pool activity we're tracing.
  580         _le_mem_AllocFunc_t  funcPtr,          ///< [IN] Pointer to the mem function in question.
  581         const char*          poolFunction,     ///< [IN] The pool function being called.
  582         const char*          file,             ///< [IN] The file the call came from.
  583         const char*          callingfunction,  ///< [IN] The function calling into the pool.
  584         size_t               line              ///< [IN] The line in the function where the call
  585                                                ///       occurred.
  586     );
  587 
  588     //----------------------------------------------------------------------------------------------
  589     /**
  590      * Internal function used to call a variable memory allocation function and trace its call site.
  591      */
  592     //----------------------------------------------------------------------------------------------
  593     void* _le_mem_VarAllocTracer
  594     (
  595         le_mem_PoolRef_t     pool,             ///< [IN] The pool activity we're tracing.
  596         size_t               size,             ///< [IN] The size of block to allocate
  597         _le_mem_AllocFunc_t  funcPtr,          ///< [IN] Pointer to the mem function in question.
  598         const char*          poolFunction,     ///< [IN] The pool function being called.
  599         const char*          file,             ///< [IN] The file the call came from.
  600         const char*          callingfunction,  ///< [IN] The function calling into the pool.
  601         size_t               line              ///< [IN] The line in the function where the call
  602                                                ///       occurred.
  603     );
  604 
  605     //----------------------------------------------------------------------------------------------
  606     /**
  607      * Internal function used to trace memory pool activity.
  608      */
  609     //----------------------------------------------------------------------------------------------
  610     void _le_mem_Trace
  611     (
  612         le_mem_PoolRef_t    pool,             ///< [IN] The pool activity we're tracing.
  613         const char*         file,             ///< [IN] The file the call came from.
  614         const char*         callingfunction,  ///< [IN] The function calling into the pool.
  615         size_t              line,             ///< [IN] The line in the function where the call
  616                                               ///       occurred.
  617         const char*         poolFunction,     ///< [IN] The pool function being called.
  618         void*               blockPtr          ///< [IN] Block allocated/freed.
  619     );
  620 #endif
  621 
  622 
  623 /// @cond HIDDEN_IN_USER_DOCS
  624 //--------------------------------------------------------------------------------------------------
  625 /**
  626  * Internal function used to implement le_mem_InitStaticPool() with automatic component scoping
  627  * of pool names.
  628  */
  629 //--------------------------------------------------------------------------------------------------
  630 le_mem_PoolRef_t _le_mem_InitStaticPool
  631 (
  632     const char* componentName,  ///< [IN] Name of the component.
  633     const char* name,           ///< [IN] Name of the pool inside the component.
  634     size_t      numBlocks,      ///< [IN] Number of members in the pool by default
  635     size_t      objSize, ///< [IN] Size of the individual objects to be allocated from this pool
  636                         /// (in bytes), e.g., sizeof(MyObject_t).
  637     le_mem_Pool_t* poolPtr, ///< [IN] Pointer to pre-allocated pool header.
  638     void* poolDataPtr       ///< [IN] Pointer to pre-allocated pool data.
  639 );
  640 /// @endcond
  641 
  642 
  643 #if LE_CONFIG_MEM_POOL_NAMES_ENABLED
  644 //--------------------------------------------------------------------------------------------------
  645 /** @cond HIDDEN_IN_USER_DOCS
  646  *
  647  * Internal function used to implement le_mem_CreatePool() with automatic component scoping
  648  * of pool names.
  649  */
  650 //--------------------------------------------------------------------------------------------------
  651 le_mem_PoolRef_t _le_mem_CreatePool
  652 (
  653     const char* componentName,  ///< [IN] Name of the component.
  654     const char* name,           ///< [IN] Name of the pool inside the component.
  655     size_t      objSize         ///< [IN] Size of the individual objects to be allocated from this pool
  656                                 /// (in bytes), e.g., sizeof(MyObject_t).
  657 );
  658 /// @endcond
  659 //--------------------------------------------------------------------------------------------------
  660 /**
  661  * Creates an empty memory pool.
  662  *
  663  * @return
  664  *      Reference to the memory pool object.
  665  *
  666  * @note
  667  *      On failure, the process exits, so you don't have to worry about checking the returned
  668  *      reference for validity.
  669  */
  670 //--------------------------------------------------------------------------------------------------
  671 static inline le_mem_PoolRef_t le_mem_CreatePool
  672 (
  673     const char* name,           ///< [IN] Name of the pool inside the component.
  674     size_t      objSize         ///< [IN] Size of the individual objects to be allocated from this pool
  675                                 /// (in bytes), e.g., sizeof(MyObject_t).
  676 )
  677 {
  678     return _le_mem_CreatePool(STRINGIZE(LE_COMPONENT_NAME), name, objSize);
  679 }
  680 #else /* if not LE_CONFIG_MEM_POOL_NAMES_ENABLED */
  681 //--------------------------------------------------------------------------------------------------
  682 /** @cond HIDDEN_IN_USER_DOCS
  683  *
  684  * Internal function used to implement le_mem_CreatePool() with automatic component scoping
  685  * of pool names.
  686  */
  687 //--------------------------------------------------------------------------------------------------
  688 le_mem_PoolRef_t _le_mem_CreatePool
  689 (
  690     size_t      objSize         ///< [IN] Size of the individual objects to be allocated from this pool
  691                                 /// (in bytes), e.g., sizeof(MyObject_t).
  692 );
  693 /// @endcond
  694 //--------------------------------------------------------------------------------------------------
  695 /**
  696  * Creates an empty memory pool.
  697  *
  698  * @return
  699  *      Reference to the memory pool object.
