/* Copyright 2011-2017 David Robillard Permission to use, copy, modify, and/or distribute this software for any purpose with or without fee is hereby granted, provided that the above copyright notice and this permission notice appear in all copies. THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ /// @file serd.h API for Serd, a lightweight RDF syntax library #ifndef SERD_SERD_H #define SERD_SERD_H #include #include #include #include #ifdef SERD_SHARED # ifdef _WIN32 # define SERD_LIB_IMPORT __declspec(dllimport) # define SERD_LIB_EXPORT __declspec(dllexport) # else # define SERD_LIB_IMPORT __attribute__((visibility("default"))) # define SERD_LIB_EXPORT __attribute__((visibility("default"))) # endif # ifdef SERD_INTERNAL # define SERD_API SERD_LIB_EXPORT # else # define SERD_API SERD_LIB_IMPORT # endif #else # define SERD_API #endif #if defined(__GNUC__) # define SERD_LOG_FUNC(fmt, arg1) __attribute__((format(printf, fmt, arg1))) #else # define SERD_LOG_FUNC(fmt, arg1) #endif #ifdef __cplusplus extern "C" { #endif /** @defgroup serd Serd A lightweight RDF syntax library @{ */ /// Global library state typedef struct SerdWorldImpl SerdWorld; /// Hashing node container for interning and simplified memory management typedef struct SerdNodesImpl SerdNodes; /// A subject, predicate, and object, with optional graph context typedef struct SerdStatementImpl SerdStatement; /// The origin of a statement in a document typedef struct SerdCursorImpl SerdCursor; /// Lexical environment for relative URIs or CURIEs (base URI and namespaces) typedef struct SerdEnvImpl SerdEnv; /// An indexed set of statements typedef struct SerdModelImpl SerdModel; /// A statement sink that inserts into a model typedef struct SerdInserterImpl SerdInserter; /// Model Iterator typedef struct SerdIterImpl SerdIter; /// Model Range typedef struct SerdRangeImpl SerdRange; /// Streaming parser that reads a text stream and writes to a statement sink typedef struct SerdReaderImpl SerdReader; /// Streaming serialiser that writes a text stream as statements are pushed typedef struct SerdWriterImpl SerdWriter; /// An interface that receives a stream of RDF data typedef struct SerdSinkImpl SerdSink; /// A sink for bytes that receives string output typedef struct SerdByteSinkImpl SerdByteSink; /// Return status code typedef enum { SERD_SUCCESS, ///< No error SERD_FAILURE, ///< Non-fatal failure SERD_ERR_UNKNOWN, ///< Unknown error SERD_ERR_BAD_SYNTAX, ///< Invalid syntax SERD_ERR_BAD_ARG, ///< Invalid argument SERD_ERR_BAD_ITER, ///< Use of invalidated iterator SERD_ERR_NOT_FOUND, ///< Not found SERD_ERR_ID_CLASH, ///< Encountered clashing blank node IDs SERD_ERR_BAD_CURIE, ///< Invalid CURIE (e.g. prefix does not exist) SERD_ERR_INTERNAL, ///< Unexpected internal error (should not happen) SERD_ERR_OVERFLOW, ///< Stack overflow SERD_ERR_INVALID, ///< Invalid data SERD_ERR_NO_DATA ///< Unexpected end of input } SerdStatus; /// RDF syntax type typedef enum { SERD_TURTLE = 1, ///< Terse triples http://www.w3.org/TR/turtle SERD_NTRIPLES = 2, ///< Line-based triples http://www.w3.org/TR/n-triples/ SERD_NQUADS = 3, ///< Line-based quads http://www.w3.org/TR/n-quads/ SERD_TRIG = 4 ///< Terse quads http://www.w3.org/TR/trig/ } SerdSyntax; /// Flags indicating inline abbreviation information for a statement typedef enum { SERD_EMPTY_S = 1 << 0, ///< Empty blank node subject SERD_ANON_S = 1 << 1, ///< Start of anonymous subject SERD_ANON_O = 1 << 2, ///< Start of anonymous object SERD_LIST_S = 1 << 3, ///< Start of list subject SERD_LIST_O = 1 << 4, ///< Start of list object SERD_TERSE_S = 1 << 5, ///< Terse serialisation of new subject SERD_TERSE_O = 1 << 6 ///< Terse serialisation of new object } SerdStatementFlag; /// Bitwise OR of SerdStatementFlag values typedef uint32_t SerdStatementFlags; /// Flags that control style for a model serialisation typedef enum { SERD_NO_INLINE_OBJECTS = 1 << 0 ///< Disable object inlining } SerdSerialisationFlag; /// Bitwise OR of SerdStatementFlag values typedef uint32_t SerdSerialisationFlags; /** Type of a syntactic RDF node This is more precise than the type of an abstract RDF node. An abstract node is either a resource, literal, or blank. In syntax there are two ways to refer to a resource (by URI or CURIE) and two ways to refer to a blank (by ID or anonymously). Anonymous (inline) blank nodes are expressed using SerdStatementFlags rather than this type. */ typedef enum { /** Literal value A literal optionally has either a language, or a datatype (not both). */ SERD_LITERAL = 1, /** URI (absolute or relative) Value is an unquoted URI string, which is either a relative reference with respect to the current base URI (e.g. "foo/bar"), or an absolute URI (e.g. "http://example.org/foo"). @see [RFC3986](http://tools.ietf.org/html/rfc3986) */ SERD_URI = 2, /** CURIE, a shortened URI Value is an unquoted CURIE string relative to the current environment, e.g. "rdf:type". @see [CURIE Syntax 1.0](http://www.w3.org/TR/curie) */ SERD_CURIE = 3, /** A blank node Value is a blank node ID without any syntactic prefix, like "id3", which is meaningful only within this serialisation. @see [RDF 1.1 Turtle](http://www.w3.org/TR/turtle/#grammar-production-BLANK_NODE_LABEL) */ SERD_BLANK = 4 } SerdNodeType; /// Flags indicating certain string properties relevant to serialisation typedef enum { SERD_HAS_NEWLINE = 1, ///< Contains line breaks ('\\n' or '\\r') SERD_HAS_QUOTE = 1 << 1, ///< Contains quotes ('"') SERD_HAS_DATATYPE = 1 << 2, ///< Literal node has datatype SERD_HAS_LANGUAGE = 1 << 3 ///< Literal node has language } SerdNodeFlag; /// Bitwise OR of SerdNodeFlag values typedef