journal: implement parallel file traversal

1 files changed, 284 insertions, 62 deletions

diff --git a/src/journal/sd-journal.c b/src/journal/sd-journal.c
index 9f5f1e858b..6f47520217 100644
--- a/src/journal/sd-journal.c
+++ b/src/journal/sd-journal.c
@@ -21,6 +21,7 @@
 
 #include <errno.h>
 #include <fcntl.h>
+#include <stddef.h>
 
 #include "sd-journal.h"
 #include "journal-def.h"
@@ -151,7 +152,8 @@ int sd_journal_next(sd_journal *j) {
 
         if (new_current) {
                 j->current_file = new_current;
-                f->current_offset = new_offset;
+                j->current_file->current_offset = new_offset;
+                j->current_file->current_field = 0;
                 return 1;
         }
 
@@ -193,59 +195,134 @@ int sd_journal_previous(sd_journal *j) {
 
         if (new_current) {
                 j->current_file = new_current;
-                f->current_offset = new_offset;
+                j->current_file->current_offset = new_offset;
+                j->current_file->current_field = 0;
                 return 1;
         }
 
         return 0;
 }
 
-int sd_journal_get_cursor(sd_journal *j, void **cursor, size_t *size) {
-        JournalCursor *c;
+int sd_journal_get_cursor(sd_journal *j, char **cursor) {
         Object *o;
         int r;
+        char bid[33], sid[33];
 
         assert(j);
         assert(cursor);
-        assert(size);
 
-        if (!j->current_file || !j->current_file->current_offset <= 0)
-                return 0;
+        if (!j->current_file || j->current_file->current_offset <= 0)
+                return -EADDRNOTAVAIL;
 
         r = journal_file_move_to_object(j->current_file, j->current_file->current_offset, OBJECT_ENTRY, &o);
         if (r < 0)
                 return r;
 
-        c = new0(JournalCursor, 1);
-        if (!c)
-                return -ENOMEM;
+        sd_id128_to_string(j->current_file->header->seqnum_id, sid);
+        sd_id128_to_string(o->entry.boot_id, bid);
 
-        c->version = 1;
-        c->seqnum = o->entry.seqnum;
-        c->seqnum_id = j->current_file->header->seqnum_id;
-        c->boot_id = o->entry.boot_id;
-        c->monotonic = o->entry.monotonic;
-        c->realtime = o->entry.realtime;
-        c->xor_hash = o->entry.xor_hash;
-
-        *cursor = c;
-        *size = sizeof(JournalCursor);
+        if (asprintf(cursor,
+                     "s=%s;i=%llx;b=%s;m=%llx;t=%llx;x=%llx;p=%s",
+                     sid, (unsigned long long) le64toh(o->entry.seqnum),
+                     bid, (unsigned long long) le64toh(o->entry.monotonic),
+                     (unsigned long long) le64toh(o->entry.realtime),
+                     (unsigned long long) le64toh(o->entry.xor_hash),
+                     file_name_from_path(j->current_file->path)) < 0)
+                return -ENOMEM;
 
         return 1;
 }
 
-int sd_journal_set_cursor(sd_journal *j, const void *cursor, size_t size) {
+int sd_journal_set_cursor(sd_journal *j, const char *cursor) {
         return -EINVAL;
 }
 
