1 /* GLIB - Library of useful routines for C programming
2 * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
19 * Modified by the GLib Team and others 1997-2000. See the AUTHORS
20 * file for a list of people on the GLib Team. See the ChangeLog
21 * files for a list of changes. These files are distributed with
22 * GLib at ftp://ftp.gtk.org/pub/gtk/.
45 * @short_description: text buffers which grow automatically
48 * A #GString is an object that handles the memory management of a C
49 * string for you. The emphasis of #GString is on text, typically
50 * UTF-8. Crucially, the "str" member of a #GString is guaranteed to
51 * have a trailing nul character, and it is therefore always safe to
52 * call functions such as strchr() or g_strdup() on it.
54 * However, a #GString can also hold arbitrary binary data, because it
55 * has a "len" member, which includes any possible embedded nul
56 * characters in the data. Conceptually then, #GString is like a
57 * #GByteArray with the addition of many convenience methods for text,
58 * and a guaranteed nul terminator.
63 * @str: points to the character data. It may move as text is added.
64 * The @str field is null-terminated and so
65 * can be used as an ordinary C string.
66 * @len: contains the length of the string, not including the
67 * terminating nul byte.
68 * @allocated_len: the number of bytes that can be stored in the
69 * string before it needs to be reallocated. May be larger than @len.
71 * The GString struct contains the public fields of a GString.
75 #define MY_MAXSIZE ((gsize)-1)
78 nearest_power (gsize base, gsize num)
80 if (num > MY_MAXSIZE / 2)
96 g_string_maybe_expand (GString *string,
99 if (string->len + len >= string->allocated_len)
101 string->allocated_len = nearest_power (1, string->len + len + 1);
102 string->str = g_realloc (string->str, string->allocated_len);
107 * g_string_sized_new:
108 * @dfl_size: the default size of the space allocated to
111 * Creates a new #GString, with enough space for @dfl_size
112 * bytes. This is useful if you are going to add a lot of
113 * text to the string and don't want it to be reallocated
116 * Returns: the new #GString
119 g_string_sized_new (gsize dfl_size)
121 GString *string = g_slice_new (GString);
123 string->allocated_len = 0;
127 g_string_maybe_expand (string, MAX (dfl_size, 2));
135 * @init: (allow-none): the initial text to copy into the string, or %NULL to
136 * start with an empty string.
138 * Creates a new #GString, initialized with the given string.
140 * Returns: the new #GString
143 g_string_new (const gchar *init)
147 if (init == NULL || *init == '\0')
148 string = g_string_sized_new (2);
154 string = g_string_sized_new (len + 2);
156 g_string_append_len (string, init, len);
164 * @init: initial contents of the string
165 * @len: length of @init to use
167 * Creates a new #GString with @len bytes of the @init buffer.
168 * Because a length is provided, @init need not be nul-terminated,
169 * and can contain embedded nul bytes.
171 * Since this function does not stop at nul bytes, it is the caller's
172 * responsibility to ensure that @init has at least @len addressable
175 * Returns: a new #GString
178 g_string_new_len (const gchar *init,
184 return g_string_new (init);
187 string = g_string_sized_new (len);
190 g_string_append_len (string, init, len);
198 * @string: a #GString
199 * @free_segment: if %TRUE, the actual character data is freed as well
201 * Frees the memory allocated for the #GString.
202 * If @free_segment is %TRUE it also frees the character data. If
203 * it's %FALSE, the caller gains ownership of the buffer and must
204 * free it after use with g_free().
206 * Returns: the character data of @string
207 * (i.e. %NULL if @free_segment is %TRUE)
210 g_string_free (GString *string,
211 gboolean free_segment)
215 g_return_val_if_fail (string != NULL, NULL);
219 g_free (string->str);
223 segment = string->str;
225 g_slice_free (GString, string);
231 * g_string_free_to_bytes:
232 * @string: (transfer full): a #GString
234 * Transfers ownership of the contents of @string to a newly allocated
235 * #GBytes. The #GString structure itself is deallocated, and it is
236 * therefore invalid to use @string after invoking this function.
238 * Note that while #GString ensures that its buffer always has a
239 * trailing nul character (not reflected in its "len"), the returned
240 * #GBytes does not include this extra nul; i.e. it has length exactly
241 * equal to the "len" member.
243 * Returns: A newly allocated #GBytes containing contents of @string; @string itself is freed
247 g_string_free_to_bytes (GString *string)
252 g_return_val_if_fail (string != NULL, NULL);
256 buf = g_string_free (string, FALSE);
258 return g_bytes_new_take (buf, len);
264 * @v2: another #GString
266 * Compares two strings for equality, returning %TRUE if they are equal.
