Beginning to be useful as a disassembler again

This commit is contained in:
Pierre Pronchery 2011-04-23 06:09:06 +00:00
parent 4bd2f1c684
commit 91ecd5ab54
15 changed files with 617 additions and 12 deletions

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@ -40,6 +40,7 @@ dist:
$(PACKAGE)-$(VERSION)/src/parser.c \
$(PACKAGE)-$(VERSION)/src/token.c \
$(PACKAGE)-$(VERSION)/src/main.c \
$(PACKAGE)-$(VERSION)/src/deasm.c \
$(PACKAGE)-$(VERSION)/src/Makefile \
$(PACKAGE)-$(VERSION)/src/arch.h \
$(PACKAGE)-$(VERSION)/src/asm.h \

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@ -179,6 +179,8 @@ typedef struct _ArchPluginHelper
/* callbacks */
/* accessors */
char const * (*get_filename)(Arch * arch);
ArchInstruction * (*get_instruction_by_opcode)(Arch * arch,
uint8_t size, uint32_t opcode);
ArchRegister * (*get_register_by_name_size)(Arch * arch,
char const * name, uint32_t size);

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@ -1,2 +1,3 @@
.cvsignore
asm
deasm

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@ -1,5 +1,5 @@
SUBDIRS = arch format
TARGETS = libasm.a libasm.so asm
TARGETS = libasm.a libasm.so asm deasm
PREFIX = /usr/local
DESTDIR =
LIBDIR = $(PREFIX)/lib
@ -42,6 +42,13 @@ asm_LDFLAGS = $(LDFLAGSF) $(LDFLAGS) -L. -Wl,-rpath,$(LIBDIR) -lasm
asm: $(asm_OBJS) libasm.so
$(CC) -o asm $(asm_OBJS) $(asm_LDFLAGS)
deasm_OBJS = deasm.o
deasm_CFLAGS = $(CPPFLAGSF) $(CPPFLAGS) $(CFLAGSF) $(CFLAGS)
deasm_LDFLAGS = $(LDFLAGSF) $(LDFLAGS) -L. -Wl,-rpath,$(LIBDIR) -lasm
deasm: $(deasm_OBJS) libasm.so
$(CC) -o deasm $(deasm_OBJS) $(deasm_LDFLAGS)
arch.o: arch.c arch.h ../config.h
$(CC) $(libasm_CFLAGS) -c arch.c
@ -63,13 +70,16 @@ token.o: token.c token.h
main.o: main.c ../include/Asm.h
$(CC) $(asm_CFLAGS) -c main.c
deasm.o: deasm.c ../include/Asm.h
$(CC) $(deasm_CFLAGS) -c deasm.c
clean:
@for i in $(SUBDIRS); do (cd $$i && $(MAKE) clean) || exit; done
$(RM) -- $(libasm_OBJS) $(asm_OBJS)
$(RM) -- $(libasm_OBJS) $(asm_OBJS) $(deasm_OBJS)
distclean:
@for i in $(SUBDIRS); do (cd $$i && $(MAKE) distclean) || exit; done
$(RM) -- $(libasm_OBJS) $(asm_OBJS)
$(RM) -- $(libasm_OBJS) $(asm_OBJS) $(deasm_OBJS)
$(RM) -- $(TARGETS)
install: $(TARGETS)
@ -81,6 +91,8 @@ install: $(TARGETS)
$(LN) -s -- libasm.so.0.0 $(DESTDIR)$(LIBDIR)/libasm.so
$(MKDIR) $(DESTDIR)$(BINDIR)
$(INSTALL) -m 0755 -- asm $(DESTDIR)$(BINDIR)/asm
$(MKDIR) $(DESTDIR)$(BINDIR)
$(INSTALL) -m 0755 -- deasm $(DESTDIR)$(BINDIR)/deasm
uninstall:
@for i in $(SUBDIRS); do (cd $$i && $(MAKE) uninstall) || exit; done
@ -89,5 +101,6 @@ uninstall:
$(RM) -- $(DESTDIR)$(LIBDIR)/libasm.so.0
$(RM) -- $(DESTDIR)$(LIBDIR)/libasm.so
$(RM) -- $(DESTDIR)$(BINDIR)/asm
$(RM) -- $(DESTDIR)$(BINDIR)/deasm
.PHONY: all subdirs clean distclean install uninstall

