src/uniqstr.h

   1 /* Keeping a unique copy of strings.
   2
   3    Copyright (C) 2002-2003, 2008-2011 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
  27 typedef char const *uniqstr;
  28
  29 /* Return the uniqstr for STR.  */
  30 uniqstr 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.  */
  35 uniqstr 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.  */
  50 void uniqstrs_new (void);
  51
  52 /* Die if STR is not a uniqstr.  */
  53 void uniqstr_assert (char const *str);
  54
  55 /* Free all the memory allocated for symbols.  */
  56 void uniqstrs_free (void);
  57
  58 /* Report them all.  */
  59 void 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_ */