1. 17 Jan, 2019 2 commits
    • Jonathan Tan's avatar
      {fetch,upload}-pack: sideband v2 fetch response · 0bbc0bc5
      Jonathan Tan authored
      Currently, a response to a fetch request has sideband support only while
      the packfile is being sent, meaning that the server cannot send notices
      until the start of the packfile.
      
      Extend sideband support in protocol v2 fetch responses to the whole
      response. upload-pack will advertise it if the
      uploadpack.allowsidebandall configuration variable is set, and
      fetch-pack will automatically request it if advertised.
      
      If the sideband is to be used throughout the whole response, upload-pack
      will use it to send errors instead of prefixing a PKT-LINE payload with
      "ERR ".
      
      This will be tested in a subsequent patch.
      Signed-off-by: default avatarJonathan Tan <jonathantanmy@google.com>
      Signed-off-by: default avatarJunio C Hamano <gitster@pobox.com>
      0bbc0bc5
    • Jonathan Tan's avatar
      sideband: reverse its dependency on pkt-line · fbd76cd4
      Jonathan Tan authored
      A subsequent patch will teach struct packet_reader a new field that, if
      set, instructs it to interpret read data as multiplexed. This will
      create a dependency from pkt-line to sideband.
      
      To avoid a circular dependency, split recv_sideband() into 2 parts: the
      reading loop (left in recv_sideband()) and the processing of the
      contents (in demultiplex_sideband()), and move the former into pkt-line.
      This reverses the direction of dependency: sideband no longer depends on
      pkt-line, and pkt-line now depends on sideband.
      Signed-off-by: default avatarJonathan Tan <jonathantanmy@google.com>
      Signed-off-by: default avatarJunio C Hamano <gitster@pobox.com>
      fbd76cd4
  2. 15 Jan, 2019 1 commit
    • Jonathan Tan's avatar
      pkt-line: introduce struct packet_writer · bc2e795c
      Jonathan Tan authored
      A future patch will allow the client to request multiplexing of the
      entire fetch response (and not only during packfile transmission), which
      in turn allows the server to send progress and keepalive messages at any
      time during the response.
      
      It will be convenient for a future patch if writing options
      (specifically, whether the written data is to be multiplexed) could be
      controlled from a single place, so create struct packet_writer to serve
      as that place, and modify upload-pack to use it.
      
      Currently, it only stores the output fd, but a subsequent patch will (as
      described above) introduce an option to determine if the written data is
      to be multiplexed.
      Signed-off-by: default avatarJonathan Tan <jonathantanmy@google.com>
      Signed-off-by: default avatarJunio C Hamano <gitster@pobox.com>
      bc2e795c
  3. 02 Jan, 2019 1 commit
    • Masaya Suzuki's avatar
      pack-protocol.txt: accept error packets in any context · 2d103c31
      Masaya Suzuki authored
      In the Git pack protocol definition, an error packet may appear only in
      a certain context. However, servers can face a runtime error (e.g. I/O
      error) at an arbitrary timing. This patch changes the protocol to allow
      an error packet to be sent instead of any packet.
      
      Without this protocol spec change, when a server cannot process a
      request, there's no way to tell that to a client. Since the server
      cannot produce a valid response, it would be forced to cut a connection
      without telling why. With this protocol spec change, the server can be
      more gentle in this situation. An old client may see these error packets
      as an unexpected packet, but this is not worse than having an unexpected
      EOF.
      
      Following this protocol spec change, the error packet handling code is
      moved to pkt-line.c. Implementation wise, this implementation uses
      pkt-line to communicate with a subprocess. Since this is not a part of
      Git protocol, it's possible that a packet that is not supposed to be an
      error packet is mistakenly parsed as an error packet. This error packet
      handling is enabled only for the Git pack protocol parsing code
      considering this.
      Signed-off-by: default avatarMasaya Suzuki <masayasuzuki@google.com>
      Signed-off-by: default avatarJunio C Hamano <gitster@pobox.com>
      2d103c31
  4. 15 Mar, 2018 1 commit
  5. 14 Mar, 2018 3 commits
    • Brandon Williams's avatar
      pkt-line: add delim packet support · a4cfd41c
      Brandon Williams authored
      One of the design goals of protocol-v2 is to improve the semantics of
      flush packets.  Currently in protocol-v1, flush packets are used both to
      indicate a break in a list of packet lines as well as an indication that
      one side has finished speaking.  This makes it particularly difficult
      to implement proxies as a proxy would need to completely understand git
      protocol instead of simply looking for a flush packet.
      
      To do this, introduce the special deliminator packet '0001'.  A delim
      packet can then be used as a deliminator between lists of packet lines
      while flush packets can be reserved to indicate the end of a response.
      
