Refactor, move logit() and log macros to log.c + log.h

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

src/log.h

@@ -0,0 +1,48 @@
+/* Finit daemon log functions
+ *
+ * Copyright (c) 2008-2017  Joachim Nilsson <troglobit@gmail.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef FINIT_LOG_H_
+#define FINIT_LOG_H_
+
+#include <err.h>
+#include <string.h>		/* strerror() */
+#include <syslog.h>
+
+/*
+ * Error and debug messages
+ *
+ * Use of logit() is preferred, but these are guaranteed to display on
+ * /dev/console as well.  Useful for critical errors and early debug.
+ */
+#define   _l(prio, fmt, args...) do { if (_slup) warnx(fmt, ##args); logit(prio, fmt "\n", ##args); } while (0)
+#define   _m(prio, fmt, args...) do { _l(prio, "%s() - " fmt, __func__, ##args); } while (0)
+#define   _d(fmt, args...)  do { if (debug) { _m(LOG_DEBUG, fmt, ##args); } } while (0)
+#define   _w(fmt, args...)  do { _m(LOG_WARNING, fmt, ##args); } while (0)
+#define   _e(fmt, args...)  do { _m(LOG_ERR, fmt, ##args); } while (0)
+#define  _pe(fmt, args...)  do { _m(LOG_ERR, fmt ". Error %d: %s", ##args, errno, strerror(errno)); } while (0)
+
+extern int _slup;		/* INTERNAL: Is syslog up yet? */
+
+void    logit           (int prio, const char *fmt, ...);
+
+#endif /* FINIT_LOG_H_ */