From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yiannis Marangos Subject: [PATCH v7 1/2] Add xpread() and xpwrite() Date: Thu, 10 Apr 2014 21:31:20 +0300 Message-ID: <1397154681-31803-1-git-send-email-yiannis.marangos@gmail.com> References: <1397081197-14803-1-git-send-email-yiannis.marangos@gmail.com> Cc: Yiannis Marangos To: git@vger.kernel.org X-From: git-owner@vger.kernel.org Thu Apr 10 20:31:51 2014 Return-path: Envelope-to: gcvg-git-2@plane.gmane.org Received: from vger.kernel.org ([209.132.180.67]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1WYJlM-00028Y-BK for gcvg-git-2@plane.gmane.org; Thu, 10 Apr 2014 20:31:48 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758893AbaDJSbl (ORCPT ); Thu, 10 Apr 2014 14:31:41 -0400 Received: from mail-ee0-f51.google.com ([74.125.83.51]:54840 "EHLO mail-ee0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753011AbaDJSbj (ORCPT ); Thu, 10 Apr 2014 14:31:39 -0400 Received: by mail-ee0-f51.google.com with SMTP id c13so3304739eek.24 for ; Thu, 10 Apr 2014 11:31:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=2tVbReh9F4Ql6im43xaD72RLubbF3enkydEWK044Qc8=; b=J+rVyyOW4EODb9CLcRy/+o8hfK8JPxXrta6oK9Gamkhvz7lqRVb1HPLt+J4iaDvSvf eDJJISjNKCPiJpsga7XgvXgHcjrPCYaCSJWMPfybU+xBCYsGm0LVmoqH8zz7x5ZGvf+9 qaft87eKSvN7LYRVrEmGj73v9g6SZw6W2uortTVLBWQHHdjBUnvGs3/rRW1oSnyqdC8O 6mWWbAmWNgTBxI8viVk3/tXaSOMC+kL2MuyRdIeGrGgkxmBxQIOmVJLQPyGjm/UY+QKE oV9uK2zpizYP5vLLEv8/3r2OBRVAIxRg6ZyfAxIf4vg/uXGeCnwaT1B4NeJEdNonKJbs OdeQ== X-Received: by 10.14.214.198 with SMTP id c46mr22912481eep.29.1397154698261; Thu, 10 Apr 2014 11:31:38 -0700 (PDT) Received: from abyss.hitronhub.home ([46.251.117.183]) by mx.google.com with ESMTPSA id l42sm11739629eew.19.2014.04.10.11.31.36 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Thu, 10 Apr 2014 11:31:37 -0700 (PDT) X-Mailer: git-send-email 1.9.1 In-Reply-To: <1397081197-14803-1-git-send-email-yiannis.marangos@gmail.com> Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: xpread() and xpwrite() pay attention to EAGAIN/EINTR, so they will resume automatically on interrupted call. Signed-off-by: Yiannis Marangos --- builtin/index-pack.c | 2 +- compat/mmap.c | 4 +--- git-compat-util.h | 2 ++ wrapper.c | 36 ++++++++++++++++++++++++++++++++++++ 4 files changed, 40 insertions(+), 4 deletions(-) diff --git a/builtin/index-pack.c b/builtin/index-pack.c index b9f6e12..1bac0f5 100644 --- a/builtin/index-pack.c +++ b/builtin/index-pack.c @@ -542,7 +542,7 @@ static void *unpack_data(struct object_entry *obj, do { ssize_t n = (len < 64*1024) ? len : 64*1024; - n = pread(pack_fd, inbuf, n, from); + n = xpread(pack_fd, inbuf, n, from); if (n < 0) die_errno(_("cannot pread pack file")); if (!n) diff --git a/compat/mmap.c b/compat/mmap.c index c9d46d1..7f662fe 100644 --- a/compat/mmap.c +++ b/compat/mmap.c @@ -14,7 +14,7 @@ void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t of } while (n < length) { - ssize_t count = pread(fd, (char *)start + n, length - n, offset + n); + ssize_t count = xpread(fd, (char *)start + n, length - n, offset + n); if (count == 0) { memset((char *)start+n, 0, length-n); @@ -22,8 +22,6 @@ void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t of } if (count < 0) { - if (errno == EAGAIN || errno == EINTR) - continue; free(start); errno = EACCES; return MAP_FAILED; diff --git a/git-compat-util.h b/git-compat-util.h index f6d3a46..4da04c6 100644 --- a/git-compat-util.h +++ b/git-compat-util.h @@ -531,6 +531,8 @@ extern void *xcalloc(size_t nmemb, size_t size); extern void *xmmap(void *start, size_t length, int prot, int flags, int fd, off_t offset); extern ssize_t xread(int fd, void *buf, size_t len); extern ssize_t xwrite(int fd, const void *buf, size_t len); +extern ssize_t xpread(int fd, void *buf, size_t len, off_t offset); +extern ssize_t xpwrite(int fd, const void *buf, size_t len, off_t offset); extern int xdup(int fd); extern FILE *xfdopen(int fd, const char *mode); extern int xmkstemp(char *template); diff --git a/wrapper.c b/wrapper.c index 0cc5636..25b7419 100644 --- a/wrapper.c +++ b/wrapper.c @@ -174,6 +174,42 @@ ssize_t xwrite(int fd, const void *buf, size_t len) } } +/* + * xpread() is the same as pread(), but it automatically restarts pread() + * operations with a recoverable error (EAGAIN and EINTR). xpread() DOES + * NOT GUARANTEE that "len" bytes is read even if the data is available. + */ +ssize_t xpread(int fd, void *buf, size_t len, off_t offset) +{ + ssize_t nr; + if (len > MAX_IO_SIZE) + len = MAX_IO_SIZE; + while (1) { + nr = pread(fd, buf, len, offset); + if ((nr < 0) && (errno == EAGAIN || errno == EINTR)) + continue; + return nr; + } +} + +/* + * xpwrite() is the same as pwrite(), but it automatically restarts pwrite() + * operations with a recoverable error (EAGAIN and EINTR). xpwrite() DOES NOT + * GUARANTEE that "len" bytes is written even if the operation is successful. + */ +ssize_t xpwrite(int fd, const void *buf, size_t len, off_t offset) +{ + ssize_t nr; + if (len > MAX_IO_SIZE) + len = MAX_IO_SIZE; + while (1) { + nr = pwrite(fd, buf, len, offset); + if ((nr < 0) && (errno == EAGAIN || errno == EINTR)) + continue; + return nr; + } +} + ssize_t read_in_full(int fd, void *buf, size_t count) { char *p = buf; -- 1.9.1