File 0001-toolcontext-Only-reopen-stdin-if-readable.patch of Package lvm2.1005

From 78647da1c66106e3e8f310cd37742d196e195c96 Mon Sep 17 00:00:00 2001
From: Alasdair G Kergon <agk@redhat.com>
Date: Wed, 28 Aug 2013 23:55:14 +0100
Subject: toolcontext: Only reopen stdin if readable.
Git-repo: https://git.fedorahosted.org/git/lvm2.git
Git-commit: 78647da1c66106e3e8f310cd37742d196e195c96 (partial)
Patch-filtered: skipped WHATS_NEW

Don't fail when running lvm commands under versions of nohup that set
up stdin as O_WRONLY!
---

 lib/commands/toolcontext.c |   19 +++++++++++++++----
 1 file changed, 15 insertions(+), 4 deletions(-)

diff --git a/lib/commands/toolcontext.c b/lib/commands/toolcontext.c
index 702a2d8..4f53f0e 100644
--- a/lib/commands/toolcontext.c
+++ b/lib/commands/toolcontext.c
@@ -1372,6 +1372,7 @@ struct cmd_context *create_toolcontext(unsigned is_long_lived,
 {
 	struct cmd_context *cmd;
 	FILE *new_stream;
+	int flags;
 
 #ifdef M_MMAP_MAX
 	mallopt(M_MMAP_MAX, 0);
@@ -1415,7 +1416,10 @@ struct cmd_context *create_toolcontext(unsigned is_long_lived,
 			goto out;
 		}
 
-		if (is_valid_fd(STDIN_FILENO)) {
+		/* nohup might set stdin O_WRONLY ! */
+		if (is_valid_fd(STDIN_FILENO) &&
+		    ((flags = fcntl(STDIN_FILENO, F_GETFL)) > 0) &&
+		    (flags & O_ACCMODE) != O_WRONLY) {
 			if (!_reopen_stream(stdin, STDIN_FILENO, "r", "stdin", &new_stream))
 				goto_out;
 			stdin = new_stream;
@@ -1425,7 +1429,9 @@ struct cmd_context *create_toolcontext(unsigned is_long_lived,
 			}
 		}
 
-		if (is_valid_fd(STDOUT_FILENO)) {
+		if (is_valid_fd(STDOUT_FILENO) &&
+		    ((flags = fcntl(STDOUT_FILENO, F_GETFL)) > 0) &&
+		    (flags & O_ACCMODE) != O_RDONLY) {
 			if (!_reopen_stream(stdout, STDOUT_FILENO, "w", "stdout", &new_stream))
 				goto_out;
 			stdout = new_stream;
@@ -1709,6 +1715,7 @@ void destroy_toolcontext(struct cmd_context *cmd)
 {
 	struct dm_config_tree *cft_cmdline;
 	FILE *new_stream;
+	int flags;
 
 	if (cmd->dump_filter)
 		persistent_filter_dump(cmd->filter, 1);
@@ -1741,7 +1748,9 @@ void destroy_toolcontext(struct cmd_context *cmd)
 #ifndef VALGRIND_POOL
 	if (cmd->linebuffer) {
 		/* Reset stream buffering to defaults */
-		if (is_valid_fd(STDIN_FILENO)) {
+		if (is_valid_fd(STDIN_FILENO) &&
+		    ((flags = fcntl(STDIN_FILENO, F_GETFL)) > 0) &&
+		    (flags & O_ACCMODE) != O_WRONLY) {
 			if (_reopen_stream(stdin, STDIN_FILENO, "r", "stdin", &new_stream)) {
 				stdin = new_stream;
 				setlinebuf(stdin);
@@ -1749,7 +1758,9 @@ void destroy_toolcontext(struct cmd_context *cmd)
 				cmd->linebuffer = NULL;	/* Leave buffer in place (deliberate leak) */
 		}
 
-		if (is_valid_fd(STDOUT_FILENO)) {
+		if (is_valid_fd(STDOUT_FILENO) &&
+		    ((flags = fcntl(STDOUT_FILENO, F_GETFL)) > 0) &&
+		    (flags & O_ACCMODE) != O_RDONLY) {
 			if (_reopen_stream(stdout, STDOUT_FILENO, "w", "stdout", &new_stream)) {
 				stdout = new_stream;
 				setlinebuf(stdout);