[libc] More memory allocation changes for 8086 toolchain

elkscmd/tui/Makefile

@@ -13,7 +13,7 @@ PRGS = fm matrix cons ttyinfo sl ttyclock ttypong ttytetris invaders
 #PRGS_HOST =
 
 TUILIB = tty.o runes.o unikey.o
-MALLOC=../../libc/malloc/v7malloc.o
+MALLOC=v7stub.o
 
 all: $(PRGS) $(PRGS_HOST)
 

elkscmd/tui/v7stub.c

@@ -0,0 +1,17 @@
+/* stub to force inclusion of debug malloc (v7) */
+#include <stdlib.h>
+
+void *malloc(size_t size)
+{
+    return __dmalloc(size);
+}
+
+void free(void *ptr)
+{
+    __dfree(ptr);
+}
+
+void *realloc(void *ptr, size_t size)
+{
+    return __drealloc(ptr, size);
+}

libc/include/malloc.h

@@ -4,26 +4,26 @@
 #include <sys/types.h>
 
 /* default malloc (dev86) */
-void  *malloc(size_t);
-void   free(void *);
-size_t malloc_usable_size(void *);
+void   *malloc(size_t);
+void   *realloc(void *, size_t);
+void    free(void *);
+size_t  malloc_usable_size(void *);
 
 /* debug malloc (v7 malloc) */
-void  *__dmalloc(size_t);
-void  *__drealloc(void *, size_t);
-void   __dfree(void *);
-size_t __dmalloc_usable_size(void *);
+void   *__dmalloc(size_t);
+void   *__drealloc(void *, size_t);
+void    __dfree(void *);
+size_t  __dmalloc_usable_size(void *);
 
 /* arena malloc (64k near/unlimited far heap) */
-void  *__amalloc(size_t);
-int    __amalloc_add_heap(char __far *start, size_t size);
-void  *__arealloc(void *, size_t);       /* NYI */
-void   __afree(void *);
-size_t __dmalloc_usable_size(void *);
+void   *__amalloc(size_t);
+int     __amalloc_add_heap(char __far *start, size_t size);
+void   *__arealloc(void *, size_t);         /* not implemented */
+void    __afree(void *);
+size_t  __amalloc_usable_size(void *);
 
 /* usable with all mallocs */
-void  *realloc(void *, size_t);
-void  *calloc(size_t elm, size_t sz);
+void   *calloc(size_t elm, size_t sz);
 
 /* alloc/free from main memory */
 void __far *fmemalloc(unsigned long size);
@@ -32,4 +32,7 @@ int         fmemfree(void __far *ptr);
 int        _fmemalloc(int paras, unsigned short *pseg); /* syscall */
 int        _fmemfree(unsigned short seg);               /* syscall */
 
+extern unsigned int malloc_arena_size;
+extern unsigned int malloc_arena_thresh;
+
 #endif

libc/malloc/Makefile

@@ -17,6 +17,7 @@ CFLAGS	+= -DMCHUNK=16
 # default malloc (dev86)
 DEFAULT_MALLOC_OBJS = \
 	malloc.o \
+	realloc.o \
 	free.o \
 	__mini_malloc.o \
 	__alloca_alloc.o \
@@ -32,7 +33,6 @@ ARENA_MALLOC_OBJS = amalloc.o
 
 # these objects work with any malloc
 OBJS = \
-	realloc.o \
 	calloc.o \
 	brk.o \
 	sbrk.o \

libc/malloc/amalloc.c

@@ -238,7 +238,8 @@ __afree(void *ptr)
 
     if (p == NULL)
         return;
-    debug("(%d)  free(%d) = %04x\n", getpid(), (unsigned)(p[-1].ptr - p) << 1, p-1);
+    debug("(%d)  free(%d) = %04x\n", getpid(),
+        (unsigned)(next(p-1) - p) * sizeof(union store), p-1);
     ASSERT(FP_SEG(ptr)==allocseg);
     ASSERT(p>clearbusy(allocs[allocsize-1].ptr)&&p<=alloct);
     ASSERT(malloc_check_heap());
@@ -253,7 +254,7 @@ size_t __amalloc_usable_size(void *ptr)
 {
     NPTR p = (NPTR)ptr;
 
-    if (p == NULL)
+    if (p == NULL)          /* NOTE this allows fmemalloc pointers to return 0 here */
         return 0;
     ASSERT(FP_SEG(ptr)==allocseg);
     ASSERT(p>clearbusy(allocs[allocsize-1].ptr)&&p<=alloct);
@@ -280,10 +281,10 @@ __arealloc(void *ptr, size_t nbytes)
         return __amalloc(nbytes);
     debug("(%d)realloc(%04x,%u) ", getpid(), (unsigned)(p-1), nbytes);
 
-    ASSERT(testbusy(p[-1].ptr));
-    if(testbusy(p[-1].ptr))
-        free(p);
-    onw = p[-1].ptr - p;
+    ASSERT(testbusy(next(p-1)));
+    if(testbusy(next(p-1)))
+        __afree(p);
+    onw = next(p-1) - p;
     q = (NPTR)__amalloc(nbytes);   // FIXME and also use memcpy
     if(q==NULL || q==p)
         return((void *)q);

libc/malloc/realloc.c

@@ -1,7 +1,6 @@
 #include <malloc.h>
 #include <string.h>
 
-/* this realloc usable with all malloc allocators */
 void *realloc(void *ptr, size_t size)
 {
 	void *nptr;
@@ -11,15 +10,17 @@ void *realloc(void *ptr, size_t size)
 		return malloc(size);
 
 	osize = malloc_usable_size(ptr);
-#if LATER
+#if 0
 	if (size <= osize)
-		return ptr;
+		return ptr;         /* don't reallocate, do nothing */
+#else
+	if (size <= osize)
+        osize = size;       /* copy less bytes in memcpy below */
 #endif
 
 	nptr = malloc(size);
 	if (nptr == 0)
 		return 0;
-
 	memcpy(nptr, ptr, osize);
 	free(ptr);
 

libc/malloc/v7malloc.c

@@ -217,7 +217,8 @@ __dfree(void *ptr)
 
     if (p == NULL)
         return;
-    debug("(%d)  free(%d) = %04x\n", getpid(), (unsigned)(p[-1].ptr - p) << 1, p-1);
+    debug("(%d)  free(%d) = %04x\n", getpid(),
+        (unsigned)(next(p-1) - p) * sizeof(union store), p-1);
     ASSERT(p>clearbusy(allocs[SIZE-1].ptr)&&p<=alloct);
     ASSERT(malloc_check_heap());
     allocp = --p;
@@ -256,10 +257,10 @@ __drealloc(void *ptr, size_t nbytes)
         return __dmalloc(nbytes);
     debug("(%d)realloc(%04x,%u) ", getpid(), (unsigned)(p-1), nbytes);
 
-    ASSERT(testbusy(p[-1].ptr));
-    if(testbusy(p[-1].ptr))
-        free(p);
-    onw = p[-1].ptr - p;
+    ASSERT(testbusy(next(p-1)));
+    if(testbusy(next(p-1)))
+        __dfree(p);
+    onw = next(p-1) - p;
     q = (NPTR)__dmalloc(nbytes);   // FIXME and also use memcpy
     if(q==NULL || q==p)
         return((void *)q);