1 files changed, 110 insertions, 0 deletions
diff --git a/src/include/utils/jsonapi.h b/src/include/utils/jsonapi.h
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+++ b/src/include/utils/jsonapi.h
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+/*-------------------------------------------------------------------------
+ *
+ * jsonapi.h
+ *	  Declarations for JSON API support.
+ *
+ * Portions Copyright (c) 1996-2013, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/include/utils/jsonapi.h
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#ifndef JSONAPI_H
+#define JSONAPI_H
+
+#include "lib/stringinfo.h"
+
+typedef enum
+{
+	JSON_TOKEN_INVALID,
+	JSON_TOKEN_STRING,
+	JSON_TOKEN_NUMBER,
+	JSON_TOKEN_OBJECT_START,
+	JSON_TOKEN_OBJECT_END,
+	JSON_TOKEN_ARRAY_START,
+	JSON_TOKEN_ARRAY_END,
+	JSON_TOKEN_COMMA,
+	JSON_TOKEN_COLON,
+	JSON_TOKEN_TRUE,
+	JSON_TOKEN_FALSE,
+	JSON_TOKEN_NULL,
+	JSON_TOKEN_END,
+}	JsonTokenType;
+
+
+/*
+ * All the fields in this structure should be treated as read-only.
+ *
+ * If strval is not null, then it should contain the de-escaped value
+ * of the lexeme if it's a string. Otherwise most of these field names
+ * should be self-explanatory.
+ *
+ * line_number and line_start are principally for use by the parser's
+ * error reporting routines.
+ * token_terminator and prev_token_terminator point to the character
+ * AFTER the end of the token, i.e. where there would be a nul byte
+ * if we were using nul-terminated strings.
+ */
+typedef struct JsonLexContext
+{
+	char	   *input;
+	int			input_length;
+	char	   *token_start;
+	char	   *token_terminator;
+	char	   *prev_token_terminator;
+	JsonTokenType token_type;
+	int			lex_level;
+	int			line_number;
+	char	   *line_start;
+	StringInfo	strval;
+} JsonLexContext;
+
+typedef void (*json_struct_action) (void *state);
+typedef void (*json_ofield_action) (void *state, char *fname, bool isnull);
+typedef void (*json_aelem_action) (void *state, bool isnull);
+typedef void (*json_scalar_action) (void *state, char *token, JsonTokenType tokentype);
+
+
+/*
+ * Semantic Action structure for use in parsing json.
+ * Any of these actions can be NULL, in which case nothing is done at that
+ * point, Likewise, semstate can be NULL. Using an all-NULL structure amounts
+ * to doing a pure parse with no side-effects, and is therefore exactly
+ * what the json input routines do.
+ */
+typedef struct jsonSemAction
+{
+	void	   *semstate;
+	json_struct_action object_start;
+	json_struct_action object_end;
+	json_struct_action array_start;
+	json_struct_action array_end;
+	json_ofield_action object_field_start;
+	json_ofield_action object_field_end;
+	json_aelem_action array_element_start;
+	json_aelem_action array_element_end;
+	json_scalar_action scalar;
+}	jsonSemAction, *JsonSemAction;
+
+/*
+ * parse_json will parse the string in the lex calling the
+ * action functions in sem at the appropriate points. It is
+ * up to them to keep what state they need	in semstate. If they
+ * need access to the state of the lexer, then its pointer
+ * should be passed to them as a member of whatever semstate
+ * points to. If the action pointers are NULL the parser
+ * does nothing and just continues.
+ */
+extern void pg_parse_json(JsonLexContext *lex, JsonSemAction sem);
+
+/*
+ * constructor for JsonLexContext, with or without strval element.
+ * If supplied, the strval element will contain a de-escaped version of
+ * the lexeme. However, doing this imposes a performance penalty, so
+ * it should be avoided if the de-escaped lexeme is not required.
+ */
+extern JsonLexContext *makeJsonLexContext(text *json, bool need_escapes);
+
+#endif   /* JSONAPI_H */