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authorZack Weinberg <zackw@panix.com>2017-02-26 20:17:52 -0500
committerZack Weinberg <zackw@panix.com>2017-03-01 20:33:46 -0500
commit9090848d0607e93fb08a1d68d9f263846ee33f02 (patch)
treed6cd846fff1640a49ef071cfd0bfabb8efa5352c /include/libc-pointer-arith.h
parent5e4e10636cf999c251b623c3be143a22156721d6 (diff)
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Narrowing the visibility of libc-internal.h even further.
posix/wordexp-test.c used libc-internal.h for PTR_ALIGN_DOWN; similar to what was done with libc-diag.h, I have split the definitions of cast_to_integer, ALIGN_UP, ALIGN_DOWN, PTR_ALIGN_UP, and PTR_ALIGN_DOWN to a new header, libc-pointer-arith.h. It then occurred to me that the remaining declarations in libc-internal.h are mostly to do with early initialization, and probably most of the files including it, even in the core code, don't need it anymore. Indeed, only 19 files actually need what remains of libc-internal.h. 23 others need libc-diag.h instead, and 12 need libc-pointer-arith.h instead. No file needs more than one of them, and 16 don't need any of them! So, with this patch, libc-internal.h stops including libc-diag.h as well as losing the pointer arithmetic macros, and all including files are adjusted. * include/libc-pointer-arith.h: New file. Define cast_to_integer, ALIGN_UP, ALIGN_DOWN, PTR_ALIGN_UP, and PTR_ALIGN_DOWN here. * include/libc-internal.h: Definitions of above macros moved from here. Don't include libc-diag.h anymore either. * posix/wordexp-test.c: Include stdint.h and libc-pointer-arith.h. Don't include libc-internal.h. * debug/pcprofile.c, elf/dl-tunables.c, elf/soinit.c, io/openat.c * io/openat64.c, misc/ptrace.c, nptl/pthread_clock_gettime.c * nptl/pthread_clock_settime.c, nptl/pthread_cond_common.c * string/strcoll_l.c, sysdeps/nacl/brk.c * sysdeps/unix/clock_settime.c * sysdeps/unix/sysv/linux/i386/get_clockfreq.c * sysdeps/unix/sysv/linux/ia64/get_clockfreq.c * sysdeps/unix/sysv/linux/powerpc/get_clockfreq.c * sysdeps/unix/sysv/linux/sparc/sparc64/get_clockfreq.c: Don't include libc-internal.h. * elf/get-dynamic-info.h, iconv/loop.c * iconvdata/iso-2022-cn-ext.c, locale/weight.h, locale/weightwc.h * misc/reboot.c, nis/nis_table.c, nptl_db/thread_dbP.h * nscd/connections.c, resolv/res_send.c, soft-fp/fmadf4.c * soft-fp/fmasf4.c, soft-fp/fmatf4.c, stdio-common/vfscanf.c * sysdeps/ieee754/dbl-64/e_lgamma_r.c * sysdeps/ieee754/dbl-64/k_rem_pio2.c * sysdeps/ieee754/flt-32/e_lgammaf_r.c * sysdeps/ieee754/flt-32/k_rem_pio2f.c * sysdeps/ieee754/ldbl-128/k_tanl.c * sysdeps/ieee754/ldbl-128ibm/k_tanl.c * sysdeps/ieee754/ldbl-96/e_lgammal_r.c * sysdeps/ieee754/ldbl-96/k_tanl.c, sysdeps/nptl/futex-internal.h: Include libc-diag.h instead of libc-internal.h. * elf/dl-load.c, elf/dl-reloc.c, locale/programs/locarchive.c * nptl/nptl-init.c, string/strcspn.c, string/strspn.c * malloc/malloc.c, sysdeps/i386/nptl/tls.h * sysdeps/nacl/dl-map-segments.h, sysdeps/x86_64/atomic-machine.h * sysdeps/unix/sysv/linux/spawni.c * sysdeps/x86_64/nptl/tls.h: Include libc-pointer-arith.h instead of libc-internal.h. * elf/get-dynamic-info.h, sysdeps/nacl/dl-map-segments.h * sysdeps/x86_64/atomic-machine.h: Add multiple include guard.
Diffstat (limited to 'include/libc-pointer-arith.h')
-rw-r--r--include/libc-pointer-arith.h60
1 files changed, 60 insertions, 0 deletions
diff --git a/include/libc-pointer-arith.h b/include/libc-pointer-arith.h
new file mode 100644
index 0000000..715cbc1
--- /dev/null
+++ b/include/libc-pointer-arith.h
@@ -0,0 +1,60 @@
+/* Helper macros for pointer arithmetic.
+ Copyright (C) 2012-2017 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#ifndef _LIBC_POINTER_ARITH_H
+#define _LIBC_POINTER_ARITH_H 1
+
+#include <stdint.h>
+
+/* 1 if 'type' is a pointer type, 0 otherwise. */
+# define __pointer_type(type) (__builtin_classify_type ((type) 0) == 5)
+
+/* intptr_t if P is true, or T if P is false. */
+# define __integer_if_pointer_type_sub(T, P) \
+ __typeof__ (*(0 ? (__typeof__ (0 ? (T *) 0 : (void *) (P))) 0 \
+ : (__typeof__ (0 ? (intptr_t *) 0 : (void *) (!(P)))) 0))
+
+/* intptr_t if EXPR has a pointer type, or the type of EXPR otherwise. */
+# define __integer_if_pointer_type(expr) \
+ __integer_if_pointer_type_sub(__typeof__ ((__typeof__ (expr)) 0), \
+ __pointer_type (__typeof__ (expr)))
+
+/* Cast an integer or a pointer VAL to integer with proper type. */
+# define cast_to_integer(val) ((__integer_if_pointer_type (val)) (val))
+
+/* Align a value by rounding down to closest size.
+ e.g. Using size of 4096, we get this behavior:
+ {4095, 4096, 4097} = {0, 4096, 4096}. */
+#define ALIGN_DOWN(base, size) ((base) & -((__typeof__ (base)) (size)))
+
+/* Align a value by rounding up to closest size.
+ e.g. Using size of 4096, we get this behavior:
+ {4095, 4096, 4097} = {4096, 4096, 8192}.
+
+ Note: The size argument has side effects (expanded multiple times). */
+#define ALIGN_UP(base, size) ALIGN_DOWN ((base) + (size) - 1, (size))
+
+/* Same as ALIGN_DOWN(), but automatically casts when base is a pointer. */
+#define PTR_ALIGN_DOWN(base, size) \
+ ((__typeof__ (base)) ALIGN_DOWN ((uintptr_t) (base), (size)))
+
+/* Same as ALIGN_UP(), but automatically casts when base is a pointer. */
+#define PTR_ALIGN_UP(base, size) \
+ ((__typeof__ (base)) ALIGN_UP ((uintptr_t) (base), (size)))
+
+#endif