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                 l = strnlen((char*)buf + ib->name, bufend-t); \
  13                 if (buf[ib->name + l] != 0)                             \
  14                         buf[ib->name + l] = 0;                          \
  15                 fsize -= l;                                                             \
  16                 cbuf += l;                                                              \
  17         } else if (t > 0xa0000 && fsize > 0) {          \
  18                 strncpy((char*)cbuf, vptr(t), fsize);   \
  19                 l = strnlen((char*)cbuf, fsize);                \
  20                 if (cbuf[l] != 0)                                               \
  21                         cbuf[l] = 0;                                            \
  22                 ib->name = tsk->buf_len - fsize;                \
  23                 l++;                                                                    \
  24                 fsize -= l;                                                             \
  25                 cbuf += l;                                                              \
  26         } else {                                                                        \
  27                 ib->name = 0;                                                   \
  28         }                                                                                       \
  29         if (fsize < 0)                                                          \
  30                 fsize = 0;                                                              \
  31 }
  32
  33 int v86_task(struct uvesafb_task *tsk, u8 *buf)
  34 {
  35         u32 lbuf = 0;
  36
  37         ulog(LOG_DEBUG, "task flags: 0x%02x\n", tsk->flags);
  38         ulog(LOG_DEBUG, "EAX=0x%08x EBX=0x%08x ECX=0x%08x EDX=0x%08x\n",
  39                  tsk->regs.eax, tsk->regs.ebx, tsk->regs.ecx, tsk->regs.edx);
  40         ulog(LOG_DEBUG, "ESP=0x%08x EBP=0x%08x ESI=0x%08x EDI=0x%08x\n",
  41                  tsk->regs.esp, tsk->regs.ebp, tsk->regs.esi, tsk->regs.edi);
  42
  43         /* Get the VBE Info Block */
  44         if (tsk->flags & TF_VBEIB) {
  45                 struct vbe_ib *ib;
  46                 int fsize;
  47                 u32 t, bufend;
  48                 u16 *td;
  49                 u8 *cbuf;
  50
  51                 lbuf = v86_mem_alloc(tsk->buf_len);
  52                 if (!lbuf) {
  53                         ulog(LOG_ERR, "Memory allocation for a VBE IB buffer failed.");
  54                         return -1;
  55                 }
  56                 memcpy(vptr(lbuf), buf, tsk->buf_len);
  57                 tsk->regs.es  = lbuf >> 4;
  58                 tsk->regs.edi = 0x0000;
  59
  60                 if (v86_int(0x10, &tsk->regs) || (tsk->regs.eax & 0xffff) != 0x004f)
  61                         goto out_vbeib;
  62
  63                 ib = (struct vbe_ib*)buf;
  64                 bufend = lbuf + sizeof(*ib);
  65                 memcpy(buf, vptr(lbuf), tsk->buf_len);
  66
  67                 /* The original VBE Info Block is 512 bytes long. */
  68                 fsize = tsk->buf_len - 512;
  69                 cbuf = buf + 512;
  70
  71                 t = addr(ib->mode_list_ptr);
  72                 /* Mode list is in the buffer, we're good. */
  73                 if (t < bufend) {
  74                         ulog(LOG_DEBUG, "The mode list is in the buffer at %.8x.", t);
  75                         ib->mode_list_ptr = t - lbuf;
  76                         td = (u16*) (buf + ib->mode_list_ptr);
  77
  78                         while (fsize > 2 && *td != 0xffff) {
  79                                 td++;
  80                                 t += 2;
  81                                 fsize -= 2;
  82                                 cbuf += 2;
  83                         }
  84
  85                         *td = 0xffff;
  86                         cbuf += 2;
  87                         fsize -= 2;
  88
  89                 /* Mode list is in the ROM. We copy as much of it as we can
  90                  * to the task buffer. */
  91                 } else if (t > 0xa0000) {
  92                         u16 tmp;
  93
  94                         ulog(LOG_DEBUG, "The mode list is in the Video ROM at %.8x", t);
  95
  96                         td = (u16*)cbuf;
  97
  98                         while (fsize > 2 && (tmp = v_rdw(t)) != 0xffff) {
  99                                 fsize -= 2;
 100                                 *td = tmp;
 101                                 td++;
 102                                 t += 2;
 103                                 cbuf += 2;
 104                         }
 105
 106                         ib->mode_list_ptr = 512;
 107                         *td = 0xffff;
 108                         cbuf += 2;
 109                         fsize -= 2;
 110
 111                 /* Mode list is somewhere else. We're seriously screwed. */
 112                 } else {
 113                         ulog(LOG_ERR, "Can't retrieve mode list from %x\n", t);
 114                         ib->mode_list_ptr = 0;
 115                 }
 116
 117                 vbeib_get_string(oem_string_ptr);
 118                 vbeib_get_string(oem_vendor_name_ptr);
 119                 vbeib_get_string(oem_product_name_ptr);
 120                 vbeib_get_string(oem_product_rev_ptr);
 121 out_vbeib:
 122                 v86_mem_free(lbuf);
 123         } else {
 124                 if (tsk->buf_len) {
 125                         lbuf = v86_mem_alloc(tsk->buf_len);
 126                         if (!lbuf) {
 127                                 ulog(LOG_ERR, "Memory allocation for a v86d task buffer failed.");
 128                                 return -1;
 129                         }
 130                         memcpy(vptr(lbuf), buf, tsk->buf_len);
 131                 }
 132
 133                 if (tsk->flags & TF_BUF_ESDI) {
 134                         tsk->regs.es = lbuf >> 4;
 135                         tsk->regs.edi = 0x0000;
 136                 }
 137
 138                 if (tsk->flags & TF_BUF_ESBX) {
 139                         tsk->regs.es = lbuf >> 4;
 140                         tsk->regs.ebx = 0x0000;
 141                 }
 142
 143                 if (v86_int(0x10, &tsk->regs) || (tsk->regs.eax & 0xffff) != 0x004f)
 144                         goto out;
 145
 146                 if (tsk->buf_len && tsk->flags & TF_BUF_RET) {
 147                         memcpy(buf, vptr(lbuf), tsk->buf_len);
 148                 }
 149 out:
 150                 if (tsk->buf_len)
 151                         v86_mem_free(lbuf);
 152         }
 153
 154         return 0;
 155 }
 156