      Documentation for how this packet will be used in protocol v2 will
      included in a future patch.
      Signed-off-by: default avatarBrandon Williams <bmwill@google.com>
      Signed-off-by: default avatarJunio C Hamano <gitster@pobox.com>
      a4cfd41c
    • Brandon Williams's avatar
      pkt-line: allow peeking a packet line without consuming it · 77dabc14
      Brandon Williams authored
      Sometimes it is advantageous to be able to peek the next packet line
      without consuming it (e.g. to be able to determine the protocol version
      a server is speaking).  In order to do that introduce 'struct
      packet_reader' which is an abstraction around the normal packet reading
      logic.  This enables a caller to be able to peek a single line at a time
      using 'packet_reader_peek()' and having a caller consume a line by
      calling 'packet_reader_read()'.
      Signed-off-by: default avatarBrandon Williams <bmwill@google.com>
      Signed-off-by: default avatarJunio C Hamano <gitster@pobox.com>
      77dabc14
    • Brandon Williams's avatar
      pkt-line: introduce packet_read_with_status · 2153d478
      Brandon Williams authored
      The current pkt-line API encodes the status of a pkt-line read in the
      length of the read content.  An error is indicated with '-1', a flush
      with '0' (which can be confusing since a return value of '0' can also
      indicate an empty pkt-line), and a positive integer for the length of
      the read content otherwise.  This doesn't leave much room for allowing
      the addition of additional special packets in the future.
      
      To solve this introduce 'packet_read_with_status()' which reads a packet
      and returns the status of the read encoded as an 'enum packet_status'
      type.  This allows for easily identifying between special and normal
      packets as well as errors.  It also enables easily adding a new special
      packet in the future.
      Signed-off-by: default avatarBrandon Williams <bmwill@google.com>
      Signed-off-by: default avatarJunio C Hamano <gitster@pobox.com>
      2153d478
  6. 17 Oct, 2017 1 commit
  7. 26 Jul, 2017 1 commit
    • Jonathan Tan's avatar
      sub-process: refactor handshake to common function · fa64a2fd
      Jonathan Tan authored
      Refactor, into a common function, the version and capability negotiation
      done when invoking a long-running process as a clean or smudge filter.
      This will be useful for other Git code that needs to interact similarly
      with a long-running process.
      
      As you can see in the change to t0021, this commit changes the error
      message reported when the long-running process does not introduce itself
      with the expected "server"-terminated line. Originally, the error
      message reports that the filter "does not support filter protocol
      version 2", differentiating between the old single-file filter protocol
      and the new multi-file filter protocol - I have updated it to something
      more generic and useful.
      Signed-off-by: default avatarJonathan Tan <jonathantanmy@google.com>
      Signed-off-by: default avatarJunio C Hamano <gitster@pobox.com>
      fa64a2fd
  8. 15 May, 2017 1 commit
  9. 08 May, 2017 2 commits
  10. 17 Oct, 2016 4 commits
  11. 31 Mar, 2014 1 commit
  12. 24 Feb, 2013 1 commit
    • Jeff King's avatar
      pkt-line: share buffer/descriptor reading implementation · 4981fe75
      Jeff King authored
      The packet_read function reads from a descriptor. The
      packet_get_line function is similar, but reads from an
      in-memory buffer, and uses a completely separate
      implementation. This patch teaches the generic packet_read
      function to accept either source, and we can do away with
      packet_get_line's implementation.
      
      There are two other differences to account for between the
      old and new functions. The first is that we used to read
      into a strbuf, but now read into a fixed size buffer. The
      only two callers are fine with that, and in fact it
      simplifies their code, since they can use the same
      static-buffer interface as the rest of the packet_read_line
      callers (and we provide a similar convenience wrapper for
      reading from a buffer rather than a descriptor).
      
      This is technically an externally-visible behavior change in
      that we used to accept arbitrary sized packets up to 65532
      bytes, and now cap out at LARGE_PACKET_MAX, 65520. In
      practice this doesn't matter, as we use it only for parsing
      smart-http headers (of which there is exactly one defined,
      and it is small and fixed-size). And any extension headers
      would be breaking the protocol to go over LARGE_PACKET_MAX
      anyway.
      
      The other difference is that packet_get_line would return
      on error rather than dying. However, both callers of
      packet_get_line are actually improved by dying.
      
      The first caller does its own error checking, but we can
      drop that; as a result, we'll actually get more specific
      reporting about protocol breakage when packet_read dies
      internally. The only downside is that packet_read will not
      print the smart-http URL that failed, but that's not a big
      deal; anybody not debugging can already see the remote's URL
      already, and anybody debugging would want to run with
      GIT_CURL_VERBOSE anyway to see way more information.
      
