rsalz@uunet.uu.net (Rich Salz) (05/25/88)
Submitted-by: "G. M. Harding" <gm@uts.amdahl.com>
Posting-number: Volume 15, Issue 6
Archive-name: dis88/part01
[ I packed up the archives and turned the formatted manpage
into an unformatted one. --r$ ]
"Dis88" is a symbolic disassembler for the Intel 8088 CPU,
designed to run under the PC/IX operating system on an IBM XT
or fully-compatible clone. Its output is in the format of, and
is completely compatible with, the PC/IX assembler, "as". The
program is copyrighted by its author, but may be copied and re-
distributed freely provided that complete source code, with all
copyright notices, accompanies any distribution. This provision
also applies to any modifications you may make. You are urged
to comment such changes, giving, as a miminum, your name and
complete address.
---
G. M. HARDING
POB 4142
Santa Clara CA 95054-0142
#! /bin/sh
# This is a shell archive. Remove anything before this line, then unpack
# it by saving it into a file and typing "sh file". To overwrite existing
# files, type "sh file -c". You can also feed this as standard input via
# unshar, or by typing "sh <file", e.g.. If this archive is complete, you
# will see the following message at the end:
# "End of archive 1 (of 2)."
PATH=/bin:/usr/bin:/usr/ucb ; export PATH
if test -f 'MANIFEST' -a "${1}" != "-c" ; then
echo shar: Will not clobber existing file \"'MANIFEST'\"
else
echo shar: Extracting \"'MANIFEST'\" \(406 characters\)
sed "s/^X//" >'MANIFEST' <<'END_OF_FILE'
X File Name Archive # Description
X-----------------------------------------------------------
X MANIFEST 1
X Makefile 1
X README 1
X dis.h 1
X dis88.1 1
X disfp.c 1
X dishand.c 2
X dismain.c 1
X disrel.c 1
X distabs.c 2
END_OF_FILE
if test 406 -ne `wc -c <'MANIFEST'`; then
echo shar: \"'MANIFEST'\" unpacked with wrong size!
fi
# end of 'MANIFEST'
fi
if test -f 'Makefile' -a "${1}" != "-c" ; then
echo shar: Will not clobber existing file \"'Makefile'\"
else
echo shar: Extracting \"'Makefile'\" \(1593 characters\)
sed "s/^X//" >'Makefile' <<'END_OF_FILE'
X# @(#) Makefile, Ver. 2.1 created 00:00:00 87/09/01
X# Makefile for 8088 symbolic disassembler
X
X# Copyright (C) 1987 G. M. Harding, all rights reserved.
X# Permission to copy and redistribute is hereby granted,
X# provided full source code, with all copyright notices,
X# accompanies any redistribution.
X
X# This Makefile automates the process of compiling and linking
X# a symbolic object-file disassembler program for the Intel
X# 8088 CPU. Relatively machine-independent code is contained in
X# the file dismain.c; lookup tables and handler routines, which
X# are by their nature machine-specific, are contained in two
X# files named distabs.c and dishand.c, respectively. (A third
X# machine-specific file, disfp.c, contains handler routines for
X# floating-point coprocessor opcodes.) A header file, dis.h,
X# attempts to mediate between the machine-specific and machine-
X# independent portions of the code. An attempt has been made to
X# isolate machine dependencies and to deal with them in fairly
X# straightforward ways. Thus, it should be possible to target a
X# different CPU by rewriting the handler routines and changing
X# the initialization data in the lookup tables. It should not
X# be necessary to alter the formats of the tables.
X
OBJ = disrel.o dismain.o distabs.o dishand.o disfp.o
X
dis88 : $(OBJ)
X ld -i -s -o dis88 /lib/crt0.o $(OBJ) -lc
X size dis88
X @echo "\07Build of 'dis88' complete." > /dev/tty
X
X.c.o :
X cc -O -c $<
X chmod 600 $*.o
X
disrel.o : disrel.c
X
dismain.o : dismain.c dis.h
X
distabs.o : distabs.c dis.h
X
dishand.o : dishand.c dis.h
X
disfp.o : disfp.c dis.h
X
END_OF_FILE
if test 1593 -ne `wc -c <'Makefile'`; then
echo shar: \"'Makefile'\" unpacked with wrong size!
fi
# end of 'Makefile'
fi
if test -f 'README' -a "${1}" != "-c" ; then
echo shar: Will not clobber existing file \"'README'\"
else
echo shar: Extracting \"'README'\" \(4898 characters\)
sed "s/^X//" >'README' <<'END_OF_FILE'
X dis88
X Beta Release
X 87/09/01
X ---
X G. M. HARDING
X POB 4142
X Santa Clara CA 95054-0142
X
X
X "Dis88" is a symbolic disassembler for the Intel 8088 CPU,
X designed to run under the PC/IX operating system on an IBM XT
X or fully-compatible clone. Its output is in the format of, and
X is completely compatible with, the PC/IX assembler, "as". The
X program is copyrighted by its author, but may be copied and re-
X distributed freely provided that complete source code, with all
X copyright notices, accompanies any distribution. This provision
X also applies to any modifications you may make. You are urged
X to comment such changes, giving, as a miminum, your name and
X complete address.
X
X This release of the program is a beta release, which means
X that it has been extensively, but not exhaustively, tested.
X User comments, recommendations, and bug fixes are welcome. The
X principal features of the current release are:
X
X (a) The ability to disassemble any file in PC/IX object
X format, making full use of symbol and relocation information if
X it is present, regardless of whether the file is executable or
X linkable, and regardless of whether it has continuous or split
X I/D space;
X
X (b) Automatic generation of synthetic labels when no sym-
X bol table is available; and
X
X (c) Optional output of address and object-code informa-
X tion as assembler comment text.