  700  *
  701  * @note
  702  *      On failure, the process exits, so you don't have to worry about checking the returned
  703  *      reference for validity.
  704  */
  705 //--------------------------------------------------------------------------------------------------
  706 LE_DECLARE_INLINE le_mem_PoolRef_t le_mem_CreatePool
  707 (
  708     const char* name,           ///< [IN] Name of the pool inside the component.
  709     size_t      objSize         ///< [IN] Size of the individual objects to be allocated from this pool
  710                                 /// (in bytes), e.g., sizeof(MyObject_t).
  711 )
  712 {
  713     return _le_mem_CreatePool(objSize);
  714 }
  715 #endif /* end LE_CONFIG_MEM_POOL_NAMES_ENABLED */
  716 
  717 //--------------------------------------------------------------------------------------------------
  718 /**
  719  * Number of words in a memory pool, given number of blocks and object size.
  720  *
  721  * @note Only used internally
  722  */
  723 //--------------------------------------------------------------------------------------------------
  724 #define LE_MEM_POOL_WORDS(numBlocks, objSize)                           \
  725     ((numBlocks)*(((sizeof(le_mem_Pool_t*) + sizeof(size_t)) /* sizeof(MemBlock_t) */ + \
  726                    (((objSize)<sizeof(le_sls_Link_t))?sizeof(le_sls_Link_t):(objSize))+ \
  727                    sizeof(uint32_t)*LE_CONFIG_NUM_GUARD_BAND_WORDS*2+      \
  728                    sizeof(size_t) - 1) / sizeof(size_t)))
  729 
  730 //--------------------------------------------------------------------------------------------------
  731 /**
  732  * Declare variables for a static memory pool.
  733  *
  734  * In a static memory pool initial pool memory is statically allocated at compile time, ensuring
  735  * pool can be created with at least some elements.  This is especially valuable on embedded
  736  * systems.
  737  */
  738 /*
  739  * Internal Note: size_t is used instead of uint8_t to ensure alignment on platforms where
  740  * alignment matters.
  741  */
  742 //--------------------------------------------------------------------------------------------------
  743 #if LE_CONFIG_MEM_POOLS
  744 #  define LE_MEM_DEFINE_STATIC_POOL(name, numBlocks, objSize)             \
  745     static le_mem_Pool_t _mem_##name##Pool;                             \
  746     static size_t _mem_##name##Data[LE_MEM_POOL_WORDS(numBlocks, objSize)]
  747 #else
  748 #  define LE_MEM_DEFINE_STATIC_POOL(name, numBlocks, objSize)             \
  749     static le_mem_Pool_t _mem_##name##Pool
  750 #endif
  751 
  752 
  753 //--------------------------------------------------------------------------------------------------
  754 /**
  755  * Initialize an empty static memory pool.
  756  *
  757  * @return
  758  *      Reference to the memory pool object.
  759  *
  760  * @note
  761  *      This function cannot fail.
  762  */
  763 //--------------------------------------------------------------------------------------------------
  764 #if LE_CONFIG_MEM_POOLS
  765 #  define le_mem_InitStaticPool(name, numBlocks, objSize)                                   \
  766     (inline_static_assert(                                                                  \
  767         sizeof(_mem_##name##Data) == sizeof(size_t[LE_MEM_POOL_WORDS(numBlocks, objSize)]), \
  768         "initial pool size does not match definition"),                                     \
  769     _le_mem_InitStaticPool(STRINGIZE(LE_COMPONENT_NAME), #name, (numBlocks), (objSize),     \
  770                            &_mem_##name##Pool, _mem_##name##Data))
  771 #else
  772 #  define le_mem_InitStaticPool(name, numBlocks, objSize)                               \
  773     _le_mem_InitStaticPool(STRINGIZE(LE_COMPONENT_NAME), #name, (numBlocks), (objSize), \
  774                            &_mem_##name##Pool, NULL)
  775 #endif
  776 
  777 //--------------------------------------------------------------------------------------------------
  778 /**
  779  * Expands the size of a memory pool.
  780  *
  781  * @return  Reference to the memory pool object (the same value passed into it).
  782  *
  783  * @note    On failure, the process exits, so you don't have to worry about checking the returned
  784  *          reference for validity.
  785  */
  786 //--------------------------------------------------------------------------------------------------
  787 le_mem_PoolRef_t le_mem_ExpandPool
  788 (
  789     le_mem_PoolRef_t    pool,       ///< [IN] Pool to be expanded.
  790     size_t              numObjects  ///< [IN] Number of objects to add to the pool.
  791 );
  792 
  793 
  794 
  795 #if !LE_CONFIG_MEM_TRACE
  796     //----------------------------------------------------------------------------------------------
  797     /**
  798      * Attempts to allocate an object from a pool.
  799      *
  800      * @return
  801      *      Pointer to the allocated object, or NULL if the pool doesn't have any free objects
  802      *      to allocate.
  803      */
  804     //----------------------------------------------------------------------------------------------
  805     void* le_mem_TryAlloc
  806     (
  807         le_mem_PoolRef_t    pool    ///< [IN] Pool from which the object is to be allocated.
  808     );
  809 #else
  810     /// @cond HIDDEN_IN_USER_DOCS
  811     void* _le_mem_TryAlloc(le_mem_PoolRef_t pool);
  812     /// @endcond
  813 
  814 #   define le_mem_TryAlloc(pool)                                                                    \
  815         _le_mem_AllocTracer(pool,                                                                   \
  816                             _le_mem_TryAlloc,                                                       \
  817                             "le_mem_TryAlloc",                                                      \
  818                             STRINGIZE(LE_FILENAME),                                                 \
  819                             __FUNCTION__,                                                           \
  820                             __LINE__)
  821 
  822 #endif
  823 
  824 
  825 #if !LE_CONFIG_MEM_TRACE
  826     //----------------------------------------------------------------------------------------------
  827     /**
  828      * Allocates an object from a pool or logs a fatal error and terminates the process if the pool
  829      * doesn't have any free objects to allocate.
