/*
 * Utility functions
 * Copyright (C) 2011 Unix Solutions Ltd.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2
 * as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License (COPYING file) for more details.
 *
 */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <ctype.h>
#include <time.h>
#include <string.h>
#include <errno.h>
#include <arpa/inet.h>

#include "util.h"

static unsigned long crc_table[256] = {
  0x00000000L, 0x77073096L, 0xee0e612cL, 0x990951baL, 0x076dc419L,
  0x706af48fL, 0xe963a535L, 0x9e6495a3L, 0x0edb8832L, 0x79dcb8a4L,
  0xe0d5e91eL, 0x97d2d988L, 0x09b64c2bL, 0x7eb17cbdL, 0xe7b82d07L,
  0x90bf1d91L, 0x1db71064L, 0x6ab020f2L, 0xf3b97148L, 0x84be41deL,
  0x1adad47dL, 0x6ddde4ebL, 0xf4d4b551L, 0x83d385c7L, 0x136c9856L,
  0x646ba8c0L, 0xfd62f97aL, 0x8a65c9ecL, 0x14015c4fL, 0x63066cd9L,
  0xfa0f3d63L, 0x8d080df5L, 0x3b6e20c8L, 0x4c69105eL, 0xd56041e4L,
  0xa2677172L, 0x3c03e4d1L, 0x4b04d447L, 0xd20d85fdL, 0xa50ab56bL,
  0x35b5a8faL, 0x42b2986cL, 0xdbbbc9d6L, 0xacbcf940L, 0x32d86ce3L,
  0x45df5c75L, 0xdcd60dcfL, 0xabd13d59L, 0x26d930acL, 0x51de003aL,
  0xc8d75180L, 0xbfd06116L, 0x21b4f4b5L, 0x56b3c423L, 0xcfba9599L,
  0xb8bda50fL, 0x2802b89eL, 0x5f058808L, 0xc60cd9b2L, 0xb10be924L,
  0x2f6f7c87L, 0x58684c11L, 0xc1611dabL, 0xb6662d3dL, 0x76dc4190L,
  0x01db7106L, 0x98d220bcL, 0xefd5102aL, 0x71b18589L, 0x06b6b51fL,
  0x9fbfe4a5L, 0xe8b8d433L, 0x7807c9a2L, 0x0f00f934L, 0x9609a88eL,
  0xe10e9818L, 0x7f6a0dbbL, 0x086d3d2dL, 0x91646c97L, 0xe6635c01L,
  0x6b6b51f4L, 0x1c6c6162L, 0x856530d8L, 0xf262004eL, 0x6c0695edL,
  0x1b01a57bL, 0x8208f4c1L, 0xf50fc457L, 0x65b0d9c6L, 0x12b7e950L,
  0x8bbeb8eaL, 0xfcb9887cL, 0x62dd1ddfL, 0x15da2d49L, 0x8cd37cf3L,
  0xfbd44c65L, 0x4db26158L, 0x3ab551ceL, 0xa3bc0074L, 0xd4bb30e2L,
  0x4adfa541L, 0x3dd895d7L, 0xa4d1c46dL, 0xd3d6f4fbL, 0x4369e96aL,
  0x346ed9fcL, 0xad678846L, 0xda60b8d0L, 0x44042d73L, 0x33031de5L,
  0xaa0a4c5fL, 0xdd0d7cc9L, 0x5005713cL, 0x270241aaL, 0xbe0b1010L,
  0xc90c2086L, 0x5768b525L, 0x206f85b3L, 0xb966d409L, 0xce61e49fL,
  0x5edef90eL, 0x29d9c998L, 0xb0d09822L, 0xc7d7a8b4L, 0x59b33d17L,
  0x2eb40d81L, 0xb7bd5c3bL, 0xc0ba6cadL, 0xedb88320L, 0x9abfb3b6L,
  0x03b6e20cL, 0x74b1d29aL, 0xead54739L, 0x9dd277afL, 0x04db2615L,
  0x73dc1683L, 0xe3630b12L, 0x94643b84L, 0x0d6d6a3eL, 0x7a6a5aa8L,
  0xe40ecf0bL, 0x9309ff9dL, 0x0a00ae27L, 0x7d079eb1L, 0xf00f9344L,
  0x8708a3d2L, 0x1e01f268L, 0x6906c2feL, 0xf762575dL, 0x806567cbL,
  0x196c3671L, 0x6e6b06e7L, 0xfed41b76L, 0x89d32be0L, 0x10da7a5aL,
  0x67dd4accL, 0xf9b9df6fL, 0x8ebeeff9L, 0x17b7be43L, 0x60b08ed5L,
  0xd6d6a3e8L, 0xa1d1937eL, 0x38d8c2c4L, 0x4fdff252L, 0xd1bb67f1L,
  0xa6bc5767L, 0x3fb506ddL, 0x48b2364bL, 0xd80d2bdaL, 0xaf0a1b4cL,
  0x36034af6L, 0x41047a60L, 0xdf60efc3L, 0xa867df55L, 0x316e8eefL,
  0x4669be79L, 0xcb61b38cL, 0xbc66831aL, 0x256fd2a0L, 0x5268e236L,
  0xcc0c7795L, 0xbb0b4703L, 0x220216b9L, 0x5505262fL, 0xc5ba3bbeL,
  0xb2bd0b28L, 0x2bb45a92L, 0x5cb36a04L, 0xc2d7ffa7L, 0xb5d0cf31L,
  0x2cd99e8bL, 0x5bdeae1dL, 0x9b64c2b0L, 0xec63f226L, 0x756aa39cL,
  0x026d930aL, 0x9c0906a9L, 0xeb0e363fL, 0x72076785L, 0x05005713L,
  0x95bf4a82L, 0xe2b87a14L, 0x7bb12baeL, 0x0cb61b38L, 0x92d28e9bL,
  0xe5d5be0dL, 0x7cdcefb7L, 0x0bdbdf21L, 0x86d3d2d4L, 0xf1d4e242L,
  0x68ddb3f8L, 0x1fda836eL, 0x81be16cdL, 0xf6b9265bL, 0x6fb077e1L,
  0x18b74777L, 0x88085ae6L, 0xff0f6a70L, 0x66063bcaL, 0x11010b5cL,
  0x8f659effL, 0xf862ae69L, 0x616bffd3L, 0x166ccf45L, 0xa00ae278L,
  0xd70dd2eeL, 0x4e048354L, 0x3903b3c2L, 0xa7672661L, 0xd06016f7L,
  0x4969474dL, 0x3e6e77dbL, 0xaed16a4aL, 0xd9d65adcL, 0x40df0b66L,
  0x37d83bf0L, 0xa9bcae53L, 0xdebb9ec5L, 0x47b2cf7fL, 0x30b5ffe9L,
  0xbdbdf21cL, 0xcabac28aL, 0x53b39330L, 0x24b4a3a6L, 0xbad03605L,
  0xcdd70693L, 0x54de5729L, 0x23d967bfL, 0xb3667a2eL, 0xc4614ab8L,
  0x5d681b02L, 0x2a6f2b94L, 0xb40bbe37L, 0xc30c8ea1L, 0x5a05df1bL,
  0x2d02ef8dL
};

