git: got git?

Add a snapshot of git9 to 9front.

1 files changed, 459 insertions, 0 deletions

diff --git a/sys/src/cmd/git/proto.c b/sys/src/cmd/git/proto.c
new file mode 100644
index 000000000..19c0889af
--- /dev/null
+++ b/sys/src/cmd/git/proto.c
@@ -0,0 +1,459 @@
+#include <u.h>
+#include <libc.h>
+#include <ctype.h>
+
+#include "git.h"
+
+#define Useragent	"useragent git/2.24.1"
+#define Contenthdr	"headers Content-Type: application/x-git-%s-pack-request"
+#define Accepthdr	"headers Accept: application/x-git-%s-pack-result"
+
+enum {
+	Nproto	= 16,
+	Nport	= 16,
+	Nhost	= 256,
+	Npath	= 128,
+	Nrepo	= 64,
+	Nbranch	= 32,
+};
+
+void
+tracepkt(int v, char *pfx, char *b, int n)
+{
+	char *f;
+	int o, i;
+
+	if(chattygit < v)
+		return;
+	o = 0;
+	f = emalloc(n*4 + 1);
+	for(i = 0; i < n; i++){
+		if(isprint(b[i])){
+			f[o++] = b[i];
+			continue;
+		}
+		f[o++] = '\\';
+		switch(b[i]){
+		case '\\':	f[o++] = '\\';	break;
+		case '\n':	f[o++] = 'n';	break;
+		case '\r':	f[o++] = 'r';	break;
+		case '\v':	f[o++] = 'v';	break;
+		case '\0':	f[o++] = '0';	break;
+		default:
+			f[o++] = 'x';
+			f[o++] = "0123456789abcdef"[(b[i]>>4)&0xf];
+			f[o++] = "0123456789abcdef"[(b[i]>>0)&0xf];
+			break;
+		}
+	}
+	f[o] = '\0';
+	fprint(2, "%s %04x:\t%s\n", pfx, n, f);
+	free(f);
+}
+
+int
+readpkt(Conn *c, char *buf, int nbuf)
+{
+	char len[5];
+	char *e;
+	int n;
+
+	if(readn(c->rfd, len, 4) == -1)
+		return -1;
+	len[4] = 0;
+	n = strtol(len, &e, 16);
+	if(n == 0){
+		dprint(1, "=r=> 0000\n");
+		return 0;
+	}
+	if(e != len + 4 || n <= 4)
+		sysfatal("pktline: bad length '%s'", len);
+	n  -= 4;
+	if(n >= nbuf)
+		sysfatal("pktline: undersize buffer");
+	if(readn(c->rfd, buf, n) != n)
+		return -1;
+	buf[n] = 0;
+	tracepkt(1, "=r=>", buf, n);
+	return n;
+}
+
+int
+writepkt(Conn *c, char *buf, int nbuf)
+{
+	char len[5];
+
+
+	snprint(len, sizeof(len), "%04x", nbuf + 4);
+	if(write(c->wfd, len, 4) != 4)
+		return -1;
+	if(write(c->wfd, buf, nbuf) != nbuf)
+		return -1;
+	tracepkt(1, "<=w=", buf, nbuf);
+	return 0;
+}
+
+int
+flushpkt(Conn *c)
+{
+	dprint(1, "<=w= 0000\n");
+	return write(c->wfd, "0000", 4);
+}
+
+static void
+grab(char *dst, int n, char *p, char *e)
+{
+	int l;
+
+	l = e - p;
+	if(l >= n)
+		sysfatal("overlong component");
+	memcpy(dst, p, l);
+	dst[l] = 0;
+}
+
+static int
+parseuri(char *uri, char *proto, char *host, char *port, char *path, char *repo)
+{
+	char *s, *p, *q;
+	int n, hasport;
+	print("uri: \"%s\"\n", uri);
+
+	p = strstr(uri, "://");
+	if(p == nil)
+		snprint(proto, Nproto, "ssh");
+	else if(strncmp(uri, "git+", 4) == 0)
+		grab(proto, Nproto, uri + 4, p);
+	else
+		grab(proto, Nproto, uri, p);
+	*port = 0;
+	hasport = 1;
+	if(strcmp(proto, "git") == 0)
+		snprint(port, Nport, "9418");
+	else if(strncmp(proto, "https", 5) == 0)
+		snprint(port, Nport, "443");
+	else if(strncmp(proto, "http", 4) == 0)
+		snprint(port, Nport, "80");
+	else if(strncmp(proto, "hjgit", 5) == 0)
+		snprint(port, Nport, "17021");
+	else if(strncmp(proto, "gits", 5) == 0)
+		snprint(port, Nport, "9419");
+	else
+		hasport = 0;
+	s = (p != nil) ? p + 3 : uri;
+	p = nil;
+	if(!hasport){
+		p = strstr(s, ":");
+		if(p != nil)
+			p++;
+	}
+	if(p == nil)
+		p = strstr(s, "/");
+	if(p == nil || strlen(p) == 1){
+		werrstr("missing path");
+		return -1;
+	}
+
+	q = memchr(s, ':', p - s);