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@ -172,7 +172,7 @@ ArchInstruction * arch_get_instruction_by_opcode(Arch * arch, uint8_t size,
for(i = 0; i < arch->instructions_cnt; i++)
{
ai = &arch->plugin->instructions[i];
if(AO_GET_SIZE(ai->opcode) != size)
if(AO_GET_SIZE(ai->flags) != size)
continue;
if(ai->opcode == opcode)
return ai;
@ -457,6 +457,9 @@ static void _decode_print(ArchInstructionCall * call)
/* arch_exit */
int arch_exit(Arch * arch)
{
#ifdef DEBUG
fprintf(stderr, "DEBUG: %s()\n", __func__);
#endif
arch->filename = NULL;
arch->fp = NULL;
arch->buffer = NULL;
@ -478,6 +481,7 @@ int arch_init(Arch * arch, char const * filename, FILE * fp)
arch->fp = fp;
arch->helper.arch = arch;
arch->helper.get_filename = _arch_get_filename;
arch->helper.get_instruction_by_opcode = arch_get_instruction_by_opcode;
arch->helper.get_register_by_name_size = arch_get_register_by_name_size;
arch->helper.read = NULL;
arch->helper.write = _arch_write;
@ -498,6 +502,7 @@ int arch_init_buffer(Arch * arch, char const * buffer, size_t size)
arch->buffer_pos = 0;
arch->helper.arch = arch;
arch->helper.get_filename = _arch_get_filename;
arch->helper.get_instruction_by_opcode = arch_get_instruction_by_opcode;
arch->helper.get_register_by_name_size = arch_get_register_by_name_size;
arch->helper.write = NULL;
arch->helper.read = _arch_read_buffer;
@ -531,6 +536,11 @@ static ssize_t _arch_read_buffer(Arch * arch, void * buf, size_t size)
{
ssize_t s = min(arch->buffer_cnt - arch->buffer_pos, size);
#ifdef DEBUG
fprintf(stderr, "DEBUG: %s()\n", __func__);
#endif
if(s == 0)
return -error_set_code(1, "%s", "End of buffer reached");
memcpy(buf, &arch->buffer[arch->buffer_pos], s);
arch->buffer_pos += s;
return s;

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@ -80,5 +80,5 @@ ArchPlugin arch_plugin =
_amd64_registers,
_amd64_instructions,
_i386_write,
NULL
_i386_decode
};

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@ -74,5 +74,5 @@ ArchPlugin arch_plugin =
_i386_registers,
_i386_instructions,
_i386_write,
NULL
_i386_decode
};

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@ -23,11 +23,33 @@
/* i386 */
/* private */
/* prototypes */
static int _i386_decode(ArchPlugin * plugin, ArchInstructionCall * call);
static int _i386_write(ArchPlugin * plugin, ArchInstruction * instruction,
ArchInstructionCall * call);
/* functions */
/* i386_decode */
static int _i386_decode(ArchPlugin * plugin, ArchInstructionCall * call)
{
ArchPluginHelper * helper = plugin->helper;
ArchInstruction * ai = NULL;
uint8_t opcode;
/* FIXME really implement */
if(helper->read(helper->arch, &opcode, sizeof(opcode))
!= sizeof(opcode))
return -1;
if((ai = helper->get_instruction_by_opcode(helper->arch, 8, opcode))
== NULL)
/* FIXME return "db" instead */
return -1;
call->name = ai->name;
return 0;
}
/* i386_write */
static int _write_constant(ArchPlugin * plugin,
ArchOperandDefinition definition, ArchOperand * operand);
static int _write_dregister(ArchPlugin * plugin, uint32_t * i,

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@ -75,5 +75,5 @@ ArchPlugin arch_plugin =
_i386_real_registers,
_i386_real_instructions,
_i386_write,
NULL
_i386_decode
};

