Hi Frédéric,
On Tue, Jul 8, 2025 at 3:08 AM Frédéric Danis
<frederic.danis@xxxxxxxxxxxxx> wrote:
>
> This adds the strtoutf8 function that truncate a string before the
> first non UTF-8 character.
> This truncation is done in place.
> ---
> src/shared/util.c | 42 ++++++++++++++++++++++++++++++++++++++++++
> src/shared/util.h | 1 +
> 2 files changed, 43 insertions(+)
>
> diff --git a/src/shared/util.c b/src/shared/util.c
> index 5d3a14d96..5262458cb 100644
> --- a/src/shared/util.c
> +++ b/src/shared/util.c
> @@ -1959,3 +1959,45 @@ bool argsisutf8(int argc, char *argv[])
>
> return true;
> }
> +
> +char *strtoutf8(char *str, size_t len)
> +{
> + size_t i = 0;
> +
> + while (i < len) {
> + unsigned char c = str[i];
> + size_t size = 0;
> +
> + /* Check the first byte to determine the number of bytes in the
> + * UTF-8 character.
> + */
> + if ((c & 0x80) == 0x00)
> + size = 1;
> + else if ((c & 0xE0) == 0xC0)
> + size = 2;
> + else if ((c & 0xF0) == 0xE0)
> + size = 3;
> + else if ((c & 0xF8) == 0xF0)
> + size = 4;
> + else
> + /* Invalid UTF-8 sequence */
> + goto done;
> +
> + /* Check the following bytes to ensure they have the correct
> + * format.
> + */
> + for (size_t j = 1; j < size; ++j) {
> + if (i + j > len || (str[i + j] & 0xC0) != 0x80)
> + /* Invalid UTF-8 sequence */
> + goto done;
> + }
> +
> + /* Move to the next character */
> + i += size;
> + }
Perhaps we should split this part on its own function or use strisutf8
but somehow return the last valid character found.
> +
> +done:
> + /* Truncate to the longest valid UTF-8 string */
> + memset(str + i, 0, len - i);
> + return str;
> +}
> diff --git a/src/shared/util.h b/src/shared/util.h
> index dd357fb93..6fc02a9dc 100644
> --- a/src/shared/util.h
> +++ b/src/shared/util.h
> @@ -92,6 +92,7 @@ int strsuffix(const char *str, const char *suffix);
> char *strstrip(char *str);
> bool strisutf8(const char *str, size_t length);
> bool argsisutf8(int argc, char *argv[]);
> +char *strtoutf8(char *str, size_t len);
>
> void *util_malloc(size_t size);
> void *util_memdup(const void *src, size_t size);
> --
> 2.43.0
>
>
--
Luiz Augusto von Dentz
