bb_full_fd_action: remove potential xmalloc from NOFORK path

cat: stop using stdio.h opens
libbb: introduce & use open[3]_or_warn
function                                             old     new   delta
open3_or_warn                                          -      54     +54
bb_cat                                               115     144     +29
open_or_warn                                           -      25     +25
unlzma                                              2404    2412      +8
chattr_main                                          334     339      +5
xstrtoul_range_sfx                                   251     255      +4
telnet_main                                         1514    1510      -4
static.opt                                             4       -      -4
qgravechar                                           122     118      -4
fuser_add_pid                                         61      54      -7
fuser_add_inode                                      154     147      -7
writeFileToTarball                                  1542    1534      -8
refresh                                             1156    1148      -8
do_show                                              856     846     -10
read_leases                                          212     200     -12
setup_redirects                                      236     222     -14
iproute_list_or_flush                               1582    1568     -14
read_config                                          427     411     -16
write_leases                                         284     264     -20
hash_file                                            338     318     -20
copy_file                                           1760    1740     -20
do_iproute                                          2610    2588     -22
bb_full_fd_action                                    320     269     -51
open_to_or_warn                                      103      49     -54
fuser_main                                          1660    1596     -64
.rodata                                           131160  131096     -64
------------------------------------------------------------------------------
(add/remove: 2/1 grow/shrink: 4/19 up/down: 125/-423)        Total: -298 bytes

20 files changed, 183 insertions, 162 deletions

diff --git a/archival/bbunzip.c b/archival/bbunzip.c
index 3c3cc2886..4dba498b8 100644
--- a/archival/bbunzip.c
+++ b/archival/bbunzip.c
@@ -20,16 +20,11 @@ enum {
 static
 int open_to_or_warn(int to_fd, const char *filename, int flags, int mode)
 {
-	int fd = open(filename, flags, mode);
+	int fd = open3_or_warn(filename, flags, mode);
 	if (fd < 0) {
-		bb_perror_msg("%s", filename);
 		return 1;
 	}
-	if (fd != to_fd) {
-		if (dup2(fd, to_fd) < 0)
-			bb_perror_msg_and_die("cannot dup");
-		close(fd);
-	}
+	xmove_fd(fd, to_fd);
 	return 0;
 }
 
diff --git a/archival/tar.c b/archival/tar.c
index f2f1ccd06..11a74dfe9 100644
--- a/archival/tar.c
+++ b/archival/tar.c
@@ -440,9 +440,8 @@ static int writeFileToTarball(const char *fileName, struct stat *statbuf,
 	/* Is this a regular file? */
 	if (tbInfo->hlInfo == NULL && S_ISREG(statbuf->st_mode)) {
 		/* open the file we want to archive, and make sure all is well */
-		inputFileFd = open(fileName, O_RDONLY);
+		inputFileFd = open_or_warn(fileName, O_RDONLY);
 		if (inputFileFd < 0) {
-			bb_perror_msg("%s: cannot open", fileName);
 			return FALSE;
 		}
 	}
@@ -455,7 +454,7 @@ static int writeFileToTarball(const char *fileName, struct stat *statbuf,
 	/* If it was a regular file, write out the body */
 	if (inputFileFd >= 0) {
 		size_t readSize;
-		/* Wwrite the file to the archive. */
+		/* Write the file to the archive. */
 		/* We record size into header first, */
 		/* and then write out file. If file shrinks in between, */
 		/* tar will be corrupted. So we don't allow for that. */
diff --git a/coreutils/cat.c b/coreutils/cat.c
index eb141dc79..ed3f33650 100644
--- a/coreutils/cat.c
+++ b/coreutils/cat.c
@@ -19,18 +19,21 @@ int bb_cat(char **argv)
 {
 	static const char *const argv_dash[] = { "-", NULL };
 
-	FILE *f;
+	int fd;
 	int retval = EXIT_SUCCESS;
 
 	if (!*argv)
 		argv = (char**) &argv_dash;
 
