sys/src/boot/pc/sub.c

   1 #include <u.h>
   2 #include <a.out.h>
   3 #include "fns.h"
   4 #include "mem.h"
   5
   6 void
   7 memset(void *p, int v, int n)
   8 {
   9         uchar *d = p;
  10         while(n > 0){
  11                 *d++ = v;
  12                 n--;
  13         }
  14 }
  15
  16 void
  17 memmove(void *dst, void *src, int n)
  18 {
  19         uchar *d = dst;
  20         uchar *s = src;
  21
  22         if(d < s){
  23                 while(n > 0){
  24                         *d++ = *s++;
  25                         n--;
  26                 }
  27         } if(d > s){
  28                 s += n;
  29                 d += n;
  30                 while(n > 0){
  31                         *--d = *--s;
  32                         n--;
  33                 }
  34         }
  35 }
  36
  37 int
  38 memcmp(void *src, void *dst, int n)
  39 {
  40         uchar *d = dst;
  41         uchar *s = src;
  42         int r = 0;
  43         while((n > 0) && (r = (*d++ - *s++)) == 0)
  44                 n--;
  45         return r;
  46 }
  47
  48 int
  49 strlen(char *s)
  50 {
  51         char *p = s;
  52         while(*p)
  53                 p++;
  54         return p - s;
  55 }
  56
  57 char*
  58 strchr(char *s, int c)
  59 {
  60         for(; *s; s++)
  61                 if(*s == c)
  62                         return s;
  63         return 0;
  64 }
  65
  66 char*
  67 strrchr(char *s, int c)
  68 {
  69         char *r;
  70         r = 0;
  71         while(s = strchr(s, c))
  72                 r = s++;
  73         return r;
  74 }
  75
  76 void
  77 print(char *s)
  78 {
  79         while(*s)
  80                 putc(*s++);
  81 }
  82
  83 int
  84 readn(void *f, void *data, int len)
  85 {
  86         uchar *p, *e;
  87
  88         p = data;
  89         e = p + len;
  90         while(p < e){
  91                 if((len = read(f, p, e - p)) <= 0)
  92                         break;
  93                 p += len;
  94         }
  95         return p - (uchar*)data;
  96 }
  97
  98 static int
  99 readline(void *f, char buf[64])
 100 {
 101         static char white[] = "\t ";
 102         char *p;
 103
 104         p = buf;
 105         do{
 106                 if(!f)
 107                         putc('>');
 108                 while(p < buf + 64-1){
 109                         if(!f){
 110                                 putc(*p = getc());
 111                                 if(*p == '\r')
 112                                         putc('\n');
 113                                 else if(*p == 0x08 && p > buf){
 114                                         p--;
 115                                         continue;
 116                                 }
 117                         }else if(read(f, p, 1) <= 0)
 118                                 return 0;
 119                         if(p == buf && strchr(white, *p))
 120                                 continue;
 121                         if(strchr(crnl, *p))
 122                                 break;
 123                         p++;
 124                 }
 125                 while(p > buf && strchr(white, p[-1]))
 126                         p--;
 127         }while(p == buf);
 128         *p = 0;
 129         return p - buf;
 130 }
 131
 132 static int
 133 timeout(int ms)
 134 {
 135         while(ms > 0){
 136                 if(gotc())
 137                         return 1;
 138                 usleep(100000);
 139                 ms -= 100;
 140         }
 141         return 0;
 142 }
 143
 144 #define BOOTLINE        ((char*)CONFADDR)
 145 #define BOOTLINELEN     64
 146 #define BOOTARGS        ((char*)(CONFADDR+BOOTLINELEN))
 147 #define BOOTARGSLEN     (4096-0x200-BOOTLINELEN)
 148
 149 char *confend;
 150
 151 static void apmconf(int);
 152
 153 char*
 154 configure(void *f, char *path)
 155 {
 156         char line[64], *kern, *p;
 157         int inblock, n;
 158 Clear:
 159         kern = 0;
 160         inblock = 0;
 161
 162         confend = (char*)BOOTARGS;
 163         memset(confend, 0, BOOTARGSLEN);
 164 Loop:
 165         while((n = readline(f, line)) > 0){
 166                 if(*line == 0 || strchr("#;=", *line))
 167                         continue;
 168                 if(*line == '['){
 169                         inblock = memcmp("[common]", line, 8);
 170                         continue;
 171                 }
 172                 if(!memcmp("clear", line, 6)){
 173                         print("ok\r\n");
 174                         goto Clear;
 175                 }
 176                 if(!memcmp("boot", line, 5))
 177                         break;
 178                 if(inblock || !strrchr(line, '='))
 179                         continue;
 180                 if(!memcmp("bootfile=", line, 9))
 181                         memmove(kern = path, line+9, 1 + n-9);
 182                 if(!memcmp("apm", line, 3) && line[4]=='='){
 183                         apmconf('0' - line[3]);
 184                         continue;
 185                 }
 186                 memmove(confend, line, n); confend += n;
 187                 *confend++ = '\n';
 188                 print(line); print(crnl);
 189         }
 190         *confend = 0;
 191
 192         if(f){
 193                 close(f);
 194                 f = 0;
 195
 196                 if(kern && timeout(500))
 197                         goto Loop;
 198         }
 199
 200         if(!kern){
 201                 print("no bootfile\r\n");
 202                 goto Loop;
 203         }
 204         if(p = strrchr(kern, '!'))
