linux/arch/cris/arch-v10/boot/tools/build.c
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   1/*
   2 *  linux/tools/build.c
   3 *
   4 *  Copyright (C) 1991, 1992  Linus Torvalds
   5 */
   6
   7/*
   8 * This file builds a disk-image from three different files:
   9 *
  10 * - bootsect: exactly 512 bytes of 8086 machine code, loads the rest
  11 * - setup: 8086 machine code, sets up system parm
  12 * - system: 80386 code for actual system
  13 *
  14 * It does some checking that all files are of the correct type, and
  15 * just writes the result to stdout, removing headers and padding to
  16 * the right amount. It also writes some system data to stderr.
  17 */
  18
  19/*
  20 * Changes by tytso to allow root device specification
  21 * High loaded stuff by Hans Lermen & Werner Almesberger, Feb. 1996
  22 * Cross compiling fixes by Gertjan van Wingerde, July 1996
  23 */
  24
  25#include <stdio.h>      /* fprintf */
  26#include <string.h>
  27#include <stdlib.h>     /* contains exit */
  28#include <sys/types.h>  /* unistd.h needs this */
  29#include <sys/stat.h>
  30#include <sys/sysmacros.h>
  31#include <unistd.h>     /* contains read/write */
  32#include <fcntl.h>
  33#include <linux/a.out.h>
  34#include <errno.h>
  35
  36#define MINIX_HEADER 32
  37
  38#define N_MAGIC_OFFSET 1024
  39#ifndef __BFD__
  40static int GCC_HEADER = sizeof(struct exec);
  41#endif
  42
  43#ifdef __BIG_KERNEL__
  44#define SYS_SIZE 0xffff
  45#else
  46#define SYS_SIZE DEF_SYSSIZE
  47#endif
  48
  49#define DEFAULT_MAJOR_ROOT 0
  50#define DEFAULT_MINOR_ROOT 0
  51
  52/* max nr of sectors of setup: don't change unless you also change
  53 * bootsect etc */
  54#define SETUP_SECTS 4
  55
  56#define STRINGIFY(x) #x
  57
  58typedef union {
  59        int i;
  60        long l;
  61        short s[2];
  62        char b[4];
  63} conv;
  64
  65long intel_long(long l)
  66{
  67        conv t;
  68
  69        t.b[0] = l & 0xff; l >>= 8;
  70        t.b[1] = l & 0xff; l >>= 8;
  71        t.b[2] = l & 0xff; l >>= 8;
  72        t.b[3] = l & 0xff; l >>= 8;
  73        return t.l;
  74}
  75
  76int intel_int(int i)
  77{
  78        conv t;
  79
  80        t.b[0] = i & 0xff; i >>= 8;
  81        t.b[1] = i & 0xff; i >>= 8;
  82        t.b[2] = i & 0xff; i >>= 8;
  83        t.b[3] = i & 0xff; i >>= 8;
  84        return t.i;
  85}
  86
  87short intel_short(short l)
  88{
  89        conv t;
  90
  91        t.b[0] = l & 0xff; l >>= 8;
  92        t.b[1] = l & 0xff; l >>= 8;
  93        return t.s[0];
  94}
  95
  96void die(const char * str)
  97{
  98        fprintf(stderr,"%s\n",str);
  99        exit(1);
 100}
 101
 102void usage(void)
 103{
 104        die("Usage: build bootsect setup system [rootdev] [> image]");
 105}
 106
 107int main(int argc, char ** argv)
 108{
 109        int i,c,id,sz,tmp_int;
 110        unsigned long sys_size, tmp_long;
 111        char buf[1024];
 112#ifndef __BFD__
 113        struct exec *ex = (struct exec *)buf;
 114#endif
 115        char major_root, minor_root;
 116        struct stat sb;
 117        unsigned char setup_sectors;
 118
 119        if ((argc < 4) || (argc > 5))
 120                usage();
 121        if (argc > 4) {
 122                if (!strcmp(argv[4], "CURRENT")) {
 123                        if (stat("/", &sb)) {
 124                                perror("/");
 125                                die("Couldn't stat /");
 126                        }
 127                        major_root = major(sb.st_dev);
 128                        minor_root = minor(sb.st_dev);
