7c24b3a8a75733382274d3f34f4ea46a46283f80
1 /*
2 * SysDB - src/utils/strbuf.c
3 * Copyright (C) 2012 Sebastian 'tokkee' Harl <sh@tokkee.org>
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
17 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
18 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR
19 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
20 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
21 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
22 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
23 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
24 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
25 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
28 #include "utils/strbuf.h"
30 #include <assert.h>
32 #include <stdio.h>
33 #include <stdlib.h>
34 #include <stdarg.h>
36 /*
37 * private data structures
38 */
40 struct sdb_strbuf {
41 char *string;
42 size_t size;
43 size_t pos;
44 };
46 /*
47 * private helper functions
48 */
50 static int
51 strbuf_resize(sdb_strbuf_t *strbuf, size_t new_size)
52 {
53 char *tmp;
55 if (new_size <= strbuf->size)
56 return 0;
58 tmp = realloc(strbuf->string, new_size);
59 if (! tmp)
60 return -1;
62 strbuf->string = tmp;
63 strbuf->size = new_size;
64 return 0;
65 } /* strbuf_resize */
67 /*
68 * public API
69 */
71 sdb_strbuf_t *
72 sdb_strbuf_create(size_t size)
73 {
74 sdb_strbuf_t *strbuf;
76 strbuf = calloc(1, sizeof(*strbuf));
77 if (! strbuf)
78 return NULL;
80 strbuf->string = NULL;
81 if (size) {
82 strbuf->string = malloc(size);
83 if (! strbuf->string) {
84 free(strbuf);
85 return NULL;
86 }
88 strbuf->string[0] = '\0';
89 }
91 strbuf->size = size;
92 strbuf->pos = 0;
94 return strbuf;
95 } /* sdb_strbuf_create */
97 void
98 sdb_strbuf_destroy(sdb_strbuf_t *strbuf)
99 {
100 if (! strbuf)
101 return;
103 if (strbuf->string)
104 free(strbuf->string);
105 free(strbuf);
106 } /* sdb_strbuf_destroy */
108 ssize_t
109 sdb_strbuf_vappend(sdb_strbuf_t *strbuf, const char *fmt, va_list ap)
110 {
111 va_list aq;
112 int status;
114 if ((! strbuf) || (! fmt))
115 return -1;
117 assert((strbuf->size == 0) || (strbuf->string[strbuf->pos] == '\0'));
119 if (strbuf->pos >= strbuf->size)
120 /* use some arbitrary but somewhat reasonable default */
121 if (strbuf_resize(strbuf, strbuf->size ? 2 * strbuf->size : 64))
122 return -1;
124 assert(strbuf->size && strbuf->string);
125 assert(strbuf->pos < strbuf->size);
127 /* 'ap' is invalid after calling vsnprintf; thus copy before using it */
128 va_copy(aq, ap);
129 status = vsnprintf(strbuf->string + strbuf->pos,
130 strbuf->size - strbuf->pos, fmt, ap);
132 if (status < 0) {
133 va_end(aq);
134 return status;
135 }
137 if ((size_t)status >= strbuf->size - strbuf->pos) {
138 strbuf_resize(strbuf, (size_t)status + 1);
140 /* reset string and try again */
141 strbuf->string[strbuf->pos] = '\0';
142 status = (int)sdb_strbuf_vappend(strbuf, fmt, aq);
143 }
144 else
145 strbuf->pos += (size_t)status;
147 va_end(aq);
148 return (ssize_t)status;
149 } /* sdb_strbuf_vappend */
151 ssize_t
152 sdb_strbuf_append(sdb_strbuf_t *strbuf, const char *fmt, ...)
153 {
154 va_list ap;
155 ssize_t status;
157 va_start(ap, fmt);
158 status = sdb_strbuf_vappend(strbuf, fmt, ap);
159 va_end(ap);
161 return status;
162 } /* sdb_strbuf_append */
164 ssize_t
165 sdb_strbuf_vsprintf(sdb_strbuf_t *strbuf, const char *fmt, va_list ap)
166 {
167 if (! strbuf)
168 return -1;
170 if (strbuf->size) {
171 strbuf->string[0] = '\0';
172 strbuf->pos = 0;
173 }
175 return sdb_strbuf_vappend(strbuf, fmt, ap);
176 } /* sdb_strbuf_vsprintf */
178 ssize_t
179 sdb_strbuf_sprintf(sdb_strbuf_t *strbuf, const char *fmt, ...)
180 {
181 va_list ap;
182 ssize_t status;
184 va_start(ap, fmt);
185 status = sdb_strbuf_vsprintf(strbuf, fmt, ap);
186 va_end(ap);
188 return status;
189 } /* sdb_strbuf_sprintf */
191 ssize_t
192 sdb_strbuf_chomp(sdb_strbuf_t *strbuf)
193 {
194 ssize_t ret = 0;
196 if (! strbuf)
197 return -1;
199 assert((!strbuf->size) || (strbuf->pos < strbuf->size));
200 assert(strbuf->pos <= strbuf->size);
202 while ((strbuf->pos > 0)
203 && (strbuf->string[strbuf->pos - 1] == '\n')) {
204 --strbuf->pos;
205 strbuf->string[strbuf->pos] = '\0';
206 ++ret;
207 }
209 return ret;
210 } /* sdb_strbuf_chomp */
212 const char *
213 sdb_strbuf_string(sdb_strbuf_t *strbuf)
214 {
215 if (! strbuf)
216 return NULL;
217 if (! strbuf->size)
218 return "";
219 return strbuf->string;
220 } /* sdb_strbuf_string */
222 size_t
223 sdb_strbuf_len(sdb_strbuf_t *strbuf)
224 {
225 if (! strbuf)
226 return 0;
227 return strbuf->pos;
228 } /* sdb_strbuf_string */
230 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */