summaryrefslogtreecommitdiff
path: root/libc/stdlib/malloc-simple
diff options
context:
space:
mode:
authorEric Andersen <andersen@codepoet.org>2003-12-30 01:41:14 +0000
committerEric Andersen <andersen@codepoet.org>2003-12-30 01:41:14 +0000
commit4c9086ee4afde4257a4b4a8f55e05932d1b6acfd (patch)
tree4db5d307a3ed93eb7c1fa1ec3a75b25243ce6913 /libc/stdlib/malloc-simple
parente5104517c1812dbee65e0994650e92e8d99dc9c0 (diff)
Update and restore malloc-simple. Slow as molasses, but trivially
simple and releases memory immediately when asked to do so. -Erik
Diffstat (limited to 'libc/stdlib/malloc-simple')
-rw-r--r--libc/stdlib/malloc-simple/Makefile44
-rw-r--r--libc/stdlib/malloc-simple/alloc.c189
2 files changed, 233 insertions, 0 deletions
diff --git a/libc/stdlib/malloc-simple/Makefile b/libc/stdlib/malloc-simple/Makefile
new file mode 100644
index 000000000..1da7a672c
--- /dev/null
+++ b/libc/stdlib/malloc-simple/Makefile
@@ -0,0 +1,44 @@
+# Makefile for uClibc
+#
+# Copyright (C) 2000-2003 Erik Andersen <andersen@uclibc.org>
+#
+# This program is free software; you can redistribute it and/or modify it under
+# the terms of the GNU Library General Public License as published by the Free
+# Software Foundation; either version 2 of the License, or (at your option) any
+# later version.
+#
+# This program is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+# FOR A PARTICULAR PURPOSE. See the GNU Library General Public License for more
+# details.
+#
+# You should have received a copy of the GNU Library General Public License
+# along with this program; if not, write to the Free Software Foundation, Inc.,
+# 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+#
+# Derived in part from the Linux-8086 C library, the GNU C Library, and several
+# other sundry sources. Files within this library are copyright by their
+# respective copyright holders.
+
+TOPDIR=../../../
+include $(TOPDIR)Rules.mak
+
+MSRC=alloc.c
+MOBJ=malloc.o realloc.o free.o calloc.o memalign.o
+OBJS=$(MOBJ)
+
+
+all: $(OBJS) $(LIBC)
+
+$(LIBC): ar-target
+
+ar-target: $(OBJS)
+ $(AR) $(ARFLAGS) $(LIBC) $(OBJS)
+
+$(MOBJ): $(MSRC)
+ $(CC) $(CFLAGS) -DL_$* $< -c -o $*.o
+ $(STRIPTOOL) -x -R .note -R .comment $*.o
+
+clean:
+ rm -f *.[oa] *~ core
+
diff --git a/libc/stdlib/malloc-simple/alloc.c b/libc/stdlib/malloc-simple/alloc.c
new file mode 100644
index 000000000..ee0135581
--- /dev/null
+++ b/libc/stdlib/malloc-simple/alloc.c
@@ -0,0 +1,189 @@
+/* alloc.c
+ *
+ * Written by Erik Andersen <andersee@debian.org>
+ * LGPLv2
+ *
+ * Parts of the memalign code were stolen from malloc-930716.