267 * For use with #GHashTable.
269 * Returns: %TRUE if the strings are the same length and contain the
273 g_string_equal (const GString *v,
277 GString *string1 = (GString *) v;
278 GString *string2 = (GString *) v2;
279 gsize i = string1->len;
281 if (i != string2->len)
299 * @str: a string to hash
301 * Creates a hash code for @str; for use with #GHashTable.
303 * Returns: hash code for @str
306 g_string_hash (const GString *str)
308 const gchar *p = str->str;
312 /* 31 bit hash function */
315 h = (h << 5) - h + *p;
324 * @string: the destination #GString. Its current contents
326 * @rval: the string to copy into @string
328 * Copies the bytes from a string into a #GString,
329 * destroying any previous contents. It is rather like
330 * the standard strcpy() function, except that you do not
331 * have to worry about having enough space to copy the string.
336 g_string_assign (GString *string,
339 g_return_val_if_fail (string != NULL, NULL);
340 g_return_val_if_fail (rval != NULL, string);
342 /* Make sure assigning to itself doesn't corrupt the string. */
343 if (string->str != rval)
345 /* Assigning from substring should be ok, since
346 * g_string_truncate() does not reallocate.
348 g_string_truncate (string, 0);
349 g_string_append (string, rval);
357 * @string: a #GString
358 * @len: the new size of @string
360 * Cuts off the end of the GString, leaving the first @len bytes.
365 g_string_truncate (GString *string,
368 g_return_val_if_fail (string != NULL, NULL);
370 string->len = MIN (len, string->len);
371 string->str[string->len] = 0;
378 * @string: a #GString
379 * @len: the new length
381 * Sets the length of a #GString. If the length is less than
382 * the current length, the string will be truncated. If the
383 * length is greater than the current length, the contents
384 * of the newly added area are undefined. (However, as
385 * always, string->str[string->len] will be a nul byte.)
390 g_string_set_size (GString *string,
393 g_return_val_if_fail (string != NULL, NULL);
395 if (len >= string->allocated_len)
396 g_string_maybe_expand (string, len - string->len);
399 string->str[len] = 0;
405 * g_string_insert_len:
406 * @string: a #GString
407 * @pos: position in @string where insertion should
408 * happen, or -1 for at the end
409 * @val: bytes to insert
410 * @len: number of bytes of @val to insert
412 * Inserts @len bytes of @val into @string at @pos.
413 * Because @len is provided, @val may contain embedded
414 * nuls and need not be nul-terminated. If @pos is -1,
415 * bytes are inserted at the end of the string.
417 * Since this function does not stop at nul bytes, it is
418 * the caller's responsibility to ensure that @val has at
419 * least @len addressable bytes.
424 g_string_insert_len (GString *string,
429 g_return_val_if_fail (string != NULL, NULL);
430 g_return_val_if_fail (len == 0 || val != NULL, string);
441 g_return_val_if_fail (pos <= string->len, string);
443 /* Check whether val represents a substring of string.
444 * This test probably violates chapter and verse of the C standards,
445 * since ">=" and "<=" are only valid when val really is a substring.
446 * In practice, it will work on modern archs.
448 if (val >= string->str && val <= string->str + string->len)
450 gsize offset = val - string->str;
453 g_string_maybe_expand (string, len);
454 val = string->str + offset;
455 /* At this point, val is valid again. */
457 /* Open up space where we are going to insert. */
458 if (pos < string->len)
459 memmove (string->str + pos + len, string->str + pos, string->len - pos);
461 /* Move the source part before the gap, if any. */
464 precount = MIN (len, pos - offset);
465 memcpy (string->str + pos, val, precount);
468 /* Move the source part after the gap, if any. */
470 memcpy (string->str + pos + precount,
471 val + /* Already moved: */ precount + /* Space opened up: */ len,
476 g_string_maybe_expand (string, len);
478 /* If we aren't appending at the end, move a hunk
479 * of the old string to the end, opening up space
481 if (pos < string->len)
482 memmove (string->str + pos + len, string->str + pos, string->len - pos);
484 /* insert the new string */
486 string->str[pos] = *val;
488 memcpy (string->str + pos, val, len);
493 string->str[string->len] = 0;
498 #define SUB_DELIM_CHARS "!$&'()*+,;="
502 const char *reserved_chars_allowed)
504 if (g_ascii_isalnum (c) ||
511 if (reserved_chars_allowed &&
512 strchr (reserved_chars_allowed, c) != NULL)
519 gunichar_ok (gunichar c)
522 (c != (gunichar) -2) &&
523 (c != (gunichar) -1);
527 * g_string_append_uri_escaped:
528 * @string: a #GString
529 * @unescaped: a string
530 * @reserved_chars_allowed: a string of reserved characters allowed
531 * to be used, or %NULL
532 * @allow_utf8: set %TRUE if the escaped string may include UTF8 characters
534 * Appends @unescaped to @string, escaped any characters that
535 * are reserved in URIs using URI-style escape sequences.
