7 * strbuf's are meant to be used with all the usual C string and memory
8 * APIs. Given that the length of the buffer is known, it's often better to
9 * use the mem* functions than a str* one (memchr vs. strchr e.g.).
10 * Though, one has to be careful about the fact that str* functions often
11 * stop on NULs and that strbufs may have embedded NULs.
13 * A strbuf is NUL terminated for convenience, but no function in the
14 * strbuf API actually relies on the string being free of NULs.
16 * strbufs have some invariants that are very important to keep in mind:
18 * - The `buf` member is never NULL, so it can be used in any usual C
19 * string operations safely. strbuf's _have_ to be initialized either by
20 * `strbuf_init()` or by `= STRBUF_INIT` before the invariants, though.
22 * Do *not* assume anything on what `buf` really is (e.g. if it is
23 * allocated memory or not), use `strbuf_detach()` to unwrap a memory
24 * buffer from its strbuf shell in a safe way. That is the sole supported
25 * way. This will give you a malloced buffer that you can later `free()`.
27 * However, it is totally safe to modify anything in the string pointed by
28 * the `buf` member, between the indices `0` and `len-1` (inclusive).
30 * - The `buf` member is a byte array that has at least `len + 1` bytes
31 * allocated. The extra byte is used to store a `'\0'`, allowing the
32 * `buf` member to be a valid C-string. Every strbuf function ensure this
33 * invariant is preserved.
35 * NOTE: It is OK to "play" with the buffer directly if you work it this
38 * strbuf_grow(sb, SOME_SIZE); <1>
39 * strbuf_setlen(sb, sb->len + SOME_OTHER_SIZE);
41 * <1> Here, the memory array starting at `sb->buf`, and of length
42 * `strbuf_avail(sb)` is all yours, and you can be sure that
43 * `strbuf_avail(sb)` is at least `SOME_SIZE`.
45 * NOTE: `SOME_OTHER_SIZE` must be smaller or equal to `strbuf_avail(sb)`.
47 * Doing so is safe, though if it has to be done in many places, adding the
48 * missing API to the strbuf module is the way to go.
50 * WARNING: Do _not_ assume that the area that is yours is of size `alloc
51 * - 1` even if it's true in the current implementation. Alloc is somehow a
52 * "private" member that should not be messed with. Use `strbuf_avail()`
62 * This is the string buffer structure. The `len` member can be used to
63 * determine the current length of the string, and `buf` member provides
64 * access to the string itself.
72 extern char strbuf_slopbuf
[];
73 #define STRBUF_INIT { .buf = strbuf_slopbuf }
76 * Predeclare this here, since cache.h includes this file before it defines the
82 * Life Cycle Functions
83 * --------------------
87 * Initialize the structure. The second parameter can be zero or a bigger
88 * number to allocate memory, in case you want to prevent further reallocs.
90 void strbuf_init(struct strbuf
*sb
, size_t alloc
);
93 * Release a string buffer and the memory it used. After this call, the
94 * strbuf points to an empty string that does not need to be free()ed, as
95 * if it had been set to `STRBUF_INIT` and never modified.
97 * To clear a strbuf in preparation for further use without the overhead
98 * of free()ing and malloc()ing again, use strbuf_reset() instead.
100 void strbuf_release(struct strbuf
*sb
);
103 * Detach the string from the strbuf and returns it; you now own the
104 * storage the string occupies and it is your responsibility from then on
105 * to release it with `free(3)` when you are done with it.
107 * The strbuf that previously held the string is reset to `STRBUF_INIT` so
108 * it can be reused after calling this function.
110 char *strbuf_detach(struct strbuf
*sb
, size_t *sz
);
113 * Attach a string to a buffer. You should specify the string to attach,
114 * the current length of the string and the amount of allocated memory.
115 * The amount must be larger than the string length, because the string you
116 * pass is supposed to be a NUL-terminated string. This string _must_ be
117 * malloc()ed, and after attaching, the pointer cannot be relied upon
118 * anymore, and neither be free()d directly.
120 void strbuf_attach(struct strbuf
*sb
, void *str
, size_t len
, size_t mem
);
123 * Swap the contents of two string buffers.
125 static inline void strbuf_swap(struct strbuf
*a
, struct strbuf
*b
)
132 * Functions related to the size of the buffer
133 * -------------------------------------------
137 * Determine the amount of allocated but unused memory.
139 static inline size_t strbuf_avail(const struct strbuf
*sb
)
141 return sb
->alloc
? sb
->alloc
- sb
->len
- 1 : 0;
145 * Ensure that at least this amount of unused memory is available after
146 * `len`. This is used when you know a typical size for what you will add
147 * and want to avoid repetitive automatic resizing of the underlying buffer.
