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Ingo Molnar07800602009-04-20 15:00:56 +02001#ifndef STRBUF_H
2#define STRBUF_H
3
4/*
5 * Strbuf's can be use in many ways: as a byte array, or to store arbitrary
6 * long, overflow safe strings.
7 *
8 * Strbufs has some invariants that are very important to keep in mind:
9 *
10 * 1. the ->buf member is always malloc-ed, hence strbuf's can be used to
11 * build complex strings/buffers whose final size isn't easily known.
12 *
13 * It is NOT legal to copy the ->buf pointer away.
14 * `strbuf_detach' is the operation that detachs a buffer from its shell
15 * while keeping the shell valid wrt its invariants.
16 *
17 * 2. the ->buf member is a byte array that has at least ->len + 1 bytes
18 * allocated. The extra byte is used to store a '\0', allowing the ->buf
19 * member to be a valid C-string. Every strbuf function ensure this
20 * invariant is preserved.
21 *
22 * Note that it is OK to "play" with the buffer directly if you work it
23 * that way:
24 *
25 * strbuf_grow(sb, SOME_SIZE);
26 * ... Here, the memory array starting at sb->buf, and of length
27 * ... strbuf_avail(sb) is all yours, and you are sure that
28 * ... strbuf_avail(sb) is at least SOME_SIZE.
29 * strbuf_setlen(sb, sb->len + SOME_OTHER_SIZE);
30 *
31 * Of course, SOME_OTHER_SIZE must be smaller or equal to strbuf_avail(sb).
32 *
33 * Doing so is safe, though if it has to be done in many places, adding the
34 * missing API to the strbuf module is the way to go.
35 *
36 * XXX: do _not_ assume that the area that is yours is of size ->alloc - 1
37 * even if it's true in the current implementation. Alloc is somehow a
38 * "private" member that should not be messed with.
39 */
40
41#include <assert.h>
42
43extern char strbuf_slopbuf[];
44struct strbuf {
45 size_t alloc;
46 size_t len;
47 char *buf;
48};
49
50#define STRBUF_INIT { 0, 0, strbuf_slopbuf }
51
52/*----- strbuf life cycle -----*/
53extern void strbuf_init(struct strbuf *, size_t);
54extern void strbuf_release(struct strbuf *);
55extern char *strbuf_detach(struct strbuf *, size_t *);
56extern void strbuf_attach(struct strbuf *, void *, size_t, size_t);
57static inline void strbuf_swap(struct strbuf *a, struct strbuf *b) {
58 struct strbuf tmp = *a;
59 *a = *b;
60 *b = tmp;
61}
62
63/*----- strbuf size related -----*/
64static inline size_t strbuf_avail(const struct strbuf *sb) {
65 return sb->alloc ? sb->alloc - sb->len - 1 : 0;
66}
67
68extern void strbuf_grow(struct strbuf *, size_t);
69
70static inline void strbuf_setlen(struct strbuf *sb, size_t len) {
71 if (!sb->alloc)
72 strbuf_grow(sb, 0);
73 assert(len < sb->alloc);
74 sb->len = len;
75 sb->buf[len] = '\0';
76}
77#define strbuf_reset(sb) strbuf_setlen(sb, 0)
78
79/*----- content related -----*/
80extern void strbuf_trim(struct strbuf *);
81extern void strbuf_rtrim(struct strbuf *);
82extern void strbuf_ltrim(struct strbuf *);
83extern int strbuf_cmp(const struct strbuf *, const struct strbuf *);
84extern void strbuf_tolower(struct strbuf *);
85
86extern struct strbuf **strbuf_split(const struct strbuf *, int delim);
87extern void strbuf_list_free(struct strbuf **);
88
89/*----- add data in your buffer -----*/
90static inline void strbuf_addch(struct strbuf *sb, int c) {
91 strbuf_grow(sb, 1);
92 sb->buf[sb->len++] = c;
93 sb->buf[sb->len] = '\0';
94}
95
96extern void strbuf_insert(struct strbuf *, size_t pos, const void *, size_t);
97extern void strbuf_remove(struct strbuf *, size_t pos, size_t len);
98
99/* splice pos..pos+len with given data */
100extern void strbuf_splice(struct strbuf *, size_t pos, size_t len,
101 const void *, size_t);
102
103extern void strbuf_add(struct strbuf *, const void *, size_t);
104static inline void strbuf_addstr(struct strbuf *sb, const char *s) {
105 strbuf_add(sb, s, strlen(s));
106}
107static inline void strbuf_addbuf(struct strbuf *sb, const struct strbuf *sb2) {
108 strbuf_add(sb, sb2->buf, sb2->len);
109}
110extern void strbuf_adddup(struct strbuf *sb, size_t pos, size_t len);
111
112typedef size_t (*expand_fn_t) (struct strbuf *sb, const char *placeholder, void *context);
113extern void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn, void *context);
114struct strbuf_expand_dict_entry {
115 const char *placeholder;
116 const char *value;
117};
118extern size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder, void *context);
119
120__attribute__((format(printf,2,3)))
121extern void strbuf_addf(struct strbuf *sb, const char *fmt, ...);
122
123extern size_t strbuf_fread(struct strbuf *, size_t, FILE *);
124/* XXX: if read fails, any partial read is undone */
125extern ssize_t strbuf_read(struct strbuf *, int fd, size_t hint);
126extern int strbuf_read_file(struct strbuf *sb, const char *path, size_t hint);
127extern int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint);
128
129extern int strbuf_getline(struct strbuf *, FILE *, int);
130
131extern void stripspace(struct strbuf *buf, int skip_comments);
132extern int launch_editor(const char *path, struct strbuf *buffer, const char *const *env);
133
134extern int strbuf_branchname(struct strbuf *sb, const char *name);
135extern int strbuf_check_branch_ref(struct strbuf *sb, const char *name);
136
137#endif /* STRBUF_H */