+	if(q){
+		grab(host, Nhost, s, q);
+		grab(port, Nport, q + 1, p);
+	}else{
+		grab(host, Nhost, s, p);
+	}
+	
+	snprint(path, Npath, "%s", p);
+	if((q = strrchr(p, '/')) != nil)
+		p = q + 1;
+	if(strlen(p) == 0){
+		werrstr("missing repository in uri");
+		return -1;
+	}
+	n = strlen(p);
+	if(hassuffix(p, ".git"))
+		n -= 4;
+	grab(repo, Nrepo, p, p + n);
+	return 0;
+}
+
+static int
+webclone(Conn *c, char *url)
+{
+	char buf[16];
+	int n, conn;
+
+	if((c->cfd = open("/mnt/web/clone", ORDWR)) < 0)
+		goto err;
+	if((n = read(c->cfd, buf, sizeof(buf)-1)) == -1)
+		goto err;
+	buf[n] = 0;
+	conn = atoi(buf);
+
+	/* github will behave differently based on useragent */
+	if(write(c->cfd, Useragent, sizeof(Useragent)) == -1)
+		return -1;
+	dprint(1, "open url %s\n", url);
+	if(fprint(c->cfd, "url %s", url) == -1)
+		goto err;
+	free(c->dir);
+	c->dir = smprint("/mnt/web/%d", conn);
+	return 0;
+err:
+	if(c->cfd != -1)
+		close(c->cfd);
+	return -1;
+}
+
+static int
+webopen(Conn *c, char *file, int mode)
+{
+	char path[128];
+	int fd;
+
+	snprint(path, sizeof(path), "%s/%s", c->dir, file);
+	if((fd = open(path, mode)) == -1)
+		return -1;
+	return fd;
+}
+
+static int
+issmarthttp(Conn *c, char *direction)
+{
+	char buf[Pktmax+1], svc[128];
+	int n;
+
+	if((n = readpkt(c, buf, sizeof(buf))) == -1)
+		sysfatal("http read: %r");
+	buf[n] = 0;
+	snprint(svc, sizeof(svc), "# service=git-%s-pack\n", direction);
+	if(strncmp(svc, buf, n) != 0){
+		werrstr("dumb http protocol not supported");
+		return -1;
+	}
+	if(readpkt(c, buf, sizeof(buf)) != 0){
+		werrstr("protocol garble: expected flushpkt");
+		return -1;
+	}
+	return 0;
+}
+
+static int
+dialhttp(Conn *c, char *host, char *port, char *path, char *direction)
+{
+	char *geturl, *suff, *hsep, *psep;
+
+	suff = "";
+	hsep = "";
+	psep = "";
+	if(port && strlen(port) != 0)
+		hsep = ":";
+	if(path && path[0] != '/')
+		psep = "/";
+	memset(c, 0, sizeof(*c));
+	geturl = smprint("https://%s%s%s%s%s%s/info/refs?service=git-%s-pack", host, hsep, port, psep, path, suff, direction);
+	c->type = ConnHttp;
+	c->url = smprint("https://%s%s%s%s%s%s/git-%s-pack", host, hsep, port, psep, path, suff, direction);
+	c->cfd = webclone(c, geturl);
+	free(geturl);
+	if(c->cfd == -1)
+		return -1;
+	c->rfd = webopen(c, "body", OREAD);
+	c->wfd = -1;
+	if(c->rfd == -1)
+		return -1;
+	if(issmarthttp(c, direction) == -1)
+		return -1;
+	c->direction = estrdup(direction);
+	return 0;
+}
+
+static int
+dialssh(Conn *c, char *host, char *, char *path, char *direction)
+{
+	int pid, pfd[2];
+	char cmd[64];
+
+	if(pipe(pfd) == -1)
+		sysfatal("unable to open pipe: %r");
+	pid = fork();
+	if(pid == -1)
+		sysfatal("unable to fork");
+	if(pid == 0){
+		close(pfd[1]);
+		dup(pfd[0], 0);
+		dup(pfd[0], 1);
+		snprint(cmd, sizeof(cmd), "git-%s-pack", direction);
+		dprint(1, "exec ssh '%s' '%s' %s\n", host, cmd, path);
+		execl("/bin/ssh", "ssh", host, cmd, path, nil);
+	}else{
+		close(pfd[0]);
+		c->type = ConnSsh;
+		c->rfd = pfd[1];
+		c->wfd = dup(pfd[1], -1);
+	}
+	return 0;
+}
+
+static int
+dialhjgit(Conn *c, char *host, char *port, char *path, char *direction, int auth)
+{
+	char *ds, *p, *e, cmd[512];
+	int pid, pfd[2];
+
+	if((ds = netmkaddr(host, "tcp", port)) == nil)
+		return -1;
+	if(pipe(pfd) == -1)
+		sysfatal("unable to open pipe: %r");
