nasm/rdoff/rdoff.h
H. Peter Anvin 225c5926f0 NASM 0.98.22
2002-04-30 21:06:16 +00:00

206 lines
6.5 KiB
C

/* rdoff.h RDOFF Object File manipulation routines header file
*
* The Netwide Assembler is copyright (C) 1996 Simon Tatham and
* Julian Hall. All rights reserved. The software is
* redistributable under the licence given in the file "Licence"
* distributed in the NASM archive.
*
* Permission to use this file in your own projects is granted, as long
* as acknowledgement is given in an appropriate manner to its authors,
* with instructions of how to obtain a copy via ftp.
*/
#ifndef _RDOFF_H
#define _RDOFF_H "RDOFF2 support routines v0.3"
/* Some systems don't define this automatically */
extern char *strdup(const char *);
typedef unsigned short int16;
typedef unsigned char byte;
#define RDF_MAXSEGS 64
/* the records that can be found in the RDOFF header */
struct RelocRec {
byte type; /* must be 1 */
byte reclen; /* content length */
byte segment; /* only 0 for code, or 1 for data supported,
but add 64 for relative refs (ie do not require
reloc @ loadtime, only linkage) */
long offset; /* from start of segment in which reference is loc'd */
byte length; /* 1 2 or 4 bytes */
int16 refseg; /* segment to which reference refers to */
};
struct ImportRec {
byte type; /* must be 2 */
byte reclen; /* content length */
int16 segment; /* segment number allocated to the label for reloc
records - label is assumed to be at offset zero
in this segment, so linker must fix up with offset
of segment and of offset within segment */
char label[33]; /* zero terminated... should be written to file until
the zero, but not after it - max len = 32 chars */
};
struct ExportRec {
byte type; /* must be 3 */
byte reclen; /* content length */
byte flags; /* SYM_* flags (see below) */
byte segment; /* segment referred to (0/1/2) */
long offset; /* offset within segment */
char label[33]; /* zero terminated as above. max len = 32 chars */
};
struct DLLRec {
byte type; /* must be 4 */
byte reclen; /* content length */
char libname[128]; /* name of library to link with at load time */
};
struct BSSRec {
byte type; /* must be 5 */
byte reclen; /* content length */
long amount; /* number of bytes BSS to reserve */
};
struct ModRec {
byte type; /* must be 8 */
byte reclen; /* content length */
char modname[128]; /* module name */
};
/* Flags for ExportRec */
#define SYM_DATA 0x01
#define SYM_FUNCTION 0x02
#define SYM_GLOBAL 0x04
#ifdef _MULTBOOT_H
#define RDFLDRMOVER_SIZE 22
struct MultiBootHdrRec {
byte type; /* must be 9 */
byte reclen; /* content length */
#ifdef __GNUC__
struct tMultiBootHeader mb __attribute__ ((packed)); /* MultiBoot header */
#else
struct tMultiBootHeader mb;
#endif
byte mover[RDFLDRMOVER_SIZE]; /* Mover of RDF loader */
};
#endif
/* GenericRec - contains the type and length field, plus a 128 byte
char array 'data', which will probably never be used! */
struct GenericRec {
byte type;
byte reclen;
char data[128];
};
typedef union RDFHeaderRec {
char type; /* invariant throughout all below */
struct GenericRec g;
struct RelocRec r; /* type == 1 / 6 */
struct ImportRec i; /* type == 2 / 7 */
struct ExportRec e; /* type == 3 */
struct DLLRec d; /* type == 4 */
struct BSSRec b; /* type == 5 */
struct ModRec m; /* type == 8 */
#ifdef _MULTBOOT_H
struct MultiBootHdrRec mbh; /* type == 9 */
#endif
} rdfheaderrec;
struct SegmentHeaderRec {
/* information from file */
int16 type;
int16 number;
int16 reserved;
long length;
/* information built up here */
long offset;
byte *data; /* pointer to segment data if it exists in memory */
};
typedef struct RDFFileInfo {
FILE *fp; /* file descriptor; must be open to use this struct */
int rdoff_ver; /* should be 1; any higher => not guaranteed to work */
long header_len;
long header_ofs;
byte *header_loc; /* keep location of header */
long header_fp; /* current location within header for reading */
struct SegmentHeaderRec seg[RDF_MAXSEGS];
int nsegs;
long eof_offset; /* offset of the first byte beyond the end of this
module */
char *name; /* name of module in libraries */
int *refcount; /* pointer to reference count on file, or NULL */
} rdffile;
#define BUF_BLOCK_LEN 4088 /* selected to match page size (4096)
* on 80x86 machines for efficiency */
typedef struct memorybuffer {
int length;
byte buffer[BUF_BLOCK_LEN];
struct memorybuffer *next;
} memorybuffer;
typedef struct {
memorybuffer * buf; /* buffer containing header records */
int nsegments; /* number of segments to be written */
long seglength; /* total length of all the segments */
} rdf_headerbuf;
/* segments used by RDOFF, understood by rdoffloadseg */
#define RDOFF_CODE 0
#define RDOFF_DATA 1
#define RDOFF_HEADER -1
/* mask for 'segment' in relocation records to find if relative relocation */
#define RDOFF_RELATIVEMASK 64
/* mask to find actual segment value in relocation records */
#define RDOFF_SEGMENTMASK 63
extern int rdf_errno;
/* utility functions */
int16 translateshort(int16 in);
long translatelong(long in);
/* RDOFF file manipulation functions */
int rdfopen(rdffile *f,const char *name);
int rdfopenhere(rdffile *f, FILE *fp, int *refcount, const char *name);
int rdfclose(rdffile *f);
int rdffindsegment(rdffile * f, int segno);
int rdfloadseg(rdffile *f,int segment,void *buffer);
rdfheaderrec *rdfgetheaderrec(rdffile *f); /* returns static storage */
void rdfheaderrewind(rdffile *f); /* back to start of header */
void rdfperror(const char *app,const char *name);
/* functions to write a new RDOFF header to a file -
use rdfnewheader to allocate a header, rdfaddheader to add records to it,
rdfaddsegment to notify the header routines that a segment exists, and
to tell it how long the segment will be.
rdfwriteheader to write the file id, object length, and header
to a file, and then rdfdoneheader to dispose of the header */
rdf_headerbuf *rdfnewheader(void);
int rdfaddheader(rdf_headerbuf *h,rdfheaderrec *r);
int rdfaddsegment(rdf_headerbuf *h, long seglength);
int rdfwriteheader(FILE *fp,rdf_headerbuf *h);
void rdfdoneheader(rdf_headerbuf *h);
/* This is needed by linker to write multiboot header record */
int membuflength(memorybuffer *b);
#endif /* _RDOFF_H */