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