+	pid = fork();
+	if(pid == -1)
+		sysfatal("unable to fork");
+	if(pid == 0){
+		close(pfd[1]);
+		dup(pfd[0], 0);
+		dup(pfd[0], 1);
+		dprint(1, "exec tlsclient -a %s\n", ds);
+		if(auth)
+			execl("/bin/tlsclient", "tlsclient", "-a", ds, nil);
+		else
+			execl("/bin/tlsclient", "tlsclient", ds, nil);
+		sysfatal("exec: %r");
+	}else{
+		close(pfd[0]);
+		p = cmd;
+		e = cmd + sizeof(cmd);
+		p = seprint(p, e - 1, "git-%s-pack %s", direction, path);
+		p = seprint(p + 1, e, "host=%s", host);
+		c->type = ConnGit9;
+		c->rfd = pfd[1];
+		c->wfd = dup(pfd[1], -1);
+		if(writepkt(c, cmd, p - cmd + 1) == -1){
+			fprint(2, "failed to write message\n");
+			close(c->rfd);
+			close(c->wfd);
+			return -1;
+		}
+	}
+	return 0;
+}
+
+
+static int
+dialgit(Conn *c, char *host, char *port, char *path, char *direction)
+{
+	char *ds, *p, *e, cmd[512];
+	int fd;
+
+	if((ds = netmkaddr(host, "tcp", port)) == nil)
+		return -1;
+	dprint(1, "dial %s git-%s-pack %s\n", ds, direction, path);
+	fd = dial(ds, nil, nil, nil);
+	if(fd == -1)
+		return -1;
+	p = cmd;
+	e = cmd + sizeof(cmd);
+	p = seprint(p, e - 1, "git-%s-pack %s", direction, path);
+	p = seprint(p + 1, e, "host=%s", host);
+	c->type = ConnGit;
+	c->rfd = fd;
+	c->wfd = dup(fd, -1);
+	if(writepkt(c, cmd, p - cmd + 1) == -1){
+		fprint(2, "failed to write message\n");
+		close(fd);
+		return -1;
+	}
+	return 0;
+}
+
+void
+initconn(Conn *c, int rd, int wr)
+{
+	c->type = ConnGit;
+	c->rfd = rd;
+	c->wfd = wr;
+}
+
+int
+gitconnect(Conn *c, char *uri, char *direction)
+{
+	char proto[Nproto], host[Nhost], port[Nport];
+	char repo[Nrepo], path[Npath];
+
+	if(parseuri(uri, proto, host, port, path, repo) == -1){
+		werrstr("bad uri %s", uri);
+		return -1;
+	}
+
+	memset(c, 0, sizeof(Conn));
+	if(strcmp(proto, "ssh") == 0)
+		return dialssh(c, host, port, path, direction);
+	else if(strcmp(proto, "git") == 0)
+		return dialgit(c, host, port, path, direction);
+	else if(strcmp(proto, "hjgit") == 0)
+		return dialhjgit(c, host, port, path, direction, 1);
+	else if(strcmp(proto, "gits") == 0)
+		return dialhjgit(c, host, port, path, direction, 0);
+	else if(strcmp(proto, "http") == 0 || strcmp(proto, "https") == 0)
+		return dialhttp(c, host, port, path, direction);
+	werrstr("unknown protocol %s", proto);
+	return -1;
+}
+
+int
+writephase(Conn *c)
+{
+	char hdr[128];
+	int n;
+
+	dprint(1, "start write phase\n");
+	if(c->type != ConnHttp)
+		return 0;
+
+	if(c->wfd != -1)
+		close(c->wfd);
+	if(c->cfd != -1)
+		close(c->cfd);
+	if((c->cfd = webclone(c, c->url)) == -1)
+		return -1;
+	n = snprint(hdr, sizeof(hdr), Contenthdr, c->direction);
+	if(write(c->cfd, hdr, n) == -1)
+		return -1;
+	n = snprint(hdr, sizeof(hdr), Accepthdr, c->direction);
+	if(write(c->cfd, hdr, n) == -1)
+		return -1;
+	if((c->wfd = webopen(c, "postbody", OWRITE)) == -1)
+		return -1;
+	c->rfd = -1;
+	return 0;
+}
+
+int
+readphase(Conn *c)
+{
+	dprint(1, "start read phase\n");
+	if(c->type != ConnHttp)
+		return 0;
+	if(close(c->wfd) == -1)
+		return -1;
+	if((c->rfd = webopen(c, "body", OREAD)) == -1)
+		return -1;
+	c->wfd = -1;
+	return 0;
+}
+
+void
+closeconn(Conn *c)
+{
+	close(c->rfd);
+	close(c->wfd);
+	switch(c->type){
+	case ConnGit:
+		break;
+	case ConnGit9:
+	case ConnSsh:
+		free(wait());
+		break;
+	case ConnHttp:
+		close(c->cfd);
+		break;
+	}
+}