+2005-03-03 Derek R. Price <derek@ximbiot.com>
+ Bruno Haible <bruno@clisp.org>
+
+ * modules/pagealign_alloc: New file.
+ * MODULES.html.sh (Memory management functions): Add pagealign_alloc.
+
2005-03-01 Paul Eggert <eggert@cs.ucla.edu>
* modules/gettime (Makefile.am): Remove lib_SOURCES line.
+2005-03-03 Derek R. Price <derek@ximbiot.com>
+ Bruno Haible <bruno@clisp.org>
+
+ * pagealign_alloc.h: New file.
+ * pagealign_alloc.c: New file.
+
2005-01-28 Bruno Haible <bruno@clisp.org>
* stpncpy.h (stpncpy): Define as a macro without arguments, so that
--- /dev/null
+/* Memory allocation aligned to system page boundaries.
+
+ Copyright (C) 2005 Free Software Foundation, Inc.
+
+ This program is free software; you can redistribute it and/or modify it
+ under the terms of the GNU General Public License as published
+ by the Free Software Foundation; either version 2, 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
+ General Public License for more details.
+
+ You should have received a copy of the GNU 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. */
+
+/* Written by Derek R. Price <derek@ximbiot.com>. */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include "pagealign_alloc.h"
+
+#include <errno.h>
+#include <stdlib.h>
+
+#if HAVE_FCNTL_H
+# include <fcntl.h>
+#endif
+
+#if HAVE_UNISTD_H
+# include <unistd.h>
+#endif
+
+#if HAVE_MMAP
+# include <sys/mman.h>
+#endif
+
+#include "error.h"
+#include "exit.h"
+#include "getpagesize.h"
+#include "xalloc.h"
+
+
+#if HAVE_MMAP || ! HAVE_POSIX_MEMALIGN
+
+# if HAVE_MMAP
+/* For each memory region, we store its size. */
+typedef size_t info_t;
+# else
+/* For each memory region, we store the original pointer returned by
+ malloc(). */
+typedef void * info_t;
+# endif
+
+/* A simple linked list of allocated memory regions. It is probably not the
+ most efficient way to store these, but anyway... */
+typedef struct memnode_s memnode_t;
+struct memnode_s
+{
+ void *aligned_ptr;
+ info_t info;
+ memnode_t *next;
+};
+
+/* The list of currently allocated memory regions. */
+static memnode_t *memnode_table = NULL;
+
+
+static void
+new_memnode (void *aligned_ptr, info_t info)
+{
+ memnode_t *new_node = (memnode_t *) xmalloc (sizeof (memnode_t));
+ new_node->aligned_ptr = aligned_ptr;
+ new_node->info = info;
+ new_node->next = memnode_table;
+ memnode_table = new_node;
+}
+
+
+/* Dispose of the memnode containing a map for the ALIGNED_PTR in question
+ and return the content of the node's INFO field. */
+static info_t
+get_memnode (void *aligned_ptr)
+{
+ info_t ret;
+ memnode_t *c;
+ memnode_t **p_next = &memnode_table;
+
+ for (c = *p_next; c != NULL; p_next = &c->next, c = c->next)
+ if (c->aligned_ptr == aligned_ptr)
+ break;
+
+ if (!c)
+ /* An attempt to free untracked memory. A wrong pointer was passed
+ to pagealign_free(). */
+ abort ();
+
+ /* Remove this entry from the list, save the return value, and free it. */
+ *p_next = c->next;
+ ret = c->info;
+ free (c);
+
+ return ret;
+}
+
+#endif /* HAVE_MMAP || !HAVE_POSIX_MEMALIGN */
+
+
+void *
+pagealign_alloc (size_t size)
+{
+ void *ret;
+#if HAVE_MMAP
+ int flags;
+ static int fd = -1; /* Only open /dev/zero once in order to avoid limiting
+ the amount of memory we may allocate based on the
+ number of open file descriptors. */
+# ifdef HAVE_MAP_ANONYMOUS
+ flags = MAP_ANONYMOUS | MAP_PRIVATE;
+ fd = -1;
+# else /* !HAVE_MAP_ANONYMOUS */
+ flags = MAP_FILE | MAP_PRIVATE;
+ if (fd == -1)
+ {
+ fd = open ("/dev/zero", O_RDONLY, 0666);
+ if (fd < 0)
+ error (EXIT_FAILURE, errno, "Failed to open /dev/zero for read");
+ }
+# endif /* HAVE_MAP_ANONYMOUS */
+ ret = mmap (NULL, size, PROT_READ | PROT_WRITE, flags, fd, 0);
+ if (!ret)
+ error (EXIT_FAILURE, errno, "mmap to /dev/zero failed");
+ new_memnode (ret, size);
+#elif HAVE_POSIX_MEMALIGN
+ int status = posix_memalign (&ret, getpagesize (), size);
+ if (status)
+ error (EXIT_FAILURE, status, "posix_memalign failed");
+#else /* !HAVE_MMAP && !HAVE_POSIX_MEMALIGN */
+ size_t pagesize = getpagesize ();
+ void *unaligned_ptr = xmalloc (size + pagesize - 1);
+ ret = (char *) unaligned_ptr
+ + ((- (unsigned long) unaligned_ptr) & (pagesize - 1));
+ new_memnode (ret, unaligned_ptr);
+#endif /* HAVE_MMAP && HAVE_POSIX_MEMALIGN */
+ return ret;
+}
+
+
+void
+pagealign_free (void *aligned_ptr)
+{
+#if HAVE_MMAP
+ munmap (aligned_ptr, get_memnode (aligned_ptr));
+#elif HAVE_POSIX_MEMALIGN
+ free (aligned_ptr);
+#else
+ free (get_memnode (aligned_ptr));
+#endif
+}
--- /dev/null
+/* Memory allocation aligned to system page boundaries.