uint32_t SerdNodeFlags; /// Field in a statement typedef enum { SERD_SUBJECT = 0, ///< Subject SERD_PREDICATE = 1, ///< Predicate ("key") SERD_OBJECT = 2, ///< Object ("value") SERD_GRAPH = 3 ///< Graph ("context") } SerdField; /// Indexing option typedef enum { SERD_INDEX_SPO = 1, ///< Subject, Predicate, Object SERD_INDEX_SOP = 1 << 1, ///< Subject, Object, Predicate SERD_INDEX_OPS = 1 << 2, ///< Object, Predicate, Subject SERD_INDEX_OSP = 1 << 3, ///< Object, Subject, Predicate SERD_INDEX_PSO = 1 << 4, ///< Predicate, Subject, Object SERD_INDEX_POS = 1 << 5, ///< Predicate, Object, Subject SERD_INDEX_GRAPHS = 1 << 6, ///< Support multiple graphs in model SERD_STORE_CURSORS = 1 << 7 ///< Store original cursor of statements } SerdModelFlag; /// Bitwise OR of SerdModelFlag values typedef uint32_t SerdModelFlags; /// A syntactic RDF node typedef struct SerdNodeImpl SerdNode; /// An unterminated immutable slice of a string typedef struct { const char* buf; ///< Start of chunk size_t len; ///< Length of chunk in bytes } SerdStringView; /// A mutable buffer in memory typedef struct { void* buf; ///< Buffer size_t len; ///< Size of buffer in bytes } SerdBuffer; /** A parsed URI This struct directly refers to slices in other strings, it does not own any memory itself. Thus, URIs can be parsed and/or resolved against a base URI in-place without allocating memory. */ typedef struct { SerdStringView scheme; ///< Scheme SerdStringView authority; ///< Authority SerdStringView path_base; ///< Path prefix if relative SerdStringView path; ///< Path suffix SerdStringView query; ///< Query SerdStringView fragment; ///< Fragment } SerdURI; /** Writer style options The style of the writer output can be controlled by ORing together values from this enumeration. Note that some options are only supported for some syntaxes (e.g. NTriples does not support abbreviation and is always ASCII). */ typedef enum { SERD_WRITE_ASCII = 1 << 0, ///< Escape all non-ASCII characters SERD_WRITE_TERSE = 1 << 1, ///< Write terser output without newlines } SerdWriterFlag; /// Bitwise OR of SerdWriterFlag values typedef uint32_t SerdWriterFlags; /** Free memory allocated by Serd This function exists because some systems require memory allocated by a library to be freed by code in the same library. It is otherwise equivalent to the standard C free() function. */ SERD_API void serd_free(void* ptr); /** @name String Utilities @{ */ /// Return a string describing a status code SERD_API const char* serd_strerror(SerdStatus status); /** Measure a UTF-8 string @return Length of `str` in bytes. @param str A null-terminated UTF-8 string. @param flags (Output) Set to the applicable flags. */ SERD_API size_t serd_strlen(const char* str, SerdNodeFlags* flags); /** Parse a string to a double The API of this function is similar to the standard C strtod function, except this function is locale-independent and always matches the lexical format used in the Turtle grammar (the decimal point is always "."). The end parameter is an offset from the start of `str` to avoid the const-correctness issues of the strtod API. */ SERD_API double serd_strtod(const char* str, size_t* end); /** @} @name Base64 @{ */ /** Return the number of bytes required to encode `size` bytes in base64 @param size The number of input (binary) bytes to encode. @param wrap_lines Wrap lines at 76 characters to conform to RFC 2045. @return The length of the base64 encoding, excluding null terminator. */ SERD_API size_t serd_base64_encoded_length(size_t size, bool wrap_lines); /** Return the maximum number of bytes required to decode `size` bytes of base64 @param len The number of input (text) bytes to decode. @return The required buffer size to decode `size` bytes of base64. */ SERD_API size_t serd_base64_decoded_size(size_t len); /** Encode `size` bytes of `buf` into `str`, which must be large enough @param str Output buffer of at least serd_base64_encoded_length(size) bytes. @param buf Input binary data. @param size Number of bytes to encode from `buf`. @param wrap_lines Wrap lines at 76 characters to conform to RFC 2045. @return True iff `str` contains newlines. */ SERD_API bool serd_base64_encode(char* str, const void* buf, size_t size, bool wrap_lines); /** Decode a base64 string This function can be used to deserialise a blob node created with serd_new_blob(). @param buf Output buffer of at least serd_base64_decoded_size(size) bytes. @param size Set to the size of the decoded data in bytes. @param str Base64 string to decode. @param len The length of `str`. */ SERD_API SerdStatus serd_base64_decode(void* buf, size_t* size, const char* str, size_t len); /** @} @name Byte Streams @{ */ /** Function to detect I/O stream errors Identical semantics to `ferror`. @return Non-zero if `stream` has encountered an error. */ typedef int (*SerdStreamErrorFunc)(void* stream); /** Source function for raw string input Identical semantics to `fread`, but may set errno for more informative error reporting than supported by SerdStreamErrorFunc. @param buf Output buffer. @param size Size of a single element of data in bytes (always 1). @param nmemb Number of elements to read. @param stream Stream to read from (FILE* for fread). @return Number of elements (bytes) read, which is short on error. */ typedef size_t (*SerdReadFunc)(void* buf, size_t size, size_t nmemb, void* stream); /** Sink function for raw string output Identical semantics to `fwrite`, but may set errno for more informative error reporting than supported by SerdStreamErrorFunc. @param buf Input buffer. @param size Size of a single element of data in bytes (always 1). @param nmemb Number of elements