mirror of
https://github.com/cc65/cc65.git
synced 2025-03-19 22:34:04 +00:00
Added check/support for simple addressing format.
Check the operating system option and return the module id to the caller. Use bzero instead of memset. git-svn-id: svn://svn.cc65.org/cc65/trunk@1278 b7a2c559-68d2-44c3-8de9-860c34a00d81
This commit is contained in:
parent
009df2d6b5
commit
9364b206ab
@ -37,7 +37,7 @@
|
||||
.include "modload.inc"
|
||||
|
||||
.import pushax, pusha0, push0, push1, decax1
|
||||
.import _malloc, _free, _memset
|
||||
.import _malloc, _free, _bzero
|
||||
.import __ZP_START__ ; Linker generated
|
||||
.importzp sp, ptr1, tmp1, regbank
|
||||
|
||||
@ -68,21 +68,16 @@ Header: .res O65_HDR_SIZE ; The o65 header
|
||||
; Input
|
||||
InputByte = Header ; Byte read from input
|
||||
|
||||
; Segment addresses. Since the ld65 linker uses a relocation base address
|
||||
; of zero for all segments, the addresses of the segments are also the
|
||||
; relocation values.
|
||||
CodeAddr = Module ; Address of code seg
|
||||
DataAddr = Header + 1 ; Address of data seg
|
||||
BssAddr = Header + 3 ; Address of bss seg
|
||||
|
||||
.data
|
||||
Read: jmp $FFFF ; Jump to read routine
|
||||
Read: jmp $FFFF ; Jump to read routine
|
||||
|
||||
.rodata
|
||||
ExpectedHdr: .byte $01, $00 ; non C64 marker
|
||||
.byte $6F, $36, $35 ; Magic ("o65")
|
||||
.byte $00 ; Version
|
||||
.word $0000 ; Mode word
|
||||
ExpectedHdr:
|
||||
.byte $01, $00 ; non C64 marker
|
||||
.byte $6F, $36, $35 ; Magic ("o65")
|
||||
.byte $00 ; Version
|
||||
.word O65_CPU_6502|O65_RELOC_BYTE|O65_SIZE_16BIT|O65_FTYPE_EXE|O65_ADDR_SIMPLE|O65_ALIGN_1
|
||||
|
||||
ExpectedHdrSize = * - ExpectedHdr
|
||||
|
||||
|
||||
@ -109,37 +104,33 @@ RestoreRegBank:
|
||||
rts
|
||||
|
||||
;------------------------------------------------------------------------------
|
||||
; GetReloc: Return a relocation value based on the segment in A
|
||||
; GetReloc: Return a relocation value based on the segment in A.
|
||||
; The routine uses some knowledge about the values to make the code shorter.
|
||||
|
||||
.code
|
||||
GetReloc:
|
||||
cmp #O65_SEGID_TEXT
|
||||
bne @L1
|
||||
lda CodeAddr
|
||||
ldx CodeAddr+1
|
||||
bcc FormatError
|
||||
cmp #O65_SEGID_ZP
|
||||
beq @L1
|
||||
bcs FormatError
|
||||
|
||||
; Text, data and bss segment
|
||||
|
||||
lda Module
|
||||
ldx Module+1 ; Return start address of buffer
|
||||
rts
|
||||
|
||||
@L1: cmp #O65_SEGID_DATA
|
||||
bne @L2
|
||||
lda DataAddr
|
||||
ldx DataAddr+1
|
||||
rts
|
||||
; Zero page relocation
|
||||
|
||||
@L2: cmp #O65_SEGID_BSS
|
||||
bne @L3
|
||||
lda BssAddr
|
||||
ldx BssAddr+1
|
||||
rts
|
||||
|
||||
@L3: cmp #O65_SEGID_ZP
|
||||
bne FormatError
|
||||
lda #<__ZP_START__
|
||||
@L1: lda #<__ZP_START__
|
||||
ldx #>__ZP_START__
|
||||
rts
|
||||
|
||||
;------------------------------------------------------------------------------
|
||||
; FormatError: Bail out with an o65 format error
|
||||
|
||||
|
||||
.code
|
||||
FormatError:
|
||||
lda #MLOAD_ERR_FMT
|
||||
; bne CleanupAndExit ; Branch always
|
||||
@ -271,10 +262,8 @@ Loop: jsr ReadByte ; Read byte from relocation table
|
||||
RelocLow:
|
||||
ldy #0
|
||||
clc
|
||||
lda (TPtr),y
|
||||
adc ptr1
|
||||
sta (TPtr),y
|
||||
jmp Loop
|
||||
lda ptr1
|
||||
bcc AddCommon
|
||||
|
||||
; Relocate a high byte
|
||||
|
||||
@ -283,8 +272,10 @@ RelocHigh:
|
||||
ldy #0
|
||||
clc
|
||||
adc ptr1 ; We just need the carry
|
||||
AddHigh:lda (TPtr),y
|
||||
adc ptr1+1
|
||||
AddHigh:
