libgfortran/intrinsics/string_intrinsics_inc.c

   1 /* String intrinsics helper functions.
   2    Copyright (C) 2002-2018 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 /* Rename the functions.  */
  27 #define concat_string SUFFIX(concat_string)
  28 #define string_len_trim SUFFIX(string_len_trim)
  29 #define adjustl SUFFIX(adjustl)
  30 #define adjustr SUFFIX(adjustr)
  31 #define string_index SUFFIX(string_index)
  32 #define string_scan SUFFIX(string_scan)
  33 #define string_verify SUFFIX(string_verify)
  34 #define string_trim SUFFIX(string_trim)
  35 #define string_minmax SUFFIX(string_minmax)
  36 #define zero_length_string SUFFIX(zero_length_string)
  37 #define compare_string SUFFIX(compare_string)
  38
  39
  40 /* The prototypes.  */
  41
  42 extern void concat_string (gfc_charlen_type, CHARTYPE *,
  43                            gfc_charlen_type, const CHARTYPE *,
  44                            gfc_charlen_type, const CHARTYPE *);
  45 export_proto(concat_string);
  46
  47 extern void adjustl (CHARTYPE *, gfc_charlen_type, const CHARTYPE *);
  48 export_proto(adjustl);
  49
  50 extern void adjustr (CHARTYPE *, gfc_charlen_type, const CHARTYPE *);
  51 export_proto(adjustr);
  52
  53 extern gfc_charlen_type string_index (gfc_charlen_type, const CHARTYPE *,
  54                                       gfc_charlen_type, const CHARTYPE *,
  55                                       GFC_LOGICAL_4);
  56 export_proto(string_index);
  57
  58 extern gfc_charlen_type string_scan (gfc_charlen_type, const CHARTYPE *,
  59                                      gfc_charlen_type, const CHARTYPE *,
  60                                      GFC_LOGICAL_4);
  61 export_proto(string_scan);
  62
  63 extern gfc_charlen_type string_verify (gfc_charlen_type, const CHARTYPE *,
  64                                        gfc_charlen_type, const CHARTYPE *,
  65                                        GFC_LOGICAL_4);
  66 export_proto(string_verify);
  67
  68 extern void string_trim (gfc_charlen_type *, CHARTYPE **, gfc_charlen_type,
  69                          const CHARTYPE *);
  70 export_proto(string_trim);
  71
  72 extern void string_minmax (gfc_charlen_type *, CHARTYPE **, int, int, ...);
  73 export_proto(string_minmax);
  74
  75
  76 /* Use for functions which can return a zero-length string.  */
  77 static CHARTYPE zero_length_string = 0;
  78
  79
  80 /* Strings of unequal length are extended with pad characters.  */
  81
  82 int
  83 compare_string (gfc_charlen_type len1, const CHARTYPE *s1,
  84                 gfc_charlen_type len2, const CHARTYPE *s2)
  85 {
  86   const UCHARTYPE *s;
  87   gfc_charlen_type len;
  88   int res;
  89
  90   res = MEMCMP (s1, s2, ((len1 < len2) ? len1 : len2));
  91   if (res != 0)
  92     return res;
  93
  94   if (len1 == len2)
  95     return 0;
  96
  97   if (len1 < len2)
  98     {
  99       len = len2 - len1;
 100       s = (UCHARTYPE *) &s2[len1];
 101       res = -1;
 102     }
 103   else
 104     {
 105       len = len1 - len2;
 106       s = (UCHARTYPE *) &s1[len2];
 107       res = 1;
 108     }
 109
 110   while (len--)
 111     {
 112       if (*s != ' ')
 113         {
 114           if (*s > ' ')
 115             return res;
 116           else
 117             return -res;
 118         }
 119       s++;
 120     }
 121
 122   return 0;
 123 }
 124 iexport(compare_string);
 125
 126
 127 /* The destination and source should not overlap.  */
 128
 129 void
 130 concat_string (gfc_charlen_type destlen, CHARTYPE * dest,
 131                gfc_charlen_type len1, const CHARTYPE * s1,
 132                gfc_charlen_type len2, const CHARTYPE * s2)
 133 {
 134   if (len1 >= destlen)
 135     {
 136       memcpy (dest, s1, destlen * sizeof (CHARTYPE));
 137       return;
 138     }
 139   memcpy (dest, s1, len1 * sizeof (CHARTYPE));
 140   dest += len1;
 141   destlen -= len1;
 142
 143   if (len2 >= destlen)
 144     {
 145       memcpy (dest, s2, destlen * sizeof (CHARTYPE));
 146       return;
 147     }
 148
 149   memcpy (dest, s2, len2 * sizeof (CHARTYPE));