to read. @param stream Stream to write to (FILE* for fread). @return Number of elements (bytes) written, which is short on error. */ typedef size_t (*SerdWriteFunc)(const void* buf, size_t size, size_t nmemb, void* stream); /** Create a new byte sink @param write_func Function called with bytes to consume. @param stream Context parameter passed to `sink`. @param block_size Number of bytes to write per call. */ SERD_API SerdByteSink* serd_byte_sink_new(SerdWriteFunc write_func, void* stream, size_t block_size); /** Write to `sink` Compatible with SerdWriteFunc. */ SERD_API size_t serd_byte_sink_write(const void* buf, size_t size, size_t nmemb, SerdByteSink* sink); /// Flush any pending output in `sink` to the underlying write function SERD_API void serd_byte_sink_flush(SerdByteSink* sink); /// Free `sink` SERD_API void serd_byte_sink_free(SerdByteSink* sink); /** @} @name Syntax Utilities @{ */ /** Get a syntax by name Case-insensitive, supports "Turtle", "NTriples", "NQuads", and "TriG". Zero is returned if the name is not recognized. */ SERD_API SerdSyntax serd_syntax_by_name(const char* name); /** Guess a syntax from a filename This uses the file extension to guess the syntax of a file. Zero is returned if the extension is not recognized. */ SERD_API SerdSyntax serd_guess_syntax(const char* filename); /** Return whether a syntax can represent multiple graphs @return True for SERD_NQUADS and SERD_TRIG, false otherwise. */ SERD_API bool serd_syntax_has_graphs(SerdSyntax syntax); /** @} @name URI @{ */ static const SerdURI SERD_URI_NULL = { {NULL, 0}, {NULL, 0}, {NULL, 0}, {NULL, 0}, {NULL, 0}, {NULL, 0} }; /** Get the unescaped path and hostname from a file URI The returned path and `*hostname` must be freed with serd_free(). @param uri A file URI. @param hostname If non-NULL, set to the hostname, if present. @return The path component of the URI. */ SERD_API char* serd_file_uri_parse(const char* uri, char** hostname); /// Return true iff `utf8` starts with a valid URI scheme SERD_API bool serd_uri_string_has_scheme(const char* utf8); /// Parse `utf8`, writing result to `out` SERD_API SerdStatus serd_uri_parse(const char* utf8, SerdURI* out); /** Set target `t` to reference `r` resolved against `base` @see [RFC3986 5.2.2](http://tools.ietf.org/html/rfc3986#section-5.2.2) */ SERD_API void serd_uri_resolve(const SerdURI* r, const SerdURI* base, SerdURI* t); /// Serialise `uri` with a series of calls to `sink` SERD_API size_t serd_uri_serialise(const SerdURI* uri, SerdWriteFunc sink, void* stream); /** Serialise `uri` relative to `base` with a series of calls to `sink` The `uri` is written as a relative URI iff if it a child of `base` and `root`. The optional `root` parameter must be a prefix of `base` and can be used keep up-references ("../") within a certain namespace. */ SERD_API size_t serd_uri_serialise_relative(const SerdURI* uri, const SerdURI* base, const SerdURI* root, SerdWriteFunc sink, void* stream); /** @} @name Node @{ */ /** Create a new "simple" node that is just a string. This can be used to create blank, CURIE, or URI nodes from an already measured string or slice of a buffer, which avoids a strlen compared to the friendly constructors. This may not be used for literals since those must be measured to set the SERD_HAS_NEWLINE and SERD_HAS_QUOTE flags. */ SERD_API SerdNode* serd_new_simple_node(SerdNodeType type, const char* str, size_t len); /// Create a new plain literal string node from `str` SERD_API SerdNode* serd_new_string(const char* str); /// Create a new plain literal string node from a prefix of `str`. SERD_API SerdNode* serd_new_substring(const char* str, size_t len); /** Create a new literal node from substrings. This is a low-level constructor which can be used for constructing a literal from slices of a buffer (for example, directly from a Turtle literal) without copying. In most cases, applications should use the simpler serd_new_plain_literal() or serd_new_typed_literal(). Either `datatype_uri` or `lang` can be given, but not both, unless `datatype_uri` is rdf:langString in which case it is ignored. @param str Literal body string. @param str_len Length of `str` in bytes. @param datatype_uri Full datatype URI, or NULL. @param datatype_uri_len Length of `datatype_uri` in bytes. @param lang Language string. @param lang_len Length of `lang` in bytes. */ SERD_API SerdNode* serd_new_literal(const char* str, size_t str_len, const char* datatype_uri, size_t datatype_uri_len, const char* lang, size_t lang_len); /** Create a new plain literal node from `str` A plain literal has no datatype, but may have a language tag. The `lang` may be NULL, in which case this is equivalent to `serd_new_string()`. */ SERD_API SerdNode* serd_new_plain_literal(const char* str, const char* lang); /** Create a new typed literal node from `str` A typed literal has no language tag, but may have a datatype. The `datatype` may be NULL, in which case this is equivalent to `serd_new_string()`. */ SERD_API SerdNode* serd_new_typed_literal(const char* str, const SerdNode* datatype); /// Create a new blank node SERD_API SerdNode* serd_new_blank(const char* str); /// Create a new CURIE node SERD_API SerdNode* serd_new_curie(const char* str); /// Create a new URI from a string SERD_API SerdNode* serd_new_uri(const char* str); /// Create a new URI from a string, resolved against a base URI SERD_API SerdNode* serd_new_resolved_uri(const char* str, const SerdNode* base); /** Resolve `node` against `base` If `node` is not a relative URI, an equivalent new node is returned. */ SERD_API SerdNode* serd_node_resolve(const SerdNode* node, const SerdNode* base); /** Create