From 5ec508cc5c13d831c93ce98d84b1d9cedb0117a7 Mon Sep 17 00:00:00 2001

From: Jan Synacek <jsynacek@redhat.com>

Date: Mon, 1 Feb 2016 09:23:58 +0100

Subject: [PATCH] sd-journal: introduce has_runtime_files and

 has_persistent_files

Also introduce sd_journal_has_runtime_files() and

sd_journal_has_persistent_files() to the public API. These functions

can be used to easily find out if the open journal files are runtime

and/or persistent.

Cherry-picked from: 39fd5b08a73f144a20202a665bd25cad51d8a90b

Resolves: #1082179

---

 Makefile-man.am                      |  7 ++

 man/sd-journal.xml                   |  8 ++-

 man/sd_journal_has_runtime_files.xml | 95 ++++++++++++++++++++++++++++

 src/journal/journal-internal.h       |  2 +

 src/journal/sd-journal.c             | 29 ++++++---

 src/systemd/sd-journal.h             |  3 +

 6 files changed, 133 insertions(+), 11 deletions(-)

 create mode 100644 man/sd_journal_has_runtime_files.xml

diff --git a/Makefile-man.am b/Makefile-man.am

index 497be6612c..7ec709c8b8 100644

--- a/Makefile-man.am

+++ b/Makefile-man.am

@@ -40,6 +40,7 @@ MANPAGES += \

 	man/sd_journal_get_fd.3 \

 	man/sd_journal_get_realtime_usec.3 \

 	man/sd_journal_get_usage.3 \

+	man/sd_journal_has_runtime_files.3 \

 	man/sd_journal_next.3 \

 	man/sd_journal_open.3 \

 	man/sd_journal_print.3 \

@@ -176,6 +177,7 @@ MANPAGES_ALIAS += \

 	man/sd_journal_get_events.3 \

 	man/sd_journal_get_monotonic_usec.3 \

 	man/sd_journal_get_timeout.3 \

+	man/sd_journal_has_persistent_files.3 \

 	man/sd_journal_next_skip.3 \

 	man/sd_journal_open_container.3 \

 	man/sd_journal_open_directory.3 \

@@ -287,6 +289,7 @@ man/sd_journal_get_data_threshold.3: man/sd_journal_get_data.3

 man/sd_journal_get_events.3: man/sd_journal_get_fd.3

 man/sd_journal_get_monotonic_usec.3: man/sd_journal_get_realtime_usec.3

 man/sd_journal_get_timeout.3: man/sd_journal_get_fd.3

+man/sd_journal_has_persistent_files.3: man/sd_journal_has_runtime_files.3

 man/sd_journal_next_skip.3: man/sd_journal_next.3

 man/sd_journal_open_container.3: man/sd_journal_open.3

 man/sd_journal_open_directory.3: man/sd_journal_open.3

@@ -500,6 +503,9 @@ man/sd_journal_get_monotonic_usec.html: man/sd_journal_get_realtime_usec.html

 man/sd_journal_get_timeout.html: man/sd_journal_get_fd.html

 	$(html-alias)

+man/sd_journal_has_persistent_files.html: man/sd_journal_has_runtime_files.html

+	$(html-alias)

+

 man/sd_journal_next_skip.html: man/sd_journal_next.html

 	$(html-alias)

@@ -1727,6 +1733,7 @@ EXTRA_DIST += \

 	man/sd_journal_get_fd.xml \

 	man/sd_journal_get_realtime_usec.xml \

 	man/sd_journal_get_usage.xml \

+	man/sd_journal_has_runtime_files.xml \

 	man/sd_journal_next.xml \

 	man/sd_journal_open.xml \

 	man/sd_journal_print.xml \

diff --git a/man/sd-journal.xml b/man/sd-journal.xml

index 9b1a52207f..a1185d372b 100644

--- a/man/sd-journal.xml

+++ b/man/sd-journal.xml

@@ -81,9 +81,11 @@

     <citerefentry><refentrytitle>sd_journal_get_cutoff_realtime_usec</refentrytitle><manvolnum>3</manvolnum></citerefentry>,

     <citerefentry><refentrytitle>sd_journal_get_cutoff_monotonic_usec</refentrytitle><manvolnum>3</manvolnum></citerefentry>,

     <citerefentry><refentrytitle>sd_journal_get_usage</refentrytitle><manvolnum>3</manvolnum></citerefentry>,