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@ -75,5 +75,5 @@ ArchPlugin arch_plugin =
_i486_registers,
_i486_instructions,
_i386_write,
NULL
_i386_decode
};

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@ -76,5 +76,5 @@ ArchPlugin arch_plugin =
_i586_registers,
_i586_instructions,
_i386_write,
NULL
_i386_decode
};

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@ -78,5 +78,5 @@ ArchPlugin arch_plugin =
_i686_registers,
_i686_instructions,
_i386_write,
NULL
_i386_decode
};

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@ -89,7 +89,6 @@ As * as_new(char const * arch, char const * format)
{
As * as;
/* FIXME add signatures to the format plug-in (for disas too) */
if((as = object_new(sizeof(*as))) == NULL)
return NULL;
if(arch == NULL)

547
src/deasm.c Normal file
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@ -0,0 +1,547 @@
/* $Id$ */
/* Copyright (c) 2011 Pierre Pronchery <khorben@defora.org> */
/* This file is part of DeforaOS Devel asm */
/* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, version 3 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include <System.h>
#include <dirent.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include "Asm.h"
#include "../config.h"
/* constants */
#ifndef PREFIX
# define PREFIX "/usr/local"
#endif
#ifndef LIBDIR
# define LIBDIR PREFIX "/lib"
#endif
/* macros */
#define max(a, b) ((a) > (b) ? (a) : (b))
/* deasm */
/* private */
/* types */
typedef struct _DeasmFormat
{
Plugin * plugin;
FormatPlugin * format;
} DeasmFormat;
/* XXX ugly */
#define _Deasm _Format
typedef struct _Deasm
{
char const * arch;
As * as;
FormatPluginHelper helper;
DeasmFormat * format;
size_t format_cnt;
char const * filename;
FILE * fp;
} Deasm;
/* prototypes */
static int _deasm(char const * arch, char const * format,
char const * filename);
static int _deasm_buffer(char const * arch, char const * format,
char const * buffer, size_t size);
static int _deasm_error(char const * message, int ret);
static int _deasm_string(char const * arch, char const * format,
char const * string);
static int _deasm_list(void);
/* helper */
static int _deasm_helper_decode(Format * format, char const * section,
off_t offset, size_t size, off_t base);
static ssize_t _deasm_helper_read(Format * format, void * buf, size_t size);
static off_t _deasm_helper_seek(Format * format, off_t offset, int whence);
/* format */
static DeasmFormat const * _deasm_format_open(Deasm * deasm,
char const * format);
static int _deasm_format_open_all(Deasm * deasm);
static char const * _deasm_format_detect(DeasmFormat const * format);
static void _deasm_format_close(DeasmFormat const * format);
static void _deasm_format_close_all(Deasm * deasm);
static int _usage(void);
/* functions */
/* deasm */
static int _deasm_do_format(Deasm * deasm, char const * format);
static int _deasm_do(Deasm * deasm);
static int _deasm_do_callback(Deasm * deasm, FormatPlugin * format);
#if 0
static int _deasm_format_decode(Format * format, char const * section,
off_t offset, size_t size, off_t base);
#endif
static int _deasm(char const * arch, char const * format,
char const * filename)
{
int ret = 1;
Deasm deasm;
deasm.arch = arch;
deasm.as = NULL;
deasm.helper.format = &deasm;
deasm.helper.read = _deasm_helper_read;
deasm.helper.seek = _deasm_helper_seek;