a new file URI node from a file system path and optional hostname Backslashes in Windows paths will be converted, and other characters will be percent encoded as necessary. If `path` is relative, `hostname` is ignored. */ SERD_API SerdNode* serd_new_file_uri(const char* path, const char* hostname); /** Create a new URI from a string, relative to a base URI The URI is made relative iff if it a child of `base` and `root`. The optional `root` parameter must be a prefix of `base` and can be used keep up-references ("../") within a certain namespace. @param str URI string. @param base Base URI to make `str` relative to, if possible. @param root Optional root URI for resolution. */ SERD_API SerdNode* serd_new_relative_uri(const char* str, const SerdNode* base, const SerdNode* root); /** Create a new node by serialising `d` into an xsd:decimal string The resulting node will always contain a `.', start with a digit, and end with a digit (i.e. will have a leading and/or trailing `0' if necessary). It will never be in scientific notation. A maximum of `frac_digits` digits will be written after the decimal point, but trailing zeros will automatically be omitted (except one if `d` is a round integer). Note that about 16 and 8 fractional digits are required to precisely represent a double and float, respectively. @param d The value for the new node. @param frac_digits The maximum number of digits after the decimal place. @param datatype Datatype of node, or NULL for xsd:decimal. */ SERD_API SerdNode* serd_new_decimal(double d, unsigned frac_digits, const SerdNode* datatype); /** Create a new node by serialising `i` into an xsd:integer string @param i Integer value to serialise. @param datatype Datatype of node, or NULL for xsd:integer. */ SERD_API SerdNode* serd_new_integer(int64_t i, const SerdNode* datatype); /// Create a new node by serialising `b` into an xsd:boolean string SERD_API SerdNode* serd_new_boolean(bool b); /** Create a node by serialising `buf` into an xsd:base64Binary string This function can be used to make a serialisable node out of arbitrary binary data, which can be decoded using serd_base64_decode(). @param buf Raw binary input data. @param size Size of `buf`. @param wrap_lines Wrap lines at 76 characters to conform to RFC 2045. @param datatype Datatype of node, or NULL for xsd:base64Binary. */ SERD_API SerdNode* serd_new_blob(const void* buf, size_t size, bool wrap_lines, const SerdNode* datatype); /// Return a deep copy of `node` SERD_API SerdNode* serd_node_copy(const SerdNode* node); /// Free any data owned by `node` SERD_API void serd_node_free(SerdNode* node); /// Return the type of a node (SERD_URI, SERD_BLANK, or SERD_LITERAL). SERD_API SerdNodeType serd_node_get_type(const SerdNode* node); /// Return the string value of a node. SERD_API const char* serd_node_get_string(const SerdNode* node); /// Return the length of the string value of a node in bytes. SERD_API size_t serd_node_get_length(const SerdNode* node); /// Return the flags (string properties) of a node SERD_API SerdNodeFlags serd_node_get_flags(const SerdNode* node); /// Return the datatype of a literal node, or NULL. SERD_API const SerdNode* serd_node_get_datatype(const SerdNode* node); /// Return the language tag of a literal node, or NULL. SERD_API const SerdNode* serd_node_get_language(const SerdNode* node); /// Return true iff `a` is equal to `b` SERD_API bool serd_node_equals(const SerdNode* a, const SerdNode* b); /** Compare two nodes. Returns less than, equal to, or greater than zero if `a` is less than, equal to, or greater than `b`, respectively. NULL is treated as less than any other node. */ SERD_API int serd_node_compare(const SerdNode* a, const SerdNode* b); /** @} @name Event Handlers @{ */ /** Sink (callback) for base URI changes Called whenever the base URI of the serialisation changes. */ typedef SerdStatus (*SerdBaseFunc)(void* handle, const SerdNode* uri); /** Sink function for namespace definitions Called whenever a prefix is defined in the serialisation. */ typedef SerdStatus (*SerdPrefixFunc)(void* handle, const SerdNode* name, const SerdNode* uri); /** Sink function for statements Called for every RDF statement in the serialisation. */ typedef SerdStatus (*SerdStatementFunc)(void* handle, SerdStatementFlags flags, const SerdStatement* statement); /** Sink function for anonymous node end markers This is called to indicate that the anonymous node with the given `value` will no longer be referred to by any future statements (i.e. the anonymous serialisation of the node is finished). */ typedef SerdStatus (*SerdEndFunc)(void* handle, const SerdNode* node); /** @} @name World @{ */ /** Create a new World It is safe to use multiple worlds in one process, though no objects can be shared between worlds. */ SERD_API SerdWorld* serd_world_new(void); /// Free `world` SERD_API void serd_world_free(SerdWorld* world); /** Return the nodes cached in `world` The returned cache is owned by the world and contains various nodes used frequently by the implementation. For convenience, it may be used to store additional nodes which will be freed when the world is freed. */ SERD_API SerdNodes* serd_world_get_nodes(SerdWorld* world); /** Return a unique blank node The returned node is valid only until the next time serd_world_get_blank() is called or the world is destroyed. */ SERD_API const SerdNode* serd_world_get_blank(SerdWorld* world); /** @} @name Logging @{ */ /// Log message level, compatible with syslog typedef enum { SERD_LOG_LEVEL_EMERG, ///< Emergency, system is unusable SERD_LOG_LEVEL_ALERT, ///< Action must be taken immediately SERD_LOG_LEVEL_CRIT, ///< Critical