 	do {
-		f = fopen_or_warn_stdin(*argv);
-		if (f) {
+		fd = STDIN_FILENO;
+		if (!LONE_DASH(*argv))
+			fd = open_or_warn(*argv, O_RDONLY);
+		if (fd >= 0) {
 			/* This is not an xfunc - never exits */
-			off_t r = bb_copyfd_eof(fileno(f), STDOUT_FILENO);
-			fclose_if_not_stdin(f);
+			off_t r = bb_copyfd_eof(fd, STDOUT_FILENO);
+			if (fd != STDIN_FILENO)
+				close(fd);
 			if (r >= 0)
 				continue;
 		}
diff --git a/coreutils/dos2unix.c b/coreutils/dos2unix.c
index 1d35d524a..04c56ac9c 100644
--- a/coreutils/dos2unix.c
+++ b/coreutils/dos2unix.c
@@ -30,7 +30,7 @@ static int convert(char *fn)
 		/*
 		   The file is then created with mode read/write and
 		   permissions 0666 for glibc 2.0.6 and earlier or
-		   0600  for glibc  2.0.7 and  later.
+		   0600 for glibc 2.0.7 and later.
 		 */
 		snprintf(bb_common_bufsiz1, sizeof(bb_common_bufsiz1), "%sXXXXXX", fn);
 		/*
@@ -38,8 +38,8 @@ static int convert(char *fn)
 		   hold the full path.  However if the output is truncated the
 		   subsequent call to mkstemp would fail.
 		 */
-		if ((i = mkstemp(&bb_common_bufsiz1[0])) == -1
-			|| chmod(bb_common_bufsiz1, 0600) == -1) {
+		i = mkstemp(&bb_common_bufsiz1[0]);
+		if (i == -1 || chmod(bb_common_bufsiz1, 0600) == -1) {
 			bb_perror_nomsg_and_die();
 		}
 		out = fdopen(i, "w+");
diff --git a/coreutils/md5_sha1_sum.c b/coreutils/md5_sha1_sum.c
index 417e90b00..a3818d519 100644
--- a/coreutils/md5_sha1_sum.c
+++ b/coreutils/md5_sha1_sum.c
@@ -38,9 +38,8 @@ static uint8_t *hash_file(const char *filename, hash_algo_t hash_algo)
 
 	src_fd = STDIN_FILENO;
 	if (NOT_LONE_DASH(filename)) {
-		src_fd = open(filename, O_RDONLY);
+		src_fd = open_or_warn(filename, O_RDONLY);
 		if (src_fd < 0) {
-			bb_perror_msg("%s", filename);
 			return NULL;
 		}
 	}
diff --git a/e2fsprogs/fsck.c b/e2fsprogs/fsck.c
index cf7f6f070..446541e84 100644
--- a/e2fsprogs/fsck.c
+++ b/e2fsprogs/fsck.c
@@ -396,7 +396,6 @@ static void load_fs_info(const char *filename)
 
 	f = fopen_or_warn(filename, "r");
 	if (f == NULL) {
-		/*bb_perror_msg("WARNING: cannot open %s", filename);*/
 		return;
 	}
 	while (1) {
diff --git a/include/libbb.h b/include/libbb.h
index c3baf9e7c..e8f1cf653 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -288,6 +288,8 @@ void xunlink(const char *pathname);
 void xstat(const char *pathname, struct stat *buf);
 int xopen(const char *pathname, int flags);
 int xopen3(const char *pathname, int flags, int mode);
+int open_or_warn(const char *pathname, int flags);
+int open3_or_warn(const char *pathname, int flags, int mode);
 off_t xlseek(int fd, off_t offset, int whence);
 off_t fdlength(int fd);
 
diff --git a/libbb/copy_file.c b/libbb/copy_file.c
index 7d85920d9..700564212 100644
--- a/libbb/copy_file.c
+++ b/libbb/copy_file.c
@@ -217,9 +217,8 @@ int copy_file(const char *source, const char *dest, int flags)
 			add_to_ino_dev_hashtable(&source_stat, dest);
 		}
 
-		src_fd = open(source, O_RDONLY);
-		if (src_fd == -1) {
-			bb_perror_msg("cannot open '%s'", source);
+		src_fd = open_or_warn(source, O_RDONLY);
+		if (src_fd < 0) {
 			return -1;
 		}
 
@@ -237,9 +236,8 @@ int copy_file(const char *source, const char *dest, int flags)
 				return ovr;
 			}
 			/* It shouldn't exist. If it exists, do not open (symlink attack?) */
-			dst_fd = open(dest, O_WRONLY|O_CREAT|O_EXCL, source_stat.st_mode);
-			if (dst_fd == -1) {
-				bb_perror_msg("cannot open '%s'", dest);
+			dst_fd = open3_or_warn(dest, O_WRONLY|O_CREAT|O_EXCL, source_stat.st_mode);
+			if (dst_fd < 0) {
 				close(src_fd);
 				return -1;
 			}
diff --git a/libbb/copyfd.c b/libbb/copyfd.c
index aa8fbb967..3255e424a 100644
--- a/libbb/copyfd.c
+++ b/libbb/copyfd.c
@@ -14,14 +14,13 @@
 #define BUFSIZ 4096
 #endif
 
