v86_common.c

   1 #include "v86.h"
   2
   3 #define addr(t) (((t & 0xffff0000) >> 12) + (t & 0x0000ffff))
   4
   5 #define vbeib_get_string(name)                                  \
   6 {                                                                                               \
   7         int l;                                                                          \
   8         t = addr(ib->name);                                                     \
   9         if (t < bufend) {                                                       \
  10                 ib->name = t - (u32)lbuf;                               \
  11         } else if (t > 0xa0000 && fsize > 0) {          \
  12                 strncpy((char*)buf, (char*)t, fsize);   \
  13                 ib->name = tsk->buf_len - fsize;                \
  14                 l = strlen((char*)t);                                   \
  15                 fsize -= l;                                                             \
  16                 buf += l;                                                               \
  17                 if (fsize < 0)                                                  \
  18                         fsize = 0;                                                      \
  19         } else {                                                                        \
  20                 ib->name = 0;                                                   \
  21         }                                                                                       \
  22 }
  23
  24 int v86_task(struct uvesafb_task *tsk, u8 *buf)
  25 {
  26         u8 *lbuf = NULL;
  27
  28         /* Get the VBE Info Block */
  29         if (tsk->flags & TF_VBEIB) {
  30                 struct vbe_ib *ib;
  31                 int fsize;
  32                 u32 t, bufend;
  33                 u16 *ts, *td;
  34
  35                 lbuf = v86_mem_alloc(tsk->buf_len);
  36                 memcpy(lbuf, buf, tsk->buf_len);
  37                 tsk->regs.es  = (u32)lbuf >> 4;
  38                 tsk->regs.edi = 0x0000;
  39
  40                 if (v86_int(0x10, &tsk->regs) || (tsk->regs.eax & 0xffff) != 0x004f)
  41                         goto out_vbeib;
  42
  43                 ib = (struct vbe_ib*)buf;
  44                 bufend = (u32)(lbuf + sizeof(*ib));
  45                 memcpy(buf, lbuf, tsk->buf_len);
  46
  47                 /* The original VBE Info Block is 512 bytes long. */
  48                 fsize = tsk->buf_len - 512;
  49
  50                 t = addr(ib->mode_list_ptr);
  51                 /* Mode list is in the buffer, we're good. */
  52                 if (t < bufend) {
  53                         ib->mode_list_ptr = t - (u32)lbuf;
  54
  55                 /* Mode list is in the ROM. We copy as much of it as we can
  56                  * to the task buffer. */
  57                 } else if (t > 0xa0000) {
  58                         ts = (u16*) t;
  59                         td = (u16*) (buf + 512);
  60
  61                         while (fsize > 2 && *ts != 0xffff) {
  62                                 fsize -= 2;
  63                                 *td = *ts;
  64                                 ts++;
  65                                 td++;
  66                         }
  67
  68                         ib->mode_list_ptr = 512;
  69                         *td = 0xffff;
  70
  71                 /* Mode list is somewhere else. We're seriously screwed. */
  72                 } else {
  73                         ulog("Can't retrieve mode list from %x\n", t);
  74                         ib->mode_list_ptr = 0;
  75                 }
  76
  77                 buf += 512;
  78
  79                 vbeib_get_string(oem_string_ptr);
  80                 vbeib_get_string(oem_vendor_name_ptr);
  81                 vbeib_get_string(oem_product_name_ptr);
  82                 vbeib_get_string(oem_product_rev_ptr);
  83 out_vbeib:
  84                 v86_mem_free(lbuf);
  85         } else {
  86                 if (tsk->buf_len) {
  87                         lbuf = v86_mem_alloc(tsk->buf_len);
  88                         memcpy(lbuf, buf, tsk->buf_len);
  89                 }
  90
  91                 if (tsk->flags & TF_BUF_ESDI) {
  92                         tsk->regs.es = (u32)lbuf >> 4;
  93                         tsk->regs.edi = 0x0000;
  94                 }
  95
  96                 if (tsk->flags & TF_BUF_ESBX) {
  97                         tsk->regs.es = (u32)lbuf >> 4;
  98                         tsk->regs.ebx = 0x0000;
  99                 }
 100
 101                 if (v86_int(0x10, &tsk->regs) || (tsk->regs.eax & 0xffff) != 0x004f)
 102                         goto out;
 103
 104                 if (tsk->buf_len && tsk->flags & TF_BUF_RET) {
 105                         memcpy(buf, lbuf, tsk->buf_len);
 106                 }
 107 out:
 108                 if (tsk->buf_len)
 109                         v86_mem_free(lbuf);
 110         }
 111
 112         return 0;
 113 }
 114