condition SERD_LOG_LEVEL_ERR, ///< Error SERD_LOG_LEVEL_WARNING, ///< Warning SERD_LOG_LEVEL_NOTICE, ///< Normal but significant condition SERD_LOG_LEVEL_INFO, ///< Informational message SERD_LOG_LEVEL_DEBUG ///< Debug message } SerdLogLevel; /** A structured log field. This can be used to pass additional information along with log messages. Syslog-compatible keys should be used where possible, otherwise, keys should be namespaced to prevent clashes. Serd itself uses the following keys: - ERRNO - SERD_COL - SERD_FILE - SERD_LINE - SERD_STATUS */ typedef struct { const char* key; ///< Field name const char* value; ///< Field value } SerdLogField; /** A log entry (message). This is the description of a log entry which is passed to log functions. It is only valid in the stack frame it appears in, and may not be copied. */ typedef struct { const char* domain; ///< Message domain (library or program name) SerdLogLevel level; ///< Log level unsigned n_fields; ///< Number of entries in `fields` const SerdLogField* fields; ///< Extra log fields const char* fmt; ///< Format string (printf style) va_list* args; ///< Arguments corresponding to fmt } SerdLogEntry; /** Sink function for log messages. @param handle Handle for user data. @param entry Pointer to log entry description. */ typedef SerdStatus (*SerdLogFunc)(void* handle, const SerdLogEntry* entry); /// A SerdLogFunc that does nothing, for suppressing log output SERD_API SerdStatus serd_quiet_error_func(void* handle, const SerdLogEntry* entry); /// Return the value of the log field named `key`, or NULL if none exists SERD_API const char* serd_log_entry_get_field(const SerdLogEntry* entry, const char* key); /** Set a function to be called with log messages (typically errors). The `log_func` will be called with `handle` as its first argument. If no function is set, messages are printed to stderr. */ SERD_API void serd_world_set_log_func(SerdWorld* world, SerdLogFunc log_func, void* handle); /// Write a message to the log SERD_API SERD_LOG_FUNC(6, 0) SerdStatus serd_world_vlogf(const SerdWorld* world, const char* domain, SerdLogLevel level, unsigned n_fields, const SerdLogField* fields, const char* fmt, va_list args); /// Write a message to the log SERD_API SERD_LOG_FUNC(6, 7) SerdStatus serd_world_logf(const SerdWorld* world, const char* domain, SerdLogLevel level, unsigned n_fields, const SerdLogField* fields, const char* fmt, ...); /** @} @name Environment @{ */ /// Create a new environment SERD_API SerdEnv* serd_env_new(const SerdNode* base_uri); /// Copy an environment SERD_API SerdEnv* serd_env_copy(const SerdEnv* env); /// Return true iff `a` is equal to `b` SERD_API bool serd_env_equals(const SerdEnv* a, const SerdEnv* b); /// Free `env` SERD_API void serd_env_free(SerdEnv* env); /// Get the current base URI SERD_API const SerdNode* serd_env_get_base_uri(const SerdEnv* env); /// Set the current base URI SERD_API SerdStatus serd_env_set_base_uri(SerdEnv* env, const SerdNode* uri); /// Set a namespace prefix SERD_API SerdStatus serd_env_set_prefix(SerdEnv* env, const SerdNode* name, const SerdNode* uri); /// Set a namespace prefix SERD_API SerdStatus serd_env_set_prefix_from_strings(SerdEnv* env, const char* name, const char* uri); /** Qualify `uri` into a CURIE if possible Returns null if `node` can not be qualified. */ SERD_API SerdNode* serd_env_qualify(const SerdEnv* env, const SerdNode* uri); /** Expand `node`, transforming CURIEs into URIs If `node` is a literal, its datatype is expanded if necessary. Returns null if `node` can not be expanded. */ SERD_API SerdNode* serd_env_expand(const SerdEnv* env, const SerdNode* node); /// Write all prefixes in `env` to `sink` SERD_API void serd_env_write_prefixes(const SerdEnv* env, const SerdSink* sink); /** @} @name Sink @{ */ /** Create a new sink Initially, the sink has no set functions and will do nothing. Use the serd_sink_set_*_func functions to set handlers for various events. @param handle Opaque handle that will be passed to sink functions. @param env Environment for sink, updated as base uri or prefixes change. */ SERD_API SerdSink* serd_sink_new(void* handle, SerdEnv* env); /// Free `sink` SERD_API void serd_sink_free(SerdSink* sink); /// Return the env used by `sink` SERD_API const SerdEnv* serd_sink_get_env(const SerdSink* sink); /// Set a function to be called when the base URI changes SERD_API SerdStatus serd_sink_set_base_func(SerdSink* sink, SerdBaseFunc base_func); /// Set a function to be called when a namespace prefix is defined SERD_API SerdStatus serd_sink_set_prefix_func(SerdSink* sink, SerdPrefixFunc prefix_func); /// Set a function to be called when a statement is emitted SERD_API SerdStatus serd_sink_set_statement_func(SerdSink* sink, SerdStatementFunc statement_func); /// Set a function to be called when an anonymous node ends SERD_API SerdStatus serd_sink_set_end_func(SerdSink* sink, SerdEndFunc end_func); /// Set the base URI SERD_API SerdStatus serd_sink_write_base(const SerdSink* sink, const SerdNode* uri); /// Set a namespace prefix SERD_API SerdStatus serd_sink_write_prefix(const SerdSink* sink, const SerdNode* name, const SerdNode* uri); /// Write a statement SERD_API SerdStatus serd_sink_write_statement(const SerdSink* sink, SerdStatementFlags flags, const SerdStatement* statement); /// Write a statement from individual nodes SERD_API SerdStatus serd_sink_write(const SerdSink* sink, SerdStatementFlags flags, const SerdNode* subject, const SerdNode* predicate, const SerdNode* object, const SerdNode* graph); /// Mark the end of an anonymous node SERD_API SerdStatus serd_sink_write_end(const SerdSink* sink, const