From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from localhost (localhost [127.0.0.1]) by olra.theworths.org (Postfix) with ESMTP id 27627431FBF for ; Tue, 26 Nov 2013 05:08:04 -0800 (PST) X-Virus-Scanned: Debian amavisd-new at olra.theworths.org X-Spam-Flag: NO X-Spam-Score: 0 X-Spam-Level: X-Spam-Status: No, score=0 tagged_above=-999 required=5 tests=[none] autolearn=disabled Received: from olra.theworths.org ([127.0.0.1]) by localhost (olra.theworths.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id KfU3jAf6E6Ep for ; Tue, 26 Nov 2013 05:07:56 -0800 (PST) Received: from yantan.tethera.net (yantan.tethera.net [199.188.72.155]) (using TLSv1 with cipher DHE-RSA-AES128-SHA (128/128 bits)) (No client certificate requested) by olra.theworths.org (Postfix) with ESMTPS id 33642431FB6 for ; Tue, 26 Nov 2013 05:07:56 -0800 (PST) Received: from remotemail by yantan.tethera.net with local (Exim 4.80) (envelope-from ) id 1VlIMq-0008Tq-Kw; Tue, 26 Nov 2013 09:07:52 -0400 Received: (nullmailer pid 31884 invoked by uid 1000); Tue, 26 Nov 2013 13:07:48 -0000 From: david@tethera.net To: notmuch@notmuchmail.org Subject: [PATCH] util: detect byte order Date: Tue, 26 Nov 2013 09:07:37 -0400 Message-Id: <1385471257-31835-1-git-send-email-david@tethera.net> X-Mailer: git-send-email 1.8.4.2 In-Reply-To: <1385328583-24602-2-git-send-email-david@tethera.net> References: <1385328583-24602-2-git-send-email-david@tethera.net> X-BeenThere: notmuch@notmuchmail.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: "Use and development of the notmuch mail system." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 26 Nov 2013 13:08:04 -0000 From: David Bremner Unfortunately old versions of GCC and clang do not provide byte order macros, so we re-invent them. If UTIL_BYTE_ORDER is not defined, we fall back to macros supported by recent versions of GCC and clang --- I pushed the series id:1385328583-24602-1-git-send-email-david@tethera.net; unfortunately that broke compilation on old versions of GCC, in particular on our buildbot. Here is a proposed fix for the fix. configure | 26 ++++++++++++++++++++++++-- lib/libsha1.c | 19 +++++-------------- util/endian-util.h | 39 +++++++++++++++++++++++++++++++++++++++ 3 files changed, 68 insertions(+), 16 deletions(-) create mode 100644 util/endian-util.h diff --git a/configure b/configure index 1a8e939..02d6396 100755 --- a/configure +++ b/configure @@ -441,6 +441,21 @@ else EOF fi +printf "Checking byte order... " +cat> _byteorder.c < +#include +#include +uint32_t test = 0x31323334; +char buf[5]; +int main() { memcpy(buf, &test, 4); buf[4] = '\0'; printf("%s\n", buf); return 0; } +EOF +${CC} ${CFLAGS} _byteorder.c -o _byteorder > /dev/null 2>&1 +util_byte_order=$(./_byteorder) +echo $util_byte_order + +#rm -f _byteorder _byteorder.c + if [ $errors -gt 0 ]; then cat < /* for memcpy() etc. */ - +#include "endian-util.h" #include "libsha1.h" #if defined(__cplusplus) @@ -49,20 +49,11 @@ extern "C" #define bswap_32(x) ((rotr32((x), 24) & 0x00ff00ff) | (rotr32((x), 8) & 0xff00ff00)) -/* The macros __BYTE_ORDER__ and __ORDER_*_ENDIAN__ are GNU C - * extensions. They are also supported by clang as of v3.2 */ - -#ifdef __BYTE_ORDER__ -# if (__BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__) -# define bsw_32(p,n) \ - { int _i = (n); while(_i--) ((uint32_t*)p)[_i] = bswap_32(((uint32_t*)p)[_i]); } -# elif (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__) -# define bsw_32(p,n) -# else -# error "unknown byte order" -# endif +#if (UTIL_BYTE_ORDER == UTIL_ORDER_LITTLE_ENDIAN) +# define bsw_32(p,n) \ + { int _i = (n); while(_i--) ((uint32_t*)p)[_i] = bswap_32(((uint32_t*)p)[_i]); } #else -# error "macro __BYTE_ORDER__ is not defined" +# define bsw_32(p,n) #endif #define SHA1_MASK (SHA1_BLOCK_SIZE - 1) diff --git a/util/endian-util.h b/util/endian-util.h new file mode 100644 index 0000000..cbecf66 --- /dev/null +++ b/util/endian-util.h @@ -0,0 +1,39 @@ +/* this file mimics the macros present in recent GCC and CLANG */ + +#ifndef _ENDIAN_UTIL_H +#define _ENDIAN_UTIL_H + +/* This are prefixed with UTIL to avoid collisions + * + * You can use something like the following to define UTIL_BYTE_ORDER + * in a configure script. + */ +#if 0 +#include +#include +#include +uint32_t test = 0x31323334; +char buf[5]; +int main() { memcpy(buf, &test, 4); buf[4] = '\0'; printf("%s\n", buf); return 0; } +#endif + +#define UTIL_ORDER_LITTLE_ENDIAN 4321 +#define UTIL_ORDER_BIG_ENDIAN 1234 + + +#if !defined(UTIL_BYTE_ORDER) || ((UTIL_BYTE_ORDER != UTIL_ORDER_LITTLE_ENDIAN) && \ + (UTIL_BYTE_ORDER != UTIL_ORDER_LITTLE_ENDIAN)) +#ifdef __BYTE_ORDER__ +# if (__BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__) +# define UTIL_BYTE_ORDER UTIL_ORDER_LITTLE_ENDIAN +# elif (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__) +# define UTIL_BYTE_ORDER UTIL_ORDER_BIG_ENDIAN +# else +# error "Unsupported __BYTE_ORDER__" +# endif +#else +# error "UTIL_BYTE_ORDER not correctly defined and __BYTE_ORDER__ not defined." +#endif +#endif + +#endif -- 1.8.4.2