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Posted to commits@mynewt.apache.org by pa...@apache.org on 2016/09/14 20:32:48 UTC
[02/10] incubator-mynewt-core git commit: Add tinycbor and iotivity
constrained to the repo.
http://git-wip-us.apache.org/repos/asf/incubator-mynewt-core/blob/ece29bb3/libs/tinycbor/src/cbortojson.c
----------------------------------------------------------------------
diff --git a/libs/tinycbor/src/cbortojson.c b/libs/tinycbor/src/cbortojson.c
new file mode 100644
index 0000000..953f2aa
--- /dev/null
+++ b/libs/tinycbor/src/cbortojson.c
@@ -0,0 +1,686 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 Intel Corporation
+**
+** 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.
+**
+****************************************************************************/
+
+#define _BSD_SOURCE 1
+#define _DEFAULT_SOURCE 1
+#define _GNU_SOURCE 1
+#define _POSIX_C_SOURCE 200809L
+#ifndef __STDC_LIMIT_MACROS
+# define __STDC_LIMIT_MACROS 1
+#endif
+
+#include "cbor.h"
+#include "cborjson.h"
+#include "compilersupport_p.h"
+#include "math_support_p.h"
+
+#include <float.h>
+#include <inttypes.h>
+#include <math.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+
+/**
+ * \defgroup CborToJson Converting CBOR to JSON
+ * \brief Group of functions used to convert CBOR to JSON.
+ *
+ * This group contains two functions that are can be used to convert one
+ * CborValue object to an equivalent JSON representation. This module attempts
+ * to follow the recommendations from RFC 7049 section 4.1 "Converting from
+ * CBOR to JSON", though it has a few differences. They are noted below.
+ *
+ * These functions produce a "minified" JSON output, with no spacing,
+ * indentation or line breaks. If those are necessary, they need to be applied
+ * in a post-processing phase.
+ *
+ * Note that JSON cannot support all CBOR types with fidelity, so the
+ * conversion is usually lossy. For that reason, TinyCBOR supports adding a set
+ * of metadata JSON values that can be used by a JSON-to-CBOR converter to
+ * restore the original data types.
+ *
+ * The TinyCBOR library does not provide a way to convert from JSON
+ * representation back to encoded form. However, it provides a tool called
+ * \c json2cbor which can be used for that purpose. That tool supports the
+ * metadata format that these functions may produce.
+ *
+ * Either of the functions in this section will attempt to convert exactly one
+ * CborValue object to JSON. Those functions may return any error documented
+ * for the functions for CborParsing. In addition, if the C standard library
+ * stream functions return with error, the text conversion will return with
+ * error CborErrorIO.
+ *
+ * These functions also perform UTF-8 validation in CBOR text strings. If they
+ * encounter a sequence of bytes that not permitted in UTF-8, they will return
+ * CborErrorInvalidUtf8TextString. That includes encoding of surrogate points
+ * in UTF-8.
+ *
+ * \warning The metadata produced by these functions is not guaranteed to
+ * remain stable. A future update of TinyCBOR may produce different output for
+ * the same input and parsers may be unable to handle them.
+ *
+ * \sa CborParsing, CborPretty, cbor_parser_init()
+ */
+
+/**
+ * \addtogroup CborToJson
+ * @{
+ * <h2 class="groupheader">Conversion limitations</h2>
+ *
+ * When converting from CBOR to JSON, there may be information loss. This
+ * section lists the possible scenarios.
+ *
+ * \par Number precision:
+ * ALL JSON numbers, due to its JavaScript heritage, are IEEE 754
+ * double-precision floating point. This means JSON is not capable of
+ * representing integers numbers outside the range [-(2<sup>53</sup>)+1,
+ * 2<sup>53</sup>-1] and is not capable of representing NaN or infinite. If the
+ * CBOR data contains a number outside the valid range, the conversion will
+ * lose precision. If the input was NaN or infinite, the result of the
+ * conversion will be "null". In addition, the distinction between half-,
+ * single- and double-precision is lost.
+ *
+ * \par
+ * If enabled, the original value and original type are stored in the metadata.
