refactor malloc's expand_heap to share with __simple_malloc

[musl] / src / malloc / lite_malloc.c

diff --git a/src/malloc/lite_malloc.c b/src/malloc/lite_malloc.c
index 7643fc2..008549d 100644 (file)
--- a/src/malloc/lite_malloc.c
+++ b/src/malloc/lite_malloc.c
@@ -4,43 +4,46 @@
 #include <errno.h>
 #include "libc.h"
 
-uintptr_t __brk(uintptr_t);
-
 #define ALIGN 16
 
+void *__expand_heap(size_t *);
+
 void *__simple_malloc(size_t n)
 {
-       static uintptr_t cur, brk;
-       uintptr_t base, new;
+       static char *cur, *end;
        static volatile int lock[2];
-       size_t align=1;
+       size_t align=1, pad;
+       void *p;
 
        if (!n) n++;
-       if (n > SIZE_MAX/2) goto toobig;
-
        while (align<n && align<ALIGN)
                align += align;
-       n = n + align - 1 & -align;
 
        LOCK(lock);
-       if (!cur) cur = brk = __brk(0)+16;
-       base = cur + align-1 & -align;
-       if (n > SIZE_MAX - PAGE_SIZE - base) goto fail;
-       if (base+n > brk) {
-               new = base+n + PAGE_SIZE-1 & -PAGE_SIZE;
-               if (__brk(new) != new) goto fail;
-               brk = new;
-       }
-       cur = base+n;
-       UNLOCK(lock);
 
-       return (void *)base;
+       pad = -(uintptr_t)cur & align-1;
+
+       if (n <= SIZE_MAX/2 + ALIGN) n += pad;
+
+       if (n > end-cur) {
+               size_t m = n;
+               char *new = __expand_heap(&m);
+               if (!new) {
+                       UNLOCK(lock);
+                       return 0;
+               }
+               if (new != end) {
+                       cur = new;
+                       n -= pad;
+                       pad = 0;
+               }
+               end = new + m;
+       }
 
-fail:
+       p = cur + pad;
+       cur += n;
        UNLOCK(lock);
-toobig:
-       errno = ENOMEM;
-       return 0;
+       return p;
 }
 
 weak_alias(__simple_malloc, malloc);