libguile/strings.c

   1 /* Copyright (C) 1995,1996,1998,2000,2001 Free Software Foundation, Inc.
   2  *
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2, or (at your option)
   6  * any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this software; see the file COPYING.  If not, write to
  15  * the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  16  * Boston, MA 02111-1307 USA
  17  *
  18  * As a special exception, the Free Software Foundation gives permission
  19  * for additional uses of the text contained in its release of GUILE.
  20  *
  21  * The exception is that, if you link the GUILE library with other files
  22  * to produce an executable, this does not by itself cause the
  23  * resulting executable to be covered by the GNU General Public License.
  24  * Your use of that executable is in no way restricted on account of
  25  * linking the GUILE library code into it.
  26  *
  27  * This exception does not however invalidate any other reasons why
  28  * the executable file might be covered by the GNU General Public License.
  29  *
  30  * This exception applies only to the code released by the
  31  * Free Software Foundation under the name GUILE.  If you copy
  32  * code from other Free Software Foundation releases into a copy of
  33  * GUILE, as the General Public License permits, the exception does
  34  * not apply to the code that you add in this way.  To avoid misleading
  35  * anyone as to the status of such modified files, you must delete
  36  * this exception notice from them.
  37  *
  38  * If you write modifications of your own for GUILE, it is your choice
  39  * whether to permit this exception to apply to your modifications.
  40  * If you do not wish that, delete this exception notice.  */
  41
  42
  43 \f
  44
  45 #include <string.h>
  46
  47 #include "libguile/_scm.h"
  48 #include "libguile/chars.h"
  49 #include "libguile/root.h"
  50 #include "libguile/strings.h"
  51 #include "libguile/deprecation.h"
  52 #include "libguile/validate.h"
  53
  54 \f
  55
  56 /* {Strings}
  57  */
  58
  59 SCM_DEFINE (scm_string_p, "string?", 1, 0, 0,
  60             (SCM obj),
  61             "Return @code{#t} iff @var{obj} is a string, else returns\n"
  62             "@code{#f}.")
  63 #define FUNC_NAME s_scm_string_p
  64 {
  65   return SCM_BOOL (SCM_STRINGP (obj));
  66 }
  67 #undef FUNC_NAME
  68
  69
  70 SCM_REGISTER_PROC (s_scm_list_to_string, "list->string", 1, 0, 0, scm_string);
  71
  72 SCM_DEFINE (scm_string, "string", 0, 0, 1,
  73             (SCM chrs),
  74             "@deffnx primitive list->string chrs\n"
  75             "Return a newly allocated string composed of the arguments,\n"
  76             "@var{chrs}.")
  77 #define FUNC_NAME s_scm_string
  78 {
  79   SCM result;
  80
  81   {
  82     long i = scm_ilength (chrs);
  83
  84     SCM_ASSERT (i >= 0, chrs, SCM_ARG1, FUNC_NAME);
  85     result = scm_allocate_string (i);
  86   }
  87
  88   {
  89     unsigned char *data = SCM_STRING_UCHARS (result);
  90
  91     while (!SCM_NULLP (chrs))
  92       {
  93         SCM elt = SCM_CAR (chrs);
  94
  95         SCM_VALIDATE_CHAR (SCM_ARGn, elt);
  96         *data++ = SCM_CHAR (elt);
  97         chrs = SCM_CDR (chrs);
  98       }
  99   }
 100   return result;
 101 }
 102 #undef FUNC_NAME
 103
 104
 105 /* converts C scm_array of strings to SCM scm_list of strings. */
 106 /* If argc < 0, a null terminated scm_array is assumed. */
 107 SCM
 108 scm_makfromstrs (int argc, char **argv)
 109 {
 110   int i = argc;
 111   SCM lst = SCM_EOL;
 112   if (0 > i)
 113     for (i = 0; argv[i]; i++);
 114   while (i--)
 115     lst = scm_cons (scm_mem2string (argv[i], strlen (argv[i])), lst);
 116   return lst;
 117 }
 118
 119
 120 /* This function must only be applied to memory obtained via malloc,
 121    since the GC is going to apply `free' to it when the string is
 122    dropped.