#define DO1(buf) crc = crc_table[((int)crc ^ (*buf++)) & 0xff] ^ (crc >> 8);
#define DO2(buf) DO1(buf); DO1(buf);
#define DO4(buf) DO2(buf); DO2(buf);
#define DO8(buf) DO4(buf); DO4(buf);

unsigned long crc32(unsigned long crc, const uint8_t *buf, unsigned int len) {
	if (!buf)
		return 0L;
	crc = crc ^ 0xffffffffL;
	while (len >= 8) {
		DO8(buf);
		len -= 8;
	}
	if (len) {
		do {
			DO1(buf);
		} while (--len);
	}
	return crc ^ 0xffffffffL;
}

int32_t boundary(int32_t exp, int32_t n) {
	return ((((n-1) >> exp) + 1) << exp);
}

uint8_t *init_4b(uint32_t val, uint8_t *b) {
	b[0] = (val >> 24) & 0xff;
	b[1] = (val >> 16) & 0xff;
	b[2] = (val >>  8) & 0xff;
	b[3] = (val      ) & 0xff;
	return b;
}

uint8_t *init_4l(uint32_t val, uint8_t *b) {
	b[3] = (val >> 24) & 0xff;
	b[2] = (val >> 16) & 0xff;
	b[1] = (val >>  8) & 0xff;
	b[0] = (val      ) & 0xff;
	return b;
}

uint8_t *init_2b(uint32_t val, uint8_t *b) {
	b[0] = (val >> 8) & 0xff;
	b[1] = (val     ) & 0xff;
	return b;
}

#ifdef __linux__
#include <sys/prctl.h>

void set_thread_name(char *thread_name) {
	prctl(PR_SET_NAME, thread_name, NULL, NULL, NULL);
}

#else
void set_thread_name(char *thread_name) {
    (void)thread_name;
}

#endif

static int decode_hex_char(char c) {
	if ((c >= '0') && (c <= '9')) return c - '0';
	if ((c >= 'A') && (c <= 'F')) return c - 'A' + 10;
	if ((c >= 'a') && (c <= 'f')) return c - 'a' + 10;
	return -1;
}

int decode_hex_string(char *hex, uint8_t *bin, int asc_len) {
	int i;
	for (i = 0; i < asc_len; i += 2) {
		int n1 = decode_hex_char(hex[i + 0]);
		int n2 = decode_hex_char(hex[i + 1]);
		if (n1 == -1 || n2 == -1)
			return -1;
		bin[i / 2] = (n1 << 4) | (n2 & 0xf);
	}
	return asc_len / 2;
}

