x86_64_sse2_x87/pbf/features/motorway.s

   1 ; vim: set filetype=fasm foldmethod=marker commentstring=;%s colorcolumn=101 :
   2 motorway: namespace motorway
   3 ; input:
   4 ;       rdi = tile_p
   5 ;       rsi = offset of the way in the tile db
   6 ;       rdx = node_p of the one provoking this very tile addition, only used if initing required
   7 align_nops
   8 import:
   9 define tile_p                   rbx
  10 define rbx_save                 rsp + 8 * 0
  11 define r12_save                 rsp + 8 * 1
  12 define r13_save                 rsp + 8 * 2
  13 define motorway_of              rsp + 8 * 3
  14         enter 8 * 4, 0
  15         and rsp, not 0xf ; align stack for external calls
  16         mov [rbx_save], rbx
  17
  18         mov tile_p, rdi
  19         mov [motorway_of], rsi
  20
  21         bt qword [tile_p + tile_t.flags], tile_t.flags.motorways_inited
  22                 jnc motorways_init
  23         mov rdi, qword [tile_p + tile_t.features.motorways.fd]
  24 motorways_inited:
  25         ; write the offset into the array of the ways in the tile motorways ------------------------
  26         lea rsi, [motorway_of]
  27         mov rdx, 8
  28         mov rax, linux.write
  29         syscall
  30         cmp rax, linux.errno.last
  31                 jae err_write_motorway_of_failed
  32         stc
  33 epilog:
  34         mov rbx, qword [rbx_save]
  35         leave
  36         ret
  37         ;-------------------------------------------------------------------------------------------
  38         ; we presume created directories
  39 define node_p           r12 ; r12 due te re-using tile init code
  40 define path_finish      r13 ; r13 due to re-using tile init code
  41 motorways_init:
  42         ; build the path re-using tile init code ---------------------------------------------------
  43         mov [r12_save], r12
  44         mov [r13_save], r13
  45         mov node_p, rdx
  46         call tile.init.xy_to_str ; we share r12 and r13
  47         call tile.init.path_tile_dir_do ; we share r12 and r13
  48         mov r12, qword [r12_save]
  49 purge node_p
  50         mov rax, '/motorwa'
  51         mov qword [path_finish], rax
  52         mov eax, 'ys'
  53         mov dword [path_finish + 8], eax ; 0 terminator added
  54         mov r13, qword [r13_save]
  55 purge path_finish
  56         ; get a fd ---------------------------------------------------------------------------------
  57         mov rax, [ctx]
  58         mov rdi, [rax + ctx_t.tile_db_dir.fd]
  59         lea rsi, [tile.init.path]
  60         mov rdx, linux.O_CREAT or linux.O_TRUNC or linux.O_WRONLY
  61         mov r10, 110110110b ; RW for all but umask
  62         mov rax, linux.openat
  63         syscall
  64         cmp rax, linux.errno.last
  65                 jae err_motorways_openat_failed
  66         mov [tile_p + tile_t.features.motorways.fd], rax
  67         mov rdi, rax ; caller expect the fd being in rdi as well
  68
  69         or qword [tile_p + tile_t.flags], 1 shl tile_t.flags.motorways_inited
  70         jmp motorways_inited
  71         ;-------------------------------------------------------------------------------------------
  72 err_motorways_openat_failed:
  73         mov rdi, 2
  74         lea rsi, [msg.err_motorways_openat_failed]
  75         mov rdx, rax
  76         lea rcx, [tile.init.path]
  77         call qword [libc.dprintf]
  78         clc
  79         jmp epilog
  80 err_write_motorway_of_failed:
  81         mov rdi, 2
  82         lea rsi, [msg.err_write_motorway_of_failed]
  83         mov rdx, rax
  84         call qword [libc.dprintf]
  85         clc
  86         jmp epilog
  87 purge tile_p
  88 purge rbx_save
  89 purge r12_save
  90 purge r13_save
  91 purge motorway_of
  92 end namespace ; motorways