Remove the name, cmdline, and action parameters from imgdownload() and
imgdownload_string().  These functions now simply download and return
an image.

Add the function imgacquire(), which will interpret a "name or URI
string" parameter and return either an existing image or a newly
downloaded image.

Use imgacquire() to merge similar image-management commands that
currently differ only by whether they take the name of an existing
image or the URI of a new image to download.  For example, "chain" and
"imgexec" can now be merged.

Extend imgstat and imgfree commands to take an optional list of
images.

Remove the arbitrary restriction on the length of image names.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

Trusted images may always be executed.  Untrusted images may be
executed only if the current image trust requirement allows untrusted
images.

Images can be marked as trusted using image_trust(), and marked as
untrusted using image_untrust().

The current image trust requirement can be changed using
image_set_trust().  It is possible to make the change permanent, in
which case any future attempts to change the image trust requirement
will fail.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

All users of imgdownload() require registration of the image, so make
registration an integral part of imgdownload() itself and simplify the
"action" parameter to be one of image_select(), image_exec() et al.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

Signed-off-by: Michael Brown <mcb30@ipxe.org>

Allow imgdownload() to be called without first having to allocate (and
so keep track of) an image.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

Signed-off-by: Michael Brown <mcb30@ipxe.org>

These functions are used only as the "action" parameters to
imgdownload() or imgfetch(), and so belong in imgmgmt.c rather than
image.c

Signed-off-by: Michael Brown <mcb30@ipxe.org>

Signed-off-by: Michael Brown <mcb30@ipxe.org>

Refactor the {load,exec} image operations as {probe,exec}.  This makes
the probe mechanism cleaner, eliminates some forward declarations,
avoids holding magic state in image->priv, eliminates the possibility
of screwing up between the "load" and "exec" stages, and makes the
documentation simpler since the concept of "loading" (as distinct from
"executing") no longer needs to be explained.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

image_set_cmdline() strdup()s cmdline, which free_image() doesn't
clean up.

Signed-off-by: Piotr Jaroszyński <p.jaroszynski@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@gmail.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>

Standardise on using ref_init() to initialise an embedded reference
count, to match the coding style used by other embedded objects.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

Access to the gpxe.org and etherboot.org domains and associated
resources has been revoked by the registrant of the domain.  Work
around this problem by renaming project from gPXE to iPXE, and
updating URLs to match.

Also update README, LOG and COPYRIGHTS to remove obsolete information.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

Add FILE_LICENCE declarations to almost all files that make up the
various standard builds of gPXE.

Intel's C compiler (icc) chokes on the zero-length arrays that we
currently use as part of the mechanism for accessing linker table
entries.  Abstract away the zero-length arrays, to make a port to icc
easier.

Introduce macros such as for_each_table_entry() to simplify the common
case of iterating over all entries in a linker table.

Represent table names as #defined string constants rather than
unquoted literals; this avoids visual confusion between table names
and C variable or type names, and also allows us to force a
compilation error in the event of incorrect table names.

When chaining COMBOOT images, the old images now get freed correctly.

Multi-level menus via COMBOOT rely on the COMBOOT program being able
to exit and invoke a new COMBOOT program (the next menu).  This works,
but rapidly (within about five iterations) runs out of space in gPXE's
internal stack, since each new image is executed in a new function
context.

Fix by allowing tail recursion between images; an image can now
specify a replacement image for itself, and image_exec() will perform
the necessary tail recursion.

Clearing the LOADED flag actually prevents users from doing clever things
such as loading an image, then loading a patch image, then executing the
first image.  (image_exec() checks for IMAGE_LOADED, so this sequence of
operations will fail if the LOADED flag gets cleared.)

This reverts commit 14c080020f.

Loading an image may overwrite part or all of any previously-loaded
images, so we should clear the LOADED flag for all images prior to
attempting to load a new image.

executing any image, not just a script.  (This will enable pxelinux to
use relative URIs, should it wish to.)

Some shuffling around of the image management code; this needs tidying up.

allows us to avoid execution loops without having to hack around the
image registration order.

reflect the fact that they allocate and deallocate user memory (i.e.
things reached through a userptr_t).

took out the contract to eventually call efree() when it called fetch().

Maintain the most recently loaded image at the start of the list, so that
imgautoselect() will pick it.

returns the allocated buffer.

refer to them by name from the command line, or build them into a
multiboot module list.

Use setting image->type to disambiguate between "not my image" and "bad
image"; this avoids relying on specific values of the error code.

for use by malloc().

This breaks the image-loading code (which previously used the heap to
allocate the buffer for downloading the image), but that's not a major
concern since I'm going to tear out all the image formats within the next
couple of days anyway.  Byebye, NBI!  :)