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; param

;  eax= required size

;

; retval

;  edi= memory block descriptor

;  ebx= descriptor index

align 4

get_large_block:

           mov edx, -1

           mov ecx, eax

           shr ecx, 22

           dec ecx

           cmp ecx, 31

           jle .get_index

           mov ecx, 31

.get_index:

           shl edx, cl

           and edx, [large_block_mask]

.find:

           bsf edi, edx

           mov ebx, edi

           mov edi, [large_block_list+edi*4]

.check_size:

           cmp eax, [edi+block_size]

           ja .next

           ret

.next:

           mov edi, [edi+list_fd]

           test edi, edi

           jnz .check_size

.fail:

           xor edi, edi

           ret

align 4

proc alloc_large stdcall, size:dword

           local block_ind:DWORD

           push ebx

           push esi

           push edi

           mov eax, [size]

           add eax, 0x3FFFFF

           and eax, not 0x3FFFFF

           mov [size], eax

         ;  mov ebx, heap_mutex

         ;  call wait_mutex    ;ebx

         ;  cmp eax, [heap_free]

         ;  ja .error

           call get_large_block ; eax

           test edi, edi

           jz .error

           cmp [edi+block_flags], FREE_BLOCK

           jne .error

           mov [block_ind], ebx   ;index of allocated block

           mov eax, [edi+block_size]

           cmp eax, [size]

           je .m_eq_size

           call alloc_mem_block

           and eax, eax

           jz .error

           mov esi, eax           ;esi - splitted block

           mov [esi+block_next], edi

           mov eax, [edi+block_prev]

           mov [esi+block_prev], eax

           mov [edi+block_prev], esi

           mov [esi+list_fd], 0

           mov [esi+list_bk], 0

           test eax, eax

           jz @f

           mov [eax+block_next], esi

@@:

           mov ebx, [edi+block_base]

           mov [esi+block_base], ebx

           mov edx, [size]

           mov [esi+block_size], edx

           add [edi+block_base], edx

           sub [edi+block_size], edx

           mov eax, [edi+block_size]

           shr eax, 22

           dec eax

           cmp eax, 31

           jna @f

           mov eax, 31

@@:

           cmp eax, [block_ind]

           je .m_eq_ind

           remove_from_list edi

           mov ecx, [block_ind]

           mov [large_block_list+ecx*4], edx

           test edx, edx

           jnz @f

           btr [large_block_mask], ecx

@@:

           mov edx, [large_block_list+eax*4]

           mov [edi+list_fd], edx

           test edx, edx

           jz @f

           mov [edx+list_bk], edi

@@:

           mov [large_block_list+eax*4], edi

           bts [large_block_mask], eax

.m_eq_ind:

           mov ecx, mem_used.fd-MEM_LIST_OFFSET

           mov edx, [ecx+list_fd]

           mov [esi+list_fd], edx

           mov [esi+list_bk], ecx

           mov [ecx+list_fd], esi

           mov [edx+list_bk], esi

           mov [esi+block_flags], USED_BLOCK

           mov eax, [esi+block_base]

           mov ebx, [size]

           sub [heap_free], ebx

           and [heap_mutex], 0

           pop edi

           pop esi

           pop ebx

           ret

.m_eq_size:

           remove_from_list edi

           mov [large_block_list+ebx*4], edx

           and edx, edx

           jnz @f

           btr [large_block_mask], ebx

@@:

           mov ecx, mem_used.fd-MEM_LIST_OFFSET

           mov edx, [ecx+list_fd]

           mov [edi+list_fd], edx

           mov [edi+list_bk], ecx

           mov [ecx+list_fd], edi

           mov [edx+list_bk], edi

           mov [edi+block_flags], USED_BLOCK

           mov eax, [edi+block_base]

           mov ebx, [size]

           sub [heap_free], ebx

           and [heap_mutex], 0

           pop edi

           pop esi

           pop ebx

           ret

.error:

           xor eax, eax

           mov [heap_mutex], eax

           pop edi

           pop esi

           pop ebx

           ret

endp