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Diffstat (limited to 'include/linux/coff.h')
| -rw-r--r-- | include/linux/coff.h | 351 |
1 files changed, 351 insertions, 0 deletions
diff --git a/include/linux/coff.h b/include/linux/coff.h new file mode 100644 index 0000000..6354a7f --- /dev/null +++ b/include/linux/coff.h @@ -0,0 +1,351 @@ +/* This file is derived from the GAS 2.1.4 assembler control file. + The GAS product is under the GNU General Public License, version 2 or later. + As such, this file is also under that license. + + If the file format changes in the COFF object, this file should be + subsequently updated to reflect the changes. + + The actual loader module only uses a few of these structures. The full + set is documented here because I received the full set. If you wish + more information about COFF, then O'Reilly has a very excellent book. +*/ + +#define E_SYMNMLEN 8 /* Number of characters in a symbol name */ +#define E_FILNMLEN 14 /* Number of characters in a file name */ +#define E_DIMNUM 4 /* Number of array dimensions in auxiliary entry */ + +/* + * These defines are byte order independent. There is no alignment of fields + * permitted in the structures. Therefore they are declared as characters + * and the values loaded from the character positions. It also makes it + * nice to have it "endian" independent. + */ + +/* Load a short int from the following tables with little-endian formats */ +#define COFF_SHORT_L(ps) ((short)(((unsigned short)((unsigned char)ps[1])<<8)|\ + ((unsigned short)((unsigned char)ps[0])))) + +/* Load a long int from the following tables with little-endian formats */ +#define COFF_LONG_L(ps) (((long)(((unsigned long)((unsigned char)ps[3])<<24) |\ + ((unsigned long)((unsigned char)ps[2])<<16) |\ + ((unsigned long)((unsigned char)ps[1])<<8) |\ + ((unsigned long)((unsigned char)ps[0]))))) + +/* Load a short int from the following tables with big-endian formats */ +#define COFF_SHORT_H(ps) ((short)(((unsigned short)((unsigned char)ps[0])<<8)|\ + ((unsigned short)((unsigned char)ps[1])))) + +/* Load a long int from the following tables with big-endian formats */ +#define COFF_LONG_H(ps) (((long)(((unsigned long)((unsigned char)ps[0])<<24) |\ + ((unsigned long)((unsigned char)ps[1])<<16) |\ + ((unsigned long)((unsigned char)ps[2])<<8) |\ + ((unsigned long)((unsigned char)ps[3]))))) + +/* These may be overridden later by brain dead implementations which generate + a big-endian header with little-endian data. In that case, generate a + replacement macro which tests a flag and uses either of the two above + as appropriate. */ + +#define COFF_LONG(v) COFF_LONG_L(v) +#define COFF_SHORT(v) COFF_SHORT_L(v) + +/*** coff information for Intel 386/486. */ + +/********************** FILE HEADER **********************/ + +struct COFF_filehdr { + char f_magic[2]; /* magic number */ + char f_nscns[2]; /* number of sections */ + char f_timdat[4]; /* time & date stamp */ + char f_symptr[4]; /* file pointer to symtab */ + char f_nsyms[4]; /* number of symtab entries */ + char f_opthdr[2]; /* sizeof(optional hdr) */ + char f_flags[2]; /* flags */ +}; + +/* + * Bits for f_flags: + * + * F_RELFLG relocation info stripped from file + * F_EXEC file is executable (i.e. no unresolved external + * references) + * F_LNNO line numbers stripped from file + * F_LSYMS local symbols stripped from file + * F_MINMAL this is a minimal object file (".m") output of fextract + * F_UPDATE this is a fully bound update file, output of ogen + * F_SWABD this file has had its bytes swabbed (in names) + * F_AR16WR this file has the byte ordering of an AR16WR + * (e.g. 11/70) machine + * F_AR32WR this file has the byte ordering of an AR32WR machine + * (e.g. vax and iNTEL 386) + * F_AR32W this file has the byte ordering of an AR32W machine + * (e.g. 3b,maxi) + * F_PATCH file contains "patch" list in optional header + * F_NODF (minimal file only) no decision functions for + * replaced functions + */ + +#define