| /**************************************************************************** |
| ** |
| ** Copyright (C) 2021 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. |
| ** |
| ****************************************************************************/ |
| |
| #ifndef _BSD_SOURCE |
| #define _BSD_SOURCE 1 |
| #endif |
| #ifndef _DEFAULT_SOURCE |
| #define _DEFAULT_SOURCE 1 |
| #endif |
| #ifndef __STDC_LIMIT_MACROS |
| # define __STDC_LIMIT_MACROS 1 |
| #endif |
| |
| #include "cbor.h" |
| #include "cborinternal_p.h" |
| #include "compilersupport_p.h" |
| |
| #include <string.h> |
| |
| /** |
| * \defgroup CborParsing Parsing CBOR streams |
| * \brief Group of functions used to parse CBOR streams. |
| * |
| * TinyCBOR provides functions for pull-based stream parsing of a CBOR-encoded |
| * payload. The main data type for the parsing is a CborValue, which behaves |
| * like an iterator and can be used to extract the encoded data. It is first |
| * initialized with a call to cbor_parser_init() and is usually used to extract |
| * exactly one item, most often an array or map. |
| * |
| * Nested CborValue objects can be parsed using cbor_value_enter_container(). |
| * Each call to cbor_value_enter_container() must be matched by a call to |
| * cbor_value_leave_container(), with the exact same parameters. |
| * |
| * The example below initializes a CborParser object, begins the parsing with a |
| * CborValue and decodes a single integer: |
| * |
| * \code |
| * int extract_int(const uint8_t *buffer, size_t len) |
| * { |
| * CborParser parser; |
| * CborValue value; |
| * int result; |
| * cbor_parser_init(buffer, len, 0, &parser, &value); |
| * cbor_value_get_int(&value, &result); |
| * return result; |
| * } |
| * \endcode |
| * |
| * The code above does no error checking, which means it assumes the data comes |
| * from a source trusted to send one properly-encoded integer. The following |
| * example does the exact same operation, but includes error checking and |
| * returns 0 on parsing failure: |
| * |
| * \code |
| * int extract_int(const uint8_t *buffer, size_t len) |
| * { |
| * CborParser parser; |
| * CborValue value; |
| * int result; |
| * if (cbor_parser_init(buffer, len, 0, &parser, &value) != CborNoError) |
| * return 0; |
| * if (!cbor_value_is_integer(&value) || |
| * cbor_value_get_int(&value, &result) != CborNoError) |
| * return 0; |
| * return result; |
| * } |
| * \endcode |
| * |
| * Note, in the example above, that one can't distinguish a parsing failure |
| * from an encoded value of zero. Reporting a parsing error is left as an |
| * exercise to the reader. |
| * |
| * The code above does not execute a range-check either: it is possible that |
| * the value decoded from the CBOR stream encodes a number larger than what can |
| * be represented in a variable of type \c{int}. If detecting that case is |
| * important, the code should call cbor_value_get_int_checked() instead. |
| * |
| * <h3 class="groupheader">Memory and parsing constraints</h3> |
| * |
| * TinyCBOR is designed to run with little memory and with minimal overhead. |
| * Except where otherwise noted, the parser functions always run on constant |
| * time (O(1)), do not recurse and never allocate memory (thus, stack usage is |
| * bounded and is O(1)). |
| * |
| * <h3 class="groupheader">Error handling and preconditions</h3> |
| * |
| * All functions operating on a CborValue return a CborError condition, with |
| * CborNoError standing for the normal situation in which no parsing error |
| * occurred. All functions may return parsing errors in case the stream cannot |
| * be decoded properly, be it due to corrupted data or due to reaching the end |
| * of the input buffer. |
| * |
| * Error conditions must not be ignored. All decoder functions have undefined |
| * behavior if called after an error has been reported, and may crash. |
| * |
| * Some functions are also documented to have preconditions, like |
| * cbor_value_get_int() requiring that the input be an integral value. |
| * Violation of preconditions also results in undefined behavior and the |
| * program may crash. |
| */ |
| |
| /** |
| * \addtogroup CborParsing |
| * @{ |
| */ |
| |
| /** |
| * \struct CborValue |
| * |
| * This type contains one value parsed from the CBOR stream. Each CborValue |
| * behaves as an iterator in a StAX-style parser. |
| * |
| * \if privatedocs |
| * Implementation details: the CborValue contains these fields: |
| * \list |
| * \li ptr: pointer to the actual data |
| * \li flags: flags from the decoder |
| * \li extra: partially decoded integer value (0, 1 or 2 bytes) |
| * \li remaining: remaining items in this collection after this item or UINT32_MAX if length is unknown |
| * \endlist |
| * \endif |
| */ |
| |
| static uint64_t extract_number_and_advance(CborValue *it) |
| { |
| /* This function is only called after we've verified that the number |
| * here is valid, so we can just use _cbor_value_extract_int64_helper. */ |
| uint8_t descriptor; |
| uint64_t v = _cbor_value_extract_int64_helper(it); |
| |
| read_bytes_unchecked(it, &descriptor, 0, 1); |
| descriptor &= SmallValueMask; |
| |
| size_t bytesNeeded = descriptor < Value8Bit ? 0 : (1 << (descriptor - Value8Bit)); |
| advance_bytes(it, bytesNeeded + 1); |
| |
| return v; |
| } |
| |
| static bool is_fixed_type(uint8_t type) |
| { |
| return type != CborTextStringType && type != CborByteStringType && type != CborArrayType && |
| type != CborMapType; |
| } |
| |
| static CborError preparse_value(CborValue *it) |
| { |
| enum { |
| /* flags to keep */ |
| FlagsToKeep = CborIteratorFlag_ContainerIsMap | CborIteratorFlag_NextIsMapKey |
| }; |
| uint8_t descriptor; |
| |
| /* are we at the end? */ |
| it->type = CborInvalidType; |
| it->flags &= FlagsToKeep; |
| if (!read_bytes(it, &descriptor, 0, 1)) |
| return CborErrorUnexpectedEOF; |
| |
| uint8_t type = descriptor & MajorTypeMask; |
| it->type = type; |
| it->extra = (descriptor &= SmallValueMask); |
| |
| if (descriptor > Value64Bit) { |
| if (unlikely(descriptor != IndefiniteLength)) |
| return type == CborSimpleType ? CborErrorUnknownType : CborErrorIllegalNumber; |
| if (likely(!is_fixed_type(type))) { |
| /* special case */ |
| it->flags |= CborIteratorFlag_UnknownLength; |
| it->type = type; |
| return CborNoError; |
| } |
| return type == CborSimpleType ? CborErrorUnexpectedBreak : CborErrorIllegalNumber; |
| } |
| |
| size_t bytesNeeded = descriptor < Value8Bit ? 0 : (1 << (descriptor - Value8Bit)); |
| |
| if (bytesNeeded) { |
| if (!can_read_bytes(it, bytesNeeded + 1)) |
| return CborErrorUnexpectedEOF; |
| |
| it->extra = 0; |
| |
| /* read up to 16 bits into it->extra */ |
| if (bytesNeeded <= 2) { |
| read_bytes_unchecked(it, &it->extra, 1, bytesNeeded); |
| if (bytesNeeded == 2) |
| it->extra = cbor_ntohs(it->extra); |
| } else { |
| cbor_static_assert(CborIteratorFlag_IntegerValueTooLarge == (Value32Bit & 3)); |
| cbor_static_assert((CborIteratorFlag_IntegerValueIs64Bit | |
| CborIteratorFlag_IntegerValueTooLarge) == (Value64Bit & 3)); |
| it->flags |= (descriptor & 3); |
| } |
| } |
| |
| uint8_t majortype = type >> MajorTypeShift; |
| if (majortype == NegativeIntegerType) { |