148 * This is never a needed operation, but can be critical for performance in
151 void strbuf_grow(struct strbuf
*sb
, size_t amount
);
154 * Set the length of the buffer to a given value. This function does *not*
155 * allocate new memory, so you should not perform a `strbuf_setlen()` to a
156 * length that is larger than `len + strbuf_avail()`. `strbuf_setlen()` is
157 * just meant as a 'please fix invariants from this strbuf I just messed
160 static inline void strbuf_setlen(struct strbuf
*sb
, size_t len
)
162 if (len
> (sb
->alloc
? sb
->alloc
- 1 : 0))
163 BUG("strbuf_setlen() beyond buffer");
165 if (sb
->buf
!= strbuf_slopbuf
)
168 assert(!strbuf_slopbuf
[0]);
172 * Empty the buffer by setting the size of it to zero.
174 #define strbuf_reset(sb) strbuf_setlen(sb, 0)
178 * Functions related to the contents of the buffer
179 * -----------------------------------------------
183 * Strip whitespace from the beginning (`ltrim`), end (`rtrim`), or both side
184 * (`trim`) of a string.
186 void strbuf_trim(struct strbuf
*sb
);
187 void strbuf_rtrim(struct strbuf
*sb
);
188 void strbuf_ltrim(struct strbuf
*sb
);
190 /* Strip trailing directory separators */
191 void strbuf_trim_trailing_dir_sep(struct strbuf
*sb
);
193 /* Strip trailing LF or CR/LF */
194 void strbuf_trim_trailing_newline(struct strbuf
*sb
);
197 * Replace the contents of the strbuf with a reencoded form. Returns -1
198 * on error, 0 on success.
200 int strbuf_reencode(struct strbuf
*sb
, const char *from
, const char *to
);
203 * Lowercase each character in the buffer using `tolower`.
205 void strbuf_tolower(struct strbuf
*sb
);
208 * Compare two buffers. Returns an integer less than, equal to, or greater
209 * than zero if the first buffer is found, respectively, to be less than,
210 * to match, or be greater than the second buffer.
212 int strbuf_cmp(const struct strbuf
*first
, const struct strbuf
*second
);
216 * Adding data to the buffer
217 * -------------------------
219 * NOTE: All of the functions in this section will grow the buffer as
220 * necessary. If they fail for some reason other than memory shortage and the
221 * buffer hadn't been allocated before (i.e. the `struct strbuf` was set to
222 * `STRBUF_INIT`), then they will free() it.
226 * Add a single character to the buffer.
228 static inline void strbuf_addch(struct strbuf
*sb
, int c
)
230 if (!strbuf_avail(sb
))
232 sb
->buf
[sb
->len
++] = c
;
233 sb
->buf
[sb
->len
] = '\0';
237 * Add a character the specified number of times to the buffer.
239 void strbuf_addchars(struct strbuf
*sb
, int c
, size_t n
);
242 * Insert data to the given position of the buffer. The remaining contents
243 * will be shifted, not overwritten.
245 void strbuf_insert(struct strbuf
*sb
, size_t pos
, const void *, size_t);
248 * Insert a NUL-terminated string to the given position of the buffer.
249 * The remaining contents will be shifted, not overwritten. It's an
250 * inline function to allow the compiler to resolve strlen() calls on
251 * constants at compile time.
253 static inline void strbuf_insertstr(struct strbuf
*sb
, size_t pos
,
256 strbuf_insert(sb
, pos
, s
, strlen(s
));
260 * Insert data to the given position of the buffer giving a printf format
261 * string. The contents will be shifted, not overwritten.
263 void strbuf_vinsertf(struct strbuf
*sb
, size_t pos
, const char *fmt
,
266 __attribute__((format (printf
, 3, 4)))
267 void strbuf_insertf(struct strbuf
*sb
, size_t pos
, const char *fmt
, ...);
270 * Remove given amount of data from a given position of the buffer.
272 void strbuf_remove(struct strbuf
*sb
, size_t pos
, size_t len
);
275 * Remove the bytes between `pos..pos+len` and replace it with the given
278 void strbuf_splice(struct strbuf
*sb
, size_t pos
, size_t len
,
279 const void *data
, size_t data_len
);
282 * Add a NUL-terminated string to the buffer. Each line will be prepended
283 * by a comment character and a blank.
285 void strbuf_add_commented_lines(struct strbuf
*out
,
286 const char *buf
, size_t size
);
290 * Add data of given length to the buffer.
