From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-3.6 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD shortcircuit=no autolearn=ham autolearn_force=no version=3.4.0 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by dcvr.yhbt.net (Postfix) with ESMTP id A4574202A5 for ; Fri, 22 Sep 2017 00:08:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751779AbdIVAIO (ORCPT ); Thu, 21 Sep 2017 20:08:14 -0400 Received: from mail-pf0-f169.google.com ([209.85.192.169]:45899 "EHLO mail-pf0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751748AbdIVAIN (ORCPT ); Thu, 21 Sep 2017 20:08:13 -0400 Received: by mail-pf0-f169.google.com with SMTP id z84so4005909pfi.2 for ; Thu, 21 Sep 2017 17:08:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=ZxBtfAxTyU1sJBqSs9FLUqKrteT/j12Ays07yx71I6U=; b=bK9yvUW7Ktm8uet4hqf+X2PTUDTip7dblFAGq8KrLK9qfcConczQalgkDGiyeiu3jt wmLyKYkZCkUK34gJ6TC3SOa+bR0sdF04KXweaPgxBxyaxbmddWMygCfOzAnTFAqAS2As EHoSzzR0SAaiUwESiclJ1a2A4CTb4AD48drk/21KB+4r5/ho/v59Nlkl9PUqifoY4VM7 3VFlBIRxsZHtGlT2yYVjnrPjpXu40Xz8gFImGK8XamBk5sVBadwQYPPSN6qahWTd+efZ 1i8gyXX7RKb+q/O06SQEFe3rjJmliVFDIa5tpEVK3Hoi9s/rafu9r+SJwbd9n4ABzeQP mFUA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=ZxBtfAxTyU1sJBqSs9FLUqKrteT/j12Ays07yx71I6U=; b=KXwGFNoHpqJfRh8B1txTxlcRunNiHDP4qW7l8TuD96IkgW+hthtu/t6+hhoe01rqxX k/03eZkdKCuKmLweHPWxJxdwSfEm3uy3yHt0pmxdRkGj1X/jV2hWfjQS1lMMItOYgJ3f Y1R0RNE7Dh7GfHP6LhEwdFbvQleO97RiWzi86HNCAVnf9g/l2QGL5SXZ4Fgi8dji+Xj0 4DIMTKdSOOqHQw2XEDUwMgZAdw8mx+AwxpWJfupUGw9IqcWRWz2OB4IiePS6e1rYkpkY LR8JWlPOZPb4aFPiRkZ219Bx8uJ63si88+2F7yMTyxd1d9ci9O6RK+gkkodWQtGHDyjz znow== X-Gm-Message-State: AHPjjUin2WAE49KM8Je1nkrkj+FV7oPvWpKXFuV/wleF47rVx+WzO9wb lpACK6DalaO1GbHvZ0xsXF590TytSGk= X-Google-Smtp-Source: AOwi7QAfus+XGXJhYDqk6G850aSAA5DTly3Y/rjobmRp6zl4+CeJs7jtOqVzNCxmAc7BJAhFsVqgcQ== X-Received: by 10.159.198.11 with SMTP id f11mr7191268plo.290.1506038892767; Thu, 21 Sep 2017 17:08:12 -0700 (PDT) Received: from twelve2.svl.corp.google.com ([100.96.218.24]) by smtp.gmail.com with ESMTPSA id g25sm4218449pfg.166.2017.09.21.17.08.11 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Thu, 21 Sep 2017 17:08:11 -0700 (PDT) From: Jonathan Tan To: git@vger.kernel.org Cc: Jonathan Tan , jrnieder@gmail.com, gitster@pobox.com, peff@peff.net, bmwill@google.com Subject: [PATCH v3] connect: in ref advertisement, shallows are last Date: Thu, 21 Sep 2017 17:08:01 -0700 Message-Id: <20170922000801.22560-1-jonathantanmy@google.com> X-Mailer: git-send-email 2.14.1.728.g20a5b67d5.dirty In-Reply-To: <20170922000004.GB77641@google.com> References: <20170922000004.GB77641@google.com> Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Currently, get_remote_heads() parses the ref advertisement in one loop, allowing refs and shallow lines to intersperse, despite this not being allowed by the specification. Refactor get_remote_heads() to use two loops instead, enforcing that refs come first, and then shallows. This also makes it easier to teach get_remote_heads() to interpret other lines in the ref advertisement, which will be done in a subsequent patch. Signed-off-by: Jonathan Tan --- I sent the wrong version of this patch :-( This should be the correct one. A bit less clean because I introduced a 3rd state, however. connect.c | 167 +++++++++++++++++++++++++++++++++++++------------------------- 1 file changed, 101 insertions(+), 66 deletions(-) diff --git a/connect.c b/connect.c index 49b28b83b..ef6358cfc 100644 --- a/connect.c +++ b/connect.c @@ -107,6 +107,91 @@ static void annotate_refs_with_symref_info(struct ref *ref) string_list_clear(&symref, 0); } +/* + * Read one line of a server's ref advertisement into packet_buffer. + */ +static int read_remote_ref(int in, char **src_buf, size_t *src_len, + int *responded) +{ + int len = packet_read(in, src_buf, src_len, + packet_buffer, sizeof(packet_buffer), + PACKET_READ_GENTLE_ON_EOF | + PACKET_READ_CHOMP_NEWLINE); + const char *arg; + if (len < 0) + die_initial_contact(*responded); + if (len > 4 && skip_prefix(packet_buffer, "ERR ", &arg)) + die("remote error: %s", arg); + + *responded = 1; + + return len; +} + +#define EXPECTING_REF_WITH_CAPABILITIES 0 +#define EXPECTING_REF 1 +#define EXPECTING_SHALLOW 2 + +static int process_ref(int *state, int len, struct ref ***list, + unsigned int flags, struct oid_array *extra_have) +{ + struct