scanner.h

一个开源SIP协议栈

 * of PJ_SCAN_AUTOSKIP_WS settings. If the character left is less than len, 
 * syntax error callback will be called.
 *
 * @param scanner   The scanner.
 * @param len	    Length to peek.
 * @param out	    String to store the result.
 *
 * @return the character right after the peek-ed position or zero if there's
 *	   no more characters.
 */
PJ_DECL(int) pj_scan_peek_n( pj_scanner *scanner,
			     pj_size_t len, pj_str_t *out);


/** 
 * Peek strings in current position until spec is matched, and return
 * the strings in parameter out. The current scanner position will not be
 * moved. If the scanner is already in EOF state, syntax error callback will
 * be called.
 *
 * @param scanner   The scanner.
 * @param spec	    The peeking will stop when the input match this spec.
 * @param out	    String to store the result.
 *
 * @return the character right after the peek-ed position.
 */
PJ_DECL(int) pj_scan_peek_until( pj_scanner *scanner,
				 const pj_cis_t *spec, 
				 pj_str_t *out);


/** 
 * Get characters from the buffer according to the spec, and return them
 * in out parameter. The scanner will attempt to get as many characters as
 * possible as long as the spec matches. If the first character doesn't
 * match the spec, or scanner is already in EOF when this function is called,
 * an exception will be thrown.
 *
 * @param scanner   The scanner.
 * @param spec	    The spec to match input string.
 * @param out	    String to store the result.
 */
PJ_DECL(void) pj_scan_get( pj_scanner *scanner,
			   const pj_cis_t *spec, pj_str_t *out);


/** 
 * Just like #pj_scan_get(), but additionally performs unescaping when
 * escaped ('%') character is found. The input spec MUST NOT contain the
 * specification for '%' characted.
 *
 * @param scanner   The scanner.
 * @param spec	    The spec to match input string.
 * @param out	    String to store the result.
 */
PJ_DECL(void) pj_scan_get_unescape( pj_scanner *scanner,
				    const pj_cis_t *spec, pj_str_t *out);


/** 
 * Get characters between quotes. If current input doesn't match begin_quote,
 * syntax error will be thrown. Note that the resulting string will contain
 * the enclosing quote.
 *
 * @param scanner	The scanner.
 * @param begin_quote	The character to begin the quote.
 * @param end_quote	The character to end the quote.
 * @param out		String to store the result.
 */
PJ_DECL(void) pj_scan_get_quote( pj_scanner *scanner,
				 int begin_quote, int end_quote, 
				 pj_str_t *out);

/** 
 * Get characters between quotes. If current input doesn't match begin_quote,
 * syntax error will be thrown. Note that the resulting string will contain
 * the enclosing quote.
 *
 * @param scanner	The scanner.
 * @param begin_quotes  The character array to begin the quotes. For example,
 *                      the two characters " and '.
 * @param end_quotes    The character array to end the quotes. The position
 *                      found in the begin_quotes array will be used to match
 *                      the end quotes. So if the begin_quotes was the array
 *                      of "'< the end_quotes should be "'>. If begin_array
 *                      matched the ' then the end_quotes will look for ' to
 *                      match at the end.
 * @param qsize         The size of the begin_quotes and end_quotes arrays.
 * @param out           String to store the result.
 */
PJ_DECL(void) pj_scan_get_quotes(pj_scanner *scanner,
                                 const char *begin_quotes,
                                 const char *end_quotes, int qsize,
                                 pj_str_t *out);


/**
 * Get N characters from the scanner.
 *
 * @param scanner   The scanner.
 * @param N	    Number of characters to get.
 * @param out	    String to store the result.
 */
PJ_DECL(void) pj_scan_get_n( pj_scanner *scanner,
			     unsigned N, pj_str_t *out);


/** 
 * Get one character from the scanner.
 *
 * @param scanner   The scanner.
 *
 * @return The character.
 */
PJ_DECL(int) pj_scan_get_char( pj_scanner *scanner );


/** 
 * Get characters from the scanner and move the scanner position until the
 * current character matches the spec.
 *
 * @param scanner   The scanner.
 * @param spec	    Get until the input match this spec.
 * @param out	    String to store the result.
 */
PJ_DECL(void) pj_scan_get_until( pj_scanner *scanner,
				 const pj_cis_t *spec, pj_str_t *out);


