mirror of
https://github.com/HDFGroup/hdf5.git
synced 2024-11-27 02:10:55 +08:00
73 lines
2.5 KiB
Plaintext
73 lines
2.5 KiB
Plaintext
|
HEAP MANAGEMENT IN HDF5
|
||
|
|
------------------------
|
||
|
|
|
||
|
|
Heap functions are in the H5H package.
|
||
|
|
|
||
|
|
|
||
|
|
off_t
|
||
|
|
H5H_new (hdf5_file_t *f, size_t size_hint, size_t realloc_hint);
|
||
|
|
|
||
|
|
Creates a new heap in the specified file which can efficiently
|
||
|
|
store at least SIZE_HINT bytes. The heap can store more than
|
||
|
|
that, but doing so may cause the heap to become less efficient
|
||
|
|
(for instance, a heap implemented as a B-tree might become
|
||
|
|
discontigous). The REALLOC_HINT is the minimum number of bytes
|
||
|
|
by which the heap will grow when it must be resized. The hints
|
||
|
|
may be zero in which case reasonable (but probably not
|
||
|
|
optimal) values will be chosen.
|
||
|
|
|
||
|
|
The return value is the address of the new heap relative to
|
||
|
|
the beginning of the file boot block.
|
||
|
|
|
||
|
|
off_t
|
||
|
|
H5H_insert (hdf5_file_t *f, off_t addr, size_t size, const void *buf);
|
||
|
|
|
||
|
|
Copies SIZE bytes of data from BUF into the heap whose address
|
||
|
|
is ADDR in file F. BUF must be the _entire_ heap object. The
|
||
|
|
return value is the byte offset of the new data in the heap.
|
||
|
|
|
||
|
|
void *
|
||
|
|
H5H_read (hdf5_file_t *f, off_t addr, off_t offset, size_t size, void *buf);
|
||
|
|
|
||
|
|
Copies SIZE bytes of data from the heap whose address is ADDR
|
||
|
|
in file F into BUF and then returns the address of BUF. If
|
||
|
|
BUF is the null pointer then a new buffer will be malloc'd by
|
||
|
|
this function and its address is returned.
|
||
|
|
|
||
|
|
Returns buffer address or null.
|
||
|
|
|
||
|
|
const void *
|
||
|
|
H5H_peek (hdf5_file_t *f, off_t addr, off_t offset)
|
||
|
|
|
||
|
|
A more efficient version of H5H_read that returns a pointer
|
||
|
|
directly into the cache; the data is not copied from the cache
|
||
|
|
to a buffer. The pointer is valid until the next call to an
|
||
|
|
H5AC function directly or indirectly.
|
||
|
|
|
||
|
|
Returns a pointer or null. Do not free the pointer.
|
||
|
|
|
||
|
|
void *
|
||
|
|
H5H_write (hdf5_file_t *f, off_t addr, off_t offset, size_t size,
|
||
|
|
const void *buf);
|
||
|
|
|
||
|
|
Modifies (part of) an object in the heap at address ADDR of
|
||
|
|
file F by copying SIZE bytes from the beginning of BUF to the
|
||
|
|
file. OFFSET is the address withing the heap where the output
|
||
|
|
is to occur.
|
||
|
|
|
||
|
|
This function can fail if the combination of OFFSET and SIZE
|
||
|
|
would write over a boundary between two heap objects.
|
||
|
|
|
||
|
|
herr_t
|
||
|
|
H5H_remove (hdf5_file_t *f, off_t addr, off_t offset, size_t size);
|
||
|
|
|
||
|
|
Removes an object or part of an object which begins at byte
|
||
|
|
OFFSET within a heap whose address is ADDR in file F. SIZE
|
||
|
|
bytes are returned to the free list. Removing the middle of
|
||
|
|
an object has the side effect that one object is now split
|
||
|
|
into two objects.
|
||
|
|
|
||
|
|
Returns success or failure.
|
||
|
|
|
||
|
|
|