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Auto calculation of array size

Dear all,

For some reason, I need to declare an array like that

#define STRING2_DESCRIPTOR_LENGTH 16
BYTE code product_string_descriptor[] = {
	STRING2_DESCRIPTOR_LENGTH,
	0x03,
	'U', 0x00,
	'S', 0x00,
	'B', 0x00,
	' ', 0x00,
	'H', 0x00,
	'U', 0x00,
	'B', 0x00
};

When I add characters to the array, I also need to increase STRING_DESCRIPTOR_LENGTH manually.
Do you know some way to calculate the size of the array automatically?
I know in assembly, I can do something like that

product_string_descriptor:
	DB	end - $
	DB	0x03,
	DB	'U', 0x00
	DB	'S', 0x00
	DB	'B', 0x00
	DB	' ', 0x00
	DB	'H', 0x00
	DB	'U', 0x00
	DB	'B', 0x00
end:

How about in C?

Parents

0 Jon Ward over 22 years ago in reply to Suppressor Chan

OK, Then what about the following:

#define USB_DESC "\03" "USB HUB"

#define USB_DESC_LENGTH (sizeof(USB_DESC) - 1)  /*** -1 for null terminator ***/

static unsigned char code product_string_descriptor[] = {
    USB_DESC_LENGTH,
    USB_DESC
};

This compiles just fine on my computer with C51 V7.05.

Jon

Reply

0 Jon Ward over 22 years ago in reply to Suppressor Chan

OK, Then what about the following:

#define USB_DESC "\03" "USB HUB"

#define USB_DESC_LENGTH (sizeof(USB_DESC) - 1)  /*** -1 for null terminator ***/

static unsigned char code product_string_descriptor[] = {
    USB_DESC_LENGTH,
    USB_DESC
};

This compiles just fine on my computer with C51 V7.05.

Jon

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