gdb/cli/cli-utils.h

   1 /* CLI utilities.
   2
   3    Copyright (C) 2011-2019 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 char **);
  37
  38 /* Like the above, but takes a non-const "char **".  */
  39
  40 extern int get_number (char **);
  41
  42 /* Extract from ARGS the arguments [-q] [-t TYPEREGEXP] [--] NAMEREGEXP.
  43
  44    The caller is responsible to initialize *QUIET to false, *REGEXP
  45    and *T_REGEXP to "".
  46    extract_info_print_args can then be called iteratively to search
  47    for valid arguments, as part of a 'main parsing loop' searching for
  48    -q/-t/-- arguments together with other flags and options.
  49
  50    Returns true and updates *ARGS + one of *QUIET, *REGEXP, *T_REGEXP if
  51    it finds a valid argument.
  52    Returns false if no valid argument is found at the beginning of ARGS.  */
  53
  54 extern bool extract_info_print_args (const char **args,
  55                                      bool *quiet,
  56                                      std::string *regexp,
  57                                      std::string *t_regexp);
  58
  59 /* Throws an error telling the user that ARGS starts with an option
  60    unrecognized by COMMAND.  */
  61
  62 extern void report_unrecognized_option_error (const char *command,
  63                                               const char *args);
  64
  65
  66 /* Builds the help string for a command documented by PREFIX,
  67    followed by the extract_info_print_args help for ENTITY_KIND.  */
  68
  69 const char *info_print_args_help (const char *prefix,
  70                                   const char *entity_kind);
  71
  72 /* Parse a number or a range.
  73    A number will be of the form handled by get_number.
  74    A range will be of the form <number1> - <number2>, and
  75    will represent all the integers between number1 and number2,
  76    inclusive.  */
  77
  78 class number_or_range_parser
  79 {
  80 public:
  81   /* Default construction.  Must call init before calling
  82      get_next.  */
  83   number_or_range_parser () {}
  84
  85   /* Calls init automatically.  */
  86   number_or_range_parser (const char *string);
  87
  88   /* STRING is the string to be parsed.  */
  89   void init (const char *string);
  90
  91   /* While processing a range, this fuction is called iteratively; At
  92      each call it will return the next value in the range.
  93
  94      At the beginning of parsing a range, the char pointer
  95      STATE->m_cur_tok will be advanced past <number1> and left
  96      pointing at the '-' token.  Subsequent calls will not advance the
  97      pointer until the range is completed.  The call that completes
  98      the range will advance the pointer past <number2>.  */
  99   int get_number ();
 100
 101   /* Setup internal state such that get_next() returns numbers in the
 102      START_VALUE to END_VALUE range.  END_PTR is where the string is
 103      advanced to when get_next() returns END_VALUE.  */
 104   void setup_range (int start_value, int end_value,
 105                     const char *end_ptr);
 106
 107   /* Returns true if parsing has completed.  */
 108   bool finished () const;
 109
 110   /* Return the string being parsed.  When parsing has finished, this
 111      points past the last parsed token.  */
 112   const char *cur_tok () const
 113   { return m_cur_tok; }
 114
 115   /* True when parsing a range.  */
 116   bool in_range () const
 117   { return m_in_range; }
 118
 119   /* When parsing a range, the final value in the range.  */
 120   int end_value () const
 121   { return m_end_value; }
 122
 123   /* When parsing a range, skip past the final token in the range.  */
 124   void skip_range ()
 125   {
 126     gdb_assert (m_in_range);
 127     m_cur_tok = m_end_ptr;
 128     m_in_range = false;
 129   }
 130
 131 private:
 132   /* No need for these.  They are intentionally not defined anywhere.  */
 133   number_or_range_parser (const number_or_range_parser &);
 134   number_or_range_parser &operator= (const number_or_range_parser &);
 135
 136   /* The string being parsed.  When parsing has finished, this points
 137      past the last parsed token.  */
 138   const char *m_cur_tok;
 139
 140   /* Last value returned.  */
 141   int m_last_retval;
 142
 143   /* When parsing a range, the final value in the range.  */
 144   int m_end_value;
 145
 146   /* When parsing a range, a pointer past the final token in the
 147      range.  */
 148   const char *m_end_ptr;
 149
 150   /* True when parsing a range.  */
 151   bool m_in_range;
 152 };
 153
 154 /* Accept a number and a string-form list of numbers such as is
 155    accepted by get_number_or_range.  Return TRUE if the number is
 156    in the list.
