src/file/file.c

/*
 *  Copyright (C) 2003-2007  Anders Gavare.  All rights reserved.
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions are met:
 *
 *  1. Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *  2. Redistributions in binary form must reproduce the above copyright  
 *     notice, this list of conditions and the following disclaimer in the 
 *     documentation and/or other materials provided with the distribution.
 *  3. The name of the author may not be used to endorse or promote products
 *     derived from this software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 *  ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 *  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 *  ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE   
 *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 *  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 *  OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 *  HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 *  LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 *  OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 *  SUCH DAMAGE.
 *
 *
 *  $Id: file.c,v 1.1 2007/04/10 16:33:44 debug Exp $
 *
 *  This module contains functions which load executable images into (emulated)
 *  memory. File formats recognized so far are:
 *
 *      a.out           old format used by OpenBSD 2.x pmax kernels
 *      Mach-O          MacOS X format, etc.
 *      ecoff           old format used by Ultrix, Windows NT, etc
 *      srec            Motorola SREC format
 *      raw             raw binaries, "address:[skiplen:[entrypoint:]]filename"
 *      ELF             32-bit and 64-bit ELFs
 *
 *  If a file is not of one of the above mentioned formats, it is assumed
 *  to be symbol data generated by 'nm' or 'nm -S'.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>

#include "cpu.h"
#include "machine.h"
#include "memory.h"
#include "misc.h"
#include "symbol.h"


extern int quiet_mode;
extern int verbose;


/*
 *  This should be increased by every routine here that actually loads an
 *  executable file into memory.  (For example, loading a symbol file should
 *  NOT increase this.)
 */
static int n_executables_loaded = 0;


#include "exec_elf.h"           /*  Ugly; needed for ELFDATA2LSB etc.  */

#define unencode(var,dataptr,typ)       {                               \
                int Wi;  unsigned char Wb;                              \
                unsigned char *Wp = (unsigned char *) dataptr;          \
                int Wlen = sizeof(typ);                                 \
                var = 0;                                                \
                for (Wi=0; Wi<Wlen; Wi++) {                             \
                        if (encoding == ELFDATA2LSB)                    \
                                Wb = Wp[Wlen-1 - Wi];                   \
                        else                                            \
                                Wb = Wp[Wi];                            \
                        if (Wi == 0 && (Wb & 0x80)) {                   \
                                var --; /*  set var to -1 :-)  */       \
                                var <<= 8;                              \
                        }                                               \
                        var |= Wb;                                      \
                        if (Wi < Wlen-1)                                \
                                var <<= 8;                              \
                }                                                       \
        }


#include "file_aout.c"
#include "file_ecoff.c"
#include "file_elf.c"
#include "file_macho.c"
#include "file_raw.c"
#include "file_srec.c"


/*
 *  file_n_executables_loaded():
 *
 *  Returns the number of executable files loaded into emulated memory.
 */
int file_n_executables_loaded(void)
{
        return n_executables_loaded;
}


/*
 *  file_load():
 *
 *  Sense the file format of a file (ELF, a.out, ecoff), and call the
 *  right file_load_XXX() function.  If the file isn't of a recognized
 *  binary format, assume that it contains symbol definitions.
 *
 *  If the filename doesn't exist, try to treat the name as
 *   "address:filename" and load the file as a raw binary.
 */
void file_load(struct machine *machine, struct memory *mem,
        char *filename, uint64_t *entrypointp,
        int arch, uint64_t *gpp, int *byte_orderp, uint64_t *tocp)
{
        int iadd = DEBUG_INDENTATION, old_quiet_mode;
        FILE *f;
        unsigned char buf[12];
        unsigned char buf2[2];
        size_t len, len2, i;
        off_t size;

        if (byte_orderp == NULL) {
                fprintf(stderr, "file_load(): byte_order == NULL\n");
                exit(1);
        }

        if (arch == ARCH_NOARCH) {
                fprintf(stderr, "file_load(): FATAL ERROR: no arch?\n");
                exit(1);
        }

        if (mem == NULL || filename == NULL) {
                fprintf(stderr, "file_load(): mem or filename is NULL\n");
                exit(1);
        }

