v86_common.c

   1 #include <string.h>
   2 #include "v86.h"
   3
   4 #define addr(t) (((t & 0xffff0000) >> 12) + (t & 0x0000ffff))
   5
   6 #define vbeib_get_string(name)                                  \
   7 {                                                                                               \
   8         int l;                                                                          \
   9         t = addr(ib->name);                                                     \
  10         if (t < bufend) {                                                       \
  11                 ib->name = t - lbuf;                                    \
  12         } else if (t > 0xa0000 && fsize > 0) {          \
  13                 strncpy((char*)buf, vptr(t), fsize);    \
  14                 ib->name = tsk->buf_len - fsize;                \
  15                 l = strlen((char*)buf);                                 \
  16                 fsize -= l;                                                             \
  17                 buf += l;                                                               \
  18                 if (fsize < 0)                                                  \
  19                         fsize = 0;                                                      \
  20         } else {                                                                        \
  21                 ib->name = 0;                                                   \
  22         }                                                                                       \
  23 }
  24
  25 int v86_task(struct uvesafb_task *tsk, u8 *buf)
  26 {
  27         u32 lbuf = 0;
  28
  29         /* Get the VBE Info Block */
  30         if (tsk->flags & TF_VBEIB) {
  31                 struct vbe_ib *ib;
  32                 int fsize;
  33                 u32 t, bufend;
  34                 u16 *td;
  35
  36                 lbuf = v86_mem_alloc(tsk->buf_len);
  37                 memcpy(vptr(lbuf), buf, tsk->buf_len);
  38                 tsk->regs.es  = lbuf >> 4;
  39                 tsk->regs.edi = 0x0000;
  40
  41                 if (v86_int(0x10, &tsk->regs) || (tsk->regs.eax & 0xffff) != 0x004f)
  42                         goto out_vbeib;
  43
  44                 ib = (struct vbe_ib*)buf;
  45                 bufend = lbuf + sizeof(*ib);
  46                 memcpy(buf, vptr(lbuf), tsk->buf_len);
  47
  48                 /* The original VBE Info Block is 512 bytes long. */
  49                 fsize = tsk->buf_len - 512;
  50
  51                 t = addr(ib->mode_list_ptr);
  52                 /* Mode list is in the buffer, we're good. */
  53                 if (t < bufend) {
  54                         ib->mode_list_ptr = t - lbuf;
  55
  56                 /* Mode list is in the ROM. We copy as much of it as we can
  57                  * to the task buffer. */
  58                 } else if (t > 0xa0000) {
  59                         u16 tmp;
  60
  61                         td = (u16*) (buf + 512);
  62
  63                         while (fsize > 2 && (tmp = v_rdw(t)) != 0xffff) {
  64                                 fsize -= 2;
  65                                 *td = tmp;
  66                                 t += 2;
  67                                 td++;
  68                         }
  69
  70                         ib->mode_list_ptr = 512;
  71                         *td = 0xffff;
  72
  73                 /* Mode list is somewhere else. We're seriously screwed. */
  74                 } else {
  75                         ulog("Can't retrieve mode list from %x\n", t);
  76                         ib->mode_list_ptr = 0;
  77                 }
  78
  79                 buf += 512;
  80
  81                 vbeib_get_string(oem_string_ptr);
  82                 vbeib_get_string(oem_vendor_name_ptr);
  83                 vbeib_get_string(oem_product_name_ptr);
  84                 vbeib_get_string(oem_product_rev_ptr);
  85 out_vbeib:
  86                 v86_mem_free(lbuf);
  87         } else {
  88                 if (tsk->buf_len) {
  89                         lbuf = v86_mem_alloc(tsk->buf_len);
  90                         memcpy(vptr(lbuf), buf, tsk->buf_len);
  91                 }
  92
  93                 if (tsk->flags & TF_BUF_ESDI) {
  94                         tsk->regs.es = lbuf >> 4;
  95                         tsk->regs.edi = 0x0000;
  96                 }
  97
  98                 if (tsk->flags & TF_BUF_ESBX) {
  99                         tsk->regs.es = lbuf >> 4;
 100                         tsk->regs.ebx = 0x0000;
 101                 }
 102
 103                 if (v86_int(0x10, &tsk->regs) || (tsk->regs.eax & 0xffff) != 0x004f)
 104                         goto out;
 105
 106                 if (tsk->buf_len && tsk->flags & TF_BUF_RET) {
 107                         memcpy(buf, vptr(lbuf), tsk->buf_len);
 108                 }
 109 out:
 110                 if (tsk->buf_len)
 111                         v86_mem_free(lbuf);
 112         }
 113
 114         return 0;
 115 }
 116