#ifdef __MACH__
#include <mach/clock.h>
#include <mach/mach.h>
#endif

int64_t get_time(void) {
	struct timespec ts;
#ifdef __MACH__
// OS X does not have clock_gettime, use clock_get_time
	clock_serv_t cclock;
	mach_timespec_t mts;
	host_get_clock_service(mach_host_self(), CALENDAR_CLOCK, &cclock);
	clock_get_time(cclock, &mts);
	mach_port_deallocate(mach_task_self(), cclock);
	ts.tv_sec = mts.tv_sec;
	ts.tv_nsec = mts.tv_nsec;
#else
	if (clock_gettime(CLOCK_MONOTONIC, &ts) == EINVAL) // Shouldn't happen on modern Linux
		clock_gettime(CLOCK_REALTIME, &ts);
#endif
	return ts.tv_sec * 1000000ll + ts.tv_nsec / 1000;
}

#if defined(__APPLE__) || defined(__ANDROID__)
ssize_t getdelim(char **linep, size_t *np, int delim, FILE *stream)
{
	int ch;
	size_t new_len;
	ssize_t i = 0;
	char *line, *new_line;

	// Invalid input
	if (!linep || !np) {
		errno = EINVAL;
		return -1;
	}

	if (*linep == NULL || *np == 0) {
		*np = 1024;
		*linep = calloc(1, *np);
		if (*linep == NULL)
			return -1;
	}
	line = *linep;

	while ((ch = getc(stream)) != EOF) {
		if ((size_t)i > *np) {
			// Need more space
			new_len  = *np + 1024;
			new_line = realloc(*linep, new_len);
			if (!new_line)
				return -1;
			*np    = new_len;
			*linep = new_line;
		}

		line[i] = ch;
		if (ch == delim)
			break;
		i += 1;
	}

	if ((size_t)i > *np) {
		// Need more space
		new_len  = i + 2;
		new_line = realloc(*linep, new_len);
		if (!new_line)
			return -1;
		*np    = new_len;
		*linep = new_line;
	}
	line[i + 1] = '\0';

	return i > 0 ? i : -1;
}

ssize_t getline(char **linep, size_t *np, FILE *stream) {
	return getdelim(linep, np, '\n', stream);
}
#endif

unsigned int file_hex2buf(char *filename, uint8_t *buffer, unsigned int buf_size) {
	FILE *f = fopen(filename, "r");
	if (!f) {
		fprintf(stderr, "ERROR: Can't open %s: %s\n", filename, strerror(errno));
		exit(1);
	}
	memset(buffer, 0, buf_size);
	size_t len;
	ssize_t readb;
	char *line = NULL;
	unsigned int buf_pos = 0, consumed = 0;
	while ((readb = getline(&line, &len, f)) != -1) {
		ssize_t i;
		if (!readb || line[0] == '#')
			continue;
		for (i = 0; i < readb; i++) {
			char ch = toupper(line[i]);
			// Skip 0x prefixes
			if (i + 1 < readb && ch == '0' && toupper(line[i+1]) == 'X')
				continue;
			if (!isxdigit(ch))
				continue;
			ch -= ch > 64 ? 55 : 48; // hex2dec
			if (consumed % 2 == 0) {
				buffer[buf_pos] += ch << 4;
			} else {
				buffer[buf_pos] += ch;
				buf_pos++;
				if (buf_pos == buf_size)
					goto OUT;
			}
			consumed++;
		}
	}
OUT:
	free(line);
	fclose(f);

	return buf_pos;
}

int parse_host_and_port(char *input, char **hostname, char **service, int *port_set) {
	char *p;
	if (strlen(input) == 0)
		return 0;
	*hostname = input;
	if (input[0] == '[') { // Detect IPv6 static address
		p = strrchr(input, ']');
		if (!p) {
			fprintf(stderr, "ERROR: Invalid IPv6 address format: %s\n", input);
			exit(EXIT_FAILURE);
		}
		*hostname = input + 1; // Remove first [
		*p = 0x00; // Remove last ]
		char *p2 = strchr(p + 1, ':');
		if (p2) {
			*p2 = 0x00;
			*service = p2 + 1;
			*port_set = 1;
		}
	} else {
		p = strrchr(input, ':');
		if (p) {
			*p = 0x00;
			*service = p + 1;
			*port_set = 1;
		}
	}
	return 1;
}

char *my_inet_ntop(int family, struct sockaddr *addr, char *dest, int dest_len) {
	struct sockaddr_in  *addr_v4 = (struct sockaddr_in  *)addr;
	struct sockaddr_in6 *addr_v6 = (struct sockaddr_in6 *)addr;
	switch (family) {
		case AF_INET:
			return (char *)inet_ntop(AF_INET, &addr_v4->sin_addr, dest, dest_len);
			break;
		case AF_INET6:
			return (char *)inet_ntop(AF_INET6, &addr_v6->sin6_addr, dest, dest_len);
			break;
		default:
			memset(dest, 0, dest_len);
			strcpy(dest, "unknown");
			return dest;
	}
}