libmisc: endian.h: Add 64-bit versions

2 files changed, 103 insertions, 16 deletions

diff --git a/libmisc/include/libmisc/endian.h b/libmisc/include/libmisc/endian.h
index b1bc55c..665a8c8 100644
--- a/libmisc/include/libmisc/endian.h
+++ b/libmisc/include/libmisc/endian.h
@@ -1,6 +1,6 @@
 /* libmisc/endian.h - Endian-conversion helpers
  *
- * Copyright (C) 2024  Luke T. Shumaker <lukeshu@lukeshu.com>
+ * Copyright (C) 2024-2025  Luke T. Shumaker <lukeshu@lukeshu.com>
  * SPDX-License-Identifier: AGPL-3.0-or-later
  */
 
@@ -71,6 +71,45 @@ static inline uint32_t uint32be_unmarshal(uint32be_t in) {
 	return uint32be_decode(in.octets);
 }
 
+typedef struct {
+	uint8_t octets[8];
+} uint64be_t;
+static_assert(sizeof(uint64be_t) == 8);
+
+static inline size_t uint64be_encode(uint8_t *out, uint64_t in) {
+	out[0] = (uint8_t)((in >> 56) & 0xFF);
+	out[1] = (uint8_t)((in >> 48) & 0xFF);
+	out[2] = (uint8_t)((in >> 40) & 0xFF);
+	out[3] = (uint8_t)((in >> 32) & 0xFF);
+	out[4] = (uint8_t)((in >> 24) & 0xFF);
+	out[5] = (uint8_t)((in >> 16) & 0xFF);
+	out[6] = (uint8_t)((in >>  8) & 0xFF);
+	out[7] = (uint8_t)((in >>  0) & 0xFF);
+	return 8;
+}
+
+static inline uint64_t uint64be_decode(uint8_t *in) {
+	return (((uint64_t)(in[0])) << 56)
+	     | (((uint64_t)(in[1])) << 48)
+	     | (((uint64_t)(in[2])) << 40)
+	     | (((uint64_t)(in[3])) << 32)
+	     | (((uint64_t)(in[4])) << 24)
+	     | (((uint64_t)(in[5])) << 16)
+	     | (((uint64_t)(in[6])) <<  8)
+	     | (((uint64_t)(in[7])) <<  0)
+	     ;
+}
+
+static inline uint64be_t uint64be_marshal(uint64_t in) {
+	uint64be_t out;
+	uint64be_encode(out.octets, in);
+	return out;
+}
+
+static inline uint64_t uint64be_unmarshal(uint64be_t in) {
+	return uint64be_decode(in.octets);
+}
+
 /* Little endian **************************************************************/
 
 typedef struct {
@@ -131,4 +170,43 @@ static inline uint32_t uint32le_unmarshal(uint32le_t in) {
 	return uint32le_decode(in.octets);
 }
 
+typedef struct {
+	uint8_t octets[8];
+} uint64le_t;
+static_assert(sizeof(uint64le_t) == 8);
+
+static inline size_t uint64le_encode(uint8_t *out, uint64_t in) {
+	out[0] = (uint8_t)((in >>  0) & 0xFF);
+	out[1] = (uint8_t)((in >>  8) & 0xFF);
+	out[2] = (uint8_t)((in >> 16) & 0xFF);
+	out[3] = (uint8_t)((in >> 24) & 0xFF);
+	out[4] = (uint8_t)((in >> 32) & 0xFF);
+	out[5] = (uint8_t)((in >> 40) & 0xFF);
+	out[6] = (uint8_t)((in >> 48) & 0xFF);
+	out[7] = (uint8_t)((in >> 56) & 0xFF);
+	return 8;
+}
+
+static inline uint64_t uint64le_decode(uint8_t *in) {
+	return (((uint64_t)(in[0])) <<  0)
+	     | (((uint64_t)(in[1])) <<  8)
+	     | (((uint64_t)(in[2])) << 16)
+	     | (((uint64_t)(in[3])) << 24)
+	     | (((uint64_t)(in[4])) << 32)
+	     | (((uint64_t)(in[5])) << 40)
+	     | (((uint64_t)(in[6])) << 48)
+	     | (((uint64_t)(in[7])) << 56)
+	     ;
+}
+
+static inline uint64le_t uint64le_marshal(uint64_t in) {
+	uint64le_t out;
+	uint64le_encode(out.octets, in);
+	return out;
+}
+
+static inline uint64_t uint64le_unmarshal(uint64le_t in) {
+	return uint64le_decode(in.octets);
+}
+
 #endif /* _LIBMISC_ENDIAN_H_ */
diff --git a/libmisc/tests/test_endian.c b/libmisc/tests/test_endian.c
index d0b547c..dcb3cc2 100644
--- a/libmisc/tests/test_endian.c
+++ b/libmisc/tests/test_endian.c
@@ -1,6 +1,6 @@
 /* libmisc/tests/test_endian.c - Tests for <libmisc/endian.h>
  *
- * Copyright (C) 2024  Luke T. Shumaker <lukeshu@lukeshu.com>
+ * Copyright (C) 2024-2025  Luke T. Shumaker <lukeshu@lukeshu.com>
  * SPDX-License-Identifier: AGPL-3.0-or-later
  */
 