-    <citerefentry><refentrytitle>sd_journal_get_catalog</refentrytitle><manvolnum>3</manvolnum></citerefentry>

+    <citerefentry><refentrytitle>sd_journal_get_catalog</refentrytitle><manvolnum>3</manvolnum></citerefentry>,

+    <citerefentry><refentrytitle>sd_journal_get_fd</refentrytitle><manvolnum>3</manvolnum></citerefentry>,

+    <citerefentry><refentrytitle>sd_journal_has_runtime_files</refentrytitle><manvolnum>3</manvolnum></citerefentry>

     and

-    <citerefentry><refentrytitle>sd_journal_get_fd</refentrytitle><manvolnum>3</manvolnum></citerefentry>

+    <citerefentry><refentrytitle>sd_journal_has_persistent_files</refentrytitle><manvolnum>3</manvolnum></citerefentry>

     for more information about the functions implemented.</para>

     <para>Command line access for submitting entries to the journal is

@@ -116,6 +118,8 @@

       <citerefentry><refentrytitle>sd_journal_get_fd</refentrytitle><manvolnum>3</manvolnum></citerefentry>,

       <citerefentry><refentrytitle>sd_journal_query_unique</refentrytitle><manvolnum>3</manvolnum></citerefentry>,

       <citerefentry><refentrytitle>sd_journal_get_catalog</refentrytitle><manvolnum>3</manvolnum></citerefentry>,

+      <citerefentry><refentrytitle>sd_journal_has_runtime_files</refentrytitle><manvolnum>3</manvolnum></citerefentry>,

+      <citerefentry><refentrytitle>sd_journal_has_persistent_files</refentrytitle><manvolnum>3</manvolnum></citerefentry>,

       <citerefentry><refentrytitle>journalctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,

       <citerefentry><refentrytitle>sd-id128</refentrytitle><manvolnum>3</manvolnum></citerefentry>,

       <citerefentry project='die-net'><refentrytitle>pkg-config</refentrytitle><manvolnum>1</manvolnum></citerefentry>

diff --git a/man/sd_journal_has_runtime_files.xml b/man/sd_journal_has_runtime_files.xml

new file mode 100644

index 0000000000..237e649206

--- /dev/null

+++ b/man/sd_journal_has_runtime_files.xml

@@ -0,0 +1,95 @@

+ 

+

+  "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">

+

+

+  This file is part of systemd.

+

+  Copyright 2016 Jan Synáček

+

+  systemd is free software; you can redistribute it and/or modify it

+  under the terms of the GNU Lesser General Public License as published by

+  the Free Software Foundation; either version 2.1 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

+  Lesser General Public License for more details.

+

+  You should have received a copy of the GNU Lesser General Public License

+  along with systemd; If not, see <http://www.gnu.org/licenses/>.

+-->

+

+<refentry id="sd_journal_has_runtime_files">

+

+  <refentryinfo>

+    <title>sd_journal_has_runtime_files</title>

+    <productname>systemd</productname>

+

+    <authorgroup>

+      <author>

+        <contrib>Developer</contrib>

+        <firstname>Jan</firstname>

+        <surname>Synáček</surname>

+        <email>jan.synacek@gmail.com</email>

+      </author>

+    </authorgroup>

+  </refentryinfo>

+

+  <refmeta>

+    <refentrytitle>sd_journal_has_runtime_files</refentrytitle>

+    <manvolnum>3</manvolnum>

+  </refmeta>

+

+  <refnamediv>

+    <refname>sd_journal_has_runtime_files</refname>

+    <refname>sd_journal_has_persistent_files</refname>

+    <refpurpose>Query availability of runtime or persistent journal files.</refpurpose>

+  </refnamediv>

+

+  <refsynopsisdiv>

+    <funcsynopsis>

+      <funcsynopsisinfo>#include <systemd/sd-journal.h></funcsynopsisinfo>

+

+      <funcprototype>

+        <funcdef>int <function>sd_journal_has_runtime_files</function></funcdef>

+        <paramdef>sd_journal *<parameter>j</parameter></paramdef>

+      </funcprototype>

+

+      <funcprototype>

+        <funcdef>int <function>sd_journal_has_persistent_files</function></funcdef>

+        <paramdef>sd_journal *<parameter>j</parameter></paramdef>

+      </funcprototype>

+

+    </funcsynopsis>

+  </refsynopsisdiv>

+

+  <refsect1>

+    <title>Description</title>

+

+    <para><function>sd_journal_has_runtime_files()</function> returns a positive value

+    if runtime journal files (present in /run/systemd/journal/) have been found.

