robin.thoni/ipxe - git rthoni.com

Michael Brown dc8eb04647 [pxe] Treat PXENV_RESTART_TFTP as unreturnable Microsoft WDS can end up calling PXENV_RESTART_TFTP to execute a second-stage NBP which then exits. Specifically, wdsnbp.com uses PXENV_RESTART_TFTP to execute pxeboot.com, which will exit if the user does not press F12. iPXE currently treats PXENV_RESTART_TFTP as a normal PXE API call, and so attempts to return to wdsnbp.com, which has just been vaporised by pxeboot.com. Use rmsetjmp/rmlongjmp to preserve the stack state as of the initial NBP execution, and to restore this state immediately prior to executing the NBP loaded via PXENV_RESTART_TFTP. This matches the behaviour in the PXE spec (which says that "if TFTP is restarted, control is never returned to the caller"), and allows pxeboot.com to exit relatively cleanly back to iPXE. As with all usage of setjmp/longjmp, there may be subtle corner case bugs due to not gracefully unwinding any state accumulated by the time of the longjmp call, but this seems to be the only viable way to provide the specified behaviour. Signed-off-by: Michael Brown <mcb30@ipxe.org>		15 years ago
contrib	[build] Rename gPXE to iPXE	15 years ago
src	[pxe] Treat PXENV_RESTART_TFTP as unreturnable	15 years ago
COPYING	Initial revision	20 years ago
COPYRIGHTS	[build] Rename gPXE to iPXE	15 years ago
README	[build] Rename gPXE to iPXE	15 years ago

iPXE README File

Quick start guide:

   cd src
   make

For any more detailed instructions, see http://ipxe.org