+ *
+ * \par Non-native types:
+ * CBOR's type system is richer than JSON's, which means some data values
+ * cannot be represented when converted to JSON. The conversion silently turns
+ * them into strings: CBOR simple types become "simple(nn)" where \c nn is the
+ * simple type's value, with the exception of CBOR undefined, which becomes
+ * "undefined", while CBOR byte strings are converted to an Base16, Base64, or
+ * Base64url encoding
+ *
+ * \par
+ * If enabled, the original type is stored in the metadata.
+ *
+ * \par Presence of tags:
+ * JSON has no support for tagged values, so by default tags are dropped when
+ * converting to JSON. However, if the CborConvertObeyByteStringTags option is
+ * active (default), then certain known tags are honored and are used to format
+ * the conversion of the tagged byte string to JSON.
+ *
+ * \par
+ * If the CborConvertTagsToObjects option is active, then the tag and the
+ * tagged value are converted to to a JSON object. Otherwise, if enabled, the
+ * last (innermost) tag is stored in the metadata.
+ *
+ * \par Non-string keys in maps:
+ * JSON requires all Object keys to be strings, while CBOR does not. By
+ * default, if a non-string key is found, the conversion fails with error
+ * CborErrorJsonObjectKeyNotString. If the CborConvertStringifyMapKeys option
+ * is active, then the conversion attempts to create a string representation
+ * using CborPretty. Note that the \c json2cbor tool is not able to parse this
+ * back to the original form.
+ *
+ * \par Duplicate keys in maps:
+ * Neither JSON nor CBOR allow duplicated keys, but current TinyCBOR does not
+ * validate that this is the case. If there are duplicated keys in the input,
+ * they will be repeated in the output, which may JSON tools may flag as
+ * invalid. In addition to that, if the CborConvertStringifyMapKeys option is
+ * active, it is possible that a non-string key in a CBOR map will be converted
+ * to a string form that is identical to another key.
+ *
+ * \par
+ * When metadata support is active, the conversion will add extra key-value
+ * pairs to the JSON output so it can store the metadata. It is possible that
+ * the keys for the metadata clash with existing keys in the JSON map.
+ */
+
+extern FILE *open_memstream(char **bufptr, size_t *sizeptr);
+
+enum ConversionStatusFlags {
+ TypeWasNotNative = 0x100, /* anything but strings, boolean, null, arrays and maps */
+ TypeWasTagged = 0x200,
+ NumberPrecisionWasLost = 0x400,
+ NumberWasNaN = 0x800,
+ NumberWasInfinite = 0x1000,
+ NumberWasNegative = 0x2000, /* always used with NumberWasInifite or NumberWasTooBig */
+
+ FinalTypeMask = 0xff
+};
+
+typedef struct ConversionStatus {
+ CborTag lastTag;
+ uint64_t originalNumber;
+ int flags;
+} ConversionStatus;
+
+static CborError value_to_json(FILE *out, CborValue *it, int flags, CborType type, ConversionStatus *status);
+
+static CborError dump_bytestring_base16(char **result, CborValue *it)
+{
+ static const char characters[] = "0123456789abcdef";
+ size_t i;
+ size_t n = 0;
+ uint8_t *buffer;
+ CborError err = cbor_value_calculate_string_length(it, &n);
+ if (err)
+ return err;
+
+ /* a Base16 (hex) output is twice as big as our buffer */
+ buffer = (uint8_t *)malloc(n * 2 + 1);
+ *result = (char *)buffer;
+
+ /* let cbor_value_copy_byte_string know we have an extra byte for the terminating NUL */