542 g_string_append_uri_escaped (GString *string,
543 const gchar *unescaped,
544 const gchar *reserved_chars_allowed,
549 static const gchar hex[16] = "0123456789ABCDEF";
551 g_return_val_if_fail (string != NULL, NULL);
552 g_return_val_if_fail (unescaped != NULL, NULL);
554 end = unescaped + strlen (unescaped);
556 while ((c = *unescaped) != 0)
558 if (c >= 0x80 && allow_utf8 &&
559 gunichar_ok (g_utf8_get_char_validated (unescaped, end - unescaped)))
561 int len = g_utf8_skip [c];
562 g_string_append_len (string, unescaped, len);
565 else if (is_valid (c, reserved_chars_allowed))
567 g_string_append_c (string, c);
572 g_string_append_c (string, '%');
573 g_string_append_c (string, hex[((guchar)c) >> 4]);
574 g_string_append_c (string, hex[((guchar)c) & 0xf]);
584 * @string: a #GString
585 * @val: the string to append onto the end of @string
587 * Adds a string onto the end of a #GString, expanding
593 g_string_append (GString *string,
596 g_return_val_if_fail (string != NULL, NULL);
597 g_return_val_if_fail (val != NULL, string);
599 return g_string_insert_len (string, -1, val, -1);
603 * g_string_append_len:
604 * @string: a #GString
605 * @val: bytes to append
606 * @len: number of bytes of @val to use
608 * Appends @len bytes of @val to @string. Because @len is
609 * provided, @val may contain embedded nuls and need not
612 * Since this function does not stop at nul bytes, it is
613 * the caller's responsibility to ensure that @val has at
614 * least @len addressable bytes.
619 g_string_append_len (GString *string,
623 g_return_val_if_fail (string != NULL, NULL);
624 g_return_val_if_fail (len == 0 || val != NULL, string);
626 return g_string_insert_len (string, -1, val, len);
631 * @string: a #GString
632 * @c: the byte to append onto the end of @string
634 * Adds a byte onto the end of a #GString, expanding
639 #undef g_string_append_c
641 g_string_append_c (GString *string,
644 g_return_val_if_fail (string != NULL, NULL);
646 return g_string_insert_c (string, -1, c);
650 * g_string_append_unichar:
651 * @string: a #GString
652 * @wc: a Unicode character
654 * Converts a Unicode character into UTF-8, and appends it
660 g_string_append_unichar (GString *string,
663 g_return_val_if_fail (string != NULL, NULL);
665 return g_string_insert_unichar (string, -1, wc);
670 * @string: a #GString
671 * @val: the string to prepend on the start of @string
673 * Adds a string on to the start of a #GString,
674 * expanding it if necessary.
679 g_string_prepend (GString *string,
682 g_return_val_if_fail (string != NULL, NULL);
683 g_return_val_if_fail (val != NULL, string);
685 return g_string_insert_len (string, 0, val, -1);
689 * g_string_prepend_len:
690 * @string: a #GString
691 * @val: bytes to prepend
692 * @len: number of bytes in @val to prepend
694 * Prepends @len bytes of @val to @string.
695 * Because @len is provided, @val may contain
696 * embedded nuls and need not be nul-terminated.
698 * Since this function does not stop at nul bytes,
699 * it is the caller's responsibility to ensure that
700 * @val has at least @len addressable bytes.
705 g_string_prepend_len (GString *string,
709 g_return_val_if_fail (string != NULL, NULL);
710 g_return_val_if_fail (val != NULL, string);
712 return g_string_insert_len (string, 0, val, len);
716 * g_string_prepend_c:
717 * @string: a #GString
718 * @c: the byte to prepend on the start of the #GString
720 * Adds a byte onto the start of a #GString,
721 * expanding it if necessary.
