It is useful to format a string into a buffer, with the sizing handled
automatically. Add a function for this.

Signed-off-by: Simon Glass <sjg@chromium.org>

It is useful to be able to copy an abuf, to allow changes while
preserving the original. Add a function for this.

Signed-off-by: Simon Glass <sjg@chromium.org>

This construct appears in various places. Reduce code size by adding a
function for it.

It inits the abuf, then allocates it to the requested size.

Signed-off-by: Simon Glass <sjg@chromium.org>

Add a new initialiser which can accept a constant pointer.

Signed-off-by: Simon Glass <sjg@chromium.org>

Some header files included on the host are moving to use abuf, so adjust
the header-inclusion to bring in size_t correctly.

Signed-off-by: Simon Glass <sjg@chromium.org>

In many cases it is useful to get the address of a buffer, e.g. when
booting from it. Add a function to handle this.

Signed-off-by: Simon Glass <sjg@chromium.org>

Provide a convenience function to increment the size of the abuf.

Signed-off-by: Simon Glass <sjg@chromium.org>

Sphinx expects Return: and not @return to indicate a return value.

find . -name '*.c' -exec \
sed -i 's/^\(\s\)\*\(\s*\)@return\(\s\)/\1*\2Return:\3/' {} \;

find . -name '*.h' -exec \
sed -i 's/^\(\s\)\*\(\s*\)@return\(\s\)/\1*\2Return:\3/' {} \;

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>

When passing a data buffer back from a function, it is not always clear
who owns the buffer, i.e. who is responsible for freeing the memory used.
An example of this is where multiple files are decompressed from the
firmware image, using a temporary buffer for reading (since the
compressed data has to live somewhere) and producing a temporary or
permanent buffer with the resuilts.

Where the firmware image can be memory-mapped, as on x86, the compressed
data does not need to be buffered, but the complexity of having a buffer
which is either allocated or not, makes the code hard to understand.

Introduce a new 'abuf' which supports simple buffer operations:

- encapsulating a buffer and its size
- either allocated with malloc() or not
- able to be reliably freed if necessary
- able to be converted to an allocated buffer if needed

This simple API makes it easier to deal with allocated and memory-mapped
buffers.

Signed-off-by: Simon Glass <sjg@chromium.org>