 150   MEMSET (&dest[len2], ' ', destlen - len2);
 151 }
 152
 153
 154 /* Return string with all trailing blanks removed.  */
 155
 156 void
 157 string_trim (gfc_charlen_type *len, CHARTYPE **dest, gfc_charlen_type slen,
 158              const CHARTYPE *src)
 159 {
 160   *len = string_len_trim (slen, src);
 161
 162   if (*len == 0)
 163     *dest = &zero_length_string;
 164   else
 165     {
 166       /* Allocate space for result string.  */
 167       *dest = xmallocarray (*len, sizeof (CHARTYPE));
 168
 169       /* Copy string if necessary.  */
 170       memcpy (*dest, src, *len * sizeof (CHARTYPE));
 171     }
 172 }
 173
 174
 175 /* The length of a string not including trailing blanks.  */
 176
 177 gfc_charlen_type
 178 string_len_trim (gfc_charlen_type len, const CHARTYPE *s)
 179 {
 180   const gfc_charlen_type long_len = (gfc_charlen_type) sizeof (unsigned long);
 181   gfc_charlen_type i;
 182
 183   i = len - 1;
 184
 185   /* If we've got the standard (KIND=1) character type, we scan the string in
 186      long word chunks to speed it up (until a long word is hit that does not
 187      consist of ' 's).  */
 188   if (sizeof (CHARTYPE) == 1 && i >= long_len)
 189     {
 190       int starting;
 191       unsigned long blank_longword;
 192
 193       /* Handle the first characters until we're aligned on a long word
 194          boundary.  Actually, s + i + 1 must be properly aligned, because
 195          s + i will be the last byte of a long word read.  */
 196       starting = ((unsigned long)
 197 #ifdef __INTPTR_TYPE__
 198                   (__INTPTR_TYPE__)
 199 #endif
 200                   (s + i + 1)) % long_len;
 201       i -= starting;
 202       for (; starting > 0; --starting)
 203         if (s[i + starting] != ' ')
 204           return i + starting + 1;
 205
 206       /* Handle the others in a batch until first non-blank long word is
 207          found.  Here again, s + i is the last byte of the current chunk,
 208          to it starts at s + i - sizeof (long) + 1.  */
 209
 210 #if __SIZEOF_LONG__ == 4
 211       blank_longword = 0x20202020L;
 212 #elif __SIZEOF_LONG__ == 8
 213       blank_longword = 0x2020202020202020L;
 214 #else
 215       #error Invalid size of long!
 216 #endif
 217
 218       while (i >= long_len)
 219         {
 220           i -= long_len;
 221           if (*((unsigned long*) (s + i + 1)) != blank_longword)
 222             {
 223               i += long_len;
 224               break;
 225             }
 226         }
 227
 228       /* Now continue for the last characters with naive approach below.  */
 229       assert (i >= 0);
 230     }
 231
 232   /* Simply look for the first non-blank character.  */
 233   while (i >= 0 && s[i] == ' ')
 234     --i;
 235   return i + 1;
 236 }
 237
 238
 239 /* Find a substring within a string.  */
 240
 241 gfc_charlen_type
 242 string_index (gfc_charlen_type slen, const CHARTYPE *str,
 243               gfc_charlen_type sslen, const CHARTYPE *sstr,
 244               GFC_LOGICAL_4 back)
 245 {
 246   gfc_charlen_type start, last, delta, i;
 247
 248   if (sslen == 0)
 249     return back ? (slen + 1) : 1;
 250
 251   if (sslen > slen)
 252     return 0;
 253
 254   if (!back)
 255     {
 256       last = slen + 1 - sslen;
 257       start = 0;
 258       delta = 1;
 259     }
 260   else
 261     {
 262       last = -1;
 263       start = slen - sslen;
 264       delta = -1;
 265     }
 266
 267   for (; start != last; start+= delta)
 268     {
 269       for (i = 0; i < sslen; i++)
 270         {
 271           if (str[start + i] != sstr[i])
 272             break;
 273         }
 274       if (i == sslen)
 275         return (start + 1);
 276     }
 277   return 0;
 278 }
 279
 280
 281 /* Remove leading blanks from a string, padding at end.  The src and dest
 282    should not overlap.  */
 283
 284 void
 285 adjustl (CHARTYPE *dest, gfc_charlen_type len, const CHARTYPE *src)
 286 {
 287   gfc_charlen_type i;
 288
 289   i = 0;
 290   while (i < len && src[i] == ' ')
 291     i++;
 292
 293   if (i < len)