  830      *
  831      * @return Pointer to the allocated object.
  832      *
  833      * @note    On failure, the process exits, so you don't have to worry about checking the
  834      *          returned pointer for validity.
  835      */
  836     //----------------------------------------------------------------------------------------------
  837     void* le_mem_AssertAlloc
  838     (
  839         le_mem_PoolRef_t    pool    ///< [IN] Pool from which the object is to be allocated.
  840     );
  841 #else
  842     /// @cond HIDDEN_IN_USER_DOCS
  843     void* _le_mem_AssertAlloc(le_mem_PoolRef_t pool);
  844     /// @endcond
  845 
  846 #   define le_mem_AssertAlloc(pool)                                                                 \
  847         _le_mem_AllocTracer(pool,                                                                   \
  848                             _le_mem_AssertAlloc,                                                    \
  849                             "le_mem_AssertAlloc",                                                   \
  850                             STRINGIZE(LE_FILENAME),                                                 \
  851                             __FUNCTION__,                                                           \
  852                             __LINE__)
  853 #endif
  854 
  855 
  856 #if !LE_CONFIG_MEM_TRACE
  857     //----------------------------------------------------------------------------------------------
  858     /**
  859      * Allocates an object from a pool or logs a warning and expands the pool if the pool
  860      * doesn't have any free objects to allocate.
  861      *
  862      * @return  Pointer to the allocated object.
  863      *
  864      * @note    On failure, the process exits, so you don't have to worry about checking the
  865      *          returned pointer for validity.
  866      */
  867     //----------------------------------------------------------------------------------------------
  868     void* le_mem_ForceAlloc
  869     (
  870         le_mem_PoolRef_t    pool    ///< [IN] Pool from which the object is to be allocated.
  871     );
  872 #else
  873     /// @cond HIDDEN_IN_USER_DOCS
  874     void* _le_mem_ForceAlloc(le_mem_PoolRef_t pool);
  875     /// @endcond
  876 
  877 #   define le_mem_ForceAlloc(pool)                                                                  \
  878         _le_mem_AllocTracer(pool,                                                                   \
  879                             _le_mem_ForceAlloc,                                                     \
  880                             "le_mem_ForceAlloc",                                                    \
  881                             STRINGIZE(LE_FILENAME),                                                 \
  882                             __FUNCTION__,                                                           \
  883                             __LINE__)
  884 #endif
  885 
  886 
  887 #if !LE_CONFIG_MEM_TRACE
  888     //----------------------------------------------------------------------------------------------
  889     /**
  890      * Attempts to allocate an object from a pool.
  891      *
  892      * @return
  893      *      Pointer to the allocated object, or NULL if the pool doesn't have any free objects
  894      *      to allocate.
  895      */
  896     //----------------------------------------------------------------------------------------------
  897     void* le_mem_TryVarAlloc
  898     (
  899         le_mem_PoolRef_t    pool,         ///< [IN] Pool from which the object is to be allocated.
  900         size_t              size          ///< [IN] The size of block to allocate
  901     );
  902 #else
  903     /// @cond HIDDEN_IN_USER_DOCS
  904     void* _le_mem_TryVarAlloc(le_mem_PoolRef_t pool, size_t size);
  905     /// @endcond
  906 
  907 #   define le_mem_TryVarAlloc(pool, size)                               \
  908          _le_mem_VarAllocTracer(pool,                                   \
  909                                 size,                                   \
  910                                 _le_mem_TryVarAlloc,                    \
  911                                 "le_mem_TryVarAlloc",                   \
  912                                 STRINGIZE(LE_FILENAME),                 \
  913                                 __FUNCTION__,                           \
  914                                 __LINE__)
  915 
  916 #endif
  917 
  918 
  919 #if !LE_CONFIG_MEM_TRACE
  920     //----------------------------------------------------------------------------------------------
  921     /**
  922      * Allocates an object from a pool or logs a fatal error and terminates the process if the pool
  923      * doesn't have any free objects to allocate.
  924      *
  925      * @return Pointer to the allocated object.
  926      *
  927      * @note    On failure, the process exits, so you don't have to worry about checking the
  928      *          returned pointer for validity.
  929      */
  930     //----------------------------------------------------------------------------------------------
  931     void* le_mem_AssertVarAlloc
  932     (
  933         le_mem_PoolRef_t    pool,        ///< [IN] Pool from which the object is to be allocated.
  934         size_t              size         ///< [IN] The size of block to allocate
  935     );
  936 #else
  937     /// @cond HIDDEN_IN_USER_DOCS
  938     void* _le_mem_AssertVarAlloc(le_mem_PoolRef_t pool, size_t size);
  939     /// @endcond
  940 
  941 #   define le_mem_AssertVarAlloc(pool, size)                            \
  942         _le_mem_VarAllocTracer(pool,                                    \
  943                                size,                                    \
  944                                _le_mem_AssertVarAlloc,                  \
  945                                "le_mem_AssertVarAlloc",                 \
  946                                STRINGIZE(LE_FILENAME),                  \
  947                                __FUNCTION__,                            \
  948                                __LINE__)
  949 #endif
  950 
  951 
  952 #if !LE_CONFIG_MEM_TRACE
  953     //----------------------------------------------------------------------------------------------
  954     /**
  955      * Allocates an object from a pool or logs a warning and expands the pool if the pool
  956      * doesn't have any free objects to allocate.
  957      *
  958      * @return  Pointer to the allocated object.