+
+ Copyright (C) 2005 Free Software Foundation, Inc.
+
+ This program is free software; you can redistribute it and/or modify it
+ under the terms of the GNU General Public License as published
+ by the Free Software Foundation; either version 2, 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
+ General Public License for more details.
+
+ You should have received a copy of the GNU 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. */
+
+#ifndef _PAGEALIGN_ALLOC_H
+# define _PAGEALIGN_ALLOC_H
+
+# include <stddef.h>
+
+/* Allocate a block of memory of SIZE bytes, aligned on a system page
+ boundary.
+ If SIZE is not a multiple of the system page size, it will be rounded up
+ to the next multiple.
+ Return a pointer to the start of the memory block, or NULL if the allocation
+ failed. */
+extern void *pagealign_alloc (size_t size);
+
+/* Free a memory block.
+ PTR must be a pointer returned by pagealign_alloc. */
+extern void pagealign_free (void *ptr);
+
+#endif /* _PAGEALIGN_ALLOC_H */
+2005-03-03 Derek R. Price <derek@ximbiot.com>
+
+ * mmap-anon.m4: New file.
+ * pagealign_alloc.m4: New file.
+
2005-01-28 Bruno Haible <bruno@clisp.org>
* stpncpy.m4 (gl_FUNC_STPNCPY): Undo the replacement here. Because of
--- /dev/null
+# mmap-anon.m4 serial 1
+dnl Copyright (C) 2005 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+AC_DEFUN([gl_FUNC_MMAP],
+[
+ dnl Work around a bug of AC_EGREP_CPP in autoconf-2.57.
+ AC_REQUIRE([AC_PROG_CPP])
+ AC_REQUIRE([AC_PROG_EGREP])
+
+ dnl Persuade glibc <sys/mman.h> to define MAP_ANONYMOUS.
+ AC_REQUIRE([AC_GNU_SOURCE])
+
+ # Check for mmap()
+ AC_FUNC_MMAP
+
+ # Try to allow MAP_ANONYMOUS.
+ gl_have_mmap_anonymous=no
+ if test $ac_cv_func_mmap_fixed_mapped = yes; then
+ AC_MSG_CHECKING([for MAP_ANONYMOUS])
+ AC_EGREP_CPP([I cant identify this map.], [
+#include <sys/mman.h>
+#ifdef MAP_ANONYMOUS
+ I cant identify this map.
+#endif
+],
+ [gl_have_mmap_anonymous=yes])
+ if test $gl_have_mmap_anonymous = no; then
+ AC_EGREP_HEADER([MAP_ANON], [
+#include <sys/mman.h>
+#ifdef MAP_ANON
+ I cant identify this map.
+#endif
+],
+ [AC_DEFINE(MAP_ANONYMOUS, MAP_ANON,
+ [Define to a substitute value for mmap()'s MAP_ANONYMOUS flag.])
+ gl_have_mmap_anonymous=yes])
+ fi
+ AC_MSG_RESULT($gl_have_mmap_anonymous)
+ if test $gl_have_mmap_anonymous = yes; then
+ AC_DEFINE(HAVE_MAP_ANONYMOUS, 1,
+ [Define to 1 if mmap()'s MAP_ANONYMOUS flag is available after including
+ config.h and <sys/mman.h>.])
+ fi
+
+ AH_VERBATIM([MAP_FILE],
+[/* Define MAP_FILE when it isn't otherwise. */
+#ifndef MAP_FILE
+# define MAP_FILE 0
+#endif])
+ fi
+])
--- /dev/null
+# pagealign_alloc.m4 serial 1
+dnl Copyright (C) 2005 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+AC_DEFUN([gl_PAGEALIGN_ALLOC],
+[
+ dnl Persuade glibc <sys/mman.h> to define MAP_ANONYMOUS.
+ AC_REQUIRE([AC_GNU_SOURCE])
+
+ AC_LIBSOURCE([pagealign_alloc.h])
+ AC_LIBOBJ([pagealign_alloc])
+ gl_PREREQ_PAGEALIGN_ALLOC
+])
+
+# Prerequisites of lib/pagealign_alloc.c.
+AC_DEFUN([gl_PREREQ_PAGEALIGN_ALLOC],
+[
+ AC_REQUIRE([gl_FUNC_MMAP])
+ AC_REQUIRE([gl_GETPAGESIZE])
+ AC_CHECK_FUNCS_ONCE([posix_memalign])
+ AC_CHECK_HEADERS_ONCE([fcntl.h unistd.h])
+])
--- /dev/null
+Description:
+Memory allocation aligned on page boundaries.
+
+Files:
+lib/pagealign_alloc.h
+lib/pagealign_alloc.c
+m4/mmap-anon.m4
+m4/pagealign_alloc.m4
+
+Depends-on:
+error
+exit
+getpagesize
+xalloc
+
+configure.ac:
+gl_PAGEALIGN_ALLOC
+
+Makefile.am:
+
+Include:
+#include "pagealign_alloc.h"
+
+License:
+GPL
+
+Maintainer:
+bug-gnulib@gnu.org
projects / gnulib.git / commitdiff