SerdNode* node); /** @} @name Reader @{ */ /// Create a new RDF reader SERD_API SerdReader* serd_reader_new(SerdWorld* world, SerdSyntax syntax, const SerdSink* sink, size_t stack_size); /** Enable or disable strict parsing The reader is non-strict (lax) by default, which will tolerate URIs with invalid characters. Setting strict will fail when parsing such files. An error is printed for invalid input in either case. */ SERD_API void serd_reader_set_strict(SerdReader* reader, bool strict); /** Set a prefix to be added to all blank node identifiers This is useful when multiple files are to be parsed into the same output (e.g. a store, or other files). Since Serd preserves blank node IDs, this could cause conflicts where two non-equivalent blank nodes are merged, resulting in corrupt data. By setting a unique blank node prefix for each parsed file, this can be avoided, while preserving blank node names. */ SERD_API void serd_reader_add_blank_prefix(SerdReader* reader, const char* prefix); /// Prepare to read from the file at a local file `uri` SERD_API SerdStatus serd_reader_start_file(SerdReader* reader, const char* uri, bool bulk); /** Prepare to read from a stream The `read_func` is guaranteed to only be called for `page_size` elements with size 1 (i.e. `page_size` bytes). */ SERD_API SerdStatus serd_reader_start_stream(SerdReader* reader, SerdReadFunc read_func, SerdStreamErrorFunc error_func, void* stream, const SerdNode* name, size_t page_size); /// Prepare to read from a string SERD_API SerdStatus serd_reader_start_string(SerdReader* reader, const char* utf8, const SerdNode* name); /** Read a single "chunk" of data during an incremental read This function will read a single top level description, and return. This may be a directive, statement, or several statements; essentially it reads until a '.' is encountered. This is particularly useful for reading directly from a pipe or socket. */ SERD_API SerdStatus serd_reader_read_chunk(SerdReader* reader); /** Read a complete document from the source This function will continue pulling from the source until a complete document has been read. Note that this may block when used with streams, for incremental reading use serd_reader_read_chunk(). */ SERD_API SerdStatus serd_reader_read_document(SerdReader* reader); /** Finish reading from the source This will close the open file, if applicable, and ensure the reader has processed all input. */ SERD_API SerdStatus serd_reader_finish(SerdReader* reader); /** Free `reader` The reader will be finished via `serd_reader_finish()` if necessary. */ SERD_API void serd_reader_free(SerdReader* reader); /** @} @name Writer @{ */ /// Create a new RDF writer SERD_API SerdWriter* serd_writer_new(SerdWorld* world, SerdSyntax syntax, SerdWriterFlags flags, SerdEnv* env, SerdWriteFunc write_func, void* stream); /// Free `writer` SERD_API void serd_writer_free(SerdWriter* writer); /// Return a sink interface that emits statements via `writer` SERD_API const SerdSink* serd_writer_get_sink(SerdWriter* writer); /** A convenience sink function for writing to a string This function can be used as a SerdSink to write to a SerdBuffer which is resized as necessary with realloc(). The `stream` parameter must point to an initialized SerdBuffer. When the write is finished, the string should be retrieved with serd_buffer_sink_finish(). */ SERD_API size_t serd_buffer_sink(const void* buf, size_t size, size_t nmemb, void* stream); /** Finish a serialisation to a buffer with serd_buffer_sink() The returned string is the result of the serialisation, which is null terminated (by this function) and owned by the caller. */ SERD_API char* serd_buffer_sink_finish(SerdBuffer* stream); /// Set a prefix to be removed from matching blank node identifiers SERD_API void serd_writer_chop_blank_prefix(SerdWriter* writer, const char* prefix); /** Set the current output base URI (and emit directive if applicable) Note this function can be safely casted to SerdBaseSink. */ SERD_API SerdStatus serd_writer_set_base_uri(SerdWriter* writer, const SerdNode* uri); /** Set the current root URI The root URI should be a prefix of the base URI. The path of the root URI is the highest path any relative up-reference can refer to. For example, with root and base , will be written as <../>, but will be written non-relatively as . If the root is not explicitly set, it defaults to the base URI, so no up-references will be created at all. */ SERD_API SerdStatus serd_writer_set_root_uri(SerdWriter* writer, const SerdNode* uri); /// Finish a write SERD_API SerdStatus serd_writer_finish(SerdWriter* writer); /** @} @name Nodes @{ */ /// Create a new node set SERD_API SerdNodes* serd_nodes_new(void); /** Free `nodes` and all nodes that are stored in it Note that this invalidates any pointers previously returned from `serd_nodes_intern()` or `serd_nodes_manage()` calls on `nodes`. */ SERD_API void serd_nodes_free(SerdNodes* nodes); /** Intern `node` Multiple calls with equivalent nodes will return the same pointer. @return A node that is different than, but equivalent to, `node`. */ SERD_API const SerdNode* serd_nodes_intern(SerdNodes* nodes, const SerdNode* node); /** Manage `node` Like `serd_nodes_intern`, but takes ownership of `node`, freeing it and returning a previously interned/managed equivalent node if necessary. @return A node that is equivalent to `node`. */ SERD_API const SerdNode* serd_nodes_manage(SerdNodes* nodes, SerdNode* node); /** Dereference `node` Decrements the reference count of `node`, and frees the internally stored equivalent node if this was the last reference. Does nothing if no node equivalent to `node` is stored