  959      *
  960      * @note    On failure, the process exits, so you don't have to worry about checking the
  961      *          returned pointer for validity.
  962      */
  963     //----------------------------------------------------------------------------------------------
  964     void* le_mem_ForceVarAlloc
  965     (
  966         le_mem_PoolRef_t    pool,        ///< [IN] Pool from which the object is to be allocated.
  967         size_t              size         ///< [IN] The size of block to allocate
  968     );
  969 #else
  970     /// @cond HIDDEN_IN_USER_DOCS
  971     void* _le_mem_ForceVarAlloc(le_mem_PoolRef_t pool, size_t size);
  972     /// @endcond
  973 
  974 #   define le_mem_ForceVarAlloc(pool, size)                             \
  975         _le_mem_VarAllocTracer(pool,                                    \
  976                                size,                                    \
  977                                _le_mem_ForceVarAlloc,                   \
  978                                "le_mem_ForceVarAlloc",                  \
  979                                STRINGIZE(LE_FILENAME),                  \
  980                                __FUNCTION__,                            \
  981                                __LINE__)
  982 #endif
  983 
  984 
  985 //--------------------------------------------------------------------------------------------------
  986 /**
  987  * Sets the number of objects that are added when le_mem_ForceAlloc expands the pool.
  988  *
  989  * @return
  990  *      Nothing.
  991  *
  992  * @note
  993  *      The default value is one.
  994  */
  995 //--------------------------------------------------------------------------------------------------
  996 void le_mem_SetNumObjsToForce
  997 (
  998     le_mem_PoolRef_t    pool,       ///< [IN] Pool to set the number of objects for.
  999     size_t              numObjects  ///< [IN] Number of objects that is added when
 1000                                     ///       le_mem_ForceAlloc expands the pool.
 1001 );
 1002 
 1003 
 1004 #if !LE_CONFIG_MEM_TRACE
 1005     //----------------------------------------------------------------------------------------------
 1006     /**
 1007      * Releases an object.  If the object's reference count has reached zero, it will be destructed
 1008      * and its memory will be put back into the pool for later reuse.
 1009      *
 1010      * @return
 1011      *      Nothing.
 1012      *
 1013      * @warning
 1014      *      - <b>Don't EVER access an object after releasing it.</b>  It might not exist anymore.
 1015      *      - If the object has a destructor accessing a data structure shared by multiple
 1016      *        threads, ensure you hold the mutex (or take other measures to prevent races) before
 1017      *        releasing the object.
 1018      */
 1019     //----------------------------------------------------------------------------------------------
 1020     void le_mem_Release
 1021     (
 1022         void*   objPtr  ///< [IN] Pointer to the object to be released.
 1023     );
 1024 #else
 1025     /// @cond HIDDEN_IN_USER_DOCS
 1026     void _le_mem_Release(void* objPtr);
 1027     /// @endcond
 1028 
 1029 #   define le_mem_Release(objPtr)                                                                   \
 1030             _le_mem_Trace(_le_mem_GetBlockPool(objPtr),                                             \
 1031                           STRINGIZE(LE_FILENAME),                                                   \
 1032                           __FUNCTION__,                                                             \
 1033                           __LINE__,                                                                 \
 1034                           "le_mem_Release",                                                         \
 1035                           (objPtr));                                                                \
 1036             _le_mem_Release(objPtr);
 1037 #endif
 1038 
 1039 
 1040 #if !LE_CONFIG_MEM_TRACE
 1041     //----------------------------------------------------------------------------------------------
 1042     /**
 1043      * Increments the reference count on an object by 1.
 1044      *
 1045      * See @ref mem_ref_counting for more information.
 1046      *
 1047      * @return
 1048      *      Nothing.
 1049      */
 1050     //----------------------------------------------------------------------------------------------
 1051     void le_mem_AddRef
 1052     (
 1053         void*   objPtr  ///< [IN] Pointer to the object.
 1054     );
 1055 #else
 1056     /// @cond HIDDEN_IN_USER_DOCS
 1057     void _le_mem_AddRef(void* objPtr);
 1058     /// @endcond
 1059 
 1060 #   define le_mem_AddRef(objPtr)                                                                    \
 1061         _le_mem_Trace(_le_mem_GetBlockPool(objPtr),                                                 \
 1062                       STRINGIZE(LE_FILENAME),                                                       \
 1063                       __FUNCTION__,                                                                 \
 1064                       __LINE__,                                                                     \
 1065                       "le_mem_AddRef",                                                              \
 1066                       (objPtr));                                                                    \
 1067         _le_mem_AddRef(objPtr);
 1068 #endif
 1069 
 1070 //--------------------------------------------------------------------------------------------------
 1071 /**
 1072  * Fetches the size of a block (in bytes).
 1073  *
 1074  * @return
 1075  *      Object size, in bytes.
 1076  */
 1077 //--------------------------------------------------------------------------------------------------
 1078 size_t le_mem_GetBlockSize
 1079 (
 1080     void* objPtr                 ///< [IN] Pointer to the object to get size of.
 1081 );
 1082 
 1083 //----------------------------------------------------------------------------------------------
 1084 /**
 1085  * Fetches the reference count on an object.
 1086  *
 1087  * See @ref mem_ref_counting for more information.
 1088  *
 1089  * @warning If using this in a multi-threaded application that shares memory pool objects
 1090  *          between threads, steps must be taken to coordinate the threads (e.g., using a mutex)
 1091  *          to ensure that the reference count value fetched remains correct when it is used.
 1092  *
 1093  * @return
 1094  *      The reference count on the object.
 1095  */
 1096 //----------------------------------------------------------------------------------------------
 1097 size_t le_mem_GetRefCount
 1098 (
 1099     void*   objPtr  ///< [IN] Pointer to the object.