X
X Limitations of the current release are:
X
X (a) Numeric co-processor (i.e., 8087) mnemonics are not
X supported. Instructions for the co-processor are disassembled
X as CPU escape sequences, or as interrupts, depending on how
X they were assembled in the first place. This limitation will be
X addressed in a future release.
X
X (b) Symbolic references within the object file's data
X segment are not supported. Thus, for example, if a data segment
X location is initialized to point to a text segment address, no
X reference to a text segment symbol will be detected. This limi-
X tation is likely to remain in future releases, because object
X code does not, in most cases, contain sufficient information to
X allow meaningful interpretation of pure data. (Note, however,
X that symbolic references to the data segment from within the
X text segment are always supported.)
X
X As a final caveat, be aware that the PC/IX assembler does
X not recognize the "esc" mnemonic, even though it refers to a
X completely valid CPU operation which is documented in all the
X Intel literature. Thus, the corresponding opcodes (0xd8 through
X 0xdf) are disassembled as .byte directives. For reference, how-
X ever, the syntactically-correct "esc" instruction is output as
X a comment.
X
X To build the disassembler program, transfer all the source
X files, together with the Makefile, to a suitable (preferably
X empty) PC/IX directory. Then, simply type "make".
X
X To use dis88, place it in a directory which appears in
X your $PATH list. It may then be invoked by name from whatever
X directory you happen to be in. As a minimum, the program must
X be invoked with one command-line argument: the name of the ob-
X ject file to be disassembled. (Dis88 will complain if the file
X specified is not an object file.) Optionally, you may specify
X an output file; stdout is the default. One command-line switch
X is available: "-o", which makes the program display addresses
X and object code along with its mnemonic disassembly.
X
X The "-o" option is useful primarily for verifying the cor-
X rectness of the program's output. In particular, it may be used
X to check the accuracy of local relative jump opcodes. These
X jumps often target local labels, which are lost at assembly
X time; thus, the disassembly may contain cryptic instructions
X like "jnz .+39". As a user convenience, all relative jump and
X call opcodes are output with a comment which identifies the
X physical target address.
X
X By convention, the release level of the program as a whole
X is the SID of the file disrel.c, and this SID string appears in
X each disassembly. Release 2.1 of the program is the first beta
X release to be distributed on Usenet.
X
END_OF_FILE
if test 4898 -ne `wc -c <'README'`; then
echo shar: \"'README'\" unpacked with wrong size!
fi
# end of 'README'
fi
if test -f 'dis.h' -a "${1}" != "-c" ; then
echo shar: Will not clobber existing file \"'dis.h'\"
else
echo shar: Extracting \"'dis.h'\" \(7563 characters\)
sed "s/^X//" >'dis.h' <<'END_OF_FILE'
X /*
X ** @(#) dis.h, Ver. 2.1 created 00:00:00 87/09/01
X */
X
X /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
X * *
X * Copyright (C) 1987 G. M. Harding, all rights reserved *
X * *
X * Permission to copy and redistribute is hereby granted, *
X * provided full source code, with all copyright notices, *
X * accompanies any redistribution. *
X * *
X * This file contains declarations and definitions used by *
X * the 8088 disassembler program. The program was designed *
X * for execution on a machine of its own type (i.e., it is *
X * not designed as a cross-disassembler); consequently, A *
X * SIXTEEN-BIT INTEGER SIZE HAS BEEN ASSUMED. This assump- *
X * tion is not particularly important, however, except in *
X * the machine-specific portions of the code (i.e., the *
X * handler routines and the optab[] array). It should be *
X * possible to override this assumption, for execution on *
X * 32-bit machines, by use of a pre-processor directive *
X * (see below); however, this has not been tested. *
X * *
X * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
X
X#include <stdio.h> /* System standard I/O definitions */
X#include <fcntl.h> /* System file-control definitions */
X#include <a.out.h> /* Object file format definitions */
X
X#if i8086 || i8088 /* For CPU's with 16-bit integers */
X#undef int
X#else /* Defaults (for 32-bit CPU types) */
X#define int short
X#endif
X
X#define MAXSYM 1500 /* Maximum entries in symbol table */
X
extern struct nlist /* Array to hold the symbol table */
X symtab[MAXSYM];
X
extern struct reloc /* Array to hold relocation table */
X relo[MAXSYM];
X
extern int symptr; /* Index into the symtab[] array */
X
extern int relptr; /* Index into the relo[] array */
X
struct opcode /* Format for opcode data records */
X {
X char *text; /* Pointer to mnemonic text */
X void (*func)(); /* Pointer to handler routine */
X unsigned min; /* Minimum # of object bytes */
X unsigned max; /* Maximum # of object bytes */
X };
X
extern struct opcode /* Array to hold the opcode table */
X optab[256];
X
X /*
X +---------------------------------------------
X | The following functions are the specialized
X | handlers for each opcode group. They are, of
X | course, highly MACHINE-SPECIFIC. Each entry
X | in the opcode[] array contains a pointer to
X | one of these handlers. The handlers in the
X | first group are in dishand.c; those in the
X | second group are in disfp.c.
