From 8a71f2d3239bbe1aa957097d7696aed75c5160d1 Mon Sep 17 00:00:00 2001
From: Joachim Wiberg <troglobit@gmail.com>
Date: Sun, 14 Feb 2021 03:52:56 +0100
Subject: [PATCH] Workaround for _PATH_UTMP and _PATH_WTMP defines on musl libc

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>
---
 src/initctl.c  |  2 +-
 src/utmp-api.c |  6 +-----
 src/utmp-api.h | 18 ++++++++++++++++++
 3 files changed, 20 insertions(+), 6 deletions(-)

diff --git a/src/initctl.c b/src/initctl.c
index a9c5e70a..36d7e2af 100644
--- a/src/initctl.c
+++ b/src/initctl.c
@@ -31,7 +31,6 @@
 #include <signal.h>
 #include <stdio.h>
 #include <time.h>
-#include <utmp.h>
 #include <arpa/inet.h>
 #include <lite/lite.h>
 
@@ -40,6 +39,7 @@
 #include "serv.h"
 #include "service.h"
 #include "util.h"
+#include "utmp-api.h"
 
 #define _PATH_COND _PATH_VARRUN "finit/cond/"
 
diff --git a/src/utmp-api.c b/src/utmp-api.c
index c315f0eb..ab9a09d0 100644
--- a/src/utmp-api.c
+++ b/src/utmp-api.c
@@ -25,16 +25,12 @@
 
 #include <paths.h>
 #include <time.h>
-#include <utmp.h>
 #include <arpa/inet.h>
 #include <sys/utsname.h>
 #include <lite/lite.h>
 
 #include "helpers.h"
-
-#ifndef _PATH_BTMP
-#define _PATH_BTMP "/var/log/btmp"
-#endif
+#include "utmp-api.h"
 
 #define MAX_NO 5
 #define MAX_SZ 100 * 1024
diff --git a/src/utmp-api.h b/src/utmp-api.h
index 20f67cf7..1f81b6fb 100644
--- a/src/utmp-api.h
+++ b/src/utmp-api.h
@@ -24,6 +24,24 @@
 #ifndef FINIT_UTMP_API_H_
 #define FINIT_UTMP_API_H_
 
+#include <utmp.h>
+
+/*
+ * musl libc default to /dev/null/utmp and /dev/null/wtmp, respectively.
+ * See https://www.openwall.com/lists/musl/2012/03/04/4 for reasoning.
+ *
+ * Also, there's no __MUSL__, so we cannot make a libc-specific check
+ * here to work around this, that's why everyone pays.
+ */
+#undef _PATH_UTMP
+#undef _PATH_WTMP
+#undef _PATH_BTMP
+
+#define _PATH_UTMP "/var/run/wtmp"
+#define _PATH_WTMP "/var/log/wtmp"
+#define _PATH_BTMP "/var/log/btmp"
+
+
 int utmp_set         (int type, int pid, char *line, char *id, char *user);
 int utmp_set_boot    (void);
 int utmp_set_halt    (void);