292 void strbuf_add(struct strbuf
*sb
, const void *data
, size_t len
);
295 * Add a NUL-terminated string to the buffer.
297 * NOTE: This function will *always* be implemented as an inline or a macro
298 * using strlen, meaning that this is efficient to write things like:
300 * strbuf_addstr(sb, "immediate string");
303 static inline void strbuf_addstr(struct strbuf
*sb
, const char *s
)
305 strbuf_add(sb
, s
, strlen(s
));
309 * Copy the contents of another buffer at the end of the current one.
311 void strbuf_addbuf(struct strbuf
*sb
, const struct strbuf
*sb2
);
314 * Join the arguments into a buffer. `delim` is put between every
317 const char *strbuf_join_argv(struct strbuf
*buf
, int argc
,
318 const char **argv
, char delim
);
321 * Used with `strbuf_expand_step` to expand the literals %n and %x
322 * followed by two hexadecimal digits. Returns the number of recognized
323 * characters. The context argument is ignored.
325 size_t strbuf_expand_literal_cb(struct strbuf
*sb
,
326 const char *placeholder
,
330 * If the string pointed to by `formatp` contains a percent sign ("%"),
331 * advance it to point to the character following the next one and
332 * return 1, otherwise return 0. Append the substring before that
333 * percent sign to `sb`, or the whole string if there is none.
335 int strbuf_expand_step(struct strbuf
*sb
, const char **formatp
);
338 * Append the contents of one strbuf to another, quoting any
339 * percent signs ("%") into double-percents ("%%") in the
340 * destination. This is useful for literal data to be fed to either
341 * strbuf_expand or to the *printf family of functions.
343 void strbuf_addbuf_percentquote(struct strbuf
*dst
, const struct strbuf
*src
);
345 #define STRBUF_ENCODE_SLASH 1
348 * Append the contents of a string to a strbuf, percent-encoding any characters
349 * that are needed to be encoded for a URL.
351 * If STRBUF_ENCODE_SLASH is set in flags, percent-encode slashes. Otherwise,
352 * slashes are not percent-encoded.
354 void strbuf_add_percentencode(struct strbuf
*dst
, const char *src
, int flags
);
357 * Append the given byte size as a human-readable string (i.e. 12.23 KiB,
360 void strbuf_humanise_bytes(struct strbuf
*buf
, off_t bytes
);
363 * Append the given byte rate as a human-readable string (i.e. 12.23 KiB/s,
366 void strbuf_humanise_rate(struct strbuf
*buf
, off_t bytes
);
369 * Add a formatted string to the buffer.
371 __attribute__((format (printf
,2,3)))
372 void strbuf_addf(struct strbuf
*sb
, const char *fmt
, ...);
375 * Add a formatted string prepended by a comment character and a
376 * blank to the buffer.
378 __attribute__((format (printf
, 2, 3)))
379 void strbuf_commented_addf(struct strbuf
*sb
, const char *fmt
, ...);
381 __attribute__((format (printf
,2,0)))
382 void strbuf_vaddf(struct strbuf
*sb
, const char *fmt
, va_list ap
);
385 * Add the time specified by `tm`, as formatted by `strftime`.
386 * `tz_offset` is in decimal hhmm format, e.g. -600 means six hours west
387 * of Greenwich, and it's used to expand %z internally. However, tokens
388 * with modifiers (e.g. %Ez) are passed to `strftime`.
389 * `suppress_tz_name`, when set, expands %Z internally to the empty
390 * string rather than passing it to `strftime`.
392 void strbuf_addftime(struct strbuf
*sb
, const char *fmt
,
393 const struct tm
*tm
, int tz_offset
,
394 int suppress_tz_name
);
397 * Read a given size of data from a FILE* pointer to the buffer.
399 * NOTE: The buffer is rewound if the read fails. If -1 is returned,
400 * `errno` must be consulted, like you would do for `read(3)`.
401 * `strbuf_read()`, `strbuf_read_file()` and `strbuf_getline_*()`
402 * family of functions have the same behaviour as well.
404 size_t strbuf_fread(struct strbuf
*sb
, size_t size
, FILE *file
);
407 * Read the contents of a given file descriptor. The third argument can be
408 * used to give a hint about the file size, to avoid reallocs. If read fails,
409 * any partial read is undone.
411 ssize_t
strbuf_read(struct strbuf
*sb
, int fd
, size_t hint
);
414 * Read the contents of a given file descriptor partially by using only one
415 * attempt of xread. The third argument can be used to give a hint about the
416 * file size, to avoid reallocs. Returns the number of new bytes appended to
419 ssize_t
strbuf_read_once(struct strbuf
*sb
, int fd
, size_t hint
);
422 * Read the contents of a file, specified by its path. The third argument
423 * can be used to give a hint about the file size, to avoid reallocs.
