git/strbuf.h

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#ifndef STRBUF_H
#define STRBUF_H
/* See Documentation/technical/api-strbuf.txt */
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 (len > (sb->alloc ? sb->alloc - 1 : 0))
die("BUG: strbuf_setlen() beyond buffer");
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 struct strbuf **strbuf_split_buf(const char *, size_t,
int delim, int max);
static inline struct strbuf **strbuf_split_str(const char *str,
int delim, int max)
{
return strbuf_split_buf(str, strlen(str), delim, max);
}
static inline struct strbuf **strbuf_split_max(const struct strbuf *sb,
int delim, int max)
{
return strbuf_split_buf(sb->buf, sb->len, delim, max);
}
static inline struct strbuf **strbuf_split(const struct strbuf *sb, int delim)
{
return strbuf_split_max(sb, delim, 0);
}
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_grow(sb, sb2->len);
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);
struct strbuf_expand_dict_entry {
const char *placeholder;
const char *value;
};
extern size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder, void *context);
extern void strbuf_addbuf_percentquote(struct strbuf *dst, const struct strbuf *src);
--pretty=format: on-demand format expansion Some of the --pretty=format placeholders expansions are expensive to calculate. This is made worse by the current code's use of interpolate(), which requires _all_ placeholders are to be prepared up front. One way to speed this up is to check which placeholders are present in the format string and to prepare only the expansions that are needed. That still leaves the allocation overhead of interpolate(). Another way is to use a callback based approach together with the strbuf library to keep allocations to a minimum and avoid string copies. That's what this patch does. It introduces a new strbuf function, strbuf_expand(). The function takes a format string, list of placeholder strings, a user supplied function 'fn', and an opaque pointer 'context' to tell 'fn' what thingy to operate on. The function 'fn' is expected to accept a strbuf, a parsed placeholder string and the 'context' pointer, and append the interpolated value for the 'context' thingy, according to the format specified by the placeholder. Thanks to Pierre Habouzit for his suggestion to use strchrnul() and the code surrounding its callsite. And thanks to Junio for most of this commit message. :) Here my measurements of most of Paul Mackerras' test cases that highlighted the performance problem (best of three runs): (master) $ time git log --pretty=oneline >/dev/null real 0m0.390s user 0m0.340s sys 0m0.040s (master) $ time git log --pretty=raw >/dev/null real 0m0.434s user 0m0.408s sys 0m0.016s (master) $ time git log --pretty="format:%H {%P} %ct" >/dev/null real 0m1.347s user 0m0.080s sys 0m1.256s (interp_find_active -- Dscho) $ time ./git log --pretty="format:%H {%P} %ct" >/dev/null real 0m0.694s user 0m0.020s sys 0m0.672s (strbuf_expand -- this patch) $ time ./git log --pretty="format:%H {%P} %ct" >/dev/null real 0m0.395s user 0m0.352s sys 0m0.028s Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-11-09 08:49:42 +08:00
__attribute__((format (printf,2,3)))
extern void strbuf_addf(struct strbuf *sb, const char *fmt, ...);
__attribute__((format (printf,2,0)))
extern void strbuf_vaddf(struct strbuf *sb, const char *fmt, va_list ap);
extern void strbuf_add_lines(struct strbuf *sb, const char *prefix, const char *buf, size_t size);
static inline void strbuf_complete_line(struct strbuf *sb)
{
if (sb->len && sb->buf[sb->len - 1] != '\n')
strbuf_addch(sb, '\n');
}
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_readlink(struct strbuf *sb, const char *path, size_t hint);
extern int strbuf_getwholeline(struct strbuf *, FILE *, int);
extern int strbuf_getline(struct strbuf *, FILE *, int);
extern int strbuf_getwholeline_fd(struct strbuf *, int, int);
extern void stripspace(struct strbuf *buf, int skip_comments);
extern int launch_editor(const char *path, struct strbuf *buffer, const char *const *env);
extern int strbuf_branchname(struct strbuf *sb, const char *name);
extern int strbuf_check_branch_ref(struct strbuf *sb, const char *name);
extern void strbuf_add_urlencode(struct strbuf *, const char *, size_t,
int reserved);
extern void strbuf_addstr_urlencode(struct strbuf *, const char *,
int reserved);
#endif /* STRBUF_H */