      The second caller, which is just trying to skip past any
      extra smart-http headers (of which there are none defined,
      but which we allow to keep room for future expansion), did
      not error check at all. As a result, it would treat an error
      just like a flush packet. The resulting mess would generally
      cause an error later in get_remote_heads, but now we get
      error reporting much closer to the source of the problem.
      Brown-paper-bag-fixes-by: default avatarRamsay Jones <ramsay@ramsay1.demon.co.uk>
      Signed-off-by: default avatarJeff King <peff@peff.net>
      Signed-off-by: default avatarJunio C Hamano <gitster@pobox.com>
      4981fe75
  13. 20 Feb, 2013 6 commits
    • Jeff King's avatar
      pkt-line: provide a LARGE_PACKET_MAX static buffer · 74543a04
      Jeff King authored
      Most of the callers of packet_read_line just read into a
      static 1000-byte buffer (callers which handle arbitrary
      binary data already use LARGE_PACKET_MAX). This works fine
      in practice, because:
      
        1. The only variable-sized data in these lines is a ref
           name, and refs tend to be a lot shorter than 1000
           characters.
      
        2. When sending ref lines, git-core always limits itself
           to 1000 byte packets.
      
      However, the only limit given in the protocol specification
      in Documentation/technical/protocol-common.txt is
      LARGE_PACKET_MAX; the 1000 byte limit is mentioned only in
      pack-protocol.txt, and then only describing what we write,
      not as a specific limit for readers.
      
      This patch lets us bump the 1000-byte limit to
      LARGE_PACKET_MAX. Even though git-core will never write a
      packet where this makes a difference, there are two good
      reasons to do this:
      
        1. Other git implementations may have followed
           protocol-common.txt and used a larger maximum size. We
           don't bump into it in practice because it would involve
           very long ref names.
      
        2. We may want to increase the 1000-byte limit one day.
           Since packets are transferred before any capabilities,
           it's difficult to do this in a backwards-compatible
           way. But if we bump the size of buffer the readers can
           handle, eventually older versions of git will be
           obsolete enough that we can justify bumping the
           writers, as well. We don't have plans to do this
           anytime soon, but there is no reason not to start the
           clock ticking now.
      
      Just bumping all of the reading bufs to LARGE_PACKET_MAX
      would waste memory. Instead, since most readers just read
      into a temporary buffer anyway, let's provide a single
      static buffer that all callers can use. We can further wrap
      this detail away by having the packet_read_line wrapper just
      use the buffer transparently and return a pointer to the
      static storage.  That covers most of the cases, and the
      remaining ones already read into their own LARGE_PACKET_MAX
      buffers.
      Signed-off-by: default avatarJeff King <peff@peff.net>
      Signed-off-by: default avatarJunio C Hamano <gitster@pobox.com>
      74543a04
    • Jeff King's avatar
      pkt-line: move LARGE_PACKET_MAX definition from sideband · 047ec602
      Jeff King authored
      Having the packet sizes defined near the packet read/write
      functions makes more sense.
      Signed-off-by: default avatarJeff King <peff@peff.net>
      Signed-off-by: default avatarJunio C Hamano <gitster@pobox.com>
      047ec602
    • Jeff King's avatar
      pkt-line: teach packet_read_line to chomp newlines · 819b929d
      Jeff King authored
      The packets sent during ref negotiation are all terminated
      by newline; even though the code to chomp these newlines is
      short, we end up doing it in a lot of places.
      
      This patch teaches packet_read_line to auto-chomp the
      trailing newline; this lets us get rid of a lot of inline
      chomping code.
      
      As a result, some call-sites which are not reading
      line-oriented data (e.g., when reading chunks of packfiles
      alongside sideband) transition away from packet_read_line to
      the generic packet_read interface. This patch converts all
      of the existing callsites.
      
      Since the function signature of packet_read_line does not
      change (but its behavior does), there is a possibility of
      new callsites being introduced in later commits, silently
      introducing an incompatibility.  However, since a later
      patch in this series will change the signature, such a
      commit would have to be merged directly into this commit,
      not to the tip of the series; we can therefore ignore the
      issue.
      
      This is an internal cleanup and should produce no change of
      behavior in the normal case. However, there is one corner
      case to note. Callers of packet_read_line have never been
      able to tell the difference between a flush packet ("0000")
      and an empty packet ("0004"), as both cause packet_read_line
      to return a length of 0. Readers treat them identically,
      even though Documentation/technical/protocol-common.txt says
      we must not; it also says that implementations should not
      send an empty pkt-line.
      
