X-Git-Url: http://git.vrable.net/?a=blobdiff_plain;f=localdb.cc;h=1509b617292b1ad86ac30eafc0d20fb95f80fee6;hb=d3c10b747ecec0acc14863fc12db9661c3f88128;hp=63a9f8349531e0fb13531b8ba7931dc4300c112d;hpb=ed5a047c1b8a8f5c43b0192e8e774b91497c9706;p=cumulus.git

diff --git a/localdb.cc b/localdb.cc
index 63a9f83..1509b61 100644
--- a/localdb.cc
+++ b/localdb.cc
@@ -22,7 +22,31 @@
 
 using std::string;
 
-void LocalDb::Open(const char *path)
+/* Helper function to prepare a statement for execution in the current
+ * database. */
+sqlite3_stmt *LocalDb::Prepare(const char *sql)
+{
+    sqlite3_stmt *stmt;
+    int rc;
+    const char *tail;
+
+    rc = sqlite3_prepare_v2(db, sql, strlen(sql), &stmt, &tail);
+    if (rc != SQLITE_OK) {
+        ReportError(rc);
+        throw IOException(string("Error preparing statement: ") + sql);
+    }
+
+    return stmt;
+}
+
+void LocalDb::ReportError(int rc)
+{
+    fprintf(stderr, "Result code: %d\n", rc);
+    fprintf(stderr, "Error message: %s\n", sqlite3_errmsg(db));
+}
+
+void LocalDb::Open(const char *path, const char *snapshot_name,
+                   const char *snapshot_scheme)
 {
     int rc;
 
@@ -39,45 +63,361 @@ void LocalDb::Open(const char *path)
         sqlite3_close(db);
         throw IOException("Error starting transaction");
     }
+
+    sqlite3_extended_result_codes(db, 1);
+
+    /* Insert this snapshot into the database, and determine the integer key
+     * which will be used to identify it. */
+    sqlite3_stmt *stmt = Prepare("insert into "
+                                 "snapshots(name, scheme, timestamp) "
+                                 "values (?, ?, julianday('now'))");
+    sqlite3_bind_text(stmt, 1, snapshot_name, strlen(snapshot_name),
+                      SQLITE_TRANSIENT);
+    if (snapshot_scheme == NULL)
+        sqlite3_bind_null(stmt, 2);
+    else
+        sqlite3_bind_text(stmt, 2, snapshot_scheme, strlen(snapshot_scheme),
+                          SQLITE_TRANSIENT);
+
+    rc = sqlite3_step(stmt);
+    if (rc != SQLITE_DONE) {
+        ReportError(rc);
+        sqlite3_close(db);
+        throw IOException("Database execution error!");
+    }
+
+    snapshotid = sqlite3_last_insert_rowid(db);
+    sqlite3_finalize(stmt);
+    if (snapshotid == 0) {
+        ReportError(rc);
+        sqlite3_close(db);
+        throw IOException("Find snapshot id");
+    }
+
+    /* Create a temporary table which will be used to keep track of the objects
+     * used by this snapshot.  When the database is closed, we will summarize
+     * the results of this table into segments_used. */
+    rc = sqlite3_exec(db,
+                      "create temporary table snapshot_refs ("
+                      "    segmentid integer not null,"
+                      "    object text not null,"
+                      "    size integer not null"
+                      ")", NULL, NULL, NULL);
+    if (rc != SQLITE_OK) {
+        ReportError(rc);
+        sqlite3_close(db);
+        throw IOException("Database initialization");
+    }
+    rc = sqlite3_exec(db,
+                      "create unique index snapshot_refs_index "
+                      "on snapshot_refs(segmentid, object)",
+                      NULL, NULL, NULL);
+    if (rc != SQLITE_OK) {
+        ReportError(rc);
+        sqlite3_close(db);
+        throw IOException("Database initialization");
+    }
 }
 
 void LocalDb::Close()
 {
     int rc;
+
+    /* Summarize the snapshot_refs table into segments_used. */
+    sqlite3_stmt *stmt = Prepare("insert into segments_used "
+                                 "select ? as snapshotid, segmentid, "
+                                 "cast(used as real) / size as utilization "
+                                 "from "
+                                 "(select segmentid, sum(size) as used "
+                                 "from snapshot_refs group by segmentid) "
+                                 "join segments using (segmentid)");
+    sqlite3_bind_int64(stmt, 1, snapshotid);
+    rc = sqlite3_step(stmt);
+    if (rc != SQLITE_OK && rc != SQLITE_DONE) {
+        ReportError(rc);
+        sqlite3_close(db);
+        fprintf(stderr, "DATABASE ERROR: Unable to create segment summary!\n");
+    }
+    sqlite3_finalize(stmt);
+
+    /* Commit changes to the database and close. */
     rc = sqlite3_exec(db, "commit", NULL, NULL, NULL);
     if (rc != SQLITE_OK) {
-        fprintf(stderr, "Can't commit database!\n");
+        fprintf(stderr, "DATABASE ERROR: Can't commit database!\n");
+        ReportError(rc);
     }
     sqlite3_close(db);
 }
 