726 g_string_prepend_c (GString *string,
729 g_return_val_if_fail (string != NULL, NULL);
731 return g_string_insert_c (string, 0, c);
735 * g_string_prepend_unichar:
736 * @string: a #GString
737 * @wc: a Unicode character
739 * Converts a Unicode character into UTF-8, and prepends it
745 g_string_prepend_unichar (GString *string,
748 g_return_val_if_fail (string != NULL, NULL);
750 return g_string_insert_unichar (string, 0, wc);
755 * @string: a #GString
756 * @pos: the position to insert the copy of the string
757 * @val: the string to insert
759 * Inserts a copy of a string into a #GString,
760 * expanding it if necessary.
765 g_string_insert (GString *string,
769 g_return_val_if_fail (string != NULL, NULL);
770 g_return_val_if_fail (val != NULL, string);
773 g_return_val_if_fail (pos <= string->len, string);
775 return g_string_insert_len (string, pos, val, -1);
780 * @string: a #GString
781 * @pos: the position to insert the byte
782 * @c: the byte to insert
784 * Inserts a byte into a #GString, expanding it if necessary.
789 g_string_insert_c (GString *string,
793 g_return_val_if_fail (string != NULL, NULL);
795 g_string_maybe_expand (string, 1);
800 g_return_val_if_fail (pos <= string->len, string);
802 /* If not just an append, move the old stuff */
803 if (pos < string->len)
804 memmove (string->str + pos + 1, string->str + pos, string->len - pos);
806 string->str[pos] = c;
810 string->str[string->len] = 0;
816 * g_string_insert_unichar:
817 * @string: a #GString
818 * @pos: the position at which to insert character, or -1
819 * to append at the end of the string
820 * @wc: a Unicode character
822 * Converts a Unicode character into UTF-8, and insert it
823 * into the string at the given position.
828 g_string_insert_unichar (GString *string,
832 gint charlen, first, i;
835 g_return_val_if_fail (string != NULL, NULL);
837 /* Code copied from g_unichar_to_utf() */
848 else if (wc < 0x10000)
853 else if (wc < 0x200000)
858 else if (wc < 0x4000000)
868 /* End of copied code */
870 g_string_maybe_expand (string, charlen);
875 g_return_val_if_fail (pos <= string->len, string);
877 /* If not just an append, move the old stuff */
878 if (pos < string->len)
879 memmove (string->str + pos + charlen, string->str + pos, string->len - pos);
881 dest = string->str + pos;
882 /* Code copied from g_unichar_to_utf() */
883 for (i = charlen - 1; i > 0; --i)
885 dest[i] = (wc & 0x3f) | 0x80;
888 dest[0] = wc | first;
889 /* End of copied code */
891 string->len += charlen;
893 string->str[string->len] = 0;
899 * g_string_overwrite:
900 * @string: a #GString
901 * @pos: the position at which to start overwriting
902 * @val: the string that will overwrite the @string starting at @pos
904 * Overwrites part of a string, lengthening it if necessary.
911 g_string_overwrite (GString *string,
915 g_return_val_if_fail (val != NULL, string);
916 return g_string_overwrite_len (string, pos, val, strlen (val));
920 * g_string_overwrite_len:
921 * @string: a #GString
922 * @pos: the position at which to start overwriting
923 * @val: the string that will overwrite the @string starting at @pos
924 * @len: the number of bytes to write from @val
926 * Overwrites part of a string, lengthening it if necessary.
927 * This function will work with embedded nuls.
934 g_string_overwrite_len (GString *string,
941 g_return_val_if_fail (string != NULL, NULL);
946 g_return_val_if_fail (val != NULL, string);
947 g_return_val_if_fail (pos <= string->len, string);
954 if (end > string->len)
955 g_string_maybe_expand (string, end - string->len);
957 memcpy (string->str + pos, val, len);
959 if (end > string->len)
961 string->str[end] = '\0';
970 * @string: a #GString
971 * @pos: the position of the content to remove
972 * @len: the number of bytes to remove, or -1 to remove all
975 * Removes @len bytes from a #GString, starting at position @pos.
976 * The rest of the #GString is shifted down to fill the gap.
981 g_string_erase (GString *string,
985 g_return_val_if_fail (string != NULL, NULL);
986 g_return_val_if_fail (pos >= 0, string);
987 g_return_val_if_fail (pos <= string->len, string);
990 len = string->len - pos;
993 g_return_val_if_fail (pos + len <= string->len, string);
995 if (pos + len < string->len)
996 memmove (string->str + pos, string->str + pos + len, string->len - (pos + len));
1001 string->str[string->len] = 0;
1007 * g_string_ascii_down:
1008 * @string: a GString
1010 * Converts all uppercase ASCII letters to lowercase ASCII letters.