|
||||
lda ptr1+1
|
||||
AddCommon:
|
||||
adc (TPtr),y
|
||||
sta (TPtr),y
|
||||
jmp Loop ; Done, next entry
|
||||
|
||||
@ -293,8 +284,8 @@ AddHigh:lda (TPtr),y
|
||||
RelocWord:
|
||||
ldy #0
|
||||
clc
|
||||
lda (TPtr),y
|
||||
adc ptr1
|
||||
lda ptr1
|
||||
adc (TPtr),y
|
||||
sta (TPtr),y
|
||||
iny
|
||||
bne AddHigh ; Branch always (add high byte)
|
||||
@ -334,7 +325,7 @@ _mod_load:
|
||||
lda (Ctrl),y
|
||||
sta Read+1
|
||||
iny
|
||||
lda (Ctrl),y
|
||||
lda (Ctrl),y
|
||||
sta Read+2
|
||||
|
||||
; Read the o65 header: C->read (C, &H, sizeof (H))
|
||||
@ -350,31 +341,89 @@ _mod_load:
|
||||
; We read the o65 header successfully. Validate it.
|
||||
|
||||
ldy #ExpectedHdrSize-1
|
||||
@L3: lda Header,y
|
||||
ValidateHeader:
|
||||
lda Header,y
|
||||
cmp ExpectedHdr,y
|
||||
beq @L4
|
||||
lda #MLOAD_ERR_HDR
|
||||
jmp CleanupAndExit
|
||||
@L4: dey
|
||||
bpl @L3
|
||||
bne HeaderError
|
||||
dey
|
||||
bpl ValidateHeader
|
||||
|
||||
; Header is ok as far as we can say now. Read and skip all options. We may
|
||||
; add a check here for the OS option later.
|
||||
; Header is ok as far as we can say now. Read all options, check for the
|
||||
; OS option and ignore all others. The OS option contains a version number
|
||||
; and the module id as additional data.
|
||||
|
||||
Opt: jsr ReadByte
|
||||
iny ; Y = $00
|
||||
sty TPtr+1 ; Flag for OS option read
|
||||
Opt: jsr ReadByte ; Read the length byte
|
||||
beq OptDone ; Jump if done
|
||||
sta TPtr ; Use TPtr as a counter
|
||||
OneOpt: dec TPtr
|
||||
|
||||
; An option has a length of at least 2 bytes
|
||||
|
||||
cmp #2
|
||||
bcc HeaderError ; Must be 2 bytes total at least
|
||||
|
||||
; Check for the OS option
|
||||
|
||||
dec TPtr
|
||||
jsr ReadByte ; Get the option type
|
||||
cmp #O65_OPT_OS ; OS option?
|
||||
bne SkipOpt ; No: Skip
|
||||
|
||||
lda TPtr ; Get remaining length+1
|
||||
cmp #5 ; CC65 has 6 bytes total
|
||||
bne OSError
|
||||
|
||||
jsr ReadByte ; Get the operating system
|
||||
cmp #O65_OS_CC65_MODULE
|
||||
bne OSError ; Wrong operating system
|
||||
|
||||
jsr ReadByte ; Get the version number, expect zero
|
||||
bne OSError ; Wrong version
|
||||
|
||||
jsr ReadByte ; Get low byte of id
|
||||
ldy #MODCTRL_MODULE_ID
|
||||
sta (Ctrl),y
|
||||
jsr ReadByte
|
||||
ldy #MODCTRL_MODULE_ID+1
|
||||
sta (Ctrl),y
|
||||
|
||||
inc TPtr+1 ; Remember that we got the OS
|
||||
|
||||
jmp Opt
|
||||
|
||||
; Skip one option
|
||||
|
||||
SkipOpt:
|
||||
dec TPtr
|
||||
beq Opt ; Next option
|
||||
jsr ReadByte ; Skip one byte
|
||||
jmp OneOpt
|
||||
jmp SkipOpt
|
||||
|
||||
; Operating system error
|
||||
|
||||
OSError:
|
||||
lda #MLOAD_ERR_OS
|
||||
jmp CleanupAndExit
|
||||
|
||||
; Options done, check that we got the OS option
|
||||
|
||||
OptDone:
|
||||
lda TPtr+1
|
||||
bne CalcSizes
|
||||
|
||||
; Entry point for header errors
|
||||
|
||||
HeaderError:
|
||||
lda #MLOAD_ERR_HDR
|
||||
jmp CleanupAndExit
|
||||
|
||||
; Skipped all options. Calculate the size of text+data and of text+data+bss
|
||||
; (the latter is the size of the memory block we need). We will store the
|
||||
; total module size also into the control structure for evaluation by the
|
||||
; caller
|
||||
|
||||
CalcSizes:
|
||||
lda Header + O65_HDR_TLEN
|
||||
add Header + O65_HDR_DLEN
|
||||
sta TPtr
|
||||
@ -393,12 +442,20 @@ OptDone:
|
||||
tax
|
||||
pla ; Restore low byte of total size
|
||||
|
||||
; Total memory size is now in a/x. Allocate memory, check if we got it.