in `nodes`. */ SERD_API void serd_nodes_deref(SerdNodes* nodes, const SerdNode* node); /** @} @name Model @{ */ /** Create a new model @param world The world in which to make this model. @param flags Model options, including enabled indices, for example `SERD_SPO | SERD_OPS`. Be sure to enable an index where the most significant node(s) are not variables in your queries. For example, to make (? P O) queries, enable either SERD_OPS or SERD_POS. */ SERD_API SerdModel* serd_model_new(SerdWorld* world, SerdModelFlags flags); /// Return a deep copy of `model` SERD_API SerdModel* serd_model_copy(const SerdModel* model); /// Return true iff `a` is equal to `b`, ignoring statement cursor metadata SERD_API bool serd_model_equals(const SerdModel* a, const SerdModel* b); /// Close and free `model` SERD_API void serd_model_free(SerdModel* model); /// Get the world associated with `model` SERD_API SerdWorld* serd_model_get_world(SerdModel* model); /// Get the flags enabled on `model` SERD_API SerdModelFlags serd_model_get_flags(const SerdModel* model); /// Return the number of statements stored in `model` SERD_API size_t serd_model_size(const SerdModel* model); /// Return true iff there are no statements stored in `model` SERD_API bool serd_model_empty(const SerdModel* model); /// Return an iterator to the start of `model` SERD_API SerdIter* serd_model_begin(const SerdModel* model); /// Return an iterator to the end of `model` SERD_API const SerdIter* serd_model_end(const SerdModel* model); /// Return a range of all statements in `model` SERD_API SerdRange* serd_model_all(const SerdModel* model); /** Search for statements by a quad pattern @return An iterator to the first match, or NULL if no matches found. */ SERD_API SerdIter* serd_model_find(const SerdModel* model, const SerdNode* s, const SerdNode* p, const SerdNode* o, const SerdNode* g); /** Search for statements by a quad pattern @return A range containing all matching statements. */ SERD_API SerdRange* serd_model_range(const SerdModel* model, const SerdNode* s, const SerdNode* p, const SerdNode* o, const SerdNode* g); /** Search for a single node that matches a pattern Exactly one of `s`, `p`, `o` must be NULL. This function is mainly useful for predicates that only have one value. @return The first matching node, or NULL if no matches are found. */ SERD_API const SerdNode* serd_model_get(const SerdModel* model, const SerdNode* s, const SerdNode* p, const SerdNode* o, const SerdNode* g); /** Search for a single statement that matches a pattern This function is mainly useful for predicates that only have one value. @return The first matching statement, or NULL if none are found. */ SERD_API const SerdStatement* serd_model_get_statement(const SerdModel* model, const SerdNode* s, const SerdNode* p, const SerdNode* o, const SerdNode* g); /// Return true iff a statement exists SERD_API bool serd_model_ask(const SerdModel* model, const SerdNode* s, const SerdNode* p, const SerdNode* o, const SerdNode* g); /// Return the number of matching statements SERD_API size_t serd_model_count(const SerdModel* model, const SerdNode* s, const SerdNode* p, const SerdNode* o, const SerdNode* g); /** Add a statement to a model from nodes This function fails if there are any active iterators on `model`. */ SERD_API SerdStatus serd_model_add(SerdModel* model, const SerdNode* s, const SerdNode* p, const SerdNode* o, const SerdNode* g); /** Add a statement to a model This function fails if there are any active iterators on `model`. */ SERD_API SerdStatus serd_model_insert(SerdModel* model, const SerdStatement* statement); /** Add a range of statements to a model This function fails if there are any active iterators on `model`. */ SERD_API SerdStatus serd_model_add_range(SerdModel* model, SerdRange* range); /** Remove a quad from a model via an iterator Calling this function invalidates all iterators on `model` except `iter`. @param model The model which `iter` points to. @param iter Iterator to the element to erase, which is incremented to the next value on return. */ SERD_API SerdStatus serd_model_erase(SerdModel* model, SerdIter* iter); /** Remove a range from a model Calling this function invalidates all iterators on `model` except `iter`. @param model The model which `range` points to. @param range Range to erase, which will be empty on return; */ SERD_API SerdStatus serd_model_erase_range(SerdModel* model, SerdRange* range); /** Validate model. This performs validation based on the RDFS and OWL vocabularies. All necessary data, including those vocabularies and any property/class definitions that use them, are assumed to be in `model`. Validation errors are reported to the world's error sink. @return 0 on success. */ SERD_API SerdStatus serd_validate(const SerdModel* model); /** @} @name Inserter @{ */ /// Create an inserter for writing statements to a model SERD_API SerdInserter* serd_inserter_new(SerdModel* model, SerdEnv* env, const SerdNode* default_graph); /// Free an inserter SERD_API void serd_inserter_free(SerdInserter* inserter); /// Return a sink interface that adds statements via `inserter` SERD_API const SerdSink* serd_inserter_get_sink(SerdInserter* inserter); /** @} @name Statement @{ */ /** Create a new statement Note that, to minimise model overhead, statements do not own their nodes, so they must have a longer lifetime than the statement for it to be valid. For statements in models, this is the lifetime of the model. For user-created statements, the simplest way to handle this is to use `SerdNodes`. @param s The subject @param p The predicate ("key") @param o The object ("value") @param g The graph ("context") @param