X +---------------------------------------------
X */
X
extern void dfhand(), /* Default handler routine */
X sbhand(), /* Single-byte handler */
X aohand(), /* Arithmetic-op handler */
X sjhand(), /* Short-jump handler */
X imhand(), /* Immediate-operand handler */
X mvhand(), /* Simple move handler */
X mshand(), /* Segreg-move handler */
X pohand(), /* Pop memory/reg handler */
X cihand(), /* Intersegment call handler */
X mihand(), /* Immediate-move handler */
X mqhand(), /* Quick-move handler */
X tqhand(), /* Quick-test handler */
X rehand(), /* Return handler */
X mmhand(), /* Move-to-memory handler */
X srhand(), /* Shift and rotate handler */
X aahand(), /* ASCII-adjust handler */
X iohand(), /* Immediate port I/O handler */
X ljhand(), /* Long-jump handler */
X mahand(), /* Misc. arithmetic handler */
X mjhand(); /* Miscellaneous jump handler */
X
extern void eshand(), /* Bus-escape opcode handler */
X fphand(), /* Floating-point handler */
X inhand(); /* Interrupt-opcode handler */
X
extern char *REGS[]; /* Table of register names */
X
extern char *REGS0[]; /* Mode 0 register name table */
X
extern char *REGS1[]; /* Mode 1 register name table */
X
X#define AL REGS[0] /* CPU register manifests */
X#define CL REGS[1]
X#define DL REGS[2]
X#define BL REGS[3]
X#define AH REGS[4]
X#define CH REGS[5]
X#define DH REGS[6]
X#define BH REGS[7]
X#define AX REGS[8]
X#define CX REGS[9]
X#define DX REGS[10]
X#define BX REGS[11]
X#define SP REGS[12]
X#define BP REGS[13]
X#define SI REGS[14]
X#define DI REGS[15]
X#define ES REGS[16]
X#define CS REGS[17]
X#define SS REGS[18]
X#define DS REGS[19]
X#define BX_SI REGS0[0]
X#define BX_DI REGS0[1]
X#define BP_SI REGS0[2]
X#define BP_DI REGS0[3]
X
extern int symrank[6][6]; /* Symbol type/rank matrix */
X
extern unsigned long PC; /* Current program counter */
X
extern int segflg; /* Flag: segment override in effect */
X
extern int objflg; /* Flag: output object as a comment */
X
X#define OBJMAX 8 /* Size of the object code buffer */
X
extern unsigned char /* Internal buffer for object code */
X objbuf[OBJMAX];
X
extern void objini(), /* Object-buffer init routine */
X objout(); /* Object-code output routine */
X
extern int objptr; /* Index into the objbuf[] array */
X
extern void badseq(); /* Bad-code-sequence function */
X
extern char *getnam(); /* Symbol-name string function */
X
extern char *lookup(); /* Symbol-table lookup function */
X
extern int lookext(); /* Extern-definition lookup routine */
X
extern char *mtrans(); /* Interpreter for the mode byte */
X
extern void mtrunc(); /* Mode string truncator function */
X
extern char ADD[], /* Opcode family mnemonic strings */
X OR[],
X ADC[],
X SBB[],
X AND[],
X SUB[],
X XOR[],
X CMP[],
X NOT[],
X NEG[],
X MUL[],
X DIV[],
X MOV[],
X ESC[],
X TEST[],
X AMBIG[];
X
extern char *OPFAM[]; /* Indexed mnemonic family table */
X
extern struct exec HDR; /* Holds the object file's header */
X
X#define LOOK_ABS 0 /* Arguments to lookup() function */
X#define LOOK_REL 1
X#define LOOK_LNG 2
X
X#define TR_STD 0 /* Arguments to mtrans() function */
X#define TR_SEG 8
X
X /* Macro for byte input primitive */
X#define FETCH(p) \
X ++PC; p = getchar() & 0xff; objbuf[objptr++] = p
X
extern int close(); /* System file-close primitive */
extern int fprintf(); /* Library file-output function */
extern long lseek(); /* System file-position primitive */
extern int open(); /* System file-open primitive */
extern int printf(); /* Library output-format function */
extern int read(); /* System file-read primitive */
extern int sprintf(); /* Library string-output function */
extern char *strcat(); /* Library string-join function */
extern char *strcpy(); /* Library string-copy function */
extern int strlen(); /* Library string-length function */
X
X /* * * * * * * * * * * END OF dis.h * * * * * * * * * * */
X
X
END_OF_FILE
if test 7563 -ne `wc -c <'dis.h'`; then
echo shar: \"'dis.h'\" unpacked with wrong size!
fi
# end of 'dis.h'
fi
if test -f 'dis88.1' -a "${1}" != "-c" ; then
echo shar: Will not clobber existing file \"'dis88.1'\"
else
echo shar: Extracting \"'dis88.1'\" \(6174 characters\)
sed "s/^X//" >'dis88.1' <<'END_OF_FILE'
X.TH dis88 1 LOCAL
X.SH "NAME"
dis88 \- 8088 symbolic disassembler
X.SH "SYNOPSIS"
X\fBdis88\fP [ -o ] ifile [ ofile ]
X.SH "DESCRIPTION"
Dis88 reads ifile, which must be in PC/IX a.out format.
It interprets the binary opcodes and data locations, and
writes corresponding assembler source code to stdout, or
to ofile if specified. The program's output is in the
format of, and fully compatible with, the PC/IX assembler,
as(1). If a symbol table is present in ifile, labels and
references will be symbolic in the output. If the input
file lacks a symbol table, the fact will be noted, and the
disassembly will proceed, with the disassembler generating
synthetic labels as needed. If the input file has split
I/D space, or if it is executable, the disassembler will
make all necessary adjustments in address-reference calculations.
X.PP
If the "-o" option appears, object code will be included
in comments during disassembly of the text segment. This
feature is used primarily for debugging the disassembler
itself, but may provide information of passing interest
to users.
X.PP
The program always outputs the current machine address
before disassembling an opcode. If a symbol table is
present, this address is output as an assembler comment;
otherwise, it is incorporated into the synthetic label
which is generated internally. Since relative jumps,
especially short ones, may target unlabelled locations,
the program always outputs the physical target address
as a comment, to assist the user in following the code.
