log: Drop newlines in the middle of the perror()-like messages

Calling vlogmsg() twice from logmsg_perror() results in this beauty:

  $ ./pasta -i foo
  Invalid interface name foo
  : No such device

because the first part of the message, corresponding to the first
call, doesn't end with a newline, and vlogmsg() adds it.

Given that we can't easily append an argument (error description) to
a variadic list, add a 'newline' parameter to all the functions that
currently add a newline if missing, and disable that on the first call
to vlogmsg() from logmsg_perror(). Not very pretty but I can't think
of any solution that's less messy than this.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>

1 files changed, 9 insertions, 9 deletions

diff --git a/log.h b/log.h
index 6f34e8d..51ddafa 100644
--- a/log.h
+++ b/log.h
@@ -13,16 +13,16 @@
 #define LOGFILE_CUT_RATIO		30	/* When full, cut ~30% size */
 #define LOGFILE_SIZE_MIN		(5UL * MAX(BUFSIZ, PAGE_SIZE))
 
-void vlogmsg(int pri, const char *format, va_list ap);
-void logmsg(int pri, const char *format, ...)
-	__attribute__((format(printf, 2, 3)));
+void vlogmsg(bool newline, int pri, const char *format, va_list ap);
+void logmsg(bool newline, int pri, const char *format, ...)
+	__attribute__((format(printf, 3, 4)));
 void logmsg_perror(int pri, const char *format, ...)
 	__attribute__((format(printf, 2, 3)));
 
-#define err(...)		logmsg(		LOG_ERR,	__VA_ARGS__)
-#define warn(...)		logmsg(		LOG_WARNING,	__VA_ARGS__)
-#define info(...)		logmsg(		LOG_INFO,	__VA_ARGS__)
-#define debug(...)		logmsg(		LOG_DEBUG,	__VA_ARGS__)
+#define err(...)		logmsg(true,	LOG_ERR,	__VA_ARGS__)
+#define warn(...)		logmsg(true,	LOG_WARNING,	__VA_ARGS__)
+#define info(...)		logmsg(true,	LOG_INFO,	__VA_ARGS__)
+#define debug(...)		logmsg(true,	LOG_DEBUG,	__VA_ARGS__)
 
 #define err_perror(...)		logmsg_perror(	LOG_ERR,	__VA_ARGS__)
 #define warn_perror(...)	logmsg_perror(	LOG_WARNING,	__VA_ARGS__)
@@ -54,8 +54,8 @@ void trace_init(int enable);
 
 void __openlog(const char *ident, int option, int facility);
 void logfile_init(const char *name, const char *path, size_t size);
-void passt_vsyslog(int pri, const char *format, va_list ap);
-void logfile_write(int pri, const char *format, va_list ap);
+void passt_vsyslog(bool newline, int pri, const char *format, va_list ap);
+void logfile_write(bool newline, int pri, const char *format, va_list ap);
 void __setlogmask(int mask);
 
 #endif /* LOG_H */