util: move all to shared/ and split external dependencies in separate internal libraries

Before:
  $ ldd /lib/systemd/systemd-timestamp
  linux-vdso.so.1 =>  (0x00007fffb05ff000)
  libselinux.so.1 => /lib64/libselinux.so.1 (0x00007f90aac57000)
  libcap.so.2 => /lib64/libcap.so.2 (0x00007f90aaa53000)
  librt.so.1 => /lib64/librt.so.1 (0x00007f90aa84a000)
  libc.so.6 => /lib64/libc.so.6 (0x00007f90aa494000)
  /lib64/ld-linux-x86-64.so.2 (0x00007f90aae90000)
  libdl.so.2 => /lib64/libdl.so.2 (0x00007f90aa290000)
  libattr.so.1 => /lib64/libattr.so.1 (0x00007f90aa08a000)
  libpthread.so.0 => /lib64/libpthread.so.0 (0x00007f90a9e6e000)

After:
  $ ldd systemd-timestamp
  linux-vdso.so.1 =>  (0x00007fff3cbff000)
  libselinux.so.1 => /lib64/libselinux.so.1 (0x00007f5eaa1c3000)
  librt.so.1 => /lib64/librt.so.1 (0x00007f5ea9fbb000)
  libc.so.6 => /lib64/libc.so.6 (0x00007f5ea9c04000)
  /lib64/ld-linux-x86-64.so.2 (0x00007f5eaa3fc000)
  libdl.so.2 => /lib64/libdl.so.2 (0x00007f5ea9a00000)
  libpthread.so.0 => /lib64/libpthread.so.0 (0x00007f5ea97e4000)

1 files changed, 111 insertions, 0 deletions

diff --git a/src/shared/log.h b/src/shared/log.h
new file mode 100644
index 000000000..3283808ff
--- /dev/null
+++ b/src/shared/log.h
@@ -0,0 +1,111 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+#ifndef foologhfoo
+#define foologhfoo
+
+/***
+  This file is part of systemd.
+
+  Copyright 2010 Lennart Poettering
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <syslog.h>
+#include <stdbool.h>
+#include <stdarg.h>
+
+#include "macro.h"
+
+typedef enum LogTarget{
+        LOG_TARGET_CONSOLE,
+        LOG_TARGET_KMSG,
+        LOG_TARGET_JOURNAL,
+        LOG_TARGET_JOURNAL_OR_KMSG,
+        LOG_TARGET_SYSLOG,
+        LOG_TARGET_SYSLOG_OR_KMSG,
+        LOG_TARGET_AUTO, /* console if stderr is tty, JOURNAL_OR_KMSG otherwise */
+        LOG_TARGET_NULL,
+        _LOG_TARGET_MAX,
+        _LOG_TARGET_INVALID = -1
+}  LogTarget;
+
+void log_set_target(LogTarget target);
+void log_set_max_level(int level);
+void log_set_facility(int facility);
+
+int log_set_target_from_string(const char *e);
+int log_set_max_level_from_string(const char *e);
+
+void log_show_color(bool b);
+void log_show_location(bool b);
+
+int log_show_color_from_string(const char *e);
+int log_show_location_from_string(const char *e);
+
+LogTarget log_get_target(void);
+int log_get_max_level(void);
+
+int log_open(void);
+void log_close(void);
+void log_forget_fds(void);
+
+void log_close_syslog(void);
+void log_close_journal(void);
+void log_close_kmsg(void);
+void log_close_console(void);
+
+void log_parse_environment(void);
+
+int log_meta(
+        int level,
+        const char*file,
+        int line,
+        const char *func,
+        const char *format, ...) _printf_attr_(5,6);
+
+int log_metav(
+        int level,
+        const char*file,
+        int line,
+        const char *func,
+        const char *format,
+        va_list ap);
+
+_noreturn_ void log_assert_failed(const char *text, const char *file, int line, const char *func);
+_noreturn_ void log_assert_failed_unreachable(const char *text, const char *file, int line, const char *func);
+
+/* This modifies the buffer passed! */
+int log_dump_internal(
+        int level,
+        const char*file,
+        int line,
+        const char *func,
+        char *buffer);
+
+#define log_full(level, ...) log_meta(level,   __FILE__, __LINE__, __func__, __VA_ARGS__)
+
+#define log_debug(...)   log_meta(LOG_DEBUG,   __FILE__, __LINE__, __func__, __VA_ARGS__)
+#define log_info(...)    log_meta(LOG_INFO,    __FILE__, __LINE__, __func__, __VA_ARGS__)
+#define log_notice(...)  log_meta(LOG_NOTICE,  __FILE__, __LINE__, __func__, __VA_ARGS__)
+#define log_warning(...) log_meta(LOG_WARNING, __FILE__, __LINE__, __func__, __VA_ARGS__)
+#define log_error(...)   log_meta(LOG_ERR,     __FILE__, __LINE__, __func__, __VA_ARGS__)
+
+/* This modifies the buffer passed! */
+#define log_dump(level, buffer) log_dump_internal(level, __FILE__, __LINE__, __func__, buffer)
+
+const char *log_target_to_string(LogTarget target);
+LogTarget log_target_from_string(const char *s);
+
+#endif