| it->flags |= CborIteratorFlag_NegativeInteger; |
| it->type = CborIntegerType; |
| } else if (majortype == SimpleTypesType) { |
| switch (descriptor) { |
| case FalseValue: |
| it->extra = false; |
| it->type = CborBooleanType; |
| break; |
| |
| case SinglePrecisionFloat: |
| case DoublePrecisionFloat: |
| it->flags |= CborIteratorFlag_IntegerValueTooLarge; |
| /* fall through */ |
| case TrueValue: |
| case NullValue: |
| case UndefinedValue: |
| case HalfPrecisionFloat: |
| read_bytes_unchecked(it, &it->type, 0, 1); |
| break; |
| |
| case SimpleTypeInNextByte: |
| #ifndef CBOR_PARSER_NO_STRICT_CHECKS |
| if (unlikely(it->extra < 32)) { |
| it->type = CborInvalidType; |
| return CborErrorIllegalSimpleType; |
| } |
| #endif |
| break; |
| |
| case 28: |
| case 29: |
| case 30: |
| case Break: |
| cbor_assert(false); /* these conditions can't be reached */ |
| return CborErrorUnexpectedBreak; |
| } |
| } |
| |
| return CborNoError; |
| } |
| |
| static CborError preparse_next_value_nodecrement(CborValue *it) |
| { |
| uint8_t byte; |
| if (it->remaining == UINT32_MAX && read_bytes(it, &byte, 0, 1) && byte == (uint8_t)BreakByte) { |
| /* end of map or array */ |
| if ((it->flags & CborIteratorFlag_ContainerIsMap && it->flags & CborIteratorFlag_NextIsMapKey) |
| || it->type == CborTagType) { |
| /* but we weren't expecting it! */ |
| return CborErrorUnexpectedBreak; |
| } |
| it->type = CborInvalidType; |
| it->remaining = 0; |
| it->flags |= CborIteratorFlag_UnknownLength; /* leave_container must consume the Break */ |
| return CborNoError; |
| } |
| |
| return preparse_value(it); |
| } |
| |
| static CborError preparse_next_value(CborValue *it) |
| { |
| /* tags don't count towards item totals or whether we've successfully |
| * read a map's key or value */ |
| bool itemCounts = it->type != CborTagType; |
| |
| if (it->remaining != UINT32_MAX) { |
| if (itemCounts && --it->remaining == 0) { |
| it->type = CborInvalidType; |
| it->flags &= ~CborIteratorFlag_UnknownLength; /* no Break to consume */ |
| return CborNoError; |
| } |
| } |
| if (itemCounts) { |
| /* toggle the flag indicating whether this was a map key */ |
| it->flags ^= CborIteratorFlag_NextIsMapKey; |
| } |
| return preparse_next_value_nodecrement(it); |
| } |
| |
| static CborError advance_internal(CborValue *it) |
| { |
| uint64_t length = extract_number_and_advance(it); |
| |
| if (it->type == CborByteStringType || it->type == CborTextStringType) { |
| cbor_assert(length == (size_t)length); |
| cbor_assert((it->flags & CborIteratorFlag_UnknownLength) == 0); |
| advance_bytes(it, length); |
| } |
| |
| return preparse_next_value(it); |
| } |
| |
| /** \internal |
| * |
| * Decodes the CBOR integer value when it is larger than the 16 bits available |
| * in value->extra. This function requires that value->flags have the |
| * CborIteratorFlag_IntegerValueTooLarge flag set. |
| * |
| * This function is also used to extract single- and double-precision floating |
| * point values (SinglePrecisionFloat == Value32Bit and DoublePrecisionFloat == |
| * Value64Bit). |
| */ |
| uint64_t _cbor_value_decode_int64_internal(const CborValue *value) |
| { |
| cbor_assert(value->flags & CborIteratorFlag_IntegerValueTooLarge || |
| value->type == CborFloatType || value->type == CborDoubleType); |
| if (value->flags & CborIteratorFlag_IntegerValueIs64Bit) |
| return read_uint64(value, 1); |
| |
| return read_uint32(value, 1); |
| } |
| |
| /** |
| * Initializes the CBOR parser for parsing \a size bytes beginning at \a |
| * buffer. Parsing will use flags set in \a flags. The iterator to the first |
| * element is returned in \a it. |
| * |
| * The \a parser structure needs to remain valid throughout the decoding |
| * process. It is not thread-safe to share one CborParser among multiple |
| * threads iterating at the same time, but the object can be copied so multiple |
| * threads can iterate. |
| */ |
| CborError cbor_parser_init(const uint8_t *buffer, size_t size, uint32_t flags, CborParser *parser, CborValue *it) |
| { |
| memset(parser, 0, sizeof(*parser)); |
| parser->source.end = buffer + size; |
| parser->flags = (enum CborParserGlobalFlags)flags; |
| it->parser = parser; |
| it->source.ptr = buffer; |
| it->remaining = 1; /* there's one type altogether, usually an array or map */ |
| it->flags = 0; |
| return preparse_value(it); |
| } |
| |
| CborError cbor_parser_init_reader(const struct CborParserOperations *ops, CborParser *parser, CborValue *it, void *token) |
| { |
| memset(parser, 0, sizeof(*parser)); |
| parser->source.ops = ops; |
| parser->flags = CborParserFlag_ExternalSource; |
| it->parser = parser; |
| it->source.token = token; |
| it->remaining = 1; |
| return preparse_value(it); |
| } |
| |
| /** |
| * \fn bool cbor_value_at_end(const CborValue *it) |
| * |
| * Returns true if \a it has reached the end of the iteration, usually when |
| * advancing after the last item in an array or map. |
| * |
| * In the case of the outermost CborValue object, this function returns true |
| * after decoding a single element. A pointer to the first byte of the |
| * remaining data (if any) can be obtained with cbor_value_get_next_byte(). |
| * |
| * \sa cbor_value_advance(), cbor_value_is_valid(), cbor_value_get_next_byte() |
| */ |
| |
| /** |
| * \fn const uint8_t *cbor_value_get_next_byte(const CborValue *it) |
| * |
| * Returns a pointer to the next byte that would be decoded if this CborValue |
| * object were advanced. |
| * |
| * This function is useful if cbor_value_at_end() returns true for the |
| * outermost CborValue: the pointer returned is the first byte of the data |
| * remaining in the buffer, if any. Code can decide whether to begin decoding a |
| * new CBOR data stream from this point, or parse some other data appended to |
| * the same buffer. |
| * |
| * This function may be used even after a parsing error. If that occurred, |
| * then this function returns a pointer to where the parsing error occurred. |
| * Note that the error recovery is not precise and the pointer may not indicate |
| * the exact byte containing bad data. |
| * |
| * This function makes sense only when using a linear buffer (that is, when the |
| * parser is initialize by cbor_parser_init()). If using an external source, |
| * this function may return garbage; instead, consult the external source itself |
| * to find out more details about the presence of more data. |
| * |
| * \sa cbor_value_at_end() |
| */ |
| |
| CborError cbor_value_reparse(CborValue *it) |
| { |
| if (it->flags & CborIteratorFlag_IteratingStringChunks) |
| return CborNoError; |
| return preparse_next_value_nodecrement(it); |
| } |
| |
| /** |
| * \fn bool cbor_value_is_valid(const CborValue *it) |
| * |
| * Returns true if the iterator \a it contains a valid value. Invalid iterators |
| * happen when iteration reaches the end of a container (see \ref |
| * cbor_value_at_end()) or when a search function resulted in no matches. |
| * |
| * \sa cbor_value_advance(), cbor_value_at_end(), cbor_value_get_type() |
| */ |
| |
| /** |
| * Performs a basic validation of the CBOR stream pointed by \a it and returns |