        /*  Skip configuration files:  */
        if (filename[0] == '@')
                return;

        debug("loading %s%s\n", filename, verbose >= 2? ":" : "");
        debug_indentation(iadd);

        old_quiet_mode = quiet_mode;
        if (verbose < 2)
                quiet_mode = 1;

        f = fopen(filename, "r");
        if (f == NULL) {
                file_load_raw(machine, mem, filename, entrypointp);
                goto ret;
        }

        fseek(f, 0, SEEK_END);
        size = ftello(f);
        fseek(f, 0, SEEK_SET);

        memset(buf, 0, sizeof(buf));
        len = fread(buf, 1, sizeof(buf), f);
        fseek(f, 510, SEEK_SET);
        len2 = fread(buf2, 1, sizeof(buf2), f);
        fclose(f);

        if (len < (signed int)sizeof(buf)) {
                fprintf(stderr, "\nThis file is too small to contain "
                    "anything useful\n");
                exit(1);
        }

        /*  Is it an ELF?  */
        if (buf[0] == 0x7f && buf[1]=='E' && buf[2]=='L' && buf[3]=='F') {
                file_load_elf(machine, mem, filename,
                    entrypointp, arch, gpp, byte_orderp, tocp);
                goto ret;
        }

        /*  Is it an a.out?  */
        if (buf[0]==0x00 && buf[1]==0x8b && buf[2]==0x01 && buf[3]==0x07) {
                /*  MIPS a.out  */
                file_load_aout(machine, mem, filename, 0,
                    entrypointp, arch, byte_orderp);
                goto ret;
        }
        if (buf[0]==0x00 && buf[1]==0x87 && buf[2]==0x01 && buf[3]==0x08) {
                /*  M68K a.out  */
                file_load_aout(machine, mem, filename,
                    AOUT_FLAG_VADDR_ZERO_HACK  /*  for OpenBSD/mac68k  */,
                    entrypointp, arch, byte_orderp);
                goto ret;
        }
        if (buf[0]==0x00 && buf[1]==0x8f && buf[2]==0x01 && buf[3]==0x0b) {
                /*  ARM a.out  */
                file_load_aout(machine, mem, filename, AOUT_FLAG_FROM_BEGINNING,
                    entrypointp, arch, byte_orderp);
                goto ret;
        }
        if (buf[0]==0x00 && buf[1]==0x86 && buf[2]==0x01 && buf[3]==0x0b) {
                /*  i386 a.out (old OpenBSD and NetBSD etc)  */
                file_load_aout(machine, mem, filename, AOUT_FLAG_FROM_BEGINNING,
                    entrypointp, arch, byte_orderp);
                goto ret;
        }
        if (buf[0]==0x01 && buf[1]==0x03 && buf[2]==0x01 && buf[3]==0x07) {
                /*  SPARC a.out (old 32-bit NetBSD etc)  */
                file_load_aout(machine, mem, filename, AOUT_FLAG_NO_SIZES,
                    entrypointp, arch, byte_orderp);
                goto ret;
        }
        if (buf[0]==0x00 && buf[2]==0x00 && buf[8]==0x7a && buf[9]==0x75) {
                /*  DEC OSF1 on MIPS:  */
                file_load_aout(machine, mem, filename, AOUT_FLAG_DECOSF1,
                    entrypointp, arch, byte_orderp);
                goto ret;
        }

        /*
         *  Is it a Mach-O file?
         */
        if (buf[0] == 0xfe && buf[1] == 0xed && buf[2] == 0xfa &&
            (buf[3] == 0xce || buf[3] == 0xcf)) {
                file_load_macho(machine, mem, filename, entrypointp,
                    arch, byte_orderp, buf[3] == 0xcf, 0);
                goto ret;
        }
        if ((buf[0] == 0xce || buf[0] == 0xcf) && buf[1] == 0xfa &&
            buf[2] == 0xed && buf[3] == 0xfe) {
                file_load_macho(machine, mem, filename, entrypointp,
                    arch, byte_orderp, buf[0] == 0xcf, 1);
                goto ret;
        }

        /*
         *  Is it an ecoff?
         *
         *  TODO: What's the deal with the magic value's byte order? Sometimes
         *  it seems to be reversed for BE when compared to LE, but not always?
         */
        if (buf[0]+256*buf[1] == ECOFF_MAGIC_MIPSEB ||
            buf[0]+256*buf[1] == ECOFF_MAGIC_MIPSEL ||
            buf[0]+256*buf[1] == ECOFF_MAGIC_MIPSEB2 ||
            buf[0]+256*buf[1] == ECOFF_MAGIC_MIPSEL2 ||
            buf[0]+256*buf[1] == ECOFF_MAGIC_MIPSEB3 ||
            buf[0]+256*buf[1] == ECOFF_MAGIC_MIPSEL3 ||
            buf[1]+256*buf[0] == ECOFF_MAGIC_MIPSEB ||
            buf[1]+256*buf[0] == ECOFF_MAGIC_MIPSEL ||
            buf[1]+256*buf[0] == ECOFF_MAGIC_MIPSEB2 ||
            buf[1]+256*buf[0] == ECOFF_MAGIC_MIPSEL2 ||
            buf[1]+256*buf[0] == ECOFF_MAGIC_MIPSEB3 ||
            buf[1]+256*buf[0] == ECOFF_MAGIC_MIPSEL3) {
                file_load_ecoff(machine, mem, filename, entrypointp,
                    arch, gpp, byte_orderp);
                goto ret;
        }