 1100 );
 1101 
 1102 
 1103 //--------------------------------------------------------------------------------------------------
 1104 /**
 1105  * Sets the destructor function for a specified pool.
 1106  *
 1107  * See @ref mem_destructors for more information.
 1108  *
 1109  * @return
 1110  *      Nothing.
 1111  */
 1112 //--------------------------------------------------------------------------------------------------
 1113 void le_mem_SetDestructor
 1114 (
 1115     le_mem_PoolRef_t    pool,       ///< [IN] The pool.
 1116     le_mem_Destructor_t destructor  ///< [IN] Destructor function.
 1117 );
 1118 
 1119 
 1120 //--------------------------------------------------------------------------------------------------
 1121 /**
 1122  * Fetches the statistics for a specified pool.
 1123  *
 1124  * @return
 1125  *      Nothing.  Uses output parameter instead.
 1126  */
 1127 //--------------------------------------------------------------------------------------------------
 1128 void le_mem_GetStats
 1129 (
 1130     le_mem_PoolRef_t    pool,       ///< [IN] Pool where stats are to be fetched.
 1131     le_mem_PoolStats_t* statsPtr    ///< [OUT] Pointer to where the stats will be stored.
 1132 );
 1133 
 1134 
 1135 //--------------------------------------------------------------------------------------------------
 1136 /**
 1137  * Resets the statistics for a specified pool.
 1138  *
 1139  * @return
 1140  *      Nothing.
 1141  */
 1142 //--------------------------------------------------------------------------------------------------
 1143 void le_mem_ResetStats
 1144 (
 1145     le_mem_PoolRef_t    pool        ///< [IN] Pool where stats are to be reset.
 1146 );
 1147 
 1148 
 1149 //--------------------------------------------------------------------------------------------------
 1150 /**
 1151  * Gets the memory pool's name, including the component name prefix.
 1152  *
 1153  * If the pool were given the name "myPool" and the component that it belongs to is called
 1154  * "myComponent", then the full pool name returned by this function would be "myComponent.myPool".
 1155  *
 1156  * @return
 1157  *      LE_OK if successful.
 1158  *      LE_OVERFLOW if the name was truncated to fit in the provided buffer.
 1159  */
 1160 //--------------------------------------------------------------------------------------------------
 1161 le_result_t le_mem_GetName
 1162 (
 1163     le_mem_PoolRef_t    pool,       ///< [IN] The memory pool.
 1164     char*               namePtr,    ///< [OUT] Buffer to store the name of the memory pool.
 1165     size_t              bufSize     ///< [IN] Size of the buffer namePtr points to.
 1166 );
 1167 
 1168 
 1169 //--------------------------------------------------------------------------------------------------
 1170 /**
 1171  * Checks if the specified pool is a sub-pool.
 1172  *
 1173  * @return
 1174  *      true if it is a sub-pool.
 1175  *      false if it is not a sub-pool.
 1176  */
 1177 //--------------------------------------------------------------------------------------------------
 1178 const bool le_mem_IsSubPool
 1179 (
 1180     le_mem_PoolRef_t    pool        ///< [IN] The memory pool.
 1181 );
 1182 
 1183 
 1184 //--------------------------------------------------------------------------------------------------
 1185 /**
 1186  * Fetches the number of objects a specified pool can hold (this includes both the number of
 1187  * free and in-use objects).
 1188  *
 1189  * @return
 1190  *      Total number of objects.
 1191  */
 1192 //--------------------------------------------------------------------------------------------------
 1193 size_t le_mem_GetObjectCount
 1194 (
 1195     le_mem_PoolRef_t    pool        ///< [IN] Pool where number of objects is to be fetched.
 1196 );
 1197 
 1198 
 1199 //--------------------------------------------------------------------------------------------------
 1200 /**
 1201  * Fetches the size of the objects in a specified pool (in bytes).
 1202  *
 1203  * @return
 1204  *      Object size, in bytes.
 1205  */
 1206 //--------------------------------------------------------------------------------------------------
 1207 size_t le_mem_GetObjectSize
 1208 (
 1209     le_mem_PoolRef_t    pool        ///< [IN] Pool where object size is to be fetched.
 1210 );
 1211 
 1212 
 1213 //--------------------------------------------------------------------------------------------------
 1214 /**
 1215  * Fetches the total size of the object including all the memory overhead in a given pool (in bytes).
 1216  *
 1217  * @return
 1218  *      Total object memory size, in bytes.
 1219  */
 1220 //--------------------------------------------------------------------------------------------------
 1221 size_t le_mem_GetObjectFullSize
 1222 (
 1223     le_mem_PoolRef_t    pool        ///< [IN] The pool whose object memory size is to be fetched.
 1224 );
 1225 
 1226 
 1227 #if LE_CONFIG_MEM_POOL_NAMES_ENABLED
 1228 //--------------------------------------------------------------------------------------------------
 1229 /** @cond HIDDEN_IN_USER_DOCS
 1230  *
 1231  * Internal function used to implement le_mem_FindPool() with automatic component scoping
 1232  * of pool names.
 1233  */
 1234 //--------------------------------------------------------------------------------------------------
 1235 le_mem_PoolRef_t _le_mem_FindPool
 1236 (
 1237     const char* componentName,  ///< [IN] Name of the component.
 1238     const char* name            ///< [IN] Name of the pool inside the component.
 1239 );
 1240 /// @endcond
 1241 //--------------------------------------------------------------------------------------------------
 1242 /**
 1243  * Finds a pool based on the pool's name.
 1244  *
 1245  * @return
 1246  *      Reference to the pool, or NULL if the pool doesn't exist.
