From 84d70e63fc105e3713943ed8c0bdd4e31a698226 Mon Sep 17
00:00:00 2001 From: Joachim Nilsson <troglobit@gmail.com> Date: Thu, 16 Jan
2020 22:16:51 +0100 Subject: [PATCH] Drop libcompat to simplify build deps
and really fix

The original idea with libcompat was to keep as few objects as
possible for linking with libsyslog.  That in turn to prevent
a user of libsyslog from suddenly also getting strong binding
to symbols like strlcpy() from libsyslog, rather than their C
library of choice.

However, this caused strlcpy.c to be built as both .o and .lo
files, which in turn caused really bizarre build problems due
to bad DAG dependency.

This patch drops libcompat and instead marks all replacement APIs
as weak symbols, which a C library can override.

Signed-off-by: Joachim Nilsson <troglobit@gmail.com>

Upstream-Status: Backport
[https://github.com/troglobit/sysklogd/commit/84d70e63fc105e3713943ed8c0bdd4e31a698226]

Signed-off-by: Changqing Li <changqing.li@windriver.com>
---
 lib/pidfile.c   |  8 +++++++-
 lib/utimensat.c | 10 ++++++++--
 src/Makefile.am |  7 +------
 3 files changed, 16 insertions(+), 9 deletions(-)

diff --git a/lib/pidfile.c b/lib/pidfile.c
index 81f2315..25b1c04 100644
--- a/lib/pidfile.c
+++ b/lib/pidfile.c
@@ -31,6 +31,9 @@
  * POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include <config.h>
+#ifndef HAVE_PIDFILE
+
 #define _GNU_SOURCE		/* Needed with GLIBC to get asprintf() */
 #include <sys/stat.h>		/* utimensat() */
 #include <sys/time.h>		/* utimensat() on *BSD */
@@ -54,7 +57,7 @@ const  char *__pidfile_path = RUNSTATEDIR;
 const  char *__pidfile_name = NULL;
 
 int
-pidfile(const char *basename)
+__pidfile(const char *basename)
 {
 	int save_errno;
 	int atexit_already;
@@ -127,6 +130,9 @@ pidfile(const char *basename)
 	return (0);
 }
 
+weak_alias(__pidfile, pidfile);
+#endif /* HAVE_PIDFILE */
+
 static void
 pidfile_cleanup(void)
 {
diff --git a/lib/utimensat.c b/lib/utimensat.c
index edf7e10..b68ce0e 100644
--- a/lib/utimensat.c
+++ b/lib/utimensat.c
@@ -15,7 +15,8 @@
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
-#include "config.h"
+#include <config.h>
+#ifndef HAVE_UTIMENSAT
 
 #include <errno.h>
 #ifdef HAVE_FCNTL_H
@@ -23,7 +24,8 @@
 #endif
 #include <sys/time.h>		/* lutimes(), utimes(), utimensat() */
 
-int utimensat(int dirfd, const char *pathname, const struct timespec ts[2], int flags)
+int
+__utimensat(int dirfd, const char *pathname, const struct timespec ts[2], int flags)
 {
 	int ret = -1;
 	struct timeval tv[2];
@@ -45,3 +47,7 @@ int utimensat(int dirfd, const char *pathname, const struct timespec ts[2], int
 
 	return ret;
 }
+
+weak_alias(__utimensat, utimensat);
+
+#endif /* HAVE_UTIMENSAT */
diff --git a/src/Makefile.am b/src/Makefile.am
index 6e2a51c..1db88d3 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -19,7 +19,6 @@
 bin_PROGRAMS          =
 sbin_PROGRAMS         = syslogd
 lib_LTLIBRARIES       = libsyslog.la
-noinst_LTLIBRARIES    = libcompat.la
 
 if ENABLE_KLOGD
 sbin_PROGRAMS        += klogd
@@ -48,10 +47,6 @@ logger_CPPFLAGS       = $(AM_CPPFLAGS) -D_XOPEN_SOURCE=600
 logger_LDADD          = $(LIBS) $(LIBOBJS)
 logger_LDADD         += libsyslog.la
 
-# Convenience library for libsyslog instead of linking with $(LTLIBOBJS),
-# which would pull in pidfile() and other (strong) symbols as well.
-libcompat_la_SOURCES  = ../lib/strlcpy.c ../lib/strlcat.c
-
 pkgconfigdir          = $(libdir)/pkgconfig
 pkgincludedir         = $(includedir)/syslog
 pkgconfig_DATA        = libsyslog.pc
@@ -59,4 +54,4 @@ pkginclude_HEADERS    = syslog.h
 libsyslog_la_SOURCES  = syslog.c syslog.h compat.h
 libsyslog_la_CPPFLAGS = $(AM_CPPFLAGS) -D_XOPEN_SOURCE=600
 libsyslog_la_LDFLAGS  = $(AM_LDFLAGS) -version-info 0:0:0
-libsyslog_la_LIBADD   = libcompat.la
+libsyslog_la_LIBADD   = $(LTLIBOJBS)
-- 
2.7.4