        /*  Is it a Motorola SREC file?  */
        if ((buf[0]=='S' && buf[1]>='0' && buf[1]<='9')) {
                file_load_srec(machine, mem, filename, entrypointp);
                goto ret;
        }

        /*  gzipped files are not supported:  */
        if (buf[0]==0x1f && buf[1]==0x8b) {
                fprintf(stderr, "\nYou need to gunzip the file before you"
                    " try to use it.\n");
                exit(1);
        }

        if (size > 24000000) {
                fprintf(stderr, "\nThis file is very large (%lli bytes)\n",
                    (long long)size);
                fprintf(stderr, "Are you sure it is a kernel and not a disk "
                    "image? (Use the -d option.)\n");
                exit(1);
        }

        if (size == 1474560)
                fprintf(stderr, "Hm... this file is the size of a 1.44 MB "
                    "floppy image. Maybe you forgot the\n-d switch?\n");

        /*
         *  Ugly hack for Dreamcast:  When booting from a Dreamcast CDROM
         *  image, a temporary file is extracted into /tmp/gxemul.*, but this
         *  is a "scrambled" raw binary. This code unscrambles it, and loads
         *  it as a raw binary.
         */
        if (machine->machine_type == MACHINE_DREAMCAST &&
            strncmp(filename, "/tmp/gxemul.", 12) == 0) {
                char *tmp_filename = malloc(strlen(filename) + 100);
                snprintf(tmp_filename, strlen(filename) + 100,
                    "%s.descrambled", filename);
                debug("descrambling into %s\n", tmp_filename);
                dreamcast_descramble(filename, tmp_filename);

                snprintf(tmp_filename, strlen(filename) + 100,
                    "0x8c010000:%s.descrambled", filename);
                debug("loading descrambled Dreamcast binary\n");
                file_load_raw(machine, mem, tmp_filename, entrypointp);
                free(tmp_filename);

                /*  Hack: Start a "boot from CDROM" sequence:  */
                *entrypointp = 0x8c000080;
                goto ret;
        }

        /*
         *  Last resort:  symbol definitions from nm (or nm -S):
         *
         *  If the buf contains typical 'binary' characters, then print
         *  an error message and quit instead of assuming that it is a
         *  symbol file.
         */
        for (i=0; i<(signed)sizeof(buf); i++)
                if (buf[i] < 32 && buf[i] != '\t' &&
                    buf[i] != '\n' && buf[i] != '\r' &&
                    buf[i] != '\f') {
                        fprintf(stderr, "\nThe file format of '%s' is "
                            "unknown.\n\n ", filename);
                        for (i=0; i<(signed)sizeof(buf); i++)
                                fprintf(stderr, " %02x", buf[i]);

                        if (len2 == 2 && buf2[0] == 0x55 && buf2[1] == 0xaa)
                                fprintf(stderr, "\n\nIt has a PC-style "
                                    "bootsector marker.");

                        fprintf(stderr, "\n\nPossible explanations:\n\n"
                            "  o)  If this is a disk image, you forgot '-d' "
                            "on the command line.\n"
                            "  o)  This is an unsupported binary format.\n\n");
                        exit(1);
                }

        symbol_readfile(&machine->symbol_context, filename);

