Data commit

Task/Variable-length-quantity/C/variable-length-quantity-1.c

@@ -0,0 +1,43 @@
+#include <stdio.h>
+#include <stdint.h>
+
+void to_seq(uint64_t x, uint8_t *out)
+{
+	int i, j;
+	for (i = 9; i > 0; i--) {
+		if (x & 127ULL << i * 7) break;
+	}
+	for (j = 0; j <= i; j++)
+		out[j] = ((x >> ((i - j) * 7)) & 127) | 128;
+
+	out[i] ^= 128;
+}
+
+uint64_t from_seq(uint8_t *in)
+{
+	uint64_t r = 0;
+
+	do {
+		r = (r << 7) | (uint64_t)(*in & 127);
+	} while (*in++ & 128);
+
+	return r;
+}
+
+int main()
+{
+	uint8_t s[10];
+	uint64_t x[] = { 0x7f, 0x4000, 0, 0x3ffffe, 0x1fffff, 0x200000, 0x3311a1234df31413ULL};
+
+	int i, j;
+	for (j = 0; j < sizeof(x)/8; j++) {
+		to_seq(x[j], s);
+		printf("seq from %llx: [ ", x[j]);
+
+		i = 0;
+		do { printf("%02x ", s[i]); } while ((s[i++] & 128));
+		printf("] back: %llx\n", from_seq(s));
+	}
+
+	return 0;
+}

Task/Variable-length-quantity/C/variable-length-quantity-2.c

@@ -0,0 +1,7 @@
+seq from 7f: [ 7f ] back: 7f
+seq from 4000: [ 81 80 00 ] back: 4000
+seq from 0: [ 00 ] back: 0
+seq from 3ffffe: [ 81 ff ff 7e ] back: 3ffffe
+seq from 1fffff: [ ff ff 7f ] back: 1fffff
+seq from 200000: [ 81 80 80 00 ] back: 200000
+seq from 3311a1234df31413: [ b3 88 e8 a4 b4 ef cc a8 13 ] back: 3311a1234df31413