[41] | 1 | ; Project name : Assembly Library |
---|
| 2 | ; Description : Functions for size calculations. |
---|
| 3 | |
---|
[85] | 4 | struc BYTE_MULTIPLES |
---|
| 5 | .B resb 1 |
---|
| 6 | .kiB resb 1 |
---|
| 7 | .MiB resb 1 |
---|
| 8 | .GiB resb 1 |
---|
| 9 | .TiB resb 1 |
---|
| 10 | endstruc |
---|
| 11 | |
---|
[41] | 12 | ; Section containing code |
---|
| 13 | SECTION .text |
---|
| 14 | |
---|
| 15 | ;-------------------------------------------------------------------- |
---|
[85] | 16 | ; Size_GetSizeToAXAndCharToDLfromBXDXAXwithMagnitudeInCX |
---|
[41] | 17 | ; Parameters: |
---|
| 18 | ; BX:DX:AX: Size in magnitude |
---|
[85] | 19 | ; CX: Magnitude in BYTE_MULTIPLES |
---|
[41] | 20 | ; Returns: |
---|
| 21 | ; AX: Size in magnitude |
---|
| 22 | ; CX: Tenths |
---|
| 23 | ; DL: Magnitude character: |
---|
| 24 | ; 'k' = *1024 B = kiB |
---|
| 25 | ; 'M' = *1024 kiB = MiB |
---|
| 26 | ; 'G' = *1024 MiB = GiB |
---|
| 27 | ; 'T' = *1024 GiB = TiB |
---|
| 28 | ; 'P' = *1024 TiB = PiB |
---|
| 29 | ; Corrupts registers: |
---|
| 30 | ; BX, DH |
---|
| 31 | ;-------------------------------------------------------------------- |
---|
[369] | 32 | ALIGN UTIL_SIZE_JUMP_ALIGN |
---|
[41] | 33 | Size_GetSizeToAXAndCharToDLfromBXDXAXwithMagnitudeInCX: |
---|
[142] | 34 | %ifndef USE_186 ; If 8086/8088 |
---|
| 35 | push di |
---|
| 36 | %endif |
---|
[41] | 37 | push si |
---|
| 38 | |
---|
[369] | 39 | ALIGN UTIL_SIZE_JUMP_ALIGN |
---|
[41] | 40 | .MagnitudeConversionLoop: |
---|
[142] | 41 | ePUSH_T di, .MagnitudeConversionLoop; DI corrupted only on 8086/8088 build |
---|
| 42 | test bx, bx ; Bits 32...47 in use? |
---|
[41] | 43 | jnz SHORT Size_DivideSizeInBXDXAXby1024andIncrementMagnitudeInCX |
---|
[142] | 44 | test dx, dx ; Bits 16...31 in use? |
---|
[41] | 45 | jnz SHORT Size_DivideSizeInBXDXAXby1024andIncrementMagnitudeInCX |
---|
[142] | 46 | cmp ax, 10000 ; 5 digits needed? |
---|
[41] | 47 | jae SHORT Size_DivideSizeInBXDXAXby1024andIncrementMagnitudeInCX |
---|
[142] | 48 | add sp, BYTE 2 ; Clean return address from stack |
---|
| 49 | xchg si, cx ; CX = Remainder (0...1023), SI = Magnitude |
---|
[41] | 50 | |
---|
[141] | 51 | ; Convert remainder to tenths |
---|
[142] | 52 | xchg bx, ax ; Store AX |
---|
[141] | 53 | mov ax, 10 |
---|
[142] | 54 | mul cx ; DX:AX = remainder * 10 |
---|
| 55 | eSHR_IM ax, 10 ; Divide AX by 1024 |
---|
| 56 | xchg cx, ax ; CX = tenths |
---|
[141] | 57 | xchg ax, bx |
---|
| 58 | |
---|
| 59 | ; Convert magnitude to character |
---|
| 60 | mov dl, [cs:si+.rgbMagnitudeToChar] |
---|
| 61 | |
---|
[41] | 62 | pop si |
---|
[142] | 63 | %ifndef USE_186 |
---|
| 64 | pop di |
---|
| 65 | %endif |
---|
[41] | 66 | ret |
---|
[141] | 67 | .rgbMagnitudeToChar: db " kMGTP" |
---|
[41] | 68 | |
---|
[141] | 69 | |
---|
[41] | 70 | ;-------------------------------------------------------------------- |
---|
| 71 | ; Size_DivideSizeInBXDXAXby1024andIncrementMagnitudeInCX |
---|
| 72 | ; Parameters: |
---|
| 73 | ; BX:DX:AX: Size |
---|
[85] | 74 | ; CX: Magnitude in BYTE_MULTIPLES |
---|
[41] | 75 | ; Returns: |
---|
| 76 | ; BX:DX:AX: Size in magnitude |
---|
| 77 | ; SI: Remainder (0...1023) |
---|
[85] | 78 | ; CX: Magnitude in BYTE_MULTIPLES |
---|
[41] | 79 | ; Corrupts registers: |
---|
| 80 | ; Nothing |
---|
| 81 | ;-------------------------------------------------------------------- |
---|
[369] | 82 | ALIGN UTIL_SIZE_JUMP_ALIGN |
---|
[41] | 83 | Size_DivideSizeInBXDXAXby1024andIncrementMagnitudeInCX: |
---|
| 84 | push cx |
---|
| 85 | xor si, si ; Zero remainder |
---|
| 86 | mov cl, 10 ; Divide by 1024 |
---|
[369] | 87 | ALIGN UTIL_SIZE_JUMP_ALIGN |
---|
[41] | 88 | .ShiftLoop: |
---|
| 89 | call Size_DivideBXDXAXbyTwo |
---|
| 90 | rcr si, 1 ; Update remainder |
---|
| 91 | loop .ShiftLoop |
---|
| 92 | eSHR_IM si, 6 ; Remainder to SI beginning |
---|
| 93 | pop cx |
---|
| 94 | inc cx ; Increment magnitude |
---|
| 95 | ret |
---|
| 96 | |
---|
| 97 | |
---|
| 98 | ;-------------------------------------------------------------------- |
---|
| 99 | ; Size_ConvertSectorCountInBXDXAXtoKiB |
---|
| 100 | ; Size_DivideBXDXAXbyTwo |
---|
| 101 | ; Parameters: |
---|
| 102 | ; BX:DX:AX: Total sector count |
---|
| 103 | ; Returns: |
---|
| 104 | ; BX:DX:AX: Total size in kiB |
---|
| 105 | ; CF: Remainder from division |
---|
| 106 | ; Corrupts registers: |
---|
| 107 | ; Nothing |
---|
| 108 | ;-------------------------------------------------------------------- |
---|
[369] | 109 | ALIGN UTIL_SIZE_JUMP_ALIGN |
---|
[41] | 110 | Size_ConvertSectorCountInBXDXAXtoKiB: |
---|
| 111 | Size_DivideBXDXAXbyTwo: |
---|
| 112 | shr bx, 1 ; Divide sector count by 2... |
---|
| 113 | rcr dx, 1 ; ...to get disk size in... |
---|
| 114 | rcr ax, 1 ; ...kiB |
---|
| 115 | ret |
---|