 157
 158    By definition, an empty list includes all numbers.  This is to
 159    be interpreted as typing a command such as "delete break" with
 160    no arguments.  */
 161
 162 extern int number_is_in_list (const char *list, int number);
 163
 164 /* Reverse S to the last non-whitespace character without skipping past
 165    START.  */
 166
 167 extern const char *remove_trailing_whitespace (const char *start,
 168                                                const char *s);
 169
 170 /* Same, for non-const S.  */
 171
 172 static inline char *
 173 remove_trailing_whitespace (const char *start, char *s)
 174 {
 175   return (char *) remove_trailing_whitespace (start, (const char *) s);
 176 }
 177
 178 /* A helper function to extract an argument from *ARG.  An argument is
 179    delimited by whitespace.  The return value is empty if no argument
 180    was found.  */
 181
 182 extern std::string extract_arg (char **arg);
 183
 184 /* A const-correct version of the above.  */
 185
 186 extern std::string extract_arg (const char **arg);
 187
 188 /* A helper function that looks for an argument at the start of a
 189    string.  The argument must also either be at the end of the string,
 190    or be followed by whitespace.  Returns 1 if it finds the argument,
 191    0 otherwise.  If the argument is found, it updates *STR.  */
 192 extern int check_for_argument (const char **str, const char *arg, int arg_len);
 193
 194 /* Same, for non-const STR.  */
 195
 196 static inline int
 197 check_for_argument (char **str, const char *arg, int arg_len)
 198 {
 199   return check_for_argument (const_cast<const char **> (str),
 200                              arg, arg_len);
 201 }
 202
 203 /* A helper function that looks for a set of flags at the start of a
 204    string.  The possible flags are given as a null terminated string.
 205    A flag in STR must either be at the end of the string,
 206    or be followed by whitespace.
 207    Returns 0 if no valid flag is found at the start of STR.
 208    Otherwise updates *STR, and returns N (which is > 0),
 209    such that FLAGS [N - 1] is the valid found flag.  */
 210 extern int parse_flags (const char **str, const char *flags);
 211
 212 /* qcs_flags struct regroups the flags parsed by parse_flags_qcs.  */
 213
 214 struct qcs_flags
 215 {
 216   bool quiet = false;
 217   bool cont = false;
 218   bool silent = false;
 219 };
 220
 221 /* A helper function that uses parse_flags to handle the flags qcs :
 222      A flag -q sets FLAGS->QUIET to true.
 223      A flag -c sets FLAGS->CONT to true.
 224      A flag -s sets FLAGS->SILENT to true.
 225
 226    The caller is responsible to initialize *FLAGS to false before the (first)
 227    call to parse_flags_qcs.
 228    parse_flags_qcs can then be called iteratively to search for more
 229    valid flags, as part of a 'main parsing loop' searching for -q/-c/-s
 230    flags together with other flags and options.
 231
 232    Returns true and updates *STR and one of FLAGS->QUIET, FLAGS->CONT,
 233    FLAGS->SILENT if it finds a valid flag.
 234    Returns false if no valid flag is found at the beginning of STR.
 235
 236    Throws an error if a flag is found such that both FLAGS->CONT and
 237    FLAGS->SILENT are true.  */
 238
 239 extern bool parse_flags_qcs (const char *which_command, const char **str,
 240                              qcs_flags *flags);
 241 #endif /* CLI_UTILS_H */