 205                 kern = p+1;
 206
 207         return kern;
 208 }
 209
 210
 211 static ushort
 212 beswab(ushort s)
 213 {
 214         uchar *p;
 215
 216         p = (uchar*)&s;
 217         return (p[0]<<8) | p[1];
 218 }
 219
 220 static ulong
 221 beswal(ulong l)
 222 {
 223         uchar *p;
 224
 225         p = (uchar*)&l;
 226         return (p[0]<<24) | (p[1]<<16) | (p[2]<<8) | p[3];
 227 }
 228
 229 static void
 230 hexfmt(char *s, int i, ulong a)
 231 {
 232         s += i;
 233         while(i > 0){
 234                 *--s = hex[a&15];
 235                 a >>= 4;
 236                 i--;
 237         }
 238 }
 239
 240 static void
 241 addconfx(char *s, int w, ulong v)
 242 {
 243         int n;
 244
 245         n = strlen(s);
 246         memmove(confend, s, n);
 247         hexfmt(confend+n, w, v);
 248         confend += n+w;
 249         *confend = 0;
 250 }
 251
 252 void apm(int id);
 253
 254 static void
 255 apmconf(int id)
 256 {
 257         uchar *a;
 258         char *s;
 259
 260         a = (uchar*)CONFADDR;
 261         memset(a, 0, 20);
 262
 263         apm(id);
 264         if(memcmp(a, "APM", 4))
 265                 return;
 266
 267         s = confend;
 268
 269         addconfx("apm", 1, id);
 270         addconfx("=ax=", 4, *((ushort*)(a+4)));
 271         addconfx(" ebx=", 8, *((ulong*)(a+12)));
 272         addconfx(" cx=", 4, *((ushort*)(a+6)));
 273         addconfx(" dx=", 4, *((ushort*)(a+8)));
 274         addconfx(" di=", 4, *((ushort*)(a+10)));
 275         addconfx(" esi=", 8, *((ulong*)(a+16)));
 276
 277         print(s); print(crnl);
 278
 279         *confend++ = '\n';
 280 }
 281
 282 ulong e820(ulong bx, void *p);
 283
 284 static void
 285 e820conf(void)
 286 {
 287         struct {
 288                 uvlong  base;
 289                 uvlong  len;
 290                 ulong   typ;
 291                 ulong   ext;
 292         } e;
 293         uvlong v;
 294         ulong bx;
 295         char *s;
 296
 297         memset(&e, 0, sizeof(e));
 298         if((bx = e820(0, &e)) == 0)
 299                 return;
 300
 301         s = confend;
 302         memmove(confend, "e820=", 5);
 303         confend += 5;
 304
 305         do{
 306                 if(e.typ == 1 && (e.ext & 1) == 0 && e.len){
 307                         v = e.base;
 308                         addconfx("", 8, v>>32);
 309                         addconfx("", 8, v&0xffffffff);
 310                         v = e.base + e.len;
 311                         addconfx(" ", 8, v>>32);
 312                         addconfx("", 8, v&0xffffffff);
 313                         *confend++ = ' ';
 314                 }
 315
 316                 memset(&e, 0, sizeof(e));
 317         } while(bx = e820(bx, &e));
 318
 319         *confend = 0;
 320         print(s); print(crnl);
 321
 322         *confend++ = '\n';
 323 }
 324
 325 void a20(void);
 326
 327 char*
 328 bootkern(void *f)
 329 {
 330         uchar *e, *d, *t;
 331         ulong n;
 332         Exec ex;
 333
 334         e820conf();
 335
 336         a20();
 337         if(readn(f, &ex, sizeof(ex)) != sizeof(ex))
 338                 return "bad header";
 339         if(beswal(ex.magic) != I_MAGIC)
 340                 return "bad magic";
 341
 342         e = (uchar*)(beswal(ex.entry) & ~0xF0000000UL);
 343         t = e;
 344         n = beswal(ex.text);
 345         if(readn(f, t, n) != n)
 346                 goto Error;
 347         d = (uchar*)PGROUND((ulong)t + n);
 348         n = beswal(ex.data);
 349         if(readn(f, d, n) != n)
 350                 goto Error;
 351         close(f);
 352         unload();
 353         memset(BOOTLINE, 0, BOOTLINELEN);
 354         jump(e);
 355 Error:
 356         return "i/o error";
 357 }