gdb/cli/cli-utils.h

   1 /* CLI utilities.
   2
   3    Copyright (C) 2011-2017 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #ifndef CLI_UTILS_H
  21 #define CLI_UTILS_H
  22
  23 /* *PP is a string denoting a number.  Get the number.  Advance *PP
  24    after the string and any trailing whitespace.
  25
  26    The string can either be a number, or "$" followed by the name of a
  27    convenience variable, or ("$" or "$$") followed by digits.
  28
  29    TRAILER is a character which can be found after the number; most
  30    commonly this is `-'.  If you don't want a trailer, use \0.  */
  31
  32 extern int get_number_trailer (const char **pp, int trailer);
  33
  34 /* Convenience.  Like get_number_trailer, but with no TRAILER.  */
  35
  36 extern int get_number_const (const char **);
  37
  38 /* Like get_number_const, but takes a non-const "char **".  */
  39
  40 extern int get_number (char **);
  41
  42 /* Parse a number or a range.
  43    A number will be of the form handled by get_number.
  44    A range will be of the form <number1> - <number2>, and
  45    will represent all the integers between number1 and number2,
  46    inclusive.  */
  47
  48 class number_or_range_parser
  49 {
  50 public:
  51   /* Default construction.  Must call init before calling
  52      get_next.  */
  53   number_or_range_parser () {}
  54
  55   /* Calls init automatically.  */
  56   number_or_range_parser (const char *string);
  57
  58   /* STRING is the string to be parsed.  */
  59   void init (const char *string);
  60
  61   /* While processing a range, this fuction is called iteratively; At
  62      each call it will return the next value in the range.
  63
  64      At the beginning of parsing a range, the char pointer
  65      STATE->m_cur_tok will be advanced past <number1> and left
  66      pointing at the '-' token.  Subsequent calls will not advance the
  67      pointer until the range is completed.  The call that completes
  68      the range will advance the pointer past <number2>.  */
  69   int get_number ();
  70
  71   /* Setup internal state such that get_next() returns numbers in the
  72      START_VALUE to END_VALUE range.  END_PTR is where the string is
  73      advanced to when get_next() returns END_VALUE.  */
  74   void setup_range (int start_value, int end_value,
  75                     const char *end_ptr);
  76
  77   /* Returns true if parsing has completed.  */
  78   bool finished () const
  79   { return m_finished; }
  80
  81   /* Return the string being parsed.  When parsing has finished, this
  82      points past the last parsed token.  */
  83   const char *cur_tok () const
  84   { return m_cur_tok; }
  85
  86   /* True when parsing a range.  */
  87   bool in_range () const
  88   { return m_in_range; }
  89
  90   /* When parsing a range, the final value in the range.  */
  91   int end_value () const
  92   { return m_end_value; }
  93
  94   /* When parsing a range, skip past the final token in the range.  */
  95   void skip_range ()
  96   {
  97     gdb_assert (m_in_range);
  98     m_cur_tok = m_end_ptr;
  99   }
 100
 101 private:
 102   /* No need for these.  They are intentionally not defined anywhere.  */
 103   number_or_range_parser (const number_or_range_parser &);
 104   number_or_range_parser &operator= (const number_or_range_parser &);
 105
 106   /* True if parsing has completed.  */
 107   bool m_finished;
 108
 109   /* The string being parsed.  When parsing has finished, this points
 110      past the last parsed token.  */
 111   const char *m_cur_tok;
 112
 113   /* Last value returned.  */
 114   int m_last_retval;
 115
 116   /* When parsing a range, the final value in the range.  */
 117   int m_end_value;
 118
 119   /* When parsing a range, a pointer past the final token in the
 120      range.  */
 121   const char *m_end_ptr;
 122
 123   /* True when parsing a range.  */
 124   bool m_in_range;
 125 };
 126
 127 /* Accept a number and a string-form list of numbers such as is
 128    accepted by get_number_or_range.  Return TRUE if the number is
 129    in the list.
 130
 131    By definition, an empty list includes all numbers.  This is to
 132    be interpreted as typing a command such as "delete break" with
 133    no arguments.  */
 134
 135 extern int number_is_in_list (const char *list, int number);
 136
 137 /* Reverse S to the last non-whitespace character without skipping past
 138    START.  */
 139
 140 extern const char *remove_trailing_whitespace (const char *start,
 141                                                const char *s);
 142
 143 /* Same, for non-const S.  */
 144
 145 static inline char *
 146 remove_trailing_whitespace (const char *start, char *s)
 147 {
 148   return (char *) remove_trailing_whitespace (start, (const char *) s);
 149 }
 150
 151 /* A helper function to extract an argument from *ARG.  An argument is
 152    delimited by whitespace.  The return value is either NULL if no
 153    argument was found, or an xmalloc'd string.  */
 154
 155 extern char *extract_arg (char **arg);
 156
 157 /* A const-correct version of "extract_arg".
 158
 159    Since the returned value is xmalloc'd, it eventually needs to be
 160    xfree'ed, which prevents us from making it const as well.  */
 161
 162 extern char *extract_arg_const (const char **arg);
 163
 164 /* A helper function that looks for an argument at the start of a
 165    string.  The argument must also either be at the end of the string,
 166    or be followed by whitespace.  Returns 1 if it finds the argument,
 167    0 otherwise.  If the argument is found, it updates *STR.  */
 168 extern int check_for_argument (const char **str, const char *arg, int arg_len);
 169
 170 /* Same, for non-const STR.  */
 171
 172 static inline int
 173 check_for_argument (char **str, const char *arg, int arg_len)
 174 {
 175   return check_for_argument (const_cast<const char **> (str),
 176                              arg, arg_len);
 177 }
 178
 179 #endif /* CLI_UTILS_H */