import newlib-2000-02-17 snapshot

1 files changed, 206 insertions, 0 deletions

diff --git a/newlib/libc/stdlib/malloc.c b/newlib/libc/stdlib/malloc.c
new file mode 100644
index 0000000..83453ab
--- /dev/null
+++ b/newlib/libc/stdlib/malloc.c
@@ -0,0 +1,206 @@
+/* VxWorks provides its own version of malloc, and we can't use this
+   one because VxWorks does not provide sbrk.  So we have a hook to
+   not compile this code.  */
+
+/* The routines here are simple cover fns to the routines that do the real
+   work (the reentrant versions).  */
+/* FIXME: Does the warning below (see WARNINGS) about non-reentrancy still
+   apply?  A first guess would be "no", but how about reentrancy in the *same*
+   thread?  */
+
+#ifdef MALLOC_PROVIDED
+
+int _dummy_malloc = 1;
+
+#else
+
+/*
+FUNCTION
+<<malloc>>, <<realloc>>, <<free>>---manage memory
+
+INDEX
+	malloc
+INDEX
+	realloc
+INDEX
+	free
+INDEX
+	memalign
+INDEX
+	malloc_usable_size
+INDEX
+	_malloc_r
+INDEX
+	_realloc_r
+INDEX
+	_free_r
+INDEX
+	_memalign_r
+INDEX
+	_malloc_usable_size_r
+
+ANSI_SYNOPSIS
+	#include <stdlib.h>
+	void *malloc(size_t <[nbytes]>);
+	void *realloc(void *<[aptr]>, size_t <[nbytes]>);
+	void free(void *<[aptr]>);
+
+	void *memalign(size_t <[align]>, size_t <[nbytes]>);
+
+	size_t malloc_usable_size(void *<[aptr]>);
+
+	void *_malloc_r(void *<[reent]>, size_t <[nbytes]>);
+	void *_realloc_r(void *<[reent]>, 
+                         void *<[aptr]>, size_t <[nbytes]>);
+	void _free_r(void *<[reent]>, void *<[aptr]>);
+
+	void *_memalign_r(void *<[reent]>,
+			  size_t <[align]>, size_t <[nbytes]>);
+
+	size_t _malloc_usable_size_r(void *<[reent]>, void *<[aptr]>);
+
+TRAD_SYNOPSIS
+	#include <stdlib.h>
+	char *malloc(<[nbytes]>)
+	size_t <[nbytes]>;
+
+	char *realloc(<[aptr]>, <[nbytes]>)
+	char *<[aptr]>;
+	size_t <[nbytes]>;
+
+	void free(<[aptr]>)
+	char *<[aptr]>;
+
+	char *memalign(<[align]>, <[nbytes]>)
+	size_t <[align]>;
+	size_t <[nbytes]>;
+
+	size_t malloc_usable_size(<[aptr]>)
+	char *<[aptr]>;
+
+	char *_malloc_r(<[reent]>,<[nbytes]>)
+	char *<[reent]>;
+	size_t <[nbytes]>;
+
+	char *_realloc_r(<[reent]>, <[aptr]>, <[nbytes]>)
+	char *<[reent]>;
+	char *<[aptr]>;
+	size_t <[nbytes]>;
+
+	void _free_r(<[reent]>, <[aptr]>)
+	char *<[reent]>;
+	char *<[aptr]>;
+
+	char *_memalign_r(<[reent]>, <[align]>, <[nbytes]>)
+	char *<[reent]>;
+	size_t <[align]>;
+	size_t <[nbytes]>;
+
+	size_t malloc_usable_size(<[reent]>, <[aptr]>)
+	char *<[reent]>;
+	char *<[aptr]>;
+
+DESCRIPTION
+These functions manage a pool of system memory.
+
+Use <<malloc>> to request allocation of an object with at least
+<[nbytes]> bytes of storage available.  If the space is available,
+<<malloc>> returns a pointer to a newly allocated block as its result.
+
+If you already have a block of storage allocated by <<malloc>>, but
+you no longer need all the space allocated to it, you can make it
+smaller by calling <<realloc>> with both the object pointer and the
+new desired size as arguments.  <<realloc>> guarantees that the
+contents of the smaller object match the beginning of the original object.
+
+Similarly, if you need more space for an object, use <<realloc>> to
+request the larger size; again, <<realloc>> guarantees that the
+beginning of the new, larger object matches the contents of the
+original object.
+
+When you no longer need an object originally allocated by <<malloc>>
+or <<realloc>> (or the related function <<calloc>>), return it to the
+memory storage pool by calling <<free>> with the address of the object
+as the argument.  You can also use <<realloc>> for this purpose by
+calling it with <<0>> as the <[nbytes]> argument.
+
+The <<memalign>> function returns a block of size <[nbytes]> aligned
+to a <[align]> boundary.  The <[align]> argument must be a power of
+two.
+
+The <<malloc_usable_size>> function takes a pointer to a block
+allocated by <<malloc>>.  It returns the amount of space that is
+available in the block.  This may or may not be more than the size
+requested from <<malloc>>, due to alignment or minimum size
+constraints.
+
+The alternate functions <<_malloc_r>>, <<_realloc_r>>, <<_free_r>>,
+<<_memalign_r>>, and <<_malloc_usable_size_r>> are reentrant versions.
+The extra argument <[reent]> is a pointer to a reentrancy structure.
+
+If you have multiple threads of execution which may call any of these
+routines, or if any of these routines may be called reentrantly, then
+you must provide implementations of the <<__malloc_lock>> and
+<<__malloc_unlock>> functions for your system.  See the documentation
+for those functions.
+
+These functions operate by calling the function <<_sbrk_r>> or
+<<sbrk>>, which allocates space.  You may need to provide one of these
+functions for your system.  <<_sbrk_r>> is called with a positive
+value to allocate more space, and with a negative value to release
+previously allocated space if it is no longer required.
+@xref{Stubs}.
+
+RETURNS
+<<malloc>> returns a pointer to the newly allocated space, if
+successful; otherwise it returns <<NULL>>.  If your application needs
+to generate empty objects, you may use <<malloc(0)>> for this purpose.
+
+<<realloc>> returns a pointer to the new block of memory, or <<NULL>>
+if a new block could not be allocated.  <<NULL>> is also the result
+when you use `<<realloc(<[aptr]>,0)>>' (which has the same effect as
+`<<free(<[aptr]>)>>').  You should always check the result of
+<<realloc>>; successful reallocation is not guaranteed even when
+you request a smaller object.
+
+<<free>> does not return a result.
+
+<<memalign>> returns a pointer to the newly allocated space.
+
+<<malloc_usable_size>> returns the usable size.
+
+PORTABILITY
+<<malloc>>, <<realloc>>, and <<free>> are specified by the ANSI C
+standard, but other conforming implementations of <<malloc>> may
+behave differently when <[nbytes]> is zero.
+
+<<memalign>> is part of SVR4.
+
+<<malloc_usable_size>> is not portable.
+
+Supporting OS subroutines required: <<sbrk>>.  */
+
+#include <_ansi.h>
+#include <reent.h>
+#include <stdlib.h>
+#include <malloc.h>
+
+#ifndef _REENT_ONLY
+
+_PTR
+_DEFUN (malloc, (nbytes),
+	size_t nbytes)		/* get a block */
+{
+  return _malloc_r (_REENT, nbytes);
+}
+
+void
+_DEFUN (free, (aptr),
+	_PTR aptr)
+{
+  _free_r (_REENT, aptr);
+}
+
+#endif
+
+#endif /* ! defined (MALLOC_PROVIDED) */