libgfortran/intrinsics/string_intrinsics.c

   1 /* String intrinsics helper functions.
   2    Copyright (C) 2008-2023 Free Software Foundation, Inc.
   3
   4 This file is part of the GNU Fortran runtime library (libgfortran).
   5
   6 Libgfortran is free software; you can redistribute it and/or
   7 modify it under the terms of the GNU General Public
   8 License as published by the Free Software Foundation; either
   9 version 3 of the License, or (at your option) any later version.
  10
  11 Libgfortran is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 Under Section 7 of GPL version 3, you are granted additional
  17 permissions described in the GCC Runtime Library Exception, version
  18 3.1, as published by the Free Software Foundation.
  19
  20 You should have received a copy of the GNU General Public License and
  21 a copy of the GCC Runtime Library Exception along with this program;
  22 see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  23 <http://www.gnu.org/licenses/>.  */
  24
  25
  26 /* Unlike what the name of this file suggests, we don't actually
  27    implement the Fortran intrinsics here.  At least, not with the
  28    names they have in the standard.  The functions here provide all
  29    the support we need for the standard string intrinsics, and the
  30    compiler translates the actual intrinsics calls to calls to
  31    functions in this file.  */
  32
  33 #include "libgfortran.h"
  34
  35 #include <string.h>
  36 #include <assert.h>
  37
  38
  39 /* Helper function to set parts of wide strings to a constant (usually
  40    spaces).  */
  41
  42 static gfc_char4_t *
  43 memset_char4 (gfc_char4_t *b, gfc_char4_t c, size_t len)
  44 {
  45   size_t i;
  46
  47   for (i = 0; i < len; i++)
  48     b[i] = c;
  49
  50   return b;
  51 }
  52
  53 /* Compare wide character types, which are handled internally as
  54    unsigned 4-byte integers.  */
  55 int
  56 memcmp_char4 (const void *a, const void *b, size_t len)
  57 {
  58   const GFC_UINTEGER_4 *pa = a;
  59   const GFC_UINTEGER_4 *pb = b;
  60   while (len-- > 0)
  61     {
  62       if (*pa != *pb)
  63         return *pa < *pb ? -1 : 1;
  64       pa ++;
  65       pb ++;
  66     }
  67   return 0;
  68 }
  69
  70
  71 /* All other functions are defined using a few generic macros in
  72    string_intrinsics_inc.c, so we avoid code duplication between the
  73    various character type kinds.  */
  74
  75 #undef  CHARTYPE
  76 #define CHARTYPE char
  77 #undef  UCHARTYPE
  78 #define UCHARTYPE unsigned char
  79 #undef  SUFFIX
  80 #define SUFFIX(x) x
  81 #undef  MEMSET
  82 #define MEMSET memset
  83 #undef  MEMCMP
  84 #define MEMCMP memcmp
  85
  86 #include "string_intrinsics_inc.c"
  87
  88
  89 #undef  CHARTYPE
  90 #define CHARTYPE gfc_char4_t
  91 #undef  UCHARTYPE
  92 #define UCHARTYPE gfc_char4_t
  93 #undef  SUFFIX
  94 #define SUFFIX(x) x ## _char4
  95 #undef  MEMSET
  96 #define MEMSET memset_char4
  97 #undef  MEMCMP
  98 #define MEMCMP memcmp_char4
  99
 100 #include "string_intrinsics_inc.c"
 101