424 * Return the number of bytes read or a negative value if some error
425 * occurred while opening or reading the file.
427 ssize_t
strbuf_read_file(struct strbuf
*sb
, const char *path
, size_t hint
);
430 * Read the target of a symbolic link, specified by its path. The third
431 * argument can be used to give a hint about the size, to avoid reallocs.
433 int strbuf_readlink(struct strbuf
*sb
, const char *path
, size_t hint
);
436 * Write the whole content of the strbuf to the stream not stopping at
439 ssize_t
strbuf_write(struct strbuf
*sb
, FILE *stream
);
442 * Read a line from a FILE *, overwriting the existing contents of
443 * the strbuf. The strbuf_getline*() family of functions share
444 * this signature, but have different line termination conventions.
446 * Reading stops after the terminator or at EOF. The terminator
447 * is removed from the buffer before returning. Returns 0 unless
448 * there was nothing left before EOF, in which case it returns `EOF`.
450 typedef int (*strbuf_getline_fn
)(struct strbuf
*, FILE *);
452 /* Uses LF as the line terminator */
453 int strbuf_getline_lf(struct strbuf
*sb
, FILE *fp
);
455 /* Uses NUL as the line terminator */
456 int strbuf_getline_nul(struct strbuf
*sb
, FILE *fp
);
459 * Similar to strbuf_getline_lf(), but additionally treats a CR that
460 * comes immediately before the LF as part of the terminator.
461 * This is the most friendly version to be used to read "text" files
462 * that can come from platforms whose native text format is CRLF
465 int strbuf_getline(struct strbuf
*sb
, FILE *file
);
469 * Like `strbuf_getline`, but keeps the trailing terminator (if
470 * any) in the buffer.
472 int strbuf_getwholeline(struct strbuf
*sb
, FILE *file
, int term
);
475 * Like `strbuf_getwholeline`, but appends the line instead of
476 * resetting the buffer first.
478 int strbuf_appendwholeline(struct strbuf
*sb
, FILE *file
, int term
);
481 * Like `strbuf_getwholeline`, but operates on a file descriptor.
482 * It reads one character at a time, so it is very slow. Do not
483 * use it unless you need the correct position in the file
486 int strbuf_getwholeline_fd(struct strbuf
*sb
, int fd
, int term
);
489 * Set the buffer to the path of the current working directory.
491 int strbuf_getcwd(struct strbuf
*sb
);
494 * Add a path to a buffer, converting a relative path to an
495 * absolute one in the process. Symbolic links are not
498 void strbuf_add_absolute_path(struct strbuf
*sb
, const char *path
);
501 * Canonize `path` (make it absolute, resolve symlinks, remove extra
502 * slashes) and append it to `sb`. Die with an informative error
503 * message if there is a problem.
505 * The directory part of `path` (i.e., everything up to the last
506 * dir_sep) must denote a valid, existing directory, but the last
507 * component need not exist.
509 * Callers that don't mind links should use the more lightweight
510 * strbuf_add_absolute_path() instead.
512 void strbuf_add_real_path(struct strbuf
*sb
, const char *path
);
516 * Normalize in-place the path contained in the strbuf. See
517 * normalize_path_copy() for details. If an error occurs, the contents of "sb"
518 * are left untouched, and -1 is returned.
520 int strbuf_normalize_path(struct strbuf
*sb
);
523 * Strip whitespace from a buffer. The second parameter controls if
524 * comments are considered contents to be removed or not.
526 void strbuf_stripspace(struct strbuf
*buf
, int skip_comments
);
528 static inline int strbuf_strip_suffix(struct strbuf
*sb
, const char *suffix
)
530 if (strip_suffix_mem(sb
->buf
, &sb
->len
, suffix
)) {
531 strbuf_setlen(sb
, sb
->len
);
538 * Split str (of length slen) at the specified terminator character.
539 * Return a null-terminated array of pointers to strbuf objects
540 * holding the substrings. The substrings include the terminator,
541 * except for the last substring, which might be unterminated if the
542 * original string did not end with a terminator. If max is positive,
543 * then split the string into at most max substrings (with the last
544 * substring containing everything following the (max-1)th terminator
547 * The most generic form is `strbuf_split_buf`, which takes an arbitrary
548 * pointer/len buffer. The `_str` variant takes a NUL-terminated string,
549 * the `_max` variant takes a strbuf, and just `strbuf_split` is a convenience
550 * wrapper to drop the `max` parameter.
552 * For lighter-weight alternatives, see string_list_split() and
553 * string_list_split_in_place().
