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+/*
+ * Copyright (c) 2007-2014, Lloyd Hilaiel <me@lloyd.io>
+ *
+ * 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.
+ *
+ * THE 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 yajl_parse.h
+ * Interface to YAJL's JSON stream parsing facilities.
+ */
+
+#include "yajl_common.h"
+
+#ifndef __YAJL_PARSE_H__
+#define __YAJL_PARSE_H__
+
+#include <stddef.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+ /** error codes returned from this interface */
+ typedef enum {
+ /** no error was encountered */
+ yajl_status_ok,
+ /** a client callback returned zero, stopping the parse */
+ yajl_status_client_canceled,
+ /** An error occured during the parse. Call yajl_get_error for
+ * more information about the encountered error */
+ yajl_status_error
+ } yajl_status;
+
+ /** attain a human readable, english, string for an error */
+ YAJL_API const char * yajl_status_to_string(yajl_status code);
+
+ /** an opaque handle to a parser */
+ typedef struct yajl_handle_t * yajl_handle;
+
+ /** yajl is an event driven parser. this means as json elements are
+ * parsed, you are called back to do something with the data. The
+ * functions in this table indicate the various events for which
+ * you will be called back. Each callback accepts a "context"
+ * pointer, this is a void * that is passed into the yajl_parse
+ * function which the client code may use to pass around context.
+ *
+ * All callbacks return an integer. If non-zero, the parse will
+ * continue. If zero, the parse will be canceled and
+ * yajl_status_client_canceled will be returned from the parse.
+ *
+ * \attention {
+ * A note about the handling of numbers:
+ *
+ * yajl will only convert numbers that can be represented in a
+ * double or a 64 bit (longlong) int. All other numbers will
+ * be passed to the client in string form using the yajl_number
+ * callback. Furthermore, if yajl_number is not NULL, it will
+ * always be used to return numbers, that is yajl_integer and
+ * yajl_double will be ignored. If yajl_number is NULL but one
+ * of yajl_integer or yajl_double are defined, parsing of a
+ * number larger than is representable in a double or 64 bit
+ * integer will result in a parse error.
+ * }
+ */
+ typedef struct {
+ int (* yajl_null)(void * ctx);
+ int (* yajl_boolean)(void * ctx, int boolVal);
+ int (* yajl_integer)(void * ctx, longlong integerVal);
+ int (* yajl_double)(void * ctx, double doubleVal);
+ /** A callback which passes the string representation of the number
+ * back to the client. Will be used for all numbers when present */
+ int (* yajl_number)(void * ctx, const char * numberVal,
+ size_t numberLen);
+
+ /** strings are returned as pointers into the JSON text when,
+ * possible, as a result, they are _not_ null padded */
+ int (* yajl_string)(void * ctx, const unsigned char * stringVal,
+ size_t stringLen);
+
+ int (* yajl_c_comment)(void * ctx, const unsigned char * stringVal,
+ unsigned int stringLen);
+
+ int (* yajl_cpp_comment)(void * ctx, const unsigned char * stringVal,
+ unsigned int stringLen);
+
+ int (* yajl_start_map)(void * ctx);
+ int (* yajl_map_key)(void * ctx, const unsigned char * key,
+ size_t stringLen);
+ int (* yajl_end_map)(void * ctx);
+
+ int (* yajl_start_array)(void * ctx);
+ int (* yajl_end_array)(void * ctx);
+ } yajl_callbacks;
+
+ /** allocate a parser handle
+ * \param callbacks a yajl callbacks structure specifying the
+ * functions to call when different JSON entities
+ * are encountered in the input text. May be NULL,
+ * which is only useful for validation.
+ * \param afs memory allocation functions, may be NULL for to use
+ * C runtime library routines (malloc and friends)
+ * \param ctx a context pointer that will be passed to callbacks.
+ */
+ YAJL_API yajl_handle yajl_alloc(const yajl_callbacks * callbacks,
+ yajl_alloc_funcs * afs,
+ void * ctx);
+
+
+ /** configuration parameters for the parser, these may be passed to
+ * yajl_config() along with option specific argument(s). In general,
+ * all configuration parameters default to *off*. */
+ typedef enum {
+ /** Ignore javascript style comments present in
+ * JSON input. Non-standard, but rather fun
+ * arguments: toggled off with integer zero, on otherwise.
