# --- T2-COPYRIGHT-BEGIN --- # t2/package/*/lvm2/fix-stdio-usage.patch.musl # Copyright (C) 2024 - 2026 The T2 SDE Project # SPDX-License-Identifier: GPL-2.0 or patched project license # --- T2-COPYRIGHT-END --- From c2817ff30c4ad1e1a171ee0e914dbecdd486e3cf Mon Sep 17 00:00:00 2001 From: David Seifert Date: Sat, 28 Jan 2023 14:22:42 +0100 Subject: [PATCH] Use `freopen()` on {stdin,stdout,stderr} * ISO C does not guarantee that the standard streams are modifiable lvalues. Glibc even calls out this behaviour as non-portable: https://www.gnu.org/software/libc/manual/html_node/Standard-Streams.html --- lib/log/log.c | 2 +- tools/lvmcmdline.c | 6 +++--- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/lib/log/log.c b/lib/log/log.c index 118a3ba42..aecc72611 100644 --- a/lib/log/log.c +++ b/lib/log/log.c @@ -208,7 +208,7 @@ int reopen_standard_stream(FILE **stream, const char *mode) _check_and_replace_standard_log_streams(old_stream, new_stream); - *stream = new_stream; + freopen(NULL, mode, *stream); return 1; } diff --git a/tools/lvmcmdline.c b/tools/lvmcmdline.c index a5bb6a5c5..0ebfa375c 100644 --- a/tools/lvmcmdline.c +++ b/tools/lvmcmdline.c @@ -3422,7 +3422,7 @@ static int _check_standard_fds(void) int err = is_valid_fd(STDERR_FILENO); if (!is_valid_fd(STDIN_FILENO) && - !(stdin = fopen(_PATH_DEVNULL, "r"))) { + !freopen(_PATH_DEVNULL, "r", stdin)) { if (err) perror("stdin stream open"); else @@ -3432,7 +3432,7 @@ static int _check_standard_fds(void) } if (!is_valid_fd(STDOUT_FILENO) && - !(stdout = fopen(_PATH_DEVNULL, "w"))) { + !freopen(_PATH_DEVNULL, "w", stdout)) { if (err) perror("stdout stream open"); /* else no stdout */ @@ -3440,7 +3440,7 @@ static int _check_standard_fds(void) } if (!is_valid_fd(STDERR_FILENO) && - !(stderr = fopen(_PATH_DEVNULL, "w"))) { + !freopen(_PATH_DEVNULL, "w", stderr)) { printf("stderr stream open: %s\n", strerror(errno)); return 0; -- 2.39.1