      By stripping out the newline before the result gets to the
      caller, we will now treat the newline-only packet ("0005\n")
      the same as an empty packet, which in turn gets treated like
      a flush packet. In practice this doesn't matter, as neither
      empty nor newline-only packets are part of git's protocols
      (at least not for the line-oriented bits, and readers who
      are not expecting line-oriented packets will be calling
      packet_read directly, anyway). But even if we do decide to
      care about the distinction later, it is orthogonal to this
      patch.  The right place to tighten would be to stop treating
      empty packets as flush packets, and this change does not
      make doing so any harder.
      Signed-off-by: default avatarJeff King <peff@peff.net>
      Signed-off-by: default avatarJunio C Hamano <gitster@pobox.com>
      819b929d
    • Jeff King's avatar
      pkt-line: provide a generic reading function with options · 03809429
      Jeff King authored
      Originally we had a single function for reading packetized
      data: packet_read_line. Commit 46284dd1 grew a more "gentle"
      form, packet_read, that returns an error instead of dying
      upon reading a truncated input stream. However, it is not
      clear from the names which should be called, or what the
      difference is.
      
      Let's instead make packet_read be a generic public interface
      that can take option flags, and update the single callsite
      that uses it. This is less code, more clear, and paves the
      way for introducing more options into the generic interface
      later. The function signature is changed, so there should be
      no hidden conflicts with topics in flight.
      
      While we're at it, we'll document how error conditions are
      handled based on the options, and rename the confusing
      "return_line_fail" option to "gentle_on_eof".  While we are
      cleaning up the names, we can drop the "return_line_fail"
      checks in packet_read_internal entirely.  They look like
      this:
      
        ret = safe_read(..., return_line_fail);
        if (return_line_fail && ret < 0)
      	  ...
      
      The check for return_line_fail is a no-op; safe_read will
      only ever return an error value if return_line_fail was true
      in the first place.
      Signed-off-by: default avatarJeff King <peff@peff.net>
      Signed-off-by: default avatarJunio C Hamano <gitster@pobox.com>
      03809429
    • Jeff King's avatar
      pkt-line: drop safe_write function · cdf4fb8e
      Jeff King authored
      This is just write_or_die by another name. The one
      distinction is that write_or_die will treat EPIPE specially
      by suppressing error messages. That's fine, as we die by
      SIGPIPE anyway (and in the off chance that it is disabled,
      write_or_die will simulate it).
      Signed-off-by: default avatarJeff King <peff@peff.net>
      Signed-off-by: default avatarJunio C Hamano <gitster@pobox.com>
      cdf4fb8e
    • Jeff King's avatar
      pkt-line: move a misplaced comment · e1485428
      Jeff King authored
      The comment describing the packet writing interface was
      originally written above packet_write, but migrated to be
      above safe_write in f3a3214e, probably because it is meant to
      generally describe the packet writing interface and not a
      single function. Let's move it into the header file, where
      users of the interface are more likely to see it.
      Signed-off-by: default avatarJeff King <peff@peff.net>
      Signed-off-by: default avatarJunio C Hamano <gitster@pobox.com>
      e1485428
  14. 19 Jun, 2012 1 commit
    • Heiko Voigt's avatar
      remove the impression of unexpectedness when access is denied · 46284dd1
      Heiko Voigt authored
      If a server accessed through ssh is denying access git will currently
      issue the message
      
      	"fatal: The remote end hung up unexpectedly"
      
      as the last line. This sounds as if something really ugly just happened.
      Since this is a quite typical situation in which users regularly get
      we do not say that if it happens at the beginning when reading the
      remote heads.
      
      If its in the very first beginning of reading the remote heads it is
      very likely an authentication error or a missing repository.
      
      If it happens later during reading the remote heads we still indicate
      that it happened during this initial contact phase.
      Signed-off-by: Heiko Voigt's avatarHeiko Voigt <hvoigt@hvoigt.net>
      Signed-off-by: default avatarJunio C Hamano <gitster@pobox.com>
      46284dd1
  15. 31 Oct, 2009 1 commit
  16. 26 Jun, 2006 1 commit
  17. 21 Jun, 2006 1 commit
  18. 10 Aug, 2005 1 commit
    • Timo Sirainen's avatar
      [PATCH] -Werror fixes · 4ec99bf0
      Timo Sirainen authored
      GCC's format __attribute__ is good for checking errors, especially
      with -Wformat=2 parameter. This fixes most of the reported problems
      against 2005-08-09 snapshot.
      4ec99bf0
  19. 30 Jun, 2005 1 commit