+ ++n;
+ err = cbor_value_copy_byte_string(it, buffer + n - 1, &n, it);
+ assert(err == CborNoError);
+
+ for (i = 0; i < n; ++i) {
+ uint8_t byte = buffer[n + i];
+ buffer[2*i] = characters[byte >> 4];
+ buffer[2*i + 1] = characters[byte & 0xf];
+ }
+ return CborNoError;
+}
+
+static CborError generic_dump_base64(char **result, CborValue *it, const char alphabet[65])
+{
+ size_t n = 0, i;
+ uint8_t *buffer, *out, *in;
+ CborError err = cbor_value_calculate_string_length(it, &n);
+ if (err)
+ return err;
+
+ /* a Base64 output (untruncated) has 4 bytes for every 3 in the input */
+ size_t len = (n + 5) / 3 * 4;
+ out = buffer = (uint8_t *)malloc(len + 1);
+ *result = (char *)buffer;
+
+ /* we read our byte string at the tail end of the buffer
+ * so we can do an in-place conversion while iterating forwards */
+ in = buffer + len - n;
+
+ /* let cbor_value_copy_byte_string know we have an extra byte for the terminating NUL */
+ ++n;
+ err = cbor_value_copy_byte_string(it, in, &n, it);
+ assert(err == CborNoError);
+
+ uint_least32_t val = 0;
+ for (i = 0; n - i >= 3; i += 3) {
+ /* read 3 bytes x 8 bits = 24 bits */
+ if (false) {
+#ifdef __GNUC__
+ } else if (i) {
+ __builtin_memcpy(&val, in + i - 1, sizeof(val));
+ val = cbor_ntohl(val);
+#endif
+ } else {
+ val = (in[i] << 16) | (in[i + 1] << 8) | in[i + 2];
+ }
+
+ /* write 4 chars x 6 bits = 24 bits */
+ *out++ = alphabet[(val >> 18) & 0x3f];
+ *out++ = alphabet[(val >> 12) & 0x3f];
+ *out++ = alphabet[(val >> 6) & 0x3f];
+ *out++ = alphabet[val & 0x3f];
+ }
+
+ /* maybe 1 or 2 bytes left */
+ if (n - i) {
+ /* we can read in[i + 1] even if it's past the end of the string because
+ * we know (by construction) that it's a NUL byte */
+#ifdef __GNUC__
+ uint16_t val16;
+ __builtin_memcpy(&val16, in + i, sizeof(val16));
+ val = cbor_ntohs(val16);
+#else
+ val = (in[i] << 8) | in[i + 1];
+#endif
+ val <<= 8;
+
+ /* the 65th character in the alphabet is our filler: either '=' or '\0' */
+ out[4] = '\0';
+ out[3] = alphabet[64];
+ if (n - i == 2) {
+ /* write the third char in 3 chars x 6 bits = 18 bits */
+ out[2] = alphabet[(val >> 6) & 0x3f];
+ } else {
+ out[2] = alphabet[64]; /* filler */
+ }
+ out[1] = alphabet[(val >> 12) & 0x3f];
+ out[0] = alphabet[(val >> 18) & 0x3f];
+ } else {
+ out[0] = '\0';
+ }
+
+ return CborNoError;
+}
+
+static CborError dump_bytestring_base64(char **result, CborValue *it)
+{
+ static const char alphabet[] = "ABCDEFGH" "IJKLMNOP" "QRSTUVWX" "YZabcdef"
+ "ghijklmn" "opqrstuv" "wxyz0123" "456789+/" "=";
+ return generic_dump_base64(result, it, alphabet);
+}
+
+static CborError dump_bytestring_base64url(char **result, CborValue *it)
+{
+ static const char alphabet[] = "ABCDEFGH" "IJKLMNOP" "QRSTUVWX" "YZabcdef"
+ "ghijklmn" "opqrstuv" "wxyz0123" "456789-_";
+ return generic_dump_base64(result, it, alphabet);
+}
+
+static CborError add_value_metadata(FILE *out, CborType type, const ConversionStatus *status)
+{
+ int flags = status->flags;
+ if (flags & TypeWasTagged) {
+ /* extract the tagged type, which may be JSON native */
+ type = flags & FinalTypeMask;
+ flags &= ~(FinalTypeMask | TypeWasTagged);
+
+ if (fprintf(out, "\"tag\":\"%" PRIu64 "\"%s", status->lastTag,
+ flags & ~TypeWasTagged ? "," : "") < 0)
+ return CborErrorIO;
+ }
+
+ if (!flags)
+ return CborNoError;
