Change the encoding of strings returned by usb_string() from ISO 8859-1
to UTF-8.
Signed-off-by: Clemens Ladisch <clemens@xxxxxxxxxx>
--- linux-2.6.orig/drivers/usb/Kconfig
+++ linux-2.6/drivers/usb/Kconfig
@@ -62,6 +62,7 @@ config USB_ARCH_HAS_EHCI
config USB
tristate "Support for Host-side USB"
depends on USB_ARCH_HAS_HCD
+ select NLS # for UTF-8 strings
---help---
Universal Serial Bus (USB) is a specification for a serial bus
subsystem which offers higher speeds and more features than the
--- linux-2.6.orig/drivers/usb/core/message.c
+++ linux-2.6/drivers/usb/core/message.c
@@ -10,6 +10,7 @@
#include <linux/mm.h>
#include <linux/timer.h>
#include <linux/ctype.h>
+#include <linux/nls.h>
#include <linux/device.h>
#include <linux/scatterlist.h>
#include <linux/usb/quirks.h>
@@ -759,7 +760,7 @@ static int usb_string_sub(struct usb_dev
}
/**
- * usb_string - returns ISO 8859-1 version of a string descriptor
+ * usb_string - returns UTF-8 version of a string descriptor
* @dev: the device whose string descriptor is being retrieved
* @index: the number of the descriptor
* @buf: where to put the string
@@ -767,17 +768,10 @@ static int usb_string_sub(struct usb_dev
* Context: !in_interrupt ()
*
* This converts the UTF-16LE encoded strings returned by devices, from
- * usb_get_string_descriptor(), to null-terminated ISO-8859-1 encoded ones
- * that are more usable in most kernel contexts. Note that all characters
- * in the chosen descriptor that can't be encoded using ISO-8859-1
- * are converted to the question mark ("?") character, and this function
+ * usb_get_string_descriptor(), to null-terminated UTF-8 encoded ones
+ * that are more usable in most kernel contexts. Note that this function
* chooses strings in the first language supported by the device.
*
- * The ASCII (or, redundantly, "US-ASCII") character set is the seven-bit
- * subset of ISO 8859-1. ISO-8859-1 is the eight-bit subset of Unicode,
- * and is appropriate for use many uses of English and several other
- * Western European languages. (But it doesn't include the "Euro" symbol.)
- *
* This call is synchronous, and may not be used in an interrupt context.
*
* Returns length of the string (>= 0) or usb_control_msg status (< 0).
@@ -786,14 +780,14 @@ int usb_string(struct usb_device *dev, i
{
unsigned char *tbuf;
int err;
- unsigned int u, idx;
+ unsigned int u;
if (dev->state == USB_STATE_SUSPENDED)
return -EHOSTUNREACH;
if (size <= 0 || !buf || !index)
return -EINVAL;
buf[0] = 0;
- tbuf = kmalloc(256, GFP_NOIO);
+ tbuf = kmalloc(256 + 2, GFP_NOIO);
if (!tbuf)
return -ENOMEM;
@@ -822,17 +816,13 @@ int usb_string(struct usb_device *dev, i
if (err < 0)
goto errout;
+ for (u = 2; u < err; u += 2)
+ le16_to_cpus((u16 *)&tbuf[u]);
+ tbuf[u] = 0;
+ tbuf[u + 1] = 0;
size--; /* leave room for trailing NULL char in output buffer */
- for (idx = 0, u = 2; u < err; u += 2) {
- if (idx >= size)
- break;
- if (tbuf[u+1]) /* high byte */
- buf[idx++] = '?'; /* non ISO-8859-1 character */
- else
- buf[idx++] = tbuf[u];
- }
- buf[idx] = 0;
- err = idx;
+ err = utf8_wcstombs(buf, (u16 *)&tbuf[2], size);
+ buf[err] = 0;
if (tbuf[1] != USB_DT_STRING)
dev_dbg(&dev->dev,
@@ -845,6 +835,9 @@ int usb_string(struct usb_device *dev, i
}
EXPORT_SYMBOL_GPL(usb_string);
+/* one UTF-8-encoded 16-bit character has at most three bytes */
+#define MAX_USB_STRING_SIZE (127 * 3 + 1)
+
/**
* usb_cache_string - read a string descriptor and cache it for later use
* @udev: the device whose string descriptor is being read
@@ -862,9 +855,9 @@ char *usb_cache_string(struct usb_device
if (index <= 0)
return NULL;
- buf = kmalloc(256, GFP_KERNEL);
+ buf = kmalloc(MAX_USB_STRING_SIZE, GFP_KERNEL);
if (buf) {
- len = usb_string(udev, index, buf, 256);
+ len = usb_string(udev, index, buf, MAX_USB_STRING_SIZE);
if (len > 0) {
smallbuf = kmalloc(++len, GFP_KERNEL);
if (!smallbuf)
--