-/* Used by NOFORK applets (e.g. cat) - must be very careful
- * when calling xfuncs, allocating memory, with signals, termios, etc... */
+/* Used by NOFORK applets (e.g. cat) - must not use xmalloc */
 
 static off_t bb_full_fd_action(int src_fd, int dst_fd, off_t size)
 {
 	int status = -1;
 	off_t total = 0;
-	RESERVE_CONFIG_BUFFER(buffer, BUFSIZ);
+	char buffer[BUFSIZ];
 
 	if (src_fd < 0)
 		goto out;
@@ -63,7 +62,6 @@ static off_t bb_full_fd_action(int src_fd, int dst_fd, off_t size)
 		}
 	}
  out:
-	RELEASE_CONFIG_BUFFER(buffer);
 	return status ? -1 : total;
 }
 
diff --git a/libbb/wfopen_input.c b/libbb/wfopen_input.c
index 7a11dacd7..1b4928e1f 100644
--- a/libbb/wfopen_input.c
+++ b/libbb/wfopen_input.c
@@ -11,7 +11,7 @@
  * is a command line arg.  Since often that arg is '-' (meaning stdin),
  * we avoid testing everywhere by consolidating things in this routine.
  *
- * Note: We also consider "" to main stdin (for 'cmp' at least).
+ * Note: we also consider "" to mean stdin (for 'cmp' at least).
  */
 
 #include "libbb.h"
diff --git a/libbb/xfuncs.c b/libbb/xfuncs.c
index dde91a2ba..870d736b3 100644
--- a/libbb/xfuncs.c
+++ b/libbb/xfuncs.c
@@ -106,31 +106,46 @@ FILE *xfopen(const char *path, const char *mode)
 {
 	FILE *fp = fopen(path, mode);
 	if (fp == NULL)
-		bb_perror_msg_and_die("%s", path);
+		bb_perror_msg_and_die("cannot open '%s'", path);
 	return fp;
 }
 
-// Die if we can't open an existing file and return an fd.
-int xopen(const char *pathname, int flags)
+// Die if we can't open a file and return a fd.
+int xopen3(const char *pathname, int flags, int mode)
 {
-	//if (ENABLE_DEBUG && (flags & O_CREAT))
-	//	bb_error_msg_and_die("xopen() with O_CREAT");
+	int ret;
+
+	ret = open(pathname, flags, mode);
+	if (ret < 0) {
+		bb_perror_msg_and_die("cannot open '%s'", pathname);
+	}
+	return ret;
+}
 
+// Die if we can't open an existing file and return a fd.
+int xopen(const char *pathname, int flags)
+{
 	return xopen3(pathname, flags, 0666);
 }
 
-// Die if we can't open a new file and return an fd.
-int xopen3(const char *pathname, int flags, int mode)
+// Warn if we can't open a file and return a fd.
+int open3_or_warn(const char *pathname, int flags, int mode)
 {
 	int ret;
 
 	ret = open(pathname, flags, mode);
 	if (ret < 0) {
-		bb_perror_msg_and_die("%s", pathname);
+		bb_perror_msg("cannot open '%s'", pathname);
 	}
 	return ret;
 }
 
+// Warn if we can't open a file and return a fd.
+int open_or_warn(const char *pathname, int flags)
+{
+	return open3_or_warn(pathname, flags, 0666);
+}
+
 void xunlink(const char *pathname)
 {
 	if (unlink(pathname))
@@ -184,6 +199,7 @@ off_t xlseek(int fd, off_t offset, int whence)
 void die_if_ferror(FILE *fp, const char *fn)
 {
 	if (ferror(fp)) {
+		/* doesn't set useful errno */
 		bb_error_msg_and_die("%s: I/O error", fn);
 	}
 }
diff --git a/miscutils/crond.c b/miscutils/crond.c
index 24aa3dcc3..c7d1a6c50 100644
--- a/miscutils/crond.c
+++ b/miscutils/crond.c
@@ -114,14 +114,14 @@ static void crondlog(const char *ctl, ...)
 		if (LogFile == 0) {
 			vsyslog(type, fmt, va);
 		} else {
+#if !ENABLE_DEBUG_CROND_OPTION
 			int logfd = open(LogFile, O_WRONLY | O_CREAT | O_APPEND, 0600);
+#else
+			int logfd = open3_or_warn(LogFile, O_WRONLY | O_CREAT | O_APPEND, 0600);
+#endif
 			if (logfd >= 0) {
 				vdprintf(logfd, fmt, va);
 				close(logfd);
-#if ENABLE_DEBUG_CROND_OPTION
-			} else {
-				bb_perror_msg("can't open log file");
-#endif
 			}
 		}
 	}
@@ -281,10 +281,9 @@ static void startlogger(void)
 	else {				/* test logfile */
 		int logfd;
 