+
+ /* print at least the type */
+ if (fprintf(out, "\"t\":%d", type) < 0)
+ return CborErrorIO;
+
+ if (flags & NumberWasNaN)
+ if (fprintf(out, ",\"v\":\"nan\"") < 0)
+ return CborErrorIO;
+ if (flags & NumberWasInfinite)
+ if (fprintf(out, ",\"v\":\"%sinf\"", flags & NumberWasNegative ? "-" : "") < 0)
+ return CborErrorIO;
+ if (flags & NumberPrecisionWasLost)
+ if (fprintf(out, ",\"v\":\"%c%" PRIx64 "\"", flags & NumberWasNegative ? '-' : '+',
+ status->originalNumber) < 0)
+ return CborErrorIO;
+ if (type == CborSimpleType)
+ if (fprintf(out, ",\"v\":%d", (int)status->originalNumber) < 0)
+ return CborErrorIO;
+ return CborNoError;
+}
+
+static CborError find_tagged_type(CborValue *it, CborTag *tag, CborType *type)
+{
+ CborError err = CborNoError;
+ *type = cbor_value_get_type(it);
+ while (*type == CborTagType) {
+ cbor_value_get_tag(it, tag); /* can't fail */
+ err = cbor_value_advance_fixed(it);
+ if (err)
+ return err;
+
+ *type = cbor_value_get_type(it);
+ }
+ return err;
+}
+
+static CborError tagged_value_to_json(FILE *out, CborValue *it, int flags, ConversionStatus *status)
+{
+ CborTag tag;
+ CborError err;
+
+ if (flags & CborConvertTagsToObjects) {
+ cbor_value_get_tag(it, &tag); /* can't fail */
+ err = cbor_value_advance_fixed(it);
+ if (err)
+ return err;
+
+ if (fprintf(out, "{\"tag%" PRIu64 "\":", tag) < 0)
+ return CborErrorIO;
+
+ CborType type = cbor_value_get_type(it);
+ err = value_to_json(out, it, flags, type, status);
+ if (err)
+ return err;
+ if (flags & CborConvertAddMetadata && status->flags) {
+ if (fprintf(out, ",\"tag%" PRIu64 "$cbor\":{", tag) < 0 ||
+ add_value_metadata(out, type, status) != CborNoError ||
+ fputc('}', out) < 0)
+ return CborErrorIO;
+ }
+ if (fputc('}', out) < 0)
+ return CborErrorIO;
+ status->flags = TypeWasNotNative | CborTagType;
+ return CborNoError;
+ }
+
+ CborType type;
+ err = find_tagged_type(it, &status->lastTag, &type);
+ if (err)
+ return err;
+ tag = status->lastTag;
+
+ /* special handling of byte strings? */
+ if (type == CborByteStringType && (flags & CborConvertByteStringsToBase64Url) == 0 &&
+ (tag == CborNegativeBignumTag || tag == CborExpectedBase16Tag || tag == CborExpectedBase64Tag)) {
+ char *str;
+ char *pre = "";
+
+ if (tag == CborNegativeBignumTag) {
+ pre = "~";
+ err = dump_bytestring_base64url(&str, it);
+ } else if (tag == CborExpectedBase64Tag) {
+ err = dump_bytestring_base64(&str, it);
+ } else { /* tag == CborExpectedBase16Tag */
+ err = dump_bytestring_base16(&str, it);
+ }
+ if (err)
+ return err;
+ err = fprintf(out, "\"%s%s\"", pre, str) < 0 ? CborErrorIO : CborNoError;
+ free(str);
+ status->flags = TypeWasNotNative | TypeWasTagged | CborByteStringType;
+ return err;
+ }
+
+ /* no special handling */
+ err = value_to_json(out, it, flags, type, status);
+ status->flags |= TypeWasTagged | type;
+ return err;
+}
+
+static CborError stringify_map_key(char **key, CborValue *it, int flags, CborType type)
+{
+ (void)flags; /* unused */
+ (void)type; /* unused */
+#ifdef WITHOUT_OPEN_MEMSTREAM
+ (void)key; /* unused */
+ (void)it; /* unused */
+ return CborErrorJsonNotImplemented;
+#else
+ size_t size;
+
+ FILE *memstream = open_memstream(key, &size);
+ if (memstream == NULL)
+ return CborErrorOutOfMemory; /* could also be EMFILE, but it's unlikely */
+ CborError err = cbor_value_to_pretty_advance(memstream, it);
