#include <stdio.h>#include "lpc10.h"/*Write the bits in bits[0] through bits[len-1] to file f, in "packed"format.bits is expected to be an array of len integer values, where eachinteger is 0 to represent a 0 bit, and any other value represents a 1bit.  This bit string is written to the file f in the form of several8 bit characters.  If len is not a multiple of 8, then the lastcharacter is padded with 0 bits -- the padding is in the leastsignificant bits of the last byte.  The 8 bit characters are "filled"in order from most significant bit to least significant.*/voidwrite_bits(FILE *f, INT32 *bits, int len){    int             i;		/* generic loop variable */    unsigned char   mask;	/* The next bit position within the				   variable "data" to place the next				   bit. */    unsigned char   data;	/* The contents of the next byte to				   place in the output. */    /* Fill in the array bits.     * The first compressed output bit will be the most significant     * bit of the byte, so initialize mask to 0x80.  The next byte of     * compressed data is initially 0, and the desired bits will be     * turned on below.     */    mask = 0x80;    data = 0;    for (i = 0; i < len; i++) {	/* Turn on the next bit of output data, if necessary. */	if (bits[i]) {	    data |= mask;	}	/*	 * If the byte data is full, determined by mask becoming 0,	 * then write the byte to the output file, and reinitialize	 * data and mask for the next output byte.  Also add the byte	 * if (i == len-1), because if len is not a multiple of 8,	 * then mask won't yet be 0.  */	mask >>= 1;	if ((mask == 0) || (i == len-1)) {	    putc(data, f);	    data = 0;	    mask = 0x80;	}    }}/*Read bits from file f into bits[0] through bits[len-1], in "packed"format.Read ceiling(len/8) characters from file f, if that many are availableto read, otherwise read to the end of the file.  The first character's8 bits, in order from MSB to LSB, are used to fill bits[0] throughbits[7].  The second character's bits are used to fill bits[8] throughbits[15], and so on.  If ceiling(len/8) characters are available toread, and len is not a multiple of 8, then some of the leastsignificant bits of the last character read are completely ignored.Every entry of bits[] that is modified is changed to either a 0 or a1.The number of bits successfully read is returned, and is always in therange 0 to len, inclusive.  If it is less than len, it will always bea multiple of 8.*/intread_bits(FILE *f, INT32 *bits, int len){    int             i;		/* generic loop variable */    int             c;    /* Unpack the array bits into coded_frame. */    for (i = 0; i < len; i++) {	if (i % 8 == 0) {	    c = getc(f);	    if (c == EOF) {		return (i);	    }	}	if (c & (0x80 >> (i & 7))) {	    bits[i] = 1;	} else {	    bits[i] = 0;	}    }    return (len);}