merge(third_party/git): Merge squashed git subtree at v2.23.0 r/373

Merge commit '1b593e1ea4d2af0f6444d9a7788d5d99abd6fde5' as 'third_party/git'

1 files changed, 695 insertions, 0 deletions

diff --git a/third_party/git/strbuf.h b/third_party/git/strbuf.h
new file mode 100644
index 000000000000..f62278a0be59
--- /dev/null
+++ b/third_party/git/strbuf.h
@@ -0,0 +1,695 @@
+#ifndef STRBUF_H
+#define STRBUF_H
+
+struct string_list;
+
+/**
+ * strbuf's are meant to be used with all the usual C string and memory
+ * APIs. Given that the length of the buffer is known, it's often better to
+ * use the mem* functions than a str* one (memchr vs. strchr e.g.).
+ * Though, one has to be careful about the fact that str* functions often
+ * stop on NULs and that strbufs may have embedded NULs.
+ *
+ * A strbuf is NUL terminated for convenience, but no function in the
+ * strbuf API actually relies on the string being free of NULs.
+ *
+ * strbufs have some invariants that are very important to keep in mind:
+ *
+ *  - The `buf` member is never NULL, so it can be used in any usual C
+ *    string operations safely. strbuf's _have_ to be initialized either by
+ *    `strbuf_init()` or by `= STRBUF_INIT` before the invariants, though.
+ *
+ *    Do *not* assume anything on what `buf` really is (e.g. if it is
+ *    allocated memory or not), use `strbuf_detach()` to unwrap a memory
+ *    buffer from its strbuf shell in a safe way. That is the sole supported
+ *    way. This will give you a malloced buffer that you can later `free()`.
+ *
+ *    However, it is totally safe to modify anything in the string pointed by
+ *    the `buf` member, between the indices `0` and `len-1` (inclusive).
+ *
+ *  - 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: It is OK to "play" with the buffer directly if you work it this
+ *    way:
+ *
+ *        strbuf_grow(sb, SOME_SIZE); <1>
+ *        strbuf_setlen(sb, sb->len + SOME_OTHER_SIZE);
+ *
+ *    <1> Here, the memory array starting at `sb->buf`, and of length
+ *    `strbuf_avail(sb)` is all yours, and you can be sure that
+ *    `strbuf_avail(sb)` is at least `SOME_SIZE`.
+ *
+ *    NOTE: `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.
+ *
+ *    WARNING: 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. Use `strbuf_avail()`
+ *    instead.
+*/
+
+/**
+ * Data Structures
+ * ---------------
+ */
+
+/**
+ * This is the string buffer structure. The `len` member can be used to
+ * determine the current length of the string, and `buf` member provides
+ * access to the string itself.
+ */
+struct strbuf {
+	size_t alloc;
+	size_t len;
+	char *buf;
+};
+
+extern char strbuf_slopbuf[];
+#define STRBUF_INIT  { .alloc = 0, .len = 0, .buf = strbuf_slopbuf }
+
+/*
+ * Predeclare this here, since cache.h includes this file before it defines the
+ * struct.
+ */
+struct object_id;
+
+/**
+ * Life Cycle Functions
+ * --------------------
+ */
+
+/**
+ * Initialize the structure. The second parameter can be zero or a bigger
+ * number to allocate memory, in case you want to prevent further reallocs.
+ */
+void strbuf_init(struct strbuf *sb, size_t alloc);
+
+/**
+ * Release a string buffer and the memory it used. After this call, the
+ * strbuf points to an empty string that does not need to be free()ed, as
+ * if it had been set to `STRBUF_INIT` and never modified.
+ *
+ * To clear a strbuf in preparation for further use without the overhead
+ * of free()ing and malloc()ing again, use strbuf_reset() instead.
+ */
+void strbuf_release(struct strbuf *sb);
+
+/**
+ * Detach the string from the strbuf and returns it; you now own the
+ * storage the string occupies and it is your responsibility from then on
+ * to release it with `free(3)` when you are done with it.
+ *
+ * The strbuf that previously held the string is reset to `STRBUF_INIT` so
+ * it can be reused after calling this function.
+ */
+char *strbuf_detach(struct strbuf *sb, size_t *sz);
+
+/**
+ * Attach a string to a buffer. You should specify the string to attach,
+ * the current length of the string and the amount of allocated memory.
+ * The amount must be larger than the string length, because the string you
+ * pass is supposed to be a NUL-terminated string.  This string _must_ be
+ * malloc()ed, and after attaching, the pointer cannot be relied upon
+ * anymore, and neither be free()d directly.
+ */
+void strbuf_attach(struct strbuf *sb, void *str, size_t len, size_t mem);
+
+/**
+ * Swap the contents of two string buffers.
+ */
+static inline void strbuf_swap(struct strbuf *a, struct strbuf *b)
+{
+	SWAP(*a, *b);
+}
+
+
+/**
+ * Functions related to the size of the buffer
+ * -------------------------------------------
+ */
+
+/**
+ * Determine the amount of allocated but unused memory.
+ */
+static inline size_t strbuf_avail(const struct strbuf *sb)
+{
+	return sb->alloc ? sb->alloc - sb->len - 1 : 0;
+}
+
+/**
+ * Ensure that at least this amount of unused memory is available after
+ * `len`. This is used when you know a typical size for what you will add
+ * and want to avoid repetitive automatic resizing of the underlying buffer.
+ * This is never a needed operation, but can be critical for performance in
+ * some cases.
+ */
+void strbuf_grow(struct strbuf *sb, size_t amount);
+
+/**
+ * Set the length of the buffer to a given value. This function does *not*
+ * allocate new memory, so you should not perform a `strbuf_setlen()` to a
+ * length that is larger than `len + strbuf_avail()`. `strbuf_setlen()` is
+ * just meant as a 'please fix invariants from this strbuf I just messed
+ * with'.
+ */
+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;
+	if (sb->buf != strbuf_slopbuf)
+		sb->buf[len] = '\0';
+	else
+		assert(!strbuf_slopbuf[0]);
+}
+
+/**
+ * Empty the buffer by setting the size of it to zero.
+ */
+#define strbuf_reset(sb)  strbuf_setlen(sb, 0)
+
+
+/**
+ * Functions related to the contents of the buffer
+ * -----------------------------------------------
+ */
+
+/**
+ * Strip whitespace from the beginning (`ltrim`), end (`rtrim`), or both side
+ * (`trim`) of a string.
+ */
+void strbuf_trim(struct strbuf *sb);
+void strbuf_rtrim(struct strbuf *sb);
+void strbuf_ltrim(struct strbuf *sb);
+
+/* Strip trailing directory separators */
+void strbuf_trim_trailing_dir_sep(struct strbuf *sb);
+
+/* Strip trailing LF or CR/LF */
+void strbuf_trim_trailing_newline(struct strbuf *sb);
+
+/**
+ * Replace the contents of the strbuf with a reencoded form.  Returns -1
+ * on error, 0 on success.
+ */
+int strbuf_reencode(struct strbuf *sb, const char *from, const char *to);
+
+/**
+ * Lowercase each character in the buffer using `tolower`.
+ */
+void strbuf_tolower(struct strbuf *sb);
+
+/**
+ * Compare two buffers. Returns an integer less than, equal to, or greater
+ * than zero if the first buffer is found, respectively, to be less than,
+ * to match, or be greater than the second buffer.
+ */
+int strbuf_cmp(const struct strbuf *first, const struct strbuf *second);
+
+
+/**
+ * Adding data to the buffer
+ * -------------------------
+ *
+ * NOTE: All of the functions in this section will grow the buffer as
+ * necessary.  If they fail for some reason other than memory shortage and the
+ * buffer hadn't been allocated before (i.e. the `struct strbuf` was set to
+ * `STRBUF_INIT`), then they will free() it.
+ */
+
+/**
+ * Add a single character to the buffer.
+ */
+static inline void strbuf_addch(struct strbuf *sb, int c)
+{
+	if (!strbuf_avail(sb))
+		strbuf_grow(sb, 1);
+	sb->buf[sb->len++] = c;
+	sb->buf[sb->len] = '\0';
+}
+
+/**
+ * Add a character the specified number of times to the buffer.
+ */
+void strbuf_addchars(struct strbuf *sb, int c, size_t n);
+
+/**
+ * Insert data to the given position of the buffer. The remaining contents
+ * will be shifted, not overwritten.
