src/libstrongswan/utils/parser_helper.h

   1 /*
   2  * Copyright (C) 2014 Tobias Brunner
   3  * Hochschule fuer Technik Rapperswil
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License as published by the
   7  * Free Software Foundation; either version 2 of the License, or (at your
   8  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  12  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  13  * for more details.
  14  */
  15
  16 /**
  17  * @defgroup parser_helper parser_helper
  18  * @{ @ingroup utils
  19  */
  20
  21 #ifndef PARSER_HELPER_H_
  22 #define PARSER_HELPER_H_
  23
  24 #include <collections/array.h>
  25 #include <bio/bio_writer.h>
  26
  27 typedef struct parser_helper_t parser_helper_t;
  28
  29 /**
  30  * Helper class for flex/bison based parsers.
  31  *
  32  * <code>PREFIX</code> equals whatever is configure with
  33  * <code>%option prefix</code> resp. <code>%name-prefix</code>.
  34  */
  35 struct parser_helper_t {
  36
  37         /**
  38          * A user defined parser context object.
  39          */
  40         const void *context;
  41
  42         /**
  43          * Opaque object allocated by the lexer, should be set with:
  44          * @code
  45          * PREFIXlex_init_extra(helper, &helper->scanner).
  46          * @endcode
  47          */
  48         void *scanner;
  49
  50         /**
  51          * Function to determine the current line number (defined by the lexer).
  52          *
  53          * Basically, this should be assigned to <code>PREFIXget_lineno</code>.
  54          *
  55          * @param scanner       the lexer
  56          * @return                      current line number
  57          */
  58         int (*get_lineno)(void *scanner);
  59
  60         /**
  61          * Resolves the given include pattern, relative to the location of the
  62          * current file.
  63          *
  64          * Call file_next() to open the next file.
  65          *
  66          * @param pattern       file pattern
  67          */
  68         void (*file_include)(parser_helper_t *this, char *pattern);
  69
  70         /**
  71          * Get the next file to process.
  72          *
  73          * This will return NULL if all files matching the most recent pattern
  74          * have been handled. If there are other patterns the next call will then
  75          * return the next file matching the previous pattern.
  76          *
  77          * When hitting <code>\<\<EOF\>\></code> first call
  78          * @code
  79          * PREFIXpop_buffer_state(yyscanner);
  80          * @endcode
  81          * then call this method to check if there are more files to include for
  82          * the most recent call to file_include(), if so, call
  83          * @code
  84          * PREFIXset_in(file, helper->scanner);
  85          * PREFIXpush_buffer_state(PREFIX_create_buffer(file, YY_BUF_SIZE,
  86          *                                              helper->scanner), helper->scanner);
  87          * @endcode
  88          *
  89          * If there are no more files to process check
  90          * <code>YY_CURRENT_BUFFER</code> and if it is FALSE call yyterminate().
  91          *
  92          * @return                      next file to process, or NULL (see comment)
  93          */
  94         FILE *(*file_next)(parser_helper_t *this);
  95
  96         /**
  97          * Start parsing a string, discards any currently stored data.
  98          */
  99         void (*string_init)(parser_helper_t *this);
 100
 101         /**
 102          * Append the given string.
 103          *
 104          * @param str           string to append
 105          */
 106         void (*string_add)(parser_helper_t *this, char *str);
 107
 108         /**
 109          * Extract the current string buffer as null-terminated string. Can only
 110          * be called once per string.
 111          *
 112          * @return                      allocated string
 113          */
 114         char *(*string_get)(parser_helper_t *this);
 115
 116         /**
 117          * Destroy this instance.
 118          */
 119         void (*destroy)(parser_helper_t *this);
 120 };
 121
 122 /**
 123  * Log the given message either as error or warning
 124  *
 125  * @param level         log level
 126  * @param ctx           current parser context
 127  * @param fmt           error message format
 128  * @param ...           additional arguments
 129  */
 130 void parser_helper_log(int level, parser_helper_t *ctx, char *fmt, ...);
 131
 132 #define PARSER_DBG1(ctx, fmt, ...) parser_helper_log(1, ctx, fmt, ##__VA_ARGS__)
 133 #define PARSER_DBG2(ctx, fmt, ...) parser_helper_log(2, ctx, fmt, ##__VA_ARGS__)
 134 #define PARSER_DBG3(ctx, fmt, ...) parser_helper_log(3, ctx, fmt, ##__VA_ARGS__)
 135
 136 /**
 137  * Create a parser helper object
 138  *
 139  * @param context               user defined parser context
 140  * @return                              parser helper
 141  */
 142 parser_helper_t *parser_helper_create(void *context);
 143
 144 #endif /** PARSER_HELPER_H_ @}*/