-		if ((logfd = open(LogFile, O_WRONLY | O_CREAT | O_APPEND, 0600)) >= 0) {
+		logfd = open3_or_warn(LogFile, O_WRONLY | O_CREAT | O_APPEND, 0600);
+		if (logfd >= 0) {
 			close(logfd);
-		} else {
-			bb_perror_msg("failed to open log file '%s': ", LogFile);
 		}
 	}
 #endif
diff --git a/networking/libiproute/iproute.c b/networking/libiproute/iproute.c
index a19586c91..23d416344 100644
--- a/networking/libiproute/iproute.c
+++ b/networking/libiproute/iproute.c
@@ -484,10 +484,9 @@ static int rtnl_rtcache_request(struct rtnl_handle *rth, int family)
 static void iproute_flush_cache(void)
 {
 	static const char fn[] = "/proc/sys/net/ipv4/route/flush";
-	int flush_fd = open(fn, O_WRONLY);
+	int flush_fd = open_or_warn(fn, O_WRONLY);
 
 	if (flush_fd < 0) {
-		bb_perror_msg("cannot open '%s'", fn);
 		return;
 	}
 
diff --git a/networking/libiproute/iptunnel.c b/networking/libiproute/iptunnel.c
index 52a50993d..a2eb0ccda 100644
--- a/networking/libiproute/iptunnel.c
+++ b/networking/libiproute/iptunnel.c
@@ -426,10 +426,9 @@ static void do_tunnels_list(struct ip_tunnel_parm *p)
 	int type;
 	struct ip_tunnel_parm p1;
 	char buf[512];
-	FILE *fp = fopen("/proc/net/dev", "r");
+	FILE *fp = fopen_or_warn("/proc/net/dev", "r");
 
 	if (fp == NULL) {
-		bb_perror_msg("fopen");
 		return;
 	}
 
diff --git a/networking/udhcp/files.c b/networking/udhcp/files.c
index ab6f4a3e4..41c8717cd 100644
--- a/networking/udhcp/files.c
+++ b/networking/udhcp/files.c
@@ -311,9 +311,8 @@ int read_config(const char *file)
 		if (keywords[i].def[0])
 			keywords[i].handler(keywords[i].def, keywords[i].var);
 
-	in = fopen(file, "r");
+	in = fopen_or_warn(file, "r");
 	if (!in) {
-		bb_error_msg("cannot open config file: %s", file);
 		return 0;
 	}
 
@@ -360,9 +359,8 @@ void write_leases(void)
 	time_t curr = time(0);
 	unsigned long tmp_time;
 
-	fp = open(server_config.lease_file, O_WRONLY|O_CREAT|O_TRUNC, 0666);
+	fp = open3_or_warn(server_config.lease_file, O_WRONLY|O_CREAT|O_TRUNC, 0666);
 	if (fp < 0) {
-		bb_error_msg("cannot open %s for writing", server_config.lease_file);
 		return;
 	}
 
@@ -401,9 +399,8 @@ void read_leases(const char *file)
 	unsigned int i = 0;
 	struct dhcpOfferedAddr lease;
 
-	fp = open(file, O_RDONLY);
+	fp = open_or_warn(file, O_RDONLY);
 	if (fp < 0) {
-		bb_error_msg("cannot open %s for reading", file);
 		return;
 	}
 
diff --git a/procps/fuser.c b/procps/fuser.c
index c91ae217b..40789dd5e 100644
--- a/procps/fuser.c
+++ b/procps/fuser.c
@@ -34,19 +34,19 @@ static int fuser_option(char *option)
 {
 	int opt = 0;
 
-	if(!(strlen(option))) return 0;
-	if(option[0] != '-') return 0;
+	if (!option[0])
+		return 0;
+	if (option[0] != '-')
+		return 0;
 	++option;
-	while(*option != '\0') {
-		if(*option == 'm') opt |= FUSER_OPT_MOUNT;
-		else if(*option == 'k') opt |= FUSER_OPT_KILL;
-		else if(*option == 's') opt |= FUSER_OPT_SILENT;
-		else if(*option == '6') opt |= FUSER_OPT_IP6;
-		else if(*option == '4') opt |= FUSER_OPT_IP4;
-		else {
-			bb_error_msg_and_die(
-				"Unsupported option '%c'", *option);
-		}
+	while (*option != '\0') {
+		if (*option == 'm') opt |= FUSER_OPT_MOUNT;
+		else if (*option == 'k') opt |= FUSER_OPT_KILL;
+		else if (*option == 's') opt |= FUSER_OPT_SILENT;
+		else if (*option == '6') opt |= FUSER_OPT_IP6;
+		else if (*option == '4') opt |= FUSER_OPT_IP4;
+		else
+			bb_error_msg_and_die("unsupported option '%c'", *option);
 		++option;
 	}
 	return opt;
@@ -56,7 +56,8 @@ static int fuser_file_to_dev_inode(const char *filename,
 	 dev_t *dev, ino_t *inode)
 {
 	struct stat f_stat;
-	if((stat(filename, &f_stat)) < 0) return 0;
+	if ((stat(filename, &f_stat)) < 0)
+		return 0;
 	*inode = f_stat.st_ino;
 	*dev = f_stat.st_dev;
 	return 1;
@@ -68,7 +69,7 @@ static int fuser_find_socket_dev(dev_t *dev)
 	struct stat buf;
 
 	if (fd >= 0 && (fstat(fd, &buf)) == 0) {
-		*dev =  buf.st_dev;
+		*dev = buf.st_dev;
 		close(fd);
 		return 1;
 	}
@@ -80,9 +81,11 @@ static int fuser_parse_net_arg(const char *filename,
 {
 	char path[sizeof(FUSER_PROC_DIR)+12], tproto[5];
 
-	if((sscanf(filename, "%d/%4s", port, tproto)) != 2) return 0;
-	sprintf(path, "%s/net/%s", FUSER_PROC_DIR, tproto);
-	if((access(path, R_OK)) != 0) return 0;
+	if ((sscanf(filename, "%d/%4s", port, tproto)) != 2)
+		return 0;
+	sprintf(path, FUSER_PROC_DIR "/net/%s", tproto);
+	if ((access(path, R_OK)) != 0)
+		return 0;
 	*proto = xstrdup(tproto);
 	return 1;
 }
@@ -91,17 +94,19 @@ static int fuser_add_pid(pid_list *plist, pid_t pid)
 {
 	pid_list *curr = NULL, *last = NULL;
 
-	if(plist->pid == 0) plist->pid = pid;
+	if (plist->pid == 0)
+		plist->pid = pid;
 	curr = plist;
-	while(curr != NULL) {
-		if(curr->pid == pid) return 1;
+	while (curr != NULL) {
+		if (curr->pid == pid)
+			return 1;
 		last = curr;
 		curr = curr->next;
 	}
-	curr = xmalloc(sizeof(pid_list));
+	curr = xzalloc(sizeof(pid_list));
 	last->next = curr;
 	curr->pid = pid;
-	curr->next = NULL;
+	/*curr->next = NULL;*/
 	return 1;
 }
 
@@ -109,21 +114,22 @@ static int fuser_add_inode(inode_list *ilist, dev_t dev, ino_t inode)
 {
 	inode_list *curr = NULL, *last = NULL;
 
-	if(!ilist->inode && !ilist->dev) {
+	if (!ilist->inode && !ilist->dev) {
 		ilist->dev = dev;
 		ilist->inode = inode;
 	}
 	curr = ilist;
-	while(curr != NULL) {
-		if(curr->inode == inode && curr->dev == dev) return 1;
+	while (curr != NULL) {
+		if (curr->inode == inode && curr->dev == dev)
+			return 1;
 		last = curr;
 		curr = curr->next;
 	}
-	curr = xmalloc(sizeof(inode_list));
+	curr = xzalloc(sizeof(inode_list));
 	last->next = curr;
 	curr->dev = dev;
 	curr->inode = inode;
-	curr->next = NULL;
+	/*curr->next = NULL;*/
 	return 1;
 }
 
@@ -134,29 +140,31 @@ static int fuser_scan_proc_net(int opts, const char *proto,
 	char addr[128];
 	ino_t tmp_inode;
 	dev_t tmp_dev;
-	long long  uint64_inode;
+	long long uint64_inode;
 	int tmp_port;
 	FILE *f;
 
