bin/pax/buf_subs.c

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65 static char *bufend;			/* end or last char in i/o buffer */
66 static char *bufpt;			/* read/write point in i/o buffer */
67 int blksz = MAXBLK;			/* block input/output size in bytes */
68 int wrblksz;				/* user spec output size in bytes */
77  *	set up the buffering system to operate in a write mode
183  *	backwards in the archive to be positioned BEFORE the trailer. Two
186  *	stored in the read (soon to become write) buffer. We may have to move
196  *	in the archive.
219 	 * in the last archive volume read. (If a is set we still use rdblksz
234 	 * Calculate bytes to move back and move in front of record where we
235 	 * need to start writing from. Remember we have to add in any padding
236 	 * that might be in the buffer after the trailer in the last block. We
246 	 * We may have gone too far if there is valid data in the block we are
247 	 * now in front of, read up the block and position the pointer after
254 		 * the old rdblksz (now in blksz). If ar_rev() fouls up the
282 	 * that is handled in ar_set_wr(). From now on we operate under normal
367  *	overlap a block boundary (as in the case we are trying to recover a
384  *	skip forward in the archive during an archive read. Used to get quickly
398 	 * consume what data we have in the buffer. If we have to move forward
471  *	fill the write buffer from data passed to it in a buffer (usually used
517 rd_wrbuf(char *in, int cpcnt)
545 		memcpy(in, bufpt, cnt);
548 		in += cnt;
651  *	so that it can be compared to the value stored in the header
722 	 * gets updated in the file. We force the last block of zeros to be
737 	 * calculated crc to the crc stored in the archive
747  *	just as in rd_wrfile() we use a special write function to write the
765 	 * check for holes in the source file. If none, we will use regular
814 	 * gets updated in the file. We force the last block of zeros to be
828  *	Number of bytes of data in the read buffer, -1 for read error, and
829  *	0 when finished (user specified termination in ar_next()).
855 		 * but in case we have not determined yet the format,
874  *	bytes in the buffer at the point of the flush. When we change archives
905 		 * (one or more times), or if there is now free space left in
907 		 * bytes in the buffer, (the blocksize, at the point we were
908 		 * CALLED). Push has the amount of "extra" data in the buffer
950 			 * we warned the user in ar_write().... but this means