From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on gnuweeb.org X-Spam-Level: X-Spam-Status: No, score=-6.2 required=5.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_HI,SPF_HELO_NONE, SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 Authentication-Results: gnuweeb.org; dmarc=pass (p=none dis=none) header.from=kernel.org Authentication-Results: gnuweeb.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=QU+1m9++; dkim-atps=neutral Received-SPF: Pass (mailfrom) identity=mailfrom; client-ip=139.178.84.217; helo=dfw.source.kernel.org; envelope-from=srs0=wjcp=bh=paulmck-thinkpad-p17-gen-1.home=paulmck@kernel.org; receiver= Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by gnuweeb.org (Postfix) with ESMTPS id C3CD62492EC for ; Thu, 18 May 2023 21:55:26 +0700 (WIB) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 55E6564FE4; Thu, 18 May 2023 14:55:25 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B6F87C433A4; Thu, 18 May 2023 14:55:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1684421723; bh=fkkJpit5a3ZlIC5i/D5UeQi47Yy3csUMhtA5gdos6Dc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QU+1m9+++DTKwLknKSXgDJYhDjOSEeYSysSmhEB9J4WFitQ9rwKjV9y8NIHUPLGS3 RvneKXuXABUfG0Im2F/tAPTj85wlmwgCT++Kzlnq8Wcxm8hxW4bUILiSzUUGOARjZw Y3v6IZxS/HKB71Mg5D/f2FHz0ArzIUk3F2f3OzH0VjYbmpORBV5J2ZsneLVq/oan2z P9mEwOIr3diw0FSeD0nTLcASzZn8FZ0JD5pV2zjRlBbbwEefApmdJvwdn1YUzbnkCv XvGCTRqHeukfNGjJIrOsRj35ZgAxvqYx9IsvLlF0yNVUIDTS8H9Z6znM0k31py8KrS nazpcEZD5Lukg== Received: by paulmck-ThinkPad-P17-Gen-1.home (Postfix, from userid 1000) id 1F405CE142E; Thu, 18 May 2023 07:55:23 -0700 (PDT) From: "Paul E. McKenney" To: linux-kernel@vger.kernel.org Cc: gwml@vger.gnuweeb.org, kernel-team@meta.com, w@lwt.eu, =?UTF-8?q?Thomas=20Wei=C3=9Fschuh?= , Willy Tarreau , "Paul E . McKenney" Subject: [PATCH v2 nolibc 06/15] tools/nolibc: implement fd-based FILE streams Date: Thu, 18 May 2023 07:55:12 -0700 Message-Id: <20230518145521.3806117-6-paulmck@kernel.org> X-Mailer: git-send-email 2.40.1 In-Reply-To: <4817a4dc-69e6-4937-84d5-f2f630ff646c@paulmck-laptop> References: <4817a4dc-69e6-4937-84d5-f2f630ff646c@paulmck-laptop> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit List-Id: From: Thomas Weißschuh This enables the usage of the stream APIs with arbitrary filedescriptors. It will be used by a future testcase. Signed-off-by: Thomas Weißschuh Signed-off-by: Willy Tarreau Signed-off-by: Paul E. McKenney --- tools/include/nolibc/stdio.h | 95 ++++++++++++++++++++++++++---------- 1 file changed, 68 insertions(+), 27 deletions(-) diff --git a/tools/include/nolibc/stdio.h b/tools/include/nolibc/stdio.h index 6cbbb52836a0..0eef91daf289 100644 --- a/tools/include/nolibc/stdio.h +++ b/tools/include/nolibc/stdio.h @@ -21,17 +21,75 @@ #define EOF (-1) #endif -/* just define FILE as a non-empty type */ +/* just define FILE as a non-empty type. The value of the pointer gives + * the FD: FILE=~fd for fd>=0 or NULL for fd<0. This way positive FILE + * are immediately identified as abnormal entries (i.e. possible copies + * of valid pointers to something else). + */ typedef struct FILE { char dummy[1]; } FILE; -/* We define the 3 common stdio files as constant invalid pointers that - * are easily recognized. - */ -static __attribute__((unused)) FILE* const stdin = (FILE*)-3; -static __attribute__((unused)) FILE* const stdout = (FILE*)-2; -static __attribute__((unused)) FILE* const stderr = (FILE*)-1; +static __attribute__((unused)) FILE* const stdin = (FILE*)(intptr_t)~STDIN_FILENO; +static __attribute__((unused)) FILE* const stdout = (FILE*)(intptr_t)~STDOUT_FILENO; +static __attribute__((unused)) FILE* const stderr = (FILE*)(intptr_t)~STDERR_FILENO; + +/* provides a FILE* equivalent of fd. The mode is ignored. */ +static __attribute__((unused)) +FILE *fdopen(int fd, const char *mode __attribute__((unused))) +{ + if (fd < 0) { + SET_ERRNO(EBADF); + return NULL; + } + return (FILE*)(intptr_t)~fd; +} + +/* provides the fd of stream. */ +static __attribute__((unused)) +int fileno(FILE *stream) +{ + intptr_t i = (intptr_t)stream; + + if (i >= 0) { + SET_ERRNO(EBADF); + return -1; + } + return ~i; +} + +/* flush a stream. */ +static __attribute__((unused)) +int fflush(FILE *stream) +{ + intptr_t i = (intptr_t)stream; + + /* NULL is valid here. */ + if (i > 0) { + SET_ERRNO(EBADF); + return -1; + } + + /* Don't do anything, nolibc does not support buffering. */ + return 0; +} + +/* flush a stream. */ +static __attribute__((unused)) +int fclose(FILE *stream) +{ + intptr_t i = (intptr_t)stream; + + if (i >= 0) { + SET_ERRNO(EBADF); + return -1; + } + + if (close(~i)) + return EOF; + + return 0; +} /* getc(), fgetc(), getchar() */ @@ -41,14 +99,8 @@ static __attribute__((unused)) int fgetc(FILE* stream) { unsigned char ch; - int fd; - if (stream < stdin || stream > stderr) - return EOF; - - fd = 3 + (long)stream; - - if (read(fd, &ch, 1) <= 0) + if (read(fileno(stream), &ch, 1) <= 0) return EOF; return ch; } @@ -68,14 +120,8 @@ static __attribute__((unused)) int fputc(int c, FILE* stream) { unsigned char ch = c; - int fd; - - if (stream < stdin || stream > stderr) - return EOF; - - fd = 3 + (long)stream; - if (write(fd, &ch, 1) <= 0) + if (write(fileno(stream), &ch, 1) <= 0) return EOF; return ch; } @@ -96,12 +142,7 @@ static __attribute__((unused)) int _fwrite(const void *buf, size_t size, FILE *stream) { ssize_t ret; - int fd; - - if (stream < stdin || stream > stderr) - return EOF; - - fd = 3 + (long)stream; + int fd = fileno(stream); while (size) { ret = write(fd, buf, size); -- 2.40.1