-	if(!fuser_find_socket_dev(&tmp_dev)) tmp_dev = 0;
-	sprintf(path, "%s/net/%s", FUSER_PROC_DIR, proto);
-
-	if (!(f = fopen(path, "r"))) return 0;
-	while(fgets(line, FUSER_MAX_LINE, f)) {
-		if(sscanf(line,
-			"%*d: %64[0-9A-Fa-f]:%x %*x:%*x %*x %*x:%*x "
-			"%*x:%*x %*x %*d %*d %llu",
-			addr, &tmp_port, &uint64_inode) == 3) {
-			if((strlen(addr) == 8) &&
-				(opts & FUSER_OPT_IP6)) continue;
-			else if((strlen(addr) > 8) &&
-				(opts & FUSER_OPT_IP4)) continue;
-			if(tmp_port == port) {
+	if (!fuser_find_socket_dev(&tmp_dev))
+		tmp_dev = 0;
+	sprintf(path, FUSER_PROC_DIR "/net/%s", proto);
+
+	f = fopen(path, "r");
+	if (!f)
+		return 0;
+	while (fgets(line, FUSER_MAX_LINE, f)) {
+		if (sscanf(line, "%*d: %64[0-9A-Fa-f]:%x %*x:%*x %*x %*x:%*x "
+				"%*x:%*x %*x %*d %*d %llu",
+				addr, &tmp_port, &uint64_inode) == 3
+		) {
+			if (strlen(addr) == 8 && (opts & FUSER_OPT_IP6))
+				continue;
+			if (strlen(addr) > 8 && (opts & FUSER_OPT_IP4))
+				continue;
+			if (tmp_port == port) {
 				tmp_inode = uint64_inode;
 				fuser_add_inode(ilist, tmp_dev, tmp_inode);
 			}
 		}
-
 	}
 	fclose(f);
 	return 1;
@@ -168,10 +176,10 @@ static int fuser_search_dev_inode(int opts, inode_list *ilist,
 	inode_list *curr;
 	curr = ilist;
 
-	while(curr) {
-		if((opts & FUSER_OPT_MOUNT) &&  curr->dev == dev)
+	while (curr) {
+		if ((opts & FUSER_OPT_MOUNT) && curr->dev == dev)
 			return 1;
-		if(curr->inode == inode && curr->dev == dev)
+		if (curr->inode == inode && curr->dev == dev)
 			return 1;
 		curr = curr->next;
 	}
@@ -188,17 +196,19 @@ static int fuser_scan_pid_maps(int opts, const char *fname, pid_t pid,
 	long long uint64_inode;
 	dev_t dev;
 
-	if (!(file = fopen(fname, "r"))) return 0;
+	file = fopen(fname, "r");
+	if (!file)
+		return 0;
 	while (fgets(line, FUSER_MAX_LINE, file)) {
-		if(sscanf(line, "%*s %*s %*s %x:%x %llu",
-			&major, &minor, &uint64_inode) != 3) continue;
+		if (sscanf(line, "%*s %*s %*s %x:%x %llu", &major, &minor, &uint64_inode) != 3)
+			continue;
 		inode = uint64_inode;
-		if(major == 0 && minor == 0 && inode == 0) continue;
+		if (major == 0 && minor == 0 && inode == 0)
+			continue;
 		dev = makedev(major, minor);
-		if(fuser_search_dev_inode(opts, ilist, dev, inode)) {
+		if (fuser_search_dev_inode(opts, ilist, dev, inode)) {
 			fuser_add_pid(plist, pid);
 		}
-
 	}
 	fclose(file);
 	return 1;
@@ -210,8 +220,9 @@ static int fuser_scan_link(int opts, const char *lname, pid_t pid,
 	ino_t inode;
 	dev_t dev;
 
-	if(!fuser_file_to_dev_inode(lname, &dev, &inode)) return 0;
-	if(fuser_search_dev_inode(opts, ilist, dev, inode))
+	if (!fuser_file_to_dev_inode(lname, &dev, &inode))
+		return 0;
+	if (fuser_search_dev_inode(opts, ilist, dev, inode))
 		fuser_add_pid(plist, pid);
 	return 1;
 }
@@ -223,19 +234,18 @@ static int fuser_scan_dir_links(int opts, const char *dname, pid_t pid,
 	struct dirent *de;
 	char *lname;
 