 123
 124    Also, s[len] must be `\0', since we promise that strings are
 125    null-terminated.  Perhaps we could handle non-null-terminated
 126    strings by claiming they're shared substrings of a string we just
 127    made up.  */
 128 SCM
 129 scm_take_str (char *s, size_t len)
 130 #define FUNC_NAME "scm_take_str"
 131 {
 132   SCM answer;
 133
 134   SCM_ASSERT_RANGE (2, scm_ulong2num (len), len <= SCM_STRING_MAX_LENGTH);
 135
 136   SCM_NEWCELL (answer);
 137   SCM_SET_STRING_CHARS (answer, s);
 138   SCM_SET_STRING_LENGTH (answer, len);
 139   scm_done_malloc (len + 1);
 140
 141   return answer;
 142 }
 143 #undef FUNC_NAME
 144
 145
 146 /* `s' must be a malloc'd string.  See scm_take_str.  */
 147 SCM
 148 scm_take0str (char *s)
 149 {
 150   return scm_take_str (s, strlen (s));
 151 }
 152
 153
 154 SCM
 155 scm_mem2string (const char *src, size_t len)
 156 {
 157   SCM s = scm_allocate_string (len);
 158   char *dst = SCM_STRING_CHARS (s);
 159
 160   while (len--)
 161     *dst++ = *src++;
 162   return s;
 163 }
 164
 165
 166 SCM
 167 scm_str2string (const char *src)
 168 {
 169   return scm_mem2string (src, strlen (src));
 170 }
 171
 172
 173 SCM
 174 scm_makfrom0str (const char *src)
 175 {
 176   if (!src) return SCM_BOOL_F;
 177   return scm_mem2string (src, strlen (src));
 178 }
 179
 180
 181 SCM
 182 scm_makfrom0str_opt (const char *src)
 183 {
 184   return scm_makfrom0str (src);
 185 }
 186
 187
 188 SCM
 189 scm_allocate_string (size_t len)
 190 #define FUNC_NAME "scm_allocate_string"
 191 {
 192   char *mem;
 193   SCM s;
 194
 195   SCM_ASSERT_RANGE (1, scm_long2num (len), len <= SCM_STRING_MAX_LENGTH);
 196
 197   mem = (char *) scm_must_malloc (len + 1, FUNC_NAME);
 198   mem[len] = 0;
 199
 200   SCM_NEWCELL (s);
 201   SCM_SET_STRING_CHARS (s, mem);
 202   SCM_SET_STRING_LENGTH (s, len);
 203
 204   return s;
 205 }
 206 #undef FUNC_NAME
 207
 208
 209 SCM_DEFINE (scm_make_string, "make-string", 1, 1, 0,
 210             (SCM k, SCM chr),
 211             "Return a newly allocated string of\n"
 212             "length @var{k}.  If @var{chr} is given, then all elements of\n"
 213             "the string are initialized to @var{chr}, otherwise the contents\n"
 214             "of the @var{string} are unspecified.")
 215 #define FUNC_NAME s_scm_make_string
 216 {
 217   if (SCM_INUMP (k))
 218     {
 219       long int i = SCM_INUM (k);
 220       SCM res;
 221
 222       SCM_ASSERT_RANGE (1, k, i >= 0);
 223
 224       res = scm_allocate_string (i);
 225       if (!SCM_UNBNDP (chr))
 226         {
 227           unsigned char *dst;
 228
 229           SCM_VALIDATE_CHAR (2, chr);
 230
 231           dst = SCM_STRING_UCHARS (res);
 232           memset (dst, SCM_CHAR (chr), i);
 233         }
 234
 235       return res;
 236     }
 237   else if (SCM_BIGP (k))
 238     SCM_OUT_OF_RANGE (1, k);
 239   else
 240     SCM_WRONG_TYPE_ARG (1, k);
 241 }
 242 #undef FUNC_NAME
 243
 244
 245 SCM_DEFINE (scm_string_length, "string-length", 1, 0, 0,
 246             (SCM string),
 247             "Return the number of characters in @var{string}.")
 248 #define FUNC_NAME s_scm_string_length
 249 {
 250   SCM_VALIDATE_STRING (1, string);
 251   return SCM_MAKINUM (SCM_STRING_LENGTH (string));
 252 }
 253 #undef FUNC_NAME
 254
 255 SCM_DEFINE (scm_string_ref, "string-ref", 2, 0, 0,
 256             (SCM str, SCM k),
 257             "Return character @var{k} of @var{str} using zero-origin\n"
 258             "indexing. @var{k} must be a valid index of @var{str}.")
