#endif
#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */
/**
* @file apr_mmap.h
* @brief APR MMAP routines
*/
/**
* @defgroup APR_MMAP MMAP (Memory Map) Routines
* @ingroup APR
* @{
*/
#define APR_MMAP_READ 1
#define APR_MMAP_WRITE 2
typedef struct apr_mmap_t apr_mmap_t;
/**
* @remark
* As far as I can tell the only really sane way to store an MMAP is as a
* void * and a length. BeOS requires this area_id, but that's just a little
* something extra. I am exposing this type, because it doesn't make much
* sense to keep it private, and opening it up makes some stuff easier in
* Apache.
*/
/** The MMAP structure */
struct apr_mmap_t {
/** The pool the mmap structure was allocated out of. */
apr_pool_t *cntxt;
#ifdef BEOS
/** An area ID. Only valid on BeOS */
area_id area;
#endif
#ifdef WIN32
/** The handle of the file mapping */
HANDLE mhandle;
/** The start of the real memory page area (mapped view) */
void *mv;
/** The physical start, size and offset */
apr_off_t pstart;
apr_size_t psize;
apr_off_t poffset;
#endif
/** The start of the memory mapped area */
void *mm;
/** The amount of data in the mmap */
apr_size_t size;
/** Whether this object is reponsible for doing the munmap */
int is_owner;
};
#if APR_HAS_MMAP || defined(DOXYGEN)
/* Files have to be at least this big before they're mmap()d. This is to deal
* with systems where the expense of doing an mmap() and an munmap() outweighs
* the benefit for small files. It shouldn't be set lower than 1.
*/
#ifdef MMAP_THRESHOLD
# define APR_MMAP_THRESHOLD MMAP_THRESHOLD
#else
# ifdef SUNOS4
# define APR_MMAP_THRESHOLD (8*1024)
# else
# define APR_MMAP_THRESHOLD 1
# endif /* SUNOS4 */
#endif /* MMAP_THRESHOLD */
#ifdef MMAP_LIMIT
# define APR_MMAP_LIMIT MMAP_LIMIT
#else
# define APR_MMAP_LIMIT (4*1024*1024)
#endif /* MMAP_LIMIT */
#define APR_MMAP_CANDIDATE(filelength) \
((filelength >= APR_MMAP_THRESHOLD) && (filelength < APR_MMAP_LIMIT))
/* Function definitions */
/**
* Create a new mmap'ed file out of an existing APR file.
* @param newmmap The newly created mmap'ed file.
* @param file The file turn into an mmap.
* @param offset The offset into the file to start the data pointer at.
* @param size The size of the file
* @param flag bit-wise or of:
*
* APR_MMAP_READ MMap opened for reading
* APR_MMAP_WRITE MMap opened for writing
*
* @param cntxt The pool to use when creating the mmap.
*/
APR_DECLARE(apr_status_t) apr_mmap_create(apr_mmap_t **newmmap,
apr_file_t *file, apr_off_t offset,
apr_size_t size, apr_int32_t flag,
apr_pool_t *cntxt);
/**
* Duplicate the specified MMAP.
* @param new_mmap The structure to duplicate into.
* @param old_mmap The file to duplicate.
* @param p The pool to use for the new file.
* @param transfer_ownership Whether responsibility for destroying
* the memory-mapped segment is transferred from old_mmap to new_mmap
*/
APR_DECLARE(apr_status_t) apr_mmap_dup(apr_mmap_t **new_mmap,
apr_mmap_t *old_mmap,
apr_pool_t *p,
int transfer_ownership);
/**
* Remove a mmap'ed.
* @param mmap The mmap'ed file.
*/
APR_DECLARE(apr_status_t) apr_mmap_delete(apr_mmap_t *mmap);
/**
* Move the pointer into the mmap'ed file to the specified offset.
* @param addr The pointer to the offset specified.
* @param mmap The mmap'ed file.
* @param offset The offset to move to.
*/
APR_DECLARE(apr_status_t) apr_mmap_offset(void **addr, apr_mmap_t *mmap,
apr_off_t offset);
#endif /* APR_HAS_MMAP */
/** @} */
#ifdef __cplusplus
}
#endif
#endif /* ! APR_MMAP_H */