+
+ if (unlikely(fclose(memstream) < 0 || *key == NULL))
+ return CborErrorInternalError;
+ return err;
+#endif
+}
+
+static CborError array_to_json(FILE *out, CborValue *it, int flags, ConversionStatus *status)
+{
+ const char *comma = "";
+ while (!cbor_value_at_end(it)) {
+ if (fprintf(out, "%s", comma) < 0)
+ return CborErrorIO;
+ comma = ",";
+
+ CborError err = value_to_json(out, it, flags, cbor_value_get_type(it), status);
+ if (err)
+ return err;
+ }
+ return CborNoError;
+}
+
+static CborError map_to_json(FILE *out, CborValue *it, int flags, ConversionStatus *status)
+{
+ const char *comma = "";
+ CborError err;
+ while (!cbor_value_at_end(it)) {
+ char *key;
+ if (fprintf(out, "%s", comma) < 0)
+ return CborErrorIO;
+ comma = ",";
+
+ CborType keyType = cbor_value_get_type(it);
+ if (likely(keyType == CborTextStringType)) {
+ size_t n = 0;
+ err = cbor_value_dup_text_string(it, &key, &n, it);
+ } else if (flags & CborConvertStringifyMapKeys) {
+ err = stringify_map_key(&key, it, flags, keyType);
+ } else {
+ return CborErrorJsonObjectKeyNotString;
+ }
+ if (err)
+ return err;
+
+ /* first, print the key */
+ if (fprintf(out, "\"%s\":", key) < 0)
+ return CborErrorIO;
+
+ /* then, print the value */
+ CborType valueType = cbor_value_get_type(it);
+ err = value_to_json(out, it, flags, valueType, status);
+
+ /* finally, print any metadata we may have */
+ if (flags & CborConvertAddMetadata) {
+ if (!err && keyType != CborTextStringType) {
+ if (fprintf(out, ",\"%s$keycbordump\":true", key) < 0)
+ err = CborErrorIO;
+ }
+ if (!err && status->flags) {
+ if (fprintf(out, ",\"%s$cbor\":{", key) < 0 ||
+ add_value_metadata(out, valueType, status) != CborNoError ||
+ fputc('}', out) < 0)
+ err = CborErrorIO;
+ }
+ }
+
+ free(key);
+ if (err)
+ return err;
+ }
+ return CborNoError;
+}
+
+static CborError value_to_json(FILE *out, CborValue *it, int flags, CborType type, ConversionStatus *status)
+{
+ CborError err;
+ status->flags = 0;
+
+ switch (type) {
+ case CborArrayType:
+ case CborMapType: {
+ /* recursive type */
+ CborValue recursed;
+ err = cbor_value_enter_container(it, &recursed);
+ if (err) {
+ it->ptr = recursed.ptr;
+ return err; /* parse error */
+ }
+ if (fputc(type == CborArrayType ? '[' : '{', out) < 0)
+ return CborErrorIO;
+
+ err = (type == CborArrayType) ?
+ array_to_json(out, &recursed, flags, status) :
+ map_to_json(out, &recursed, flags, status);
+ if (err) {
+ it->ptr = recursed.ptr;
+ return err; /* parse error */
+ }
+
+ if (fputc(type == CborArrayType ? ']' : '}', out) < 0)
+ return CborErrorIO;
+ err = cbor_value_leave_container(it, &recursed);
+ if (err)
+ return err; /* parse error */
+
+ status->flags = 0; /* reset, there are never conversion errors for us */
+ return CborNoError;
+ }
+
+ case CborIntegerType: {
+ double num; /* JS numbers are IEEE double precision */
+ uint64_t val;
+ cbor_value_get_raw_integer(it, &val); /* can't fail */
+ num = (double)val;
+
+ if (cbor_value_is_negative_integer(it)) {
+ num = -num - 1; /* convert to negative */
+ if ((uint64_t)(-num - 1) != val) {
+ status->flags = NumberPrecisionWasLost | NumberWasNegative;
+ status->originalNumber = val;
+ }
+ } else {
+ if ((uint64_t)num != val) {
+ status->flags = NumberPrecisionWasLost;
+ status->originalNumber = val;
+ }
+ }