+int64_t LocalDb::SegmentToId(const string &segment)
+{
+    int rc;
+    sqlite3_stmt *stmt;
+    int64_t result;
+
+    stmt = Prepare("insert or ignore into segments(segment) values (?)");
+    sqlite3_bind_text(stmt, 1, segment.c_str(), segment.size(),
+                      SQLITE_TRANSIENT);
+    rc = sqlite3_step(stmt);
+    if (rc != SQLITE_DONE) {
+        throw IOException("Could not execute INSERT statement!");
+    }
+    sqlite3_finalize(stmt);
+
+    stmt = Prepare("select segmentid from segments where segment = ?");
+    sqlite3_bind_text(stmt, 1, segment.c_str(), segment.size(),
+                      SQLITE_TRANSIENT);
+
+    rc = sqlite3_step(stmt);
+    if (rc == SQLITE_DONE) {
+        throw IOException("No segment found by id");
+    } else if (rc == SQLITE_ROW) {
+        result = sqlite3_column_int64(stmt, 0);
+    } else {
+        throw IOException("Error executing find segment by id query");
+    }
+
+    sqlite3_finalize(stmt);
+
+    return result;
+}
+
+string LocalDb::IdToSegment(int64_t segmentid)
+{
+    int rc;
+    sqlite3_stmt *stmt;
+    string result;
+
+    stmt = Prepare("select segment from segments where segmentid = ?");
+    sqlite3_bind_int64(stmt, 1, segmentid);
+
+    rc = sqlite3_step(stmt);
+    if (rc == SQLITE_DONE) {
+        throw IOException("No segment found by id");
+    } else if (rc == SQLITE_ROW) {
+        result = (const char *)sqlite3_column_text(stmt, 0);
+    } else {
+        throw IOException("Error executing find segment by id query");
+    }
+
+    sqlite3_finalize(stmt);
+
+    return result;
+}
+
 void LocalDb::StoreObject(const ObjectReference& ref,
-                          const string &checksum, int64_t size)
+                          const string &checksum, int64_t size,
+                          double age)
 {
     int rc;
     sqlite3_stmt *stmt;
-    static const char s[] =
-        "insert into block_index(segment, object, checksum, size) "
-        "values (?, ?, ?, ?)";
-    const char *tail;
 
-    rc = sqlite3_prepare_v2(db, s, strlen(s), &stmt, &tail);
-    if (rc != SQLITE_OK) {
-        return;
+    if (age == 0.0) {
+        stmt = Prepare("insert into block_index("
+                       "segmentid, object, checksum, size, timestamp) "
+                       "values (?, ?, ?, ?, julianday('now'))");
+    } else {
+        stmt = Prepare("insert into block_index("
+                       "segmentid, object, checksum, size, timestamp) "
+                       "values (?, ?, ?, ?, ?)");
     }
 
-    string seg = ref.get_segment();
-    sqlite3_bind_text(stmt, 1, seg.c_str(), seg.size(), SQLITE_TRANSIENT);
+    sqlite3_bind_int64(stmt, 1, SegmentToId(ref.get_segment()));
     string obj = ref.get_sequence();
     sqlite3_bind_text(stmt, 2, obj.c_str(), obj.size(), SQLITE_TRANSIENT);
     sqlite3_bind_text(stmt, 3, checksum.c_str(), checksum.size(),
                       SQLITE_TRANSIENT);
     sqlite3_bind_int64(stmt, 4, size);
+    if (age != 0.0)
+        sqlite3_bind_double(stmt, 5, age);
 
     rc = sqlite3_step(stmt);
     if (rc != SQLITE_DONE) {
         fprintf(stderr, "Could not execute INSERT statement!\n");
+        ReportError(rc);
     }
 
     sqlite3_finalize(stmt);
 }
+
+ObjectReference LocalDb::FindObject(const string &checksum, int64_t size)
+{
+    int rc;
+    sqlite3_stmt *stmt;
+    ObjectReference ref;
+
+    stmt = Prepare("select segmentid, object from block_index "
+                   "where checksum = ? and size = ? and expired is null");
+    sqlite3_bind_text(stmt, 1, checksum.c_str(), checksum.size(),
+                      SQLITE_TRANSIENT);
+    sqlite3_bind_int64(stmt, 2, size);
+
+    rc = sqlite3_step(stmt);
+    if (rc == SQLITE_DONE) {
+    } else if (rc == SQLITE_ROW) {
+        ref = ObjectReference(IdToSegment(sqlite3_column_int64(stmt, 0)),
+                              (const char *)sqlite3_column_text(stmt, 1));
+    } else {
+        fprintf(stderr, "Could not execute SELECT statement!\n");
+        ReportError(rc);
+    }
+
+    sqlite3_finalize(stmt);
+
+    return ref;
+}
+
+bool LocalDb::IsOldObject(const string &checksum, int64_t size, double *age,
+                          int *group)
+{
+    int rc;
+    sqlite3_stmt *stmt;
+    bool found = false;
+
+    stmt = Prepare("select segmentid, object, timestamp, expired "
+                   "from block_index where checksum = ? and size = ?");
+    sqlite3_bind_text(stmt, 1, checksum.c_str(), checksum.size(),
+                      SQLITE_TRANSIENT);
+    sqlite3_bind_int64(stmt, 2, size);
+
+    rc = sqlite3_step(stmt);
+    if (rc == SQLITE_DONE) {
+        found = false;
+    } else if (rc == SQLITE_ROW) {
+        found = true;
+        *age = sqlite3_column_double(stmt, 2);
+        *group = sqlite3_column_int(stmt, 3);
+    } else {
+        fprintf(stderr, "Could not execute SELECT statement!\n");
+        ReportError(rc);
+    }
+
+    sqlite3_finalize(stmt);
+
+    return found;
+}
+
+/* Does this object still exist in the database (and not expired)? */
+bool LocalDb::IsAvailable(const ObjectReference &ref)
+{
+    int rc;
+    sqlite3_stmt *stmt;
+    bool found = false;
+
+    // Special objects (such as the zero object) aren't stored in segments, and
+    // so are always available.
+    if (!ref.is_normal())
+        return true;
+
+    stmt = Prepare("select count(*) from block_index "
+                   "where segmentid = ? and object = ? and expired is null");
+    sqlite3_bind_int64(stmt, 1, SegmentToId(ref.get_segment()));
+    sqlite3_bind_text(stmt, 2, ref.get_sequence().c_str(),
+                      ref.get_sequence().size(), SQLITE_TRANSIENT);
+
+    rc = sqlite3_step(stmt);
+    if (rc == SQLITE_DONE) {
+        found = false;
+    } else if (rc == SQLITE_ROW) {
+        if (sqlite3_column_int(stmt, 0) > 0)
+            found = true;
+    } else {
+        fprintf(stderr, "Could not execute SELECT statement!\n");
+        ReportError(rc);
+    }
+
+    sqlite3_finalize(stmt);
+
+    return found;
+}
+
+void LocalDb::UseObject(const ObjectReference& ref)
+{
+    int rc;
+    sqlite3_stmt *stmt;
+
+    if (!ref.is_normal())
+        return;
+
+    stmt = Prepare("insert or ignore into snapshot_refs "
+                   "select segmentid, object, size from block_index "
+                   "where segmentid = ? and object = ?");
+    sqlite3_bind_int64(stmt, 1, SegmentToId(ref.get_segment()));
+    string obj = ref.get_sequence();
+    sqlite3_bind_text(stmt, 2, obj.c_str(), obj.size(), SQLITE_TRANSIENT);
+
+    rc = sqlite3_step(stmt);
+    if (rc != SQLITE_DONE) {
+        fprintf(stderr, "Could not execute INSERT statement!\n");
+        ReportError(rc);
+    }
+
+    sqlite3_finalize(stmt);
+}
+
+void LocalDb::SetSegmentChecksum(const std::string &segment,
+                                 const std::string &path,
+                                 const std::string &checksum)
+{
+    int rc;
+    sqlite3_stmt *stmt;
+
+    stmt = Prepare("update segments set path = ?, checksum = ?, "
+                   "size = (select sum(size) from block_index "
+                   "        where segmentid = ?) "
+                   "where segmentid = ?");
+    sqlite3_bind_text(stmt, 1, path.c_str(), path.size(),
+                      SQLITE_TRANSIENT);
+    sqlite3_bind_text(stmt, 2, checksum.c_str(), checksum.size(),
+                      SQLITE_TRANSIENT);
+    sqlite3_bind_int64(stmt, 3, SegmentToId(segment));
+    sqlite3_bind_int64(stmt, 4, SegmentToId(segment));
+
+    rc = sqlite3_step(stmt);
+    if (rc != SQLITE_DONE) {
+        fprintf(stderr, "Could not update segment checksum in database!\n");
+        ReportError(rc);
+    }
+
+    sqlite3_finalize(stmt);
+}
+
+bool LocalDb::GetSegmentChecksum(const string &segment,
+                                 string *seg_path,
+                                 string *seg_checksum)
+{
+    int rc;
+    sqlite3_stmt *stmt;
+    ObjectReference ref;
+    int found = false;
+
+    stmt = Prepare("select path, checksum from segments where segment = ?");
+    sqlite3_bind_text(stmt, 1, segment.c_str(), segment.size(),
+                      SQLITE_TRANSIENT);
+
+    rc = sqlite3_step(stmt);
+    if (rc == SQLITE_DONE) {
+    } else if (rc == SQLITE_ROW) {
+        found = true;
+        const char *val;
+
+        val = (const char *)sqlite3_column_text(stmt, 0);
+        if (val == NULL)
+            found = false;
+        else
+            *seg_path = val;
+
+        val = (const char *)sqlite3_column_text(stmt, 1);
+        if (val == NULL)
+            found = false;
+        else
+            *seg_checksum = val;
+    } else {
+        fprintf(stderr, "Could not execute SELECT statement!\n");
+        ReportError(rc);
+    }
+
+    sqlite3_finalize(stmt);
+
+    return found;
+}