+ */
+void strbuf_insert(struct strbuf *sb, size_t pos, const void *, size_t);
+
+/**
+ * Insert data to the given position of the buffer giving a printf format
+ * string. The contents will be shifted, not overwritten.
+ */
+void strbuf_vinsertf(struct strbuf *sb, size_t pos, const char *fmt,
+		     va_list ap);
+
+void strbuf_insertf(struct strbuf *sb, size_t pos, const char *fmt, ...);
+
+/**
+ * Remove given amount of data from a given position of the buffer.
+ */
+void strbuf_remove(struct strbuf *sb, size_t pos, size_t len);
+
+/**
+ * Remove the bytes between `pos..pos+len` and replace it with the given
+ * data.
+ */
+void strbuf_splice(struct strbuf *sb, size_t pos, size_t len,
+		   const void *data, size_t data_len);
+
+/**
+ * Add a NUL-terminated string to the buffer. Each line will be prepended
+ * by a comment character and a blank.
+ */
+void strbuf_add_commented_lines(struct strbuf *out,
+				const char *buf, size_t size);
+
+
+/**
+ * Add data of given length to the buffer.
+ */
+void strbuf_add(struct strbuf *sb, const void *data, size_t len);
+
+/**
+ * Add a NUL-terminated string to the buffer.
+ *
+ * NOTE: This function will *always* be implemented as an inline or a macro
+ * using strlen, meaning that this is efficient to write things like:
+ *
+ *     strbuf_addstr(sb, "immediate string");
+ *
+ */
+static inline void strbuf_addstr(struct strbuf *sb, const char *s)
+{
+	strbuf_add(sb, s, strlen(s));
+}
+
+/**
+ * Copy the contents of another buffer at the end of the current one.
+ */
+void strbuf_addbuf(struct strbuf *sb, const struct strbuf *sb2);
+
+/**
+ * Join the arguments into a buffer. `delim` is put between every
+ * two arguments.
+ */
+const char *strbuf_join_argv(struct strbuf *buf, int argc,
+			     const char **argv, char delim);
+
+/**
+ * This function can be used to expand a format string containing
+ * placeholders. To that end, it parses the string and calls the specified
+ * function for every percent sign found.
+ *
+ * The callback function is given a pointer to the character after the `%`
+ * and a pointer to the struct strbuf.  It is expected to add the expanded
+ * version of the placeholder to the strbuf, e.g. to add a newline
+ * character if the letter `n` appears after a `%`.  The function returns
+ * the length of the placeholder recognized and `strbuf_expand()` skips
+ * over it.
+ *
+ * The format `%%` is automatically expanded to a single `%` as a quoting
+ * mechanism; callers do not need to handle the `%` placeholder themselves,
+ * and the callback function will not be invoked for this placeholder.
+ *
+ * All other characters (non-percent and not skipped ones) are copied
+ * verbatim to the strbuf.  If the callback returned zero, meaning that the
+ * placeholder is unknown, then the percent sign is copied, too.
+ *
+ * In order to facilitate caching and to make it possible to give
+ * parameters to the callback, `strbuf_expand()` passes a context pointer,
+ * which can be used by the programmer of the callback as she sees fit.
+ */
+typedef size_t (*expand_fn_t) (struct strbuf *sb,
+			       const char *placeholder,
+			       void *context);
+void strbuf_expand(struct strbuf *sb,
+		   const char *format,
+		   expand_fn_t fn,
+		   void *context);
+
+/**
+ * Used as callback for `strbuf_expand` to only expand literals
+ * (i.e. %n and %xNN). The context argument is ignored.
+ */
+size_t strbuf_expand_literal_cb(struct strbuf *sb,
+				const char *placeholder,
+				void *context);
+
+/**
+ * Used as callback for `strbuf_expand()`, expects an array of
+ * struct strbuf_expand_dict_entry as context, i.e. pairs of
+ * placeholder and replacement string.  The array needs to be
+ * terminated by an entry with placeholder set to NULL.
+ */
+struct strbuf_expand_dict_entry {
+	const char *placeholder;
+	const char *value;
+};
+size_t strbuf_expand_dict_cb(struct strbuf *sb,
+			     const char *placeholder,
+			     void *context);
+
+/**
+ * Append the contents of one strbuf to another, quoting any
+ * percent signs ("%") into double-percents ("%%") in the
+ * destination. This is useful for literal data to be fed to either
+ * strbuf_expand or to the *printf family of functions.
+ */
+void strbuf_addbuf_percentquote(struct strbuf *dst, const struct strbuf *src);
+
+/**
+ * Append the given byte size as a human-readable string (i.e. 12.23 KiB,
+ * 3.50 MiB).
+ */
+void strbuf_humanise_bytes(struct strbuf *buf, off_t bytes);
+
+/**
+ * Append the given byte rate as a human-readable string (i.e. 12.23 KiB/s,
+ * 3.50 MiB/s).
+ */
+void strbuf_humanise_rate(struct strbuf *buf, off_t bytes);
+
+/**
+ * Add a formatted string to the buffer.
+ */
+__attribute__((format (printf,2,3)))
+void strbuf_addf(struct strbuf *sb, const char *fmt, ...);
+
+/**
+ * Add a formatted string prepended by a comment character and a
+ * blank to the buffer.
+ */
+__attribute__((format (printf, 2, 3)))
+void strbuf_commented_addf(struct strbuf *sb, const char *fmt, ...);
+
+__attribute__((format (printf,2,0)))
+void strbuf_vaddf(struct strbuf *sb, const char *fmt, va_list ap);
+
+/**
+ * Add the time specified by `tm`, as formatted by `strftime`.
+ * `tz_offset` is in decimal hhmm format, e.g. -600 means six hours west
+ * of Greenwich, and it's used to expand %z internally.  However, tokens
+ * with modifiers (e.g. %Ez) are passed to `strftime`.
+ * `suppress_tz_name`, when set, expands %Z internally to the empty
+ * string rather than passing it to `strftime`.
+ */
+void strbuf_addftime(struct strbuf *sb, const char *fmt,
+		    const struct tm *tm, int tz_offset,
+		    int suppress_tz_name);
+
+/**
+ * Read a given size of data from a FILE* pointer to the buffer.
+ *
+ * NOTE: The buffer is rewound if the read fails. If -1 is returned,
+ * `errno` must be consulted, like you would do for `read(3)`.
+ * `strbuf_read()`, `strbuf_read_file()` and `strbuf_getline_*()`
+ * family of functions have the same behaviour as well.
+ */
+size_t strbuf_fread(struct strbuf *sb, size_t size, FILE *file);
+
+/**
+ * Read the contents of a given file descriptor. The third argument can be
+ * used to give a hint about the file size, to avoid reallocs.  If read fails,
+ * any partial read is undone.
+ */
+ssize_t strbuf_read(struct strbuf *sb, int fd, size_t hint);
+
+/**
+ * Read the contents of a given file descriptor partially by using only one
+ * attempt of xread. The third argument can be used to give a hint about the
+ * file size, to avoid reallocs. Returns the number of new bytes appended to
+ * the sb.
+ */
+ssize_t strbuf_read_once(struct strbuf *sb, int fd, size_t hint);
+
+/**
+ * Read the contents of a file, specified by its path. The third argument
+ * can be used to give a hint about the file size, to avoid reallocs.
+ * Return the number of bytes read or a negative value if some error
+ * occurred while opening or reading the file.
+ */
+ssize_t strbuf_read_file(struct strbuf *sb, const char *path, size_t hint);
+
+/**
+ * Read the target of a symbolic link, specified by its path.  The third
+ * argument can be used to give a hint about the size, to avoid reallocs.
+ */
+int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint);
+
+/**
+ * Write the whole content of the strbuf to the stream not stopping at
+ * NUL bytes.
+ */
+ssize_t strbuf_write(struct strbuf *sb, FILE *stream);
+
+/**
+ * Read a line from a FILE *, overwriting the existing contents of
+ * the strbuf.  The strbuf_getline*() family of functions share
+ * this signature, but have different line termination conventions.
+ *
+ * Reading stops after the terminator or at EOF.  The terminator
+ * is removed from the buffer before returning.  Returns 0 unless
+ * there was nothing left before EOF, in which case it returns `EOF`.