| * the error it found. If no error was found, it returns CborNoError and the |
| * application can iterate over the items with certainty that no other errors |
| * will appear during parsing. |
| * |
| * A basic validation checks for: |
| * \list |
| * \li absence of undefined additional information bytes; |
| * \li well-formedness of all numbers, lengths, and simple values; |
| * \li string contents match reported sizes; |
| * \li arrays and maps contain the number of elements they are reported to have; |
| * \endlist |
| * |
| * For further checks, see cbor_value_validate(). |
| * |
| * This function has the same timing and memory requirements as |
| * cbor_value_advance(). |
| * |
| * \sa cbor_value_validate(), cbor_value_advance() |
| */ |
| CborError cbor_value_validate_basic(const CborValue *it) |
| { |
| CborValue value = *it; |
| return cbor_value_advance(&value); |
| } |
| |
| /** |
| * Advances the CBOR value \a it by one fixed-size position. Fixed-size types |
| * are: integers, tags, simple types (including boolean, null and undefined |
| * values) and floating point types. |
| * |
| * If the type is not of fixed size, this function has undefined behavior. Code |
| * must be sure that the current type is one of the fixed-size types before |
| * calling this function. This function is provided because it can guarantee |
| * that it runs in constant time (O(1)). |
| * |
| * If the caller is not able to determine whether the type is fixed or not, code |
| * can use the cbor_value_advance() function instead. |
| * |
| * \sa cbor_value_at_end(), cbor_value_advance(), cbor_value_enter_container(), cbor_value_leave_container() |
| */ |
| CborError cbor_value_advance_fixed(CborValue *it) |
| { |
| cbor_assert(it->type != CborInvalidType); |
| cbor_assert(is_fixed_type(it->type)); |
| if (!it->remaining) |
| return CborErrorAdvancePastEOF; |
| return advance_internal(it); |
| } |
| |
| static CborError advance_recursive(CborValue *it, int nestingLevel) |
| { |
| CborError err; |
| CborValue recursed; |
| |
| if (is_fixed_type(it->type)) |
| return advance_internal(it); |
| |
| if (!cbor_value_is_container(it)) { |
| size_t len = SIZE_MAX; |
| return _cbor_value_copy_string(it, NULL, &len, it); |
| } |
| |
| /* map or array */ |
| if (nestingLevel == 0) |
| return CborErrorNestingTooDeep; |
| |
| err = cbor_value_enter_container(it, &recursed); |
| if (err) |
| return err; |
| while (!cbor_value_at_end(&recursed)) { |
| err = advance_recursive(&recursed, nestingLevel - 1); |
| if (err) |
| return err; |
| } |
| return cbor_value_leave_container(it, &recursed); |
| } |
| |
| |
| /** |
| * Advances the CBOR value \a it by one element, skipping over containers. |
| * Unlike cbor_value_advance_fixed(), this function can be called on a CBOR |
| * value of any type. However, if the type is a container (map or array) or a |
| * string with a chunked payload, this function will not run in constant time |
| * and will recurse into itself (it will run on O(n) time for the number of |
| * elements or chunks and will use O(n) memory for the number of nested |
| * containers). |
| * |
| * The number of recursions can be limited at compile time to avoid stack |
| * exhaustion in constrained systems. |
| * |
| * \sa cbor_value_at_end(), cbor_value_advance_fixed(), cbor_value_enter_container(), cbor_value_leave_container() |
| */ |
| CborError cbor_value_advance(CborValue *it) |
| { |
| cbor_assert(it->type != CborInvalidType); |
| if (!it->remaining) |
| return CborErrorAdvancePastEOF; |
| return advance_recursive(it, CBOR_PARSER_MAX_RECURSIONS); |
| } |
| |
| /** |
| * \fn bool cbor_value_is_tag(const CborValue *value) |
| * |
| * Returns true if the iterator \a value is valid and points to a CBOR tag. |
| * |
| * \sa cbor_value_get_tag(), cbor_value_skip_tag() |
| */ |
| |
| /** |
| * \fn CborError cbor_value_get_tag(const CborValue *value, CborTag *result) |
| * |
| * Retrieves the CBOR tag value that \a value points to and stores it in \a |
| * result. If the iterator \a value does not point to a CBOR tag value, the |
| * behavior is undefined, so checking with \ref cbor_value_get_type or with |
| * \ref cbor_value_is_tag is recommended. |
| * |
| * \sa cbor_value_get_type(), cbor_value_is_valid(), cbor_value_is_tag() |
| */ |
| |
| /** |
| * Advances the CBOR value \a it until it no longer points to a tag. If \a it is |
| * already not pointing to a tag, then this function returns it unchanged. |
| * |
| * This function does not run in constant time: it will run on O(n) for n being |
| * the number of tags. It does use constant memory (O(1) memory requirements). |
| * |
| * \sa cbor_value_advance_fixed(), cbor_value_advance() |
| */ |
| CborError cbor_value_skip_tag(CborValue *it) |
| { |
| while (cbor_value_is_tag(it)) { |
| CborError err = cbor_value_advance_fixed(it); |
| if (err) |
| return err; |
| } |
| return CborNoError; |
| } |
| |
| /** |
| * \fn bool cbor_value_is_container(const CborValue *it) |
| * |
| * Returns true if the \a it value is a container and requires recursion in |
| * order to decode (maps and arrays), false otherwise. |
| */ |
| |
| /** |
| * Creates a CborValue iterator pointing to the first element of the container |
| * represented by \a it and saves it in \a recursed. The \a it container object |
| * needs to be kept and passed again to cbor_value_leave_container() in order |
| * to continue iterating past this container. |
| * |
| * The \a it CborValue iterator must point to a container. |
| * |
| * \sa cbor_value_is_container(), cbor_value_leave_container(), cbor_value_advance() |
| */ |
| CborError cbor_value_enter_container(const CborValue *it, CborValue *recursed) |
| { |
| cbor_static_assert(CborIteratorFlag_ContainerIsMap == (CborMapType & ~CborArrayType)); |
| cbor_assert(cbor_value_is_container(it)); |
| *recursed = *it; |
| |
| if (it->flags & CborIteratorFlag_UnknownLength) { |
| recursed->remaining = UINT32_MAX; |
| advance_bytes(recursed, 1); |
| } else { |
| uint64_t len = extract_number_and_advance(recursed); |
| |
| recursed->remaining = (uint32_t)len; |
| if (recursed->remaining != len || len == UINT32_MAX) { |
| /* back track the pointer to indicate where the error occurred */ |
| copy_current_position(recursed, it); |
| return CborErrorDataTooLarge; |
| } |
| if (recursed->type == CborMapType) { |
| /* maps have keys and values, so we need to multiply by 2 */ |
| if (recursed->remaining > UINT32_MAX / 2) { |
| /* back track the pointer to indicate where the error occurred */ |
| copy_current_position(recursed, it); |
| return CborErrorDataTooLarge; |
| } |
| recursed->remaining *= 2; |
| } |
| if (len == 0) { |
| /* the case of the empty container */ |
| recursed->type = CborInvalidType; |
| return CborNoError; |
| } |
| } |
| recursed->flags = (recursed->type & CborIteratorFlag_ContainerIsMap); |
| return preparse_next_value_nodecrement(recursed); |
| } |
| |
| /** |
| * Updates \a it to point to the next element after the container. The \a |
| * recursed object needs to point to the element obtained either by advancing |
| * the last element of the container (via cbor_value_advance(), |
| * cbor_value_advance_fixed(), a nested cbor_value_leave_container(), or the \c |