X.PP
The text segment of an object file is always padded to
an even machine address. In addition, if the file has
split I/D space, the text segment will be padded to a
paragraph boundary (i.e., an address divisible by 16).
As a result of this padding, the disassembler may produce
a few spurious, but harmless, instructions at the
end of the text segment.
X.PP
Disassembly of the data segment is a difficult matter.
The information to which initialized data refers cannot
be inferred from context, except in the special case
of an external data or address reference, which will be
reflected in the relocation table. Internal data and
address references will already be resolved in the object file,
and cannot be recreated. Therefore, the data
segment is disassembled as a byte stream, with long
stretches of null data represented by an appropriate
X".zerow" pseudo-op. This limitation notwithstanding,
labels (as opposed to symbolic references) are always
output at appropriate points within the data segment.
X.PP
If disassembly of the data segment is difficult, disassembly of the
bss segment is quite easy, because uninitialized data is all
zero by definition. No data
is output in the bss segment, but symbolic labels are
output as appropriate.
X.PP
XFor each opcode which takes an operand, a particular
symbol type (text, data, or bss) is appropriate. This
tidy correspondence is complicated somewhat, however,
by the existence of assembler symbolic constants and
segment override opcodes. Therefore, the disassembler's
symbol lookup routine attempts to apply a certain amount
of intelligence when it is asked to find a symbol. If
it cannot match on a symbol of the preferred type, it
may return a symbol of some other type, depending on
preassigned (and somewhat arbitrary) rankings within
each type. Finally, if all else fails, it returns a
string containing the address sought as a hex constant;
this behavior allows calling routines to use the output
of the lookup function regardless of the success of its
search.
X.PP
It is worth noting, at this point, that the symbol lookup
routine operates linearly, and has not been optimized in
any way. Execution time is thus likely to increase
geometrically with input file size. The disassembler is
internally limited to 1500 symbol table entries and 1500
relocation table entries; while these limits are generous
X(/unix, itself, has fewer than 800 symbols), they are not
guaranteed to be adequate in all cases. If the symbol
table or the relocation table overflows, the disassembly
aborts.
X.PP
XFinally, users should be aware of a bug in the assembler,
which causes it not to parse the "esc" mnemonic, even
though "esc" is a completely legitimate opcode which is
documented in all the Intel literature. To accommodate
this deficiency, the disassembler translates opcodes of
the "esc" family to .byte directives, but notes the
correct mnemonic in a comment for reference.
X.PP
In all cases, it should be possible to submit the output
of the disassembler program to the assembler, and assemble
it without error. In most cases, the resulting object
code will be identical to the original; in any event, it
will be functionally equivalent.
X.SH "SEE ALSO"
adb(1), as(1), cc(1), ld(1).
X.br
X"Assembler Reference Manual" in the PC/IX Programmer's
Guide.
X.SH "DIAGNOSTICS"
X"can't access input file" if the input file cannot be
found, opened, or read.
X.sp
X"can't open output file" if the output file cannot be
created.
X.sp
X"warning: host/cpu clash" if the program is run on a
machine with a different CPU.
X.sp
X"input file not in object format" if the magic number
does not correspond to that of a PC/IX object file.
X.sp
X"not an 8086/8088 object file" if the CPU ID of the
file header is incorrect.
X.sp
X"reloc table overflow" if there are more than 1500
entries in the relocation table.
X.sp
X"symbol table overflow" if there are more than 1500
entries in the symbol table.
X.sp
X"lseek error" if the input file is corrupted (should
never happen).
X.sp
X"warning: no symbols" if the symbol table is missing.
X.sp
X"can't reopen input file" if the input file is removed
or altered during program execution (should never happen).
X.SH "BUGS"
Numeric co-processor (i.e., 8087) mnemonics are not currently supported.
Instructions for the co-processor are
disassembled as CPU escape sequences, or as interrupts,
depending on how they were assembled in the first place.
X.sp
Despite the program's best efforts, a symbol retrieved
from the symbol table may sometimes be different from
the symbol used in the original assembly.
X.sp
The disassembler's internal tables are of fixed size,
and the program aborts if they overflow.
END_OF_FILE
if test 6174 -ne `wc -c <'dis88.1'`; then
echo shar: \"'dis88.1'\" unpacked with wrong size!