 129                } else if (strcmp(argv[4], "FLOPPY")) {
 130                        if (stat(argv[4], &sb)) {
 131                                perror(argv[4]);
 132                                die("Couldn't stat root device.");
 133                        }
 134                        major_root = major(sb.st_rdev);
 135                        minor_root = minor(sb.st_rdev);
 136                } else {
 137                        major_root = 0;
 138                        minor_root = 0;
 139                }
 140        } else {
 141                major_root = DEFAULT_MAJOR_ROOT;
 142                minor_root = DEFAULT_MINOR_ROOT;
 143        }
 144        fprintf(stderr, "Root device is (%d, %d)\n", major_root, minor_root);
 145        for (i=0;i<sizeof buf; i++) buf[i]=0;
 146        if ((id=open(argv[1],O_RDONLY,0))<0)
 147                die("Unable to open 'boot'");
 148        if (read(id,buf,MINIX_HEADER) != MINIX_HEADER)
 149                die("Unable to read header of 'boot'");
 150        if (((long *) buf)[0]!=intel_long(0x04100301))
 151                die("Non-Minix header of 'boot'");
 152        if (((long *) buf)[1]!=intel_long(MINIX_HEADER))
 153                die("Non-Minix header of 'boot'");
 154        if (((long *) buf)[3] != 0)
 155                die("Illegal data segment in 'boot'");
 156        if (((long *) buf)[4] != 0)
 157                die("Illegal bss in 'boot'");
 158        if (((long *) buf)[5] != 0)
 159                die("Non-Minix header of 'boot'");
 160        if (((long *) buf)[7] != 0)
 161                die("Illegal symbol table in 'boot'");
 162        i=read(id,buf,sizeof buf);
 163        fprintf(stderr,"Boot sector %d bytes.\n",i);
 164        if (i != 512)
 165                die("Boot block must be exactly 512 bytes");
 166        if ((*(unsigned short *)(buf+510)) != (unsigned short)intel_short(0xAA55))
 167                die("Boot block hasn't got boot flag (0xAA55)");
 168        buf[508] = (char) minor_root;
 169        buf[509] = (char) major_root;   
 170        i=write(1,buf,512);
 171        if (i!=512)
 172                die("Write call failed");
 173        close (id);
 174        
 175        if ((id=open(argv[2],O_RDONLY,0))<0)
 176                die("Unable to open 'setup'");
 177        if (read(id,buf,MINIX_HEADER) != MINIX_HEADER)
 178                die("Unable to read header of 'setup'");
 179        if (((long *) buf)[0]!=intel_long(0x04100301))
 180                die("Non-Minix header of 'setup'");
 181        if (((long *) buf)[1]!=intel_long(MINIX_HEADER))
 182                die("Non-Minix header of 'setup'");
 183        if (((long *) buf)[3] != 0)
 184                die("Illegal data segment in 'setup'");
 185        if (((long *) buf)[4] != 0)
 186                die("Illegal bss in 'setup'");
 187        if (((long *) buf)[5] != 0)
 188                die("Non-Minix header of 'setup'");
 189        if (((long *) buf)[7] != 0)
 190                die("Illegal symbol table in 'setup'");
 191        for (i=0 ; (c=read(id,buf,sizeof buf))>0 ; i+=c )
 192#ifdef __BIG_KERNEL__
 193        {
 194                if (!i) {
 195                        /* Working with memcpy because of alignment constraints
 196                           on Sparc - Gertjan */
 197                        memcpy(&tmp_long, &buf[2], sizeof(long));
 198                        if (tmp_long != intel_long(0x53726448) )
 199                                die("Wrong magic in loader header of 'setup'");
 200                        memcpy(&tmp_int, &buf[6], sizeof(int));
 201                        if (tmp_int < intel_int(0x200))
 202                                die("Wrong version of loader header of 'setup'");
 203                        buf[0x11] = 1; /* LOADED_HIGH */
 204                        tmp_long = intel_long(0x100000);
 205                        memcpy(&buf[0x14], &tmp_long, sizeof(long));  /* code32_start */
 206                }
 207#endif
 208                if (write(1,buf,c)!=c)
 209                        die("Write call failed");
 210#ifdef __BIG_KERNEL__
 211        }
 212#endif
 213        if (c != 0)
 214                die("read-error on 'setup'");
 215        close (id);
 216        setup_sectors = (unsigned char)((i + 511) / 512);
 217        /* for compatibility with LILO */
 218        if (setup_sectors < SETUP_SECTS)
 219                setup_sectors = SETUP_SECTS;
 220        fprintf(stderr,"Setup is %d bytes.\n",i);
 221        for (c=0 ; c<sizeof(buf) ; c++)
 222                buf[c] = '\0';
 223        while (i < setup_sectors * 512) {
 224                c = setup_sectors * 512 - i;
 225                if (c > sizeof(buf))
 226                        c = sizeof(buf);
 227                if (write(1,buf,c) != c)
 228                        die("Write call failed");
 229                i += c;
 230        }
 231        
 232        if ((id=open(argv[3],O_RDONLY,0))<0)
 233                die("Unable to open 'system'");
 234#ifndef __BFD__
 235        if (read(id,buf,GCC_HEADER) != GCC_HEADER)
 236                die("Unable to read header of 'system'");
 237        if (N_MAGIC(*ex) == ZMAGIC) {
 238                GCC_HEADER = N_MAGIC_OFFSET;
 239                lseek(id, GCC_HEADER, SEEK_SET);
 240        } else if (N_MAGIC(*ex) != QMAGIC)
 241                die("Non-GCC header of 'system'");
 242        fprintf(stderr,"System is %d kB (%d kB code, %d kB data and %d kB bss)\n",
 243                (ex->a_text+ex->a_data+ex->a_bss)/1024,
 244                ex->a_text /1024,
 245                ex->a_data /1024,
 246                ex->a_bss  /1024);
 247        sz = N_SYMOFF(*ex) - GCC_HEADER + 4;
 248#else
 249        if (fstat (id, &sb)) {
 250          perror ("fstat");
 251          die ("Unable to stat 'system'");
 252        }
 253        sz = sb.st_size;
 254        fprintf (stderr, "System is %d kB\n", sz/1024);
 255#endif
 256        sys_size = (sz + 15) / 16;
 257        if (sys_size > SYS_SIZE)
 258                die("System is too big");
 259        while (sz > 0) {
 260                int l, n;
 261
 262                l = sz;
 263                if (l > sizeof(buf))
 264                        l = sizeof(buf);
 265                if ((n=read(id, buf, l)) != l) {
 266                        if (n == -1) 
 267                                perror(argv[1]);
 268                        else
 269                                fprintf(stderr, "Unexpected EOF\n");
 270                        die("Can't read 'system'");
 271                }
 272                if (write(1, buf, l) != l)
 273                        die("Write failed");
 274                sz -= l;
 275        }
 276        close(id);
 277        if (lseek(1, 497, 0) == 497) {
 278                if (write(1, &setup_sectors, 1) != 1)
 279                        die("Write of setup sectors failed");
 280        }
 281        if (lseek(1,500,0) == 500) {
 282                buf[0] = (sys_size & 0xff);
 283                buf[1] = ((sys_size >> 8) & 0xff);
 284                if (write(1, buf, 2) != 2)
 285                        die("Write failed");
 286        }
 287        return(0);
 288}
 289
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