aboutsummaryrefslogtreecommitdiffstats
path: root/ui.inc
blob: c2c9e83f9c172acbb49e0c9e1e93a5a46d11fcbb (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
;; $Id$
;; -----------------------------------------------------------------------
;;   
;;   Copyright 1994-2002 H. Peter Anvin - All Rights Reserved
;;
;;   This program is free software; you can redistribute it and/or modify
;;   it under the terms of the GNU General Public License as published by
;;   the Free Software Foundation, Inc., 53 Temple Place Ste 330,
;;   Boston MA 02111-1307, USA; either version 2 of the License, or
;;   (at your option) any later version; incorporated herein by reference.
;;
;; -----------------------------------------------------------------------

;
; This file should be entered with the config file open (for getc)
;
		call parse_config		; Parse configuration file
no_config_file:
;
; Check whether or not we are supposed to display the boot prompt.
;
check_for_key:
		cmp word [ForcePrompt],0	; Force prompt?
		jnz enter_command
		test byte [KbdFlags],5Bh	; Shift Alt Caps Scroll
		jz auto_boot			; If neither, default boot

enter_command:
		cmp word [NoEscape],0		; If NOESCAPE, no prompt,
		jne auto_boot			; always run default cmd

		mov si,boot_prompt
		call cwritestr

		mov byte [FuncFlag],0		; <Ctrl-F> not pressed
		mov di,command_line

;
; get the very first character -- we can either time
; out, or receive a character press at this time.  Some dorky BIOSes stuff
; a return in the buffer on bootup, so wipe the keyboard buffer first.
;
clear_buffer:	mov ah,11h			; Check for pending char
		int 16h
		jz get_char_time
		mov ah,10h			; Get char
		int 16h
		jmp short clear_buffer

		; For the first character, both KbdTimeout and
		; TotalTimeout apply; after that, only TotalTimeout.

get_char_time:
		mov eax,[TotalTimeout]
		mov [ThisTotalTo],eax
		mov eax,[KbdTimeout]
		mov [ThisKbdTo],eax

get_char:
		call getchar_timeout
		and dword [ThisKbdTo],0		; For the next time...

		and al,al
		jz func_key

got_ascii:	cmp al,7Fh			; <DEL> == <BS>
		je backspace
		cmp al,' '			; ASCII?
		jb not_ascii
		ja enter_char
		cmp di,command_line		; Space must not be first
		je short get_char
enter_char:	test byte [FuncFlag],1
		jz .not_ctrl_f
		mov byte [FuncFlag],0
		cmp al,'0'
		jb .not_ctrl_f
		je ctrl_f_0
		cmp al,'9'
		jbe ctrl_f
.not_ctrl_f:	cmp di,max_cmd_len+command_line ; Check there's space
		jnb short get_char
		stosb				; Save it
		call writechr			; Echo to screen
		jmp short get_char
not_ascii:	mov byte [FuncFlag],0
		cmp al,0Dh			; Enter
		je command_done
		cmp al,'F' & 1Fh		; <Ctrl-F>
		je set_func_flag
		cmp al,'U' & 1Fh		; <Ctrl-U>
		je kill_command			; Kill input line
		cmp al,'V' & 1Fh		; <Ctrl-V>
		je print_version
		cmp al,'X' & 1Fh		; <Ctrl-X>
		je force_text_mode
		cmp al,08h			; Backspace
		jne get_char
backspace:	cmp di,command_line		; Make sure there is anything
		je get_char			; to erase
		dec di				; Unstore one character
		mov si,wipe_char		; and erase it from the screen
		call cwritestr
		jmp short get_char_2

kill_command:
		call crlf
		jmp enter_command

force_text_mode:
		call vgaclearmode
		jmp enter_command

set_func_flag:
		mov byte [FuncFlag],1
get_char_2:
		jmp short get_char

ctrl_f_0:	add al,10			; <Ctrl-F>0 == F10
ctrl_f:		sub al,'1'
		xor ah,ah
		jmp short show_help