fi
# end of 'dis88.1'
fi
if test -f 'disfp.c' -a "${1}" != "-c" ; then
echo shar: Will not clobber existing file \"'disfp.c'\"
else
echo shar: Extracting \"'disfp.c'\" \(5589 characters\)
sed "s/^X//" >'disfp.c' <<'END_OF_FILE'
static char *sccsid =
X "@(#) disfp.c, Ver. 2.1 created 00:00:00 87/09/01";
X
X /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
X * *
X * Copyright (C) 1987 G. M. Harding, all rights reserved *
X * *
X * Permission to copy and redistribute is hereby granted, *
X * provided full source code, with all copyright notices, *
X * accompanies any redistribution. *
X * *
X * This file contains handler routines for the numeric op- *
X * codes of the 8087 co-processor, as well as a few other *
X * opcodes which are related to 8087 emulation. *
X * *
X * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
X
X#include "dis.h" /* Disassembler declarations */
X
X#define FPINT0 0xd8 /* Floating-point interrupts */
X#define FPINT1 0xd9
X#define FPINT2 0xda
X#define FPINT3 0xdb
X#define FPINT4 0xdc
X#define FPINT5 0xdd
X#define FPINT6 0xde
X#define FPINT7 0xdf
X
X /* Test for floating opcodes */
X#define ISFLOP(x) \
X (((x) >= FPINT0) && ((x) <= FPINT7))
X
X /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
X * *
X * This is the handler for the escape family of opcodes. *
X * These opcodes place the contents of a specified memory *
X * location on the system bus, for access by a peripheral *
X * or by a co-processor such as the 8087. (The 8087 NDP is *
X * accessed only via bus escapes.) Due to a bug in the *
X * PC/IX assembler, the "esc" mnemonic is not recognized; *
X * consequently, escape opcodes are disassembled as .byte *
X * directives, with the appropriate mnemonic and operand *
X * included as a comment. FOR NOW, those escape sequences *
X * corresponding to 8087 opcodes are treated as simple *
X * escapes. *
X * *
X * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
X
void
eshand(j)
X
X register int j; /* Pointer to optab[] entry */
X
X{/* * * * * * * * * * START OF eshand() * * * * * * * * * */
X
X register char *a;
X register int k;
X
X objini(j);
X
X FETCH(k);
X
X a = mtrans((j & 0xfd),(k & 0xc7),TR_STD);
X
X mtrunc(a);
X
X printf("\t.byte\t0x%02.2x\t\t| esc\t%s\n",j,a);
X
X for (k = 1; k < objptr; ++k)
X printf("\t.byte\t0x%02.2x\n",objbuf[k]);
X
X}/* * * * * * * * * * * END OF eshand() * * * * * * * * * * */
X
X /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
X * *
X * This is the handler routine for floating-point opcodes. *
X * Since PC/IX must accommodate systems with and without *
X * 8087 co-processors, it allows floating-point operations *
X * to be initiated in either of two ways: by a software *
X * interrput whose type is in the range 0xd8 through 0xdf, *
X * or by a CPU escape sequence, which is invoked by an op- *
X * code in the same range. In either case, the subsequent *
X * byte determines the actual numeric operation to be per- *
X * formed. However, depending on the method of access, *
X * either one or two code bytes will precede that byte, *
X * and the fphand() routine has no way of knowing whether *
X * it was invoked by interrupt or by an escape sequence. *
X * Therefore, unlike all of the other handler routines ex- *
X * cept dfhand(), fphand() does not initialize the object *
X * buffer, leaving that chore to the caller. *
X * *
X * FOR NOW, fphand() does not disassemble floating-point *
X * opcodes to floating mnemonics, but simply outputs the *
X * object code as .byte directives. *
X * *
X * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
X
void
fphand(j)
X
X register int j; /* Pointer to optab[] entry */
X
X{/* * * * * * * * * * START OF fphand() * * * * * * * * * */
X
X register int k;
X
X segflg = 0;
X
X FETCH(k);
X
X printf("\t.byte\t0x%02.2x\t\t| 8087 code sequence\n",
X objbuf[0]);
X
X for (k = 1; k < objptr; ++k)
X printf("\t.byte\t0x%02.2x\n",objbuf[k]);
X
X/* objout(); FOR NOW */
X
X}/* * * * * * * * * * * END OF fphand() * * * * * * * * * * */
X
X /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
X * *
X * This is the handler for variable software interrupt *
X * opcodes. It is included in this file because PC/IX im- *
X * plements its software floating-point emulation by means *
X * of interrupts. Any interrupt in the range 0xd8 through *
X * 0xdf is an NDP-emulation interrupt, and is specially *
X * handled by the assembler. *
X * *
X * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
X
void
inhand(j)
X
X register int j; /* Pointer to optab[] entry */
X
X{/* * * * * * * * * * START OF inhand() * * * * * * * * * */
X
X register int k;
X
X objini(j);
X
X FETCH(k);
X
X if (ISFLOP(k))
X {
X fphand(k);
X return;
X }
X
X printf("%s\t%d\n",optab[j].text,k);
X
X objout();
X
X}/* * * * * * * * * * * END OF inhand() * * * * * * * * * * */
X
X
END_OF_FILE
if test 5589 -ne `wc -c <'disfp.c'`; then
echo shar: \"'disfp.c'\" unpacked with wrong size!
fi
# end of 'disfp.c'
fi
if test -f 'dismain.c' -a "${1}" != "-c" ; then
echo shar: Will not clobber existing file \"'dismain.c'\"
else
echo shar: Extracting \"'dismain.c'\" \(17384 characters\)
sed "s/^X//" >'dismain.c' <<'END_OF_FILE'
static char *sccsid =
X "@(#) dismain.c, Ver. 2.1 created 00:00:00 87/09/01";
X
