1 files changed, 277 insertions, 0 deletions
diff --git a/src/fluent-bit/plugins/in_tail/tail_db.c b/src/fluent-bit/plugins/in_tail/tail_db.c
new file mode 100644
index 000000000..664963b6d
--- /dev/null
+++ b/src/fluent-bit/plugins/in_tail/tail_db.c
@@ -0,0 +1,277 @@
+/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+
+/*  Fluent Bit
+ *  ==========
+ *  Copyright (C) 2015-2022 The Fluent Bit Authors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+#include <fluent-bit/flb_info.h>
+#include <fluent-bit/flb_input_plugin.h>
+#include <fluent-bit/flb_sqldb.h>
+
+#include "tail_db.h"
+#include "tail_sql.h"
+#include "tail_file.h"
+
+struct query_status {
+    int id;
+    int rows;
+    int64_t offset;
+};
+
+/* Open or create database required by tail plugin */
+struct flb_sqldb *flb_tail_db_open(const char *path,
+                                   struct flb_input_instance *in,
+                                   struct flb_tail_config *ctx,
+                                   struct flb_config *config)
+{
+    int ret;
+    char tmp[64];
+    struct flb_sqldb *db;
+
+    /* Open/create the database */
+    db = flb_sqldb_open(path, in->name, config);
+    if (!db) {
+        return NULL;
+    }
+
+    /* Create table schema if it don't exists */
+    ret = flb_sqldb_query(db, SQL_CREATE_FILES, NULL, NULL);
+    if (ret != FLB_OK) {
+        flb_plg_error(ctx->ins, "db: could not create 'in_tail_files' table");
+        flb_sqldb_close(db);
+        return NULL;
+    }
+
+    if (ctx->db_sync >= 0) {
+        snprintf(tmp, sizeof(tmp) - 1, SQL_PRAGMA_SYNC,
+                 ctx->db_sync);
+        ret = flb_sqldb_query(db, tmp, NULL, NULL);
+        if (ret != FLB_OK) {
+            flb_plg_error(ctx->ins, "db could not set pragma 'sync'");
+            flb_sqldb_close(db);
+            return NULL;
+        }
+    }
+
+    if (ctx->db_locking == FLB_TRUE) {
+        ret = flb_sqldb_query(db, SQL_PRAGMA_LOCKING_MODE, NULL, NULL);
+        if (ret != FLB_OK) {
+            flb_plg_error(ctx->ins, "db: could not set pragma 'locking_mode'");
+            flb_sqldb_close(db);
+            return NULL;
+        }
+    }
+
+    if (ctx->db_journal_mode) {
+        snprintf(tmp, sizeof(tmp) - 1, SQL_PRAGMA_JOURNAL_MODE,
+                 ctx->db_journal_mode);
+        ret = flb_sqldb_query(db, tmp, NULL, NULL);
+        if (ret != FLB_OK) {
+            flb_plg_error(ctx->ins, "db could not set pragma 'journal_mode'");
+            flb_sqldb_close(db);
+            return NULL;
+        }
+    }
+
+    return db;
+}
+
+int flb_tail_db_close(struct flb_sqldb *db)
+{
+    flb_sqldb_close(db);
+    return 0;
+}
+
+/*
+ * Check if an file inode exists in the database. Return FLB_TRUE or
+ * FLB_FALSE
+ */
+static int db_file_exists(struct flb_tail_file *file,
+                          struct flb_tail_config *ctx,
+                          uint64_t *id, uint64_t *inode, off_t *offset)
+{
+    int ret;
+    int exists = FLB_FALSE;
+
+    /* Bind parameters */
+    sqlite3_bind_int64(ctx->stmt_get_file, 1, file->inode);
+    ret = sqlite3_step(ctx->stmt_get_file);
+
+    if (ret == SQLITE_ROW) {
+        exists = FLB_TRUE;
+
+        /* id: column 0 */
+        *id = sqlite3_column_int64(ctx->stmt_get_file, 0);
+
+        /* offset: column 2 */
+        *offset = sqlite3_column_int64(ctx->stmt_get_file, 2);
+
+        /* inode: column 3 */
+        *inode = sqlite3_column_int64(ctx->stmt_get_file, 3);
+    }
+    else if (ret == SQLITE_DONE) {
+        /* all good */
+    }
+    else {
+        exists = -1;
+    }
+
+    sqlite3_clear_bindings(ctx->stmt_get_file);
+    sqlite3_reset(ctx->stmt_get_file);
+
+    return exists;
+
+}
+
+static int db_file_insert(struct flb_tail_file *file, struct flb_tail_config *ctx)
+
+{
+    int ret;
+    time_t created;