+ */
+
+#include <features.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/mman.h>
+
+
+#ifdef L_malloc
+void *malloc(size_t size)
+{
+ void *result;
+
+ if (unlikely(size == 0)) {
+#if defined(__MALLOC_GLIBC_COMPAT__)
+ size++;
+#else
+ /* Some programs will call malloc (0). Lets be strict and return NULL */
+ return 0;
+#endif
+ }
+
+#ifdef __UCLIBC_HAS_MMU__
+ result = mmap((void *) 0, size + sizeof(size_t), PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, 0, 0);
+ if (result == MAP_FAILED)
+ return 0;
+ * (size_t *) result = size;
+ return(result + sizeof(size_t));
+#else
+ result = mmap((void *) 0, size, PROT_READ | PROT_WRITE,
+ MAP_SHARED | MAP_ANONYMOUS, 0, 0);
+ if (result == MAP_FAILED)
+ return 0;
+ return(result);
+#endif
+}
+#endif
+
+#ifdef L_calloc
+void *calloc(size_t num, size_t size)
+{
+ void *ptr = malloc(num * size);
+ if (ptr)
+ memset(ptr, 0, num * size);
+ return ptr;
+}
+#endif
+
+#ifdef L_realloc
+void *realloc(void *ptr, size_t size)
+{
+ void *newptr = NULL;
+
+ if (!ptr)
+ return malloc(size);
+ if (!size) {
+ free(ptr);
+ return malloc(0);
+ }
+
+ newptr = malloc(size);
+ if (newptr) {
+ memcpy(newptr, ptr,
+#ifdef __UCLIBC_HAS_MMU__
+ *((size_t *) (ptr - sizeof(size_t)))
+#else
+ size
+#endif
+ );
+ free(ptr);
+ }
+ return newptr;
+}
+#endif
+
+#ifdef L_free
+extern int weak_function __libc_free_aligned(void *ptr);
+void free(void *ptr)
+{
+ if (ptr == NULL)
+ return;
+ if (unlikely(__libc_free_aligned!=NULL)) {
+ if (__libc_free_aligned(ptr)) {
+ return;
+ }
+ }
+#ifdef __UCLIBC_HAS_MMU__
+ ptr -= sizeof(size_t);
+ munmap(ptr, * (size_t *) ptr + sizeof(size_t));
+#else
+ munmap(ptr, 0);
+#endif
+}
+#endif
+
+#ifdef L_memalign
+#ifdef __UCLIBC_HAS_THREADS__
+#include <pthread.h>
+extern pthread_mutex_t __malloclock;
+# define LOCK __pthread_mutex_lock(&__malloclock)
+# define UNLOCK __pthread_mutex_unlock(&__malloclock);
+#else
+# define LOCK
+# define UNLOCK
+#endif
+
+/* List of blocks allocated with memalign or valloc */
+struct alignlist
+{
+ struct alignlist *next;
+ __ptr_t aligned; /* The address that memaligned returned. */
+ __ptr_t exact; /* The address that malloc returned. */
+};
+struct alignlist *_aligned_blocks;
+
+/* Return memory to the heap. */
+int __libc_free_aligned(void *ptr)
+{
+ struct alignlist *l;
+
+ if (ptr == NULL)
+ return 0;
+
+ LOCK;
+ for (l = _aligned_blocks; l != NULL; l = l->next) {
+ if (l->aligned == ptr) {
+ /* Mark the block as free */
+ l->aligned = NULL;
+ ptr = l->exact;
+#ifdef __UCLIBC_HAS_MMU__
+ ptr -= sizeof(size_t);
+ munmap(ptr, * (size_t *) ptr + sizeof(size_t));
+#else
+ munmap(ptr, 0);
+#endif
+ return 1;
+ }
+ }
+ UNLOCK;
+ return 0;
+}
+void * memalign (size_t alignment, size_t size)
+{
+ void * result;
+ unsigned long int adj;
+
+ result = malloc (size + alignment - 1);
+ if (result == NULL)
+ return NULL;
+ adj = (unsigned long int) ((unsigned long int) ((char *) result -
+ (char *) NULL)) % alignment;
+ if (adj != 0)
+ {
+ struct alignlist *l;
+ LOCK;
+ for (l = _aligned_blocks; l != NULL; l = l->next)
+ if (l->aligned == NULL)
+ /* This slot is free. Use it. */
+ break;
+ if (l == NULL)
+ {
+ l = (struct alignlist *) malloc (sizeof (struct alignlist));
+ if (l == NULL) {
+ free(result);
+ UNLOCK;
+ return NULL;
+ }
+ l->next = _aligned_blocks;
+ _aligned_blocks = l;
+ }
+ l->exact = result;
+ result = l->aligned = (char *) result + alignment - adj;
+ UNLOCK;
+ }
+
+ return result;
+}
+#endif
+