#include <u.h>#include <libc.h> #include "git.h" Object *indexed;char *fetchbranch;char *upstream = "origin";char *packtmp = ".git/objects/pack/fetch.tmp"; intresolveremote(Hash *h, char *ref){	char buf[128], *s;	int r, f; 	ref = strip(ref);	if((r = hparse(h, ref)) != -1)		return r;	/* Slightly special handling: translate remote refs to local ones. */	if(strcmp(ref, "HEAD") == 0){		snprint(buf, sizeof(buf), ".git/HEAD");	}else if(strstr(ref, "refs/heads") == ref){		ref += strlen("refs/heads");		snprint(buf, sizeof(buf), ".git/refs/remotes/%s/%s", upstream, ref);	}else if(strstr(ref, "refs/tags") == ref){		ref += strlen("refs/tags");		snprint(buf, sizeof(buf), ".git/refs/tags/%s/%s", upstream, ref);	}else{		return -1;	} 	s = strip(buf);	if((f = open(s, OREAD)) == -1)		return -1;	if(readn(f, buf, sizeof(buf)) >= 40)		r = hparse(h, buf);	close(f); 	if(r == -1 && strstr(buf, "ref:") == buf)		return resolveremote(h, buf + strlen("ref:"));	print("resolved remote: %s\n", ref);	return r;} intrename(char *pack, char *idx, Hash h){	char name[128];	Dir st; 	nulldir(&st);	st.name = name;	snprint(name, sizeof(name), "%H.pack", h);	if(access(name, AEXIST) == 0)		fprint(2, "warning, pack %s already fetched\n", name);	else if(dirwstat(pack, &st) == -1)		return -1;	snprint(name, sizeof(name), "%H.idx", h);	if(access(name, AEXIST) == 0)		fprint(2, "warning, pack %s already indexed\n", name);	else if(dirwstat(idx, &st) == -1)		return -1;	return 0;} intcheckhash(int fd, vlong sz, Hash *hcomp){	DigestState *st;	Hash hexpect;	char buf[65536];	vlong n, r;	int nr;		if(sz < 28){		werrstr("undersize packfile");		return -1;	} 	st = nil;	n = 0;	while(n != sz - 20){		nr = sizeof(buf);		if(sz - n - 20 < sizeof(buf))			nr = sz - n - 20;		r = readn(fd, buf, nr);		if(r != nr)			return -1;		st = sha1((uchar*)buf, nr, nil, st);		n += r;	}	sha1(nil, 0, hcomp->h, st);	if(readn(fd, hexpect.h, sizeof(hexpect.h)) != sizeof(hexpect.h))		sysfatal("truncated packfile");	if(!hasheq(hcomp, &hexpect)){		werrstr("bad hash: %H != %H", *hcomp, hexpect);		return -1;	}	return 0;} intmkoutpath(char *path){	char s[128];	char *p;	int fd; 	snprint(s, sizeof(s), "%s", path);	for(p=strchr(s+1, '/'); p; p=strchr(p+1, '/')){		*p = 0;		if(access(s, AEXIST) != 0){			fd = create(s, OREAD, DMDIR | 0755);			if(fd == -1)				return -1;			close(fd);		}				*p = '/';	}	return 0;} intbranchmatch(char *br, char *pat){	char name[128]; 	if(strstr(pat, "refs/heads") == pat)		snprint(name, sizeof(name), "%s", pat);	else if(strstr(pat, "heads"))		snprint(name, sizeof(name), "refs/%s", pat);	else		snprint(name, sizeof(name), "refs/heads/%s", pat);	return strcmp(br, name) == 0;} intfetchpack(int fd, int pfd, char *packtmp){	char buf[65536], idxtmp[256], *sp[3];	Hash h, *have, *want;	int nref, refsz;	int i, n, req;	vlong packsz;	Object *o; 	nref = 0;	refsz = 16;	have = emalloc(refsz * sizeof(have[0]));	want = emalloc(refsz * sizeof(want[0]));	while(1){		n = readpkt(fd, buf, sizeof(buf));		if(n == -1)			return -1;		if(n == 0)			break;		if(strncmp(buf, "ERR ", 4) == 0)			sysfatal("%s", buf + 4);		getfields(buf, sp, nelem(sp), 1, " \t\n\r");		if(strstr(sp[1], "^{}"))			continue;		if(fetchbranch && !branchmatch(sp[1], fetchbranch))			