Seek changes:

* merge unstable kernel optimizations
* enable seek for int2f/AX=1228
* -1 is a valid offset, so we need to process the return code seperately


git-svn-id: https://svn.code.sf.net/p/freedos/svn/kernel/trunk@1429 6ac86273-5f31-0410-b378-82cca8765d1b

hdr/sft.h

@@ -129,7 +129,7 @@ typedef struct sfttbl {
 #define SFT_FCONOUT     0x0002  /* device is console output     */
 #define SFT_FCONIN      0x0001  /* device is console input      */
 
-/* Covienence defines                                                   */
+/* Convenience defines                                                   */
 #define sft_dcb         sft_dcb_or_dev._sft_dcb
 #define sft_dev         sft_dcb_or_dev._sft_dev
 
@@ -137,3 +137,7 @@ typedef struct sfttbl {
 #define sft_flags_hi  sft_flags_union._split_sft_flags._sft_flags_hi
 #define sft_flags_lo  sft_flags_union._split_sft_flags._sft_flags_lo
 
+/* defines for LSEEK */
+#define SEEK_SET 0u
+#define SEEK_CUR 1u
+#define SEEK_END 2u

kernel/dosfns.c

@@ -305,14 +305,14 @@ long DosRWSft(int sft_idx, size_t n, void FAR * bp, int mode)
   }
 }
 
-COUNT SftSeek(int sft_idx, LONG new_pos, COUNT mode)
+COUNT SftSeek(int sft_idx, LONG new_pos, unsigned mode)
 {
   sft FAR *s = idx_to_sft(sft_idx);
   if (FP_OFF(s) == (size_t) -1)
     return DE_INVLDHNDL;
         
   /* Test for invalid mode                        */
-  if (mode < 0 || mode > 2)
+  if (mode > SEEK_END)
     return DE_INVLDFUNC;
 
   lpCurSft = s;
@@ -320,12 +320,13 @@ COUNT SftSeek(int sft_idx, LONG new_pos, COUNT mode)
   /* Do special return for character devices      */
   if (s->sft_flags & SFT_FDEVICE)
   {
-    s->sft_posit = 0l;
+    new_pos = 0;
-    return SUCCESS;
   }
-
+  else if (mode == SEEK_CUR)
-  /* seek from end of file */
+  {
-  if (mode == 2)
+    new_pos += s->sft_posit;
+  }
+  else if (mode == SEEK_END) /* seek from end of file */
   {
 /*
  *  RB list has it as Note:
@@ -339,29 +340,24 @@ COUNT SftSeek(int sft_idx, LONG new_pos, COUNT mode)
  */
     if ((s->sft_flags & SFT_FSHARED) &&
         (s->sft_mode & (O_DENYREAD | O_DENYNONE)))
-      s->sft_posit = remote_lseek(s, new_pos);
+      new_pos = remote_lseek(s, new_pos);
     else
-      s->sft_posit = s->sft_size + new_pos;
+      new_pos += s->sft_size;
   }
-  else if (mode == 0)
+
-    s->sft_posit = new_pos;
+  s->sft_posit = new_pos;
-  else /* mode == 1 */
-    s->sft_posit += new_pos;
   return SUCCESS;
 }
 
-ULONG DosSeek(unsigned hndl, LONG new_pos, COUNT mode)
+ULONG DosSeek(unsigned hndl, LONG new_pos, COUNT mode, int *rc)
 {
   int sft_idx = get_sft_idx(hndl);
-  COUNT result;
 
   /* Get the SFT block that contains the SFT      */
-  result = SftSeek(sft_idx, new_pos, mode);
+  *rc = SftSeek(sft_idx, new_pos, mode);
-  if (result == SUCCESS)
+  if (*rc == SUCCESS)
-  {
     return idx_to_sft(sft_idx)->sft_posit;
-  }
+  return *rc;
-  return (ULONG)-1;
 }
 
 STATIC long get_free_hndl(void)

kernel/inthndlr.c

@@ -931,17 +931,14 @@ dispatch:
     case 0x42:
       if (lr.AL > 2)
         goto error_invalid;
-      lrc = DosSeek(lr.BX, (LONG)((((ULONG) (lr.CX)) << 16) | lr.DX), lr.AL);
+      lrc = DosSeek(lr.BX, (LONG)((((ULONG) (lr.CX)) << 16) | lr.DX), lr.AL,
-      if (lrc == -1)
+        &rc);
-      {
+      if (rc == SUCCESS)
-        lrc = DE_INVLDHNDL;
-      }
-      else
       {
         lr.DX = (UWORD)(lrc >> 16);
-        lrc = (UWORD) lrc;
+        lr.AX = (UWORD) lrc;
       }
-      goto long_check;
+      goto short_check;
 
       /* Get/Set File Attributes                                      */
     case 0x43:
@@ -1957,19 +1954,13 @@ VOID ASMCFUNC int2F_12_handler(struct int2f12regs r)
       CritErrCode = SUCCESS;
       if (r.BP < 0x4200 || r.BP > 0x4202)
         goto error_invalid;
-#if 0
+      lrc = DosSeek(r.BX, MK_ULONG(r.CX, r.DX), r.BP & 0xff, &rc);
+      if (rc == SUCCESS)
       {
-        sft FAR *s = get_sft(r.BX);
+        r.DX = (UWORD)(lrc >> 16);
-        if ((rc = _SftSeek(s, MK_ULONG(r.CX, r.DX), r.BP & 0xff)) >= SUCCESS)
+        r.AX = (UWORD) lrc;
-        {
-          r.DX = hiword (s->sft_posit);
-          r.AX = loword (s->sft_posit);
-        }
       }
       goto short_check;
-#else
-        goto error_invalid;
-#endif
 
     case 0x29:                 /* read from file */
       r.FLAGS &= ~FLG_CARRY;

kernel/proto.h

@@ -80,14 +80,14 @@ const char FAR *get_root(const char FAR *);
 BOOL check_break(void);
 UCOUNT GenericReadSft(sft far * sftp, UCOUNT n, void FAR * bp,
                       COUNT * err, BOOL force_binary);
-COUNT SftSeek(int sft_idx, LONG new_pos, COUNT mode);
+COUNT SftSeek(int sft_idx, LONG new_pos, unsigned mode);
 /*COUNT DosRead(COUNT hndl, UCOUNT n, BYTE FAR * bp, COUNT FAR * err); */
 void BinarySftIO(int sft_idx, void *bp, int mode);
 #define BinaryIO(hndl, bp, mode) BinarySftIO(get_sft_idx(hndl), bp, mode)
 long DosRWSft(int sft_idx, size_t n, void FAR * bp, int mode);
 #define DosRead(hndl, n, bp) DosRWSft(get_sft_idx(hndl), n, bp, XFR_READ)
 #define DosWrite(hndl, n, bp) DosRWSft(get_sft_idx(hndl), n, bp, XFR_WRITE)
-ULONG DosSeek(unsigned hndl, LONG new_pos, COUNT mode);
+ULONG DosSeek(unsigned hndl, LONG new_pos, COUNT mode, int *rc);
 long DosOpen(char FAR * fname, unsigned flags, unsigned attrib);
 COUNT CloneHandle(unsigned hndl);
 long DosDup(unsigned Handle);