ret:
        debug_indentation(-iadd);
        quiet_mode = old_quiet_mode;
}

1	dpavlin	38	/*
2			* Copyright (C) 2003-2007 Anders Gavare. All rights reserved.
3			*
4			* Redistribution and use in source and binary forms, with or without
5			* modification, are permitted provided that the following conditions are met:
6			*
7			* 1. Redistributions of source code must retain the above copyright
8			* notice, this list of conditions and the following disclaimer.
9			* 2. Redistributions in binary form must reproduce the above copyright
10			* notice, this list of conditions and the following disclaimer in the
11			* documentation and/or other materials provided with the distribution.
12			* 3. The name of the author may not be used to endorse or promote products
13			* derived from this software without specific prior written permission.
14			*
15			* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16			* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17			* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18			* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19			* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20			* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21			* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22			* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23			* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24			* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25			* SUCH DAMAGE.
26			*
27			*
28			* $Id: file.c,v 1.1 2007/04/10 16:33:44 debug Exp $
29			*
30			* This module contains functions which load executable images into (emulated)
31			* memory. File formats recognized so far are:
32			*
33			* a.out old format used by OpenBSD 2.x pmax kernels
34			* Mach-O MacOS X format, etc.
35			* ecoff old format used by Ultrix, Windows NT, etc
36			* srec Motorola SREC format
37			* raw raw binaries, "address:[skiplen:[entrypoint:]]filename"
38			* ELF 32-bit and 64-bit ELFs
39			*
40			* If a file is not of one of the above mentioned formats, it is assumed
41			* to be symbol data generated by 'nm' or 'nm -S'.
42			*/
43
44			#include <stdio.h>
45			#include <stdlib.h>
46			#include <string.h>
47			#include <sys/types.h>
48
49			#include "cpu.h"
50			#include "machine.h"
51			#include "memory.h"
52			#include "misc.h"
53			#include "symbol.h"
54
55
56			extern int quiet_mode;
57			extern int verbose;
58
59
60			/*
61			* This should be increased by every routine here that actually loads an
62			* executable file into memory. (For example, loading a symbol file should
63			* NOT increase this.)
64			*/
65			static int n_executables_loaded = 0;
66
67
68			#include "exec_elf.h" /* Ugly; needed for ELFDATA2LSB etc. */
69
70			#define unencode(var,dataptr,typ) { \
71			int Wi; unsigned char Wb; \
72			unsigned char Wp = (unsigned char ) dataptr; \
73			int Wlen = sizeof(typ); \
74			var = 0; \
75			for (Wi=0; Wi<Wlen; Wi++) { \
76			if (encoding == ELFDATA2LSB) \
77			Wb = Wp[Wlen-1 - Wi]; \
78			else \
79			Wb = Wp[Wi]; \
80			if (Wi == 0 && (Wb & 0x80)) { \
81			var --; /* set var to -1 :-) */ \
82			var <<= 8; \
83			} \
84			var \|= Wb; \
85			if (Wi < Wlen-1) \
86			var <<= 8; \
87			} \
88			}
89
90
91			#include "file_aout.c"
92			#include "file_ecoff.c"
93			#include "file_elf.c"
94			#include "file_macho.c"
95			#include "file_raw.c"
96			#include "file_srec.c"
97
98
99			/*
100			* file_n_executables_loaded():
101			*
102			* Returns the number of executable files loaded into emulated memory.
103			*/
104			int file_n_executables_loaded(void)
105			{
106			return n_executables_loaded;
107			}
108
109
110			/*
111			* file_load():
112			*
113			* Sense the file format of a file (ELF, a.out, ecoff), and call the
114			* right file_load_XXX() function. If the file isn't of a recognized
115			* binary format, assume that it contains symbol definitions.
