3 * $Id: dstr.c,v 1.14 2000/06/17 10:37:39 mdw Exp $
5 * Handle dynamically growing strings
7 * (c) 1998 Straylight/Edgeware
10 /*----- Licensing notice --------------------------------------------------*
12 * This file is part of the mLib utilities library.
14 * mLib is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU Library General Public License as
16 * published by the Free Software Foundation; either version 2 of the
17 * License, or (at your option) any later version.
19 * mLib is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU Library General Public License for more details.
24 * You should have received a copy of the GNU Library General Public
25 * License along with mLib; if not, write to the Free
26 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
30 /*----- Revision history --------------------------------------------------*
33 * Revision 1.14 2000/06/17 10:37:39 mdw
34 * Add support for arena management.
36 * Revision 1.13 1999/12/22 15:39:28 mdw
37 * Fix overflow in dstr_putline.
39 * Revision 1.12 1999/12/10 23:42:04 mdw
40 * Change header file guard names.
42 * Revision 1.11 1999/10/28 22:05:29 mdw
43 * Modify and debug allocation routines.
45 * Revision 1.10 1999/10/04 21:44:47 mdw
46 * Move `dstr_putf' and `dstr_vputf' into a separate source file.
48 * Revision 1.9 1999/07/06 19:16:06 mdw
49 * Simplify buffer-growing algorithm. Just double it each time.
51 * Revision 1.8 1999/06/01 09:47:52 mdw
52 * Fix nasty bugs in `dstr_vputf'.
54 * Revision 1.7 1999/05/21 22:14:30 mdw
55 * Take advantage of the new dynamic string macros.
57 * Revision 1.6 1999/05/21 08:38:33 mdw
58 * Implement some more functions in terms of macros.
60 * Revision 1.5 1999/05/13 22:47:57 mdw
61 * Misc documentation fixes. Change `-ise' to `-ize' throughout.
63 * Revision 1.4 1999/05/06 19:51:35 mdw
64 * Reformatted the LGPL notice a little bit.
66 * Revision 1.3 1999/05/05 18:50:31 mdw
67 * Change licensing conditions to LGPL.
69 * Revision 1.2 1998/12/15 23:53:22 mdw
70 * New functions `dstr_putf' and `dstr_vputf' which do `printf'-style
71 * formatting in a safe way.
73 * Revision 1.1.1.1 1998/06/17 23:44:42 mdw
74 * Initial version of mLib
78 /*----- Header files ------------------------------------------------------*/
87 /*----- Tunable constants -------------------------------------------------*/
90 * If the buffer is empty, it is set to @DSTR_INITSZ@ bytes in size.
91 * Otherwise, it's set to the next power of two that's large enough. This is
92 * memory-hungry, but efficient.
95 #define DSTR_INITSZ 64 /* Initial buffer size */
97 /*----- Main code ---------------------------------------------------------*/
99 /* --- @dstr_create@ --- *
101 * Arguments: @dstr *d@ = pointer to a dynamic string block
105 * Use: Initializes a dynamic string.
108 void dstr_create(dstr *d) { DCREATE(d); }
110 /* --- @dstr_destroy@ --- *
112 * Arguments: @dstr *d@ = pointer to a dynamic string block
116 * Use: Reclaims the space used by a dynamic string.
119 void dstr_destroy(dstr *d) { DDESTROY(d); }
121 /* --- @dstr_reset@ --- *
123 * Arguments: @dstr *d@ = pointer to a dynamic string block
127 * Use: Resets a string so that new data gets put at the beginning.
130 void dstr_reset(dstr *d) { DRESET(d); }
132 /* --- @dstr_ensure@ --- *
134 * Arguments: @dstr *d@ = pointer to a dynamic string block
135 * @size_t sz@ = amount of free space to ensure
139 * Use: Ensures that at least @sz@ bytes are available in the
143 void dstr_ensure(dstr *d, size_t sz)
145 size_t rq = d->len + sz;
148 /* --- If we have enough space, just leave it --- */
153 /* --- Grow the buffer --- */
158 nsz = (DSTR_INITSZ >> 1);
159 do nsz <<= 1; while (nsz < rq);
162 d->buf = x_realloc(d->a, d->buf, nsz);
164 d->buf = x_alloc(d->a, nsz);
168 /* --- @dstr_putc@ --- *
170 * Arguments: @dstr *d@ = pointer to a dynamic string block
171 * @char ch@ = character to append
175 * Use: Appends a character to a string.
178 void dstr_putc(dstr *d, char ch) { DPUTC(d, ch); }
180 /* --- @dstr_putz@ --- *
182 * Arguments: @dstr *d@ = pointer to a dynamic string block
186 * Use: Appends a null byte to a string. The null byte does not
187 * contribute to the string's length, and will be overwritten
188 * by subsequent `put' operations.
191 void dstr_putz(dstr *d) { DPUTZ(d); }
193 /* --- @dstr_puts@ --- *
195 * Arguments: @dstr *d@ = pointer to a dynamic string block
196 * @const char *s@ = pointer to string to append
200 * Use: Appends a character string to a string. A trailing null
201 * byte is added, as for @dstr_putz@.
204 void dstr_puts(dstr *d, const char *s) { DPUTS(d, s); }
206 /* --- @dstr_putd@ --- *
208 * Arguments: @dstr *d@ = pointer to a dynamic string block
209 * @const dstr *s@ = pointer to a dynamic string to append
213 * Use: Appends a dynamic string to a string. A trailing null
214 * byte is added, as for @dstr_putz@.
217 void dstr_putd(dstr *d, const dstr *s) { DPUTD(d, s); }
219 /* --- @dstr_putm@ --- *
221 * Arguments: @dstr *d@ = pointer to a dynamic string block
222 * @const void *p@ = pointer to a block to append
223 * @size_t sz@ = size of the block
225 * Returns: Appends an arbitrary data block to a string. No trailing
229 void dstr_putm(dstr *d, const void *p, size_t sz) { DPUTM(d, p, sz); }
231 /* --- @dstr_tidy@ --- *
233 * Arguments: @dstr *d@ = pointer to a dynamic string block
237 * Use: Reduces the amount of memory used by a string. A trailing
238 * null byte is added, as for @dstr_putz@.
241 void dstr_tidy(dstr *d)
243 d->buf = x_realloc(d->a, d->buf, d->len + 1);
248 /* --- @dstr_putline@ --- *
250 * Arguments: @dstr *d@ = pointer to a dynamic string block
251 * @FILE *fp@ = a stream to read from
253 * Returns: The number of characters read into the buffer, or @EOF@ if
254 * end-of-file was reached before any characters were read.
256 * Use: Appends the next line from the given input stream to the
257 * string. A trailing newline is not added; a trailing null
258 * byte is appended, as for @dstr_putz@.
261 int dstr_putline(dstr *d, FILE *fp)
263 size_t left = d->sz - d->len;
270 /* --- Read the next byte --- */
274 /* --- End-of-file when no characters read is special --- */
276 if (ch == EOF && !rd)
279 /* --- Make sure there's some buffer space --- */
287 /* --- End-of-file or newline ends the loop --- */
289 if (ch == EOF || ch == '\n') {
295 /* --- Append the character and continue --- */
302 /* --- @dstr_write@ --- *
304 * Arguments: @dstr *d@ = pointer to a dynamic string block
305 * @FILE *fp@ = a stream to write on
307 * Returns: The number of bytes written (as for @fwrite@).
309 * Use: Writes a dynamic string to a file.
312 size_t dstr_write(const dstr *d, FILE *fp) { return (DWRITE(d, fp)); }
314 /*----- That's all, folks -------------------------------------------------*/