1/* Keeping a unique copy of strings.
2
3   Copyright (C) 2002-2003, 2008-2012 Free Software Foundation, Inc.
4
5   This file is part of Bison, the GNU Compiler Compiler.
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 UNIQSTR_H_
21# define UNIQSTR_H_
22
23/*-----------------------------------------.
24| Pointers to unique copies of C strings.  |
25`-----------------------------------------*/
26
27typedef char const *uniqstr;
28
29/* Return the uniqstr for STR.  */
30uniqstr uniqstr_new (char const *str);
31
32/* Return a uniqstr built by vsprintf.  In order to simply concatenate
33   strings, use UNIQSTR_CONCAT, which is a convenient wrapper around
34   this function.  */
35uniqstr uniqstr_vsprintf (char const *format, ...)
36  __attribute__ ((__format__ (__printf__, 1, 2)));
37
38/* Two uniqstr values have the same value iff they are the same.  */
39#define UNIQSTR_EQ(USTR1, USTR2) (!!((USTR1) == (USTR2)))
40
41/* Compare two uniqstr a la strcmp: negative for <, nul for =, and
42   positive for >.  Undefined order, relies on addresses.  */
43#define UNIQSTR_CMP(USTR1, USTR2) ((USTR1) - (USTR2))
44
45/*--------------------------------------.
46| Initializing, destroying, debugging.  |
47`--------------------------------------*/
48
49/* Create the string table.  */
50void uniqstrs_new (void);
51
52/* Die if STR is not a uniqstr.  */
53void uniqstr_assert (char const *str);
54
55/* Free all the memory allocated for symbols.  */
56void uniqstrs_free (void);
57
58/* Report them all.  */
59void uniqstrs_print (void);
60
61/*----------------.
62| Concatenation.  |
63`----------------*/
64
65/* Concatenate at most 20 strings and return a uniqstr.  The goal of
66   this macro is to make the caller's code a little more succinct
67   without a trivial uniqstr_vsprintf format string to maintain
68   (for example, "%s%s%s") while still benefitting from gcc's type
69   checking.  Unfortunately, because of the missing format string in the
70   macro invocation, the argument number reported by gcc for a bad
71   argument type is 1 too large.  */
72#define UNIQSTR_CONCAT(...)                                            \
73  uniqstr_vsprintf (UNIQSTR_GEN_FORMAT (__VA_ARGS__,                   \
74                                        "%s", "%s", "%s", "%s", "%s",  \
75                                        "%s", "%s", "%s", "%s", "%s",  \
76                                        "%s", "%s", "%s", "%s", "%s",  \
77                                        "%s", "%s", "%s", "%s", "%s"), \
78                    __VA_ARGS__)
79
80#define UNIQSTR_GEN_FORMAT(F1,  F2,  F3,  F4,  F5,  \
81                           F6,  F7,  F8,  F9,  F10, \
82                           F11, F12, F13, F14, F15, \
83                           F16, F17, F18, F19, F20, \
84                           ...)                     \
85  UNIQSTR_GEN_FORMAT_ (__VA_ARGS__,                 \
86                       "", "", "", "", "",          \
87                       "", "", "", "", "",          \
88                       "", "", "", "", "",          \
89                       "", "", "", "", "")
90
91#define UNIQSTR_GEN_FORMAT_(F1,  F2,  F3,  F4,  F5,       \
92                            F6,  F7,  F8,  F9,  F10,      \
93                            F11, F12, F13, F14, F15,      \
94                            F16, F17, F18, F19, F20, ...) \
95  F1  F2  F3  F4  F5  F6  F7  F8  F9  F10                 \
96  F11 F12 F13 F14 F15 F16 F17 F18 F19 F20
97
98#endif /* ! defined UNIQSTR_H_ */
99