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| -rw-r--r-- | include/apr_mmap.h | 171 |
1 files changed, 171 insertions, 0 deletions
diff --git a/include/apr_mmap.h b/include/apr_mmap.h new file mode 100644 index 0000000..c14de19 --- /dev/null +++ b/include/apr_mmap.h @@ -0,0 +1,171 @@ +/* Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#ifndef APR_MMAP_H +#define APR_MMAP_H + +/** + * @file apr_mmap.h + * @brief APR MMAP routines + */ + +#include "apr.h" +#include "apr_pools.h" +#include "apr_errno.h" +#include "apr_ring.h" +#include "apr_file_io.h" /* for apr_file_t */ + +#ifdef BEOS +#include <kernel/OS.h> +#endif + +#ifdef __cplusplus +extern "C" { +#endif /* __cplusplus */ + +/** + * @defgroup apr_mmap MMAP (Memory Map) Routines + * @ingroup APR + * @{ + */ + +/** MMap opened for reading */ +#define APR_MMAP_READ 1 +/** MMap opened for writing */ +#define APR_MMAP_WRITE 2 + +/** @see apr_mmap_t */ +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; + /** ring of apr_mmap_t's that reference the same + * mmap'ed region; acts in place of a reference count */ + APR_RING_ENTRY(apr_mmap_t) link; +}; + +#if APR_HAS_MMAP || defined(DOXYGEN) + +/** @def APR_MMAP_THRESHOLD + * 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 */ + +/** @def APR_MMAP_LIMIT + * Maximum size of MMap region + */ +#ifdef MMAP_LIMIT +# define APR_MMAP_LIMIT MMAP_LIMIT +#else +# define APR_MMAP_LIMIT (4*1024*1024) +#endif /* MMAP_LIMIT */ + +/** Can this file be MMaped */ +#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 to 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: + * <PRE> + * APR_MMAP_READ MMap opened for reading + * APR_MMAP_WRITE MMap opened for writing + * </PRE> + * @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 mmap to duplicate. + * @param p The pool to use for new_mmap. + */ +APR_DECLARE(apr_status_t) apr_mmap_dup(apr_mmap_t **new_mmap, + apr_mmap_t *old_mmap, + apr_pool_t *p); + +/** + * Remove a mmap'ed. + * @param mm The mmap'ed file. + */ +APR_DECLARE(apr_status_t) apr_mmap_delete(apr_mmap_t *mm); + +/** + * Move the pointer into the mmap'ed file to the specified offset. + * @param addr The pointer to the offset specified. + * @param mm The mmap'ed file. + * @param offset The offset to move to. + */ +APR_DECLARE(apr_status_t) apr_mmap_offset(void **addr, apr_mmap_t *mm, + apr_off_t offset); + +#endif /* APR_HAS_MMAP */ + +/** @} */ + +#ifdef __cplusplus +} +#endif + +#endif /* ! APR_MMAP_H */ |