| * next pointer from cbor_value_copy_string() or cbor_value_dup_string()). |
| * |
| * The \a it and \a recursed parameters must be the exact same as passed to |
| * cbor_value_enter_container(). |
| * |
| * \sa cbor_value_enter_container(), cbor_value_at_end() |
| */ |
| CborError cbor_value_leave_container(CborValue *it, const CborValue *recursed) |
| { |
| cbor_assert(cbor_value_is_container(it)); |
| cbor_assert(recursed->type == CborInvalidType); |
| |
| copy_current_position(it, recursed); |
| if (recursed->flags & CborIteratorFlag_UnknownLength) |
| advance_bytes(it, 1); |
| return preparse_next_value(it); |
| } |
| |
| |
| /** |
| * \fn CborType cbor_value_get_type(const CborValue *value) |
| * |
| * Returns the type of the CBOR value that the iterator \a value points to. If |
| * \a value does not point to a valid value, this function returns \ref |
| * CborInvalidType. |
| * |
| * TinyCBOR also provides functions to test directly if a given CborValue object |
| * is of a given type, like cbor_value_is_text_string() and cbor_value_is_null(). |
| * |
| * \sa cbor_value_is_valid() |
| */ |
| |
| /** |
| * \fn bool cbor_value_is_null(const CborValue *value) |
| * |
| * Returns true if the iterator \a value is valid and points to a CBOR null type. |
| * |
| * \sa cbor_value_is_valid(), cbor_value_is_undefined() |
| */ |
| |
| /** |
| * \fn bool cbor_value_is_undefined(const CborValue *value) |
| * |
| * Returns true if the iterator \a value is valid and points to a CBOR undefined type. |
| * |
| * \sa cbor_value_is_valid(), cbor_value_is_null() |
| */ |
| |
| /** |
| * \fn bool cbor_value_is_boolean(const CborValue *value) |
| * |
| * Returns true if the iterator \a value is valid and points to a CBOR boolean |
| * type (true or false). |
| * |
| * \sa cbor_value_is_valid(), cbor_value_get_boolean() |
| */ |
| |
| /** |
| * \fn CborError cbor_value_get_boolean(const CborValue *value, bool *result) |
| * |
| * Retrieves the boolean value that \a value points to and stores it in \a |
| * result. If the iterator \a value does not point to a boolean value, the |
| * behavior is undefined, so checking with \ref cbor_value_get_type or with |
| * \ref cbor_value_is_boolean is recommended. |
| * |
| * \sa cbor_value_get_type(), cbor_value_is_valid(), cbor_value_is_boolean() |
| */ |
| |
| /** |
| * \fn bool cbor_value_is_simple_type(const CborValue *value) |
| * |
| * Returns true if the iterator \a value is valid and points to a CBOR Simple Type |
| * type (other than true, false, null and undefined). |
| * |
| * \sa cbor_value_is_valid(), cbor_value_get_simple_type() |
| */ |
| |
| /** |
| * \fn CborError cbor_value_get_simple_type(const CborValue *value, uint8_t *result) |
| * |
| * Retrieves the CBOR Simple Type value that \a value points to and stores it |
| * in \a result. If the iterator \a value does not point to a simple_type |
| * value, the behavior is undefined, so checking with \ref cbor_value_get_type |
| * or with \ref cbor_value_is_simple_type is recommended. |
| * |
| * \sa cbor_value_get_type(), cbor_value_is_valid(), cbor_value_is_simple_type() |
| */ |
| |
| /** |
| * \fn bool cbor_value_is_integer(const CborValue *value) |
| * |
| * Returns true if the iterator \a value is valid and points to a CBOR integer |
| * type. |
| * |
| * \sa cbor_value_is_valid(), cbor_value_get_int, cbor_value_get_int64, cbor_value_get_uint64, cbor_value_get_raw_integer |
| */ |
| |
| /** |
| * \fn bool cbor_value_is_unsigned_integer(const CborValue *value) |
| * |
| * Returns true if the iterator \a value is valid and points to a CBOR unsigned |
| * integer type (positive values or zero). |
| * |
| * \sa cbor_value_is_valid(), cbor_value_get_uint64() |
| */ |
| |
| /** |
| * \fn bool cbor_value_is_negative_integer(const CborValue *value) |
| * |
| * Returns true if the iterator \a value is valid and points to a CBOR negative |
| * integer type. |
| * |
| * \sa cbor_value_is_valid(), cbor_value_get_int, cbor_value_get_int64, cbor_value_get_raw_integer |
| */ |
| |
| /** |
| * \fn CborError cbor_value_get_int(const CborValue *value, int *result) |
| * |
| * Retrieves the CBOR integer value that \a value points to and stores it in \a |
| * result. If the iterator \a value does not point to an integer value, the |
| * behavior is undefined, so checking with \ref cbor_value_get_type or with |
| * \ref cbor_value_is_integer is recommended. |
| * |
| * Note that this function does not do range-checking: integral values that do |
| * not fit in a variable of type \c{int} are silently truncated to fit. Use |
| * cbor_value_get_int_checked() if that is not acceptable. |
| * |
| * \sa cbor_value_get_type(), cbor_value_is_valid(), cbor_value_is_integer() |
| */ |
| |
| /** |
| * \fn CborError cbor_value_get_int64(const CborValue *value, int64_t *result) |
| * |
| * Retrieves the CBOR integer value that \a value points to and stores it in \a |
| * result. If the iterator \a value does not point to an integer value, the |
| * behavior is undefined, so checking with \ref cbor_value_get_type or with |
| * \ref cbor_value_is_integer is recommended. |
| * |
| * Note that this function does not do range-checking: integral values that do |
| * not fit in a variable of type \c{int64_t} are silently truncated to fit. Use |
| * cbor_value_get_int64_checked() that is not acceptable. |
| * |
| * \sa cbor_value_get_type(), cbor_value_is_valid(), cbor_value_is_integer() |
| */ |
| |
| /** |
| * \fn CborError cbor_value_get_uint64(const CborValue *value, uint64_t *result) |
| * |
| * Retrieves the CBOR integer value that \a value points to and stores it in \a |
| * result. If the iterator \a value does not point to an unsigned integer |
| * value, the behavior is undefined, so checking with \ref cbor_value_get_type |
| * or with \ref cbor_value_is_unsigned_integer is recommended. |
| * |
| * \sa cbor_value_get_type(), cbor_value_is_valid(), cbor_value_is_unsigned_integer() |
| */ |
| |
| /** |
| * \fn CborError cbor_value_get_raw_integer(const CborValue *value, uint64_t *result) |
| * |
| * Retrieves the CBOR integer value that \a value points to and stores it in \a |
| * result. If the iterator \a value does not point to an integer value, the |
| * behavior is undefined, so checking with \ref cbor_value_get_type or with |
| * \ref cbor_value_is_integer is recommended. |
| * |
| * This function is provided because CBOR negative integers can assume values |
| * that cannot be represented with normal 64-bit integer variables. |
| * |
| * If the integer is unsigned (that is, if cbor_value_is_unsigned_integer() |
| * returns true), then \a result will contain the actual value. If the integer |
| * is negative, then \a result will contain the absolute value of that integer, |
| * minus one. That is, \c {actual = -result - 1}. On architectures using two's |
| * complement for representation of negative integers, it is equivalent to say |
| * that \a result will contain the bitwise negation of the actual value. |
| * |
| * \sa cbor_value_get_type(), cbor_value_is_valid(), cbor_value_is_integer() |
| */ |
| |
| /** |
| * Retrieves the CBOR integer value that \a value points to and stores it in \a |
