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Silly grammatical mistake.
[mLib] / dstr.c
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0875b58f 1/* -*-c-*-
2 *
002eaee3 3 * $Id: dstr.c,v 1.10 1999/10/04 21:44:47 mdw Exp $
0875b58f 4 *
5 * Handle dynamically growing strings
6 *
7 * (c) 1998 Straylight/Edgeware
8 */
9
c846879c 10/*----- Licensing notice --------------------------------------------------*
0875b58f 11 *
12 * This file is part of the mLib utilities library.
13 *
14 * mLib is free software; you can redistribute it and/or modify
c846879c 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.
18 *
0875b58f 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
c846879c 22 * GNU Library General Public License for more details.
23 *
24 * You should have received a copy of the GNU Library General Public
0bd98442 25 * License along with mLib; if not, write to the Free
26 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
27 * MA 02111-1307, USA.
0875b58f 28 */
29
30/*----- Revision history --------------------------------------------------*
31 *
32 * $Log: dstr.c,v $
002eaee3 33 * Revision 1.10 1999/10/04 21:44:47 mdw
34 * Move `dstr_putf' and `dstr_vputf' into a separate source file.
35 *
3ca4c9f8 36 * Revision 1.9 1999/07/06 19:16:06 mdw
37 * Simplify buffer-growing algorithm. Just double it each time.
38 *
0fbb1412 39 * Revision 1.8 1999/06/01 09:47:52 mdw
40 * Fix nasty bugs in `dstr_vputf'.
41 *
0bfb1431 42 * Revision 1.7 1999/05/21 22:14:30 mdw
43 * Take advantage of the new dynamic string macros.
44 *
fb467548 45 * Revision 1.6 1999/05/21 08:38:33 mdw
46 * Implement some more functions in terms of macros.
47 *
96c5fe33 48 * Revision 1.5 1999/05/13 22:47:57 mdw
49 * Misc documentation fixes. Change `-ise' to `-ize' throughout.
50 *
0bd98442 51 * Revision 1.4 1999/05/06 19:51:35 mdw
52 * Reformatted the LGPL notice a little bit.
53 *
c846879c 54 * Revision 1.3 1999/05/05 18:50:31 mdw
55 * Change licensing conditions to LGPL.
56 *
00c7638b 57 * Revision 1.2 1998/12/15 23:53:22 mdw
58 * New functions `dstr_putf' and `dstr_vputf' which do `printf'-style
59 * formatting in a safe way.
60 *
61 * Revision 1.1.1.1 1998/06/17 23:44:42 mdw
62 * Initial version of mLib
0875b58f 63 *
64 */
65
66/*----- Header files ------------------------------------------------------*/
67
68#include <stdio.h>
69#include <stdlib.h>
70#include <string.h>
71
72#include "alloc.h"
73#include "dstr.h"
74
75/*----- Tunable constants -------------------------------------------------*/
76
002eaee3 77/*
3ca4c9f8 78 * If the buffer is empty, it is set to @DSTR_INITSZ@ bytes in size.
79 * Otherwise, it's set to the next power of two that's large enough. This is
80 * memory-hungry, but efficient.
81 */
82
0875b58f 83#define DSTR_INITSZ 256 /* Initial buffer size */
3ca4c9f8 84
0875b58f 85/*----- Main code ---------------------------------------------------------*/
86
87/* --- @dstr_create@ --- *
88 *
89 * Arguments: @dstr *d@ = pointer to a dynamic string block
90 *
91 * Returns: ---
92 *
96c5fe33 93 * Use: Initializes a dynamic string.
0875b58f 94 */
95
fb467548 96void dstr_create(dstr *d) { DCREATE(d); }
0875b58f 97
98/* --- @dstr_destroy@ --- *
99 *
100 * Arguments: @dstr *d@ = pointer to a dynamic string block
101 *
102 * Returns: ---
103 *
104 * Use: Reclaims the space used by a dynamic string.
105 */
106
fb467548 107void dstr_destroy(dstr *d) { DDESTROY(d); }
0875b58f 108
109/* --- @dstr_reset@ --- *
110 *
111 * Arguments: @dstr *d@ = pointer to a dynaimc string block
112 *
113 * Returns: ---
114 *
115 * Use: Resets a string so that new data gets put at the beginning.
116 */
117
fb467548 118void dstr_reset(dstr *d) { DRESET(d); }
0875b58f 119
120/* --- @dstr_ensure@ --- *
121 *
122 * Arguments: @dstr *d@ = pointer to a dynamic string block
123 * @size_t sz@ = amount of free space to ensure
124 *
125 * Returns: ---
126 *
127 * Use: Ensures that at least @sz@ bytes are available in the
128 * given string.
