diff options
| -rw-r--r-- | Makefile-man.am | 12 | ||||
| -rw-r--r-- | man/sd-journal.xml | 4 | ||||
| -rw-r--r-- | man/sd_journal_enumerate_fields.xml | 161 | ||||
| -rw-r--r-- | man/sd_journal_query_unique.xml | 44 | ||||
| -rw-r--r-- | src/journal/journal-internal.h | 21 | ||||
| -rw-r--r-- | src/journal/sd-journal.c | 156 | ||||
| -rw-r--r-- | src/libsystemd/libsystemd.sym | 6 | ||||
| -rw-r--r-- | src/systemd/sd-journal.h | 13 |
8 files changed, 390 insertions, 27 deletions
diff --git a/Makefile-man.am b/Makefile-man.am index 12900daa96..28b5fb6adb 100644 --- a/Makefile-man.am +++ b/Makefile-man.am @@ -72,6 +72,7 @@ MANPAGES += \ man/sd_id128_to_string.3 \ man/sd_is_fifo.3 \ man/sd_journal_add_match.3 \ + man/sd_journal_enumerate_fields.3 \ man/sd_journal_get_catalog.3 \ man/sd_journal_get_cursor.3 \ man/sd_journal_get_cutoff_realtime_usec.3 \ @@ -237,6 +238,7 @@ MANPAGES_ALIAS += \ man/SD_JOURNAL_FOREACH.3 \ man/SD_JOURNAL_FOREACH_BACKWARDS.3 \ man/SD_JOURNAL_FOREACH_DATA.3 \ + man/SD_JOURNAL_FOREACH_FIELD.3 \ man/SD_JOURNAL_FOREACH_UNIQUE.3 \ man/SD_JOURNAL_INVALIDATE.3 \ man/SD_JOURNAL_LOCAL_ONLY.3 \ @@ -397,6 +399,7 @@ MANPAGES_ALIAS += \ man/sd_journal_process.3 \ man/sd_journal_reliable_fd.3 \ man/sd_journal_restart_data.3 \ + man/sd_journal_restart_fields.3 \ man/sd_journal_restart_unique.3 \ man/sd_journal_seek_cursor.3 \ man/sd_journal_seek_monotonic_usec.3 \ @@ -565,6 +568,7 @@ man/SD_JOURNAL_CURRENT_USER.3: man/sd_journal_open.3 man/SD_JOURNAL_FOREACH.3: man/sd_journal_next.3 man/SD_JOURNAL_FOREACH_BACKWARDS.3: man/sd_journal_next.3 man/SD_JOURNAL_FOREACH_DATA.3: man/sd_journal_get_data.3 +man/SD_JOURNAL_FOREACH_FIELD.3: man/sd_journal_enumerate_fields.3 man/SD_JOURNAL_FOREACH_UNIQUE.3: man/sd_journal_query_unique.3 man/SD_JOURNAL_INVALIDATE.3: man/sd_journal_get_fd.3 man/SD_JOURNAL_LOCAL_ONLY.3: man/sd_journal_open.3 @@ -725,6 +729,7 @@ man/sd_journal_printv.3: man/sd_journal_print.3 man/sd_journal_process.3: man/sd_journal_get_fd.3 man/sd_journal_reliable_fd.3: man/sd_journal_get_fd.3 man/sd_journal_restart_data.3: man/sd_journal_get_data.3 +man/sd_journal_restart_fields.3: man/sd_journal_enumerate_fields.3 man/sd_journal_restart_unique.3: man/sd_journal_query_unique.3 man/sd_journal_seek_cursor.3: man/sd_journal_seek_head.3 man/sd_journal_seek_monotonic_usec.3: man/sd_journal_seek_head.3 @@ -1017,6 +1022,9 @@ man/SD_JOURNAL_FOREACH_BACKWARDS.html: man/sd_journal_next.html man/SD_JOURNAL_FOREACH_DATA.html: man/sd_journal_get_data.html $(html-alias) +man/SD_JOURNAL_FOREACH_FIELD.html: man/sd_journal_enumerate_fields.html + $(html-alias) + man/SD_JOURNAL_FOREACH_UNIQUE.html: man/sd_journal_query_unique.html $(html-alias) @@ -1497,6 +1505,9 @@ man/sd_journal_reliable_fd.html: man/sd_journal_get_fd.html man/sd_journal_restart_data.html: man/sd_journal_get_data.html $(html-alias) +man/sd_journal_restart_fields.html: man/sd_journal_enumerate_fields.html + $(html-alias) + man/sd_journal_restart_unique.html: man/sd_journal_query_unique.html $(html-alias) @@ -2534,6 +2545,7 @@ EXTRA_DIST += \ man/sd_id128_to_string.xml \ man/sd_is_fifo.xml \ man/sd_journal_add_match.xml \ + man/sd_journal_enumerate_fields.xml \ man/sd_journal_get_catalog.xml \ man/sd_journal_get_cursor.xml \ man/sd_journal_get_cutoff_realtime_usec.xml \ diff --git a/man/sd-journal.xml b/man/sd-journal.xml index a1185d372b..09747a480c 100644 --- a/man/sd-journal.xml +++ b/man/sd-journal.xml @@ -77,6 +77,8 @@ <citerefentry><refentrytitle>sd_journal_get_realtime_usec</refentrytitle><manvolnum>3</manvolnum></citerefentry>, <citerefentry><refentrytitle>sd_journal_add_match</refentrytitle><manvolnum>3</manvolnum></citerefentry>, <citerefentry><refentrytitle>sd_journal_seek_head</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_journal_query_enumerate</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_journal_enumerate_fields</refentrytitle><manvolnum>3</manvolnum></citerefentry>, <citerefentry><refentrytitle>sd_journal_get_cursor</refentrytitle><manvolnum>3</manvolnum></citerefentry>, <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>, @@ -111,6 +113,8 @@ <citerefentry><refentrytitle>sd_journal_get_realtime_usec</refentrytitle><manvolnum>3</manvolnum></citerefentry>, <citerefentry><refentrytitle>sd_journal_add_match</refentrytitle><manvolnum>3</manvolnum></citerefentry>, <citerefentry><refentrytitle>sd_journal_seek_head</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_journal_query_enumerate</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_journal_enumerate_fields</refentrytitle><manvolnum>3</manvolnum></citerefentry>, <citerefentry><refentrytitle>sd_journal_get_cursor</refentrytitle><manvolnum>3</manvolnum></citerefentry>, <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>, diff --git a/man/sd_journal_enumerate_fields.xml b/man/sd_journal_enumerate_fields.xml new file mode 100644 index 0000000000..fa5884106b --- /dev/null +++ b/man/sd_journal_enumerate_fields.xml @@ -0,0 +1,161 @@ +<?xml version='1.0'?> <!--*-nxml-*--> +<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" + "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> + +<!-- + This file is part of systemd. + + Copyright 2016 Lennart Poettering + + 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_enumerate_fields"> + + <refentryinfo> + <title>sd_journal_enumerate_fields</title> + <productname>systemd</productname> + + <authorgroup> + <author> + <contrib>Developer</contrib> + <firstname>Lennart</firstname> + <surname>Poettering</surname> + <email>lennart@poettering.net</email> + </author> + </authorgroup> + </refentryinfo> + + <refmeta> + <refentrytitle>sd_journal_enumerate_fields</refentrytitle> + <manvolnum>3</manvolnum> + </refmeta> + + <refnamediv> + <refname>sd_journal_enumerate_fields</refname> + <refname>sd_journal_restart_fields</refname> + <refname>SD_JOURNAL_FOREACH_FIELD</refname> + <refpurpose>Read used field names from the journal</refpurpose> + </refnamediv> + + <refsynopsisdiv> + <funcsynopsis> + <funcsynopsisinfo>#include <systemd/sd-journal.h></funcsynopsisinfo> + + <funcprototype> + <funcdef>int <function>sd_journal_enumerate_fields</function></funcdef> + <paramdef>sd_journal *<parameter>j</parameter></paramdef> + <paramdef>const char **<parameter>field</parameter></paramdef> + </funcprototype> + + <funcprototype> + <funcdef>void <function>sd_journal_restart_fields</function></funcdef> + <paramdef>sd_journal *<parameter>j</parameter></paramdef> + </funcprototype> + + <funcprototype> + <funcdef><function>SD_JOURNAL_FOREACH_FIELD</function></funcdef> + <paramdef>sd_journal *<parameter>j</parameter></paramdef> + <paramdef>const char *<parameter>field</parameter></paramdef> + </funcprototype> + + </funcsynopsis> + </refsynopsisdiv> + + <refsect1> + <title>Description</title> + + <para><function>sd_journal_enumerate_fields()</function> may be used to iterate through all field names