| /* $Id$ |
| * |
| */ |
| |
| #ifndef __PJ_PARSER_H__ |
| #define __PJ_PARSER_H__ |
| |
| /** |
| * @file scanner.h |
| * @brief Text Scanning. |
| */ |
| |
| #include <pj/types.h> |
| |
| PJ_BEGIN_DECL |
| |
| /** |
| * @defgroup PJ_SCAN Text Scanning |
| * @ingroup PJ_MISC |
| * @brief |
| * Text scanning utility. |
| */ |
| |
| /** |
| * @defgroup PJ_CHARSPEC Character Filter Specification |
| * @ingroup PJ_SCAN |
| * @brief |
| * The type pj_char_spec is a specification of character set used in |
| * scanner. Application can define multiple character specs, such as to |
| * scan alpha numerics, numbers, tokens, etc. |
| * @{ |
| */ |
| |
| /** |
| * This describes the type of individual character specification in |
| * #pj_char_spec. |
| */ |
| typedef pj_uint8_t pj_char_spec_element_t; |
| |
| /** |
| * The character specification is implemented as array of boolean flags. Each |
| * flag indicates the membership of the character in the spec. If the flag |
| * at one position is non-zero, then the character at that position belongs |
| * to the specification, and vice versa. |
| */ |
| typedef pj_char_spec_element_t pj_char_spec[256]; |
| // Note: it's got to be 256 (not 128) to cater for extended character in input. |
| |
| /** |
| * Initialize character spec. |
| * @param cs the scanner character specification. |
| */ |
| PJ_DECL(void) pj_cs_init( pj_char_spec cs); |
| |
| /** |
| * Set the membership of the specified character to TRUE. |
| * @param cs the scanner character specification. |
| * @param c the character. |
| */ |
| PJ_DECL(void) pj_cs_set( pj_char_spec cs, int c); |
| |
| /** |
| * Add the characters in the specified range '[cstart, cend)' to the |
| * specification (the last character itself ('cend') is not added). |
| * @param cs the scanner character specification. |
| * @param cstart the first character in the range. |
| * @param cend the next character after the last character in the range. |
| */ |
| PJ_DECL(void) pj_cs_add_range( pj_char_spec cs, int cstart, int cend); |
| |
| /** |
| * Add alphabetic characters to the specification. |
| * @param cs the scanner character specification. |
| */ |
| PJ_DECL(void) pj_cs_add_alpha( pj_char_spec cs); |
| |
| /** |
| * Add numeric characters to the specification. |
| * @param cs the scanner character specification. |
| */ |
| PJ_DECL(void) pj_cs_add_num( pj_char_spec cs); |
| |
| /** |
| * Add the characters in the string to the specification. |
| * @param cs the scanner character specification. |
| * @param str the string. |
| */ |
| PJ_DECL(void) pj_cs_add_str( pj_char_spec cs, const char *str); |
| |
| /** |
| * Delete characters in the specified range from the specification. |
| * @param cs the scanner character specification. |
| * @param cstart the first character in the range. |
| * @param cend the next character after the last character in the range. |
| */ |
| PJ_DECL(void) pj_cs_del_range( pj_char_spec cs, int cstart, int cend); |
| |
| /** |
| * Delete characters in the specified string from the specification. |
| * @param cs the scanner character specification. |
| * @param str the string. |
| */ |
| PJ_DECL(void) pj_cs_del_str( pj_char_spec cs, const char *str); |
| |
| /** |
| * Invert specification. |
| * @param cs the scanner character specification. |
| */ |
| PJ_DECL(void) pj_cs_invert( pj_char_spec cs ); |
| |
| /** |
| * Check whether the specified character belongs to the specification. |
| * @param cs the scanner character specification. |
| * @param c the character to check for matching. |
| */ |
| PJ_INLINE(int) pj_cs_match( const pj_char_spec cs, int c ) |
| { |
| return cs[c]; |
| } |
| |
| /** |
| * @} |
| */ |
| |
| /** |
| * @defgroup PJ_SCANNER Text Scanner |
| * @ingroup PJ_SCAN |
| * @{ |
| */ |
| |
| /** |
| * Flags for scanner. |
| */ |
| enum |
| { |
| /** This flags specifies that the scanner should automatically skip |
| whitespaces |
| */ |
| PJ_SCAN_AUTOSKIP_WS = 1, |
| |
| /** This flags specifies that the scanner should automatically skip |
| SIP header continuation. This flag implies PJ_SCAN_AUTOSKIP_WS. |
| */ |
| PJ_SCAN_AUTOSKIP_WS_HEADER = 3, |
| |
| /** Auto-skip new lines. |
| */ |
| PJ_SCAN_AUTOSKIP_NEWLINE = 4, |
| }; |
| |
