From mboxrd@z Thu Jan 1 00:00:00 1970 Delivery-date: Wed, 22 Nov 2023 17:11:08 +0100 Received: from metis.whiteo.stw.pengutronix.de ([2a0a:edc0:2:b01:1d::104]) by lore.white.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1r5poi-004YcA-10 for lore@lore.pengutronix.de; Wed, 22 Nov 2023 17:11:08 +0100 Received: from bombadil.infradead.org ([2607:7c80:54:3::133]) by metis.whiteo.stw.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1r5poi-0004wj-9i for lore@pengutronix.de; Wed, 22 Nov 2023 17:11:08 +0100 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=e2Y+9MKHFUxspImlfBjgTMIOo9ENvx3+LL6SsZXYlnk=; b=Sqg77yaNE/Fasnp+6UTqb9jFHc gt/3pk0vWtHjBoWAUHzD2YOj7WxSHVmq8AJ9FrBaOwcSACcGa0k1gBpVWaBSln083jwNvZoMIUTxU ZkgX1ItfB9vS9ZVZ5wSp6odHHmiIUI3kFI1DjtD4EW9ZEuuec/YGGFdEzxhMM7KCH5T0ZazY9JkLt doznCxgIlvY18BuThLvBRUwjoTwkQ5m8HqzkiD/1YpaWaKVZOfmEzmIQqGqUZKFpR16UTTmXL14CC I3grB4vYBw9DxUsQP9wp5smPOdDohviwD7dP2WtZsHyw71F7vbVaHx2+b20N8+JUODzy/OAMvi6yc G5bSh6IQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1r5pnN-002NzW-1l; Wed, 22 Nov 2023 16:09:45 +0000 Received: from metis.whiteo.stw.pengutronix.de ([2a0a:edc0:2:b01:1d::104]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1r5pnJ-002Nyi-1V for barebox@lists.infradead.org; Wed, 22 Nov 2023 16:09:42 +0000 Received: from ptz.office.stw.pengutronix.de ([2a0a:edc0:0:900:1d::77] helo=[127.0.0.1]) by metis.whiteo.stw.pengutronix.de with esmtp (Exim 4.92) (envelope-from ) id 1r5pnH-0004cU-J6; Wed, 22 Nov 2023 17:09:39 +0100 Message-ID: <905d5333-e2f4-0485-7483-f2f6d0ea110a@pengutronix.de> Date: Wed, 22 Nov 2023 17:09:39 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.13.0 Content-Language: en-US To: Sascha Hauer Cc: barebox@lists.infradead.org References: <20231120083750.3967831-1-a.fatoum@pengutronix.de> <20231120083750.3967831-2-a.fatoum@pengutronix.de> <20231121073622.GN3359458@pengutronix.de> From: Ahmad Fatoum In-Reply-To: <20231121073622.GN3359458@pengutronix.de> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20231122_080941_500509_74B00058 X-CRM114-Status: GOOD ( 24.69 ) X-BeenThere: barebox@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "barebox" X-SA-Exim-Connect-IP: 2607:7c80:54:3::133 X-SA-Exim-Mail-From: barebox-bounces+lore=pengutronix.de@lists.infradead.org X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on metis.whiteo.stw.pengutronix.de X-Spam-Level: X-Spam-Status: No, score=-5.8 required=4.0 tests=AWL,BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,NICE_REPLY_A,RCVD_IN_DNSWL_MED,SPF_HELO_NONE, SPF_NONE,T_SCC_BODY_TEXT_LINE autolearn=unavailable autolearn_force=no version=3.4.2 Subject: Re: [PATCH RFC 2/3] libfile: implement read_fd counterpart to read_file X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on metis.whiteo.stw.pengutronix.de) On 21.11.23 08:36, Sascha Hauer wrote: > On Mon, Nov 20, 2023 at 09:37:49AM +0100, Ahmad Fatoum wrote: >> Files opened with O_TMPFILE have no name, so read_file can't be used >> with them. Therefore add a read_fd function, which slurps all a file's >> contents into a buffer. >> >> Signed-off-by: Ahmad Fatoum >> --- >> include/libfile.h | 2 ++ >> lib/libfile.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ >> 2 files changed, 46 insertions(+) >> >> diff --git a/include/libfile.h b/include/libfile.h >> index a353ccfa9ea9..423e7ffec5b7 100644 >> --- a/include/libfile.h >> +++ b/include/libfile.h >> @@ -12,6 +12,8 @@ char *read_file_line(const char *fmt, ...); >> >> void *read_file(const char *filename, size_t *size); >> >> +void *read_fd(int fd, size_t *size); >> + >> int read_file_2(const char *filename, size_t *size, void **outbuf, >> loff_t max_size); >> >> diff --git a/lib/libfile.c b/lib/libfile.c >> index e53ba08415a2..c257baaa2733 100644 >> --- a/lib/libfile.c >> +++ b/lib/libfile.c >> @@ -306,6 +306,50 @@ void *read_file(const char *filename, size_t *size) >> } >> EXPORT_SYMBOL(read_file); >> >> +/** >> + * read_fd - read from a file descriptor to an allocated buffer >> + * @filename: The file descriptor to read >> + * @size: After successful return contains the size of the file >> + * >> + * This function reads a file descriptor from offset 0 until EOF to an >> + * allocated buffer. >> + * >> + * Return: The buffer containing the file or NULL on failure >> + */ >> +void *read_fd(int fd, size_t *out_size) >> +{ >> + off_t off; >> + ssize_t ret; >> + size_t size; >> + void *buf; >> + >> + off = lseek(fd, SEEK_CUR, 0); > > You lseek to the current position. It seems you are trying to determine > the size of the file, so did you mean to use SEEK_END? > > You could use fstat() instead. With that you could also correctly handle > FILE_SIZE_STREAM. Will use fstat, thanks. > >> + if (off >= 0) { >> + size = off; >> + off = lseek(fd, SEEK_SET, 0); >> + } >> + if (off < 0) { >> + ret = off; >> + goto close_fd; >> + } >> + >> + buf = malloc(size + 3); >> + ret = read_full(fd, buf, size); > > You can use pread_full() here to avoid having to lseek to the beginning > of the file. Ok, will do. > >> + if (ret < 0) { >> + free(buf); >> + goto close_fd; >> + } >> + >> + memset(&buf[size], '\0', 3); >> + *out_size = size; >> + >> +close_fd: >> + close(fd); >> + >> + return ret < 0 ? NULL : buf; > > Return an error pointer or an error integer and pass buf as argument? I want it to return a buffer like read_file does. I think that would be the least surprising API. Cheers, Ahmad > > Sascha > -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |