qemu-common.h: Document cutils.c string functions

Add documentation comments for various utility string functions
which we have implemented in util/cutils.c:
 pstrcpy()
 strpadcpy()
 pstrcat()
 strstart()
 stristart()
 qemu_strnlen()
 qemu_strsep()

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
This commit is contained in:
Peter Maydell 2015-07-19 21:34:22 +01:00 committed by Michael Tokarev
parent cc47a16bcb
commit ab60366308
1 changed files with 113 additions and 1 deletions

View File

@ -148,13 +148,125 @@ static inline bool is_help_option(const char *s)
return !strcmp(s, "?") || !strcmp(s, "help");
}
/* cutils.c */
/* util/cutils.c */
/**
* pstrcpy:
* @buf: buffer to copy string into
* @buf_size: size of @buf in bytes
* @str: string to copy
*
* Copy @str into @buf, including the trailing NUL, but do not
* write more than @buf_size bytes. The resulting buffer is
* always NUL terminated (even if the source string was too long).
* If @buf_size is zero or negative then no bytes are copied.
*
* This function is similar to strncpy(), but avoids two of that
* function's problems:
* * if @str fits in the buffer, pstrcpy() does not zero-fill the
* remaining space at the end of @buf
* * if @str is too long, pstrcpy() will copy the first @buf_size-1
* bytes and then add a NUL
*/
void pstrcpy(char *buf, int buf_size, const char *str);
/**
* strpadcpy:
* @buf: buffer to copy string into
* @buf_size: size of @buf in bytes
* @str: string to copy
* @pad: character to pad the remainder of @buf with
*
* Copy @str into @buf (but *not* its trailing NUL!), and then pad the
* rest of the buffer with the @pad character. If @str is too large
* for the buffer then it is truncated, so that @buf contains the
* first @buf_size characters of @str, with no terminator.
*/
void strpadcpy(char *buf, int buf_size, const char *str, char pad);
/**
* pstrcat:
* @buf: buffer containing existing string
* @buf_size: size of @buf in bytes
* @s: string to concatenate to @buf
*
* Append a copy of @s to the string already in @buf, but do not
* allow the buffer to overflow. If the existing contents of @buf
* plus @str would total more than @buf_size bytes, then write
* as much of @str as will fit followed by a NUL terminator.
*
* @buf must already contain a NUL-terminated string, or the
* behaviour is undefined.
*
* Returns: @buf.
*/
char *pstrcat(char *buf, int buf_size, const char *s);
/**
* strstart:
* @str: string to test
* @val: prefix string to look for
* @ptr: NULL, or pointer to be written to indicate start of
* the remainder of the string
*
* Test whether @str starts with the prefix @val.
* If it does (including the degenerate case where @str and @val
* are equal) then return true. If @ptr is not NULL then a
* pointer to the first character following the prefix is written
* to it. If @val is not a prefix of @str then return false (and
* @ptr is not written to).
*
* Returns: true if @str starts with prefix @val, false otherwise.
*/
int strstart(const char *str, const char *val, const char **ptr);
/**
* stristart:
* @str: string to test
* @val: prefix string to look for
* @ptr: NULL, or pointer to be written to indicate start of
* the remainder of the string
*
* Test whether @str starts with the case-insensitive prefix @val.
* This function behaves identically to strstart(), except that the
* comparison is made after calling qemu_toupper() on each pair of
* characters.
*
* Returns: true if @str starts with case-insensitive prefix @val,
* false otherwise.
*/
int stristart(const char *str, const char *val, const char **ptr);
/**
* qemu_strnlen:
* @s: string
* @max_len: maximum number of bytes in @s to scan
*
* Return the length of the string @s, like strlen(), but do not
* examine more than @max_len bytes of the memory pointed to by @s.
* If no NUL terminator is found within @max_len bytes, then return
* @max_len instead.
*
* This function has the same behaviour as the POSIX strnlen()
* function.
*
* Returns: length of @s in bytes, or @max_len, whichever is smaller.
*/
int qemu_strnlen(const char *s, int max_len);
/**
* qemu_strsep:
* @input: pointer to string to parse
* @delim: string containing delimiter characters to search for
*
* Locate the first occurrence of any character in @delim within
* the string referenced by @input, and replace it with a NUL.
* The location of the next character after the delimiter character
* is stored into @input.
* If the end of the string was reached without finding a delimiter
* character, then NULL is stored into @input.
* If @input points to a NULL pointer on entry, return NULL.
* The return value is always the original value of *@input (and
* so now points to a NUL-terminated string corresponding to the
* part of the input up to the first delimiter).
*
* This function has the same behaviour as the BSD strsep() function.
*
* Returns: the pointer originally in @input.
*/
char *qemu_strsep(char **input, const char *delim);
time_t mktimegm(struct tm *tm);
int qemu_fls(int i);