random kernel stuff

[polintos/scott/priv.git] / kernel / lib / libc.cc

diff --git a/kernel/lib/libc.cc b/kernel/lib/libc.cc
index f03c17c00f8163551b8a5aa6e5846dced70ddc62..e571384048458bf9d9ee49e0e593900affd30fe4 100644 (file)
--- a/kernel/lib/libc.cc
+++ b/kernel/lib/libc.cc
@@ -2,23 +2,15 @@
 //
 // This software is copyright (c) 2006 Scott Wood <scott@buserror.net>.
 // 
-// Permission is hereby granted, free of charge, to any person obtaining a copy of
-// this software and associated documentation files (the "Software"), to deal with
-// the Software without restriction, including without limitation the rights to
-// use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
-// of the Software, and to permit persons to whom the Software is furnished to do
-// so, subject to the following condition:
+// This software is provided 'as-is', without any express or implied warranty.
+// In no event will the authors or contributors be held liable for any damages
+// arising from the use of this software.
 // 
-// The above copyright notice and this permission notice shall be
-// included in all copies or substantial portions of the Software.
-// 
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
-// FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
-// CONTRIBUTORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS WITH THE
-// SOFTWARE.
+// Permission is hereby granted to everyone, free of charge, to use, copy,
+// modify, prepare derivative works of, publish, distribute, perform,
+// sublicense, and/or sell copies of the Software, provided that the above
+// copyright notice and disclaimer of warranty be included in all copies or
+// substantial portions of this software.
 
 
 #include <kern/types.h>
@@ -547,6 +539,8 @@ void *memset(void *b, int ch, size_t len)
 
 void *malloc(size_t len)
 {
+       assert(len <= Arch::page_size - sizeof(size_t));
+
        len = (len + sizeof(size_t) + Arch::page_size - 1) / Arch::page_size;
        Mem::Page *page = Mem::PageAlloc::alloc(len);
        
@@ -559,8 +553,7 @@ void *malloc(size_t len)
 void free(void *addr)
 {
        if (addr) {
-               size_t *ptr = (size_t *)addr;
-               ptr--;
+               size_t *ptr = (size_t *)addr - 1;
                size_t len = *ptr;
                Mem::Page *page = Mem::kvirt_to_page(addr);
                Mem::PageAlloc::free(page, len);