 259 #define FUNC_NAME s_scm_string_ref
 260 {
 261   long idx;
 262
 263   SCM_VALIDATE_STRING (1, str);
 264   SCM_VALIDATE_INUM_COPY (2, k, idx);
 265   SCM_ASSERT_RANGE (2, k, idx >= 0 && idx < SCM_STRING_LENGTH (str));
 266   return SCM_MAKE_CHAR (SCM_STRING_UCHARS (str)[idx]);
 267 }
 268 #undef FUNC_NAME
 269
 270
 271 SCM_DEFINE (scm_string_set_x, "string-set!", 3, 0, 0,
 272             (SCM str, SCM k, SCM chr),
 273             "Store @var{chr} in element @var{k} of @var{str} and return\n"
 274             "an unspecified value. @var{k} must be a valid index of\n"
 275             "@var{str}.")
 276 #define FUNC_NAME s_scm_string_set_x
 277 {
 278   SCM_VALIDATE_STRING (1, str);
 279   SCM_VALIDATE_INUM_RANGE (2,k,0,SCM_STRING_LENGTH(str));
 280   SCM_VALIDATE_CHAR (3,chr);
 281   SCM_STRING_UCHARS (str)[SCM_INUM (k)] = SCM_CHAR (chr);
 282   return SCM_UNSPECIFIED;
 283 }
 284 #undef FUNC_NAME
 285
 286
 287 SCM_DEFINE (scm_substring, "substring", 2, 1, 0,
 288             (SCM str, SCM start, SCM end),
 289             "Return a newly allocated string formed from the characters\n"
 290             "of @var{str} beginning with index @var{start} (inclusive) and\n"
 291             "ending with index @var{end} (exclusive).\n"
 292             "@var{str} must be a string, @var{start} and @var{end} must be\n"
 293             "exact integers satisfying:\n\n"
 294             "0 <= @var{start} <= @var{end} <= (string-length @var{str}).")
 295 #define FUNC_NAME s_scm_substring
 296 {
 297   long int from;
 298   long int to;
 299   SCM substr;
 300
 301   SCM_VALIDATE_STRING (1, str);
 302   SCM_VALIDATE_INUM (2, start);
 303   SCM_VALIDATE_INUM_DEF (3, end, SCM_STRING_LENGTH (str));
 304
 305   from = SCM_INUM (start);
 306   SCM_ASSERT_RANGE (2, start, 0 <= from && from <= SCM_STRING_LENGTH (str));
 307   to = SCM_INUM (end);
 308   SCM_ASSERT_RANGE (3, end, from <= to && to <= SCM_STRING_LENGTH (str));
 309
 310   substr = scm_mem2string (&SCM_STRING_CHARS (str)[from], to - from);
 311   scm_remember_upto_here_1 (str);
 312   return substr;
 313 }
 314 #undef FUNC_NAME
 315
 316
 317 SCM_DEFINE (scm_string_append, "string-append", 0, 0, 1,
 318             (SCM args),
 319             "Return a newly allocated string whose characters form the\n"
 320             "concatenation of the given strings, @var{args}.")
 321 #define FUNC_NAME s_scm_string_append
 322 {
 323   SCM res;
 324   size_t i = 0;
 325   register SCM l, s;
 326   register unsigned char *data;
 327
 328   SCM_VALIDATE_REST_ARGUMENT (args);
 329   for (l = args; !SCM_NULLP (l); l = SCM_CDR (l)) {
 330     s = SCM_CAR (l);
 331     SCM_VALIDATE_STRING (SCM_ARGn,s);
 332     i += SCM_STRING_LENGTH (s);
 333   }
 334   res = scm_allocate_string (i);
 335   data = SCM_STRING_UCHARS (res);
 336   for (l = args; !SCM_NULLP (l);l = SCM_CDR (l)) {
 337     s = SCM_CAR (l);
 338     for (i = 0;i<SCM_STRING_LENGTH (s);i++) *data++ = SCM_STRING_UCHARS (s)[i];
 339   }
 340   return res;
 341 }
 342 #undef FUNC_NAME
 343
 344
 345 void
 346 scm_init_strings ()
 347 {
 348   scm_nullstr = scm_allocate_string (0);
 349
 350 #ifndef SCM_MAGIC_SNARFER
 351 #include "libguile/strings.x"
 352 #endif
 353 }
 354
 355
 356 /*
 357   Local Variables:
 358   c-file-style: "gnu"
 359   End:
 360 */