deasm.helper.write = NULL;
deasm.helper.decode = _deasm_helper_decode;
deasm.format = NULL;
deasm.format_cnt = 0;
if((deasm.fp = fopen(filename, "r")) == NULL)
return -_deasm_error(filename, 1);
deasm.filename = filename;
if(format != NULL)
ret = _deasm_do_format(&deasm, format);
else
ret = _deasm_do(&deasm);
if(deasm.as != NULL)
as_delete(deasm.as);
fclose(deasm.fp);
_deasm_format_close_all(&deasm);
if(ret != 0)
error_print("deasm");
return ret;
}
static int _deasm_do_format(Deasm * deasm, char const * format)
{
int ret;
size_t i;
DeasmFormat const * df;
#ifdef DEBUG
fprintf(stderr, "DEBUG: %s(\"%s\")\n", __func__, format);
#endif
/* check if the plug-in is already opened */
for(i = 0; i < deasm->format_cnt; i++)
if(strcmp(deasm->format[i].format->name, format) == 0)
break;
if(i < deasm->format_cnt)
df = &deasm->format[i];
else if((df = _deasm_format_open(deasm, format)) == NULL)
return -1;
/* disassemble */
ret = _deasm_do_callback(deasm, df->format);
return ret;
}
static int _deasm_do(Deasm * deasm)
{
int ret = 1;
size_t i;
size_t s = 0;
char * buf;
FormatPlugin * format;
#ifdef DEBUG
fprintf(stderr, "DEBUG: %s()\n", __func__);
#endif
_deasm_format_open_all(deasm);
for(i = 0; i < deasm->format_cnt; i++)
s = max(s, deasm->format[i].format->signature_len);
if((buf = malloc(s)) == NULL)
return -_deasm_error(deasm->filename, 1);
if(fread(buf, 1, s, deasm->fp) != s)
{
if(ferror(deasm->fp))
ret = -_deasm_error(deasm->filename, 1);
else
ret = _deasm_do_format(deasm, "flat");
}
else
{
for(i = 0; i < deasm->format_cnt; i++)
{
format = deasm->format[i].format;
if(format->signature_len == 0)
continue;
if(memcmp(format->signature, buf, format->signature_len)
!= 0)
continue;
if(deasm->arch == NULL)
deasm->arch = _deasm_format_detect(
&deasm->format[i]);
if(deasm->arch == NULL)
continue;
ret = _deasm_do_callback(deasm, format);
break;
}
if(i == deasm->format_cnt)
ret = _deasm_do_format(deasm, "flat");
}
free(buf);
return ret;
}
static int _deasm_do_callback(Deasm * deasm, FormatPlugin * format)
{
int ret;
#ifdef DEBUG
fprintf(stderr, "DEBUG: %s(\"%s\")\n", __func__, format->name);
#endif
if(deasm->arch == NULL)
{
if(format->detect == NULL)
return -error_set_code(1, "%s: %s", format->name,
"Unable to detect the architecture");
if((deasm->arch = format->detect(format)) == NULL)
return -1;
}
if((deasm->as = as_new(deasm->arch, format->name)) == NULL)
return -error_print("deasm");
printf("\n%s: %s-%s\n", deasm->filename, format->name,
as_get_arch_name(deasm->as));
ret = format->decode(format);
return ret;
}
/* deasm_buffer */
static int _deasm_buffer(char const * arch, char const * format,
char const * buffer, size_t size)
{
As * as;
#ifdef DEBUG
fprintf(stderr, "DEBUG: %s()\n", __func__);
#endif
if((as = as_new(arch, format)) == NULL)
return -1;
if(as_decode(as, buffer, size) != 0)
error_print("deasm");
as_delete(as);
return 0;
}
/* deasm_error */
static int _deasm_error(char const * message, int ret)
{
fputs("deasm: ", stderr);
perror(message);
return ret;
}
/* deasm_string */
static int _string_hex2bin(int c);
static int _string_ishex(int c);
static int _deasm_string(char const * arch, char const * format,
char const * string)
{
int ret;
unsigned char * str = (unsigned char *)string;
size_t len = strlen(string);
char * s;
size_t i;
size_t j;
#ifdef DEBUG
