*: Switch to POSIX utmpx API

UTMP is SVID legacy, UTMPX is mandated by POSIX.

Glibc and uClibc have identical layout of UTMP and UTMPX, both of these
libc treat _PATH_UTMPX as _PATH_UTMP so from a user-perspective nothing
changes except the names of the API entrypoints.

Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>

9 files changed, 56 insertions, 52 deletions

diff --git a/coreutils/who.c b/coreutils/who.c
index f955ce6..8337212 100644
--- a/coreutils/who.c
+++ b/coreutils/who.c
@@ -73,7 +73,7 @@ static void idle_string(char *str6, time_t t)
 int who_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int who_main(int argc UNUSED_PARAM, char **argv)
 {
-	struct utmp *ut;
+	struct utmpx *ut;
 	unsigned opt;
 	int do_users = (ENABLE_USERS && (!ENABLE_WHO || applet_name[0] == 'u'));
 	const char *fmt = "%s";
@@ -83,8 +83,8 @@ int who_main(int argc UNUSED_PARAM, char **argv)
 	if (opt & 2) // -H
 		printf("USER\t\tTTY\t\tIDLE\tTIME\t\t HOST\n");
 
-	setutent();
-	while ((ut = getutent()) != NULL) {
+	setutxent();
+	while ((ut = getutxent()) != NULL) {
 		if (ut->ut_user[0]
 		 && ((opt & 1) || ut->ut_type == USER_PROCESS)
 		) {
@@ -126,6 +126,6 @@ int who_main(int argc UNUSED_PARAM, char **argv)
 	if (do_users)
 		bb_putchar('\n');
 	if (ENABLE_FEATURE_CLEAN_UP)
-		endutent();
+		endutxent();
 	return EXIT_SUCCESS;
 }
diff --git a/include/libbb.h b/include/libbb.h
index 26b6868..0f8363b 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -84,7 +84,7 @@
 # include <selinux/av_permissions.h>
 #endif
 #if ENABLE_FEATURE_UTMP
-# include <utmp.h>
+# include <utmpx.h>
 #endif
 #if ENABLE_LOCALE_SUPPORT
 # include <locale.h>
diff --git a/init/halt.c b/init/halt.c
index 7974adb..ad12d91 100644
--- a/init/halt.c
+++ b/init/halt.c
@@ -74,7 +74,7 @@
 
 static void write_wtmp(void)
 {
-	struct utmp utmp;
+	struct utmpx utmp;
 	struct utsname uts;
 	/* "man utmp" says wtmp file should *not* be created automagically */
 	/*if (access(bb_path_wtmp_file, R_OK|W_OK) == -1) {
@@ -88,7 +88,7 @@ static void write_wtmp(void)
 	utmp.ut_line[0] = '~'; utmp.ut_line[1] = '~'; /* = strcpy(utmp.ut_line, "~~"); */
 	uname(&uts);
 	safe_strncpy(utmp.ut_host, uts.release, sizeof(utmp.ut_host));
-	updwtmp(bb_path_wtmp_file, &utmp);
+	updwtmpx(bb_path_wtmp_file, &utmp);
 }
 #else
 #define write_wtmp() ((void)0)
diff --git a/libbb/utmp.c b/libbb/utmp.c
index 8ad9ba2..bd07670 100644
--- a/libbb/utmp.c
+++ b/libbb/utmp.c
@@ -16,7 +16,7 @@ static void touch(const char *filename)
 
 void FAST_FUNC write_new_utmp(pid_t pid, int new_type, const char *tty_name, const char *username, const char *hostname)
 {
-	struct utmp utent;
+	struct utmpx utent;
 	char *id;
 	unsigned width;
 
@@ -45,17 +45,17 @@ void FAST_FUNC write_new_utmp(pid_t pid, int new_type, const char *tty_name, con
 		tty_name += 3;
 	strncpy(id, tty_name, width);
 
-	touch(_PATH_UTMP);
-	//utmpname(_PATH_UTMP);
-	setutent();
+	touch(_PATH_UTMPX);
+	//utmpxname(_PATH_UTMPX);
+	setutxent();
 	/* Append new one (hopefully, unless we collide on ut_id) */
-	pututline(&utent);
-	endutent();
+	pututxline(&utent);
+	endutxent();
 
 #if ENABLE_FEATURE_WTMP
 	/* "man utmp" says wtmp file should *not* be created automagically */
 	/*touch(bb_path_wtmp_file);*/
-	updwtmp(bb_path_wtmp_file, &utent);
+	updwtmpx(bb_path_wtmp_file, &utent);
 #endif
 }
 
@@ -64,17 +64,17 @@ void FAST_FUNC write_new_utmp(pid_t pid, int new_type, const char *tty_name, con
  */
 void FAST_FUNC update_utmp(pid_t pid, int new_type, const char *tty_name, const char *username, const char *hostname)
 {
-	struct utmp utent;
-	struct utmp *utp;
+	struct utmpx utent;
+	struct utmpx *utp;
 
