Re: [PATCH v3 1/3] lib/string: introduce ascii2utf16le() helper

[Richard Leitner]

On 02/06/2017 05:48 PM, Sergei Shtylyov wrote:
> Hello!
> 
> On 02/06/2017 05:03 PM, Richard Leitner wrote:
> 
>> For USB string descriptors we need to convert ASCII strings to UTF16-LE.
>> Therefore make a simple helper function (based on ascii2desc from
>> drivers/usb/core/hcd.c) for that purpose.
>>
>> Signed-off-by: Richard Leitner 
> [...]
>> diff --git a/lib/string.c b/lib/string.c
>> index ed83562..a113e3e 100644
>> --- a/lib/string.c
>> +++ b/lib/string.c
>> @@ -952,3 +952,29 @@ char *strreplace(char *s, char old, char new)
>>  return s;
>>  }
>>  EXPORT_SYMBOL(strreplace);
>> +
>> +/**
>> + * ascii2utf16le() - Helper routine for producing UTF-16LE string
>> descriptors
>> + * @s: Null-terminated ASCII (actually ISO-8859-1) string
>> + * @buf: Buffer for UTF-16LE string
>> + * @len: Length (in bytes; may be odd) of UTF-16LE buffer.
>> + *
>> + * Return: The number of bytes filled in: 2*strlen(s) or @len,
>> whichever is less
>> + */
>> +unsigned int ascii2utf16le(char const *s, u8 *buf, unsigned int len)
>> +{
>> +unsigned int n, t = 2 * strlen(s);
>> +
>> +if (len > t)
>> +len = t;
>> +n = len;
>> +while (n--) {
>> +t = (unsigned char)*s++;
>> +*buf++ = t;
>> +if (!n--)
>> +break;
>> +*buf++ = t >> 8;
> 
>Isn't it always 0?

As I will remove this function and use utf8s_to_utf16s() instead (as
suggested by Alan Stern) IMHO this issue needs no more attention.

Nonetheless, thank you for your feedback!

> 
>> +}
>> +return len;
>> +}
>> +EXPORT_SYMBOL(ascii2utf16le);

regards,
Richard L
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH v3 1/3] lib/string: introduce ascii2utf16le() helper

[Sergei Shtylyov]

Hello!

On 02/06/2017 05:03 PM, Richard Leitner wrote:


For USB string descriptors we need to convert ASCII strings to UTF16-LE.
Therefore make a simple helper function (based on ascii2desc from
drivers/usb/core/hcd.c) for that purpose.

Signed-off-by: Richard Leitner 

[...]

diff --git a/lib/string.c b/lib/string.c
index ed83562..a113e3e 100644
--- a/lib/string.c
+++ b/lib/string.c
@@ -952,3 +952,29 @@ char *strreplace(char *s, char old, char new)
return s;
 }
 EXPORT_SYMBOL(strreplace);
+
+/**
+ * ascii2utf16le() - Helper routine for producing UTF-16LE string descriptors
+ * @s: Null-terminated ASCII (actually ISO-8859-1) string
+ * @buf: Buffer for UTF-16LE string
+ * @len: Length (in bytes; may be odd) of UTF-16LE buffer.
+ *
+ * Return: The number of bytes filled in: 2*strlen(s) or @len, whichever is 
less
+ */
+unsigned int ascii2utf16le(char const *s, u8 *buf, unsigned int len)
+{
+   unsigned int n, t = 2 * strlen(s);
+
+   if (len > t)
+   len = t;
+   n = len;
+   while (n--) {
+   t = (unsigned char)*s++;
+   *buf++ = t;
+   if (!n--)
+   break;
+   *buf++ = t >> 8;


   Isn't it always 0?


+   }
+   return len;
+}
+EXPORT_SYMBOL(ascii2utf16le);


MBR, Sergei

--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH v3 1/3] lib/string: introduce ascii2utf16le() helper

[Richard Leitner]

On 02/06/2017 04:40 PM, Alan Stern wrote:
> On Mon, 6 Feb 2017, Richard Leitner wrote:
>> So it would be OK to include linux/nls.h and use utf8s_to_utf16s() in
>> drivers/usb/{core/hcd.c,misc/usb251xb.c}?
> 
> Well, we already include linux/nls.h in drivers/usb/core/message.c and
> a few files under drivers/usb/gadget.  Putting it in a few more places
> shouldn't hurt.