| |
| /* Forward decl. */ |
| struct pj_scanner; |
| |
| |
| /** |
| * The callback function type to be called by the scanner when it encounters |
| * syntax error. |
| * @param scanner The scanner instance that calls the callback . |
| */ |
| typedef void (*pj_syn_err_func_ptr)(struct pj_scanner *scanner); |
| |
| |
| /** |
| * The text scanner structure. |
| */ |
| typedef struct pj_scanner |
| { |
| char *begin; /**< Start of input buffer. */ |
| char *end; /**< End of input buffer. */ |
| char *curptr; /**< Current pointer. */ |
| int line; /**< Current line. */ |
| int col; /**< Current column. */ |
| int skip_ws; /**< Skip whitespace flag. */ |
| pj_syn_err_func_ptr callback; /**< Syntax error callback. */ |
| } pj_scanner; |
| |
| |
| /** |
| * This structure can be used by application to store the state of the parser, |
| * so that the scanner state can be rollback to this state when necessary. |
| */ |
| typedef struct pj_scan_state |
| { |
| char *curptr; /**< Current scanner's pointer. */ |
| int line; /**< Current line. */ |
| int col; /**< Current column. */ |
| } pj_scan_state; |
| |
| |
| /** |
| * Initialize the scanner. Note that the input string buffer must have |
| * length at least buflen+1 because the scanner will NULL terminate the |
| * string during initialization. |
| * |
| * @param scanner The scanner to be initialized. |
| * @param bufstart The input buffer to scan. Note that buffer[buflen] will be |
| * filled with NULL char until scanner is destroyed, so |
| * the actual buffer length must be at least buflen+1. |
| * @param buflen The length of the input buffer, which normally is |
| * strlen(bufstart). |
| * @param options Zero, or combination of PJ_SCAN_AUTOSKIP_WS or |
| * PJ_SCAN_AUTOSKIP_WS_HEADER |
| * @param callback Callback to be called when the scanner encounters syntax |
| * error condition. |
| */ |
| PJ_DECL(void) pj_scan_init( pj_scanner *scanner, char *bufstart, int buflen, |
| unsigned options, |
| pj_syn_err_func_ptr callback ); |
| |
| |
| /** |
| * Call this function when application has finished using the scanner. |
| * |
| * @param scanner The scanner. |
| */ |
| PJ_DECL(void) pj_scan_fini( pj_scanner *scanner ); |
| |
| |
| /** |
| * Determine whether the EOF condition for the scanner has been met. |
| * |
| * @param scanner The scanner. |
| * |
| * @return Non-zero if scanner is EOF. |
| */ |
| PJ_INLINE(int) pj_scan_is_eof( const pj_scanner *scanner) |
| { |
| return scanner->curptr >= scanner->end; |
| } |
| |
| |
| /** |
| * Peek strings in current position according to parameter spec, 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 thrown. |
| * |
| * @param scanner The scanner. |
| * @param spec The spec to match input string. |
| * @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( pj_scanner *scanner, |
| const pj_char_spec spec, pj_str_t *out); |
| |
| |
| /** |
| * Peek len characters in current position, and return them in out parameter. |
| * Note that whitespaces or newlines will be returned as it is, regardless |
| * 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_char_spec 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_char_spec spec, pj_str_t *out); |
| |
| |
| /** |
| * Get characters between quotes. If current input doesn't match begin_quote, |
| * syntax error will be thrown. |
| * |
| * @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 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 (unknown) |
| */ |
| PJ_DECL(int) pj_scan_get_char( pj_scanner *scanner ); |
| |
| |
| /** |
| * 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 ); |
| |
| |
| /** |
| * 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_char_spec 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); |
| |
| |
| /** |
| * 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 ); |
| |
| |
| /** |
| * Save the full scanner state. |
| * |
| * @param scanner The scanner. |
| * @param state Variable to store scanner's state. |
| */ |
| PJ_DECL(void) pj_scan_save_state( 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); |
| |
| /** |
| * @} |
| */ |
| |
| #if PJ_FUNCTIONS_ARE_INLINED |
| # include "scanner_i.h" |
| #endif |
| |
| |
| PJ_END_DECL |
| |
| #endif |
| |