@@ -11,22 +11,31 @@
 #include "test.h"
 
 int main() {
-	uint8_t act[12] = {0};
-	uint16be_encode(&act[0], UINT16_C(0x1234));
-	uint32be_encode(&act[2], UINT32_C(0x56789ABC));
-	uint16le_encode(&act[6], UINT16_C(0x1234));
-	uint32le_encode(&act[8], UINT32_C(0x56789ABC));
+	uint8_t act[(2+4+8)*2] = {0};
+	size_t pos = 0;
+	pos += uint16be_encode(&act[pos], UINT16_C(0x1234));
+	pos += uint32be_encode(&act[pos], UINT32_C(0x56789ABC));
+	pos += uint64be_encode(&act[pos], UINT64_C(0xAC589A93278CB30A));
+	pos += uint16le_encode(&act[pos], UINT16_C(0x1234));
+	pos += uint32le_encode(&act[pos], UINT32_C(0x56789ABC));
+	pos += uint64le_encode(&act[pos], UINT64_C(0xAC589A93278CB30A));
 
-	uint8_t exp[12] = { 0x12, 0x34,
-	                    0x56, 0x78, 0x9A, 0xBC,
-	                    0x34, 0x12,
-	                    0xBC, 0x9A, 0x78, 0x56 };
-	test_assert(memcmp(act, exp, 12) == 0);
+	test_assert(pos == sizeof(act));
+	uint8_t exp[(2+4+8)*2] = { 0x12, 0x34,
+	                           0x56, 0x78, 0x9A, 0xBC,
+	                           0xAC, 0x58, 0x9A, 0x93, 0x27, 0x8C, 0xB3, 0x0A,
+	                           0x34, 0x12,
+	                           0xBC, 0x9A, 0x78, 0x56,
+	                           0x0A, 0xB3, 0x8C, 0x27, 0x93, 0x9A, 0x58, 0xAC};
+	test_assert(memcmp(act, exp, sizeof(act)) == 0);
 
-	test_assert(uint16be_decode(&act[0]) == UINT16_C(0x1234));
-	test_assert(uint32be_decode(&act[2]) == UINT32_C(0x56789ABC));
-	test_assert(uint16le_decode(&act[6]) == UINT16_C(0x1234));
-	test_assert(uint32le_decode(&act[8]) == UINT32_C(0x56789ABC));
+	pos = 0;
+	test_assert(uint16be_decode(&act[pos]) == UINT16_C(0x1234)); pos += 2;
+	test_assert(uint32be_decode(&act[pos]) == UINT32_C(0x56789ABC)); pos += 4;
+	test_assert(uint64be_decode(&act[pos]) == UINT64_C(0xAC589A93278CB30A)); pos += 8;
+	test_assert(uint16le_decode(&act[pos]) == UINT16_C(0x1234)); pos += 2;
+	test_assert(uint32le_decode(&act[pos]) == UINT32_C(0x56789ABC)); pos += 4;
+	test_assert(uint64le_decode(&act[pos]) == UINT64_C(0xAC589A93278CB30A)); pos += 8;
 
 	return 0;
 }