X /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
X * *
X * Copyright (C) 1987 G. M. Harding, all rights reserved *
X * *
X * Permission to copy and redistribute is hereby granted, *
X * provided full source code, with all copyright notices, *
X * accompanies any redistribution. *
X * *
X * This file contains the source code for the machine- *
X * independent portions of a disassembler program to run *
X * in a Unix (System III) environment. It expects, as its *
X * input, a file in standard a.out format, optionally con- *
X * taining symbol table information. If a symbol table is *
X * present, it will be used in the disassembly; otherwise, *
X * all address references will be literal (absolute). *
X * *
X * The disassembler program was originally written for an *
X * Intel 8088 CPU. However, all details of the actual CPU *
X * architecture are hidden in three machine-specific files *
X * named distabs.c, dishand.c, and disfp.c (the latter *
X * file is specific to the 8087 numeric co-processor). The *
X * code in this file is generic, and should require mini- *
X * mal revision if a different CPU is to be targeted. If a *
X * different version of Unix is to be targeted, changes to *
X * this file may be necessary, and if a completely differ- *
X * ent OS is to be targeted, all bets are off. *
X * *
X * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
X
X#include "dis.h" /* Disassembler declarations */
X
extern char *release; /* Contains release string */
X
static char *IFILE = NULL; /* Points to input file name */
X
static char *OFILE = NULL; /* Points to output file name */
X
static char *PRG; /* Name of invoking program */
X
static unsigned long zcount; /* Consecutive "0" byte count */
X
int objflg = 0; /* Flag: output object bytes */
X
X#if unix && i8086 && ibmpc /* Set the CPU identifier */
static int cpuid = 1;
X#else
static int cpuid = 0;
X#endif
X
X /* * * * * * * MISCELLANEOUS UTILITY FUNCTIONS * * * * * * */
X
static void
usage(s)
X register char *s;
X{
X fprintf(stderr,"\07usage: %s [-o] ifile [ofile]\n",s);
X exit(-1);
X}
X
static void
fatal(s,t)
X register char *s, *t;
X{
X fprintf(stderr,"\07%s: %s\n",s,t);
X exit(-1);
X}
X
static void
zdump(beg)
X unsigned long beg;
X{
X beg = PC - beg;
X if (beg > 1L)
X printf("\t.zerow\t%ld\n",(beg >> 1));
X if (beg & 1L)
X printf("\t.byte\t0\n");
X}
X
static char *
invoker(s)
X register char *s;
X{
X extern int strlen();
X register int k;
X
X k = strlen(s);
X
X while (k--)
X if (s[k] == '/')
X {
X s += k;
X ++s;
X break;
X }
X
X return (s);
X}
X
X /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
X * *
X * This rather tricky routine supports the disdata() func- *
X * tion. Its job is to output the code for a sequence of *
X * data bytes whenever the object buffer is full, or when *
X * a symbolic label is to be output. However, it must also *
X * keep track of consecutive zero words so that lengthy *
X * stretches of null data can be compressed by the use of *
X * an appropriate assembler pseudo-op. It does this by *
X * setting and testing a file-wide flag which counts suc- *
X * cessive full buffers of null data. The function returns *
X * a logical TRUE value if it outputs anything, logical *
X * FALSE otherwise. (This enables disdata() to determine *
X * whether to output a new synthetic label when there is *
X * no symbol table.) *
X * *
X * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
X
static int
objdump(c)
X
X register char *c;
X
X{/* * * * * * * * * * START OF objdump() * * * * * * * * * */
X
X register int k;
X int retval = 0;
X
X if (objptr == OBJMAX)
X {
X for (k = 0; k < OBJMAX; ++k)
X if (objbuf[k])
X break;
X if (k == OBJMAX)
X {
X zcount += k;
X objptr = 0;
X if (c == NULL)
X return (retval);
X }
X }
X
X if (zcount)
X {
X printf("\t.zerow\t%ld\n",(zcount >> 1));
X ++retval;
X zcount = 0L;
X }
X
X if (objptr)
X {
X printf("\t.byte\t");
X ++retval;
X }
X else
X return (retval);
X
X for (k = 0; k < objptr; ++k)
X {
X printf("0x%02.2x",objbuf[k]);
X if (k < (objptr - 1))
X putchar(',');
X else
X putchar('\n');
X }
X
X objptr = 0;
X
X return (retval);
X
X}/* * * * * * * * * * END OF objdump() * * * * * * * * * */
X
X /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
X * *
X * This routine, called at the beginning of the input *
X * cycle for each object byte, and before any interpreta- *
X * tion is attempted, searches the symbol table for any *
X * symbolic name with a value corresponding to the cur- *
X * rent PC and a type corresponding to the segment type *
X * (i.e., text, data, or bss) specified by the function's *
X * argument. If any such name is found, a pointer to it is *
X * returned; otherwise, a NULL pointer is returned. *
X * *
X * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
X
static char *
getlab(type)
X
X register int type;
X
X{/* * * * * * * * * * START OF getlab() * * * * * * * * * */
X
X register int k;
X static char b[32], c[10];
X
X if (symptr < 0)
X if ((type == N_TEXT)
X || ((type == N_DATA) && ( ! objptr ) && ( ! zcount )))
X {
X if (type == N_TEXT)
X sprintf(b,"T%05.5lx:",PC);
X else
X sprintf(b,"D%05.5lx:",PC);
X return (b);
X }
X else
X return (NULL);
X
X for (k = 0; k <= symptr; ++k)
X if ((symtab[k].n_value == PC)