used in the + opened journal files. On each invocation the next field name is returned. The order of the returned field names is + not defined. It takes two arguments: the journal context object, plus a pointer to a constant string pointer where + the field name is stored in. The returned data is in a read-only memory map and is only valid until the next + invocation of <function>sd_journal_enumerate_fields()</function>. Note that this call is subject to the data field + size threshold as controlled by <function>sd_journal_set_data_threshold()</function>.</para> + + <para><function>sd_journal_restart_fields()</function> resets the field name enumeration index to the beginning of + the list. The next invocation of <function>sd_journal_enumerate_fields()</function> will return the first field + name again.</para> + + <para>The <function>SD_JOURNAL_FOREACH_FIELD()</function> macro may be used as a handy wrapper around + <function>sd_journal_restart_fields()</function> and <function>sd_journal_enumerate_fields()</function>.</para> + + <para>These functions currently are not influenced by matches set with <function>sd_journal_add_match()</function> + but this might change in a later version of this software.</para> + + <para>To retrieve the possible values a specific field can take use + <citerefentry><refentrytitle>sd_journal_query_unique</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para> + </refsect1> + + <refsect1> + <title>Return Value</title> + + <para><function>sd_journal_enumerate_fields()</function> returns a + positive integer if the next field name has been read, 0 when no + more field names are known, or a negative errno-style error code. + <function>sd_journal_restart_fields()</function> returns + nothing.</para> + </refsect1> + + <refsect1> + <title>Notes</title> + + <para>The <function>sd_journal_enumerate_fields()</function> and <function>sd_journal_restart_fields()</function> + interfaces are available as a shared library, which can be compiled and linked to with the + <constant>libsystemd</constant> <citerefentry + project='die-net'><refentrytitle>pkg-config</refentrytitle><manvolnum>1</manvolnum></citerefentry> file.</para> + </refsect1> + + <refsect1> + <title>Examples</title> + + <para>Use the <function>SD_JOURNAL_FOREACH_FIELD</function> macro to iterate through all field names in use in the + current journal.</para> + + <programlisting>#include <stdio.h> +#include <string.h> +#include <systemd/sd-journal.h> + +int main(int argc, char *argv[]) { + sd_journal *j; + const char *field; + int r; + + r = sd_journal_open(&j, SD_JOURNAL_LOCAL_ONLY); + if (r < 0) { + fprintf(stderr, "Failed to open journal: %s\n", strerror(-r)); + return 1; + } + SD_JOURNAL_FOREACH_FIELD(j, field) + printf("%s\n", field); + sd_journal_close(j); + return 0; +}</programlisting> + + </refsect1> + + <refsect1> + <title>See Also</title> + + <para> + <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>, + <citerefentry><refentrytitle>systemd.journal-fields</refentrytitle><manvolnum>7</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd-journal</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_journal_open</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_journal_query_unique</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_journal_get_data</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_journal_add_match</refentrytitle><manvolnum>3</manvolnum></citerefentry> + </para> + </refsect1> + +</refentry> diff --git a/man/sd_journal_query_unique.xml b/man/sd_journal_query_unique.xml index ac0e5f633f..dbff55c105 100644 --- a/man/sd_journal_query_unique.xml +++ b/man/sd_journal_query_unique.xml @@ -128,6 +128,11 @@ <para>Note that these functions currently are not influenced by matches set with <function>sd_journal_add_match()</function> but this might change in a later version of this software.