continue;		if(refsz == nref + 1){			refsz *= 2;			have = erealloc(have, refsz * sizeof(have[0]));			want = erealloc(want, refsz * sizeof(want[0]));		}		if(hparse(&want[nref], sp[0]) == -1)			sysfatal("invalid hash %s", sp[0]);		if (resolveremote(&have[nref], sp[1]) == -1)			memset(&have[nref], 0, sizeof(have[nref]));		print("remote %s %H local %H\n", sp[1], want[nref], have[nref]);		nref++;	} 	req = 0;	for(i = 0; i < nref; i++){		if(memcmp(have[i].h, want[i].h, sizeof(have[i].h)) == 0)			continue;		if((o = readobject(want[i])) != nil){			unref(o);			continue;		}		n = snprint(buf, sizeof(buf), "want %H", want[i]);		print("want %H\n", want[i]);		if(writepkt(fd, buf, n) == -1)			sysfatal("could not send want for %H", want[i]);		req = 1; 	}	flushpkt(fd);	for(i = 0; i < nref; i++){		if(memcmp(have[i].h, Zhash.h, sizeof(Zhash.h)) == 0)			continue;		n = snprint(buf, sizeof(buf), "have %H\n", have[i]);		if(writepkt(fd, buf, n + 1) == -1)			sysfatal("could not send have for %H", have[i]);	}	if(!req){		fprint(2, "up to date\n");		flushpkt(fd);	}	n = snprint(buf, sizeof(buf), "done\n");	if(writepkt(fd, buf, n) == -1)		sysfatal("lost connection write");	if(!req)		return 0; 	if((n = readpkt(fd, buf, sizeof(buf))) == -1)		sysfatal("lost connection read");	buf[n] = 0; 	fprint(2, "fetching...\n");	packsz = 0;	while(1){		n = readn(fd, buf, sizeof buf);		if(n == 0)			break;		if(n == -1 || write(pfd, buf, n) != n)			sysfatal("could not fetch packfile: %r");		packsz += n;	}	if(seek(pfd, 0, 0) == -1)		sysfatal("packfile seek: %r");	if(checkhash(pfd, packsz, &h) == -1)		sysfatal("corrupt packfile: %r");	close(pfd);	n = strlen(packtmp) - strlen(".tmp");	memcpy(idxtmp, packtmp, n);	memcpy(idxtmp + n, ".idx", strlen(".idx") + 1);	if(indexpack(packtmp, idxtmp, h) == -1)		sysfatal("could not index fetched pack: %r");	if(rename(packtmp, idxtmp, h) == -1)		sysfatal("could not rename indexed pack: %r");	return 0;} voidusage(void){	fprint(2, "usage: %s [-b br] remote\n", argv0);	fprint(2, "\t-b br:	only fetch matching branch 'br'\n");	fprint(2, "remote:	fetch from this repository\n");	exits("usage");} voidmain(int argc, char **argv){	char proto[Nproto], host[Nhost], port[Nport];	char repo[Nrepo], path[Npath];	int fd, pfd; 	ARGBEGIN{	case 'b':	fetchbranch=EARGF(usage());	break;	case 'u':	upstream=EARGF(usage());	break;	case 'd':	chattygit++;			break;	default:	usage();			break;	}ARGEND; 	gitinit();	if(argc != 1)		usage();	fd = -1; 	if(mkoutpath(packtmp) == -1)		sysfatal("could not create %s: %r", packtmp);	if((pfd = create(packtmp, ORDWR, 0644)) == -1)		sysfatal("could not create %s: %r", packtmp); 	if(parseuri(argv[0], proto, host, port, path, repo) == -1)		sysfatal("bad uri %s", argv[0]);	if(strcmp(proto, "ssh") == 0 || strcmp(proto, "git+ssh") == 0)		fd = dialssh(host, port, path, "upload");	else if(strcmp(proto, "git") == 0)		fd = dialgit(host, port, path, "upload");	else if(strcmp(proto, "http") == 0 || strcmp(proto, "git+http") == 0)		sysfatal("http clone not implemented");	else		sysfatal("unknown protocol %s", proto);		if(fd == -1)		sysfatal("could not dial %s:%s: %r", proto, host);	if(fetchpack(fd, pfd, packtmp) == -1)		sysfatal("fetch failed: %r");	exits(nil);}