Add code to create database.

Makefile

@@ -20,8 +20,8 @@ INCFLAGS=
 LDFLAGS=-lsqlite3
 DEFS=
 CFLAGS=$(INCFLAGS) -std=c99 -Wall -Wextra -Wfatal-errors -Werror
-HDRS=src/arg_parse.h src/util.h
+HDRS=src/arg_parse.h src/util.h src/db.h
-OBJS=src/main.o src/arg_parse.o
+OBJS=src/main.o src/arg_parse.o src/db.o
 VERSION=1.0
 
 ifeq ($(PREFIX),)

src/db.c

@@ -0,0 +1,76 @@
+/*
+ * Copyright (C) 2024  Nicolás Ortega Froysa <nicolas@ortegas.org>
+ * Nicolás Ortega Froysa <nicolas@ortegas.org>
+ *
+ * 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 3 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.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include "db.h"
+
+#include <sqlite3.h>
+#include <unistd.h>
+#include <sys/stat.h>
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+static sqlite3 *db = NULL;
+static const  int db_version = 1;
+
+int db_open(void) {
+	const char *xdg_data_home;
+	char *db_path;
+	int new_db = 0;
+	int rc;
+
+	if(!(xdg_data_home = getenv("XDG_DATA_HOME"))) {
+		printf("Cannot find environment variable XDG_DATA_HOME. Please define it before continuing. E.g.:\nexport XDG_DATA_HOME=\"$HOME/.local/share\"\n");
+		return 0;
+	}
+
+	db_path = malloc(strlen(xdg_data_home) + strlen("/menu-helper") + strlen("/recipes.db") + 1);
+	strcpy(db_path, xdg_data_home);
+	strcat(db_path, "/menu-helper");
+
+	if(access(db_path, F_OK) != 0) {
+		printf("Creating database: %s\n", db_path);
+		mkdir(db_path, 0700);
+		new_db = 1;
+	}
+
+	strcat(db_path, "/recipes.db");
+
+	rc = sqlite3_open(db_path, &db);
+	free(db_path);
+
+	if(rc == SQLITE_OK && new_db) {
+		char insert_version_stmt[64];
+		sqlite3_exec(db, "CREATE TABLE db_version(version INTEGER UNIQUE NOT NULL);", NULL, NULL, NULL);
+		snprintf(insert_version_stmt, 64, "INSERT INTO db_version VALUES(%d);", db_version);
+		sqlite3_exec(db, insert_version_stmt, NULL, NULL, NULL);
+		sqlite3_exec(db, "CREATE TABLE tags(id INTEGER PRIMARY KEY AUTOINCREMENT, name STRING UNIQUE);", NULL, NULL, NULL);
+		sqlite3_exec(db, "CREATE TABLE ingredients(id INTEGER PRIMARY KEY AUTOINCREMENT, name STRING UNIQUE);", NULL, NULL, NULL);
+		sqlite3_exec(db, "CREATE TABLE recipes(id INTEGER PRIMARY KEY AUTOINCREMENT, name STRING UNIQUE, description STRING);", NULL, NULL, NULL);
+		sqlite3_exec(db, "CREATE TABLE recipe_tag(recipe_id INTEGER REFERENCES recipes(id) ON DELETE CASCADE, tag_id INTEGER REFERENCES tags(id) ON DELETE CASCADE);", NULL, NULL, NULL);
+		sqlite3_exec(db, "CREATE TABLE recipe_ingredient(recipe_id INTEGER REFERENCES recipes(id) ON DELETE CASCADE, ingredient_id INTEGER REFERENCES ingredients(id) ON DELETE CASCADE);", NULL, NULL, NULL);
+	}
+
+	return rc == SQLITE_OK;
+}
+
+void db_close(void) {
+	if(!db)
+		return;
+
+	sqlite3_close(db);
+}

src/db.h

@@ -0,0 +1,21 @@
+/*
+ * Copyright (C) 2024  Nicolás Ortega Froysa <nicolas@ortegas.org>
+ * Nicolás Ortega Froysa <nicolas@ortegas.org>
+ *
+ * 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 3 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.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#pragma once
+
+int db_open(void);
+void db_close(void);