func_key:
		; AL = 0 if we get here
		xchg al,ah
		cmp al,68			; F10
		ja short get_char_2
		sub al,59			; F1
		jb short get_char_2
show_help:	; AX = func key # (0 = F1, 9 = F10)
		push di				; Save end-of-cmdline pointer
		shl ax,FILENAME_MAX_LG2		; Convert to pointer
		add ax,FKeyName
		xchg di,ax
		cmp byte [di+NULLOFFSET],NULLFILE
		je short fk_nofile		; Undefined F-key
		call searchdir
		jz short fk_nofile		; File not found
		push si
		call crlf
		pop si
		call get_msg_file
		jmp short fk_wrcmd

print_version:
		push di				; Command line write pointer
		mov si,syslinux_banner
		call cwritestr
%ifdef HAVE_BIOSNAME
		mov si,[BIOSName]
		call cwritestr
%endif
		mov si,copyright_str
		call cwritestr

		; ... fall through ...

		; Write the boot prompt and command line again and
		; wait for input.  Note that this expects the cursor
		; to already have been CRLF'd, and that the old value
		; of DI (the command line write pointer) is on the stack.
fk_wrcmd:
		mov si,boot_prompt
		call cwritestr
		pop di				; Command line write pointer
		push di
		mov byte [di],0			; Null-terminate command line
		mov si,command_line
		call cwritestr			; Write command line so far
fk_nofile:	pop di
		jmp short get_char_2

;
; Jump here to run the default command line
;
auto_boot:
		mov si,default_cmd
		mov di,command_line
		mov cx,(max_cmd_len+4) >> 2
		rep movsd
		jmp short load_kernel

;
; Jump here when the command line is completed
;
command_done:
		call crlf
		cmp di,command_line		; Did we just hit return?
		je auto_boot
		xor al,al			; Store a final null
		stosb

load_kernel:					; Load the kernel now
;
; First we need to mangle the kernel name the way DOS would...
;
		mov si,command_line
                mov di,KernelName
                push si
                push di
		call mangle_name
		pop di
                pop si
;
; Fast-forward to first option (we start over from the beginning, since
; mangle_name doesn't necessarily return a consistent ending state.)
;
clin_non_wsp:   lodsb
                cmp al,' '
                ja clin_non_wsp
clin_is_wsp:    and al,al
                jz clin_opt_ptr
                lodsb
                cmp al,' '
                jbe clin_is_wsp
clin_opt_ptr:   dec si                          ; Point to first nonblank
                mov [CmdOptPtr],si		; Save ptr to first option
;
; If "allowoptions 0", put a null character here in order to ignore any
; user-specified options.
;
		mov ax,[AllowOptions]
		and ax,ax
		jnz clin_opt_ok
		mov [si],al
clin_opt_ok:

;
; Now check if it is a "virtual kernel"
;
vk_check:
		xor si,si			; Beginning of vk_seg
.scan:
		cmp si,[VKernelBytes]
		jae .not_vk

		push ds
		push word vk_seg
		pop ds

		mov di,VKernelBuf
		call rllunpack
		pop ds
		; SI updated on return

		sub di,cx			; Return to beginning of buf
		push si
		mov si,KernelName
		mov cx,FILENAME_MAX
		es repe cmpsb
		pop si
		je .found
		jmp .scan

;
; We *are* using a "virtual kernel"
;
.found:
		push es
		push word real_mode_seg
		pop es
		mov di,cmd_line_here
		mov si,VKernelBuf+vk_append
		mov cx,[VKernelBuf+vk_appendlen]
		rep movsb
		mov [CmdLinePtr],di		; Where to add rest of cmd
		pop es
		mov di,KernelName
		push di	
		mov si,VKernelBuf+vk_rname
		mov cx,FILENAME_MAX		; We need ECX == CX later
		rep movsb
		pop di
%if IS_PXELINUX
		mov al,[VKernelBuf+vk_ipappend]
		mov [IPAppend],al
%endif
		xor bx,bx			; Try only one version