fprintf(stderr, "DEBUG: %s(\"%s\", \"%s\", \"%s\")\n", __func__, arch,
format, string);
#endif
if((s = malloc(len + 1)) == NULL)
return -error_set_print("deasm", 1, "%s", strerror(errno));
for(i = 0, j = 0; i < len; i++)
{
if(str[i] != '\\')
s[j++] = str[i];
else if(str[i + 1] != 'x') /* "\\" */
s[j++] = str[++i];
else if(i + 3 < len && _string_ishex(str[i + 2])
&& _string_ishex(str[i + 3])) /* "\xHH" */
{
s[j++] = (_string_hex2bin(str[i + 2]) << 4)
| _string_hex2bin(str[i + 3]);
i += 3;
}
}
s[j] = '\0'; /* not really necessary */
ret = _deasm_buffer(arch, format, s, j);
free(s);
return ret;
}
static int _string_hex2bin(int c)
{
if(c >= '0' && c <= '9')
return c - '0';
if(c >= 'a' && c <= 'f')
return c - 'a' + 10;
if(c >= 'A' && c <= 'F')
return c - 'A' + 10;
return -1;
}
static int _string_ishex(int c)
{
return (c >= '0' && c <= '9') || (c >= 'a' && c <= 'f')
|| (c >= 'A' || c <= 'F');
}
/* deasm_list */
static int _deasm_list(void)
{
Deasm deasm;
size_t i;
char const * sep = "";
#ifdef DEBUG
fprintf(stderr, "DEBUG: %s()\n", __func__);
#endif
memset(&deasm, 0, sizeof(deasm));
as_plugin_list(ASPT_ARCH);
_deasm_format_open_all(&deasm);
fputs("\nAvailable format plug-ins:\n", stderr);
for(i = 0; i < deasm.format_cnt; i++)
{
if(deasm.format[i].format->decode == NULL)
continue;
fprintf(stderr, "%s%s", sep, deasm.format[i].format->name);
sep = ", ";
}
fputc('\n', stderr);
_deasm_format_close_all(&deasm);
return 0;
}
/* helper */
/* deasm_helper_decode */
static int _deasm_helper_decode(Format * format, char const * section,
off_t offset, size_t size, off_t base)
{
if(section != NULL)
printf("\n%s%s:\n", "Disassembly of section ", section);
if(fseek(format->fp, offset, SEEK_SET) != 0)
return -error_set_code(1, "%s: %s", format->filename,
strerror(errno));
printf("\n%08lx:\n", (unsigned long)offset + base);
/* FIXME implement */
if(fseek(format->fp, offset + size, SEEK_SET) != 0)
return -error_set_code(1, "%s: %s", format->filename,
strerror(errno));
return 0;
}
/* deasm_helper_read */
static ssize_t _deasm_helper_read(Format * format, void * buf, size_t size)
{
if(fread(buf, size, 1, format->fp) == 1)
return size;
return -error_set_code(1, "%s: %s", format->filename, strerror(errno));
}
/* deasm_helper_seek */
static off_t _deasm_helper_seek(Format * format, off_t offset, int whence)
{
if(fseek(format->fp, offset, whence) != 0)
return -error_set_code(1, "%s: %s", format->filename,
strerror(errno));;
return ftello(format->fp);
}
/* format */
/* deasm_format_open */
static DeasmFormat const * _deasm_format_open(Deasm * deasm,
char const * format)
{
DeasmFormat * p;
#ifdef DEBUG
fprintf(stderr, "DEBUG: %s(\"%s\")\n", __func__, format);
#endif
if((p = realloc(deasm->format, sizeof(*p) * (deasm->format_cnt + 1)))
== NULL)
{
error_set_code(1, "%s", strerror(errno));
return NULL;
}
deasm->format = p;
p = &deasm->format[deasm->format_cnt];
if((p->plugin = plugin_new(LIBDIR, PACKAGE, "format", format)) == NULL)
return NULL;
if((p->format = plugin_lookup(p->plugin, "format_plugin")) == NULL)
{
plugin_delete(p->plugin);
return NULL;
}
if(p->format->decode == NULL)
{
error_set_code(1, "%s: %s", format,
"Does not support disassembly");
plugin_delete(p->plugin);
return NULL;
}
p->format->helper = &deasm->helper;
deasm->format_cnt++;
return p;
}
/* deasm_format_open_all */