| * result. If the iterator \a value does not point to an integer value, the |
| * behavior is undefined, so checking with \ref cbor_value_get_type or with |
| * \ref cbor_value_is_integer is recommended. |
| * |
| * Unlike \ref cbor_value_get_int64(), this function performs a check to see if the |
| * stored integer fits in \a result without data loss. If the number is outside |
| * the valid range for the data type, this function returns the recoverable |
| * error CborErrorDataTooLarge. In that case, use either |
| * cbor_value_get_uint64() (if the number is positive) or |
| * cbor_value_get_raw_integer(). |
| * |
| * \sa cbor_value_get_type(), cbor_value_is_valid(), cbor_value_is_integer(), cbor_value_get_int64() |
| */ |
| CborError cbor_value_get_int64_checked(const CborValue *value, int64_t *result) |
| { |
| uint64_t v; |
| cbor_assert(cbor_value_is_integer(value)); |
| v = _cbor_value_extract_int64_helper(value); |
| |
| /* Check before converting, as the standard says (C11 6.3.1.3 paragraph 3): |
| * "[if] the new type is signed and the value cannot be represented in it; either the |
| * result is implementation-defined or an implementation-defined signal is raised." |
| * |
| * The range for int64_t is -2^63 to 2^63-1 (int64_t is required to be |
| * two's complement, C11 7.20.1.1 paragraph 3), which in CBOR is |
| * represented the same way, differing only on the "sign bit" (the major |
| * type). |
| */ |
| |
| if (unlikely(v > (uint64_t)INT64_MAX)) |
| return CborErrorDataTooLarge; |
| |
| *result = v; |
| if (value->flags & CborIteratorFlag_NegativeInteger) |
| *result = -*result - 1; |
| return CborNoError; |
| } |
| |
| /** |
| * Retrieves the CBOR integer value that \a value points to and stores it in \a |
| * result. If the iterator \a value does not point to an integer value, the |
| * behavior is undefined, so checking with \ref cbor_value_get_type or with |
| * \ref cbor_value_is_integer is recommended. |
| * |
| * Unlike \ref cbor_value_get_int(), this function performs a check to see if the |
| * stored integer fits in \a result without data loss. If the number is outside |
| * the valid range for the data type, this function returns the recoverable |
| * error CborErrorDataTooLarge. In that case, use one of the other integer |
| * functions to obtain the value. |
| * |
| * \sa cbor_value_get_type(), cbor_value_is_valid(), cbor_value_is_integer(), cbor_value_get_int64(), |
| * cbor_value_get_uint64(), cbor_value_get_int64_checked(), cbor_value_get_raw_integer() |
| */ |
| CborError cbor_value_get_int_checked(const CborValue *value, int *result) |
| { |
| uint64_t v; |
| cbor_assert(cbor_value_is_integer(value)); |
| v = _cbor_value_extract_int64_helper(value); |
| |
| /* Check before converting, as the standard says (C11 6.3.1.3 paragraph 3): |
| * "[if] the new type is signed and the value cannot be represented in it; either the |
| * result is implementation-defined or an implementation-defined signal is raised." |
| * |
| * But we can convert from signed to unsigned without fault (paragraph 2). |
| * |
| * The range for int is implementation-defined and int is not guaranteed to use |
| * two's complement representation (although int32_t is). |
| */ |
| |
| if (value->flags & CborIteratorFlag_NegativeInteger) { |
| if (unlikely(v > (unsigned) -(INT_MIN + 1))) |
| return CborErrorDataTooLarge; |
| |
| *result = (int)v; |
| *result = -*result - 1; |
| } else { |
| if (unlikely(v > (uint64_t)INT_MAX)) |
| return CborErrorDataTooLarge; |
| |
| *result = (int)v; |
| } |
| return CborNoError; |
| |
| } |
| |
| /** |
| * \fn bool cbor_value_is_length_known(const CborValue *value) |
| * |
| * Returns true if the length of this type is known without calculation. That |
| * is, if the length of this CBOR string, map or array is encoded in the data |
| * stream, this function returns true. If the length is not encoded, it returns |
| * false. |
| * |
| * If the length is known, code can call cbor_value_get_string_length(), |
| * cbor_value_get_array_length() or cbor_value_get_map_length() to obtain the |
| * length. If the length is not known but is necessary, code can use the |
| * cbor_value_calculate_string_length() function (no equivalent function is |
| * provided for maps and arrays). |
| */ |
| |
| /** |
| * \fn bool cbor_value_is_text_string(const CborValue *value) |
| * |
| * Returns true if the iterator \a value is valid and points to a CBOR text |
| * string. CBOR text strings are UTF-8 encoded and usually contain |
| * human-readable text. |
| * |
| * \sa cbor_value_is_valid(), cbor_value_get_string_length(), cbor_value_calculate_string_length(), |
| * cbor_value_copy_text_string(), cbor_value_dup_text_string() |
| */ |
| |
| /** |
| * \fn bool cbor_value_is_byte_string(const CborValue *value) |
| * |
| * Returns true if the iterator \a value is valid and points to a CBOR byte |
| * string. CBOR byte strings are binary data with no specified encoding or |
| * format. |
| * |
| * \sa cbor_value_is_valid(), cbor_value_get_string_length(), cbor_value_calculate_string_length(), |
| * cbor_value_copy_byte_string(), cbor_value_dup_byte_string() |
| */ |
| |
| /** |
| * \fn CborError cbor_value_get_string_length(const CborValue *value, size_t *length) |
| * |
| * Extracts the length of the byte or text string that \a value points to and |
| * stores it in \a result. If the iterator \a value does not point to a text |
| * string or a byte string, the behaviour is undefined, so checking with \ref |
| * cbor_value_get_type, with \ref cbor_value_is_text_string or \ref |
| * cbor_value_is_byte_string is recommended. |
| * |
| * If the length of this string is not encoded in the CBOR data stream, this |
| * function will return the recoverable error CborErrorUnknownLength. You may |
| * also check whether that is the case by using cbor_value_is_length_known(). |
| * |
| * If the length of the string is required but the length was not encoded, use |
| * cbor_value_calculate_string_length(), but note that that function does not |
| * run in constant time. |
| * |
| * \note On 32-bit platforms, this function will return error condition of \ref |
| * CborErrorDataTooLarge if the stream indicates a length that is too big to |
| * fit in 32-bit. |
| * |
| * \sa cbor_value_is_valid(), cbor_value_is_length_known(), cbor_value_calculate_string_length() |
| */ |
| |
| /** |
| * Calculates the length of the byte or text string that \a value points to and |
| * stores it in \a len. If the iterator \a value does not point to a text |
| * string or a byte string, the behaviour is undefined, so checking with \ref |
| * cbor_value_get_type, with \ref cbor_value_is_text_string or \ref |
| * cbor_value_is_byte_string is recommended. |
| * |
| * This function is different from cbor_value_get_string_length() in that it |
| * calculates the length even for strings sent in chunks. For that reason, this |
| * function may not run in constant time (it will run in O(n) time on the |
| * number of chunks). It does use constant memory (O(1)). |
| * |
| * \note On 32-bit platforms, this function will return error condition of \ref |