+
+    /* Register the file */
+    created = time(NULL);
+
+    /* Bind parameters */
+    sqlite3_bind_text(ctx->stmt_insert_file, 1, file->name, -1, 0);
+    sqlite3_bind_int64(ctx->stmt_insert_file, 2, file->offset);
+    sqlite3_bind_int64(ctx->stmt_insert_file, 3, file->inode);
+    sqlite3_bind_int64(ctx->stmt_insert_file, 4, created);
+
+    /* Run the insert */
+    ret = sqlite3_step(ctx->stmt_insert_file);
+    if (ret != SQLITE_DONE) {
+        sqlite3_clear_bindings(ctx->stmt_insert_file);
+        sqlite3_reset(ctx->stmt_insert_file);
+        flb_plg_error(ctx->ins, "cannot execute insert file %s inode=%lu",
+                      file->name, file->inode);
+        return -1;
+    }
+
+    sqlite3_clear_bindings(ctx->stmt_insert_file);
+    sqlite3_reset(ctx->stmt_insert_file);
+
+    /* Get the database ID for this file */
+    return flb_sqldb_last_id(ctx->db);
+}
+
+int flb_tail_db_file_set(struct flb_tail_file *file,
+                         struct flb_tail_config *ctx)
+{
+    int ret;
+    uint64_t id = 0;
+    off_t offset = 0;
+    uint64_t inode = 0;
+
+    /* Check if the file exists */
+    ret = db_file_exists(file, ctx, &id, &inode, &offset);
+    if (ret == -1) {
+        flb_plg_error(ctx->ins, "cannot execute query to check inode: %lu",
+                      file->inode);
+        return -1;
+    }
+
+    if (ret == FLB_FALSE) {
+        /* Get the database ID for this file */
+        file->db_id = db_file_insert(file, ctx);
+    }
+    else {
+        file->db_id = id;
+        file->offset = offset;
+    }
+
+    return 0;
+}
+
+/* Update Offset v2 */
+int flb_tail_db_file_offset(struct flb_tail_file *file,
+                            struct flb_tail_config *ctx)
+{
+    int ret;
+
+    /* Bind parameters */
+    sqlite3_bind_int64(ctx->stmt_offset, 1, file->offset);
+    sqlite3_bind_int64(ctx->stmt_offset, 2, file->db_id);
+
+    ret = sqlite3_step(ctx->stmt_offset);
+
+    if (ret != SQLITE_DONE) {
+        sqlite3_clear_bindings(ctx->stmt_offset);
+        sqlite3_reset(ctx->stmt_offset);
+        return -1;
+    }
+
+    /* Verify number of updated rows */
+    ret = sqlite3_changes(ctx->db->handler);
+    if (ret == 0) {
+        /*
+         * 'someone' like you 'the reader' or another user has deleted the database
+         * entry, just restore it.
+         */
+        file->db_id = db_file_insert(file, ctx);
+    }
+
+    sqlite3_clear_bindings(ctx->stmt_offset);
+    sqlite3_reset(ctx->stmt_offset);
+
+    return 0;
+}
+
+/* Mark a file as rotated v2 */
+int flb_tail_db_file_rotate(const char *new_name,
+                            struct flb_tail_file *file,
+                            struct flb_tail_config *ctx)
+{
+    int ret;
+
+    /* Bind parameters */
+    sqlite3_bind_text(ctx->stmt_rotate_file, 1, new_name, -1, 0);
+    sqlite3_bind_int64(ctx->stmt_rotate_file, 2, file->db_id);
+
+    ret = sqlite3_step(ctx->stmt_rotate_file);
+
+    sqlite3_clear_bindings(ctx->stmt_rotate_file);
+    sqlite3_reset(ctx->stmt_rotate_file);
+
+    if (ret != SQLITE_DONE) {
+        return -1;
+    }
+
+    return 0;
+}
+
+/* Delete file entry from the database */
+int flb_tail_db_file_delete(struct flb_tail_file *file,
+                            struct flb_tail_config *ctx)
+{
+    int ret;
+
+    /* Bind parameters */
+    sqlite3_bind_int64(ctx->stmt_delete_file, 1, file->db_id);
+    ret = sqlite3_step(ctx->stmt_delete_file);
+
+    sqlite3_clear_bindings(ctx->stmt_delete_file);
+    sqlite3_reset(ctx->stmt_delete_file);
+
+    if (ret != SQLITE_DONE) {
+        flb_plg_error(ctx->ins, "db: error deleting entry from database: %s",
+                      file->name);
+        return -1;
+    }
+
+    flb_plg_debug(ctx->ins, "db: file deleted from database: %s", file->name);
+    return 0;
+}