en:docs:tk:formats:newexe

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New Executable file format

New Executable (NE) file format used by set of operating system including OS/2, Windows, Multitasking MS-DOS 4 and set of DOS Extenders. It is designed to be store on disk and in-memory usage. In-disk format is same for all OSes, but In-memory usage is mostly specific for Windows systems.

Offset Size Name Description
00h WORD ne_magic Signature word NEMAGIC
On-disk
02h BYTE ne_ver Version number of the linker
03h BYTE ne_rev Revision number of the linker
In-memory
02h WORD count Usage count (ne_ver/ne_rev on disk)
04h WORD ne_enttab Entry Table file offset, relative to the beginning of the segmented EXE header
On-disk
06h WORD ne_cbenttab Number of bytes in the entry table
In-memory
06h WORD next Selector to next module
On-disk
08h DWORD ne_crc 32-bit CRC of entire contents of file. These words are taken as 00 during the calculation
In-memory
08h WORD dgroup_entry Near ptr to segment entry for DGROUP
0Ah WORD fileinfo Near ptr to file info (OFSTRUCT)
0Ch WORD ne_flags Flag word
0Eh WORD ne_autodata Segment number of automatic data segment. This value is set to zero if SINGLEDATA and MULTIPLEDATA flag bits are clear, NOAUTODATA is indicated in the flags word. A Segment number is an index into the module's segment table. The first entry in the segment table is segment number 1
10h WORD ne_heap Initial size, in bytes, of dynamic heap added to the data segment. This value is zero if no initial local heap is allocated
12h WORD ne_stack Initial size, in bytes, of stack added to the data segment. This value is zero to indicate no initial stack allocation, or when SS is not equal to DS
14h DWORD ne_csip Segment number:offset of CS:IP
18h DWORD ne_sssp Segment number:offset of SS:SP
If SS equals the automatic data segment and SP equals zero, the stack pointer is set to the top of the automatic data segment just below the additional heap area.
+————————–+
! additional dynamic heap !
+————————–+ ← SP
! additional stack !
+————————–+
! loaded auto data segment !%
+————————–+ ← DS, SS
1Ch WORD ne_cseg Number of entries in the Segment Table
1Eh WORD ne_cmod Number of entries in the Module Reference Table
20h WORD ne_cbnrestab Number of bytes in the Non-Resident Name Table
22h WORD ne_segtab Segment Table file offset, relative to the beginning of the segmented EXE header
24h WORD ne_rsrctab Resource Table file offset, relative to the beginning of the segmented EXE header
26h WORD ne_restab Resident Name Table file offset, relative to the beginning of the segmented EXE header
28h WORD ne_modtab Module Reference Table file offset, relative to the beginning of the segmented EXE header
2Ah WORD ne_imptab Imported Names Table file offset, relative to the beginning of the segmented EXE header
2Ch DWORD ne_nrestab Non-Resident Name Table offset, relative to the beginning of the file
30h WORD ne_cmovent Number of movable entries in the Entry Table
32h WORD ne_align Logical sector alignment shift count, log(base 2) of the segment sector size (default 9)
34h WORD ne_cres Number of resource entries
36h BYTE ne_exetyp Executable type, used by loader. 02h = WINDOWS
37h BYTE ne_flagsothers Operating system flags
38h WORD ??? offset to return thunks or start of gangload area
3Ah WORD ??? offset to segment reference thunks or length of gangload area
3Ch WORD ??? minimum code swap area size
3Eh 2 BYTEs ??? expected Windows version (minor version first)

On-disk segment entry

Offset Size Name Description
00h WORD ns_sector Logical-sector offset (n byte) to the contents of the segment data, relative to the beginning of the file. Zero means no file data
02h WORD ns_cbseg Length of the segment in the file, in bytes. Zero means 64K
04h WORD ns_flags Flag word
06h WORD ns_minalloc Minimum allocation size of the segment, in bytes. Total size of the segment. Zero means 64K

In-memory segment entry

Offset Size Name Description
00h WORD ns1_sector Logical-sector offset (n byte) to the contents of the segment data, relative to the beginning of the file. Zero means no file data
02h WORD ns1_cbseg Length of the segment in the file, in bytes. Zero means 64K
04h WORD ns1_flags Flag word
06h WORD ns1_minalloc Minimum allocation size of the segment, in bytes. Total size of the segment. Zero means 64K
08h WORD ns1_handle Selector or handle (selector - 1) of segment in memory

struct new_segdata {

  union {
      struct {
          WORD      ns_niter;
          WORD      ns_nbytes;
          char      ns_iterdata;
      } ns_iter;
      struct {
          char      ns_data;
      } ns_noniter;
  } ns_union;

};

Offset Size Name Description
00h WORD nr_nreloc ???

struct new_rlc {

  char            nr_stype;
  char            nr_flags;
  WORD  nr_soff;
  union {
      struct {
          char            nr_segno;
          char            nr_res;
          WORD  nr_entry;
        } nr_intref;
      struct {
          WORD  nr_mod;
          WORD  nr_proc;
        } nr_import;
      struct {
          WORD  nr_ostype;
          WORD  nr_osres;
        } nr_osfix;
    } nr_union;

};

Offset Size Name Description
00h char rs_len ???
01h char rs_string[1] ???
Offset Size Name Description
00h WORD rt_id ???
02h WORD rt_nres ???
04h DWORD rt_proc ???
Offset Size Name Description
00h WORD rn_offset ???
02h WORD rn_length ???
04h WORD rn_flags ???
06h WORD rn_id ???
08h WORD rn_handle ???
0Ah WORD rn_usage ???
Offset Size Name Description
00h WORD rs_align ???
02h struct rsrc_typeinfo rs_typeinfo ???