/** 
 * Get characters from the scanner and move the scanner position until the
 * current character matches until_char.
 *
 * @param scanner	The scanner.
 * @param until_char    Get until the input match this character.
 * @param out		String to store the result.
 */
PJ_DECL(void) pj_scan_get_until_ch( pj_scanner *scanner, 
				    int until_char, pj_str_t *out);


/** 
 * Get characters from the scanner and move the scanner position until the
 * current character matches until_char.
 *
 * @param scanner	The scanner.
 * @param until_spec	Get until the input match any of these characters.
 * @param out		String to store the result.
 */
PJ_DECL(void) pj_scan_get_until_chr( pj_scanner *scanner,
				     const char *until_spec, pj_str_t *out);

/** 
 * Advance the scanner N characters, and skip whitespace
 * if necessary.
 *
 * @param scanner   The scanner.
 * @param N	    Number of characters to skip.
 * @param skip	    Flag to specify whether whitespace should be skipped
 *		    after skipping the characters.
 */
PJ_DECL(void) pj_scan_advance_n( pj_scanner *scanner,
				 unsigned N, pj_bool_t skip);


/** 
 * Compare string in current position with the specified string.
 * 
 * @param scanner   The scanner.
 * @param s	    The string to compare with.
 * @param len	    Length of the string to compare.
 *
 * @return zero, <0, or >0 (just like strcmp()).
 */
PJ_DECL(int) pj_scan_strcmp( pj_scanner *scanner, const char *s, int len);


/** 
 * Case-less string comparison of current position with the specified
 * string.
 *
 * @param scanner   The scanner.
 * @param s	    The string to compare with.
 * @param len	    Length of the string to compare with.
 *
 * @return zero, <0, or >0 (just like strcmp()).
 */
PJ_DECL(int) pj_scan_stricmp( pj_scanner *scanner, const char *s, int len);

/**
 * Perform case insensitive string comparison of string in current position,
 * knowing that the string to compare only consists of alphanumeric
 * characters.
 *
 * Note that unlike #pj_scan_stricmp, this function can only return zero or
 * -1.
 *
 * @param scanner   The scanner.
 * @param s	    The string to compare with.
 * @param len	    Length of the string to compare with.
 *
 * @return	    zero if equal or -1.
 *
 * @see strnicmp_alnum, pj_stricmp_alnum
 */
PJ_DECL(int) pj_scan_stricmp_alnum( pj_scanner *scanner, const char *s, 
				    int len);


/** 
 * Get a newline from the scanner. A newline is defined as '\\n', or '\\r', or
 * "\\r\\n". If current input is not newline, syntax error will be thrown.
 *
 * @param scanner   The scanner.
 */
PJ_DECL(void) pj_scan_get_newline( pj_scanner *scanner );


/** 
 * Manually skip whitespaces according to flag that was specified when
 * the scanner was initialized.
 *
 * @param scanner   The scanner.
 */
PJ_DECL(void) pj_scan_skip_whitespace( pj_scanner *scanner );


/**
 * Skip current line.
 *
 * @param scanner   The scanner.
 */
PJ_DECL(void) pj_scan_skip_line( pj_scanner *scanner );

/** 
 * Save the full scanner state.
 *
 * @param scanner   The scanner.
 * @param state	    Variable to store scanner's state.
 */
PJ_DECL(void) pj_scan_save_state( const pj_scanner *scanner, 
				  pj_scan_state *state);


/** 
 * Restore the full scanner state.
 * Note that this would not restore the string if application has modified
 * it. This will only restore the scanner scanning position.
 *
 * @param scanner   The scanner.
 * @param state	    State of the scanner.
 */
PJ_DECL(void) pj_scan_restore_state( pj_scanner *scanner, 
				     pj_scan_state *state);

/**
 * Get current column position.
 *
 * @param scanner   The scanner.
 *
 * @return	    The column position.
 */
PJ_INLINE(int) pj_scan_get_col( const pj_scanner *scanner )
{
    return (int)(scanner->curptr - scanner->start_line);
}

/**
 * @}
 */


PJ_END_DECL

#endif