libgfortran/runtime/string.c

   1 /* Copyright (C) 2002, 2003, 2005, 2007 Free Software Foundation, Inc.
   2    Contributed by Paul Brook
   3
   4 This file is part of the GNU Fortran 95 runtime library (libgfortran).
   5
   6 Libgfortran is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 In addition to the permissions in the GNU General Public License, the
  12 Free Software Foundation gives you unlimited permission to link the
  13 compiled version of this file into combinations with other programs,
  14 and to distribute those combinations without any restriction coming
  15 from the use of this file.  (The General Public License restrictions
  16 do apply in other respects; for example, they cover modification of
  17 the file, and distribution when not linked into a combine
  18 executable.)
  19
  20 Libgfortran is distributed in the hope that it will be useful,
  21 but WITHOUT ANY WARRANTY; without even the implied warranty of
  22 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  23 GNU General Public License for more details.
  24
  25 You should have received a copy of the GNU General Public License
  26 along with libgfortran; see the file COPYING.  If not, write to
  27 the Free Software Foundation, 51 Franklin Street, Fifth Floor,
  28 Boston, MA 02110-1301, USA.  */
  29
  30 #include "libgfortran.h"
  31 #include <string.h>
  32
  33 /* Compare a C-style string with a fortran style string in a case-insensitive
  34    manner.  Used for decoding string options to various statements.  Returns
  35    zero if not equal, nonzero if equal.  */
  36
  37 static int
  38 compare0 (const char *s1, gfc_charlen_type s1_len, const char *s2)
  39 {
  40   size_t len;
  41
  42   /* Strip trailing blanks from the Fortran string.  */
  43   len = fstrlen (s1, s1_len);
  44   if (len != strlen(s2)) return 0; /* don't match */
  45   return strncasecmp (s1, s2, len) == 0;
  46 }
  47
  48
  49 /* Given a fortran string, return its length exclusive of the trailing
  50    spaces.  */
  51
  52 gfc_charlen_type
  53 fstrlen (const char *string, gfc_charlen_type len)
  54 {
  55   for (; len > 0; len--)
  56     if (string[len-1] != ' ')
  57       break;
  58
  59   return len;
  60 }
  61
  62
  63 /* Copy a Fortran string (not null-terminated, hence length arguments
  64    for both source and destination strings. Returns the non-padded
  65    length of the destination.  */
  66
  67 gfc_charlen_type
  68 fstrcpy (char *dest, gfc_charlen_type destlen,
  69          const char *src, gfc_charlen_type srclen)
  70 {
  71   if (srclen >= destlen)
  72     {
  73       /* This will truncate if too long.  */
  74       memcpy (dest, src, destlen);
  75       return destlen;
  76     }
  77   else
  78     {
  79       memcpy (dest, src, srclen);
  80       /* Pad with spaces.  */
  81       memset (&dest[srclen], ' ', destlen - srclen);
  82       return srclen;
  83     }
  84 }
  85
  86
  87 /* Copy a null-terminated C string to a non-null-terminated Fortran
  88    string. Returns the non-padded length of the destination string.  */
  89
  90 gfc_charlen_type
  91 cf_strcpy (char *dest, gfc_charlen_type dest_len, const char *src)
  92 {
  93   size_t src_len;
  94
  95   src_len = strlen (src);
  96
  97   if (src_len >= (size_t) dest_len)
  98     {
  99       /* This will truncate if too long.  */
 100       memcpy (dest, src, dest_len);
 101       return dest_len;
 102     }
 103   else
 104     {
 105       memcpy (dest, src, src_len);
 106       /* Pad with spaces.  */
 107       memset (&dest[src_len], ' ', dest_len - src_len);
 108       return src_len;
 109     }
 110 }
 111
 112
 113 /* Given a fortran string and an array of st_option structures, search through
 114    the array to find a match.  If the option is not found, we generate an error
 115    if no default is provided.  */
 116
 117 int
 118 find_option (st_parameter_common *cmp, const char *s1, gfc_charlen_type s1_len,
 119              const st_option * opts, const char *error_message)
 120 {
 121   for (; opts->name; opts++)
 122     if (compare0 (s1, s1_len, opts->name))
 123       return opts->value;
 124
 125   generate_error (cmp, LIBERROR_BAD_OPTION, error_message);
 126
 127   return -1;
 128 }