add gzip, bzip2

'

src/cmd/bzip2/bunzip2.c

@@ -0,0 +1,186 @@
+#include <u.h>
+#include <libc.h>
+#include <bio.h>
+#include "bzlib.h"
+
+static	Biobuf	bin;
+static	int	debug;
+static	int	verbose;
+static	char	*delfile;
+static	char	*infile;
+static	int	bunzipf(char *file, int stdout);
+static	int	bunzip(int ofd, char *ofile, Biobuf *bin);
+
+void
+usage(void)
+{
+	fprint(2, "usage: bunzip2 [-cvD] [file ...]\n");
+	exits("usage");
+}
+
+void
+main(int argc, char **argv)
+{
+	int i, ok, stdout;
+
+	stdout = 0;
+	ARGBEGIN{
+	case 'D':
+		debug++;
+		break;
+	case 'c':
+		stdout++;
+		break;
+	case 'v':
+		verbose++;
+		break;
+	}ARGEND
+
+	if(argc == 0){
+		Binit(&bin, 0, OREAD);
+		infile = "<stdin>";
+		ok = bunzip(1, "<stdout>", &bin);
+	}else{
+		ok = 1;
+		for(i = 0; i < argc; i++)
+			ok &= bunzipf(argv[i], stdout);
+	}
+
+	exits(ok ? nil: "errors");
+}
+
+static int
+bunzipf(char *file, int stdout)
+{
+	char ofile[64], *s;
+	int ofd, ifd, ok;
+
+	infile = file;
+	ifd = open(file, OREAD);
+	if(ifd < 0){
+		fprint(2, "gunzip: can't open %s: %r\n", file);
+		return 0;
+	}
+
+	Binit(&bin, ifd, OREAD);
+	if(Bgetc(&bin) != 'B' || Bgetc(&bin) != 'Z' || Bgetc(&bin) != 'h'){
+		fprint(2, "bunzip2: %s is not a bzip2 file\n", file);
+		Bterm(&bin);
+		close(ifd);
+		return 0;
+	}
+	Bungetc(&bin);
+	Bungetc(&bin);
+	Bungetc(&bin);
+
+	if(stdout){
+		ofd = 1;
+		strcpy(ofile, "<stdout>");
+	}else{
+		s = strrchr(file, '/');
+		if(s != nil)
+			s++;
+		else
+			s = file;
+		strecpy(ofile, ofile+sizeof ofile, s);
+		s = strrchr(ofile, '.');
+		if(s != nil && s != ofile && strcmp(s, ".bz2") == 0)
+			*s = '\0';
+		else if(s != nil && (strcmp(s, ".tbz") == 0 || strcmp(s, ".tbz2") == 0))
+			strcpy(s, ".tar");
+		else if(strcmp(file, ofile) == 0){
+			fprint(2, "bunzip2: can't overwrite %s\n", file);
+			Bterm(&bin);
+			close(ifd);
+			return 0;
+		}
+
+		ofd = create(ofile, OWRITE, 0666);
+		if(ofd < 0){
+			fprint(2, "bunzip2: can't create %s: %r\n", ofile);
+			Bterm(&bin);
+			close(ifd);
+			return 0;
+		}
+		delfile = ofile;
+	}
+
+	ok = bunzip(ofd, ofile, &bin);
+	Bterm(&bin);
+	close(ifd);
+	if(!ok){
+		fprint(2, "bunzip2: can't write %s: %r\n", ofile);
+		if(delfile)
+			remove(delfile);
+	}
+	delfile = nil;
+	if(!stdout && ofd >= 0)
+		close(ofd);
+	return ok;
+}
+
+static int
+bunzip(int ofd, char *ofile, Biobuf *bin)
+{
+	int e, n, done, onemore;
+	char buf[8192];
+	char obuf[8192];
+	Biobuf bout;
+	bz_stream strm;
+
+	USED(ofile);
+
+	memset(&strm, 0, sizeof strm);
+	BZ2_bzDecompressInit(&strm, verbose, 0);
+
+	strm.next_in = buf;
+	strm.avail_in = 0;
+	strm.next_out = obuf;
+	strm.avail_out = sizeof obuf;
+
+	done = 0;
+	Binit(&bout, ofd, OWRITE);
+
+	/*
+	 * onemore is a crummy hack to go 'round the loop
+	 * once after we finish, to flush the output buffer.
+	 */
+	onemore = 1;
+	SET(e);
+	do {
+		if(!done && strm.avail_in < sizeof buf) {
+			if(strm.avail_in)
+				memmove(buf, strm.next_in, strm.avail_in);
+			
+			n = Bread(bin, buf+strm.avail_in, sizeof(buf)-strm.avail_in);
+			if(n <= 0)
+				done = 1;
+			else
+				strm.avail_in += n;
+			strm.next_in = buf;
+		}
+		if(strm.avail_out < sizeof obuf) {
+			Bwrite(&bout, obuf, sizeof(obuf)-strm.avail_out);
+			strm.next_out = obuf;
+			strm.avail_out = sizeof obuf;
+		}
+		if(onemore == 0)
+			break;
+		if(strm.avail_in == 0 && strm.avail_out == sizeof obuf)
+			break;
+	} while((e=BZ2_bzDecompress(&strm)) == BZ_OK || onemore--);
+
+	if(e != BZ_STREAM_END) {
+		fprint(2, "bunzip2: decompress failed\n");
+		return 0;
+	}
+
+	if(BZ2_bzDecompressEnd(&strm) != BZ_OK) {
+		fprint(2, "bunzip2: decompress end failed (can't happen)\n");
+		return 0;
+	}
+
+	Bterm(&bout);
+
+	return 1;
+}