-	if((d = opendir(dname))) {
-		while((de = readdir(d)) != NULL) {
-			lname = concat_subpath_file(dname, de->d_name);
-			if(lname == NULL)
-				continue;
-			fuser_scan_link(opts, lname, pid, ilist, plist);
-			free(lname);
-		}
-		closedir(d);
+	d = opendir(dname);
+	if (!d)
+		return 0;
+	while ((de = readdir(d)) != NULL) {
+		lname = concat_subpath_file(dname, de->d_name);
+		if (lname == NULL)
+			continue;
+		fuser_scan_link(opts, lname, pid, ilist, plist);
+		free(lname);
 	}
-	else return 0;
+	closedir(d);
 	return 1;
-
 }
 
 static int fuser_scan_proc_pids(int opts, inode_list *ilist, pid_list *plist)
@@ -245,12 +255,15 @@ static int fuser_scan_proc_pids(int opts, inode_list *ilist, pid_list *plist)
 	pid_t pid;
 	char *dname;
 
-	if(!(d = opendir(FUSER_PROC_DIR))) return 0;
-	while((de = readdir(d)) != NULL) {
+	d = opendir(FUSER_PROC_DIR);
+	if (!d)
+		return 0;
+	while ((de = readdir(d)) != NULL) {
 		pid = (pid_t)atoi(de->d_name);
-		if(!pid) continue;
+		if (!pid)
+			continue;
 		dname = concat_subpath_file(FUSER_PROC_DIR, de->d_name);
-		if(chdir(dname) < 0) {
+		if (chdir(dname) < 0) {
 			free(dname);
 			continue;
 		}
@@ -272,9 +285,11 @@ static int fuser_print_pid_list(pid_list *plist)
 {
 	pid_list *curr = plist;
 
-	if(plist == NULL) return 0;
-	while(curr != NULL) {
-		if(curr->pid > 0) printf("%d ", curr->pid);
+	if (plist == NULL)
+		return 0;
+	while (curr != NULL) {
+		if (curr->pid > 0)
+			printf("%d ", curr->pid);
 		curr = curr->next;
 	}
 	puts("");
@@ -287,12 +302,12 @@ static int fuser_kill_pid_list(pid_list *plist, int sig)
 	pid_t mypid = getpid();
 	int success = 1;
 
-	if(plist == NULL) return 0;
-	while(curr != NULL) {
-		if(curr->pid > 0 && curr->pid != mypid) {
+	if (plist == NULL)
+		return 0;
+	while (curr != NULL) {
+		if (curr->pid > 0 && curr->pid != mypid) {
 			if (kill(curr->pid, sig) != 0) {
-				bb_perror_msg(
-					"cannot kill pid '%d'", curr->pid);
+				bb_perror_msg("kill pid '%d'", curr->pid);
 				success = 0;
 			}
 		}
@@ -304,11 +319,12 @@ static int fuser_kill_pid_list(pid_list *plist, int sig)
 int fuser_main(int argc, char **argv);
 int fuser_main(int argc, char **argv)
 {
+	/*static -- huh???*/ int opt = 0; /* FUSER_OPT_ */
+
 	int port, i, optn;
 	int* fni; /* file name indexes of argv */
 	int fnic = 0;  /* file name index count */
 	const char *proto;
-	static int opt = 0; /* FUSER_OPT_ */
 	dev_t dev;
 	ino_t inode;
 	pid_list *pids;
@@ -320,30 +336,31 @@ int fuser_main(int argc, char **argv)
 		bb_show_usage();
 
 	fni = xmalloc(sizeof(int));
-	for (i=1;i<argc;i++) {
+	for (i = 1; i < argc; i++) {
 		optn = fuser_option(argv[i]);
-		if(optn) opt |= optn;
-		else if(argv[i][0] == '-') {
+		if (optn)
+			opt |= optn;
+		else if (argv[i][0] == '-') {
 			killsig = get_signum(argv[i]+1);
-			if(0 > killsig)
+			if (killsig < 0)
 				killsig = SIGTERM;
-		}
-		else {
+		} else {
 			fni = xrealloc(fni, sizeof(int) * (fnic+2));
 			fni[fnic++] = i;
 		}
 	}
-	if(!fnic) return 1;
+
+	if (!fnic)
+		return 1;
 
