Honour malloc_junk ('J') with realloc(3), and fix page_dir shrink update.

1 files changed, 11 insertions, 6 deletions

diff --git a/src/lib/libc/stdlib/malloc.c b/src/lib/libc/stdlib/malloc.c
index 45a8cc8182..9ab3deb5df 100644
--- a/src/lib/libc/stdlib/malloc.c
+++ b/src/lib/libc/stdlib/malloc.c
@@ -8,7 +8,7 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
-static char rcsid[] = "$OpenBSD: malloc.c,v 1.52 2002/11/25 00:06:51 cloder Exp $";
+static char rcsid[] = "$OpenBSD: malloc.c,v 1.53 2002/11/27 21:40:32 tdeval Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 /*
@@ -893,10 +893,12 @@ irealloc(ptr, size)
         for (osize = malloc_pagesize; *++mp == MALLOC_FOLLOW;)
             osize += malloc_pagesize;
 
-        if (!malloc_realloc &&                  /* unless we have to, */
+        if (!malloc_realloc &&                  /* Unless we have to, */
           size <= osize &&                      /* .. or are too small, */
           size > (osize - malloc_pagesize)) {   /* .. or can free a page, */
-            return ptr;                         /* don't do anything. */
+            if (malloc_junk)
+                memset((char *)ptr + size, SOME_JUNK, osize-size);
+            return ptr;                         /* ..don't do anything else. */
         }
 
     } else if (*mp >= MALLOC_MAGIC) {           /* Chunk allocation */
@@ -919,10 +921,12 @@ irealloc(ptr, size)
         osize = (*mp)->size;
 
         if (!malloc_realloc &&          /* Unless we have to, */
-          size < osize &&               /* ..or are too small, */
+          size <= osize &&              /* ..or are too small, */
           (size > osize/2 ||            /* ..or could use a smaller size, */
           osize == malloc_minsize)) {   /* ..(if there is one) */
-            return ptr;                 /* ..Don't do anything */
+            if (malloc_junk)
+                memset((char *)ptr + size, SOME_JUNK, osize-size);
+            return ptr;                 /* ..don't do anything else. */
         }
 
     } else {
@@ -1070,11 +1074,12 @@ free_pages(ptr, index, info)
         malloc_brk = pf->end;
 
         index = ptr2index(pf->end);
-        last_index = index - 1;
 
         for(i=index;i <= last_index;)
             page_dir[i++] = MALLOC_NOT_MINE;
 
+        last_index = index - 1;
+
         /* XXX: We could realloc/shrink the pagedir here I guess. */
     }
     if (pt)