~1K size reduction for sys.com by using Tom's talloc.c malloc/free functions

and using our own filelength for watcomc.


git-svn-id: https://svn.code.sf.net/p/freedos/svn/kernel/trunk@746 6ac86273-5f31-0410-b378-82cca8765d1b

filelist

@@ -146,6 +146,7 @@
 */*/sys/bin2c.c
 */*/sys/makefile
 */*/sys/sys.c
+*/*/sys/talloc.c
 */*/utils/echoto.bat
 */*/utils/exeflat.c
 */*/utils/indent.ini

sys/makefile

@@ -14,7 +14,8 @@ NASMFLAGS = -DSYS=1
 SYS_EXE_dependencies =  \
  sys.obj \
  fdkrncfg.obj \
- prf.obj
+ prf.obj \
+ talloc.obj
 
 #		*Explicit Rules*
 production:     bin2c.com ..\bin\sys.com
@@ -42,6 +43,8 @@ prf.obj:	..\kernel\prf.c
 
 fdkrncfg.obj:   fdkrncfg.c ..\hdr\kconfig.h
 
+talloc.obj:     talloc.c
+
 sys.com:        $(SYS_EXE_dependencies)
 		$(CL) $(CFLAGST) $(TINY) $(SYS_EXE_dependencies)
 

sys/sys.c

@@ -75,7 +75,24 @@ extern WORD CDECL sprintf(BYTE * buff, CONST BYTE * fmt, ...);
 
 #else
 
-extern long filelength(int __handle);
+long filelength(int __handle);
+#pragma aux filelength = \
+      "mov ax, 0x4202" \
+      "xor cx, cx" \
+      "xor dx, dx" \
+      "int 0x21" \
+      "push ax" \
+      "push dx" \
+      "mov ax, 0x4200" \
+      "xor cx, cx" \
+      "xor dx, dx" \
+      "int 0x21" \
+      "pop dx" \
+      "pop ax" \
+      parm [bx] \
+      modify [cx] \
+      value [dx ax];
+
 extern int unlink(const char *pathname);
 
 /* some non-conforming functions to make the executable smaller */

sys/talloc.c

@@ -0,0 +1,221 @@
+/**
+ **  TALLOC.C
+ **
+ **  lean_and_mean malloc()/free implementation
+ **  by tom ehlert, te@drivesnapshot.de
+ **
+ **  please be careful:
+ **
+ **  this is only slightly tested and has NO ERRORCHECCKING AT ALL
+ **  no internal checking. no stack checking. nothing !!
+ **
+ **  use it only, if your programs are already debugged !!
+ **/
+
+#include <stddef.h>
+#include <string.h>
+
+#ifdef __TURBOC__
+extern void *__brklvl;
+#define sbrk(x) __brklvl
+#define brk(newbrk) \
+	(((char *)(newbrk) > (char *)(&length) - 0x200) ? \
+		-1 : \
+		(__brklvl = (newbrk), 0))
+#endif
+
+#ifdef __WATCOMC__
+#include <stdlib.h>
+#define brk(newbrk) ((int)__brk((unsigned)(newbrk)))
+#endif
+
+#ifdef __GNUC__
+#include <unistd.h>
+#endif
+
+#define BUSY	    (sizeof(size_t)-1)	/* Bit set if memory block in use*/
+#define isbusy(x)   ((x->length)&BUSY)
+
+
+/**
+*** _memavl()
+***   return max. memory available
+***   Q & D
+**/
+
+#ifdef DEBUG
+extern int printf(const char *x, ...);
+#define dbprintf(x) printf x
+#else
+#define dbprintf(x)
+#endif
+/*#define printf getch() != ' ' ? exit(0) : printf*/
+
+typedef union {
+  size_t length;
+  char data[1];
+} block;
+
+void *malloc(size_t length)
+{
+  static	block *alloc_bottom = NULL;
+
+  block	*akt, *next;
+  block	*ltop = sbrk(0);
+
+  if (alloc_bottom == NULL)
+    alloc_bottom = ltop;
+
+  length = (length + sizeof(size_t) + BUSY) & ~BUSY;
+
+  akt = alloc_bottom;
+  for (;;)
+  {
+    if (akt == ltop)
+    {
+      /* end of initialized memory */
+      next = (block *)&akt->data[length];
+      if (next < akt || brk(next) == -1)
+	return NULL;
+      break;
+    }
+    dbprintf(("follow [%x] = %x\n",akt, akt->length));
+    next = (block *)(&akt->data[akt->length & ~BUSY]);
+    if (next == ltop || isbusy(akt))
+    {
+      akt = next; /* next block	 */
+    }
+    else if (isbusy(next))
+    {
+      size_t size = akt->length;
+      if (size >= length) /* try to split */
+      {
+	if (size > length) /* split */
+        {
+	  ((block *)&akt->data[length])->length =
+	    size - length;
+	}
+	break;
+      }
+      akt = next; /* next block	 */
+    }
+    else
+    {
+      /* merge 2 blocks */
+      akt->length += next->length;
+    }
+  }
+  akt->length = length | BUSY;
+  dbprintf(("set [%x] = %x\n",akt,akt->length));
+  return &akt->data[sizeof(size_t)];
+}
+
+#ifdef __WATCOMC__
+void *_nmalloc(unsigned length)
+{
+  return malloc(length);
+}
+#endif
+
+/**
+ ** reset busy-bit
+ **/
+
+void free(void *ptr)
+{
+  if (ptr)
+    ((char *) ptr)[-sizeof(size_t)] &= ~BUSY;
+}
+
+#ifdef TALLOC_NEED_REALLOC
+
+/* there isn't often need for realloc ;)
+ */
+
+void* realloc(void *ptr,size_t newlength)
+{
+  size_t oldlength = ((size_t*)ptr)[-1] & ~BUSY;
+  void *newptr;
+
+  newptr = malloc(newlength);
+
+  if (newptr == NULL)
+  {
+    if (newlength <= oldlength)
+      return ptr;
+  }
+  else
+  {
+    memcpy(newptr,ptr,oldlength);
+  }
+
+  free(ptr);
+  return newptr;
+}
+#endif
+
+#ifdef TEST
+#include <stdio.h>
+
+int gallocated = 0;
+
+void *testalloc(size_t length)
+{
+  void *p;
+
+  printf("alloc %x bytes - ",length);
+
+  p = malloc(length);
+
+  if (p) gallocated += length,printf("at %x - sum=%x\n",p,gallocated);
+  else   printf("failed\n");
+  return p;
+}
+void testfree(void* p)
+{
+  gallocated -= ((size_t*)p)[-1] & ~BUSY;
+  printf("free %x \n",p);
+
+  free(p);
+}
+
+
+
+main()
+{
+  char *s1,*s2,*s3,*s4,*s5,*s6;
+  unsigned size;
+
+  s1 = testalloc(1);
+  s2 = testalloc(2);
+  s3 = testalloc(0x10);
+  s4 = testalloc(0x100);
+  s5 = testalloc(0x1000);
+  s6 = testalloc(0xfff0);
+
+  testfree(s3);
+  s3 = testalloc(6);
+  testfree(s2);
+  testalloc(8);
+
+#ifdef __GNUC__
+  for(size = 0xe0000000; size;)
+#else
+    for(size = 0xe000; size;)
+#endif
+      {
+	if (testalloc(size))
+	  ;
+	else
+	  size >>= 1;
+      }
+
+
+  testfree(s1);
+  testfree(s5);
+  testfree(s4);
+  testfree(s6);
+
+  return 1;
+}
+#endif