static int _deasm_format_open_all(Deasm * deasm)
{
char const path[] = LIBDIR "/" PACKAGE "/format";
DIR * dir;
struct dirent * de;
size_t len;
char const ext[] = ".so";
if((dir = opendir(path)) == NULL)
return -error_set_print("deasm", 1, "%s: %s", path, strerror(
errno));
while((de = readdir(dir)) != NULL)
{
if((len = strlen(de->d_name)) < 4)
continue;
if(strcmp(&de->d_name[len - sizeof(ext) + 1], ext) != 0)
continue;
de->d_name[len - sizeof(ext) + 1] = '\0';
if(_deasm_format_open(deasm, de->d_name) == NULL)
error_print("deasm");
}
closedir(dir);
return 0;
}
#if 0
/* deasm_format_callback */
static int _callback_flat(Deasm * deasm, off_t offset, size_t size, off_t base);
static int _deasm_format_decode(Format * format, char const * section,
off_t offset, size_t size, off_t base)
{
Deasm * deasm = format;
if(section != NULL)
printf("\n%s%s\n", "Disassembly of section: ", section);
return _callback_flat(deasm, offset, size, base);
}
static int _callback_flat(Deasm * deasm, off_t offset, size_t size, off_t base)
{
#ifdef DEBUG
fprintf(stderr, "DEBUG: %s(0x%lx, 0x%lx, 0x%lx)\n", __func__, offset,
size, base);
#endif
if(fseek(deasm->fp, offset, SEEK_SET) != 0)
return -_deasm_error(deasm->filename, 1);
printf("\n%08lx:\n", offset + base);
return 0;
}
#endif
/* deasm_format_detect */
static char const * _deasm_format_detect(DeasmFormat const * format)
{
if(format->format->detect == NULL)
return NULL;
return format->format->detect(format->format);
}
/* deasm_format_close */
static void _deasm_format_close(DeasmFormat const * format)
{
#ifdef DEBUG
fprintf(stderr, "DEBUG: %s() \"%s\"\n", __func__, format->format->name);
#endif
plugin_delete(format->plugin);
}
/* deasm_format_close_all */
static void _deasm_format_close_all(Deasm * deasm)
{
size_t i;
for(i = 0; i < deasm->format_cnt; i++)
_deasm_format_close(&deasm->format[i]);
free(deasm->format);
deasm->format = NULL;
deasm->format_cnt = 0;
}
/* usage */
static int _usage(void)
{
fputs("Usage: deasm [-a arch][-f format] filename\n"
" deasm [-a arch][-f format] -s string\n"
" deasm -l\n", stderr);
return 1;
}
/* public */
/* functions */
/* main */
int main(int argc, char * argv[])
{
int o;
char const * arch = NULL;
char const * format = NULL;
char const * string = NULL;
while((o = getopt(argc, argv, "a:f:ls:")) != -1)
switch(o)
{
case 'a':
arch = optarg;
break;
case 'f':
format = optarg;
break;
case 'l':
return _deasm_list();
case 's':
string = optarg;
break;
default:
return _usage();
}
if(optind == argc && string != NULL)
return _deasm_string(arch, format, string);
else if(optind + 1 == argc && string == NULL)
return (_deasm(arch, format, argv[optind]) == 0) ? 0 : 2;
return _usage();
}

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@ -1,5 +1,5 @@
subdirs=arch,format
targets=libasm,asm
targets=libasm,asm,deasm
cppflags_force=-I ../include
cppflags=
cflags_force=-W `pkg-config --cflags cpp`
@ -21,6 +21,13 @@ depends=libasm.so
ldflags=-L. -Wl,-rpath,$(LIBDIR) -lasm
install=$(BINDIR)
[deasm]
type=binary
sources=deasm.c
depends=libasm.so
ldflags=-L. -Wl,-rpath,$(LIBDIR) -lasm
install=$(BINDIR)
[arch.c]
depends=arch.h,../config.h
@ -30,6 +37,9 @@ depends=../include/Asm.h,code.h,parser.h,asm.h,../config.h
[code.c]
depends=../include/Asm.h,arch.h,code.h
[deasm.c]
depends=../include/Asm.h
[format.c]
depends=format.h,../config.h