IDF release/v4.0 08219f3cf

tools/sdk/include/coap/coap2/encode.h

@@ -0,0 +1,96 @@
+/*
+ * encode.h -- encoding and decoding of CoAP data types
+ *
+ * Copyright (C) 2010-2012 Olaf Bergmann <bergmann@tzi.org>
+ *
+ * This file is part of the CoAP library libcoap. Please see README for terms
+ * of use.
+ */
+
+#ifndef COAP_ENCODE_H_
+#define COAP_ENCODE_H_
+
+#if (BSD >= 199103) || defined(WITH_CONTIKI) || defined(_WIN32)
+# include <string.h>
+#else
+# include <strings.h>
+#endif
+
+#include <stdint.h>
+
+#define Nn 8  /* duplicate definition of N if built on sky motes */
+#define ENCODE_HEADER_SIZE 4
+#define HIBIT (1 << (Nn - 1))
+#define EMASK ((1 << ENCODE_HEADER_SIZE) - 1)
+#define MMASK ((1 << Nn) - 1 - EMASK)
+#define MAX_VALUE ( (1 << Nn) - (1 << ENCODE_HEADER_SIZE) ) * (1 << ((1 << ENCODE_HEADER_SIZE) - 1))
+
+#define COAP_PSEUDOFP_DECODE_8_4(r) (r < HIBIT ? r : (r & MMASK) << (r & EMASK))
+
+#ifndef HAVE_FLS
+/* include this only if fls() is not available */
+extern int coap_fls(unsigned int i);
+#else
+#define coap_fls(i) fls(i)
+#endif
+
+#ifndef HAVE_FLSLL
+ /* include this only if flsll() is not available */
+extern int coap_flsll(long long i);
+#else
+#define coap_flsll(i) flsll(i)
+#endif
+
+/* ls and s must be integer variables */
+#define COAP_PSEUDOFP_ENCODE_8_4_DOWN(v,ls) (v < HIBIT ? v : (ls = coap_fls(v) - Nn, (v >> ls) & MMASK) + ls)
+#define COAP_PSEUDOFP_ENCODE_8_4_UP(v,ls,s) (v < HIBIT ? v : (ls = coap_fls(v) - Nn, (s = (((v + ((1<<ENCODE_HEADER_SIZE<<ls)-1)) >> ls) & MMASK)), s == 0 ? HIBIT + ls + 1 : s + ls))
+
+/**
+ * Decodes multiple-length byte sequences. @p buf points to an input byte
+ * sequence of length @p length. Returns the decoded value.
+ *
+ * @param buf The input byte sequence to decode from
+ * @param length The length of the input byte sequence
+ *
+ * @return      The decoded value
+ */
+unsigned int coap_decode_var_bytes(const uint8_t *buf, unsigned int length);
+
+/**
+ * Encodes multiple-length byte sequences. @p buf points to an output buffer of
+ * sufficient length to store the encoded bytes. @p value is the value to
+ * encode.
+ * Returns the number of bytes used to encode @p value or 0 on error.
+ *
+ * @param buf    The output buffer to decode into
+ * @param length The output buffer size to encode into (must be sufficient)
+ * @param value  The value to encode into the buffer
+ *
+ * @return       The number of bytes used to encode @p value or @c 0 on error.
+ */
+unsigned int coap_encode_var_safe(uint8_t *buf,
+                                  size_t length,
+                                  unsigned int value);
+
+/**
+ * @deprecated Use coap_encode_var_safe() instead.
+ * Provided for backward compatibility.  As @p value has a
+ * maximum value of 0xffffffff, and buf is usually defined as an array, it
+ * is unsafe to continue to use this variant if buf[] is less than buf[4].
+ *
+ * For example
+ *  char buf[1],oops;
+ *  ..
+ *  coap_encode_var_bytes(buf, 0xfff);
+ * would cause oops to get overwritten.  This error can only be found by code
+ * inspection.
+ *   coap_encode_var_safe(buf, sizeof(buf), 0xfff);
+ * would catch this error at run-time and should be used instead.
+ */
+COAP_STATIC_INLINE COAP_DEPRECATED int
+coap_encode_var_bytes(uint8_t *buf, unsigned int value
+) {
+  return (int)coap_encode_var_safe(buf, sizeof(value), value);
+}
+
+#endif /* COAP_ENCODE_H_ */