| * CborErrorDataTooLarge if the stream indicates a length that is too big to |
| * fit in 32-bit. |
| * |
| * \sa cbor_value_get_string_length(), cbor_value_copy_text_string(), cbor_value_copy_byte_string(), cbor_value_is_length_known() |
| */ |
| CborError cbor_value_calculate_string_length(const CborValue *value, size_t *len) |
| { |
| *len = SIZE_MAX; |
| return _cbor_value_copy_string(value, NULL, len, NULL); |
| } |
| |
| CborError _cbor_value_begin_string_iteration(CborValue *it) |
| { |
| it->flags |= CborIteratorFlag_IteratingStringChunks | |
| CborIteratorFlag_BeforeFirstStringChunk; |
| if (!cbor_value_is_length_known(it)) { |
| /* chunked string: we're before the first chunk; |
| * advance to the first chunk */ |
| advance_bytes(it, 1); |
| } |
| |
| return CborNoError; |
| } |
| |
| CborError _cbor_value_finish_string_iteration(CborValue *it) |
| { |
| if (!cbor_value_is_length_known(it)) |
| advance_bytes(it, 1); /* skip the Break */ |
| |
| return preparse_next_value(it); |
| } |
| |
| static CborError get_string_chunk_size(const CborValue *it, size_t *offset, size_t *len) |
| { |
| uint8_t descriptor; |
| size_t bytesNeeded = 1; |
| |
| if (cbor_value_is_length_known(it) && (it->flags & CborIteratorFlag_BeforeFirstStringChunk) == 0) |
| return CborErrorNoMoreStringChunks; |
| |
| /* are we at the end? */ |
| if (!read_bytes(it, &descriptor, 0, 1)) |
| return CborErrorUnexpectedEOF; |
| |
| if (descriptor == BreakByte) |
| return CborErrorNoMoreStringChunks; |
| if ((descriptor & MajorTypeMask) != it->type) |
| return CborErrorIllegalType; |
| |
| /* find the string length */ |
| descriptor &= SmallValueMask; |
| if (descriptor < Value8Bit) { |
| *len = descriptor; |
| } else if (unlikely(descriptor > Value64Bit)) { |
| return CborErrorIllegalNumber; |
| } else { |
| uint64_t val; |
| bytesNeeded = (size_t)(1 << (descriptor - Value8Bit)); |
| if (!can_read_bytes(it, 1 + bytesNeeded)) |
| return CborErrorUnexpectedEOF; |
| |
| if (descriptor <= Value16Bit) { |
| if (descriptor == Value16Bit) |
| val = read_uint16(it, 1); |
| else |
| val = read_uint8(it, 1); |
| } else { |
| if (descriptor == Value32Bit) |
| val = read_uint32(it, 1); |
| else |
| val = read_uint64(it, 1); |
| } |
| |
| *len = val; |
| if (*len != val) |
| return CborErrorDataTooLarge; |
| |
| ++bytesNeeded; |
| } |
| |
| *offset = bytesNeeded; |
| return CborNoError; |
| } |
| |
| CborError _cbor_value_get_string_chunk_size(const CborValue *value, size_t *len) |
| { |
| size_t offset; |
| return get_string_chunk_size(value, &offset, len); |
| } |
| |
| static CborError get_string_chunk(CborValue *it, const void **bufferptr, size_t *len) |
| { |
| size_t offset; |
| CborError err = get_string_chunk_size(it, &offset, len); |
| if (err) |
| return err; |
| |
| /* we're good, transfer the string now */ |
| err = transfer_string(it, bufferptr, offset, *len); |
| if (err) |
| return err; |
| |
| /* we've iterated at least once */ |
| it->flags &= ~CborIteratorFlag_BeforeFirstStringChunk; |
| return CborNoError; |
| } |
| |
| /** |
| * \fn CborError cbor_value_get_text_string_chunk(const CborValue *value, const char **bufferptr, size_t *len, CborValue *next) |
| * |
| * Extracts one text string chunk pointed to by \a value and stores a pointer |
| * to the data in \a buffer and the size in \a len, which must not be null. If |
| * no more chunks are available, then \a bufferptr will be set to null. This |
| * function may be used to iterate over any string without causing its contents |
| * to be copied to a separate buffer, like the convenience function |
| * cbor_value_copy_text_string() does. |
| * |
| * It is designed to be used in code like: |
| * |
| * \code |
| * if (cbor_value_is_text_string(value)) { |
| * char *ptr; |
| * size_t len; |
| * while (1) { |
| * err = cbor_value_get_text_string_chunk(value, &ptr, &len, &value)); |
| * if (err) return err; |
| * if (ptr == NULL) return CborNoError; |
| * consume(ptr, len); |
| * } |
| * } |
| * \endcode |
| * |
| * If the iterator \a value does not point to a text string, the behaviour is |
| * undefined, so checking with \ref cbor_value_get_type or \ref |
| * cbor_value_is_text_string is recommended. |
| * |
| * The \a next pointer, if not null, will be updated to point to the next item |
| * after this string. During iteration, the pointer must only be passed back |
| * again to this function; passing it to any other function in this library |
| * results in undefined behavior. If there are no more chunks to be read from |
| * \a value, then \a next will be set to the next item after this string; if \a |
| * value points to the last item, then \a next will be invalid. |
| * |
| * \note This function does not perform UTF-8 validation on the incoming text |
| * string. |
| * |
| * \sa cbor_value_dup_text_string(), cbor_value_copy_text_string(), cbor_value_caculate_string_length(), cbor_value_get_byte_string_chunk() |
| */ |
| |
| /** |
| * \fn CborError cbor_value_get_byte_string_chunk(const CborValue *value, const char **bufferptr, size_t *len, CborValue *next) |
| * |
| * Extracts one byte string chunk pointed to by \a value and stores a pointer |
| * to the data in \a buffer and the size in \a len, which must not be null. If |
| * no more chunks are available, then \a bufferptr will be set to null. This |
| * function may be used to iterate over any string without causing its contents |
| * to be copied to a separate buffer, like the convenience function |
| * cbor_value_copy_byte_string() does. |
| * |
| * It is designed to be used in code like: |
| * |
| * \code |
| * if (cbor_value_is_byte_string(value)) { |
| * char *ptr; |
| * size_t len; |
| * while (1) { |
| * err = cbor_value_get_byte_string_chunk(value, &ptr, &len, &value)); |
| * if (err) return err; |
| * if (ptr == NULL) return CborNoError; |
| * consume(ptr, len); |
| * } |
| * } |
| * \endcode |
| * |
| * If the iterator \a value does not point to a byte string, the behaviour is |
| * undefined, so checking with \ref cbor_value_get_type or \ref |
| * cbor_value_is_byte_string is recommended. |
| * |
| * The \a next pointer, if not null, will be updated to point to the next item |
| * after this string. During iteration, the pointer must only be passed back |
| * again to this function; passing it to any other function in this library |
| * results in undefined behavior. If there are no more chunks to be read from |
| * \a value, then \a next will be set to the next item after this string; if \a |
| * value points to the last item, then \a next will be invalid. |
| * |
| * \sa cbor_value_dup_byte_string(), cbor_value_copy_byte_string(), cbor_value_caculate_string_length(), cbor_value_get_text_string_chunk() |
| */ |
| |
| CborError _cbor_value_get_string_chunk(const CborValue *value, const void **bufferptr, |
| size_t *len, CborValue *next) |
| { |
| CborValue tmp; |
| if (!next) |
| next = &tmp; |
| *next = *value; |
| return get_string_chunk(next, bufferptr, len); |
| } |
| |
| /* We return uintptr_t so that we can pass memcpy directly as the iteration |
| * function. The choice is to optimize for memcpy, which is used in the base |
| * parser API (cbor_value_copy_string), while memcmp is used in convenience API |
