core: Add generic LE/BE load/store uint type convertors and use them in msgb

Submitted-by: Max <max.suraev@fairwaves.co>
Signed-off-by: Sylvain Munaut <tnt@246tNt.com>

1 files changed, 103 insertions, 0 deletions

diff --git a/include/osmocom/core/bitXXgen.h.tpl b/include/osmocom/core/bitXXgen.h.tpl
new file mode 100644
index 00000000..35f26db7
--- /dev/null
+++ b/include/osmocom/core/bitXXgen.h.tpl
@@ -0,0 +1,103 @@
+/*
+ * bitXXgen.h
+ *
+ * Copyright (C) 2014  Max <max.suraev@fairwaves.co>
+ *
+ * All Rights Reserved
+ *
+ * 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; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#pragma once
+
+/*! \brief load unaligned n-byte integer (little-endian encoding) into uintXX_t
+ *  \param[in] p Buffer where integer is stored
+ *  \param[in] n Number of bytes stored in p
+ *  \returns XX bit unsigned integer
+ */
+static inline uintXX_t osmo_loadXXle_ext(const void *p, uint8_t n)
+{
+	uint8_t i;
+	uintXX_t r = 0;
+	const uint8_t *q = (uint8_t *)p;
+	for(i = 0; i < n; r |= ((uintXX_t)q[i] << (8 * i)), i++);
+	return r;
+}
+
+/*! \brief load unaligned n-byte integer (big-endian encoding) into uintXX_t
+ *  \param[in] p Buffer where integer is stored
+ *  \param[in] n Number of bytes stored in p
+ *  \returns XX bit unsigned integer
+ */
+static inline uintXX_t osmo_loadXXbe_ext(const void *p, uint8_t n)
+{
+	uint8_t i;
+	uintXX_t r = 0;
+	const uint8_t *q = (uint8_t *)p;
+	for(i = 0; i < n; r |= ((uintXX_t)q[i] << (XX - 8* (1 + i))), i++);
+	return r;
+}
+
+
+/*! \brief store unaligned n-byte integer (little-endian encoding) into uintXX_t
+ *  \param[in] x unsigned XX bit integer
+ *  \param[out] p Buffer to store integer
+ *  \param[in] n Number of bytes to store
+ */
+static inline void osmo_storeXXle_ext(uintXX_t x, uint8_t *p, uint8_t n)
+{
+	uint8_t i;
+	for(i = 0; i < n; p[i] = (x >> i * 8) & 0xFF, i++);
+}
+
+/*! \brief store unaligned n-byte integer (big-endian encoding) into uintXX_t
+ *  \param[in] x unsigned XX bit integer
+ *  \param[out] p Buffer to store integer
+ *  \param[in] n Number of bytes to store
+ */
+static inline void osmo_storeXXbe_ext(uintXX_t x, uint8_t *p, uint8_t n)
+{
+	uint8_t i;
+	for(i = 0; i < n; p[i] = (x >> ((n - 1 - i) * 8)) & 0xFF, i++);
+}
+
+
+/* Convenience function for most-used cases */
+
+
+/*! \brief load unaligned XX-bit integer (little-endian encoding) */
+static inline uintXX_t osmo_loadXXle(const void *p)
+{
+	return osmo_loadXXle_ext(p, XX / 8);
+}
+
+/*! \brief load unaligned XX-bit integer (big-endian encoding) */
+static inline uintXX_t osmo_loadXXbe(const void *p)
+{
+	return osmo_loadXXbe_ext(p, XX / 8);
+}
+
+
+/*! \brief store unaligned XX-bit integer (little-endian encoding) */
+static inline void osmo_storeXXle(uintXX_t x, void *p)
+{
+	return osmo_storeXXle_ext(x, p, XX / 8);
+}
+
+/*! \brief store unaligned XX-bit integer (big-endian encoding) */
+static inline void osmo_storeXXbe(uintXX_t x, void *p)
+{
+	return osmo_storeXXbe_ext(x, p, XX / 8);
+}