+    Otherwise returns 0.</para>

+

+    <para><function>sd_journal_has_persistent_files()</function> returns a positive value

+    if persistent journal files (present in /var/log/journal/) have been found.

+    Otherwise returns 0.</para>

+  </refsect1>

+

+  <refsect1>

+    <title>Return value</title>

+    <para>Both <function>sd_journal_has_runtime_files()</function>

+    and <function>sd_journal_has_persistent_files()</function> return -EINVAL

+    if their argument is NULL.

+    </para>

+  </refsect1>

+

+  <refsect1>

+    <title>See Also</title>

+    <para>

+      <citerefentry><refentrytitle>sd-journal</refentrytitle><manvolnum>3</manvolnum></citerefentry>

+    </para>

+  </refsect1>

+

+</refentry>

diff --git a/src/journal/journal-internal.h b/src/journal/journal-internal.h

index b51ecdb600..115d7776da 100644

--- a/src/journal/journal-internal.h

+++ b/src/journal/journal-internal.h

@@ -115,6 +115,8 @@ struct sd_journal {

                                   removed, and there were no more

                                   files, so sd_j_enumerate_unique

                                   will return a value equal to 0. */

+        bool has_runtime_files:1;

+        bool has_persistent_files:1;

         size_t data_threshold;

diff --git a/src/journal/sd-journal.c b/src/journal/sd-journal.c

index 9b9e8ac859..20456c3a12 100644

--- a/src/journal/sd-journal.c

+++ b/src/journal/sd-journal.c

@@ -1230,8 +1230,7 @@ static int add_any_file(sd_journal *j, const char *path) {

 }

 static int add_file(sd_journal *j, const char *prefix, const char *filename) {

-        _cleanup_free_ char *path = NULL;

-        int r;

+        char *path = NULL;

         assert(j);

         assert(prefix);

@@ -1241,14 +1240,14 @@ static int add_file(sd_journal *j, const char *prefix, const char *filename) {

             !file_type_wanted(j->flags, filename))

                 return 0;

-        path = strjoin(prefix, "/", filename, NULL);

-        if (!path)

-                return -ENOMEM;

+        path = strjoina(prefix, "/", filename);

-        r = add_any_file(j, path);

-        if (r == -ENOENT)

-                return 0;

-        return r;

+        if (!j->has_runtime_files && path_startswith(path, "/run/log/journal"))

+                j->has_runtime_files = true;

+        else if (!j->has_persistent_files && path_startswith(path, "/var/log/journal"))

+                j->has_persistent_files = true;

+

+        return add_any_file(j, path);

 }

 static int remove_file(sd_journal *j, const char *prefix, const char *filename) {

@@ -2616,3 +2615,15 @@ _public_ int sd_journal_get_data_threshold(sd_journal *j, size_t *sz) {

         *sz = j->data_threshold;

         return 0;

 }

+

+_public_ int sd_journal_has_runtime_files(sd_journal *j) {

+        assert_return(j, -EINVAL);

+

+        return j->has_runtime_files;

+}

+

+_public_ int sd_journal_has_persistent_files(sd_journal *j) {

+        assert_return(j, -EINVAL);

+

+        return j->has_persistent_files;

+}

diff --git a/src/systemd/sd-journal.h b/src/systemd/sd-journal.h

index 00237a2158..d5fd46eea4 100644

--- a/src/systemd/sd-journal.h

+++ b/src/systemd/sd-journal.h

@@ -138,6 +138,9 @@ int sd_journal_reliable_fd(sd_journal *j);

 int sd_journal_get_catalog(sd_journal *j, char **text);

 int sd_journal_get_catalog_for_message_id(sd_id128_t id, char **text);

+int sd_journal_has_runtime_files(sd_journal *j);

+int sd_journal_has_persistent_files(sd_journal *j);

+

 /* the inverse condition avoids ambiguity of danling 'else' after the macro */

 #define SD_JOURNAL_FOREACH(j)                                           \

         if (sd_journal_seek_head(j) < 0) { }                            \