object_id old_oid; + char *name; + int name_len; + + if (len < GIT_SHA1_HEXSZ + 2 || + get_oid_hex(packet_buffer, &old_oid) || + packet_buffer[GIT_SHA1_HEXSZ] != ' ') { + *state = EXPECTING_SHALLOW; + return 0; + } + + name = packet_buffer + GIT_SHA1_HEXSZ + 1; + name_len = strlen(name); + if (*state == EXPECTING_REF_WITH_CAPABILITIES && + len != name_len + GIT_SHA1_HEXSZ + 1) { + free(server_capabilities); + server_capabilities = xstrdup(name + name_len + 1); + } else if (*state == EXPECTING_REF) { + if (len != name_len + GIT_SHA1_HEXSZ + 1) + die("unexpected capabilities after ref name"); + } + + if (extra_have && !strcmp(name, ".have")) { + oid_array_append(extra_have, &old_oid); + } else if (!strcmp(name, "capabilities^{}")) { + if (**list) + /* cannot coexist with other refs */ + die("protocol error: unexpected capabilities^{}"); + /* There should be no more refs; proceed to the next state. */ + *state = EXPECTING_SHALLOW; + return 1; + } else if (check_ref(name, flags)) { + struct ref *ref = alloc_ref(name); + oidcpy(&ref->old_oid, &old_oid); + **list = ref; + *list = &ref->next; + } + *state = EXPECTING_REF; + return 1; +} + +static int process_shallow(struct oid_array *shallow_points) +{ + const char *arg; + struct object_id old_oid; + + if (!skip_prefix(packet_buffer, "shallow ", &arg)) + return 0; + + if (get_oid_hex(arg, &old_oid)) + die("protocol error: expected shallow sha-1, got '%s'", arg); + if (!shallow_points) + die("repository on the other end cannot be shallow"); + oid_array_append(shallow_points, &old_oid); + return 1; +} + /* * Read all the refs from the other end */ @@ -123,76 +208,26 @@ struct ref **get_remote_heads(int in, char *src_buf, size_t src_len, * willing to talk to us. A hang-up before seeing any * response does not necessarily mean an ACL problem, though. */ - int saw_response; - int got_dummy_ref_with_capabilities_declaration = 0; + int responded = 0; + int len; + int state = EXPECTING_REF_WITH_CAPABILITIES; *list = NULL; - for (saw_response = 0; ; saw_response = 1) { - struct ref *ref; - struct object_id old_oid; - char *name; - int len, name_len; - char *buffer = packet_buffer; - const char *arg; - - len = packet_read(in, &src_buf, &src_len, - packet_buffer, sizeof(packet_buffer), - PACKET_READ_GENTLE_ON_EOF | - PACKET_READ_CHOMP_NEWLINE); - if (len < 0) - die_initial_contact(saw_response); - - if (!len) - break; - - if (len > 4 && skip_prefix(buffer, "ERR ", &arg)) - die("remote error: %s", arg); - - if (len == GIT_SHA1_HEXSZ + strlen("shallow ") && - skip_prefix(buffer, "shallow ", &arg)) { - if (get_oid_hex(arg, &old_oid)) - die("protocol error: expected shallow sha-1, got '%s'", arg); - if (!shallow_points) - die("repository on the other end cannot be shallow"); - oid_array_append(shallow_points, &old_oid); - continue; - } - - if (len < GIT_SHA1_HEXSZ + 2 || get_oid_hex(buffer, &old_oid) || - buffer[GIT_SHA1_HEXSZ] != ' ') - die("protocol error: expected sha/ref, got '%s'", buffer); - name = buffer + GIT_SHA1_HEXSZ + 1; - - name_len = strlen(name); - if (len != name_len + GIT_SHA1_HEXSZ + 1) { - free(server_capabilities); - server_capabilities = xstrdup(name + name_len + 1); - } - - if (extra_have && !strcmp(name, ".have")) { - oid_array_append(extra_have, &old_oid); - continue; - } - if (!strcmp(name, "capabilities^{}")) { - if (saw_response) - die("protocol error: unexpected capabilities^{}"); - if (got_dummy_ref_with_capabilities_declaration) - die("protocol error: multiple capabilities^{}"); - got_dummy_ref_with_capabilities_declaration = 1; - continue; + while ((len = read_remote_ref(in, &src_buf, &src_len, &responded))) { + switch (state) { + case EXPECTING_REF_WITH_CAPABILITIES: + case EXPECTING_REF: + if (process_ref(&state, len, &list, flags, extra_have)) + break; + /* fallthrough */ + case EXPECTING_SHALLOW: + if (process_shallow(shallow_points)) + break; + die("protocol error: unexpected '%s'", packet_buffer); + default: + die("unexpected state %d", state); } - - if (!check_ref(name, flags)) - continue; - - if (got_dummy_ref_with_capabilities_declaration) - die("protocol error: unexpected ref after capabilities^{}"); - - ref = alloc_ref(buffer + GIT_SHA1_HEXSZ + 1); - oidcpy(&ref->old_oid, &old_oid); - *list = ref; - list = &ref->next; } annotate_refs_with_symref_info(*orig_list); -- 2.14.1.728.g20a5b67d5.dirty