1 /*
2 * libJUNOS - src/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 /*
29 * String buffer object.
30 */
32 #include "junos.h"
34 #include <assert.h>
36 #include <stdio.h>
37 #include <stdlib.h>
38 #include <stdarg.h>
40 /*
41 * private data structures
42 */
44 struct junos_strbuf {
45 char *string;
46 size_t size;
47 size_t pos;
48 };
50 /*
51 * private helper functions
52 */
54 static int
55 strbuf_resize(junos_strbuf_t *strbuf)
56 {
57 char *tmp;
59 tmp = realloc(strbuf->string, 2 * strbuf->size);
60 if (! tmp)
61 return -1;
63 strbuf->string = tmp;
64 strbuf->size *= 2;
66 strbuf->string[strbuf->pos] = '\0';
67 return 0;
68 } /* strbuf_resize */
70 /*
71 * public API
72 */
74 junos_strbuf_t *
75 junos_strbuf_new(size_t size)
76 {
77 junos_strbuf_t *strbuf;
79 strbuf = calloc(1, sizeof(*strbuf));
80 if (! strbuf)
81 return NULL;
83 if (! size)
84 return strbuf;
86 strbuf->string = malloc(size);
87 if (strbuf->string) {
88 strbuf->string[0] = '\0';
89 strbuf->size = size;
90 }
92 return strbuf;
93 } /* junos_strbuf_new */
95 void
96 junos_strbuf_free(junos_strbuf_t *strbuf)
97 {
98 if (! strbuf)
99 return;
101 free(strbuf->string);
102 free(strbuf);
103 } /* junos_strbuf_free */
105 ssize_t
106 junos_strbuf_vsprintf(junos_strbuf_t *strbuf, const char *fmt, va_list ap)
107 {
108 int status;
110 if (! strbuf)
111 return -1;
113 assert(strbuf->string[strbuf->pos] == '\0');
115 if (strbuf->pos >= strbuf->size)
116 if (strbuf_resize(strbuf))
117 return -1;
119 status = vsnprintf(strbuf->string + strbuf->pos,
120 strbuf->size - strbuf->pos, fmt, ap);
122 if (status < 0)
123 return status;
125 if ((size_t)status >= strbuf->size - strbuf->pos) {
126 strbuf_resize(strbuf);
127 return junos_strbuf_vsprintf(strbuf, fmt, ap);
128 }
130 strbuf->pos += (size_t)status;
131 return (ssize_t)strbuf->pos;
132 } /* junos_strbuf_vsprintf */
134 ssize_t
135 junos_strbuf_sprintf(junos_strbuf_t *strbuf, const char *fmt, ...)
136 {
137 va_list ap;
138 ssize_t status;
140 va_start(ap, fmt);
141 status = junos_strbuf_vsprintf(strbuf, fmt, ap);
142 va_end(ap);
144 return status;
145 } /* junos_strbuf_sprintf */
147 char *
148 junos_strbuf_string(junos_strbuf_t *strbuf)
149 {
150 if (! strbuf)
151 return NULL;
152 return strbuf->string;
153 } /* junos_strbuf_string */
155 size_t
156 junos_strbuf_len(junos_strbuf_t *strbuf)
157 {
158 if (! strbuf)
159 return 0;
160 return strbuf->pos;
161 } /* junos_strbuf_string */
163 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */