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