!warnings:ARM compiler - fixed code vs inconsisting with standart C, … #44
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…that cause warnings
pointer type mis-mutch, packed vs unpacked pointer type mis-mutch,
!no binary const - C standart not provide binary (0b)constants, so ARM compiler fail on it.
* remove code with goto
| } else { | ||
| /* Search for the UTF-8 string and convert it to UTF-16 */ | ||
| const uint8_t *utf8_str; | ||
| utf8_str = search_utf8_string(dev, arg->setup->wIndex, index - 1); | ||
| used = (utf8_str == NULL) ? -1 : | ||
| utf8_to_utf16(utf8_str, sd->wData, max_count); | ||
| utf8_to_utf16(utf8_str, (uint16_t*)sd->wData, max_count); |
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https://github.com/insane-adding-machines/unicore-mx/blob/master/include/unicore-mx/usb/usbstd.h#L257
sd->wData is already uint16_t
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No, that is not: sd->wData is of type "packed" uint16_t*, since it got from packed struct.
maybe there should be some comments. But , i guess, the temporary buffer preserve.buf - always aligned, so better to dropoff "packed" attribute, instead rewrite utf8_to_utf16 and search_utf8_string capable work with unaligned utf16 strings.
| if ((setup_data->bmRequestType & USB_REQ_TYPE_TYPE) != USB_REQ_TYPE_STANDARD) { | ||
| goto stall; | ||
| } | ||
| if ((setup_data->bmRequestType & USB_REQ_TYPE_TYPE) == USB_REQ_TYPE_STANDARD) { |
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Code style: 👎 from me.
| @@ -720,7 +720,7 @@ static void _control_data_callback(usbd_device *dev, | |||
| return; | |||
| } | |||
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| usbd_control_transfer_callback callback = transfer->user_data; | |||
| usbd_control_transfer_callback callback = (usbd_control_transfer_callback)transfer->user_data; | |||
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C standard says: void * will automatically cast to any other type.
and this style is more maintanable.
see: http://stackoverflow.com/a/605858/1500988
note to myself: place link to C standard text.
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But with some stricts - you can assign any pointer TO void* ,
but if you want assign some* to typed* - need casts to destination type
| @@ -897,7 +897,7 @@ void *usbd_urb_get_buffer_pointer(usbd_device *dev, usbd_urb *urb, size_t len) | |||
| return transfer->buffer; | |||
| } | |||
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| return transfer->buffer + transfer->transferred; | |||
| return (void*)((uintptr_t)transfer->buffer + transfer->transferred); | |||
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isnt transfer->buffer + transfer->transferred pointer arithmetic (valid in c).
what is the reason of writing it in a more obsured way?
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void* have no information about what entry size is. So yes - compiler is right, when error on such a trick.
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You point is valid.
GCC treat void * pointer same as char *, but that is non-standard behaviour.
| @@ -208,7 +208,7 @@ static int utf8_to_utf16(const uint8_t *utf8, uint16_t *utf16, | |||
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| /* trailing bytes payload */ | |||
| while (trailing_bytes_utf8-- > 0) { | |||
| utf32_ch = (utf32_ch << 6) | (utf8[i++] & 0b00111111); | |||
| utf32_ch = (utf32_ch << 6) | (utf8[i++] & 0x3f); | |||
| } | |||
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there was a specific reason (readability imo) to write these specific constant in binary notation.
but hexadecimal notation wont do any improvement either.
Update: (0b binary notation) dont seems to be in C specs, your point is valid.
fixed code vs inconsisting with standart C on Keil ARM compiler, that cause warnings pointer type mis-mutch, packed vs unpacked pointer type mis-mutch,
!no binary const - C standart not provide binary (0b)constants, so ARM compiler fail on it.