Util.cpp

#include "Util.h"
#include <iostream>
#include <iomanip>
#include <unicode/unistr.h>

extern "C" {
#include <ctype.h>
#include <sys/poll.h>
}

static constexpr uint32_t CRC32Table[] = {
    0x00000000, 0x04c11db7, 0x09823b6e, 0x0d4326d9,
    0x130476dc, 0x17c56b6b, 0x1a864db2, 0x1e475005,
    0x2608edb8, 0x22c9f00f, 0x2f8ad6d6, 0x2b4bcb61,
    0x350c9b64, 0x31cd86d3, 0x3c8ea00a, 0x384fbdbd,
    0x4c11db70, 0x48d0c6c7, 0x4593e01e, 0x4152fda9,
    0x5f15adac, 0x5bd4b01b, 0x569796c2, 0x52568b75,
    0x6a1936c8, 0x6ed82b7f, 0x639b0da6, 0x675a1011,
    0x791d4014, 0x7ddc5da3, 0x709f7b7a, 0x745e66cd,
    0x9823b6e0, 0x9ce2ab57, 0x91a18d8e, 0x95609039,
    0x8b27c03c, 0x8fe6dd8b, 0x82a5fb52, 0x8664e6e5,
    0xbe2b5b58, 0xbaea46ef, 0xb7a96036, 0xb3687d81,
    0xad2f2d84, 0xa9ee3033, 0xa4ad16ea, 0xa06c0b5d,
    0xd4326d90, 0xd0f37027, 0xddb056fe, 0xd9714b49,
    0xc7361b4c, 0xc3f706fb, 0xceb42022, 0xca753d95,
    0xf23a8028, 0xf6fb9d9f, 0xfbb8bb46, 0xff79a6f1,
    0xe13ef6f4, 0xe5ffeb43, 0xe8bccd9a, 0xec7dd02d,
    0x34867077, 0x30476dc0, 0x3d044b19, 0x39c556ae,
    0x278206ab, 0x23431b1c, 0x2e003dc5, 0x2ac12072,
    0x128e9dcf, 0x164f8078, 0x1b0ca6a1, 0x1fcdbb16,
    0x018aeb13, 0x054bf6a4, 0x0808d07d, 0x0cc9cdca,
    0x7897ab07, 0x7c56b6b0, 0x71159069, 0x75d48dde,
    0x6b93dddb, 0x6f52c06c, 0x6211e6b5, 0x66d0fb02,
    0x5e9f46bf, 0x5a5e5b08, 0x571d7dd1, 0x53dc6066,
    0x4d9b3063, 0x495a2dd4, 0x44190b0d, 0x40d816ba,
    0xaca5c697, 0xa864db20, 0xa527fdf9, 0xa1e6e04e,
    0xbfa1b04b, 0xbb60adfc, 0xb6238b25, 0xb2e29692,
    0x8aad2b2f, 0x8e6c3698, 0x832f1041, 0x87ee0df6,
    0x99a95df3, 0x9d684044, 0x902b669d, 0x94ea7b2a,
    0xe0b41de7, 0xe4750050, 0xe9362689, 0xedf73b3e,
    0xf3b06b3b, 0xf771768c, 0xfa325055, 0xfef34de2,
    0xc6bcf05f, 0xc27dede8, 0xcf3ecb31, 0xcbffd686,
    0xd5b88683, 0xd1799b34, 0xdc3abded, 0xd8fba05a,
    0x690ce0ee, 0x6dcdfd59, 0x608edb80, 0x644fc637,
    0x7a089632, 0x7ec98b85, 0x738aad5c, 0x774bb0eb,
    0x4f040d56, 0x4bc510e1, 0x46863638, 0x42472b8f,
    0x5c007b8a, 0x58c1663d, 0x558240e4, 0x51435d53,
    0x251d3b9e, 0x21dc2629, 0x2c9f00f0, 0x285e1d47,
    0x36194d42, 0x32d850f5, 0x3f9b762c, 0x3b5a6b9b,
    0x0315d626, 0x07d4cb91, 0x0a97ed48, 0x0e56f0ff,
    0x1011a0fa, 0x14d0bd4d, 0x19939b94, 0x1d528623,
    0xf12f560e, 0xf5ee4bb9, 0xf8ad6d60, 0xfc6c70d7,
    0xe22b20d2, 0xe6ea3d65, 0xeba91bbc, 0xef68060b,
    0xd727bbb6, 0xd3e6a601, 0xdea580d8, 0xda649d6f,
    0xc423cd6a, 0xc0e2d0dd, 0xcda1f604, 0xc960ebb3,
    0xbd3e8d7e, 0xb9ff90c9, 0xb4bcb610, 0xb07daba7,
    0xae3afba2, 0xaafbe615, 0xa7b8c0cc, 0xa379dd7b,
    0x9b3660c6, 0x9ff77d71, 0x92b45ba8, 0x9675461f,
    0x8832161a, 0x8cf30bad, 0x81b02d74, 0x857130c3,
    0x5d8a9099, 0x594b8d2e, 0x5408abf7, 0x50c9b640,
    0x4e8ee645, 0x4a4ffbf2, 0x470cdd2b, 0x43cdc09c,
    0x7b827d21, 0x7f436096, 0x7200464f, 0x76c15bf8,
    0x68860bfd, 0x6c47164a, 0x61043093, 0x65c52d24,
    0x119b4be9, 0x155a565e, 0x18197087, 0x1cd86d30,
    0x029f3d35, 0x065e2082, 0x0b1d065b, 0x0fdc1bec,
    0x3793a651, 0x3352bbe6, 0x3e119d3f, 0x3ad08088,
    0x2497d08d, 0x2056cd3a, 0x2d15ebe3, 0x29d4f654,
    0xc5a92679, 0xc1683bce, 0xcc2b1d17, 0xc8ea00a0,
    0xd6ad50a5, 0xd26c4d12, 0xdf2f6bcb, 0xdbee767c,
    0xe3a1cbc1, 0xe760d676, 0xea23f0af, 0xeee2ed18,
    0xf0a5bd1d, 0xf464a0aa, 0xf9278673, 0xfde69bc4,
    0x89b8fd09, 0x8d79e0be, 0x803ac667, 0x84fbdbd0,
    0x9abc8bd5, 0x9e7d9662, 0x933eb0bb, 0x97ffad0c,
    0xafb010b1, 0xab710d06, 0xa6322bdf, 0xa2f33668,
    0xbcb4666d, 0xb8757bda, 0xb5365d03, 0xb1f740b4
};