+ if (fprintf(out, "%.0f", num) < 0) /* this number has no fraction, so no decimal points please */
+ return CborErrorIO;
+ break;
+ }
+
+ case CborByteStringType:
+ case CborTextStringType: {
+ char *str;
+ if (type == CborByteStringType) {
+ err = dump_bytestring_base64url(&str, it);
+ status->flags = TypeWasNotNative;
+ } else {
+ size_t n = 0;
+ err = cbor_value_dup_text_string(it, &str, &n, it);
+ }
+ if (err)
+ return err;
+ err = (fprintf(out, "\"%s\"", str) < 0) ? CborErrorIO : CborNoError;
+ free(str);
+ return err;
+ }
+
+ case CborTagType:
+ return tagged_value_to_json(out, it, flags, status);
+
+ case CborSimpleType: {
+ uint8_t simple_type;
+ cbor_value_get_simple_type(it, &simple_type); /* can't fail */
+ status->flags = TypeWasNotNative;
+ status->originalNumber = simple_type;
+ if (fprintf(out, "\"simple(%" PRIu8 ")\"", simple_type) < 0)
+ return CborErrorIO;
+ break;
+ }
+
+ case CborNullType:
+ if (fprintf(out, "null") < 0)
+ return CborErrorIO;
+ break;
+
+ case CborUndefinedType:
+ status->flags = TypeWasNotNative;
+ if (fprintf(out, "\"undefined\"") < 0)
+ return CborErrorIO;
+ break;
+
+ case CborBooleanType: {
+ bool val;
+ cbor_value_get_boolean(it, &val); /* can't fail */
+ if (fprintf(out, val ? "true" : "false") < 0)
+ return CborErrorIO;
+ break;
+ }
+
+ case CborDoubleType: {
+ double val;
+ if (false) {
+ float f;
+ case CborFloatType:
+ status->flags = TypeWasNotNative;
+ cbor_value_get_float(it, &f);
+ val = f;
+ } else if (false) {
+ uint16_t f16;
+ case CborHalfFloatType:
+ status->flags = TypeWasNotNative;
+ cbor_value_get_half_float(it, &f16);
+ val = decode_half(f16);
+ } else {
+ cbor_value_get_double(it, &val);
+ }
+
+ int r = fpclassify(val);
+ if (r == FP_NAN || r == FP_INFINITE) {
+ if (fprintf(out, "null") < 0)
+ return CborErrorIO;
+ status->flags |= r == FP_NAN ? NumberWasNaN :
+ NumberWasInfinite | (val < 0 ? NumberWasNegative : 0);
+ } else {
+ uint64_t ival = (uint64_t)fabs(val);
+ if ((double)ival == fabs(val)) {
+ /* print as integer so we get the full precision */
+ r = fprintf(out, "%s%" PRIu64, val < 0 ? "-" : "", ival);
+ status->flags |= TypeWasNotNative; /* mark this integer number as a double */
+ } else {
+ /* this number is definitely not a 64-bit integer */
+ r = fprintf(out, "%." DBL_DECIMAL_DIG_STR "g", val);
+ }
+ if (r < 0)
+ return CborErrorIO;
+ }
+ break;
+ }
+
+ case CborInvalidType:
+ return CborErrorUnknownType;
+ }
+
+ return cbor_value_advance_fixed(it);
+}
+
+/**
+ * \enum CborToJsonFlags
+ * The CborToJsonFlags enum contains flags that control the conversion of CBOR to JSON.
+ *
+ * \value CborConvertAddMetadata Adds metadata to facilitate restoration of the original CBOR data.
+ * \value CborConvertTagsToObjects Converts CBOR tags to JSON objects
+ * \value CborConvertIgnoreTags (default) Ignore CBOR tags, except for byte strings
+ * \value CborConvertObeyByteStringTags (default) Honor formatting of CBOR byte strings if so tagged
+ * \value CborConvertByteStringsToBase64Url Force the conversion of all CBOR byte strings to Base64url encoding, despite any tags
+ * \value CborConvertRequireMapStringKeys (default) Require CBOR map keys to be strings, failing the conversion if they are not
+ * \value CborConvertStringifyMapKeys Convert non-string keys in CBOR maps to a string form
+ * \value CborConvertDefaultFlags Default conversion flags.
