libk  Check-in [f0f16493ca]

#include <k/core.h>
extern stat entry(kenv);


stat _boot(unsigned int argc, char** argv) {


	kenv e = { 
		// todo: determine terminal class and set term vs ansi correctly!
		{ {kiostream_term, 0}, {kiostream_term, 1} }, // chan std
		{ {kiostream_closed},  {kiostream_term, 2} }, // chan err
		argc, argv,
		null // no environment yet
	};
	return entry(e);
}
	

#include <k/core.h>
extern stat entry(kenv);

unsigned long long
_boot(unsigned int argc, /* argument count */
		char** argv, /* arguments */
		char** envp /* environment */ ) {
	kenv e = { 
		/* TODO: determine terminal class and set term vs ansi correctly! */
		{ {kiostream_term, 0}, {kiostream_term, 1} }, // chan std
		{ {kiostream_closed},  {kiostream_term, 2} }, // chan err
		argc, argv, 
		null // needs parsing
	};
	return entry(e);
}
	

bits 64
%include "../arch/posix/x86.lin.64.s"
global _start:function
extern _boot
extern entry

_start:
	mov rbp, rsp
	mov rdi, [rbp + 0] ; argc

















	lea rsi, [rbp + 8] ; argv





















	call _boot










	mov sys.reg.1, sys.reg.ret


	mov sys.reg.0, sys.exit


	sys.call

bits 64
%include "../arch/posix/x86.lin.64.s"
global _start:function
extern _boot
extern entry

_start:
	mov rbp, 0 ; zero the stack base ptr.
	; attempted fix for a difficult-to-
	; reproduce bug

	mov rdi, 0 ; zero rdi - because argc
	; is 32 bits long, we have to store
	; its value in the lower half of rdi.
	; this ensures that the upper half is
	; zeroed as well.

	mov edi, [rsp + 0] ; sizeof arguments
	; first argument to _boot(): argc
	; this is a 32-bit signed(??) integer
	; that is equal to the number of
	; elements in argv (see below). it is
	; not strictly necessary, because argv
	; is per spec always null-terminated,
	; but we pass it just in case.

	lea rsi, [rsp + 8] ; &arguments
	; 2nd argument to _boot(): ptr to argv
	; this points to an array of strings
	; containing the program's command line
	; arguments. _boot() does not need to 
	; parse this, but it does need to store
	; it in the structure passed to main()

	lea rdx, [rsp + 16] ; &environment
	; third argument to _boot(): ptr to envp
	; this points to the list of environment
	; variables for the running program. it
	; is the responsibility of _boot to parse
	; this list and arrange it into a set of
	; legible and useful C arrays.

	mov rax, 0 ; zero out %rax
	; this is required by the C ABI, and is
	; reputedly necessary for compatibility
	; with icc, intel's own proprietary C
	; compiler.

	call _boot ; invoke the start function
	; that will set up the runtime and
	; construct the necessary structures
	; that will be bassed to libc.

	; boot has returned and left its
	; return value in the register %rax.
	; regardless of the size of the
	; return value of main(), _boot always
	; returns the system word length.

	mov sys.reg.1, sys.reg.ret ; fill in
	; the return value as exit's argument

	mov sys.reg.0, sys.exit ; set %rax to
	; the syscall number of exit

	sys.call ; invoke the kernel