| * only. */ |
| typedef uintptr_t (*IterateFunction)(char *, const uint8_t *, size_t); |
| |
| static uintptr_t iterate_noop(char *dest, const uint8_t *src, size_t len) |
| { |
| (void)dest; |
| (void)src; |
| (void)len; |
| return true; |
| } |
| |
| static uintptr_t iterate_memcmp(char *s1, const uint8_t *s2, size_t len) |
| { |
| return memcmp(s1, (const char *)s2, len) == 0; |
| } |
| |
| static uintptr_t iterate_memcpy(char *dest, const uint8_t *src, size_t len) |
| { |
| return (uintptr_t)memcpy(dest, src, len); |
| } |
| |
| static CborError iterate_string_chunks(const CborValue *value, char *buffer, size_t *buflen, |
| bool *result, CborValue *next, IterateFunction func) |
| { |
| CborError err; |
| CborValue tmp; |
| size_t total = 0; |
| const void *ptr; |
| |
| cbor_assert(cbor_value_is_byte_string(value) || cbor_value_is_text_string(value)); |
| if (!next) |
| next = &tmp; |
| *next = *value; |
| *result = true; |
| |
| err = _cbor_value_begin_string_iteration(next); |
| if (err) |
| return err; |
| |
| while (1) { |
| size_t newTotal; |
| size_t chunkLen; |
| err = get_string_chunk(next, &ptr, &chunkLen); |
| if (err == CborErrorNoMoreStringChunks) |
| break; |
| if (err) |
| return err; |
| |
| if (unlikely(add_check_overflow(total, chunkLen, &newTotal))) |
| return CborErrorDataTooLarge; |
| |
| if (*result && *buflen >= newTotal) |
| *result = !!func(buffer + total, (const uint8_t *)ptr, chunkLen); |
| else |
| *result = false; |
| |
| total = newTotal; |
| } |
| |
| /* is there enough room for the ending NUL byte? */ |
| if (*result && *buflen > total) { |
| uint8_t nul[] = { 0 }; |
| *result = !!func(buffer + total, nul, 1); |
| } |
| *buflen = total; |
| return _cbor_value_finish_string_iteration(next); |
| } |
| |
| /** |
| * \fn CborError cbor_value_copy_text_string(const CborValue *value, char *buffer, size_t *buflen, CborValue *next) |
| * |
| * Copies the string pointed to by \a value into the buffer provided at \a buffer |
| * of \a buflen bytes. If \a buffer is a NULL pointer, this function will not |
| * copy anything and will only update the \a next value. |
| * |
| * If the iterator \a value does not point to a text string, the behaviour is |
| * undefined, so checking with \ref cbor_value_get_type or \ref |
| * cbor_value_is_text_string is recommended. |
| * |
| * If the provided buffer length was too small, this function returns an error |
| * condition of \ref CborErrorOutOfMemory. If you need to calculate the length |
| * of the string in order to preallocate a buffer, use |
| * cbor_value_calculate_string_length(). |
| * |
| * On success, this function sets the number of bytes copied to \c{*buflen}. If |
| * the buffer is large enough, this function will insert a null byte after the |
| * last copied byte, to facilitate manipulation of text strings. That byte is |
| * not included in the returned value of \c{*buflen}. If there was no space for |
| * the terminating null, no error is returned, so callers must check the value |
| * of *buflen after the call, before relying on the '\0'; if it has not been |
| * changed by the call, there is no '\0'-termination on the buffer's contents. |
| * |
| * The \a next pointer, if not null, will be updated to point to the next item |
| * after this string. If \a value points to the last item, then \a next will be |
| * invalid. |
| * |
| * This function may not run in constant time (it will run in O(n) time on the |
| * number of chunks). It requires constant memory (O(1)). |
| * |
| * \note This function does not perform UTF-8 validation on the incoming text |
| * string. |
| * |
| * \sa cbor_value_get_text_string_chunk() cbor_value_dup_text_string(), cbor_value_copy_byte_string(), cbor_value_get_string_length(), cbor_value_calculate_string_length() |
| */ |
| |
| /** |
| * \fn CborError cbor_value_copy_byte_string(const CborValue *value, uint8_t *buffer, size_t *buflen, CborValue *next) |
| * |
| * Copies the string pointed by \a value into the buffer provided at \a buffer |
| * of \a buflen bytes. If \a buffer is a NULL pointer, this function will not |
| * copy anything and will only update the \a next value. |
| * |
| * If the iterator \a value does not point to a byte string, the behaviour is |
| * undefined, so checking with \ref cbor_value_get_type or \ref |
| * cbor_value_is_byte_string is recommended. |
| * |
| * If the provided buffer length was too small, this function returns an error |
| * condition of \ref CborErrorOutOfMemory. If you need to calculate the length |
| * of the string in order to preallocate a buffer, use |
| * cbor_value_calculate_string_length(). |
| * |
| * On success, this function sets the number of bytes copied to \c{*buflen}. If |
| * the buffer is large enough, this function will insert a null byte after the |
| * last copied byte, to facilitate manipulation of null-terminated strings. |
| * That byte is not included in the returned value of \c{*buflen}. |
| * |
| * The \a next pointer, if not null, will be updated to point to the next item |
| * after this string. If \a value points to the last item, then \a next will be |
| * invalid. |
| * |
| * This function may not run in constant time (it will run in O(n) time on the |
| * number of chunks). It requires constant memory (O(1)). |
| * |
| * \sa cbor_value_get_byte_string_chunk(), cbor_value_dup_text_string(), cbor_value_copy_text_string(), cbor_value_get_string_length(), cbor_value_calculate_string_length() |
| */ |
| |
| CborError _cbor_value_copy_string(const CborValue *value, void *buffer, |
| size_t *buflen, CborValue *next) |
| { |
| bool copied_all; |
| CborError err = iterate_string_chunks(value, (char*)buffer, buflen, &copied_all, next, |
| buffer ? iterate_memcpy : iterate_noop); |
| return err ? err : |
| copied_all ? CborNoError : CborErrorOutOfMemory; |
| } |
| |
| /** |
| * Compares the entry \a value with the string \a string and stores the result |
| * in \a result. If the value is different from \a string \a result will |
| * contain \c false. |
| * |
| * The entry at \a value may be a tagged string. If \a value is not a string or |
| * a tagged string, the comparison result will be false. |
| * |
| * CBOR requires text strings to be encoded in UTF-8, but this function does |
| * not validate either the strings in the stream or the string \a string to be |
| * matched. Moreover, comparison is done on strict codepoint comparison, |
| * without any Unicode normalization. |
| * |
| * This function may not run in constant time (it will run in O(n) time on the |
| * number of chunks). It requires constant memory (O(1)). |
| * |
| * \sa cbor_value_skip_tag(), cbor_value_copy_text_string() |
| */ |
| CborError cbor_value_text_string_equals(const CborValue *value, const char *string, bool *result) |
| { |
| size_t len; |
| CborValue copy = *value; |
| CborError err = cbor_value_skip_tag(©); |
| if (err) |
| return err; |
| if (!cbor_value_is_text_string(©)) { |
| *result = false; |
| return CborNoError; |
| } |
| |
| len = strlen(string); |
| return iterate_string_chunks(©, CONST_CAST(char *, string), &len, result, NULL, iterate_memcmp); |
| } |
| |
| /** |
| * \fn bool cbor_value_is_array(const CborValue *value) |