555 struct strbuf
**strbuf_split_buf(const char *str
, size_t len
,
556 int terminator
, int max
);
558 static inline struct strbuf
**strbuf_split_str(const char *str
,
559 int terminator
, int max
)
561 return strbuf_split_buf(str
, strlen(str
), terminator
, max
);
564 static inline struct strbuf
**strbuf_split_max(const struct strbuf
*sb
,
565 int terminator
, int max
)
567 return strbuf_split_buf(sb
->buf
, sb
->len
, terminator
, max
);
570 static inline struct strbuf
**strbuf_split(const struct strbuf
*sb
,
573 return strbuf_split_max(sb
, terminator
, 0);
577 * Adds all strings of a string list to the strbuf, separated by the given
578 * separator. For example, if sep is
581 * ['element1', 'element2', ..., 'elementN'],
583 * 'element1, element2, ..., elementN'
584 * to str. If only one element, just write "element1" to str.
586 void strbuf_add_separated_string_list(struct strbuf
*str
,
588 struct string_list
*slist
);
591 * Free a NULL-terminated list of strbufs (for example, the return
592 * values of the strbuf_split*() functions).
594 void strbuf_list_free(struct strbuf
**list
);
597 * Add the abbreviation, as generated by repo_find_unique_abbrev(), of `sha1` to
601 void strbuf_repo_add_unique_abbrev(struct strbuf
*sb
, struct repository
*repo
,
602 const struct object_id
*oid
, int abbrev_len
);
603 void strbuf_add_unique_abbrev(struct strbuf
*sb
, const struct object_id
*oid
,
607 * Remove the filename from the provided path string. If the path
608 * contains a trailing separator, then the path is considered a directory
609 * and nothing is modified.
612 * - "/path/to/file" -> "/path/to/"
613 * - "/path/to/dir/" -> "/path/to/dir/"
615 void strbuf_strip_file_from_path(struct strbuf
*sb
);
617 void strbuf_add_lines(struct strbuf
*sb
,
623 * Append s to sb, with the characters '<', '>', '&' and '"' converted
626 void strbuf_addstr_xml_quoted(struct strbuf
*sb
,
630 * "Complete" the contents of `sb` by ensuring that either it ends with the
631 * character `term`, or it is empty. This can be used, for example,
632 * to ensure that text ends with a newline, but without creating an empty
633 * blank line if there is no content in the first place.
635 static inline void strbuf_complete(struct strbuf
*sb
, char term
)
637 if (sb
->len
&& sb
->buf
[sb
->len
- 1] != term
)
638 strbuf_addch(sb
, term
);
641 static inline void strbuf_complete_line(struct strbuf
*sb
)
643 strbuf_complete(sb
, '\n');
647 * Copy "name" to "sb", expanding any special @-marks as handled by
648 * repo_interpret_branch_name(). The result is a non-qualified branch name
649 * (so "foo" or "origin/master" instead of "refs/heads/foo" or
650 * "refs/remotes/origin/master").
652 * Note that the resulting name may not be a syntactically valid refname.
654 * If "allowed" is non-zero, restrict the set of allowed expansions. See
655 * repo_interpret_branch_name() for details.
657 void strbuf_branchname(struct strbuf
*sb
, const char *name
,
661 * Like strbuf_branchname() above, but confirm that the result is
662 * syntactically valid to be used as a local branch name in refs/heads/.
664 * The return value is "0" if the result is valid, and "-1" otherwise.
666 int strbuf_check_branch_ref(struct strbuf
*sb
, const char *name
);
668 typedef int (*char_predicate
)(char ch
);
670 int is_rfc3986_unreserved(char ch
);
671 int is_rfc3986_reserved_or_unreserved(char ch
);
673 void strbuf_addstr_urlencode(struct strbuf
*sb
, const char *name
,
674 char_predicate allow_unencoded_fn
);
676 __attribute__((format (printf
,1,2)))
677 int printf_ln(const char *fmt
, ...);
678 __attribute__((format (printf
,2,3)))
679 int fprintf_ln(FILE *fp
, const char *fmt
, ...);
681 char *xstrdup_tolower(const char *);
682 char *xstrdup_toupper(const char *);
685 * Create a newly allocated string using printf format. You can do this easily
686 * with a strbuf, but this provides a shortcut to save a few lines.
688 __attribute__((format (printf
, 1, 0)))
689 char *xstrvfmt(const char *fmt
, va_list ap
);
690 __attribute__((format (printf
, 1, 2)))
691 char *xstrfmt(const char *fmt
, ...);
693 #endif /* STRBUF_H */