| Message ID | 1241036694-19940-2-git-send-email-jlayton@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Jeff Layton wrote: > It's possible for character sets to require a multi-byte null > string terminator. Add a helper function that determines the size > of the null terminator at runtime. > > Signed-off-by: Jeff Layton <jlayton@redhat.com> > --- > include/linux/nls.h | 19 +++++++++++++++++++ > 1 files changed, 19 insertions(+), 0 deletions(-) > > diff --git a/include/linux/nls.h b/include/linux/nls.h > index 6a88220..52b1a76 100644 > --- a/include/linux/nls.h > +++ b/include/linux/nls.h > @@ -58,6 +58,25 @@ static inline int nls_strnicmp(struct nls_table *t, const unsigned char *s1, > return 0; > } > > +/* > + * nls_nullsize - return length of null character for codepage > + * @codepage - codepage for which to return length of NULL terminator > + * > + * Since we can't guarantee that the null terminator will be a particular > + * length, we have to check against the codepage. If there's a problem > + * determining it, assume a single-byte NULL terminator. > + */ > +static inline int > +nls_nullsize(const struct nls_table *codepage) > +{ > + int charlen; > + char tmp[NLS_MAX_CHARSET_SIZE]; > + > + charlen = codepage->uni2char(0, tmp, NLS_MAX_CHARSET_SIZE); > + > + return charlen > 0 ? charlen : 1; > +} > + > #define MODULE_ALIAS_NLS(name) MODULE_ALIAS("nls_" __stringify(name)) > > #endif /* _LINUX_NLS_H */ Though any of the supported charsets does seem to use multi-byte null termination, it makes more sense to have forward-compatible code with negligible overhead. Acked-by: Suresh Jayaraman <sjayaraman@suse.de>
diff --git a/include/linux/nls.h b/include/linux/nls.h index 6a88220..52b1a76 100644 --- a/include/linux/nls.h +++ b/include/linux/nls.h @@ -58,6 +58,25 @@ static inline int nls_strnicmp(struct nls_table *t, const unsigned char *s1, return 0; } +/* + * nls_nullsize - return length of null character for codepage + * @codepage - codepage for which to return length of NULL terminator + * + * Since we can't guarantee that the null terminator will be a particular + * length, we have to check against the codepage. If there's a problem + * determining it, assume a single-byte NULL terminator. + */ +static inline int +nls_nullsize(const struct nls_table *codepage) +{ + int charlen; + char tmp[NLS_MAX_CHARSET_SIZE]; + + charlen = codepage->uni2char(0, tmp, NLS_MAX_CHARSET_SIZE); + + return charlen > 0 ? charlen : 1; +} + #define MODULE_ALIAS_NLS(name) MODULE_ALIAS("nls_" __stringify(name)) #endif /* _LINUX_NLS_H */
It's possible for character sets to require a multi-byte null string terminator. Add a helper function that determines the size of the null terminator at runtime. Signed-off-by: Jeff Layton <jlayton@redhat.com> --- include/linux/nls.h | 19 +++++++++++++++++++ 1 files changed, 19 insertions(+), 0 deletions(-)