129 */
130
131void dstr_ensure(dstr *d, size_t sz)
132{
133 size_t rq = d->len + sz;
134 size_t nsz;
135
136 /* --- If we have enough space, just leave it --- */
137
138 if (rq <= d->sz)
139 return;
140
3ca4c9f8 141 /* --- Grow the buffer --- */
0875b58f 142
143 nsz = d->sz;
144
3ca4c9f8 145 if (nsz == 0 && rq < DSTR_INITSZ)
146 nsz = DSTR_INITSZ;
147 else
148 do nsz <<= 1; while (nsz < rq);
0875b58f 149
150 if (d->buf)
151 d->buf = xrealloc(d->buf, nsz);
152 else
153 d->buf = xmalloc(nsz);
154 d->sz = nsz;
155}
156
157/* --- @dstr_putc@ --- *
158 *
159 * Arguments: @dstr *d@ = pointer to a dynamic string block
160 * @char ch@ = character to append
161 *
162 * Returns: ---
163 *
164 * Use: Appends a character to a string.
165 */
166
fb467548 167void dstr_putc(dstr *d, char ch) { DPUTC(d, ch); }
0875b58f 168
169/* --- @dstr_putz@ --- *
170 *
171 * Arguments: @dstr *d@ = pointer to a dynamic string block
172 *
173 * Returns: ---
174 *
175 * Use: Appends a null byte to a string. The null byte does not
176 * contribute to the string's length, and will be overwritten
177 * by subsequent `put' operations.
178 */
179
fb467548 180void dstr_putz(dstr *d) { DPUTZ(d); }
0875b58f 181
182/* --- @dstr_puts@ --- *
183 *
184 * Arguments: @dstr *d@ = pointer to a dynamic string block
185 * @const char *s@ = pointer to string to append
186 *
187 * Returns: ---
188 *
189 * Use: Appends a character string to a string. A trailing null
190 * byte is added, as for @dstr_putz@.
191 */
192
fb467548 193void dstr_puts(dstr *d, const char *s) { DPUTS(d, s); }
0875b58f 194
195/* --- @dstr_putd@ --- *
196 *
197 * Arguments: @dstr *d@ = pointer to a dynamic string block
198 * @const dstr *s@ = pointer to a dynamic string to append
199 *
200 * Returns: ---
201 *
202 * Use: Appends a dynamic string to a string. A trailing null
203 * byte is added, as for @dstr_putz@.
204 */
205
fb467548 206void dstr_putd(dstr *d, const dstr *s) { DPUTD(d, s); }
0875b58f 207
208/* --- @dstr_putm@ --- *
209 *
210 * Arguments: @dstr *d@ = pointer to a dynamic string block
211 * @const void *p@ = pointer to a block to append
212 * @size_t sz@ = size of the block
213 *
214 * Returns: Appends an arbitrary data block to a string. No trailing
215 * null is appended.
216 */
217
fb467548 218void dstr_putm(dstr *d, const void *p, size_t sz) { DPUTM(d, p, sz); }
0875b58f 219
220/* --- @dstr_tidy@ --- *
221 *
222 * Arguments: @dstr *d@ = pointer to a dynamic string block
223 *
224 * Returns: ---
225 *
226 * Use: Reduces the amount of memory used by a string. A trailing
227 * null byte is added, as for @dstr_putz@.
228 */
229
230void dstr_tidy(dstr *d)
231{
232 dstr_putz(d);
233 d->buf = xrealloc(d->buf, d->len + 1);
234 d->sz = d->len + 1;
235}
236
237/* --- @dstr_putline@ --- *
238 *
239 * Arguments: @dstr *d@ = pointer to a dynamic string block
240 * @FILE *fp@ = a stream to read from
241 *
242 * Returns: The number of characters read into the buffer, or @EOF@ if
243 * end-of-file was reached before any characters were read.
244 *
245 * Use: Appends the next line from the given input stream to the
246 * string. A trailing newline is not added; a trailing null
247 * byte is appended, as for @dstr_putz@.
248 */
249
250int dstr_putline(dstr *d, FILE *fp)
251{
252 size_t left = d->sz - d->len;
253 size_t off = d->len;
254 int rd = 0;
255 int ch;
256
257 for (;;) {
258
259 /* --- Make sure there's some buffer space --- */
260
261 if (!left) {
262 dstr_ensure(d, 1);
263 left = d->sz - off;
264 }
265
266 /* --- Read the next byte --- */
267
268 ch = getc(fp);
269
270 /* --- End-of-file when no characters read is special --- */
271
272 if (ch == EOF && !rd)
273 return (EOF);
274
275 /* --- End-of-file or newline ends the loop --- */
276
277 if (ch == EOF || ch == '\n') {
278 d->buf[off] = 0;
279 d->len = off;
280 return rd;
281 }
282
283 /* --- Append the character and continue --- */
284
285 d->buf[off++] = ch;
286 left--; rd++;
287 }
288}
289
290/* --- @dstr_write@ --- *
291 *
292 * Arguments: @dstr *d@ = pointer to a dynamic string block
293 * @FILE *fp@ = a stream to write on
294 *
295 * Returns: The number of bytes written (as for @fwrite@).
296 *
297 * Use: Writes a dynamic string to a file.
298 */
299
fb467548 300size_t dstr_write(const dstr *d, FILE *fp) { return (DWRITE(d, fp)); }
0875b58f 301
302/*----- That's all, folks -------------------------------------------------*/