116			*
117			* If the filename doesn't exist, try to treat the name as
118			* "address:filename" and load the file as a raw binary.
119			*/
120			void file_load(struct machine machine, struct memory mem,
121			char filename, uint64_t entrypointp,
122			int arch, uint64_t gpp, int byte_orderp, uint64_t *tocp)
123			{
124			int iadd = DEBUG_INDENTATION, old_quiet_mode;
125			FILE *f;
126			unsigned char buf[12];
127			unsigned char buf2[2];
128			size_t len, len2, i;
129			off_t size;
130
131			if (byte_orderp == NULL) {
132			fprintf(stderr, "file_load(): byte_order == NULL\n");
133			exit(1);
134			}
135
136			if (arch == ARCH_NOARCH) {
137			fprintf(stderr, "file_load(): FATAL ERROR: no arch?\n");
138			exit(1);
139			}
140
141			if (mem == NULL \|\| filename == NULL) {
142			fprintf(stderr, "file_load(): mem or filename is NULL\n");
143			exit(1);
144			}
145
146			/* Skip configuration files: */
147			if (filename[0] == '@')
148			return;
149
150			debug("loading %s%s\n", filename, verbose >= 2? ":" : "");
151			debug_indentation(iadd);
152
153			old_quiet_mode = quiet_mode;
154			if (verbose < 2)
155			quiet_mode = 1;
156
157			f = fopen(filename, "r");
158			if (f == NULL) {
159			file_load_raw(machine, mem, filename, entrypointp);
160			goto ret;
161			}
162
163			fseek(f, 0, SEEK_END);
164			size = ftello(f);
165			fseek(f, 0, SEEK_SET);
166
167			memset(buf, 0, sizeof(buf));
168			len = fread(buf, 1, sizeof(buf), f);
169			fseek(f, 510, SEEK_SET);
170			len2 = fread(buf2, 1, sizeof(buf2), f);
171			fclose(f);
172
173			if (len < (signed int)sizeof(buf)) {
174			fprintf(stderr, "\nThis file is too small to contain "
175			"anything useful\n");
176			exit(1);
177			}
178
179			/* Is it an ELF? */
180			if (buf[0] == 0x7f && buf[1]=='E' && buf[2]=='L' && buf[3]=='F') {
181			file_load_elf(machine, mem, filename,
182			entrypointp, arch, gpp, byte_orderp, tocp);
183			goto ret;
184			}
185
186			/* Is it an a.out? */
187			if (buf[0]==0x00 && buf[1]==0x8b && buf[2]==0x01 && buf[3]==0x07) {
188			/* MIPS a.out */
189			file_load_aout(machine, mem, filename, 0,
190			entrypointp, arch, byte_orderp);
191			goto ret;
192			}
193			if (buf[0]==0x00 && buf[1]==0x87 && buf[2]==0x01 && buf[3]==0x08) {
194			/* M68K a.out */
195			file_load_aout(machine, mem, filename,
196			AOUT_FLAG_VADDR_ZERO_HACK /* for OpenBSD/mac68k */,
197			entrypointp, arch, byte_orderp);
198			goto ret;
199			}
200			if (buf[0]==0x00 && buf[1]==0x8f && buf[2]==0x01 && buf[3]==0x0b) {
201			/* ARM a.out */
202			file_load_aout(machine, mem, filename, AOUT_FLAG_FROM_BEGINNING,
203			entrypointp, arch, byte_orderp);
204			goto ret;
205			}
206			if (buf[0]==0x00 && buf[1]==0x86 && buf[2]==0x01 && buf[3]==0x0b) {
207			/* i386 a.out (old OpenBSD and NetBSD etc) */
208			file_load_aout(machine, mem, filename, AOUT_FLAG_FROM_BEGINNING,
209			entrypointp, arch, byte_orderp);
210			goto ret;
211			}
212			if (buf[0]==0x01 && buf[1]==0x03 && buf[2]==0x01 && buf[3]==0x07) {
213			/* SPARC a.out (old 32-bit NetBSD etc) */
214			file_load_aout(machine, mem, filename, AOUT_FLAG_NO_SIZES,
215			entrypointp, arch, byte_orderp);
216			goto ret;
217			}
218			if (buf[0]==0x00 && buf[2]==0x00 && buf[8]==0x7a && buf[9]==0x75) {
219			/* DEC OSF1 on MIPS: */
220			file_load_aout(machine, mem, filename, AOUT_FLAG_DECOSF1,
221			entrypointp, arch, byte_orderp);
222			goto ret;
223			}
224
225			/*
226			* Is it a Mach-O file?
227			*/
228			if (buf[0] == 0xfe && buf[1] == 0xed && buf[2] == 0xfa &&
229			(buf[3] == 0xce \|\| buf[3] == 0xcf)) {
230			file_load_macho(machine, mem, filename, entrypointp,
231			arch, byte_orderp, buf[3] == 0xcf, 0);
232			goto ret;
233			}
234			if ((buf[0] == 0xce \|\| buf[0] == 0xcf) && buf[1] == 0xfa &&
235			buf[2] == 0xed && buf[3] == 0xfe) {
236			file_load_macho(machine, mem, filename, entrypointp,
237			arch, byte_orderp, buf[0] == 0xcf, 1);
238			goto ret;
239			}
240
241			/*
242			* Is it an ecoff?
243			*
244			* TODO: What's the deal with the magic value's byte order? Sometimes
245			* it seems to be reversed for BE when compared to LE, but not always?
246			*/
247			if (buf[0]+256*buf[1] == ECOFF_MAGIC_MIPSEB \|\|
248			buf[0]+256*buf[1] == ECOFF_MAGIC_MIPSEL \|\|
249			buf[0]+256*buf[1] == ECOFF_MAGIC_MIPSEB2 \|\|
250			buf[0]+256*buf[1] == ECOFF_MAGIC_MIPSEL2 \|\|
251			buf[0]+256*buf[1] == ECOFF_MAGIC_MIPSEB3 \|\|
252			buf[0]+256*buf[1] == ECOFF_MAGIC_MIPSEL3 \|\|
253			buf[1]+256*buf[0] == ECOFF_MAGIC_MIPSEB \|\|
254			buf[1]+256*buf[0] == ECOFF_MAGIC_MIPSEL \|\|
255			buf[1]+256*buf[0] == ECOFF_MAGIC_MIPSEB2 \|\|
256			buf[1]+256*buf[0] == ECOFF_MAGIC_MIPSEL2 \|\|
257			buf[1]+256*buf[0] == ECOFF_MAGIC_MIPSEB3 \|\|
258			buf[1]+256*buf[0] == ECOFF_MAGIC_MIPSEL3) {
259			file_load_ecoff(machine, mem, filename, entrypointp,
260			arch, gpp, byte_orderp);
261			goto ret;
262			}
263
264			/* Is it a Motorola SREC file? */
265			if ((buf[0]=='S' && buf[1]>='0' && buf[1]<='9')) {
266			file_load_srec(machine, mem, filename, entrypointp);
267			goto ret;
268			}
269
270			/* gzipped files are not supported: */
271			if (buf[0]==0x1f && buf[1]==0x8b) {
272			fprintf(stderr, "\nYou need to gunzip the file before you"
273			" try to use it.\n");
274			exit(1);
275			}
276
277			if (size > 24000000) {
278			fprintf(stderr, "\nThis file is very large (%lli bytes)\n",
279			(long long)size);
280			fprintf(stderr, "Are you sure it is a kernel and not a disk "
281			"image? (Use the -d option.)\n");
282			exit(1);
283			}
284
285			if (size == 1474560)
286			fprintf(stderr, "Hm... this file is the size of a 1.44 MB "
287			"floppy image. Maybe you forgot the\n-d switch?\n");
288
289			/*
290			* Ugly hack for Dreamcast: When booting from a Dreamcast CDROM
291			* image, a temporary file is extracted into /tmp/gxemul.*, but this
292			* is a "scrambled" raw binary. This code unscrambles it, and loads
293			* it as a raw binary.
294			*/
295			if (machine->machine_type == MACHINE_DREAMCAST &&
296			strncmp(filename, "/tmp/gxemul.", 12) == 0) {
297			char *tmp_filename = malloc(strlen(filename) + 100);
298			snprintf(tmp_filename, strlen(filename) + 100,
299			"%s.descrambled", filename);
300			debug("descrambling into %s\n", tmp_filename);
301			dreamcast_descramble(filename, tmp_filename);
302
303			snprintf(tmp_filename, strlen(filename) + 100,
304			"0x8c010000:%s.descrambled", filename);
305			debug("loading descrambled Dreamcast binary\n");
306			file_load_raw(machine, mem, tmp_filename, entrypointp);
307			free(tmp_filename);
308
309			/* Hack: Start a "boot from CDROM" sequence: */
310			*entrypointp = 0x8c000080;
311			goto ret;
312			}
313
314			/*
315			* Last resort: symbol definitions from nm (or nm -S):
316			*
317			* If the buf contains typical 'binary' characters, then print
318			* an error message and quit instead of assuming that it is a
319			* symbol file.
320			*/
321			for (i=0; i<(signed)sizeof(buf); i++)
322			if (buf[i] < 32 && buf[i] != '\t' &&
323			buf[i] != '\n' && buf[i] != '\r' &&
324			buf[i] != '\f') {
325			fprintf(stderr, "\nThe file format of '%s' is "
326			"unknown.\n\n ", filename);
327			for (i=0; i<(signed)sizeof(buf); i++)
328			fprintf(stderr, " %02x", buf[i]);
329
330			if (len2 == 2 && buf2[0] == 0x55 && buf2[1] == 0xaa)
331			fprintf(stderr, "\n\nIt has a PC-style "
332			"bootsector marker.");
333
334			fprintf(stderr, "\n\nPossible explanations:\n\n"
335			" o) If this is a disk image, you forgot '-d' "
336			"on the command line.\n"
337			" o) This is an unsupported binary format.\n\n");
338			exit(1);
339			}
340
341			symbol_readfile(&machine->symbol_context, filename);
342
343			ret:
344			debug_indentation(-iadd);
345			quiet_mode = old_quiet_mode;
346			}
347