diff options
Diffstat (limited to 'pjlib/include/pj/scanner.h')
| -rw-r--r-- | pjlib/include/pj/scanner.h | 454 |
1 files changed, 454 insertions, 0 deletions
diff --git a/pjlib/include/pj/scanner.h b/pjlib/include/pj/scanner.h new file mode 100644 index 00000000..5b04c687 --- /dev/null +++ b/pjlib/include/pj/scanner.h @@ -0,0 +1,454 @@ +/* $Header: /pjproject-0.3/pjlib/include/pj/scanner.h 10 10/14/05 12:26a Bennylp $ */
+
+#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
+
|