| * |
| * Returns true if the iterator \a value is valid and points to a CBOR array. |
| * |
| * \sa cbor_value_is_valid(), cbor_value_is_map() |
| */ |
| |
| /** |
| * \fn CborError cbor_value_get_array_length(const CborValue *value, size_t *length) |
| * |
| * Extracts the length of the CBOR array that \a value points to and stores it |
| * in \a result. If the iterator \a value does not point to a CBOR array, the |
| * behaviour is undefined, so checking with \ref cbor_value_get_type or \ref |
| * cbor_value_is_array is recommended. |
| * |
| * If the length of this array is not encoded in the CBOR data stream, this |
| * function will return the recoverable error CborErrorUnknownLength. You may |
| * also check whether that is the case by using cbor_value_is_length_known(). |
| * |
| * \note On 32-bit platforms, this function will return error condition of \ref |
| * CborErrorDataTooLarge if the stream indicates a length that is too big to |
| * fit in 32-bit. |
| * |
| * \sa cbor_value_is_valid(), cbor_value_is_length_known() |
| */ |
| |
| /** |
| * \fn bool cbor_value_is_map(const CborValue *value) |
| * |
| * Returns true if the iterator \a value is valid and points to a CBOR map. |
| * |
| * \sa cbor_value_is_valid(), cbor_value_is_array() |
| */ |
| |
| /** |
| * \fn CborError cbor_value_get_map_length(const CborValue *value, size_t *length) |
| * |
| * Extracts the length of the CBOR map that \a value points to and stores it in |
| * \a result. If the iterator \a value does not point to a CBOR map, the |
| * behaviour is undefined, so checking with \ref cbor_value_get_type or \ref |
| * cbor_value_is_map is recommended. |
| * |
| * If the length of this map is not encoded in the CBOR data stream, this |
| * function will return the recoverable error CborErrorUnknownLength. You may |
| * also check whether that is the case by using cbor_value_is_length_known(). |
| * |
| * \note On 32-bit platforms, this function will return error condition of \ref |
| * CborErrorDataTooLarge if the stream indicates a length that is too big to |
| * fit in 32-bit. |
| * |
| * \sa cbor_value_is_valid(), cbor_value_is_length_known() |
| */ |
| |
| /** |
| * Attempts to find the value in map \a map that corresponds to the text string |
| * entry \a string. If the iterator \a value does not point to a CBOR map, the |
| * behaviour is undefined, so checking with \ref cbor_value_get_type or \ref |
| * cbor_value_is_map is recommended. |
| * |
| * If the item is found, it is stored in \a result. If no item is found |
| * matching the key, then \a result will contain an element of type \ref |
| * CborInvalidType. Matching is performed using |
| * cbor_value_text_string_equals(), so tagged strings will also match. |
| * |
| * This function has a time complexity of O(n) where n is the number of |
| * elements in the map to be searched. In addition, this function is has O(n) |
| * memory requirement based on the number of nested containers (maps or arrays) |
| * found as elements of this map. |
| * |
| * \sa cbor_value_is_valid(), cbor_value_text_string_equals(), cbor_value_advance() |
| */ |
| CborError cbor_value_map_find_value(const CborValue *map, const char *string, CborValue *element) |
| { |
| CborError err; |
| size_t len = strlen(string); |
| cbor_assert(cbor_value_is_map(map)); |
| err = cbor_value_enter_container(map, element); |
| if (err) |
| goto error; |
| |
| while (!cbor_value_at_end(element)) { |
| /* find the non-tag so we can compare */ |
| err = cbor_value_skip_tag(element); |
| if (err) |
| goto error; |
| if (cbor_value_is_text_string(element)) { |
| bool equals; |
| size_t dummyLen = len; |
| err = iterate_string_chunks(element, CONST_CAST(char *, string), &dummyLen, |
| &equals, element, iterate_memcmp); |
| if (err) |
| goto error; |
| if (equals) |
| return preparse_value(element); |
| } else { |
| /* skip this key */ |
| err = cbor_value_advance(element); |
| if (err) |
| goto error; |
| } |
| |
| /* skip this value */ |
| err = cbor_value_skip_tag(element); |
| if (err) |
| goto error; |
| err = cbor_value_advance(element); |
| if (err) |
| goto error; |
| } |
| |
| /* not found */ |
| element->type = CborInvalidType; |
| return CborNoError; |
| |
| error: |
| element->type = CborInvalidType; |
| return err; |
| } |
| |
| /** |
| * \fn bool cbor_value_is_float(const CborValue *value) |
| * |
| * Returns true if the iterator \a value is valid and points to a CBOR |
| * single-precision floating point (32-bit). |
| * |
| * \sa cbor_value_is_valid(), cbor_value_is_double(), cbor_value_is_half_float() |
| */ |
| |
| /** |
| * \fn CborError cbor_value_get_float(const CborValue *value, float *result) |
| * |
| * Retrieves the CBOR single-precision floating point (32-bit) value that \a |
| * value points to and stores it in \a result. If the iterator \a value does |
| * not point to a single-precision floating point value, the behavior is |
| * undefined, so checking with \ref cbor_value_get_type or with \ref |
| * cbor_value_is_float is recommended. |
| * |
| * \sa cbor_value_get_type(), cbor_value_is_valid(), cbor_value_is_float(), cbor_value_get_double() |
| */ |
| |
| /** |
| * \fn bool cbor_value_is_double(const CborValue *value) |
| * |
| * Returns true if the iterator \a value is valid and points to a CBOR |
| * double-precision floating point (64-bit). |
| * |
| * \sa cbor_value_is_valid(), cbor_value_is_float(), cbor_value_is_half_float() |
| */ |
| |
| /** |
| * \fn CborError cbor_value_get_double(const CborValue *value, float *result) |
| * |
| * Retrieves the CBOR double-precision floating point (64-bit) value that \a |
| * value points to and stores it in \a result. If the iterator \a value does |
| * not point to a double-precision floating point value, the behavior is |
| * undefined, so checking with \ref cbor_value_get_type or with \ref |
| * cbor_value_is_double is recommended. |
| * |
| * \sa cbor_value_get_type(), cbor_value_is_valid(), cbor_value_is_double(), cbor_value_get_float() |
| */ |
| |
| /** |
| * \fn bool cbor_value_is_half_float(const CborValue *value) |
| * |
| * Returns true if the iterator \a value is valid and points to a CBOR |
| * single-precision floating point (16-bit). |
| * |
| * \sa cbor_value_is_valid(), cbor_value_is_double(), cbor_value_is_float() |
| */ |
| |
| /** |
| * \fn CborError cbor_value_get_half_float(const CborValue *value, void *result) |
| * |
| * Retrieves the CBOR half-precision floating point (16-bit) value that \a |
| * value points to and stores it in \a result. If the iterator \a value does |
| * not point to a half-precision floating point value, the behavior is |
| * undefined, so checking with \ref cbor_value_get_type or with \ref |
| * cbor_value_is_half_float is recommended. |
| * |
| * Note: since the C language does not have a standard type for half-precision |
| * floating point, this function takes a \c{void *} as a parameter for the |
| * storage area, which must be at least 16 bits wide. |
| * |
| * \sa cbor_value_get_type(), cbor_value_is_valid(), cbor_value_is_half_float(), cbor_value_get_half_float_as_float(), cbor_value_get_float() |
| */ |
| |
| /** @} */ |