 1247  */
 1248 //--------------------------------------------------------------------------------------------------
 1249 static inline le_mem_PoolRef_t le_mem_FindPool
 1250 (
 1251     const char* name            ///< [IN] Name of the pool inside the component.
 1252 )
 1253 {
 1254     return _le_mem_FindPool(STRINGIZE(LE_COMPONENT_NAME), name);
 1255 }
 1256 #else
 1257 //--------------------------------------------------------------------------------------------------
 1258 /**
 1259  * Finds a pool based on the pool's name.
 1260  *
 1261  * @return
 1262  *      Reference to the pool, or NULL if the pool doesn't exist.
 1263  */
 1264 //--------------------------------------------------------------------------------------------------
 1265 LE_DECLARE_INLINE le_mem_PoolRef_t le_mem_FindPool
 1266 (
 1267     const char* name            ///< [IN] Name of the pool inside the component.
 1268 )
 1269 {
 1270     return NULL;
 1271 }
 1272 #endif /* end LE_CONFIG_MEM_POOL_NAMES_ENABLED */
 1273 
 1274 
 1275 #if LE_CONFIG_MEM_POOL_NAMES_ENABLED
 1276 //--------------------------------------------------------------------------------------------------
 1277 /** @cond HIDDEN_IN_USER_DOCS
 1278  *
 1279  * Internal function used to implement le_mem_CreateSubPool() with automatic component scoping
 1280  * of pool names.
 1281  */
 1282 //--------------------------------------------------------------------------------------------------
 1283 le_mem_PoolRef_t _le_mem_CreateSubPool
 1284 (
 1285     le_mem_PoolRef_t    superPool,  ///< [IN] Super-pool.
 1286     const char*         componentName,  ///< [IN] Name of the component.
 1287     const char*         name,       ///< [IN] Name of the sub-pool (will be copied into the
 1288                                     ///   sub-pool).
 1289     size_t              numObjects  ///< [IN] Number of objects to take from the super-pool.
 1290 );
 1291 /// @endcond
 1292 //--------------------------------------------------------------------------------------------------
 1293 /**
 1294  * Creates a sub-pool.
 1295  *
 1296  * See @ref mem_sub_pools for more information.
 1297  *
 1298  * @return
 1299  *      Reference to the sub-pool.
 1300  */
 1301 //--------------------------------------------------------------------------------------------------
 1302 static inline le_mem_PoolRef_t le_mem_CreateSubPool
 1303 (
 1304     le_mem_PoolRef_t    superPool,      ///< [IN] Super-pool.
 1305     const char*         name,           ///< [IN] Name of the sub-pool (will be copied into the
 1306                                         ///   sub-pool).
 1307     size_t              numObjects      ///< [IN] Number of objects to take from the super-pool.
 1308 )
 1309 {
 1310     return _le_mem_CreateSubPool(superPool, STRINGIZE(LE_COMPONENT_NAME), name, numObjects);
 1311 }
 1312 #else /* if not LE_CONFIG_MEM_POOL_NAMES_ENABLED */
 1313 //--------------------------------------------------------------------------------------------------
 1314 /** @cond HIDDEN_IN_USER_DOCS
 1315  *
 1316  * Internal function used to implement le_mem_CreateSubPool() with automatic component scoping
 1317  * of pool names.
 1318  */
 1319 //--------------------------------------------------------------------------------------------------
 1320 le_mem_PoolRef_t _le_mem_CreateSubPool
 1321 (
 1322     le_mem_PoolRef_t    superPool,      ///< [IN] Super-pool.
 1323     size_t              numObjects      ///< [IN] Number of objects to take from the super-pool.
 1324 );
 1325 /// @endcond
 1326 //--------------------------------------------------------------------------------------------------
 1327 /**
 1328  * Creates a sub-pool.
 1329  *
 1330  * See @ref mem_sub_pools for more information.
 1331  *
 1332  * @return
 1333  *      Reference to the sub-pool.
 1334  */
 1335 //--------------------------------------------------------------------------------------------------
 1336 LE_DECLARE_INLINE le_mem_PoolRef_t le_mem_CreateSubPool
 1337 (
 1338     le_mem_PoolRef_t    superPool,      ///< [IN] Super-pool.
 1339     const char*         name,           ///< [IN] Name of the sub-pool (will be copied into the
 1340                                         ///   sub-pool).
 1341     size_t              numObjects      ///< [IN] Number of objects to take from the super-pool.
 1342 )
 1343 {
 1344     return _le_mem_CreateSubPool(superPool, numObjects);
 1345 }
 1346 #endif /* end LE_CONFIG_MEM_POOL_NAMES_ENABLED */
 1347 
 1348 
 1349 #if LE_CONFIG_MEM_POOL_NAMES_ENABLED
 1350 //--------------------------------------------------------------------------------------------------
 1351 /** @cond HIDDEN_IN_USER_DOCS
 1352  *
 1353  * Internal function used to implement le_mem_CreateSubPool() with automatic component scoping
 1354  * of pool names.
 1355  */
 1356 //--------------------------------------------------------------------------------------------------
 1357 le_mem_PoolRef_t _le_mem_CreateReducedPool
 1358 (
 1359     le_mem_PoolRef_t    superPool,      ///< [IN] Super-pool.
 1360     const char*         componentName,  ///< [IN] Name of the component.
 1361     const char*         name,           ///< [IN] Name of the sub-pool (will be copied into the
 1362                                         ///   sub-pool).
 1363     size_t              numObjects,     ///< [IN] Number of objects to take from the super-pool.
 1364     size_t              objSize         ///< [IN] Minimum size of objects in the subpool.
 1365 );
 1366 /// @endcond
 1367 //--------------------------------------------------------------------------------------------------
 1368 /**
 1369  * Creates a sub-pool of smaller objects.