-	touch(_PATH_UTMP);
-	//utmpname(_PATH_UTMP);
-	setutent();
+	touch(_PATH_UTMPX);
+	//utmpxname(_PATH_UTMPX);
+	setutxent();
 
 	/* Did init/getty/telnetd/sshd/... create an entry for us?
 	 * It should be (new_type-1), but we'd also reuse
 	 * any other potentially stale xxx_PROCESS entry */
-	while ((utp = getutent()) != NULL) {
+	while ((utp = getutxent()) != NULL) {
 		if (utp->ut_pid == pid
 		// && ut->ut_line[0]
 		 && utp->ut_id[0] /* must have nonzero id */
@@ -88,25 +88,25 @@ void FAST_FUNC update_utmp(pid_t pid, int new_type, const char *tty_name, const
 				/* Stale record. Nuke hostname */
 				memset(utp->ut_host, 0, sizeof(utp->ut_host));
 			}
-			/* NB: pututline (see later) searches for matching utent
-			 * using getutid(utent) - we must not change ut_id
+			/* NB: pututxline (see later) searches for matching utxent
+			 * using getutxid(utent) - we must not change ut_id
 			 * if we want *exactly this* record to be overwritten!
 			 */
 			break;
 		}
 	}
-	//endutent(); - no need, pututline can deal with (and actually likes)
+	//endutxent(); - no need, pututxline can deal with (and actually likes)
 	//the situation when utmp file is positioned on found record
 
 	if (!utp) {
 		if (new_type != DEAD_PROCESS)
 			write_new_utmp(pid, new_type, tty_name, username, hostname);
 		else
-			endutent();
+			endutxent();
 		return;
 	}
 
-	/* Make a copy. We can't use *utp, pututline's internal getutid
+	/* Make a copy. We can't use *utp, pututxline's internal getutxid
 	 * will overwrite it before it is used! */
 	utent = *utp;
 
@@ -120,14 +120,14 @@ void FAST_FUNC update_utmp(pid_t pid, int new_type, const char *tty_name, const
 	utent.ut_tv.tv_sec = time(NULL);
 
 	/* Update, or append new one */
-	//setutent();
-	pututline(&utent);
-	endutent();
+	//setutxent();
+	pututxline(&utent);
+	endutxent();
 
 #if ENABLE_FEATURE_WTMP
 	/* "man utmp" says wtmp file should *not* be created automagically */
 	/*touch(bb_path_wtmp_file);*/
-	updwtmp(bb_path_wtmp_file, &utent);
+	updwtmpx(bb_path_wtmp_file, &utent);
 #endif
 }
 
diff --git a/miscutils/last.c b/miscutils/last.c
index a144c7e..6d8b584 100644
--- a/miscutils/last.c
+++ b/miscutils/last.c
@@ -32,21 +32,21 @@
 
 #if defined UT_LINESIZE \
 	&& ((UT_LINESIZE != 32) || (UT_NAMESIZE != 32) || (UT_HOSTSIZE != 256))
-#error struct utmp member char[] size(s) have changed!
+#error struct utmpx member char[] size(s) have changed!
 #elif defined __UT_LINESIZE \
 	&& ((__UT_LINESIZE != 32) || (__UT_NAMESIZE != 64) || (__UT_HOSTSIZE != 256))
-#error struct utmp member char[] size(s) have changed!
+#error struct utmpx member char[] size(s) have changed!
 #endif
 
 #if EMPTY != 0 || RUN_LVL != 1 || BOOT_TIME != 2 || NEW_TIME != 3 || \
 	OLD_TIME != 4
-#error Values for the ut_type field of struct utmp changed
+#error Values for the ut_type field of struct utmpx changed
 #endif
 
 int last_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int last_main(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
 {
-	struct utmp ut;
+	struct utmpx ut;
 	int n, file = STDIN_FILENO;
 	time_t t_tmp;
 	off_t pos;
diff --git a/miscutils/last_fancy.c b/miscutils/last_fancy.c
index 16ed9e9..8194e31 100644
--- a/miscutils/last_fancy.c
+++ b/miscutils/last_fancy.c
@@ -22,6 +22,10 @@
 #define HEADER_LINE_WIDE  "USER", "TTY", \
 	INET6_ADDRSTRLEN, INET6_ADDRSTRLEN, "HOST", "LOGIN", "  TIME", ""
 
+#if !defined __UT_LINESIZE && defined UT_LINESIZE
+# define __UT_LINESIZE UT_LINESIZE
+#endif
+
 enum {
 	NORMAL,
 	LOGGED,
@@ -39,7 +43,7 @@ enum {
 
 #define show_wide (option_mask32 & LAST_OPT_W)
 
-static void show_entry(struct utmp *ut, int state, time_t dur_secs)
+static void show_entry(struct utmpx *ut, int state, time_t dur_secs)
 {
 	unsigned days, hours, mins;
 	char duration[sizeof("(%u+02:02)") + sizeof(int)*3];
@@ -104,7 +108,7 @@ static void show_entry(struct utmp *ut, int state, time_t dur_secs)
 		duration_str);
 }
 
