add gzip, bzip2

'

src/cmd/gzip/gzip.c

@@ -0,0 +1,212 @@
+#include <u.h>
+#include <libc.h>
+#include <bio.h>
+#include <flate.h>
+#include "gzip.h"
+
+static	int	gzipf(char*, int);
+static	int	gzip(char*, long, int, Biobuf*);
+static	int	crcread(void *fd, void *buf, int n);
+static	int	gzwrite(void *bout, void *buf, int n);
+
+static	Biobuf	bout;
+static	ulong	crc;
+static	ulong	*crctab;
+static	int	debug;
+static	int	eof;
+static	int	level;
+static	ulong	totr;
+static	int	verbose;
+
+void
+usage(void)
+{
+	fprint(2, "usage: gzip [-vcD] [-1-9] [file ...]\n");
+	exits("usage");
+}
+
+void
+main(int argc, char *argv[])
+{
+	int i, ok, stdout;
+
+	level = 6;
+	stdout = 0;
+	ARGBEGIN{
+	case 'D':
+		debug++;
+		break;
+	case 'v':
+		verbose++;
+		break;
+	case 'c':
+		stdout = 1;
+		break;
+	case '1': case '2': case '3': case '4':
+	case '5': case '6': case '7': case '8': case '9':
+		level = ARGC() - '0';
+		break;
+	default:
+		usage();
+		break;
+	}ARGEND
+
+	crctab = mkcrctab(GZCRCPOLY);
+	ok = deflateinit();
+	if(ok != FlateOk)
+		sysfatal("deflateinit failed: %s\n", flateerr(ok));
+
+	if(argc == 0){
+		Binit(&bout, 1, OWRITE);
+		ok = gzip(nil, time(0), 0, &bout);
+		Bterm(&bout);
+	}else{
+		ok = 1;
+		for(i = 0; i < argc; i++)
+			ok &= gzipf(argv[i], stdout);
+	}
+	exits(ok ? nil: "errors");
+}
+
+static int
+gzipf(char *file, int stdout)
+{
+	Dir *dir;
+	char ofile[256], *f, *s;
+	int ifd, ofd, ok;
+
+	ifd = open(file, OREAD);
+	if(ifd < 0){
+		fprint(2, "gzip: can't open %s: %r\n", file);
+		return 0;
+	}
+	dir = dirfstat(ifd);
+	if(dir == nil){
+		fprint(2, "gzip: can't stat %s: %r\n", file);
+		close(ifd);
+		return 0;
+	}
+	if(dir->mode & DMDIR){
+		fprint(2, "gzip: can't compress a directory\n");
+		close(ifd);
+		free(dir);
+		return 0;
+	}
+
+	if(stdout){
+		ofd = 1;
+		strcpy(ofile, "<stdout>");
+	}else{
+		f = strrchr(file, '/');
+		if(f != nil)
+			f++;
+		else
+			f = file;
+		s = strrchr(f, '.');
+		if(s != nil && s != ofile && strcmp(s, ".tar") == 0){
+			*s = '\0';
+			snprint(ofile, sizeof(ofile), "%s.tgz", f);
+		}else
+			snprint(ofile, sizeof(ofile), "%s.gz", f);
+		ofd = create(ofile, OWRITE, 0666);
+		if(ofd < 0){
+			fprint(2, "gzip: can't open %s: %r\n", ofile);
+			close(ifd);
+			return 0;
+		}
+	}
+
+	if(verbose)
+		fprint(2, "compressing %s to %s\n", file, ofile);
+
+	Binit(&bout, ofd, OWRITE);
+	ok = gzip(file, dir->mtime, ifd, &bout);
+	if(!ok || Bflush(&bout) < 0){
+		fprint(2, "gzip: error writing %s: %r\n", ofile);
+		if(!stdout)
+			remove(ofile);
+	}
+	Bterm(&bout);
+	free(dir);
+	close(ifd);
+	close(ofd);
+	return ok;
+}
+
+static int
+gzip(char *file, long mtime, int ifd, Biobuf *bout)
+{
+	int flags, err;
+
+	flags = 0;
+	Bputc(bout, GZMAGIC1);
+	Bputc(bout, GZMAGIC2);
+	Bputc(bout, GZDEFLATE);
+
+	if(file != nil)
+		flags |= GZFNAME;
+	Bputc(bout, flags);
+
+	Bputc(bout, mtime);
+	Bputc(bout, mtime>>8);
+	Bputc(bout, mtime>>16);
+	Bputc(bout, mtime>>24);
+
+	Bputc(bout, 0);
+	Bputc(bout, GZOSINFERNO);
+
+	if(flags & GZFNAME)
+		Bwrite(bout, file, strlen(file)+1);
+
+	crc = 0;
+	eof = 0;
+	totr = 0;
+	err = deflate(bout, gzwrite, (void*)ifd, crcread, level, debug);
+	if(err != FlateOk){
+		fprint(2, "gzip: deflate failed: %s\n", flateerr(err));
+		return 0;
+	}
+
+	Bputc(bout, crc);
+	Bputc(bout, crc>>8);
+	Bputc(bout, crc>>16);
+	Bputc(bout, crc>>24);
+
+	Bputc(bout, totr);
+	Bputc(bout, totr>>8);
+	Bputc(bout, totr>>16);
+	Bputc(bout, totr>>24);
+
+	return 1;
+}
+
+static int
+crcread(void *fd, void *buf, int n)
+{
+	int nr, m;
+
+	nr = 0;
+	for(; !eof && n > 0; n -= m){
+		m = read((int)fd, (char*)buf+nr, n);
+		if(m <= 0){
+			eof = 1;
+			if(m < 0)
+				return -1;
+			break;
+		}
+		nr += m;
+	}
+	crc = blockcrc(crctab, crc, buf, nr);
+	totr += nr;
+	return nr;
+}
+
+static int
+gzwrite(void *bout, void *buf, int n)
+{
+	if(n != Bwrite(bout, buf, n)){
+		eof = 1;
+		return -1;
+	}
+	return n;
+}