Added C demo main program.

c/qrcodegen-demo.c

@@ -0,0 +1,70 @@
+/* 
+ * QR Code generator demo (C)
+ * 
+ * Run this command-line program with no arguments. The program
+ * computes a demonstration QR Codes and print it to the console.
+ * 
+ * Copyright (c) Project Nayuki
+ * https://www.nayuki.io/page/qr-code-generator-library
+ * 
+ * (MIT License)
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ * - The above copyright notice and this permission notice shall be included in
+ *   all copies or substantial portions of the Software.
+ * - The Software is provided "as is", without warranty of any kind, express or
+ *   implied, including but not limited to the warranties of merchantability,
+ *   fitness for a particular purpose and noninfringement. In no event shall the
+ *   authors or copyright holders be liable for any claim, damages or other
+ *   liability, whether in an action of contract, tort or otherwise, arising from,
+ *   out of or in connection with the Software or the use or other dealings in the
+ *   Software.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include "qrcodegen.h"
+
+
+// Function prototypes
+static void doBasicDemo(void);
+static void printQr(const uint8_t qrcode[], int version);
+
+
+
+// The main application program.
+int main(void) {
+	doBasicDemo();
+	return EXIT_SUCCESS;
+}
+
+
+// Creates a single QR Code, then prints it to the console.
+static void doBasicDemo() {
+	const char *text = "Hello, world!";  // User-supplied text
+	enum qrcodegen_Ecc errCorLvl = qrcodegen_Ecc_LOW;  // Error correction level
+	
+	// Make and print the QR Code symbol
+	uint8_t qrcode[qrcodegen_BUFFER_LEN_MAX];
+	uint8_t tempBuffer[qrcodegen_BUFFER_LEN_MAX];
+	int version = qrcodegen_encodeText(text, tempBuffer, qrcode, errCorLvl, 1, 40, qrcodegen_Mask_AUTO, true);
+	if (version != 0)
+		printQr(qrcode, version);
+}
+
+
+// Prints the given QR Code to the console.
+static void printQr(const uint8_t qrcode[], int version) {
+	int size = qrcodegen_getSize(version);
+	int border = 4;
+	for (int y = -border; y < size + border; y++) {
+		for (int x = -border; x < size + border; x++) {
+			fputs((qrcodegen_getModule(qrcode, version, x, y) ? "##" : "  "), stdout);
+		}
+		fputs("\n", stdout);
+	}
+}