-static int get_ut_type(struct utmp *ut)
+static int get_ut_type(struct utmpx *ut)
 {
 	if (ut->ut_line[0] == '~') {
 		if (strcmp(ut->ut_user, "shutdown") == 0) {
@@ -142,7 +146,7 @@ static int get_ut_type(struct utmp *ut)
 	return ut->ut_type;
 }
 
-static int is_runlevel_shutdown(struct utmp *ut)
+static int is_runlevel_shutdown(struct utmpx *ut)
 {
 	if (((ut->ut_pid & 255) == '0') || ((ut->ut_pid & 255) == '6')) {
 		return 1;
@@ -154,7 +158,7 @@ static int is_runlevel_shutdown(struct utmp *ut)
 int last_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int last_main(int argc UNUSED_PARAM, char **argv)
 {
-	struct utmp ut;
+	struct utmpx ut;
 	const char *filename = _PATH_WTMP;
 	llist_t *zlist;
 	off_t pos;
@@ -242,9 +246,9 @@ int last_main(int argc UNUSED_PARAM, char **argv)
 			{
 				llist_t *el, *next;
 				for (el = zlist; el; el = next) {
-					struct utmp *up = (struct utmp *)el->data;
+					struct utmpx *up = (struct utmpx *)el->data;
 					next = el->link;
-					if (strncmp(up->ut_line, ut.ut_line, UT_LINESIZE) == 0) {
+					if (strncmp(up->ut_line, ut.ut_line, __UT_LINESIZE) == 0) {
 						if (show) {
 							show_entry(&ut, NORMAL, up->ut_tv.tv_sec);
 							show = 0;
diff --git a/miscutils/runlevel.c b/miscutils/runlevel.c
index 76231df..8558db8 100644
--- a/miscutils/runlevel.c
+++ b/miscutils/runlevel.c
@@ -29,19 +29,19 @@
 int runlevel_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int runlevel_main(int argc UNUSED_PARAM, char **argv)
 {
-	struct utmp *ut;
+	struct utmpx *ut;
 	char prev;
 
-	if (argv[1]) utmpname(argv[1]);
+	if (argv[1]) utmpxname(argv[1]);
 
-	setutent();
-	while ((ut = getutent()) != NULL) {
+	setutxent();
+	while ((ut = getutxent()) != NULL) {
 		if (ut->ut_type == RUN_LVL) {
 			prev = ut->ut_pid / 256;
 			if (prev == 0) prev = 'N';
 			printf("%c %c\n", prev, ut->ut_pid % 256);
 			if (ENABLE_FEATURE_CLEAN_UP)
-				endutent();
+				endutxent();
 			return 0;
 		}
 	}
@@ -49,6 +49,6 @@ int runlevel_main(int argc UNUSED_PARAM, char **argv)
 	puts("unknown");
 
 	if (ENABLE_FEATURE_CLEAN_UP)
-		endutent();
+		endutxent();
 	return 1;
 }
diff --git a/miscutils/wall.c b/miscutils/wall.c
index bb709ee..50658f4 100644
--- a/miscutils/wall.c
+++ b/miscutils/wall.c
@@ -32,7 +32,7 @@
 int wall_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int wall_main(int argc UNUSED_PARAM, char **argv)
 {
-	struct utmp *ut;
+	struct utmpx *ut;
 	char *msg;
 	int fd;
 
@@ -46,8 +46,8 @@ int wall_main(int argc UNUSED_PARAM, char **argv)
 	msg = xmalloc_read(fd, NULL);
 	if (ENABLE_FEATURE_CLEAN_UP && argv[1])
 		close(fd);
-	setutent();
-	while ((ut = getutent()) != NULL) {
+	setutxent();
+	while ((ut = getutxent()) != NULL) {
 		char *line;
 		if (ut->ut_type != USER_PROCESS)
 			continue;
@@ -56,7 +56,7 @@ int wall_main(int argc UNUSED_PARAM, char **argv)
 		free(line);
 	}
 	if (ENABLE_FEATURE_CLEAN_UP) {
-		endutent();
+		endutxent();
 		free(msg);
 	}
 	return EXIT_SUCCESS;
diff --git a/procps/uptime.c b/procps/uptime.c
index 778812a..149bae6 100644
--- a/procps/uptime.c
+++ b/procps/uptime.c
@@ -81,10 +81,10 @@ int uptime_main(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
 
 #if ENABLE_FEATURE_UPTIME_UTMP_SUPPORT
 	{
-		struct utmp *ut;
+		struct utmpx *ut;
 		unsigned users = 0;
-		while ((ut = getutent()) != NULL) {
-			if ((ut->ut_type == USER_PROCESS) && (ut->ut_name[0] != '\0'))
+		while ((ut = getutxent()) != NULL) {
+			if ((ut->ut_type == USER_PROCESS) && (ut->ut_user[0] != '\0'))
 				users++;
 		}
 		printf(",  %u users", users);