gitweb: Add git_merge sub
[git/gsoc2010-gitweb.git] / strbuf.h
blobfac2dbc24fc654e58840727204043a198d065921
1 #ifndef STRBUF_H
2 #define STRBUF_H
4 /*
5 * Strbuf's can be use in many ways: as a byte array, or to store arbitrary
6 * long, overflow safe strings.
8 * Strbufs has some invariants that are very important to keep in mind:
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.
13 * It is NOT legal to copy the ->buf pointer away.
14 * `strbuf_detach' is the operation that detaches a buffer from its shell
15 * while keeping the shell valid wrt its invariants.
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.
22 * Note that it is OK to "play" with the buffer directly if you work it
23 * that way:
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);
31 * Of course, SOME_OTHER_SIZE must be smaller or equal to strbuf_avail(sb).
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.
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.
41 #include <assert.h>
43 extern char strbuf_slopbuf[];
44 struct strbuf {
45 size_t alloc;
46 size_t len;
47 char *buf;
50 #define STRBUF_INIT { 0, 0, strbuf_slopbuf }
52 /*----- strbuf life cycle -----*/
53 extern void strbuf_init(struct strbuf *, size_t);
54 extern void strbuf_release(struct strbuf *);
55 extern char *strbuf_detach(struct strbuf *, size_t *);
56 extern void strbuf_attach(struct strbuf *, void *, size_t, size_t);
57 static inline void strbuf_swap(struct strbuf *a, struct strbuf *b) {
58 struct strbuf tmp = *a;
59 *a = *b;
60 *b = tmp;
63 /*----- strbuf size related -----*/
64 static inline size_t strbuf_avail(const struct strbuf *sb) {
65 return sb->alloc ? sb->alloc - sb->len - 1 : 0;
68 extern void strbuf_grow(struct strbuf *, size_t);
70 static 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';
77 #define strbuf_reset(sb) strbuf_setlen(sb, 0)
79 /*----- content related -----*/
80 extern void strbuf_trim(struct strbuf *);
81 extern void strbuf_rtrim(struct strbuf *);
82 extern void strbuf_ltrim(struct strbuf *);
83 extern int strbuf_cmp(const struct strbuf *, const struct strbuf *);
85 extern struct strbuf **strbuf_split(const struct strbuf *, int delim);
86 extern void strbuf_list_free(struct strbuf **);
88 /*----- add data in your buffer -----*/
89 static inline void strbuf_addch(struct strbuf *sb, int c) {
90 strbuf_grow(sb, 1);
91 sb->buf[sb->len++] = c;
92 sb->buf[sb->len] = '\0';
95 extern void strbuf_insert(struct strbuf *, size_t pos, const void *, size_t);
96 extern void strbuf_remove(struct strbuf *, size_t pos, size_t len);
98 /* splice pos..pos+len with given data */
99 extern void strbuf_splice(struct strbuf *, size_t pos, size_t len,
100 const void *, size_t);
102 extern void strbuf_add(struct strbuf *, const void *, size_t);
103 static inline void strbuf_addstr(struct strbuf *sb, const char *s) {
104 strbuf_add(sb, s, strlen(s));
106 static inline void strbuf_addbuf(struct strbuf *sb, const struct strbuf *sb2) {
107 strbuf_grow(sb, sb2->len);
108 strbuf_add(sb, sb2->buf, sb2->len);
110 extern void strbuf_adddup(struct strbuf *sb, size_t pos, size_t len);
112 typedef size_t (*expand_fn_t) (struct strbuf *sb, const char *placeholder, void *context);
113 extern void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn, void *context);
114 struct strbuf_expand_dict_entry {
115 const char *placeholder;
116 const char *value;
118 extern size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder, void *context);
119 extern void strbuf_addbuf_percentquote(struct strbuf *dst, const struct strbuf *src);
121 __attribute__((format (printf,2,3)))
122 extern void strbuf_addf(struct strbuf *sb, const char *fmt, ...);
124 extern size_t strbuf_fread(struct strbuf *, size_t, FILE *);
125 /* XXX: if read fails, any partial read is undone */
126 extern ssize_t strbuf_read(struct strbuf *, int fd, size_t hint);
127 extern int strbuf_read_file(struct strbuf *sb, const char *path, size_t hint);
128 extern int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint);
130 extern int strbuf_getwholeline(struct strbuf *, FILE *, int);
131 extern int strbuf_getline(struct strbuf *, FILE *, int);
133 extern void stripspace(struct strbuf *buf, int skip_comments);
134 extern int launch_editor(const char *path, struct strbuf *buffer, const char *const *env);
136 extern int strbuf_branchname(struct strbuf *sb, const char *name);
137 extern int strbuf_check_branch_ref(struct strbuf *sb, const char *name);
139 #endif /* STRBUF_H */