From: Jeff Hostetler <jeffhost@xxxxxxxxxxxxx> Teach Git to detect remote working directories on macOS and mark them as incompatible with FSMonitor. With this, `git fsmonitor--daemon run` will error out with a message like it does for bare repos. Client commands, like `git status`, will not attempt to start the daemon. Signed-off-by: Jeff Hostetler <jeffhost@xxxxxxxxxxxxx> --- compat/fsmonitor/fsm-settings-darwin.c | 66 ++++++++++++++++++++++++++ fsmonitor-settings.c | 5 ++ fsmonitor-settings.h | 1 + 3 files changed, 72 insertions(+) diff --git a/compat/fsmonitor/fsm-settings-darwin.c b/compat/fsmonitor/fsm-settings-darwin.c index 176a6f5726c..c3b719d6fb0 100644 --- a/compat/fsmonitor/fsm-settings-darwin.c +++ b/compat/fsmonitor/fsm-settings-darwin.c @@ -2,8 +2,74 @@ #include "config.h" #include "repository.h" #include "fsmonitor-settings.h" +#include "fsmonitor.h" +#include <sys/param.h> +#include <sys/mount.h> + +/* + * Remote working directories are problematic for FSMonitor. + * + * The underlying file system on the server machine and/or the remote + * mount type (NFS, SAMBA, etc.) dictates whether notification events + * are available at all to remote client machines. + * + * Kernel differences between the server and client machines also + * dictate the how (buffering, frequency, de-dup) the events are + * delivered to client machine processes. + * + * A client machine (such as a laptop) may choose to suspend/resume + * and it is unclear (without lots of testing) whether the watcher can + * resync after a resume. We might be able to treat this as a normal + * "events were dropped by the kernel" event and do our normal "flush + * and resync" --or-- we might need to close the existing (zombie?) + * notification fd and create a new one. + * + * In theory, the above issues need to be addressed whether we are + * using the Hook or IPC API. + * + * For the builtin FSMonitor, we create the Unix domain socket for the + * IPC in the .git directory. If the working directory is remote, + * then the socket will be created on the remote file system. This + * can fail if the remote file system does not support UDS file types + * (e.g. smbfs to a Windows server) or if the remote kernel does not + * allow a non-local process to bind() the socket. (These problems + * could be fixed by moving the UDS out of the .git directory and to a + * well-known local directory on the client machine, but care should + * be taken to ensure that $HOME is actually local and not a managed + * file share.) + * + * So (for now at least), mark remote working directories as + * incompatible. + */ +static enum fsmonitor_reason is_remote(struct repository *r) +{ + struct statfs fs; + + if (statfs(r->worktree, &fs) == -1) { + int saved_errno = errno; + trace_printf_key(&trace_fsmonitor, "statfs('%s') failed: %s", + r->worktree, strerror(saved_errno)); + errno = saved_errno; + return FSMONITOR_REASON_ZERO; + } + + trace_printf_key(&trace_fsmonitor, + "statfs('%s') [type 0x%08x][flags 0x%08x] '%s'", + r->worktree, fs.f_type, fs.f_flags, fs.f_fstypename); + + if (!(fs.f_flags & MNT_LOCAL)) + return FSMONITOR_REASON_REMOTE; + + return FSMONITOR_REASON_ZERO; +} enum fsmonitor_reason fsm_os__incompatible(struct repository *r) { + enum fsmonitor_reason reason; + + reason = is_remote(r); + if (reason) + return reason; + return FSMONITOR_REASON_ZERO; } diff --git a/fsmonitor-settings.c b/fsmonitor-settings.c index bb2ddd2457f..de69ace246a 100644 --- a/fsmonitor-settings.c +++ b/fsmonitor-settings.c @@ -161,6 +161,11 @@ static void create_reason_message(struct repository *r, _("virtual repos are incompatible with fsmonitor")); return; + case FSMONITOR_REASON_REMOTE: + strbuf_addstr(buf_reason, + _("remote repos are incompatible with fsmonitor")); + return; + default: BUG("Unhandled case in create_reason_message '%d'", s->reason); } diff --git a/fsmonitor-settings.h b/fsmonitor-settings.h index c169683bf2d..fca25887c0f 100644 --- a/fsmonitor-settings.h +++ b/fsmonitor-settings.h @@ -17,6 +17,7 @@ enum fsmonitor_reason { FSMONITOR_REASON_ZERO = 0, FSMONITOR_REASON_BARE = 1, FSMONITOR_REASON_VIRTUAL = 2, + FSMONITOR_REASON_REMOTE = 3, }; void fsm_settings__set_ipc(struct repository *r); -- gitgitgadget