This source file includes following definitions.
- intel_long
- intel_short
- die
- usage
- main
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23 #include <stdio.h>
24 #include <string.h>
25 #include <stdlib.h>
26 #include <sys/types.h>
27 #include <sys/stat.h>
28 #include <sys/sysmacros.h>
29 #include <unistd.h>
30 #include <fcntl.h>
31 #include <linux/config.h>
32 #include <linux/a.out.h>
33
34 #define MINIX_HEADER 32
35 #define GCC_HEADER 1024
36
37 #define SYS_SIZE DEF_SYSSIZE
38
39 #define DEFAULT_MAJOR_ROOT 0
40 #define DEFAULT_MINOR_ROOT 0
41
42
43
44 #define SETUP_SECTS 4
45
46 #define STRINGIFY(x) #x
47
48 typedef union {
49 long l;
50 short s[2];
51 char b[4];
52 } conv;
53
54 long intel_long(long l)
55 {
56 conv t;
57
58 t.b[0] = l & 0xff; l >>= 8;
59 t.b[1] = l & 0xff; l >>= 8;
60 t.b[2] = l & 0xff; l >>= 8;
61 t.b[3] = l & 0xff; l >>= 8;
62 return t.l;
63 }
64
65 short intel_short(short l)
66 {
67 conv t;
68
69 t.b[0] = l & 0xff; l >>= 8;
70 t.b[1] = l & 0xff; l >>= 8;
71 return t.s[0];
72 }
73
74 void die(char * str)
75 {
76 fprintf(stderr,"%s\n",str);
77 exit(1);
78 }
79
80 void usage(void)
81 {
82 die("Usage: build bootsect setup system [rootdev] [> image]");
83 }
84
85 int main(int argc, char ** argv)
86 {
87 int i,c,id, sz;
88 char buf[1024];
89 struct exec *ex = (struct exec *)buf;
90 char major_root, minor_root;
91 struct stat sb;
92
93 if ((argc < 4) || (argc > 5))
94 usage();
95 if (argc > 4) {
96 if (strcmp(argv[4], "FLOPPY")) {
97 if (stat(argv[4], &sb)) {
98 perror(argv[4]);
99 die("Couldn't stat root device.");
100 }
101 major_root = major(sb.st_rdev);
102 minor_root = minor(sb.st_rdev);
103 } else {
104 major_root = 0;
105 minor_root = 0;
106 }
107 } else {
108 major_root = DEFAULT_MAJOR_ROOT;
109 minor_root = DEFAULT_MINOR_ROOT;
110 }
111 fprintf(stderr, "Root device is (%d, %d)\n", major_root, minor_root);
112 for (i=0;i<sizeof buf; i++) buf[i]=0;
113 if ((id=open(argv[1],O_RDONLY,0))<0)
114 die("Unable to open 'boot'");
115 if (read(id,buf,MINIX_HEADER) != MINIX_HEADER)
116 die("Unable to read header of 'boot'");
117 if (((long *) buf)[0]!=intel_long(0x04100301))
118 die("Non-Minix header of 'boot'");
119 if (((long *) buf)[1]!=intel_long(MINIX_HEADER))
120 die("Non-Minix header of 'boot'");
121 if (((long *) buf)[3] != 0)
122 die("Illegal data segment in 'boot'");
123 if (((long *) buf)[4] != 0)
124 die("Illegal bss in 'boot'");
125 if (((long *) buf)[5] != 0)
126 die("Non-Minix header of 'boot'");
127 if (((long *) buf)[7] != 0)
128 die("Illegal symbol table in 'boot'");
129 i=read(id,buf,sizeof buf);
130 fprintf(stderr,"Boot sector %d bytes.\n",i);
131 if (i != 512)
132 die("Boot block must be exactly 512 bytes");
133 if ((*(unsigned short *)(buf+510)) != (unsigned short)intel_short(0xAA55))
134 die("Boot block hasn't got boot flag (0xAA55)");
135 buf[508] = (char) minor_root;
136 buf[509] = (char) major_root;
137 i=write(1,buf,512);
138 if (i!=512)
139 die("Write call failed");
140 close (id);
141
142 if ((id=open(argv[2],O_RDONLY,0))<0)
143 die("Unable to open 'setup'");
144 if (read(id,buf,MINIX_HEADER) != MINIX_HEADER)
145 die("Unable to read header of 'setup'");
146 if (((long *) buf)[0]!=intel_long(0x04100301))
147 die("Non-Minix header of 'setup'");
148 if (((long *) buf)[1]!=intel_long(MINIX_HEADER))
149 die("Non-Minix header of 'setup'");
150 if (((long *) buf)[3] != 0)
151 die("Illegal data segment in 'setup'");
152 if (((long *) buf)[4] != 0)
153 die("Illegal bss in 'setup'");
154 if (((long *) buf)[5] != 0)
155 die("Non-Minix header of 'setup'");
156 if (((long *) buf)[7] != 0)
157 die("Illegal symbol table in 'setup'");
158 for (i=0 ; (c=read(id,buf,sizeof buf))>0 ; i+=c )
159 if (write(1,buf,c)!=c)
160 die("Write call failed");
161 if (c != 0)
162 die("read-error on 'setup'");
163 close (id);
164 if (i > SETUP_SECTS*512)
165 die("Setup exceeds " STRINGIFY(SETUP_SECTS)
166 " sectors - rewrite build/boot/setup");
167 fprintf(stderr,"Setup is %d bytes.\n",i);
168 for (c=0 ; c<sizeof(buf) ; c++)
169 buf[c] = '\0';
170 while (i<SETUP_SECTS*512) {
171 c = SETUP_SECTS*512-i;
172 if (c > sizeof(buf))
173 c = sizeof(buf);
174 if (write(1,buf,c) != c)
175 die("Write call failed");
176 i += c;
177 }
178
179 if ((id=open(argv[3],O_RDONLY,0))<0)
180 die("Unable to open 'system'");
181 if (read(id,buf,GCC_HEADER) != GCC_HEADER)
182 die("Unable to read header of 'system'");
183 if (N_MAGIC(*ex) != ZMAGIC)
184 die("Non-GCC header of 'system'");
185 sz = N_SYMOFF(*ex) - GCC_HEADER + 4;
186 fprintf(stderr,"System is %d bytes.\n", sz);
187 if (sz > SYS_SIZE*16)
188 die("System is too big");
189 while (sz > 0) {
190 int l, n;
191
192 l = sz;
193 if (l > sizeof(buf))
194 l = sizeof(buf);
195 if ((n=read(id, buf, l)) != l) {
196 if (n == -1)
197 perror(argv[1]);
198 else
199 fprintf(stderr, "Unexpected EOF\n");
200 die("Can't read 'system'");
201 }
202 write(1, buf, l);
203 sz -= l;
204 }
205 close(id);
206 return(0);
207 }