cursor Optional cursor at the origin of this statement @return A new statement that must be freed with serd_statement_free() */ SERD_API SerdStatement* serd_statement_new(const SerdNode* s, const SerdNode* p, const SerdNode* o, const SerdNode* g, const SerdCursor* cursor); /// Return a copy of `statement` SERD_API SerdStatement* serd_statement_copy(const SerdStatement* statement); /// Free `statement` SERD_API void serd_statement_free(SerdStatement* statement); /// Return the given node in `statement` SERD_API const SerdNode* serd_statement_get_node(const SerdStatement* statement, SerdField field); /// Return the subject in `statement` SERD_API const SerdNode* serd_statement_get_subject(const SerdStatement* statement); /// Return the predicate in `statement` SERD_API const SerdNode* serd_statement_get_predicate(const SerdStatement* statement); /// Return the object in `statement` SERD_API const SerdNode* serd_statement_get_object(const SerdStatement* statement); /// Return the graph in `statement` SERD_API const SerdNode* serd_statement_get_graph(const SerdStatement* statement); /// Return the source location where `statement` originated, or NULL SERD_API const SerdCursor* serd_statement_get_cursor(const SerdStatement* statement); /** Return true iff `a` is equal to `b`, ignoring statement cursor metadata Only returns true if nodes are equivalent, does not perform wildcard matching. */ SERD_API bool serd_statement_equals(const SerdStatement* a, const SerdStatement* b); /** Return true iff `statement` matches the given pattern The matching rules are the same used for querying: nodes match if they are equivalent, and NULL acts as a wildcard that matches any node. */ SERD_API bool serd_statement_matches(const SerdStatement* statement, const SerdNode* subject, const SerdNode* predicate, const SerdNode* object, const SerdNode* graph); /** @} @name Iterator @{ */ /// Return a new copy of `iter` SERD_API SerdIter* serd_iter_copy(const SerdIter* iter); /// Return the statement pointed to by `iter` SERD_API const SerdStatement* serd_iter_get(const SerdIter* iter); /** Increment `iter` to point to the next statement @return True iff `iter` has reached the end. */ SERD_API bool serd_iter_next(SerdIter* iter); /// Return true iff `lhs` is equal to `rhs` SERD_API bool serd_iter_equals(const SerdIter* lhs, const SerdIter* rhs); /// Free `iter` SERD_API void serd_iter_free(SerdIter* iter); /** @} @name Range @{ */ /// Return a new copy of `range` SERD_API SerdRange* serd_range_copy(const SerdRange* range); /// Free `range` SERD_API void serd_range_free(SerdRange* range); /// Return the first statement in `range`, or NULL if `range` is empty SERD_API const SerdStatement* serd_range_front(const SerdRange* range); /// Return true iff `lhs` is equal to `rhs` SERD_API bool serd_range_equals(const SerdRange* lhs, const SerdRange* rhs); /// Increment the start of `range` to point to the next statement SERD_API bool serd_range_next(SerdRange* range); /// Return true iff there are no statements in `range` SERD_API bool serd_range_empty(const SerdRange* range); /// Return an iterator to the start of `range` SERD_API const SerdIter* serd_range_cbegin(const SerdRange* range); /// Return an iterator to the end of `range` SERD_API const SerdIter* serd_range_cend(const SerdRange* range); /// Return an iterator to the start of `range` SERD_API SerdIter* serd_range_begin(SerdRange* range); /// Return an iterator to the end of `range` SERD_API SerdIter* serd_range_end(SerdRange* range); /** Write `range` to `sink` The serialisation style can be controlled with `flags`. The default is to write statements in an order suited for pretty-printing with Turtle or TriG with as many objects written inline as possible. If `SERD_NO_INLINE_OBJECTS` is given, a simple sorted stream is written instead, which is significantly faster since no searching is required, but can result in ugly output for Turtle or Trig. */ SERD_API SerdStatus serd_range_serialise(const SerdRange* range, const SerdSink* sink, SerdSerialisationFlags flags); /** @} @name Cursor @{ */ /** Create a new cursor Note that, to minimise model overhead, the cursor does not own the name node, so `name` must have a longer lifetime than the cursor for it to be valid. That is, serd_cursor_get_name() will return exactly the pointer `name`, not a copy. For cursors from models, this is the lifetime of the model. For user-created cursors, the simplest way to handle this is to use `SerdNodes`. @param name The name of the document or stream (usually a file URI) @param line The line number in the document (1-based) @param col The column number in the document (1-based) @return A new cursor that must be freed with serd_cursor_free() */ SERD_API SerdCursor* serd_cursor_new(const SerdNode* name, unsigned line, unsigned col); /// Return a copy of `cursor` SERD_API SerdCursor* serd_cursor_copy(const SerdCursor* cursor); /// Free `cursor` SERD_API void serd_cursor_free(SerdCursor* cursor); /// Return true iff `lhs` is equal to `rhs` SERD_API bool serd_cursor_equals(const SerdCursor* lhs, const SerdCursor* rhs); /** Return the document name This is typically a file URI, but may be a descriptive string node for statements that originate from streams. */ SERD_API const SerdNode* serd_cursor_get_name(const SerdCursor* cursor); /// Return the one-relative line number in the document SERD_API unsigned serd_cursor_get_line(const SerdCursor* cursor); /// Return the zero-relative column number in the line SERD_API unsigned serd_cursor_get_column(const SerdCursor* cursor); /** @} @} */ #ifdef __cplusplus } /* extern "C" */ #endif #endif /* SERD_SERD_H */