+ *
+ * example:
+ * yajl_config(h, yajl_allow_comments, 1); // turn comment support on
+ */
+ yajl_allow_comments = 0x01,
+ /**
+ * When set the parser will verify that all strings in JSON input are
+ * valid UTF8 and will emit a parse error if this is not so. When set,
+ * this option makes parsing slightly more expensive (~7% depending
+ * on processor and compiler in use)
+ *
+ * example:
+ * yajl_config(h, yajl_dont_validate_strings, 1); // disable utf8 checking
+ */
+ yajl_dont_validate_strings = 0x02,
+ /**
+ * By default, upon calls to yajl_complete_parse(), yajl will
+ * ensure the entire input text was consumed and will raise an error
+ * otherwise. Enabling this flag will cause yajl to disable this
+ * check. This can be useful when parsing json out of a that contains more
+ * than a single JSON document.
+ */
+ yajl_allow_trailing_garbage = 0x04,
+ /**
+ * Allow multiple values to be parsed by a single handle. The
+ * entire text must be valid JSON, and values can be seperated
+ * by any kind of whitespace. This flag will change the
+ * behavior of the parser, and cause it continue parsing after
+ * a value is parsed, rather than transitioning into a
+ * complete state. This option can be useful when parsing multiple
+ * values from an input stream.
+ */
+ yajl_allow_multiple_values = 0x08,
+ /**
+ * When yajl_complete_parse() is called the parser will
+ * check that the top level value was completely consumed. I.E.,
+ * if called whilst in the middle of parsing a value
+ * yajl will enter an error state (premature EOF). Setting this
+ * flag suppresses that check and the corresponding error.
+ */
+ yajl_allow_partial_values = 0x10
+ } yajl_option;
+
+ /** allow the modification of parser options subsequent to handle
+ * allocation (via yajl_alloc)
+ * \returns zero in case of errors, non-zero otherwise
+ */
+ YAJL_API int yajl_config(yajl_handle h, yajl_option opt, ...);
+
+ /** free a parser handle */
+ YAJL_API void yajl_free(yajl_handle handle);
+
+ /** Parse some json!
+ * \param hand - a handle to the json parser allocated with yajl_alloc
+ * \param jsonText - a pointer to the UTF8 json text to be parsed
+ * \param jsonTextLength - the length, in bytes, of input text
+ */
+ YAJL_API yajl_status yajl_parse(yajl_handle hand,
+ const unsigned char * jsonText,
+ size_t jsonTextLength);
+
+ /** Parse any remaining buffered json.
+ * Since yajl is a stream-based parser, without an explicit end of
+ * input, yajl sometimes can't decide if content at the end of the
+ * stream is valid or not. For example, if "1" has been fed in,
+ * yajl can't know whether another digit is next or some character
+ * that would terminate the integer token.
+ *
+ * \param hand - a handle to the json parser allocated with yajl_alloc
+ */
+ YAJL_API yajl_status yajl_complete_parse(yajl_handle hand);
+
+ /** get an error string describing the state of the
+ * parse.
+ *
+ * If verbose is non-zero, the message will include the JSON
+ * text where the error occured, along with an arrow pointing to
+ * the specific char.
+ *
+ * \returns A dynamically allocated string will be returned which should
+ * be freed with yajl_free_error
+ */
+ YAJL_API unsigned char * yajl_get_error(yajl_handle hand, int verbose,
+ const unsigned char * jsonText,
+ size_t jsonTextLength);
+
+ /**
+ * get the amount of data consumed from the last chunk passed to YAJL.
+ *
+ * In the case of a successful parse this can help you understand if
+ * the entire buffer was consumed (which will allow you to handle
+ * "junk at end of input").
+ *
+ * In the event an error is encountered during parsing, this function
+ * affords the client a way to get the offset into the most recent
+ * chunk where the error occured. 0 will be returned if no error
+ * was encountered.
+ */
+ YAJL_API size_t yajl_get_bytes_consumed(yajl_handle hand);
+
+ /** free an error returned from yajl_get_error */
+ YAJL_API void yajl_free_error(yajl_handle hand, unsigned char * str);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif