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#include <sstream>
#include <string>
#include "misc.h"
#include "inttypes.h"

namespace nitrokey {
namespace misc {

std::string hexdump(const char *p, size_t size) { 
	std::stringstream out;
	char formatbuf[128];
	const char *pstart = p;

	for (const char *pend = p + size; p < pend;) {
		snprintf(formatbuf, 128, "%04x\t", p - pstart);
		out << formatbuf;

		for (const char *le = p + 16; p < le && p < pend; p++) {
			snprintf(formatbuf, 128, "%02x ", uint8_t(*p));
			out << formatbuf;
		}
		out << std::endl;
	}
	return out.str();
}

static uint32_t _crc32 (uint32_t crc, uint32_t data)
{
	int i;
    crc = crc ^ data;

    for (i = 0; i < 32; i++) {
        if (crc & 0x80000000)
            crc = (crc << 1) ^ 0x04C11DB7;  // polynomial used in STM32
        else
            crc = (crc << 1);
	}

    return crc;
}

uint32_t stm_crc32(const uint8_t *data, size_t size) {
	uint32_t crc = 0xffffffff;
	const uint32_t *pend = (const uint32_t *)(data + size);
	for (const uint32_t *p = (const uint32_t *)(data); p < pend; p++)
		crc = _crc32(crc, *p);
	return crc;
}

}
}