X && ((symtab[k].n_sclass & N_SECT) == type))
X {
X sprintf(b,"%s:\n",getnam(k));
X if (objflg && (type != N_TEXT))
X sprintf(c,"| %05.5lx\n",PC);
X strcat(b,c);
X return (b);
X }
X
X return (NULL);
X
X}/* * * * * * * * * * * END OF getlab() * * * * * * * * * * */
X
X /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
X * *
X * This routine performs a preliminary scan of the symbol *
X * table, before disassembly begins, and outputs declara- *
X * tions of globals and constants. *
X * *
X * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
X
static void
prolog()
X
X{/* * * * * * * * * * START OF prolog() * * * * * * * * * */
X
X register int j, flag;
X
X if (symptr < 0)
X return;
X
X for (j = flag = 0; j <= symptr; ++j)
X if ((symtab[j].n_sclass & N_CLASS) == C_EXT)
X if (((symtab[j].n_sclass & N_SECT) > N_UNDF)
X && ((symtab[j].n_sclass & N_SECT) < N_COMM))
X {
X char *c = getnam(j);
X printf("\t.globl\t%s",c);
X if (++flag == 1)
X {
X putchar('\t');
X if (strlen(c) < 8)
X putchar('\t');
X printf("| Internal global\n");
X }
X else
X putchar('\n');
X }
X else
X if (symtab[j].n_value)
X {
X char *c = getnam(j);
X printf("\t.comm\t%s,0x%08.8lx",c,
X symtab[j].n_value);
X if (++flag == 1)
X printf("\t| Internal global\n");
X else
X putchar('\n');
X }
X
X if (flag)
X putchar('\n');
X
X for (j = flag = 0; j <= relptr; ++j)
X if (relo[j].r_symndx < S_BSS)
X {
X char *c = getnam(relo[j].r_symndx);
X ++flag;
X printf("\t.globl\t%s",c);
X putchar('\t');
X if (strlen(c) < 8)
X putchar('\t');
X printf("| Undef: %05.5lx\n",relo[j].r_vaddr);
X }
X
X if (flag)
X putchar('\n');
X
X for (j = flag = 0; j <= symptr; ++j)
X if ((symtab[j].n_sclass & N_SECT) == N_ABS)
X {
X char *c = getnam(j);
X printf("%s=0x%08.8lx",c,symtab[j].n_value);
X if (++flag == 1)
X {
X printf("\t\t");
X if (strlen(c) < 5)
X putchar('\t');
X printf("| Literal\n");
X }
X else
X putchar('\n');
X }
X
X if (flag)
X putchar('\n');
X
X}/* * * * * * * * * * * END OF prolog() * * * * * * * * * * */
X
X /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
X * *
X * This function is responsible for disassembly of the *
X * object file's text segment. *
X * *
X * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
X
static void
distext()
X
X{/* * * * * * * * * * START OF distext() * * * * * * * * * */
X
X char *c;
X register int j;
X register void (*f)();
X
X for (j = 0; j < (int)(HDR.a_hdrlen); ++j)
X getchar();
X
X printf("| %s, %s\n\n",PRG,release);
X
X printf("| @(");
X
X printf("#)\tDisassembly of %s",IFILE);
X
X if (symptr < 0)
X printf(" (no symbols)\n\n");
X else
X printf("\n\n");
X
X if (HDR.a_flags & A_EXEC)
X printf("| File is executable\n\n");
X
X if (HDR.a_flags & A_SEP)
X {
X printf("| File has split I/D space, and may have\n");
X printf("| extraneous instructions in text segment\n\n");
X }
X
X prolog();
X
X printf("\t.text\t\t\t| loc = %05.5lx, size = %05.5lx\n\n",
X PC,HDR.a_text);
X
X segflg = 0;
X
X for (PC = 0L; PC < HDR.a_text; ++PC)
X {
X j = getchar() & 0xff;
X if ((j == 0) && ((PC + 1L) == HDR.a_text))
X {
X ++PC;
X break;
X }
X if ((c = getlab(N_TEXT)) != NULL)
X printf("%s",c);
X f = optab[j].func;
X (*f)(j);
X }
X
X}/* * * * * * * * * * END OF distext() * * * * * * * * * */
X
X /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
X * *
X * This function handles the object file's data segment. *
X * There is no good way to disassemble a data segment, be- *
X * cause it is impossible to tell, from the object code *
X * alone, what each data byte refers to. If it refers to *
X * an external symbol, the reference can be resolved from *
X * the relocation table, if there is one. However, if it *
X * refers to a static symbol, it cannot be distinguished *
X * from numeric, character, or other pointer data. In some *
X * cases, one might make a semi-educated guess as to the *
X * nature of the data, but such guesses are inherently *
X * haphazard, and they are bound to be wrong a good por- *
X * tion of the time. Consequently, the data segment is *
X * disassembled as a byte stream, which will satisfy no *
X * one but which, at least, will never mislead anyone. *
X * *
X * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
X
static void
disdata()
X
X{/* * * * * * * * * * START OF disdata() * * * * * * * * * */
X
X register char *c;
X register int j;
X unsigned long end;
X
X putchar('\n');
X
X if (HDR.a_flags & A_SEP)
X {
X PC = 0L;
X end = HDR.a_data;
X }
X else
X end = HDR.a_text + HDR.a_data;
X
X printf("\t.data\t\t\t| loc = %05.5lx, size = %05.5lx\n\n",
X PC,HDR.a_data);
X
X segflg = 0;
X
X for (objptr = 0, zcount = 0L; PC < end; ++PC)
X {
X if ((c = getlab(N_DATA)) != NULL)
X {
X objdump(c);
X printf("%s",c);
X }
X if (objptr >= OBJMAX)
X if (objdump(NULL) && (symptr < 0))
X printf("D%05.5lx:",PC);
X j = getchar() & 0xff;
X objbuf[objptr++] = j;
X }
X
X objdump("");
X
X}/* * * * * * * * * * END OF disdata() * * * * * * * * * */
X
X /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
X * *
X * This function handles the object file's bss segment. *
X * Disassembly of the bss segment is easy, because every- *
X * thing in it is zero by definition. *
X * *
X * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
X
static void
disbss()
X
X{/* * * * * * * * * * START OF disbss() * * * * * * * * * */