+static int add_file(sd_journal *j, const char *prefix, const char *dir, const char *filename) {
+        char *fn;
+        int r;
+        JournalFile *f;
+
+        assert(j);
+        assert(prefix);
+        assert(filename);
+
+        if (dir)
+                fn = join(prefix, "/", dir, "/", filename, NULL);
+        else
+                fn = join(prefix, "/", filename, NULL);
+
+        if (!fn)
+                return -ENOMEM;
+
+        r = journal_file_open(fn, O_RDONLY, 0, NULL, &f);
+        free(fn);
+
+        if (r < 0) {
+                if (errno == ENOENT)
+                        return 0;
+
+                return r;
+        }
+
+        r = hashmap_put(j->files, f->path, f);
+        if (r < 0) {
+                journal_file_close(f);
+                return r;
+        }
+
+        return 0;
+}
+
+static int add_directory(sd_journal *j, const char *prefix, const char *dir) {
+        char *fn;
+        int r;
+        DIR *d;
+
+        assert(j);
+        assert(prefix);
+        assert(dir);
+
+        fn = join(prefix, "/", dir, NULL);
+        if (!fn)
+                return -ENOMEM;
+
+        d = opendir(fn);
+        free(fn);
+
+        if (!d) {
+                if (errno == ENOENT)
+                        return 0;
+
+                return -errno;
+        }
+
+        for (;;) {
+                struct dirent buf, *de;
+
+                r = readdir_r(d, &buf, &de);
+                if (r != 0 || !de)
+                        break;
+
+                if (!dirent_is_file_with_suffix(de, ".journal"))
+                        continue;
+
+                r = add_file(j, prefix, dir, de->d_name);
+                if (r < 0)
+                        log_debug("Failed to add file %s/%s/%s: %s", prefix, dir, de->d_name, strerror(-r));
+        }
+
+        closedir(d);
+
+        return 0;
+}
+
 int sd_journal_open(sd_journal **ret) {
         sd_journal *j;
-        char *fn;
         const char *p;
-        int r = 0;
         const char search_paths[] =
                 "/run/log/journal\0"
                 "/var/log/journal\0";
+        int r;
 
         assert(ret);
 
@@ -254,64 +331,47 @@ int sd_journal_open(sd_journal **ret) {
                 return -ENOMEM;
 
         j->files = hashmap_new(string_hash_func, string_compare_func);
-        if (!j->files)
+        if (!j->files) {
+                r = -ENOMEM;
                 goto fail;
+        }
+
+        /* We ignore most errors here, since the idea is to only open
+         * what's actually accessible, and ignore the rest. */
 
         NULSTR_FOREACH(p, search_paths) {
                 DIR *d;
 
                 d = opendir(p);
                 if (!d) {
-                        if (errno != ENOENT && r == 0)
-                                r = -errno;
-
+                        if (errno != ENOENT)
+                                log_debug("Failed to open %s: %m", p);
                         continue;
                 }
 
                 for (;;) {
                         struct dirent buf, *de;
-                        int k;
-                        JournalFile *f;
-
-                        k = readdir_r(d, &buf, &de);
-                        if (k != 0) {
-                                if (r == 0)
-                                        r = -k;
-
-                                break;
-                        }
+                        sd_id128_t id;
 
-                        if (!de)
+                        r = readdir_r(d, &buf, &de);
+                        if (r != 0 || !de)
                                 break;
 
-                        if (!dirent_is_file_with_suffix(de, ".journal"))
-                                continue;
+                        if (dirent_is_file_with_suffix(de, ".journal")) {
+                                r = add_file(j, p, NULL, de->d_name);
+                                if (r < 0)
+                                        log_debug("Failed to add file %s/%s: %s", p, de->d_name, strerror(-r));
 
-                        fn = join(p, "/", de->d_name, NULL);
-                        if (!fn) {
-                                r = -ENOMEM;
-                                closedir(d);
-                                goto fail;
-                        }
-
-                        k = journal_file_open(fn, O_RDONLY, 0, NULL, &f);
-                        free(fn);
-
-                        if (k < 0) {
+                        } else if ((de->d_type == DT_DIR || de->d_type == DT_UNKNOWN) &&
+                                   sd_id128_from_string(de->d_name, &id) >= 0) {
 
-                                if (r == 0)
-                                        r = -k;
-                        } else {
-                                k = hashmap_put(j->files, f->path, f);
-                                if (k < 0) {
-                                        journal_file_close(f);
-                                        closedir(d);
-
-                                        r = k;
-                                        goto fail;
-                                }
+                                r = add_directory(j, p, de->d_name);
+                                if (r < 0)
+                                        log_debug("Failed to add directory %s/%s: %s", p, de->d_name, strerror(-r));
                         }
                 }
+
+                closedir(d);
         }
 