OK. Thanks! I will change that for v4.

regards,
Richard L
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH v3 1/3] lib/string: introduce ascii2utf16le() helper

[Alan Stern]

On Mon, 6 Feb 2017, Richard Leitner wrote:

> On 02/06/2017 04:12 PM, Alan Stern wrote:
> > On Mon, 6 Feb 2017, Richard Leitner wrote:
> > 
> >> For USB string descriptors we need to convert ASCII strings to UTF16-LE.
> >> Therefore make a simple helper function (based on ascii2desc from
> >> drivers/usb/core/hcd.c) for that purpose.
> > 
> > You know, we already have utf8s_to_utf16s() in fs/nls/nls_base.c.  
> > Maybe it doesn't do exactly what you want, but it should be pretty 
> > close.  Adding another helper function to do essentially the same thing 
> > seems unnecessary.
> 
> Thanks for that pointer. I totally agree with you.
> 
> So it would be OK to include linux/nls.h and use utf8s_to_utf16s() in
> drivers/usb/{core/hcd.c,misc/usb251xb.c}?

Well, we already include linux/nls.h in drivers/usb/core/message.c and
a few files under drivers/usb/gadget.  Putting it in a few more places
shouldn't hurt.

Alan Stern

--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH v3 1/3] lib/string: introduce ascii2utf16le() helper

[Richard Leitner]

On 02/06/2017 04:12 PM, Alan Stern wrote:
> On Mon, 6 Feb 2017, Richard Leitner wrote:
> 
>> For USB string descriptors we need to convert ASCII strings to UTF16-LE.
>> Therefore make a simple helper function (based on ascii2desc from
>> drivers/usb/core/hcd.c) for that purpose.
> 
> You know, we already have utf8s_to_utf16s() in fs/nls/nls_base.c.  
> Maybe it doesn't do exactly what you want, but it should be pretty 
> close.  Adding another helper function to do essentially the same thing 
> seems unnecessary.

Thanks for that pointer. I totally agree with you.

So it would be OK to include linux/nls.h and use utf8s_to_utf16s() in
drivers/usb/{core/hcd.c,misc/usb251xb.c}?

Thanks & regards,
Richard L
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH v3 1/3] lib/string: introduce ascii2utf16le() helper

[Alan Stern]

On Mon, 6 Feb 2017, Richard Leitner wrote:

> For USB string descriptors we need to convert ASCII strings to UTF16-LE.
> Therefore make a simple helper function (based on ascii2desc from
> drivers/usb/core/hcd.c) for that purpose.

You know, we already have utf8s_to_utf16s() in fs/nls/nls_base.c.  
Maybe it doesn't do exactly what you want, but it should be pretty 
close.  Adding another helper function to do essentially the same thing 
seems unnecessary.

Alan Stern

--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

[PATCH v3 1/3] lib/string: introduce ascii2utf16le() helper

[Richard Leitner]

For USB string descriptors we need to convert ASCII strings to UTF16-LE.
Therefore make a simple helper function (based on ascii2desc from
drivers/usb/core/hcd.c) for that purpose.

Signed-off-by: Richard Leitner 
---
 include/linux/string.h |  1 +
 lib/string.c   | 26 ++
 2 files changed, 27 insertions(+)

diff --git a/include/linux/string.h b/include/linux/string.h
index 26b6f6a..48fd0c6 100644
--- a/include/linux/string.h
+++ b/include/linux/string.h
@@ -135,6 +135,7 @@ static inline int strtobool(const char *s, bool *res)
 }
 
 int match_string(const char * const *array, size_t n, const char *string);
+unsigned int ascii2utf16le(char const *s, u8 *buf, unsigned int len);
 
 #ifdef CONFIG_BINARY_PRINTF
 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args);
diff --git a/lib/string.c b/lib/string.c
index ed83562..a113e3e 100644
--- a/lib/string.c
+++ b/lib/string.c
@@ -952,3 +952,29 @@ char *strreplace(char *s, char old, char new)
return s;
 }
 EXPORT_SYMBOL(strreplace);
+
+/**
+ * ascii2utf16le() - Helper routine for producing UTF-16LE string descriptors
+ * @s: Null-terminated ASCII (actually ISO-8859-1) string
+ * @buf: Buffer for UTF-16LE string
+ * @len: Length (in bytes; may be odd) of UTF-16LE buffer.
+ *
+ * Return: The number of bytes filled in: 2*strlen(s) or @len, whichever is 
less
+ */
+unsigned int ascii2utf16le(char const *s, u8 *buf, unsigned int len)
+{
+   unsigned int n, t = 2 * strlen(s);
+
+   if (len > t)
+   len = t;
+   n = len;
+   while (n--) {
+   t = (unsigned char)*s++;
+   *buf++ = t;
+   if (!n--)
+   break;
+   *buf++ = t >> 8;
+   }
+   return len;
+}
+EXPORT_SYMBOL(ascii2utf16le);
-- 
2.1.4

--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html