</para> + + <para>To enumerate all field names currently in use (and thus all suitable field parameters for + <function>sd_journal_query_unique()</function>), use the + <citerefentry><refentrytitle>sd_journal_enumerate_fields</refentrytitle><manvolnum>3</manvolnum></citerefentry> + call.</para> </refsect1> <refsect1> @@ -167,25 +172,25 @@ #include <systemd/sd-journal.h> int main(int argc, char *argv[]) { - sd_journal *j; - const void *d; - size_t l; - int r; - - r = sd_journal_open(&j, SD_JOURNAL_LOCAL_ONLY); - if (r < 0) { - fprintf(stderr, "Failed to open journal: %s\n", strerror(-r)); - return 1; - } - r = sd_journal_query_unique(j, "_SYSTEMD_UNIT"); - if (r < 0) { - fprintf(stderr, "Failed to query journal: %s\n", strerror(-r)); - return 1; - } - SD_JOURNAL_FOREACH_UNIQUE(j, d, l) - printf("%.*s\n", (int) l, (const char*) d); - sd_journal_close(j); - return 0; + sd_journal *j; + const void *d; + size_t l; + int r; + + r = sd_journal_open(&j, SD_JOURNAL_LOCAL_ONLY); + if (r < 0) { + fprintf(stderr, "Failed to open journal: %s\n", strerror(-r)); + return 1; + } + r = sd_journal_query_unique(j, "_SYSTEMD_UNIT"); + if (r < 0) { + fprintf(stderr, "Failed to query journal: %s\n", strerror(-r)); + return 1; + } + SD_JOURNAL_FOREACH_UNIQUE(j, d, l) + printf("%.*s\n", (int) l, (const char*) d); + sd_journal_close(j); + return 0; }</programlisting> </refsect1> @@ -198,6 +203,7 @@ int main(int argc, char *argv[]) { <citerefentry><refentrytitle>systemd.journal-fields</refentrytitle><manvolnum>7</manvolnum></citerefentry>, <citerefentry><refentrytitle>sd-journal</refentrytitle><manvolnum>3</manvolnum></citerefentry>, <citerefentry><refentrytitle>sd_journal_open</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_journal_enumerate_fields</refentrytitle><manvolnum>3</manvolnum></citerefentry>, <citerefentry><refentrytitle>sd_journal_get_data</refentrytitle><manvolnum>3</manvolnum></citerefentry>, <citerefentry><refentrytitle>sd_journal_add_match</refentrytitle><manvolnum>3</manvolnum></citerefentry> </para> diff --git a/src/journal/journal-internal.h b/src/journal/journal-internal.h index fa5ca11636..a55d1bcc47 100644 --- a/src/journal/journal-internal.h +++ b/src/journal/journal-internal.h @@ -103,18 +103,27 @@ struct sd_journal { unsigned current_invalidate_counter, last_invalidate_counter; usec_t last_process_usec; + /* Iterating through unique fields and their data values */ char *unique_field; JournalFile *unique_file; uint64_t unique_offset; + /* Iterating through known fields */ + JournalFile *fields_file; + uint64_t fields_offset; + uint64_t fields_hash_table_index; + char *fields_buffer; + size_t fields_buffer_allocated; + int flags; - bool on_network; - bool no_new_files; - bool unique_file_lost; /* File we were iterating over got - removed, and there were no more - files, so sd_j_enumerate_unique - will return a value equal to 0. */ + bool on_network:1; + bool no_new_files:1; + bool unique_file_lost:1; /* File we were iterating over got + removed, and there were no more + files, so sd_j_enumerate_unique + will return a value equal to 0. */ + bool fields_file_lost:1; bool has_runtime_files:1; bool has_persistent_files:1; diff --git a/src/journal/sd-journal.c b/src/journal/sd-journal.c index 74a5e262f8..85d9bbe04f 100644 --- a/src/journal/sd-journal.c +++ b/src/journal/sd-journal.c @@ -1338,6 +1338,13 @@ static void remove_file_real(sd_journal *j, JournalFile *f) { j->unique_file_lost = true; } + if (j->fields_file == f) { + j->fields_file = ordered_hashmap_next(j->files, j->fields_file->path); + j->fields_offset = 0; + if (!j->fields_file) + j->fields_file_lost = true; + } + journal_file_close(f); j->current_invalidate_counter ++; @@ -1806,6 +1813,7 @@ _public_ void sd_journal_close(sd_journal *j) { free(j->path); free(j->prefix); free(j->unique_field); + free(j->fields_buffer); free(j); } @@ -2552,6 +2560,154 @@ _public_ void sd_journal_restart_unique(sd_journal *j) { j->unique_file_lost = false; } +_public_ int sd_journal_enumerate_fields(sd_journal *j, const char **field) { + int r; + + assert_return(j, -EINVAL); + assert_return(!journal_pid_changed(j), -ECHILD); + assert_return(field, -EINVAL); + + if (!j->fields_file) { + if (j->fields_file_lost) + return 0; + + j->fields_file = ordered_hashmap_first(j->files); + if (!j->fields_file) + return 0; + + j->fields_hash_table_index = 0; + j->fields_offset = 0; + } + + for (;;) { + JournalFile *f, *of; + Iterator i; + uint64_t m; + Object *o; + size_t sz; + bool found; + + f = j->fields_file; + + if (j->fields_offset == 0) { + bool eof = false; + + /* We are not yet positioned at any field. Let's pick the first one */ + r = journal_file_map_field_hash_table(f); + if (r < 0) + return r; + + m = le64toh(f->header->field_hash_table_size) / sizeof(HashItem); + for (;;) { + if (j->fields_hash_table_index >= m) { + /* Reached the end of the hash table, go to the next file. */ + eof = true; + break; + } + + j->fields_offset = le64toh(f->field_hash_table[j->fields_hash_table_index].head_hash_offset); + + if (j->fields_offset != 0) + break; + + /* Empty hash table bucket, go to next one */ + j->fields_hash_table_index++; + } + + if (eof) { + /* Proceed with next file */ + j->fields_file = ordered_hashmap_next(j->files, f->path); + if (!j->fields_file) { + *field = NULL; + return 0; + } + + j->fields_offset = 0; + j->fields_hash_table_index = 0; + continue; + } + + } else { + /* We are already positioned at a field. If so, let's figure out the next field from it */ + + r = journal_file_move_to_object(f, OBJECT_FIELD, j->fields_offset, &o); + if (r < 0) + return r; + + j->fields_offset = le64toh(o->field.next_hash_offset); + if (j->fields_offset == 0) { + /* Reached the end of the hash table chain */ + j->fields_hash_table_index++; + continue; + } + } + + /* We use OBJECT_UNUSED here, so that the iteator below doesn't remove our mmap window */ + r = journal_file_move_to_object(f, OBJECT_UNUSED, j->fields_offset, &o); + if (r < 0) + return r; + + /* Because we used OBJECT_UNUSED above, we need to do our type check manually */ + if (o->object.type != OBJECT_FIELD) { + log_debug("%s:offset " OFSfmt ": object has type %i, expected %i", f->path, j->fields_offset, o->object.type, OBJECT_FIELD); + return -EBADMSG; + } + + sz = le64toh(o->object.size) - offsetof(Object, field.payload); + + /* Let's see if we already returned this field name before. */ + found = false; + ORDERED_HASHMAP_FOREACH(of, j->files, i) { + if (of == f) + break; + + /* Skip this file it didn't have any fields indexed */ + if (JOURNAL_HEADER_CONTAINS(of->header, n_fields) && le64toh(of->header->n_fields) <= 0) + continue; + + r = journal_file_find_field_object_with_hash(of, o->field.payload, sz, le64toh(o->field.hash), NULL, NULL); + if (r < 0) + return r; + if (r > 0) { + found = true; + break; + } + } + + if (found) + continue; + + /* Check if this is really a valid string containing no NUL byte */ + if (memchr(o->field.payload, 0, sz)) + return -EBADMSG; + + if (sz > j->data_threshold) + sz = j->data_threshold; + + if (!GREEDY_REALLOC(j->fields_buffer, j->fields_buffer_allocated, sz + 1)) + return -ENOMEM; + + memcpy(j->fields_buffer, o->field.payload, sz); + j->fields_buffer[sz] = 0; + + if (!field_is_valid(j->fields_buffer)) + return -EBADMSG; + + *field = j->fields_buffer; + return 1; + } +} + +_public_ void sd_journal_restart_fields(sd_journal *j) { + if (!j) + return; + + j->fields_file = NULL; + j->fields_hash_table_index = 0; + j->fields_offset = 0; + j->fields_file_lost = false; +} + _public_ int sd_journal_reliable_fd(sd_journal *j) { assert_return(j, -EINVAL); assert_return(!journal_pid_changed(j), -ECHILD); diff --git a/src/libsystemd/libsystemd.sym b/src/libsystemd/libsystemd.sym index 043ff13e6f..d6928bfbb7 100644 --- a/src/libsystemd/libsystemd.sym +++ b/src/libsystemd/libsystemd.sym @@ -481,3 +481,9 @@ global: sd_bus_path_encode_many; sd_listen_fds_with_names; } LIBSYSTEMD_226; + +LIBSYSTEMD_229 { +global: + sd_journal_enumerate_fields; + sd_journal_restart_fields; +} LIBSYSTEMD_227; diff --git a/src/systemd/sd-journal.h b/src/systemd/sd-journal.h index 7f16c69ce5..caf322f062 100644 --- a/src/systemd/sd-journal.h +++ b/src/systemd/sd-journal.h @@ -129,6 +129,9 @@ int sd_journal_query_unique(sd_journal *j, const char *field); int sd_journal_enumerate_unique(sd_journal *j, const void **data, size_t *l); void sd_journal_restart_unique(sd_journal *j); +int sd_journal_enumerate_fields(sd_journal *j, const char **field); +void sd_journal_restart_fields(sd_journal *j); + int sd_journal_get_fd(sd_journal *j); int sd_journal_get_events(sd_journal *j); int sd_journal_get_timeout(sd_journal *j, uint64_t *timeout_usec); @@ -142,22 +145,28 @@ 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 */ +/* The inverse condition avoids ambiguity of dangling 'else' after the macro */ #define SD_JOURNAL_FOREACH(j) \ if (sd_journal_seek_head(j) < 0) { } \ else while (sd_journal_next(j) > 0) -/* the inverse condition avoids ambiguity of danling 'else' after the macro */ +/* The inverse condition avoids ambiguity of dangling 'else' after the macro */ #define SD_JOURNAL_FOREACH_BACKWARDS(j) \ if (sd_journal_seek_tail(j) < 0) { } \ else while (sd_journal_previous(j) > 0) +/* Iterate through the data fields of the current journal entry */ #define SD_JOURNAL_FOREACH_DATA(j, data, l) \ for (sd_journal_restart_data(j); sd_journal_enumerate_data((j), &(data), &(l)) > 0; ) +/* Iterate through the all known values of a specific field */ #define SD_JOURNAL_FOREACH_UNIQUE(j, data, l) \ for (sd_journal_restart_unique(j); sd_journal_enumerate_unique((j), &(data), &(l)) > 0; ) +/* Iterate through all known field names */ +#define SD_JOURNAL_FOREACH_FIELD(j, field) \ + for (sd_journal_restart_fields(j); sd_journal_enumerate_fields((j), &(field)) > 0; ) + _SD_DEFINE_POINTER_CLEANUP_FUNC(sd_journal, sd_journal_close); _SD_END_DECLARATIONS; |