xref: /redis-3.2.3/deps/lua/src/strbuf.h (revision 44acd50a)
1 /* strbuf - String buffer routines
2  *
3  * Copyright (c) 2010-2011  Mark Pulford <[email protected]>
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining
6  * a copy of this software and associated documentation files (the
7  * "Software"), to deal in the Software without restriction, including
8  * without limitation the rights to use, copy, modify, merge, publish,
9  * distribute, sublicense, and/or sell copies of the Software, and to
10  * permit persons to whom the Software is furnished to do so, subject to
11  * the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be
14  * included in all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
17  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
18  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
19  * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
20  * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
21  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
22  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
23  */
24 
25 #include <stdlib.h>
26 #include <stdarg.h>
27 
28 /* Size: Total bytes allocated to *buf
29  * Length: String length, excluding optional NULL terminator.
30  * Increment: Allocation increments when resizing the string buffer.
31  * Dynamic: True if created via strbuf_new()
32  */
33 
34 typedef struct {
35     char *buf;
36     int size;
37     int length;
38     int increment;
39     int dynamic;
40     int reallocs;
41     int debug;
42 } strbuf_t;
43 
44 #ifndef STRBUF_DEFAULT_SIZE
45 #define STRBUF_DEFAULT_SIZE 1023
46 #endif
47 #ifndef STRBUF_DEFAULT_INCREMENT
48 #define STRBUF_DEFAULT_INCREMENT -2
49 #endif
50 
51 /* Initialise */
52 extern strbuf_t *strbuf_new(int len);
53 extern void strbuf_init(strbuf_t *s, int len);
54 extern void strbuf_set_increment(strbuf_t *s, int increment);
55 
56 /* Release */
57 extern void strbuf_free(strbuf_t *s);
58 extern char *strbuf_free_to_string(strbuf_t *s, int *len);
59 
60 /* Management */
61 extern void strbuf_resize(strbuf_t *s, int len);
62 static int strbuf_empty_length(strbuf_t *s);
63 static int strbuf_length(strbuf_t *s);
64 static char *strbuf_string(strbuf_t *s, int *len);
65 static  void strbuf_ensure_empty_length(strbuf_t *s, int len);
66 
67 /* Update */
68 extern void strbuf_append_fmt(strbuf_t *s, int len, const char *fmt, ...);
69 extern void strbuf_append_fmt_retry(strbuf_t *s, const char *format, ...);
70 static void strbuf_append_mem(strbuf_t *s, const char *c, int len);
71 extern void strbuf_append_string(strbuf_t *s, const char *str);
72 static void strbuf_append_char(strbuf_t *s, const char c);
73 static void strbuf_ensure_null(strbuf_t *s);
74 
75 /* Reset string for before use */
76 static inline void strbuf_reset(strbuf_t *s)
77 {
78     s->length = 0;
79 }
80 
81 static inline int strbuf_allocated(strbuf_t *s)
82 {
83     return s->buf != NULL;
84 }
85 
86 /* Return bytes remaining in the string buffer
87  * Ensure there is space for a NULL terminator. */
88 static inline int strbuf_empty_length(strbuf_t *s)
89 {
90     return s->size - s->length - 1;
91 }
92 
93 static inline void strbuf_ensure_empty_length(strbuf_t *s, int len)
94 {
95     if (len > strbuf_empty_length(s))
96         strbuf_resize(s, s->length + len);
97 }
98 
99 static inline int strbuf_length(strbuf_t *s)
100 {
101     return s->length;
102 }
103 
104 static inline void strbuf_append_char(strbuf_t *s, const char c)
105 {
106     strbuf_ensure_empty_length(s, 1);
107     s->buf[s->length++] = c;
108 }
109 
110 static inline void strbuf_append_char_unsafe(strbuf_t *s, const char c)
111 {
112     s->buf[s->length++] = c;
113 }
114 
115 static inline void strbuf_append_mem(strbuf_t *s, const char *c, int len)
116 {
117     strbuf_ensure_empty_length(s, len);
118     memcpy(s->buf + s->length, c, len);
119     s->length += len;
120 }
121 
122 static inline void strbuf_append_mem_unsafe(strbuf_t *s, const char *c, int len)
123 {
124     memcpy(s->buf + s->length, c, len);
125     s->length += len;
126 }
127 
128 static inline void strbuf_ensure_null(strbuf_t *s)
129 {
130     s->buf[s->length] = 0;
131 }
132 
133 static inline char *strbuf_string(strbuf_t *s, int *len)
134 {
135     if (len)
136         *len = s->length;
137 
138     return s->buf;
139 }
140 
141 /* vi:ai et sw=4 ts=4:
142  */
143