         *ret = j;
@@ -337,3 +397,165 @@ void sd_journal_close(sd_journal *j) {
 
         free(j);
 }
+
+int sd_journal_get_realtime_usec(sd_journal *j, uint64_t *ret) {
+        Object *o;
+        JournalFile *f;
+        int r;
+
+        assert(j);
+        assert(ret);
+
+        f = j->current_file;
+        if (!f)
+                return 0;
+
+        if (f->current_offset <= 0)
+                return 0;
+
+        r = journal_file_move_to_object(f, f->current_offset, OBJECT_ENTRY, &o);
+        if (r < 0)
+                return r;
+
+        *ret = le64toh(o->entry.realtime);
+        return 1;
+}
+
+int sd_journal_get_monotonic_usec(sd_journal *j, uint64_t *ret) {
+        Object *o;
+        JournalFile *f;
+        int r;
+        sd_id128_t id;
+
+        assert(j);
+        assert(ret);
+
+        f = j->current_file;
+        if (!f)
+                return 0;
+
+        if (f->current_offset <= 0)
+                return 0;
+
+        r = sd_id128_get_machine(&id);
+        if (r < 0)
+                return r;
+
+        r = journal_file_move_to_object(f, f->current_offset, OBJECT_ENTRY, &o);
+        if (r < 0)
+                return r;
+
+        if (!sd_id128_equal(id, o->entry.boot_id))
+                return 0;
+
+        *ret = le64toh(o->entry.monotonic);
+        return 1;
+
+}
+
+int sd_journal_get_field(sd_journal *j, const char *field, const void **data, size_t *size) {
+        JournalFile *f;
+        uint64_t i, n;
+        size_t field_length;
+        int r;
+        Object *o;
+
+        assert(j);
+        assert(field);
+        assert(data);
+        assert(size);
+
+        if (isempty(field) || strchr(field, '='))
+                return -EINVAL;
+
+        f = j->current_file;
+        if (!f)
+                return 0;
+
+        if (f->current_offset <= 0)
+                return 0;
+
+        r = journal_file_move_to_object(f, f->current_offset, OBJECT_ENTRY, &o);
+        if (r < 0)
+                return r;
+
+        field_length = strlen(field);
+
+        n = journal_file_entry_n_items(o);
+        for (i = 0; i < n; i++) {
+                uint64_t p, l;
+                size_t t;
+
+                p = le64toh(o->entry.items[i].object_offset);
+                r = journal_file_move_to_object(f, p, OBJECT_DATA, &o);
+                if (r < 0)
+                        return r;
+
+                l = le64toh(o->object.size) - offsetof(Object, data.payload);
+
+                if (field_length+1 > l)
+                        continue;
+
+                if (memcmp(o->data.payload, field, field_length) ||
+                    o->data.payload[field_length] != '=')
+                        continue;
+
+                t = (size_t) l;
+
+                if ((uint64_t) t != l)
+                        return -E2BIG;
+
+                *data = o->data.payload;
+                *size = t;
+
+                return 1;
+        }
+
+        return 0;
+}
+
+int sd_journal_iterate_fields(sd_journal *j, const void **data, size_t *size) {
+        JournalFile *f;
+        uint64_t p, l, n;
+        size_t t;
+        int r;
+        Object *o;
+
+        assert(j);
+        assert(data);
+        assert(size);
+
+        f = j->current_file;
+        if (!f)
+                return 0;
+
+        if (f->current_offset <= 0)
+                return 0;
+
+        r = journal_file_move_to_object(f, f->current_offset, OBJECT_ENTRY, &o);
+        if (r < 0)
+                return r;
+
+        n = journal_file_entry_n_items(o);
+        if (f->current_field >= n)
+                return 0;
+
+        p = le64toh(o->entry.items[f->current_field].object_offset);
+        r = journal_file_move_to_object(f, p, OBJECT_DATA, &o);
+        if (r < 0)
+                return r;
+
+        l = le64toh(o->object.size) - offsetof(Object, data.payload);
+        t = (size_t) l;
+
+        /* We can't read objects larger than 4G on a 32bit machine */
+        if ((uint64_t) t != l)
+                return -E2BIG;
+
+        *data = o->data.payload;
+        *size = t;
+
+        f->current_field ++;
+
+        return 1;
+}