/* ARM assembly Raspberry PI or android with termux */
/*  program filelen.s   */

 /* REMARK 1 : this program use routines in a include file
   see task Include a file language arm assembly
   for the routine affichageMess conversion10
   see at end of this program the instruction include */
/* for constantes see task include a file in arm assembly */
/************************************/
/* Constantes                       */
/************************************/
.include "../constantes.inc"

.equ OPEN,      5
.equ NEWFSTAT,  0xc5

.equ O_RDWR,   0x0002          @ open for reading and writing

/************************************/
/* structure de type   stat  : file infos   */
/************************************/
    .struct  0
Stat_dev_t:               /* ID of device containing file */
    .struct Stat_dev_t + 8
Stat_ino_t:              /* inode */
    .struct Stat_ino_t + 8
Stat_mode_t:              /* File type and mode */
    .struct Stat_mode_t + 4
Stat_nlink_t:               /* Number of hard links */
    .struct Stat_nlink_t + 4
Stat_uid_t:               /* User ID of owner */
    .struct Stat_uid_t + 4
Stat_gid_t:                 /* Group ID of owner */
    .struct Stat_gid_t + 4
Stat_rdev_t:                /* Device ID (if special file) */
    .struct Stat_rdev_t + 8
Stat_size_deb:           /* la taille est sur 8 octets si gros fichiers */
     .struct Stat_size_deb + 8
Stat_size_t:                /* Total size, in bytes */
    .struct Stat_size_t + 4
Stat_blksize_t:                /* Block size for filesystem I/O */
    .struct Stat_blksize_t + 4
Stat_blkcnt_t:               /* Number of 512B blocks allocated */
    .struct Stat_blkcnt_t + 4
Stat_atime:               /*   date et heure fichier */
    .struct Stat_atime + 8
Stat_mtime:               /*   date et heure modif fichier */
    .struct Stat_atime + 8
Stat_ctime:               /*   date et heure creation fichier */
    .struct Stat_atime + 8
Stat_End:

/*********************************/
/* Initialized data              */
/*********************************/
.data
szMessResult:       .asciz " File size = "
szCarriageReturn:   .asciz "\n"
szMessErrOpen:      .asciz "Error open file\n"
szMessErrStat:      .asciz "Error stats file\n"
szFileName:         .asciz "input.txt"
szFileName1:        .asciz "../../../input.txt"
.align 2

/*********************************/
/* UnInitialized data            */
/*********************************/
.bss
sZoneConv:           .skip 24
sBuffer:             .skip Stat_End
/*********************************/
/*  code section                 */
/*********************************/
.text
.global main
main:
    ldr r0,iAdrszFileName       @ file name
    bl filesize
    cmp r0,#0
    blt 100f
    ldr r1,iAdrsZoneConv
    bl conversion10             @ call décimal conversion
    mov r0,#4
    ldr r1,iAdrszFileName
    ldr r2,iAdrszMessResult
    ldr r3,iAdrsZoneConv        @ insert conversion in message
    ldr r4,iAdrszCarriageReturn
    push {r4}
    bl displayStrings           @ display message
    add sp,#4                   @ 1 parameter on stack

    ldr r0,iAdrszFileName1       @ file name
    bl filesize
    cmp r0,#0
    blt 100f
    ldr r1,iAdrsZoneConv
    bl conversion10             @ call décimal conversion
    mov r0,#4
    ldr r1,iAdrszFileName1
    ldr r2,iAdrszMessResult
    ldr r3,iAdrsZoneConv        @ insert conversion in message
    ldr r4,iAdrszCarriageReturn
    push {r4}
    bl displayStrings           @ display message
    add sp,#4                   @ 1 parameter on stack

100:                            @ standard end of the program
    mov r0, #0                  @ return code
    mov r7, #EXIT               @ request to exit program
    svc #0                      @ perform the system call
iAdrszCarriageReturn:    .int szCarriageReturn
iAdrsZoneConv:           .int sZoneConv
iAdrszMessResult:        .int szMessResult
iAdrszFileName:          .int szFileName
iAdrszFileName1:         .int szFileName1
iAdrsBuffer:             .int sBuffer
iAdrszMessErrOpen:       .int szMessErrOpen
iAdrszMessErrStat:       .int szMessErrStat
/***************************************************/
/*   display multi strings                    */
/***************************************************/
/* r0  contains number strings address */
filesize:                       @ INFO:  filesize
    push {r1-r8,fp,lr}          @ save des registres
    mov r1,#O_RDWR              @  flags
    mov r2,#0                   @ mode
    mov r7,#OPEN
    svc 0
    cmp r0,#0                   @ error ?
    ble 99f
    mov r8,r0                   @ Fd save
    ldr r1,iAdrsBuffer          @ buffer address
    mov r7,#NEWFSTAT
    svc 0
    cmp r0,#0
    blt 98f
    ldr r0,iAdrsBuffer
    ldr r1,iAdrsBuffer          @ buffer address
    ldr r4,[r1,#Stat_size_t]    @ file size
    mov r0,r8
    mov r7,#CLOSE
    mov r0,r4                   @ return size
    b 100f
98:
    ldr r0,iAdrszMessErrStat
    bl affichageMess
    mov r0,#-1
    b 100f
99:
    ldr r0,iAdrszMessErrOpen
    bl affichageMess
    mov r0,#-1
100:
    pop {r1-r8,fp,pc}
/***************************************************/
/*   display multi strings                    */
/***************************************************/
/* r0  contains number strings address */
/* r1 address string1 */
/* r2 address string2 */
/* r3 address string3 */
/* other address on the stack */
/* thinck to add  number other address * 4 to add to the stack */
displayStrings:            @ INFO:  displayStrings
    push {r1-r4,fp,lr}     @ save des registres
    add fp,sp,#24          @ save paraméters address (6 registers saved * 4 bytes)
    mov r4,r0              @ save strings number
    cmp r4,#0              @ 0 string -> end
    ble 100f
    mov r0,r1              @ string 1
    bl affichageMess
    cmp r4,#1              @ number > 1
    ble 100f
    mov r0,r2
    bl affichageMess
    cmp r4,#2
    ble 100f
    mov r0,r3
    bl affichageMess
    cmp r4,#3
    ble 100f
    mov r3,#3
    sub r2,r4,#4
1:                            @ loop extract address string on stack
    ldr r0,[fp,r2,lsl #2]
    bl affichageMess
    subs r2,#1
    bge 1b
100:
    pop {r1-r4,fp,pc}
/***************************************************/
/*      ROUTINES INCLUDE                           */
/***************************************************/
.include "../affichage.inc"