| Message ID | 20220428080950.23509-2-masahisa.kojima@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | enable menu-driven boot device selection | expand |
On 4/28/22 10:09, Masahisa Kojima wrote: > Provide u16 string version of strlcat(). > > Signed-off-by: Masahisa Kojima <masahisa.kojima@linaro.org> > --- > Changes in v5: > - change 3rd argument from size to count, it indicates > the maximum u16 string count that dest buffer can have. > Other u16_strXXX functions in U-Boot use string count, not the > buffer size. u16_strlcat() should follow. > - update function comment to clealy describe the behavior > - use strlen() instead of strnlen(), to correctly handle > the case if the count is smaller than or equal to initial dest count > > Changes in v4: > - add blank line above the return statement > > Changes in v2: > - implement u16_strlcat(with the destination buffer size in argument) > instead of u16_strcat > include/charset.h | 17 +++++++++++++++++ > lib/charset.c | 22 ++++++++++++++++++++++ > 2 files changed, 39 insertions(+) > > diff --git a/include/charset.h b/include/charset.h > index 38908e08f0..ae356ad9a5 100644 > --- a/include/charset.h > +++ b/include/charset.h > @@ -261,6 +261,23 @@ u16 *u16_strcpy(u16 *dest, const u16 *src); > */ > u16 *u16_strdup(const void *src); > > +/** > + * u16_strlcat() - Append a length-limited, %NUL-terminated string to another > + * > + * Append the src string to the dest string, overwriting the terminating > + * null word at the end of dest, and then adds a terminating null word. > + * > + * @dest: destination buffer (must include the trailing 0x0000) > + * @src: source buffer (must include the trailing 0x0000) > + * @count: maximum number of code points that dest buffer can have, > + * including the trailing 0x0000 > + * Return: total count of the created u16 string > + * u16_strlen(src) + min(count, u16_strlen(initial dest)), > + * does not include trailing 0x0000. > + * If return value >= count, truncation occurred. > + */ > +size_t u16_strlcat(u16 *dest, const u16 *src, size_t size); > + > /** > * utf16_to_utf8() - Convert an utf16 string to utf8 > * > diff --git a/lib/charset.c b/lib/charset.c > index de201cf3b9..f295dfc11a 100644 > --- a/lib/charset.c > +++ b/lib/charset.c > @@ -416,6 +416,28 @@ u16 *u16_strdup(const void *src) > return new; > } > > +size_t u16_strlcat(u16 *dest, const u16 *src, size_t count) > +{ > + size_t destlen, srclen, ret; > + > + destlen = u16_strlen(dest); > + srclen = u16_strlen(src); > + ret = min(count, destlen) + srclen; /* does not include trailing 0x0000 */ Why should count influence the return value? Using a first call with count = 0 and src = NULL to retrieve the buffer size to realloc() and a second call after re-allocation would be a typical usage scenario. Best regards Heinrich > + > + if (destlen >= count) > + return ret; > + > + dest += destlen; > + count -= destlen; > + if (srclen >= count) > + srclen = count - 1 /* for trailing 0x0000 */; > + > + memcpy(dest, src, srclen * sizeof(u16)); > + dest[srclen] = u'\0'; > + > + return ret; > +} > + > /* Convert UTF-16 to UTF-8. */ > uint8_t *utf16_to_utf8(uint8_t *dest, const uint16_t *src, size_t size) > {
diff --git a/include/charset.h b/include/charset.h index 38908e08f0..ae356ad9a5 100644 --- a/include/charset.h +++ b/include/charset.h @@ -261,6 +261,23 @@ u16 *u16_strcpy(u16 *dest, const u16 *src); */ u16 *u16_strdup(const void *src); +/** + * u16_strlcat() - Append a length-limited, %NUL-terminated string to another + * + * Append the src string to the dest string, overwriting the terminating + * null word at the end of dest, and then adds a terminating null word. + * + * @dest: destination buffer (must include the trailing 0x0000) + * @src: source buffer (must include the trailing 0x0000) + * @count: maximum number of code points that dest buffer can have, + * including the trailing 0x0000 + * Return: total count of the created u16 string + * u16_strlen(src) + min(count, u16_strlen(initial dest)), + * does not include trailing 0x0000. + * If return value >= count, truncation occurred. + */ +size_t u16_strlcat(u16 *dest, const u16 *src, size_t size); + /** * utf16_to_utf8() - Convert an utf16 string to utf8 * diff --git a/lib/charset.c b/lib/charset.c index de201cf3b9..f295dfc11a 100644 --- a/lib/charset.c +++ b/lib/charset.c @@ -416,6 +416,28 @@ u16 *u16_strdup(const void *src) return new; } +size_t u16_strlcat(u16 *dest, const u16 *src, size_t count) +{ + size_t destlen, srclen, ret; + + destlen = u16_strlen(dest); + srclen = u16_strlen(src); + ret = min(count, destlen) + srclen; /* does not include trailing 0x0000 */ + + if (destlen >= count) + return ret; + + dest += destlen; + count -= destlen; + if (srclen >= count) + srclen = count - 1 /* for trailing 0x0000 */; + + memcpy(dest, src, srclen * sizeof(u16)); + dest[srclen] = u'\0'; + + return ret; +} + /* Convert UTF-16 to UTF-8. */ uint8_t *utf16_to_utf8(uint8_t *dest, const uint16_t *src, size_t size) {
Provide u16 string version of strlcat(). Signed-off-by: Masahisa Kojima <masahisa.kojima@linaro.org> --- Changes in v5: - change 3rd argument from size to count, it indicates the maximum u16 string count that dest buffer can have. Other u16_strXXX functions in U-Boot use string count, not the buffer size. u16_strlcat() should follow. - update function comment to clealy describe the behavior - use strlen() instead of strnlen(), to correctly handle the case if the count is smaller than or equal to initial dest count Changes in v4: - add blank line above the return statement Changes in v2: - implement u16_strlcat(with the destination buffer size in argument) instead of u16_strcat include/charset.h | 17 +++++++++++++++++ lib/charset.c | 22 ++++++++++++++++++++++ 2 files changed, 39 insertions(+)