git/strbuf.h
Stephan Beyer 7198203ae3 editor.c: Libify launch_editor()
This patch removes exit()/die() calls and builtin-specific messages
from launch_editor(), so that it can be used as a general libgit.a
function to launch an editor.

Signed-off-by: Stephan Beyer <s-beyer@gmx.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-07-25 17:09:38 -07:00

129 lines
4.5 KiB
C

#ifndef STRBUF_H
#define STRBUF_H
/*
* Strbuf's can be use in many ways: as a byte array, or to store arbitrary
* long, overflow safe strings.
*
* Strbufs has some invariants that are very important to keep in mind:
*
* 1. the ->buf member is always malloc-ed, hence strbuf's can be used to
* build complex strings/buffers whose final size isn't easily known.
*
* It is NOT legal to copy the ->buf pointer away.
* `strbuf_detach' is the operation that detachs a buffer from its shell
* while keeping the shell valid wrt its invariants.
*
* 2. the ->buf member is a byte array that has at least ->len + 1 bytes
* allocated. The extra byte is used to store a '\0', allowing the ->buf
* member to be a valid C-string. Every strbuf function ensure this
* invariant is preserved.
*
* Note that it is OK to "play" with the buffer directly if you work it
* that way:
*
* strbuf_grow(sb, SOME_SIZE);
* ... Here, the memory array starting at sb->buf, and of length
* ... strbuf_avail(sb) is all yours, and you are sure that
* ... strbuf_avail(sb) is at least SOME_SIZE.
* strbuf_setlen(sb, sb->len + SOME_OTHER_SIZE);
*
* Of course, SOME_OTHER_SIZE must be smaller or equal to strbuf_avail(sb).
*
* Doing so is safe, though if it has to be done in many places, adding the
* missing API to the strbuf module is the way to go.
*
* XXX: do _not_ assume that the area that is yours is of size ->alloc - 1
* even if it's true in the current implementation. Alloc is somehow a
* "private" member that should not be messed with.
*/
#include <assert.h>
extern char strbuf_slopbuf[];
struct strbuf {
size_t alloc;
size_t len;
char *buf;
};
#define STRBUF_INIT { 0, 0, strbuf_slopbuf }
/*----- strbuf life cycle -----*/
extern void strbuf_init(struct strbuf *, size_t);
extern void strbuf_release(struct strbuf *);
extern char *strbuf_detach(struct strbuf *, size_t *);
extern void strbuf_attach(struct strbuf *, void *, size_t, size_t);
static inline void strbuf_swap(struct strbuf *a, struct strbuf *b) {
struct strbuf tmp = *a;
*a = *b;
*b = tmp;
}
/*----- strbuf size related -----*/
static inline size_t strbuf_avail(const struct strbuf *sb) {
return sb->alloc ? sb->alloc - sb->len - 1 : 0;
}
extern void strbuf_grow(struct strbuf *, size_t);
static inline void strbuf_setlen(struct strbuf *sb, size_t len) {
if (!sb->alloc)
strbuf_grow(sb, 0);
assert(len < sb->alloc);
sb->len = len;
sb->buf[len] = '\0';
}
#define strbuf_reset(sb) strbuf_setlen(sb, 0)
/*----- content related -----*/
extern void strbuf_trim(struct strbuf *);
extern void strbuf_rtrim(struct strbuf *);
extern void strbuf_ltrim(struct strbuf *);
extern int strbuf_cmp(const struct strbuf *, const struct strbuf *);
extern void strbuf_tolower(struct strbuf *);
extern struct strbuf **strbuf_split(const struct strbuf *, int delim);
extern void strbuf_list_free(struct strbuf **);
/*----- add data in your buffer -----*/
static inline void strbuf_addch(struct strbuf *sb, int c) {
strbuf_grow(sb, 1);
sb->buf[sb->len++] = c;
sb->buf[sb->len] = '\0';
}
extern void strbuf_insert(struct strbuf *, size_t pos, const void *, size_t);
extern void strbuf_remove(struct strbuf *, size_t pos, size_t len);
/* splice pos..pos+len with given data */
extern void strbuf_splice(struct strbuf *, size_t pos, size_t len,
const void *, size_t);
extern void strbuf_add(struct strbuf *, const void *, size_t);
static inline void strbuf_addstr(struct strbuf *sb, const char *s) {
strbuf_add(sb, s, strlen(s));
}
static inline void strbuf_addbuf(struct strbuf *sb, const struct strbuf *sb2) {
strbuf_add(sb, sb2->buf, sb2->len);
}
extern void strbuf_adddup(struct strbuf *sb, size_t pos, size_t len);
typedef size_t (*expand_fn_t) (struct strbuf *sb, const char *placeholder, void *context);
extern void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn, void *context);
__attribute__((format(printf,2,3)))
extern void strbuf_addf(struct strbuf *sb, const char *fmt, ...);
extern size_t strbuf_fread(struct strbuf *, size_t, FILE *);
/* XXX: if read fails, any partial read is undone */
extern ssize_t strbuf_read(struct strbuf *, int fd, size_t hint);
extern int strbuf_read_file(struct strbuf *sb, const char *path, size_t hint);
extern int strbuf_getline(struct strbuf *, FILE *, int);
extern void stripspace(struct strbuf *buf, int skip_comments);
extern int launch_editor(const char *path, struct strbuf *buffer, const char *const *env);
#endif /* STRBUF_H */