lib: introduce new northbound API

Signed-off-by: Renato Westphal <renato@opensourcerouting.org>

1 files changed, 325 insertions, 0 deletions

diff --git a/lib/db.c b/lib/db.c
new file mode 100644
index 000000000..32ba83b65
--- /dev/null
+++ b/lib/db.c
@@ -0,0 +1,325 @@
+/*
+ * Copyright (c) 2018 Rafael Zalamena <rzalamena@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This program 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 General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; see the file COPYING; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/*
+ * Copyright (c) 2016 Rafael Zalamena <rzalamena@gmail.com>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <zebra.h>
+
+#include "db.h"
+#include "log.h"
+
+static struct sqlite3 *dbp;
+
+/*
+ * Initialize the database in path.
+ *
+ * It's possible to use in memory database with ':memory:' path.
+ */
+int db_init(const char *path_fmt, ...)
+{
+	char path[BUFSIZ];
+	va_list ap;
+
+	if (dbp)
+		return -1;
+
+	va_start(ap, path_fmt);
+	vsnprintf(path, sizeof(path), path_fmt, ap);
+	va_end(ap);
+
+	if (sqlite3_open_v2(path, &dbp,
+			    (SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE), NULL)
+	    != SQLITE_OK) {
+		if (dbp == NULL) {
+			zlog_warn("%s: failed to open dabatase '%s'", __func__,
+				  path);
+			return -1;
+		}
+
+		zlog_warn("%s: failed to open database '%s': %s", __func__,
+			  path, sqlite3_errmsg(dbp));
+		if (sqlite3_close_v2(dbp) != SQLITE_OK)
+			zlog_warn("%s: failed to terminate database", __func__);
+		dbp = NULL;
+		return -1;
+	}
+
+	return 0;
+}
+
+/* Closes the database if open. */
+int db_close(void)
+{
+	if (dbp == NULL)
+		return 0;
+
+	if (sqlite3_close_v2(dbp) != SQLITE_OK) {
+		zlog_warn("%s: failed to terminate database", __func__);
+		return -1;
+	}
+	return 0;
+}
+
+/* Helper function to handle formating. */
+static int db_vbindf(struct sqlite3_stmt *ss, const char *fmt, va_list vl)
+{
+	const char *sptr = fmt;
+	int column = 1;
+	const char *str;
+	void *blob;
+	uint64_t uinteger64;
+	uint32_t uinteger;
+	int vlen;
+
+	while (*sptr) {
+		if (*sptr != '%') {
+			sptr++;
+			continue;
+		}
+		if (sptr++ && *sptr == 0)
+			break;
+
+		switch (*sptr) {
+		case 'i':
+			uinteger = va_arg(vl, uint32_t);
+			if (sqlite3_bind_int(ss, column++, uinteger)
+			    != SQLITE_OK)
+				return -1;
+			break;
+		case 'd':
+			uinteger64 = va_arg(vl, uint64_t);
+			if (sqlite3_bind_int64(ss, column++, uinteger64)
+			    != SQLITE_OK)
+				return -1;
+			break;
+		case 's':
+			str = va_arg(vl, const char *);
+			vlen = va_arg(vl, int);
+			if (sqlite3_bind_text(ss, column++, str, vlen,
+					      SQLITE_STATIC)
+			    != SQLITE_OK)
+				return -1;
+			break;
+		case 'b':
+			blob = va_arg(vl, void *);
+			vlen = va_arg(vl, int);
+			if (sqlite3_bind_blob(ss, column++, blob, vlen,
+					      SQLITE_STATIC)
+			    != SQLITE_OK)
+				return -1;
+			break;
+		case 'n':
+			if (sqlite3_bind_null(ss, column++) != SQLITE_OK)
+				return -1;
+			break;
+		default:
+			zlog_warn("%s: invalid format '%c'", __func__, *sptr);
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * Binds values using format to the database query.
+ *
+ * Might be used to bind variables to a query, insert or update.
+ */
+int db_bindf(struct sqlite3_stmt *ss, const char *fmt, ...)
+{
+	va_list vl;
+	int result;
+
+	va_start(vl, fmt);
+	result = db_vbindf(ss, fmt, vl);
+	va_end(vl);
+
+	return result;
+}
+
+/* Prepares an statement to the database with the statement length. */
+struct sqlite3_stmt *db_prepare_len(const char *stmt, int stmtlen)
+{
+	struct sqlite3_stmt *ss;
+	int c;
+
+	if (dbp == NULL)
+		return NULL;
+
+	c = sqlite3_prepare_v2(dbp, stmt, stmtlen, &ss, NULL);
+	if (ss == NULL) {
+		zlog_warn("%s: failed to prepare (%d:%s)", __func__, c,
+			  sqlite3_errmsg(dbp));
+		return NULL;
+	}
+
+	return ss;
+}
+
+/* Prepares an statement to the database. */
+struct sqlite3_stmt *db_prepare(const char *stmt)
+{
+	return db_prepare_len(stmt, strlen(stmt));
+}
+
+/* Run a prepared statement. */
+int db_run(struct sqlite3_stmt *ss)
+{
+	int result;
+
+	result = sqlite3_step(ss);
+	switch (result) {
+	case SQLITE_BUSY:
+		/* TODO handle busy database. */
+		break;
+
+	case SQLITE_OK:
+	/*
+	 * SQLITE_DONE just causes confusion since it means the query went OK,
+	 * but it has a different value.
+	 */
+	case SQLITE_DONE:
+		result = SQLITE_OK;
+		break;
+
+	case SQLITE_ROW:
+		/* NOTHING */
+		/* It is expected to receive SQLITE_ROW on search queries. */
+		break;
+
+	default:
+		zlog_warn("%s: step failed (%d:%s)", __func__, result,
+			  sqlite3_errstr(result));
+	}
+
+	return result;
+}
+
+/* Helper function to load format to variables. */
+static int db_vloadf(struct sqlite3_stmt *ss, const char *fmt, va_list vl)
+{
+	const char *sptr = fmt;
+	int column = 0;
+	const char **str;
+	void *blob;
+	const void *blobsrc;
+	uint64_t *uinteger64;
+	uint32_t *uinteger;
+	int vlen;
+	int dlen;
+	int columncount;
+
+	columncount = sqlite3_column_count(ss);
+	if (columncount == 0)
+		return -1;
+
+	while (*sptr) {
+		if (*sptr != '%') {
+			sptr++;
+			continue;
+		}
+		if (sptr++ && *sptr == 0)
+			break;
+
+		switch (*sptr) {
+		case 'i':
+			uinteger = va_arg(vl, uint32_t *);
+			*uinteger = sqlite3_column_int(ss, column);
+			break;
+		case 'd':
+			uinteger64 = va_arg(vl, uint64_t *);
+			*uinteger64 = sqlite3_column_int64(ss, column);
+			break;
+		case 's':
+			str = va_arg(vl, const char **);
+			*str = (const char *)sqlite3_column_text(ss, column);
+			break;
+		case 'b':
+			blob = va_arg(vl, void *);
+			vlen = va_arg(vl, int);
+			dlen = sqlite3_column_bytes(ss, column);
+			blobsrc = sqlite3_column_blob(ss, column);
+			memcpy(blob, blobsrc, MIN(vlen, dlen));
+			break;
+		default:
+			zlog_warn("%s: invalid format '%c'", __func__, *sptr);
+			return -1;
+		}
+
+		column++;
+	}
+
+	return 0;
+}
+
+/* Function to load format from database row. */
+int db_loadf(struct sqlite3_stmt *ss, const char *fmt, ...)
+{
+	va_list vl;
+	int result;
+
+	va_start(vl, fmt);
+	result = db_vloadf(ss, fmt, vl);
+	va_end(vl);
+
+	return result;
+}
+
+/* Finalize query and return memory. */
+void db_finalize(struct sqlite3_stmt **ss)
+{
+	sqlite3_finalize(*ss);
+	*ss = NULL;
+}
+
+/* Execute one or more statements. */
+int db_execute(const char *stmt_fmt, ...)
+{
+	char stmt[BUFSIZ];
+	va_list ap;
+
+	if (dbp == NULL)
+		return -1;
+
+	va_start(ap, stmt_fmt);
+	vsnprintf(stmt, sizeof(stmt), stmt_fmt, ap);
+	va_end(ap);
+
+	if (sqlite3_exec(dbp, stmt, NULL, 0, NULL) != SQLITE_OK) {
+		zlog_warn("%s: failed to execute statement(s): %s", __func__,
+			  sqlite3_errmsg(dbp));
+		return -1;
+	}
+
+	return 0;
+}