 294     memcpy (dest, &src[i], (len - i) * sizeof (CHARTYPE));
 295   if (i > 0)
 296     MEMSET (&dest[len - i], ' ', i);
 297 }
 298
 299
 300 /* Remove trailing blanks from a string.  */
 301
 302 void
 303 adjustr (CHARTYPE *dest, gfc_charlen_type len, const CHARTYPE *src)
 304 {
 305   gfc_charlen_type i;
 306
 307   i = len;
 308   while (i > 0 && src[i - 1] == ' ')
 309     i--;
 310
 311   if (i < len)
 312     MEMSET (dest, ' ', len - i);
 313   memcpy (&dest[len - i], src, i * sizeof (CHARTYPE));
 314 }
 315
 316
 317 /* Scan a string for any one of the characters in a set of characters.  */
 318
 319 gfc_charlen_type
 320 string_scan (gfc_charlen_type slen, const CHARTYPE *str,
 321              gfc_charlen_type setlen, const CHARTYPE *set, GFC_LOGICAL_4 back)
 322 {
 323   gfc_charlen_type i, j;
 324
 325   if (slen == 0 || setlen == 0)
 326     return 0;
 327
 328   if (back)
 329     {
 330       for (i = slen - 1; i >= 0; i--)
 331         {
 332           for (j = 0; j < setlen; j++)
 333             {
 334               if (str[i] == set[j])
 335                 return (i + 1);
 336             }
 337         }
 338     }
 339   else
 340     {
 341       for (i = 0; i < slen; i++)
 342         {
 343           for (j = 0; j < setlen; j++)
 344             {
 345               if (str[i] == set[j])
 346                 return (i + 1);
 347             }
 348         }
 349     }
 350
 351   return 0;
 352 }
 353
 354
 355 /* Verify that a set of characters contains all the characters in a
 356    string by identifying the position of the first character in a
 357    characters that does not appear in a given set of characters.  */
 358
 359 gfc_charlen_type
 360 string_verify (gfc_charlen_type slen, const CHARTYPE *str,
 361                gfc_charlen_type setlen, const CHARTYPE *set,
 362                GFC_LOGICAL_4 back)
 363 {
 364   gfc_charlen_type start, last, delta, i;
 365
 366   if (slen == 0)
 367     return 0;
 368
 369   if (back)
 370     {
 371       last = -1;
 372       start = slen - 1;
 373       delta = -1;
 374     }
 375   else
 376     {
 377       last = slen;
 378       start = 0;
 379       delta = 1;
 380     }
 381   for (; start != last; start += delta)
 382     {
 383       for (i = 0; i < setlen; i++)
 384         {
 385           if (str[start] == set[i])
 386             break;
 387         }
 388       if (i == setlen)
 389         return (start + 1);
 390     }
 391
 392   return 0;
 393 }
 394
 395
 396 /* MIN and MAX intrinsics for strings.  The front-end makes sure that
 397    nargs is at least 2.  */
 398
 399 void
 400 string_minmax (gfc_charlen_type *rlen, CHARTYPE **dest, int op, int nargs, ...)
 401 {
 402   va_list ap;
 403   int i;
 404   CHARTYPE *next, *res;
 405   gfc_charlen_type nextlen, reslen;
 406
 407   va_start (ap, nargs);
 408   reslen = va_arg (ap, gfc_charlen_type);
 409   res = va_arg (ap, CHARTYPE *);
 410   *rlen = reslen;
 411
 412   if (res == NULL)
 413     runtime_error ("First argument of '%s' intrinsic should be present",
 414                    op > 0 ? "MAX" : "MIN");
 415
 416   for (i = 1; i < nargs; i++)
 417     {
 418       nextlen = va_arg (ap, gfc_charlen_type);
 419       next = va_arg (ap, CHARTYPE *);
 420
 421       if (next == NULL)
 422         {
 423           if (i == 1)
 424             runtime_error ("Second argument of '%s' intrinsic should be "
 425                            "present", op > 0 ? "MAX" : "MIN");
 426           else
 427             continue;
 428         }
 429
 430       if (nextlen > *rlen)
 431         *rlen = nextlen;
 432
 433       if (op * compare_string (reslen, res, nextlen, next) < 0)
 434         {
 435           reslen = nextlen;
 436           res = next;
 437         }
 438     }
 439   va_end (ap);
 440
 441   if (*rlen == 0)
 442     *dest = &zero_length_string;
 443   else
 444     {
 445       CHARTYPE *tmp = xmallocarray (*rlen, sizeof (CHARTYPE));
 446       memcpy (tmp, res, reslen * sizeof (CHARTYPE));
 447       MEMSET (&tmp[reslen], ' ', *rlen - reslen);
 448       *dest = tmp;
 449     }
 450 }