+ */
+typedef int (*strbuf_getline_fn)(struct strbuf *, FILE *);
+
+/* Uses LF as the line terminator */
+int strbuf_getline_lf(struct strbuf *sb, FILE *fp);
+
+/* Uses NUL as the line terminator */
+int strbuf_getline_nul(struct strbuf *sb, FILE *fp);
+
+/*
+ * Similar to strbuf_getline_lf(), but additionally treats a CR that
+ * comes immediately before the LF as part of the terminator.
+ * This is the most friendly version to be used to read "text" files
+ * that can come from platforms whose native text format is CRLF
+ * terminated.
+ */
+int strbuf_getline(struct strbuf *sb, FILE *file);
+
+
+/**
+ * Like `strbuf_getline`, but keeps the trailing terminator (if
+ * any) in the buffer.
+ */
+int strbuf_getwholeline(struct strbuf *sb, FILE *file, int term);
+
+/**
+ * Like `strbuf_getwholeline`, but operates on a file descriptor.
+ * It reads one character at a time, so it is very slow.  Do not
+ * use it unless you need the correct position in the file
+ * descriptor.
+ */
+int strbuf_getwholeline_fd(struct strbuf *sb, int fd, int term);
+
+/**
+ * Set the buffer to the path of the current working directory.
+ */
+int strbuf_getcwd(struct strbuf *sb);
+
+/**
+ * Add a path to a buffer, converting a relative path to an
+ * absolute one in the process.  Symbolic links are not
+ * resolved.
+ */
+void strbuf_add_absolute_path(struct strbuf *sb, const char *path);
+
+/**
+ * Canonize `path` (make it absolute, resolve symlinks, remove extra
+ * slashes) and append it to `sb`.  Die with an informative error
+ * message if there is a problem.
+ *
+ * The directory part of `path` (i.e., everything up to the last
+ * dir_sep) must denote a valid, existing directory, but the last
+ * component need not exist.
+ *
+ * Callers that don't mind links should use the more lightweight
+ * strbuf_add_absolute_path() instead.
+ */
+void strbuf_add_real_path(struct strbuf *sb, const char *path);
+
+
+/**
+ * Normalize in-place the path contained in the strbuf. See
+ * normalize_path_copy() for details. If an error occurs, the contents of "sb"
+ * are left untouched, and -1 is returned.
+ */
+int strbuf_normalize_path(struct strbuf *sb);
+
+/**
+ * Strip whitespace from a buffer. The second parameter controls if
+ * comments are considered contents to be removed or not.
+ */
+void strbuf_stripspace(struct strbuf *buf, int skip_comments);
+
+static inline int strbuf_strip_suffix(struct strbuf *sb, const char *suffix)
+{
+	if (strip_suffix_mem(sb->buf, &sb->len, suffix)) {
+		strbuf_setlen(sb, sb->len);
+		return 1;
+	} else
+		return 0;
+}
+
+/**
+ * Split str (of length slen) at the specified terminator character.
+ * Return a null-terminated array of pointers to strbuf objects
+ * holding the substrings.  The substrings include the terminator,
+ * except for the last substring, which might be unterminated if the
+ * original string did not end with a terminator.  If max is positive,
+ * then split the string into at most max substrings (with the last
+ * substring containing everything following the (max-1)th terminator
+ * character).
+ *
+ * The most generic form is `strbuf_split_buf`, which takes an arbitrary
+ * pointer/len buffer. The `_str` variant takes a NUL-terminated string,
+ * the `_max` variant takes a strbuf, and just `strbuf_split` is a convenience
+ * wrapper to drop the `max` parameter.
+ *
+ * For lighter-weight alternatives, see string_list_split() and
+ * string_list_split_in_place().
+ */
+struct strbuf **strbuf_split_buf(const char *str, size_t len,
+				 int terminator, int max);
+
+static inline struct strbuf **strbuf_split_str(const char *str,
+					       int terminator, int max)
+{
+	return strbuf_split_buf(str, strlen(str), terminator, max);
+}
+
+static inline struct strbuf **strbuf_split_max(const struct strbuf *sb,
+					       int terminator, int max)
+{
+	return strbuf_split_buf(sb->buf, sb->len, terminator, max);
+}
+
+static inline struct strbuf **strbuf_split(const struct strbuf *sb,
+					   int terminator)
+{
+	return strbuf_split_max(sb, terminator, 0);
+}
+
+/*
+ * Adds all strings of a string list to the strbuf, separated by the given
+ * separator.  For example, if sep is
+ *   ', '
+ * and slist contains
+ *   ['element1', 'element2', ..., 'elementN'],
+ * then write:
+ *   'element1, element2, ..., elementN'
+ * to str.  If only one element, just write "element1" to str.