 1370  *
 1371  * See @ref mem_reduced_pools for more information.
 1372  *
 1373  * @return
 1374  *      Reference to the sub-pool.
 1375  */
 1376 //--------------------------------------------------------------------------------------------------
 1377 static inline le_mem_PoolRef_t le_mem_CreateReducedPool
 1378 (
 1379     le_mem_PoolRef_t    superPool,      ///< [IN] Super-pool.
 1380     const char*         name,           ///< [IN] Name of the sub-pool (will be copied into the
 1381                                         ///   sub-pool).
 1382     size_t              numObjects,     ///< [IN] Minimum number of objects in the subpool
 1383                                         ///< by default.
 1384     size_t              objSize         ///< [IN] Minimum size of objects in the subpool.
 1385 )
 1386 {
 1387     return _le_mem_CreateReducedPool(superPool, STRINGIZE(LE_COMPONENT_NAME), name, numObjects, objSize);
 1388 }
 1389 #else /* if not LE_CONFIG_MEM_POOL_NAMES_ENABLED */
 1390 //--------------------------------------------------------------------------------------------------
 1391 /** @cond HIDDEN_IN_USER_DOCS
 1392  *
 1393  * Internal function used to implement le_mem_CreateSubPool() with automatic component scoping
 1394  * of pool names.
 1395  */
 1396 //--------------------------------------------------------------------------------------------------
 1397 le_mem_PoolRef_t _le_mem_CreateReducedPool
 1398 (
 1399     le_mem_PoolRef_t    superPool,      ///< [IN] Super-pool.
 1400     size_t              numObjects,     ///< [IN] Minimum number of objects in the subpool
 1401                                         ///< by default.
 1402     size_t              objSize         ///< [IN] Minimum size of objects in the subpool.
 1403 );
 1404 /// @endcond
 1405 //--------------------------------------------------------------------------------------------------
 1406 /**
 1407  * Creates a sub-pool of smaller objects.
 1408  *
 1409  * See @ref mem_reduced_pools for more information.
 1410  *
 1411  * @return
 1412  *      Reference to the sub-pool.
 1413  */
 1414 //--------------------------------------------------------------------------------------------------
 1415 LE_DECLARE_INLINE le_mem_PoolRef_t le_mem_CreateReducedPool
 1416 (
 1417     le_mem_PoolRef_t    superPool,      ///< [IN] Super-pool.
 1418     const char*         name,           ///< [IN] Name of the sub-pool (will be copied into the
 1419                                         ///   sub-pool).
 1420     size_t              numObjects,     ///< [IN] Minimum number of objects in the subpool
 1421                                         ///< by default.
 1422     size_t              objSize         ///< [IN] Minimum size of objects in the subpool.
 1423 )
 1424 {
 1425     return _le_mem_CreateReducedPool(superPool, numObjects, objSize);
 1426 }
 1427 #endif /* end LE_CONFIG_MEM_POOL_NAMES_ENABLED */
 1428 
 1429 
 1430 //--------------------------------------------------------------------------------------------------
 1431 /**
 1432  * Deletes a sub-pool.
 1433  *
 1434  * See @ref mem_sub_pools for more information.
 1435  *
 1436  * @return
 1437  *      Nothing.
 1438  */
 1439 //--------------------------------------------------------------------------------------------------
 1440 void le_mem_DeleteSubPool
 1441 (
 1442     le_mem_PoolRef_t    subPool     ///< [IN] Sub-pool to be deleted.
 1443 );
 1444 
 1445 #if LE_CONFIG_RTOS
 1446 //--------------------------------------------------------------------------------------------------
 1447 /**
 1448  * Compress memory pools ready for hibernate-to-RAM
 1449  *
 1450  * This compresses the memory pools ready for hibernation.  All Legato tasks must remain
 1451  * suspended until after le_mem_Resume() is called.
 1452  *
 1453  * @return Nothing
 1454  */
 1455 //--------------------------------------------------------------------------------------------------
 1456 void le_mem_Hibernate
 1457 (
 1458     void **freeStartPtr,     ///< [OUT] Beginning of unused memory which does not need to be
 1459                              ///<       preserved in hibernation
 1460     void **freeEndPtr        ///< [OUT] End of unused memory
 1461 );
 1462 
 1463 //--------------------------------------------------------------------------------------------------
 1464 /**
 1465  * Decompress memory pools after waking from hibernate-to-RAM
 1466  *
 1467  * This decompresses memory pools after hibernation.  After this function returns, Legato tasks
 1468  * may be resumed.
 1469  *
 1470  * @return Nothing
 1471  */
 1472 //--------------------------------------------------------------------------------------------------
 1473 void le_mem_Resume
 1474 (
 1475     void
 1476 );
 1477 
 1478 #endif /* end LE_CONFIG_RTOS */
 1479 
 1480 
 1481 #endif // LEGATO_MEM_INCLUDE_GUARD
le_mem_Pool_t::numBlocksToForce
size_t numBlocksToForce
Definition: le_mem.h:519
le_mem_PoolStats_t::numFree
size_t numFree
Number of free objects currently available in this pool. 
Definition: le_mem.h:554
le_mem_Pool_t::numAllocations
uint64_t numAllocations
Definition: le_mem.h:506
le_mem_TryAlloc
void * le_mem_TryAlloc(le_mem_PoolRef_t pool)
le_mem_Pool_t::freeList
le_sls_List_t freeList
List of free memory blocks. 