1012 * Returns: passed-in @string pointer, with all the
1013 * uppercase characters converted to lowercase in place,
1014 * with semantics that exactly match g_ascii_tolower().
1017 g_string_ascii_down (GString *string)
1022 g_return_val_if_fail (string != NULL, NULL);
1029 *s = g_ascii_tolower (*s);
1038 * g_string_ascii_up:
1039 * @string: a GString
1041 * Converts all lowercase ASCII letters to uppercase ASCII letters.
1043 * Returns: passed-in @string pointer, with all the
1044 * lowercase characters converted to uppercase in place,
1045 * with semantics that exactly match g_ascii_toupper().
1048 g_string_ascii_up (GString *string)
1053 g_return_val_if_fail (string != NULL, NULL);
1060 *s = g_ascii_toupper (*s);
1070 * @string: a #GString
1072 * Converts a #GString to lowercase.
1074 * Returns: the #GString
1076 * Deprecated:2.2: This function uses the locale-specific
1077 * tolower() function, which is almost never the right thing.
1078 * Use g_string_ascii_down() or g_utf8_strdown() instead.
1081 g_string_down (GString *string)
1086 g_return_val_if_fail (string != NULL, NULL);
1089 s = (guchar *) string->str;
1104 * @string: a #GString
1106 * Converts a #GString to uppercase.
1110 * Deprecated:2.2: This function uses the locale-specific
1111 * toupper() function, which is almost never the right thing.
1112 * Use g_string_ascii_up() or g_utf8_strup() instead.
1115 g_string_up (GString *string)
1120 g_return_val_if_fail (string != NULL, NULL);
1123 s = (guchar *) string->str;
1137 * g_string_append_vprintf:
1138 * @string: a #GString
1139 * @format: the string format. See the printf() documentation
1140 * @args: the list of arguments to insert in the output
1142 * Appends a formatted string onto the end of a #GString.
1143 * This function is similar to g_string_append_printf()
1144 * except that the arguments to the format string are passed
1150 g_string_append_vprintf (GString *string,
1151 const gchar *format,
1157 g_return_if_fail (string != NULL);
1158 g_return_if_fail (format != NULL);
1160 len = g_vasprintf (&buf, format, args);
1164 g_string_maybe_expand (string, len);
1165 memcpy (string->str + string->len, buf, len + 1);
1173 * @string: a #GString
1174 * @format: the string format. See the printf() documentation
1175 * @args: the parameters to insert into the format string
1177 * Writes a formatted string into a #GString.
1178 * This function is similar to g_string_printf() except that
1179 * the arguments to the format string are passed as a va_list.
1184 g_string_vprintf (GString *string,
1185 const gchar *format,
1188 g_string_truncate (string, 0);
1189 g_string_append_vprintf (string, format, args);
1194 * @string: a #GString
1195 * @format: the string format. See the sprintf() documentation
1196 * @...: the parameters to insert into the format string
1198 * Writes a formatted string into a #GString.
1199 * This is similar to the standard sprintf() function,
1200 * except that the #GString buffer automatically expands
1201 * to contain the results. The previous contents of the
1202 * #GString are destroyed.
1204 * Deprecated: This function has been renamed to g_string_printf().
1209 * @string: a #GString
1210 * @format: the string format. See the printf() documentation
1211 * @...: the parameters to insert into the format string
1213 * Writes a formatted string into a #GString.
1214 * This is similar to the standard sprintf() function,
1215 * except that the #GString buffer automatically expands
1216 * to contain the results. The previous contents of the
1217 * #GString are destroyed.
1220 g_string_printf (GString *string,
1221 const gchar *format,
1226 g_string_truncate (string, 0);
1228 va_start (args, format);
1229 g_string_append_vprintf (string, format, args);
1234 * g_string_sprintfa:
1235 * @string: a #GString
1236 * @format: the string format. See the sprintf() documentation
1237 * @...: the parameters to insert into the format string
1239 * Appends a formatted string onto the end of a #GString.
1240 * This function is similar to g_string_sprintf() except that
1241 * the text is appended to the #GString.
1243 * Deprecated: This function has been renamed to g_string_append_printf()
1247 * g_string_append_printf:
1248 * @string: a #GString
1249 * @format: the string format. See the printf() documentation
1250 * @...: the parameters to insert into the format string
1252 * Appends a formatted string onto the end of a #GString.
1253 * This function is similar to g_string_printf() except
1254 * that the text is appended to the #GString.
1257 g_string_append_printf (GString *string,
1258 const gchar *format,
1263 va_start (args, format);
1264 g_string_append_vprintf (string, format, args);