+ */
+void strbuf_add_separated_string_list(struct strbuf *str,
+				      const char *sep,
+				      struct string_list *slist);
+
+/**
+ * Free a NULL-terminated list of strbufs (for example, the return
+ * values of the strbuf_split*() functions).
+ */
+void strbuf_list_free(struct strbuf **list);
+
+/**
+ * Add the abbreviation, as generated by find_unique_abbrev, of `sha1` to
+ * the strbuf `sb`.
+ */
+void strbuf_add_unique_abbrev(struct strbuf *sb,
+			      const struct object_id *oid,
+			      int abbrev_len);
+
+/**
+ * Launch the user preferred editor to edit a file and fill the buffer
+ * with the file's contents upon the user completing their editing. The
+ * third argument can be used to set the environment which the editor is
+ * run in. If the buffer is NULL the editor is launched as usual but the
+ * file's contents are not read into the buffer upon completion.
+ */
+int launch_editor(const char *path, struct strbuf *buffer,
+		  const char *const *env);
+
+int launch_sequence_editor(const char *path, struct strbuf *buffer,
+			   const char *const *env);
+
+void strbuf_add_lines(struct strbuf *sb,
+		      const char *prefix,
+		      const char *buf,
+		      size_t size);
+
+/**
+ * Append s to sb, with the characters '<', '>', '&' and '"' converted
+ * into XML entities.
+ */
+void strbuf_addstr_xml_quoted(struct strbuf *sb,
+			      const char *s);
+
+/**
+ * "Complete" the contents of `sb` by ensuring that either it ends with the
+ * character `term`, or it is empty.  This can be used, for example,
+ * to ensure that text ends with a newline, but without creating an empty
+ * blank line if there is no content in the first place.
+ */
+static inline void strbuf_complete(struct strbuf *sb, char term)
+{
+	if (sb->len && sb->buf[sb->len - 1] != term)
+		strbuf_addch(sb, term);
+}
+
+static inline void strbuf_complete_line(struct strbuf *sb)
+{
+	strbuf_complete(sb, '\n');
+}
+
+/*
+ * Copy "name" to "sb", expanding any special @-marks as handled by
+ * interpret_branch_name(). The result is a non-qualified branch name
+ * (so "foo" or "origin/master" instead of "refs/heads/foo" or
+ * "refs/remotes/origin/master").
+ *
+ * Note that the resulting name may not be a syntactically valid refname.
+ *
+ * If "allowed" is non-zero, restrict the set of allowed expansions. See
+ * interpret_branch_name() for details.
+ */
+void strbuf_branchname(struct strbuf *sb, const char *name,
+		       unsigned allowed);
+
+/*
+ * Like strbuf_branchname() above, but confirm that the result is
+ * syntactically valid to be used as a local branch name in refs/heads/.
+ *
+ * The return value is "0" if the result is valid, and "-1" otherwise.
+ */
+int strbuf_check_branch_ref(struct strbuf *sb, const char *name);
+
+void strbuf_addstr_urlencode(struct strbuf *sb, const char *name,
+			     int reserved);
+
+__attribute__((format (printf,1,2)))
+int printf_ln(const char *fmt, ...);
+__attribute__((format (printf,2,3)))
+int fprintf_ln(FILE *fp, const char *fmt, ...);
+
+char *xstrdup_tolower(const char *);
+char *xstrdup_toupper(const char *);
+
+/**
+ * Create a newly allocated string using printf format. You can do this easily
+ * with a strbuf, but this provides a shortcut to save a few lines.
+ */
+__attribute__((format (printf, 1, 0)))
+char *xstrvfmt(const char *fmt, va_list ap);
+__attribute__((format (printf, 1, 2)))
+char *xstrfmt(const char *fmt, ...);
+
+#endif /* STRBUF_H */