+ */
+
+/**
+ * \fn CborError cbor_value_to_json(FILE *out, const CborValue *value, int flags)
+ *
+ * Converts the current CBOR type pointed by \a value to JSON and writes that
+ * to the \a out stream. If an error occurs, this function returns an error
+ * code similar to CborParsing. The \a flags parameter indicates one of the
+ * flags from CborToJsonFlags that control the conversion.
+ *
+ * \sa cbor_value_to_json_advance(), cbor_value_to_pretty()
+ */
+
+/**
+ * Converts the current CBOR type pointed by \a value to JSON and writes that
+ * to the \a out stream. If an error occurs, this function returns an error
+ * code similar to CborParsing. The \a flags parameter indicates one of the
+ * flags from CborToJsonFlags that control the conversion.
+ *
+ * If no error ocurred, this function advances \a value to the next element.
+ *
+ * \sa cbor_value_to_json(), cbor_value_to_pretty_advance()
+ */
+CborError cbor_value_to_json_advance(FILE *out, CborValue *value, int flags)
+{
+ ConversionStatus status;
+ return value_to_json(out, value, flags, cbor_value_get_type(value), &status);
+}
+
+/** @} */
http://git-wip-us.apache.org/repos/asf/incubator-mynewt-core/blob/ece29bb3/libs/tinycbor/src/open_memstream.c
----------------------------------------------------------------------
diff --git a/libs/tinycbor/src/open_memstream.c b/libs/tinycbor/src/open_memstream.c
new file mode 100644
index 0000000..eaa53e5
--- /dev/null
+++ b/libs/tinycbor/src/open_memstream.c
@@ -0,0 +1,117 @@
+/****************************************************************************
+**
+** Copyright (C) 2015 Intel Corporation
+**
+** 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.
+**
+****************************************************************************/
+
+#define _BSD_SOURCE 1
+#define _DEFAULT_SOURCE 1
+#define _GNU_SOURCE 1
+
+#ifndef WITHOUT_OPEN_MEMSTREAM
+
+#include <sys/types.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#if defined(__unix__) || defined(__APPLE__)
+# include <unistd.h>
+#endif
+#ifdef __APPLE__
+typedef int RetType;
+typedef int LenType;
+#elif __GLIBC__
+typedef ssize_t RetType;
+typedef size_t LenType;
+#else
+# error "Cannot implement open_memstream!"
+#endif
+
+#include "compilersupport_p.h"
+
+struct Buffer
+{
+ char **ptr;
+ size_t *len;
+ size_t alloc;
+};
+
+static RetType write_to_buffer(void *cookie, const char *data, LenType len)
+{
+ struct Buffer *b = (struct Buffer *)cookie;
+ char *ptr = *b->ptr;
+ size_t newsize;
+
+ errno = EFBIG;
+ if (unlikely(add_check_overflow(*b->len, len, &newsize)))
+ return -1;
+
+ if (newsize > b->alloc) {
+ // make room
+ size_t newalloc = newsize + newsize / 2 + 1; // give 50% more room
+ ptr = realloc(ptr, newalloc);
+ if (ptr == NULL)
+ return -1;
+ b->alloc = newalloc;
+ *b->ptr = ptr;
+ }
+
+ memcpy(ptr + *b->len, data, len);
+ *b->len = newsize;
+ return len;
+}
+
+static int close_buffer(void *cookie)
+{
+ struct Buffer *b = (struct Buffer *)cookie;
+ if (*b->ptr)
+ (*b->ptr)[*b->len] = '\0';
+ free(b);
+ return 0;
+}
+
+FILE *open_memstream(char **bufptr, size_t *lenptr)
+{
+ struct Buffer *b = (struct Buffer *)malloc(sizeof(struct Buffer));
+ if (b == NULL)
+ return NULL;
+ b->alloc = 0;
+ b->len = lenptr;
+ b->ptr = bufptr;
+ *bufptr = NULL;
+ *lenptr = 0;
+
+#ifdef __APPLE__
+ return funopen(b, NULL, write_to_buffer, NULL, close_buffer);
+#elif __GLIBC__
+ static const cookie_io_functions_t vtable = {
+ NULL,
+ write_to_buffer,
+ NULL,
+ close_buffer
+ };
+ return fopencookie(b, "w", vtable);
+#endif
+}
+
+#endif