|
||||
; Total memory size is now in a/x. Allocate memory and remember the result,
|
||||
; both, locally and in the control structure so it the caller can access
|
||||
; the memory block. After that, check if we got the requested memory.
|
||||
|
||||
jsr _malloc
|
||||
sta Module
|
||||
stx Module+1
|
||||
ora Module+1
|
||||
|
||||
ldy #MODCTRL_MODULE
|
||||
sta (Ctrl),y
|
||||
txa
|
||||
iny
|
||||
sta (Ctrl),y
|
||||
ora Module
|
||||
bne GotMem
|
||||
|
||||
; Could not allocate memory
|
||||
@ -406,39 +463,26 @@ OptDone:
|
||||
lda #MLOAD_ERR_MEM
|
||||
jmp CleanupAndExit
|
||||
|
||||
; We got the memory block. Place a pointer to the memory block also in the
|
||||
; module control structure.
|
||||
|
||||
GotMem: lda Module ; Ctrl->module = Module;
|
||||
ldy #MODCTRL_MODULE
|
||||
sta (Ctrl),y
|
||||
txa
|
||||
iny
|
||||
sta (Ctrl),y
|
||||
|
||||
; Calculate the start addresses of the segments. Since the linker uses a
|
||||
; base address of zero for all segments, the load addresses are also the
|
||||
; relocation values for the segments.
|
||||
|
||||
lda Module
|
||||
add Header + O65_HDR_TLEN
|
||||
sta DataAddr
|
||||
lda Module + 1
|
||||
adc Header + O65_HDR_TLEN + 1
|
||||
sta DataAddr + 1
|
||||
; Control structure is complete now. Clear the bss segment.
|
||||
; bzero (bss_addr, bss_size)
|
||||
|
||||
lda Module
|
||||
add TPtr
|
||||
sta BssAddr
|
||||
pha
|
||||
lda Module+1
|
||||
add TPtr+1
|
||||
sta BssAddr + 1
|
||||
adc TPtr+1 ; Module + tlen + dlen
|
||||
tax
|
||||
pla
|
||||
jsr pushax
|
||||
lda Header + O65_HDR_BLEN
|
||||
ldx Header + O65_HDR_BLEN+1
|
||||
jsr _bzero ; bzero (bss, bss_size);
|
||||
|
||||
; Control structure is complete now. Load code and data segment into memory.
|
||||
; The sum of the sizes of code+data segment is still in TPtr.
|
||||
; Load code and data segment into memory. The sum of the sizes of
|
||||
; code+data segment is still in TPtr.
|
||||
; C->read (C, C->module, H.tlen + H.dlen)
|
||||
|
||||
jsr PushCtrl
|
||||
GotMem: jsr PushCtrl
|
||||
lda Module
|
||||
ldx Module+1
|
||||
jsr pushax
|
||||
@ -472,19 +516,9 @@ Reloc: lda Module
|
||||
lda Module + 1
|
||||
adc Header + O65_HDR_TLEN + 1
|
||||
tax
|
||||
pla ; Date segment address in a/x
|
||||
pla ; Data segment address in a/x
|
||||
jsr RelocSeg
|
||||
|
||||
; Clear the bss segment: memset (bss_addr, 0, bss_size)
|
||||
|
||||
lda BssAddr
|
||||
ldx BssAddr + 1
|
||||
jsr pushax
|
||||
jsr push0
|
||||
lda Header + O65_HDR_BLEN
|
||||
ldx Header + O65_HDR_BLEN+1
|
||||
jsr _memset ; memset (bss, 0, bss_size);
|
||||
|
||||
; We're done. Restore the register bank and return a success code
|
||||
|
||||
jsr RestoreRegBank ; X will be zero on return
|
||||
|
Loading…
x
Reference in New Issue
Block a user