allocating any. It is a good idea to use alloca(0) in
your main control loop, etc. to force garbage collection. */
+/*
+
+@deftypefn Replacement void* alloca (size_t @var{size})
+
+This function allocates memory which will be automatically reclaimed
+after the procedure exits. The @libib{} implementation does not free
+the memory immediately but will do so eventually during subsequent
+calls to this function. Memory is allocated using @code{xmalloc} under
+normal circumstances.
+
+The header file @file{alloca-conf.h} can be used in conjunction with the
+GNU Autoconf test @code{AC_FUNC_ALLOCA} to test for and properly make
+available this function. The @code{AC_FUNC_ALLOCA} test requires that
+client code use a block of preprocessor code to be safe (see the Autoconf
+manual for more); this header incorporates that logic and more, including
+the possibility of a GCC built-in function.
+
+@end deftypefn
+
+*/
+
#ifdef HAVE_CONFIG_H
-#include "config.h"
+#include <config.h>
#endif
-/* If compiling with GCC, this file's not needed. */
-#ifndef alloca
+#include <libiberty.h>
-#ifdef emacs
-#ifdef static
-/* actually, only want this if static is defined as ""
- -- this is for usg, in which emacs must undefine static
- in order to make unexec workable
- */
-#ifndef STACK_DIRECTION
-you
-lose
--- must know STACK_DIRECTION at compile-time
-#endif /* STACK_DIRECTION undefined */
-#endif /* static */
-#endif /* emacs */
+#ifdef HAVE_STRING_H
+#include <string.h>
+#endif
+#ifdef HAVE_STDLIB_H
+#include <stdlib.h>
+#endif
+
+/* These variables are used by the ASTRDUP implementation that relies
+ on C_alloca. */
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+const char *libiberty_optr;
+char *libiberty_nptr;
+unsigned long libiberty_len;
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
/* If your stack is a linked list of frames, you have to
provide an "address metric" ADDRESS_FUNCTION macro. */
#if defined (CRAY) && defined (CRAY_STACKSEG_END)
-long i00afunc ();
+static long i00afunc ();
#define ADDRESS_FUNCTION(arg) (char *) i00afunc (&(arg))
#else
#define ADDRESS_FUNCTION(arg) &(arg)
#endif
-#if __STDC__
-#include <stddef.h>
-typedef void *pointer;
-#else
-typedef char *pointer;
-typedef unsigned size_t;
-#endif
-
#ifndef NULL
#define NULL 0
#endif
-/* Different portions of Emacs need to call different versions of
- malloc. The Emacs executable needs alloca to call xmalloc, because
- ordinary malloc isn't protected from input signals. On the other
- hand, the utilities in lib-src need alloca to call malloc; some of
- them are very simple, and don't have an xmalloc routine.
-
- Non-Emacs programs expect this to call use xmalloc.
-
- Callers below should use malloc. */
-
-#ifndef emacs
-#define malloc xmalloc
-extern pointer xmalloc ();
-#endif
-
/* Define STACK_DIRECTION if you know the direction of stack
growth for your system; otherwise it will be automatically
deduced at run-time.
#define STACK_DIR stack_dir
static void
-find_stack_direction ()
+find_stack_direction (void)
{
static char *addr = NULL; /* Address of first `dummy', once known. */
auto char dummy; /* To get stack address. */
caller, but that method cannot be made to work for some
implementations of C, for example under Gould's UTX/32. */
-pointer
-alloca (size)
- size_t size;
+/* @undocumented C_alloca */
+
+PTR
+C_alloca (size_t size)
{
auto char probe; /* Probes stack depth: */
register char *depth = ADDRESS_FUNCTION (probe);
#endif
/* Reclaim garbage, defined as all alloca'd storage that
- was allocated from deeper in the stack than currently. */
+ was allocated from deeper in the stack than currently. */
{
register header *hp; /* Traverses linked list. */
{
register header *np = hp->h.next;
- free ((pointer) hp); /* Collect garbage. */
+ free ((PTR) hp); /* Collect garbage. */
hp = np; /* -> next header. */
}
/* Allocate combined header + user data storage. */
{
- register pointer new = malloc (sizeof (header) + size);
+ register void *new_storage = XNEWVEC (char, sizeof (header) + size);
/* Address of header. */
- ((header *) new)->h.next = last_alloca_header;
- ((header *) new)->h.deep = depth;
+ if (new_storage == 0)
+ abort();
- last_alloca_header = (header *) new;
+ ((header *) new_storage)->h.next = last_alloca_header;
+ ((header *) new_storage)->h.deep = depth;
+
+ last_alloca_header = (header *) new_storage;
/* User storage begins just after header. */
- return (pointer) ((char *) new + sizeof (header));
+ return (PTR) ((char *) new_storage + sizeof (header));
}
}
#ifdef CRAY2
/* Determine a "stack measure" for an arbitrary ADDRESS.
- I doubt that "lint" will like this much. */
+ I doubt that "lint" will like this much. */
static long
i00afunc (long *address)
#endif /* not CRAY2 */
#endif /* CRAY */
-
-#endif /* no alloca */
OSDN Git Service
