cli-utils.h revision 1.7 
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
32extern int get_number_trailer (const char **pp, int trailer);
33
34/* Convenience.  Like get_number_trailer, but with no TRAILER.  */
35
36extern int get_number_const (const char **);
37
38/* Like get_number_const, but takes a non-const "char **".  */
39
40extern 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
48class number_or_range_parser
49{
50public:
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
101private:
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
135extern 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
140extern const char *remove_trailing_whitespace (const char *start,
141					       const char *s);
142
143/* Same, for non-const S.  */
144
145static inline char *
146remove_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
155extern 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
162extern 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.  */
168extern int check_for_argument (const char **str, const char *arg, int arg_len);
169
170/* Same, for non-const STR.  */
171
172static inline int
173check_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 */
180