 	inodes = xmalloc(sizeof(inode_list));
-	for (i=0;i<fnic;i++) {
-		if(fuser_parse_net_arg(argv[fni[i]], &proto, &port)) {
+	for (i = 0; i < fnic; i++) {
+		if (fuser_parse_net_arg(argv[fni[i]], &proto, &port)) {
 			fuser_scan_proc_net(opt, proto, port, inodes);
-		}
-		else {
-			if(!fuser_file_to_dev_inode(
-				argv[fni[i]], &dev, &inode)) {
-				if (ENABLE_FEATURE_CLEAN_UP) free(inodes);
+		} else {
+			if (!fuser_file_to_dev_inode(argv[fni[i]], &dev, &inode)) {
+				if (ENABLE_FEATURE_CLEAN_UP)
+					free(inodes);
 				bb_perror_msg_and_die("cannot open '%s'", argv[fni[i]]);
 			}
 			fuser_add_inode(inodes, dev, inode);
@@ -352,17 +369,19 @@ int fuser_main(int argc, char **argv)
 	pids = xmalloc(sizeof(pid_list));
 	success = fuser_scan_proc_pids(opt, inodes, pids);
 	/* if the first pid in the list is 0, none have been found */
-	if(pids->pid == 0) success = 0;
-	if(success) {
-		if(opt & FUSER_OPT_KILL) {
+	if (pids->pid == 0)
+		success = 0;
+	if (success) {
+		if (opt & FUSER_OPT_KILL) {
 			success = fuser_kill_pid_list(pids, killsig);
-		}
-		else if(!(opt & FUSER_OPT_SILENT)) {
+		} else if (!(opt & FUSER_OPT_SILENT)) {
 			success = fuser_print_pid_list(pids);
 		}
 	}
-	free(pids);
-	free(inodes);
+	if (ENABLE_FEATURE_CLEAN_UP) {
+		free(pids);
+		free(inodes);
+	}
 	/* return 0 on (success == 1) 1 otherwise */
 	return (success != 1);
 }
diff --git a/procps/sysctl.c b/procps/sysctl.c
index b5a01894f..7c72ac933 100644
--- a/procps/sysctl.c
+++ b/procps/sysctl.c
@@ -202,7 +202,8 @@ int sysctl_write_setting(const char *setting, int output)
 	while ((cptr = strchr(outname, '/')) != NULL)
 		*cptr = '.';
 
-	if ((fd = open(tmpname, O_WRONLY | O_CREAT | O_TRUNC, 0666)) < 0) {
+	fd = open(tmpname, O_WRONLY | O_CREAT | O_TRUNC, 0666);
+	if (fd < 0) {
 		switch (errno) {
 		case ENOENT:
 			bb_error_msg(ERR_INVALID_KEY, outname);
diff --git a/shell/hush.c b/shell/hush.c
index 331d591c8..1ad61e54e 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -1019,11 +1019,10 @@ static int setup_redirects(struct child_prog *prog, int squirrel[])
 		}
 		if (redir->dup == -1) {
 			mode = redir_table[redir->type].mode;
-			openfd = open(redir->word.gl_pathv[0], mode, 0666);
+			openfd = open3_or_warn(redir->word.gl_pathv[0], mode, 0666);
 			if (openfd < 0) {
 			/* this could get lost if stderr has been redirected, but
 			   bash and ash both lose it as well (though zsh doesn't!) */
-				bb_perror_msg("error opening %s", redir->word.gl_pathv[0]);
 				return 1;
 			}
 		} else {
diff --git a/shell/lash.c b/shell/lash.c
index aba9c0a2e..c72a65639 100644
--- a/shell/lash.c
+++ b/shell/lash.c
@@ -571,11 +571,10 @@ static int setup_redirects(struct child_prog *prog, int squirrel[])
 			break;
 		}
 
-		openfd = open(redir->filename, mode, 0666);
+		openfd = open3_or_warn(redir->filename, mode, 0666);
 		if (openfd < 0) {
 			/* this could get lost if stderr has been redirected, but
 			   bash and ash both lose it as well (though zsh doesn't!) */
-			bb_perror_msg("error opening %s", redir->filename);
 			return 1;
 		}
 
diff --git a/util-linux/switch_root.c b/util-linux/switch_root.c
index 43c2a6991..43377e16e 100644
--- a/util-linux/switch_root.c
+++ b/util-linux/switch_root.c
@@ -111,7 +111,7 @@ int switch_root_main(int argc, char **argv)
 
 	if (console) {
 		close(0);
-		if(open(console, O_RDWR) < 0)
+		if (open(console, O_RDWR) < 0)
 			bb_error_msg_and_die("bad console '%s'", console);
 		dup2(0, 1);
 		dup2(0, 2);