%if IS_PXELINUX || IS_ISOLINUX
		; Is this a "localboot" pseudo-kernel?
%if IS_PXELINUX
		cmp byte [VKernelBuf+vk_rname+4], 0
%else
		cmp byte [VKernelBuf+vk_rname], 0
%endif
		jne get_kernel		; No, it's real, go get it

		mov ax, [VKernelBuf+vk_rname+1]
		jmp local_boot
%else
		jmp get_kernel
%endif

.not_vk:

;
; Not a "virtual kernel" - check that's OK and construct the command line
;
                cmp word [AllowImplicit],byte 0
                je bad_implicit
                push es
                push si
                push di
                mov di,real_mode_seg
                mov es,di
                mov si,AppendBuf
                mov di,cmd_line_here
                mov cx,[AppendLen]
                rep movsb
                mov [CmdLinePtr],di
                pop di
                pop si
                pop es
;
; Find the kernel on disk
;
get_kernel:     mov byte [KernelName+FILENAME_MAX],0	; Zero-terminate filename/extension
%if IS_SYSLINUX || IS_MDSLINUX			; SYSLINUX has to deal with DOS mangled names...
		mov eax,[KernelName+8]		; Save initial extension
		mov [exten_table_end],eax	; Last case == initial ext.
%else
		mov di,KernelName+4*IS_PXELINUX
		xor al,al
		mov cx,FILENAME_MAX-5		; Need 4 chars + null
		repne scasb			; Scan for final null
		jne .no_skip
		dec di				; Point to final null 
.no_skip:	mov [KernelExtPtr],di
%endif
		mov bx,exten_table
.search_loop:	push bx
                mov di,KernelName	      	; Search on disk
                call searchdir
		pop bx
                jnz kernel_good
		mov eax,[bx]			; Try a different extension
%if IS_SYSLINUX || IS_MDSLINUX
		mov [KernelName+8],eax
%else
		mov si,[KernelExtPtr]
		mov [si],eax
		mov byte [si+4],0
%endif
		add bx,byte 4
		cmp bx,exten_table_end
		jna .search_loop		; allow == case (final case)
		; Fall into bad_kernel
;
; bad_kernel: Kernel image not found
; bad_implicit: The user entered a nonvirtual kernel name, with "implicit 0"
;
bad_implicit:
bad_kernel:
		mov cx,[OnerrorLen]
		and cx,cx
		jnz on_error
.really:
		mov si,KernelName
                mov di,KernelCName
		push di
                call unmangle_name              ; Get human form
		mov si,err_notfound		; Complain about missing kernel
		call cwritestr
		pop si				; KernelCName
                call cwritestr
                mov si,crlf_msg
                jmp abort_load                  ; Ask user for clue

;
; on_error: bad kernel, but we have onerror set
;
on_error:
		mov si,Onerror
		mov di,command_line
		push si				; <A>
		push di				; <B>
		push cx				; <C>
		push cx				; <D>
		push di				; <E>
		repe cmpsb
		pop di				; <E> di == command_line
		pop bx				; <D> bx == [OnerrorLen]
		je bad_kernel.really		; Onerror matches command_line already
		neg bx				; bx == -[OnerrorLen]
		lea cx,[max_cmd_len+bx]
		; CX == max_cmd_len-[OnerrorLen]
		mov di,command_line+max_cmd_len-1
		mov byte [di+1],0		; Enforce null-termination
		lea si,[di+bx]
		std
		rep movsb			; Make space in command_line
		cld
		pop cx				; <C> cx == [OnerrorLen]
		pop di				; <B> di == command_line
		pop si				; <A> si  == Onerror
		rep movsb
		jmp load_kernel

;
; kernel_corrupt: Called if the kernel file does not seem healthy
;
kernel_corrupt: mov si,err_notkernel
                jmp abort_load

;
; Get a key, observing ThisKbdTO and ThisTotalTO -- those are timeouts
; which can be adjusted by the caller based on the corresponding
; master variables; on return they're updated.
;
; This cheats.  If we say "no timeout" we actually get a timeout of
; 7.5 years.
;
getchar_timeout:
		call vgashowcursor
		RESET_IDLE

.loop:
		push word [BIOS_timer]
		call pollchar
		jnz .got_char
		pop ax
		cmp ax,[BIOS_timer]		; Has the timer advanced?
		je .loop
		DO_IDLE
		
		dec dword [ThisKbdTo]
		jz .timeout
		dec dword [ThisTotalTo]
		jnz .loop

.timeout:
		; Timeout!!!!
		pop cx				; Discard return address
		call vgahidecursor
		mov si,Ontimeout		; Copy ontimeout command
		mov cx,[OntimeoutLen]		; if we have one...
		rep movsb
		jmp command_done

.got_char:
		pop cx				; Discard
		call getchar
		call vgahidecursor
		ret

;
; This is it!  We have a name (and location on the disk)... let's load
; that sucker!!  First we have to decide what kind of file this is; base
; that decision on the file extension.  The following extensions are
; recognized; case insensitive:
;
; .com 	- COMBOOT image
; .cbt	- COMBOOT image
; .c32  - COM32 image
; .bs	- Boot sector
; .0	- PXE bootstrap program (PXELINUX only)
; .bin  - Boot sector
; .bss	- Boot sector, but transfer over DOS superblock (SYSLINUX only)
; .img  - Floppy image (ISOLINUX only)
;
; Anything else is assumed to be a Linux kernel.
;
		section .bss
		alignb 4
Kernel_EAX	resd 1
Kernel_SI	resw 1

		section .text
kernel_good_saved:
		; Alternate entry point for which the return from
		; searchdir is stored in memory.  This is used for
		; COMBOOT function INT 22h, AX=0016h.
		mov si,[Kernel_SI]
		mov eax,[Kernel_EAX]
		mov dx,[Kernel_EAX+2]

kernel_good:
		pusha
		mov si,KernelName
		mov di,KernelCName
		call unmangle_name
		sub di,KernelCName
		mov [KernelCNameLen],di
		popa
		
%if IS_SYSLINUX || IS_MDSLINUX
		mov ecx,[KernelName+7]
		mov cl,'.'
%else
		push di
		push ax
		mov di,KernelName+4*IS_PXELINUX
		xor al,al
		mov cx,FILENAME_MAX
		repne scasb
		jne .one_step
		dec di
.one_step:	mov ecx,[di-4]			; 4 bytes before end
		pop ax
		pop di
%endif

;
; At this point, DX:AX contains the size of the kernel, and SI contains
; the file handle/cluster pointer.
;
		or ecx,20202000h		; Force lower case

		cmp ecx,'.com'
		je is_comboot_image
		cmp ecx,'.cbt'
		je is_comboot_image
		cmp ecx,'.c32'
		je is_com32_image
%if IS_ISOLINUX
		cmp ecx,'.img'
		je is_disk_image
%endif
		cmp ecx,'.bss'
		je is_bss_sector
		cmp ecx,'.bin'
		je is_bootsector
%if IS_SYSLINUX || IS_MDSLINUX
		cmp ecx,'.bs '
		je is_bootsector
		cmp ecx,'.0  '
		je is_bootsector
%else
		shr ecx,8
		cmp ecx,'.bs'
		je is_bootsector
		shr ecx,8
		cmp cx,'.0'
		je is_bootsector
%endif
		; Otherwise Linux kernel

		section .bss
		alignb 4
ThisKbdTo	resd 1			; Temporary holder for KbdTimeout
ThisTotalTo	resd 1			; Temporary holder for TotalTimeout
KernelExtPtr	resw 1			; During search, final null pointer
CmdOptPtr       resw 1			; Pointer to first option on cmd line
KbdFlags	resb 1			; Check for keyboard escapes
FuncFlag	resb 1			; Escape sequences received from keyboard

		section .text