COFF_F_RELFLG 0000001 +#define COFF_F_EXEC 0000002 +#define COFF_F_LNNO 0000004 +#define COFF_F_LSYMS 0000010 +#define COFF_F_MINMAL 0000020 +#define COFF_F_UPDATE 0000040 +#define COFF_F_SWABD 0000100 +#define COFF_F_AR16WR 0000200 +#define COFF_F_AR32WR 0000400 +#define COFF_F_AR32W 0001000 +#define COFF_F_PATCH 0002000 +#define COFF_F_NODF 0002000 + +#define COFF_I386MAGIC 0x14c /* Linux's system */ + +#if 0 /* Perhaps, someday, these formats may be used. */ +#define COFF_I386PTXMAGIC 0x154 +#define COFF_I386AIXMAGIC 0x175 /* IBM's AIX system */ +#define COFF_I386BADMAG(x) ((COFF_SHORT((x).f_magic) != COFF_I386MAGIC) \ + && COFF_SHORT((x).f_magic) != COFF_I386PTXMAGIC \ + && COFF_SHORT((x).f_magic) != COFF_I386AIXMAGIC) +#else +#define COFF_I386BADMAG(x) (COFF_SHORT((x).f_magic) != COFF_I386MAGIC) +#endif + +#define COFF_FILHDR struct COFF_filehdr +#define COFF_FILHSZ sizeof(COFF_FILHDR) + +/********************** AOUT "OPTIONAL HEADER" **********************/ + +/* Linux COFF must have this "optional" header. Standard COFF has no entry + location for the "entry" point. They normally would start with the first + location of the .text section. This is not a good idea for linux. So, + the use of this "optional" header is not optional. It is required. + + Do not be tempted to assume that the size of the optional header is + a constant and simply index the next byte by the size of this structure. + Use the 'f_opthdr' field in the main coff header for the size of the + structure actually written to the file!! +*/ + +typedef struct +{ + char magic[2]; /* type of file */ + char vstamp[2]; /* version stamp */ + char tsize[4]; /* text size in bytes, padded to FW bdry */ + char dsize[4]; /* initialized data " " */ + char bsize[4]; /* uninitialized data " " */ + char entry[4]; /* entry pt. */ + char text_start[4]; /* base of text used for this file */ + char data_start[4]; /* base of data used for this file */ +} +COFF_AOUTHDR; + +#define COFF_AOUTSZ (sizeof(COFF_AOUTHDR)) + +#define COFF_STMAGIC 0401 +#define COFF_OMAGIC 0404 +#define COFF_JMAGIC 0407 /* dirty text and data image, can't share */ +#define COFF_DMAGIC 0410 /* dirty text segment, data aligned */ +#define COFF_ZMAGIC 0413 /* The proper magic number for executables */ +#define COFF_SHMAGIC 0443 /* shared library header */ + +/********************** SECTION HEADER **********************/ + +struct COFF_scnhdr { + char s_name[8]; /* section name */ + char s_paddr[4]; /* physical address, aliased s_nlib */ + char s_vaddr[4]; /* virtual address */ + char s_size[4]; /* section size */ + char s_scnptr[4]; /* file ptr to raw data for section */ + char s_relptr[4]; /* file ptr to relocation */ + char s_lnnoptr[4]; /* file ptr to line numbers */ + char s_nreloc[2]; /* number of relocation entries */ + char s_nlnno[2]; /* number of line number entries */ + char s_flags[4]; /* flags */ +}; + +#define COFF_SCNHDR struct COFF_scnhdr +#define COFF_SCNHSZ sizeof(COFF_SCNHDR) + +/* + * names of "special" sections + */ + +#define COFF_TEXT ".text" +#define COFF_DATA ".data" +#define COFF_BSS ".bss" +#define COFF_COMMENT ".comment" +#define COFF_LIB ".lib" + +#define COFF_SECT_TEXT 0 /* Section for instruction code */ +#define COFF_SECT_DATA 1 /* Section for initialized globals */ +#define COFF_SECT_BSS 2 /* Section for un-initialized globals */ +#define COFF_SECT_REQD 3 /* Minimum number of sections for good file */ + +#define COFF_STYP_REG 0x00 /* regular segment */ +#define COFF_STYP_DSECT 0x01 /* dummy segment */ +#define COFF_STYP_NOLOAD 0x02 /* no-load segment */ +#define COFF_STYP_GROUP 0x04 /* group segment */ +#define COFF_STYP_PAD 0x08 /* .pad segment */ +#define COFF_STYP_COPY 0x10 /* copy section */ +#define COFF_STYP_TEXT 0x20 /* .text segment */ +#define COFF_STYP_DATA 0x40 /* .data segment */ +#define COFF_STYP_BSS 0x80 /* .bss segment */ +#define COFF_STYP_INFO 0x200 /* .comment section */ +#define COFF_STYP_OVER 0x400 /* overlay section */ +#define COFF_STYP_LIB 0x800 /* library section */ + +/* + * Shared libraries have the following section header in the data field for + * each library. + */ + +struct COFF_slib { + char sl_entsz[4]; /* Size of this entry */ + char sl_pathndx[4]; /* size of the header field */ +}; + +#define COFF_SLIBHD struct COFF_slib +#define COFF_SLIBSZ sizeof(COFF_SLIBHD) + +/********************** LINE NUMBERS **********************/ + +/* 1 line number entry for every "breakpointable" source line in a section. + * Line numbers are grouped on a per function basis; first entry in a function + * grouping will have l_lnno = 0 and in place of physical address will be the + * symbol table index of the function name. + */ + +struct COFF_lineno { + union { + char l_symndx[4]; /* function name symbol index, iff l_lnno == 0*/ + char l_paddr[4]; /* (physical) address of line number */ + } l_addr; + char l_lnno[2]; /* line number */ +}; + +#define COFF_LINENO struct COFF_lineno +#define COFF_LINESZ 6 + +/********************** SYMBOLS **********************/ + +#define COFF_E_SYMNMLEN 8 /* # characters in a short symbol name */ +#define COFF_E_FILNMLEN 14 /* # characters in a file name */ +#define COFF_E_DIMNUM 4 /* # array dimensions in auxiliary entry */ + +/* + * All symbols and sections have the following definition + */ + +struct COFF_syment +{ + union { + char e_name[E_SYMNMLEN]; /* Symbol name (first 8 characters) */ + struct { + char e_zeroes[4]; /* Leading zeros */ + char e_offset[4]; /* Offset if this is a header section */ + } e; + } e; + + char e_value[4]; /* Value (address) of the segment */ + char e_scnum[2]; /* Section number */ + char e_type[2]; /* Type of section */ + char e_sclass[1]; /* Loader class */ + char e_numaux[1]; /* Number of auxiliary entries which follow */ +}; + +#define COFF_N_BTMASK (0xf) /* Mask for important class bits */ +#define COFF_N_TMASK (0x30) /* Mask for important type bits */ +#define COFF_N_BTSHFT (4) /* # bits to shift class field */ +#define COFF_N_TSHIFT (2) /* # bits to shift type field */ + +/* + * Auxiliary entries because the main table is too limiting. + */ + +union COFF_auxent { + +/* + * Debugger information + */ + + struct { + char x_tagndx[4]; /* str, un, or enum tag indx */ + union { + struct { + char x_lnno[2]; /* declaration line number */ + char x_size[2]; /* str/union/array size */ + } x_lnsz; + char x_fsize[4]; /* size of function */ + } x_misc; + + union { + struct { /* if ISFCN, tag, or .bb */ + char x_lnnoptr[4]; /* ptr to fcn line # */ + char x_endndx[4]; /* entry ndx past block end */ + } x_fcn; + + struct { /* if ISARY, up to 4 dimen. */ + char x_dimen[E_DIMNUM][2]; + } x_ary; + } x_fcnary; + + char x_tvndx[2]; /* tv index */ + } x_sym; + +/* + * Source file names (debugger information) + */ + + union { + char x_fname[E_FILNMLEN]; + struct { + char x_zeroes[4]; + char x_offset[4]; + } x_n; + } x_file; + +/* + * Section information + */ + + struct { + char x_scnlen[4]; /* section length */ + char x_nreloc[2]; /* # relocation entries */ + char x_nlinno[2]; /* # line numbers */ + } x_scn; + +/* + * Transfer vector (branch table) + */ + + struct { + char x_tvfill[4]; /* tv fill value */ + char x_tvlen[2]; /* length of .tv */ + char x_tvran[2][2]; /* tv range */ + } x_tv; /* info about .tv section (in auxent of symbol .tv)) */ +}; + +#define COFF_SYMENT struct COFF_syment +#define COFF_SYMESZ 18 +#define COFF_AUXENT union COFF_auxent +#define COFF_AUXESZ 18 + +#define COFF_ETEXT "etext" + +/********************** RELOCATION DIRECTIVES **********************/ + +struct COFF_reloc { + char r_vaddr[4]; /* Virtual address of item */ + char r_symndx[4]; /* Symbol index in the symtab */ + char r_type[2]; /* Relocation type */ +}; + +#define COFF_RELOC struct COFF_reloc +#define COFF_RELSZ 10 + +#define COFF_DEF_DATA_SECTION_ALIGNMENT 4 +#define COFF_DEF_BSS_SECTION_ALIGNMENT 4 +#define COFF_DEF_TEXT_SECTION_ALIGNMENT 4 + +/* For new sections we haven't heard of before */ +#define COFF_DEF_SECTION_ALIGNMENT 4 |
