mem.h

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/* PipeWire */
/* SPDX-FileCopyrightText: Copyright © 2018 Wim Taymans */
/* SPDX-License-Identifier: MIT */
 
#ifndef PIPEWIRE_MEM_H
#define PIPEWIRE_MEM_H
 
#include <spa/utils/overflow.h>
#include <pipewire/properties.h>
 
struct spa_hook;
 
#ifdef __cplusplus
extern "C" {
#endif
 
#ifndef PW_API_MEM
#define PW_API_MEM static inline
#endif



enum pw_memblock_flags {
        PW_MEMBLOCK_FLAG_NONE =            0,
        PW_MEMBLOCK_FLAG_READABLE =    (1 << 0),       
        PW_MEMBLOCK_FLAG_WRITABLE =    (1 << 1),       
        PW_MEMBLOCK_FLAG_SEAL =            (1 << 2),       
        PW_MEMBLOCK_FLAG_MAP =              (1 << 3),       
        PW_MEMBLOCK_FLAG_DONT_CLOSE =        (1 << 4),       
        PW_MEMBLOCK_FLAG_DONT_NOTIFY =      (1 << 5),       
        PW_MEMBLOCK_FLAG_UNMAPPABLE =        (1 << 6),       
 
        PW_MEMBLOCK_FLAG_READWRITE = PW_MEMBLOCK_FLAG_READABLE | PW_MEMBLOCK_FLAG_WRITABLE,
};
 
enum pw_memmap_flags {
        PW_MEMMAP_FLAG_NONE =                0,
        PW_MEMMAP_FLAG_READ =                (1 << 0),       
        PW_MEMMAP_FLAG_WRITE =              (1 << 1),       
        PW_MEMMAP_FLAG_TWICE =              (1 << 2),       

        PW_MEMMAP_FLAG_PRIVATE =  (1 << 3),       
        PW_MEMMAP_FLAG_LOCKED =            (1 << 4),       
        PW_MEMMAP_FLAG_READWRITE = PW_MEMMAP_FLAG_READ | PW_MEMMAP_FLAG_WRITE,
};
 
struct pw_memchunk;

struct pw_mempool {
        struct pw_properties *props;
};

struct pw_memblock {
        struct pw_mempool *pool;  
        uint32_t id;                  
        int ref;                     
        uint32_t flags;                    
        uint32_t type;                      
        int fd;                               
        uint32_t size;                      
        struct pw_memmap *map;              
};

struct pw_memmap {
        struct pw_memblock *block;      
        void *ptr;                   
        uint32_t flags;                    
        uint32_t offset;          
        uint32_t size;                      
        uint32_t tag[5];             
};
 
struct pw_mempool_events {
#define PW_VERSION_MEMPOOL_EVENTS       0
        uint32_t version;

        void (*destroy) (void *data);

        /** a new memory block is added to the pool */
        void (*added) (void *data, struct pw_memblock *block);

        void (*removed) (void *data, struct pw_memblock *block);
};

struct pw_mempool *pw_mempool_new(struct pw_properties *props);

void pw_mempool_add_listener(struct pw_mempool *pool,
                            struct spa_hook *listener,
                            const struct pw_mempool_events *events,
                            void *data);

void pw_mempool_clear(struct pw_mempool *pool);

void pw_mempool_destroy(struct pw_mempool *pool);
 

struct pw_memblock * pw_mempool_alloc(struct pw_mempool *pool,
                enum pw_memblock_flags flags, uint32_t type, size_t size);

struct pw_memblock * pw_mempool_import_block(struct pw_mempool *pool,
                struct pw_memblock *mem);

struct pw_memblock * pw_mempool_import(struct pw_mempool *pool,
                enum pw_memblock_flags flags, uint32_t type, int fd);

void pw_memblock_free(struct pw_memblock *mem);

PW_API_MEM void pw_memblock_unref(struct pw_memblock *mem)
{
        if (--mem->ref == 0)
                pw_memblock_free(mem);
}

int pw_mempool_remove_id(struct pw_mempool *pool, uint32_t id);

struct pw_memblock * pw_mempool_find_ptr(struct pw_mempool *pool, const void *ptr);

struct pw_memblock * pw_mempool_find_id(struct pw_mempool *pool, uint32_t id);

struct pw_memblock * pw_mempool_find_fd(struct pw_mempool *pool, int fd);
 

struct pw_memmap * pw_memblock_map(struct pw_memblock *block,
                enum pw_memmap_flags flags, uint32_t offset, uint32_t size,
                uint32_t tag[5]);

struct pw_memmap * pw_mempool_map_id(struct pw_mempool *pool, uint32_t id,
                enum pw_memmap_flags flags, uint32_t offset, uint32_t size,
                uint32_t tag[5]);
 
struct pw_memmap * pw_mempool_import_map(struct pw_mempool *pool,
                struct pw_mempool *other, void *data, uint32_t size, uint32_t tag[5]);

struct pw_memmap * pw_mempool_find_tag(struct pw_mempool *pool, uint32_t tag[5], size_t size);

int pw_memmap_free(struct pw_memmap *map);
 

struct pw_map_range {
        uint32_t start;         
        uint32_t offset;  
        uint32_t size;              
};
 
#define PW_MAP_RANGE_INIT (struct pw_map_range){ 0, }

/** Calculate parameters to mmap() memory into \a range so that
 * \a size bytes at \a offset can be mapped with mmap().
 * Returns 0 on success, -EOVERFLOW if offset + size overflows. */
PW_API_MEM int pw_map_range_init(struct pw_map_range *range,
                                     uint32_t offset, uint32_t size,
                                     uint32_t page_size)
{
        uint32_t sum, tmp;
        range->offset = SPA_ROUND_DOWN_N(offset, page_size);
        range->start = offset - range->offset;
        if (spa_overflow_add(range->start, size, &sum))
                return -EOVERFLOW;
        /* Check that rounding up to page_size won't overflow */
        if (spa_overflow_add(sum, page_size - 1, &tmp))
                return -EOVERFLOW;
        range->size = SPA_ROUND_UP_N(sum, page_size);
        return 0;
}

 
#ifdef __cplusplus
}
#endif
 
#endif /* PIPEWIRE_MEM_H */