X
X register int j;
X register char *c;
X unsigned long beg, end;
X
X putchar('\n');
X
X if (HDR.a_flags & A_SEP)
X end = HDR.a_data + HDR.a_bss;
X else
X end = HDR.a_text + HDR.a_data + HDR.a_bss;
X
X printf("\t.bss\t\t\t| loc = %05.5lx, size = %05.5lx\n\n",
X PC,HDR.a_bss);
X
X segflg = 0;
X
X for (beg = PC; PC < end; ++PC)
X if ((c = getlab(N_BSS)) != NULL)
X {
X if (PC > beg)
X {
X zdump(beg);
X beg = PC;
X }
X printf("%s",c);
X }
X
X if (PC > beg)
X zdump(beg);
X
X}/* * * * * * * * * * * END OF disbss() * * * * * * * * * * */
X
X /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
X * *
X * This is the program entry point. The command line is *
X * searched for an input file name, which must be present. *
X * An optional output file name is also permitted; if none *
X * is found, standard output is the default. One command- *
X * line option is available: "-o", which causes the pro- *
X * gram to include object code in comments along with its *
X * mnemonic output. *
X * *
X * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
X
void
main(argc,argv)
X
X int argc; /* Command-line args from OS */
X register char **argv;
X
X{/* * * * * * * * * * * START OF main() * * * * * * * * * * */
X
X char a[1024];
X register int fd;
X long taboff, tabnum;
X long reloff, relnum;
X
X PRG = invoker(*argv);
X
X while (*++argv != NULL) /* Process command-line args */
X if (**argv == '-')
X switch (*++*argv)
X {
X case 'o' :
X if (*++*argv)
X usage(PRG);
X else
X ++objflg;
X break;
X default :
X usage(PRG);
X }
X else
X if (IFILE == NULL)
X IFILE = *argv;
X else if (OFILE == NULL)
X OFILE = *argv;
X else
X usage(PRG);
X
X if (IFILE == NULL)
X usage(PRG);
X else
X if ((fd = open(IFILE,O_RDONLY)) < 0)
X {
X sprintf(a,"can't access input file %s",IFILE);
X fatal(PRG,a);
X }
X
X if (OFILE != NULL)
X if (freopen(OFILE,"w",stdout) == NULL)
X {
X sprintf(a,"can't open output file %s",OFILE);
X fatal(PRG,a);
X }
X
X if ( ! cpuid )
X fprintf(stderr,"\07%s: warning: host/cpu clash\n",PRG);
X
X read(fd,&HDR,sizeof(struct exec));
X
X if (BADMAG(HDR))
X {
X sprintf(a,"input file %s not in object format",IFILE);
X fatal(PRG,a);
X }
X
X if (HDR.a_cpu != A_I8086)
X {
X sprintf(a,"%s is not an 8086/8088 object file",IFILE);
X fatal(PRG,a);
X }
X
X if (HDR.a_hdrlen <= A_MINHDR)
X HDR.a_trsize = HDR.a_drsize =
X HDR.a_tbase = HDR.a_dbase =
X HDR.a_lnums = HDR.a_toffs = 0L;
X
X reloff = HDR.a_text /* Compute reloc data offset */
X + HDR.a_data
X + (long)(HDR.a_hdrlen);
X
X relnum =
X (HDR.a_trsize + HDR.a_drsize) / sizeof(struct reloc);
X
X taboff = reloff /* Compute name table offset */
X + HDR.a_trsize
X + HDR.a_drsize;
X
X tabnum = HDR.a_syms / sizeof(struct nlist);
X
X if (relnum > MAXSYM)
X fatal(PRG,"reloc table overflow");
X
X if (tabnum > MAXSYM)
X fatal(PRG,"symbol table overflow");
X
X if (relnum) /* Get reloc data */
X if (lseek(fd,reloff,0) != reloff)
X fatal(PRG,"lseek error");
X else
X {
X for (relptr = 0; relptr < relnum; ++relptr)
X read(fd,&relo[relptr],sizeof(struct reloc));
X relptr--;
X }
X
X if (tabnum) /* Read in symtab */
X if (lseek(fd,taboff,0) != taboff)
X fatal(PRG,"lseek error");
X else
X {
X for (symptr = 0; symptr < tabnum; ++symptr)
X read(fd,&symtab[symptr],sizeof(struct nlist));
X symptr--;
X }
X else
X fprintf(stderr,"\07%s: warning: no symbols\n",PRG);
X
X close(fd);
X
X if (freopen(IFILE,"r",stdin) == NULL)
X {
X sprintf(a,"can't reopen input file %s",IFILE);
X fatal(PRG,a);
X }
X
X distext();
X
X disdata();
X
X disbss();
X
X exit(0);
X
X}/* * * * * * * * * * * END OF main() * * * * * * * * * * */
X
X
END_OF_FILE
if test 17384 -ne `wc -c <'dismain.c'`; then
echo shar: \"'dismain.c'\" unpacked with wrong size!
fi
# end of 'dismain.c'
fi
if test -f 'disrel.c' -a "${1}" != "-c" ; then
echo shar: Will not clobber existing file \"'disrel.c'\"
else
echo shar: Extracting \"'disrel.c'\" \(742 characters\)
sed "s/^X//" >'disrel.c' <<'END_OF_FILE'
static char *copyright =
X "@(#) Copyright (C) 1987 G. M. Harding, all rights reserved";
X
static char *sccsid =
X "@(#) disrel.c, Ver. 2.1 created 00:00:00 87/09/01";
X
char *release =
X "release 2.1 (PC/IX)";
X
X /*
X **
X ** This file documents the major revisions to the 8088 sym-
X ** bolic disassembler. It also contains the release string
X ** which is output at the head of each disassembly, and the
X ** copyright string which must be incorporated in any code
X ** distribution.
X **
X ** Permission to copy and redistribute is hereby granted,
X ** provided full source code, with all copyright notices,
X ** accompanies any redistribution.
X **
X ** REVISION HISTORY:
X **
X ** SEP 87:
X ** After internal shakeout, released on Usenet.
X **
X */
X
END_OF_FILE
if test 742 -ne `wc -c <'disrel.c'`; then
echo shar: \"'disrel.c'\" unpacked with wrong size!
fi
# end of 'disrel.c'
fi
echo shar: End of archive 1 \(of 2\).
cp /dev/null ark1isdone
MISSING=""
for I in 1 2 ; do
if test ! -f ark${I}isdone ; then
MISSING="${MISSING} ${I}"
fi
done
if test "${MISSING}" = "" ; then
echo You have unpacked both archives.
rm -f ark[1-9]isdone
else
echo You still need to unpack the following archives:
echo " " ${MISSING}
fi
## End of shell archive.
exit 0
--
Please send comp.sources.unix-related mail to rsalz@uunet.uu.net.