Definition: le_mem.h:511
le_mem_TryVarAlloc
void * le_mem_TryVarAlloc(le_mem_PoolRef_t pool, size_t size)
le_mem_ExpandPool
le_mem_PoolRef_t le_mem_ExpandPool(le_mem_PoolRef_t pool, size_t numObjects)
le_result_t
le_result_t
Definition: le_basics.h:35
le_mem_AssertAlloc
void * le_mem_AssertAlloc(le_mem_PoolRef_t pool)
le_mem_GetStats
void le_mem_GetStats(le_mem_PoolRef_t pool, le_mem_PoolStats_t *statsPtr)
le_mem_Resume
void le_mem_Resume(void)
le_mem_IsSubPool
const bool le_mem_IsSubPool(le_mem_PoolRef_t pool)
le_mem_PoolStats_t::numBlocksInUse
size_t numBlocksInUse
Number of currently allocated blocks. 
Definition: le_mem.h:550
le_mem_Pool_t::totalBlocks
size_t totalBlocks
Definition: le_mem.h:516
le_mem_Pool_t::superPoolPtr
struct le_mem_Pool * superPoolPtr
Definition: le_mem.h:500
STRINGIZE
#define STRINGIZE(x)
Definition: le_basics.h:207
le_mem_SetDestructor
void le_mem_SetDestructor(le_mem_PoolRef_t pool, le_mem_Destructor_t destructor)
le_mem_AssertVarAlloc
void * le_mem_AssertVarAlloc(le_mem_PoolRef_t pool, size_t size)
le_mem_PoolStats_t::numAllocs
uint64_t numAllocs
Number of times an object has been allocated from this pool. 
Definition: le_mem.h:553
le_mem_Pool_t::maxNumBlocksUsed
size_t maxNumBlocksUsed
Maximum number of allocated blocks at any one time. 
Definition: le_mem.h:508
le_mem_PoolStats_t::maxNumBlocksUsed
size_t maxNumBlocksUsed
Maximum number of allocated blocks at any one time. 
Definition: le_mem.h:551
le_mem_ForceVarAlloc
void * le_mem_ForceVarAlloc(le_mem_PoolRef_t pool, size_t size)
le_mem_ResetStats
void le_mem_ResetStats(le_mem_PoolRef_t pool)
le_mem_PoolStats_t::numOverflows
size_t numOverflows
Number of times le_mem_ForceAlloc() had to expand the pool. 
Definition: le_mem.h:552
le_mem_CreateReducedPool
static le_mem_PoolRef_t le_mem_CreateReducedPool(le_mem_PoolRef_t superPool, const char *name, size_t numObjects, size_t objSize)
Definition: le_mem.h:1378
le_mem_SetNumObjsToForce
void le_mem_SetNumObjsToForce(le_mem_PoolRef_t pool, size_t numObjects)
le_mem_Pool_t::numOverflows
size_t numOverflows
Number of times le_mem_ForceAlloc() had to expand pool. 
Definition: le_mem.h:505
le_mem_DeleteSubPool
void le_mem_DeleteSubPool(le_mem_PoolRef_t subPool)
le_mem_PoolRef_t
struct le_mem_Pool * le_mem_PoolRef_t
Definition: le_mem.h:540
le_mem_GetName
le_result_t le_mem_GetName(le_mem_PoolRef_t pool, char *namePtr, size_t bufSize)
le_mem_Release
void le_mem_Release(void *objPtr)
le_mem_PoolStats_t
Definition: le_mem.h:548
le_mem_FindPool
static le_mem_PoolRef_t le_mem_FindPool(const char *name)
Definition: le_mem.h:1250
le_mem_Pool_t::blockSize
size_t blockSize
Number of bytes in a block, including all overhead. 
Definition: le_mem.h:515
le_mem_Destructor_t
void(* le_mem_Destructor_t)(void *objPtr)
Definition: le_mem.h:482
le_mem_GetObjectCount
size_t le_mem_GetObjectCount(le_mem_PoolRef_t pool)
le_mem_Pool_t
Definition: le_mem.h:497
le_sls_List_t
Definition: le_singlyLinkedList.h:201
le_mem_GetObjectFullSize
size_t le_mem_GetObjectFullSize(le_mem_PoolRef_t pool)
le_mem_Pool_t::destructor
le_mem_Destructor_t destructor
The destructor for objects in this pool. 
Definition: le_mem.h:526
le_mem_GetBlockSize
size_t le_mem_GetBlockSize(void *objPtr)
le_mem_CreatePool
static le_mem_PoolRef_t le_mem_CreatePool(const char *name, size_t objSize)
Definition: le_mem.h:672
le_mem_GetObjectSize
size_t le_mem_GetObjectSize(le_mem_PoolRef_t pool)
le_dls_Link_t
Definition: le_doublyLinkedList.h:200
le_mem_Pool_t::poolLink
le_dls_Link_t poolLink
This pool&#39;s link in the list of memory pools. 
Definition: le_mem.h:499
le_mem_CreateSubPool
static le_mem_PoolRef_t le_mem_CreateSubPool(le_mem_PoolRef_t superPool, const char *name, size_t numObjects)
Definition: le_mem.h:1303
le_mem_AddRef
void le_mem_AddRef(void *objPtr)
le_mem_ForceAlloc
void * le_mem_ForceAlloc(le_mem_PoolRef_t pool)
le_mem_Pool_t::userDataSize
size_t userDataSize
Size of the object requested by the client in bytes. 
Definition: le_mem.h:514
le_mem_Hibernate
void le_mem_Hibernate(void **freeStartPtr, void **freeEndPtr)
le_mem_Pool_t::numBlocksInUse
size_t numBlocksInUse
Number of currently allocated blocks. 
Definition: le_mem.h:518
le_mem_GetRefCount
size_t le_mem_GetRefCount(void *objPtr)
LE_DECLARE_INLINE
#define LE_DECLARE_INLINE
Definition: le_basics.h:274