namespace Util {

	bool waitFor(uint32_t timeout, std::function<bool ()> const &condition, timespec delay) {
		timeval tv, end;
		gettimeofday(&end, nullptr);
		end.tv_usec += timeout;
		if(end.tv_usec > 1000000) {
			end.tv_sec += end.tv_usec/1000000;
			end.tv_usec %= 1000000;
		}
		do {
			if(condition())
				return true;
			nanosleep(&delay, nullptr);
			gettimeofday(&tv, nullptr);
		} while(tv.tv_sec < end.tv_sec || (tv.tv_sec == end.tv_sec && tv.tv_usec < end.tv_usec));
		return false;
	}

	bool waitForData(int fd, uint32_t timeout) {
		pollfd p;
		p.fd = fd;
		p.events = POLLIN;
		return poll(&p, 1, timeout);
	}

	void hexdump(void const * const data, size_t size, std::ostream &where, std::string const &indent, uint8_t bytesPerRow) {
		if(!size)
			return;

		SaveIOState isr(where);
		unsigned char tmp[17];
		uint8_t const maxOffset = bytesPerRow-1;
		tmp[16]=0;
		where << std::hex << std::setfill('0') << indent;
		for(size_t i=0; i<size; i++) {
			unsigned char const c=static_cast<unsigned char const * const>(data)[i];
			if(isprint(c))
				tmp[i%bytesPerRow]=c;
			else
				tmp[i%bytesPerRow]='.';
			where << std::setw(2) << static_cast<uint16_t>(c) << " ";
			if(i%bytesPerRow == maxOffset) {
				where << tmp << std::endl;
				if(i<size-1)
					where << indent;
			}
		}
		if(size%bytesPerRow) {
			tmp[size%bytesPerRow]=0;
			for(int i=0; i<bytesPerRow-(size%bytesPerRow); i++)
				where << "   ";
			where << tmp << std::endl;
		}
	}

	uint32_t crc32(unsigned char const * const data, size_t size, uint32_t previous) {
		uint32_t crc = previous;
		for(size_t i=0; i<size; i++) {
			crc = (crc << 8) ^ CRC32Table[((crc >> 24) ^ (data[i] & 0xff)) & 0xff];
		}
		return crc;
	}

	std::string StringFromDVB(char const * const c) {
		if(!c || !*c)
			return std::string();
		char const *pos=c+1;
		uint8_t length=c[0];
		std::string charset="iso-8859-1";
		if(*pos < 0x20) {
			if(*pos <= 0x0b)
				// 0x08 is a bit of an exception because 8859-12 was
				// never published - but 0x08 is reserved for future
				// use, so unless and until it becomes something else,
				// let's assume it's 8859-12 draft
				charset = "iso-8859-" + std::to_string(static_cast<int>(*pos) + 4);
			else if(*pos == 0x10) {
				// FIXME we aren't handling "reserved for future use"
				// cases here (Annex A table A.4)
				pos += 2;
				length -= 2;
				charset = "iso-8859-" + std::to_string(*pos);
			}
			else if(*pos == 0x11)
				charset = "iso-10646";
			else if(*pos == 0x12)
				charset = "EUC-KR"; // FIXME standard says KSX1001-2004, but ICU doesn't know that one. Is EUC-KR close enough?
			else if(*pos == 0x13)
				charset = "gb2312-1980";
			else if(*pos == 0x14)
				charset = "Big5";
			else if(*pos == 0x15)
				charset = "UTF-8";
			pos++;
			length--;
		}
		std::string result;
		return UnicodeString(pos, static_cast<int32_t>(length), charset.c_str()).toUTF8String<std::string>(result);
	}
}