WIP/RFC remote-vfs transport.

Makefile

@@ -1343,6 +1343,7 @@ ifdef NO_CURL
 	REMOTE_CURL_PRIMARY =
 	REMOTE_CURL_ALIASES =
 	REMOTE_CURL_NAMES =
+	REMOTE_VFS =
 	EXCLUDED_PROGRAMS += git-http-fetch git-http-push
 else
 	ifdef CURLDIR
@@ -1362,8 +1363,11 @@ endif
 	REMOTE_CURL_PRIMARY = git-remote-http$X
 	REMOTE_CURL_ALIASES = git-remote-https$X git-remote-ftp$X git-remote-ftps$X
 	REMOTE_CURL_NAMES = $(REMOTE_CURL_PRIMARY) $(REMOTE_CURL_ALIASES)
+	REMOTE_VFS = git-remote-vfs$X
 	PROGRAM_OBJS += http-fetch.o
 	PROGRAMS += $(REMOTE_CURL_NAMES)
+	PROGRAMS += $(REMOTE_VFS)
+	PROGRAM_OBJS += remote-vfs.o
 	curl_check := $(shell (echo 070908; $(CURL_CONFIG) --vernum | sed -e '/^70[BC]/s/^/0/') 2>/dev/null | sort -r | sed -ne 2p)
 	ifeq "$(curl_check)" "070908"
 		ifndef NO_EXPAT
@@ -2469,6 +2473,10 @@ $(REMOTE_CURL_PRIMARY): remote-curl.o http.o http-walker.o GIT-LDFLAGS $(GITLIBS
 	$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) \
 		$(CURL_LIBCURL) $(EXPAT_LIBEXPAT) $(LIBS)
 
+$(REMOTE_VFS): remote-vfs.o http.o GIT-LDFLAGS $(GITLIBS)
+	$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) \
+		$(CURL_LIBCURL) $(EXPAT_LIBEXPAT) $(LIBS)
+
 $(LIB_FILE): $(LIB_OBJS)
 	$(QUIET_AR)$(RM) $@ && $(AR) $(ARFLAGS) $@ $^
 

credential.c

@@ -372,3 +372,33 @@ void credential_from_url(struct credential *c, const char *url)
 			*p-- = '\0';
 	}
 }
+
+void credential_init_min_creds(struct credential *c,
+			       const struct credential *src)
+{
+	credential_clear(c);
+
+	/*
+	 * Set flags in a contrived way to:
+	 * () prevent "store" and "erase" calls to credential manager.
+	 * () prevent the config from being scanned.
+	 * () prevent the helpers string-list from being loaded.
+	 */
+	c->approved = 1;
+	c->configured = 1;
+
+	// TODO what to do about use_http_path?
+
+#define CP(f) do {					\
+		if (src->f && *src->f)			\
+			c->f = xstrdup(src->f);		\
+	} while (0)
+
+	CP(username);
+	CP(password);
+	CP(protocol);
+	CP(host);
+	CP(path);
+
+#undef CP
+}

credential.h

@@ -22,6 +22,9 @@ struct credential {
 void credential_init(struct credential *);
 void credential_clear(struct credential *);
 
+void credential_init_min_creds(struct credential *,
+			       const struct credential *src);
+
 void credential_fill(struct credential *);
 void credential_approve(struct credential *);
 void credential_reject(struct credential *);

http.c

@@ -475,6 +475,8 @@ static void init_curl_http_auth(CURL *result)
 	credential_fill(&http_auth);
 
 #if LIBCURL_VERSION_NUM >= 0x071301
+	trace2_printf("u:p %s %s",
+		      http_auth.username, http_auth.password);
 	curl_easy_setopt(result, CURLOPT_USERNAME, http_auth.username);
 	curl_easy_setopt(result, CURLOPT_PASSWORD, http_auth.password);
 #else
@@ -1842,7 +1844,7 @@ static void http_opt_request_remainder(CURL *curl, off_t pos)
 /* http_request() targets */
 #define HTTP_REQUEST_STRBUF	0
 #define HTTP_REQUEST_FILE	1
-
+			 
 static int http_request(const char *url,
 			void *result, int target,
 			const struct http_get_options *options)
@@ -1977,7 +1979,30 @@ static int http_request_reauth(const char *url,
 			       void *result, int target,
 			       struct http_get_options *options)
 {
-	int ret = http_request(url, result, target, options);
+	int ret;
+
+	if (options->force_vfs_creds) {
+		credential_init_min_creds(&http_auth, options->force_vfs_creds);
+
+#ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
+		/*
+		 * Turn off CURLAUTH_ANY when talking to the cache-server.
+		 * It causes the initial request to NOT send creds in order
+		 * to force the 401 and negotiate the best scheme and then
+		 * actually send the creds on the retry.
+		 *
+		 * This is problematic when talking to the cache-servers
+		 * because they send a 400 (with a "A valid Basic Auth..."
+		 * message) rather than a 401 and so the automatic retry
+		 * will never happen (and even if we do force a retry, CURL
+		 * still won't send the creds).
+		 */
+		http_auth_methods = CURLAUTH_BASIC;
+		http_auth_methods_restricted = 1;
+#endif
+	}
+
+	ret = http_request(url, result, target, options);
 
 	if (ret != HTTP_OK && ret != HTTP_REAUTH)
 		return ret;

http.h

@@ -187,6 +187,11 @@ struct http_get_options {
 	 * request has completed.
 	 */
 	struct string_list *extra_headers;
+
+	/*
+	 * TODO
+	 */
+	struct credential *force_vfs_creds;
 };
 
 /* Return values for http_get_*() */