Adding upstream version 1:2.47.2.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

fsmonitor--daemon.h

@@ -0,0 +1,171 @@
+#ifndef FSMONITOR_DAEMON_H
+#define FSMONITOR_DAEMON_H
+
+#ifdef HAVE_FSMONITOR_DAEMON_BACKEND
+
+#include "hashmap.h"
+#include "thread-utils.h"
+#include "fsmonitor-path-utils.h"
+
+struct fsmonitor_batch;
+struct fsmonitor_token_data;
+
+/*
+ * Create a new batch of path(s).  The returned batch is considered
+ * private and not linked into the fsmonitor daemon state.  The caller
+ * should fill this batch with one or more paths and then publish it.
+ */
+struct fsmonitor_batch *fsmonitor_batch__new(void);
+
+/*
+ * Free the list of batches starting with this one.
+ */
+void fsmonitor_batch__free_list(struct fsmonitor_batch *batch);
+
+/*
+ * Add this path to this batch of modified files.
+ *
+ * The batch should be private and NOT (yet) linked into the fsmonitor
+ * daemon state and therefore not yet visible to worker threads and so
+ * no locking is required.
+ */
+void fsmonitor_batch__add_path(struct fsmonitor_batch *batch, const char *path);
+
+struct fsm_listen_data; /* opaque platform-specific data for listener thread */
+struct fsm_health_data; /* opaque platform-specific data for health thread */
+
+struct fsmonitor_daemon_state {
+	pthread_t listener_thread;
+	pthread_t health_thread;
+	pthread_mutex_t main_lock;
+
+	struct strbuf path_worktree_watch;
+	struct strbuf path_gitdir_watch;
+	struct alias_info alias;
+	int nr_paths_watching;
+
+	struct fsmonitor_token_data *current_token_data;
+
+	struct strbuf path_cookie_prefix;
+	pthread_cond_t cookies_cond;
+	int cookie_seq;
+	struct hashmap cookies;
+
+	int listen_error_code;
+	int health_error_code;
+	struct fsm_listen_data *listen_data;
+	struct fsm_health_data *health_data;
+
+	struct ipc_server_data *ipc_server_data;
+	struct strbuf path_ipc;
+
+};
+
+/*
+ * Pathname classifications.
+ *
+ * The daemon classifies the pathnames that it receives from file
+ * system notification events into the following categories and uses
+ * that to decide whether clients are told about them.  (And to watch
+ * for file system synchronization events.)
+ *
+ * The daemon only collects and reports on the set of modified paths
+ * within the working directory (proper).
+ *
+ * The client should only care about paths within the working
+ * directory proper (inside the working directory and not ".git" nor
+ * inside of ".git/").  That is, the client has read the index and is
+ * asking for a list of any paths in the working directory that have
+ * been modified since the last token.  The client does not care about
+ * file system changes within the ".git/" directory (such as new loose
+ * objects or packfiles).  So the client will only receive paths that
+ * are classified as IS_WORKDIR_PATH.
+ *
+ * Note that ".git" is usually a directory and is therefore inside
+ * the cone of the FS watch that we have on the working directory root,
+ * so we will also get FS events for disk activity on and within ".git/"
+ * that we need to respond to or filter from the client.
+ *
+ * But Git also allows ".git" to be a *file* that points to a GITDIR
+ * outside of the working directory.  When this happens, we need to
+ * create FS watches on both the working directory root *and* on the
+ * (external) GITDIR root.  (The latter is required because we put
+ * cookie files inside it and use them to sync with the FS event
+ * stream.)
+ *
+ * Note that in the context of this discussion, I'm using "GITDIR"
+ * to only mean an external GITDIR referenced by a ".git" file.
+ *
+ * The platform FS event backends will receive watch-specific
+ * relative paths (except for those OSes that always emit absolute
+ * paths).  We use the following enum and routines to classify each
+ * path so that we know how to handle it.  There is a slight asymmetry
+ * here because ".git/" is inside the working directory and the
+ * (external) GITDIR is not, and therefore how we handle events may
+ * vary slightly, so I have different enums for "IS...DOT_GIT..." and
+ * "IS...GITDIR...".
+ *
+ * The daemon uses the IS_DOT_GIT and IS_GITDIR internally to mean the
+ * exact ".git" file/directory or GITDIR directory.  If the daemon
+ * receives a delete event for either of these paths, it will
+ * automatically shutdown, for example.
+ *
+ * Note that the daemon DOES NOT explicitly watch nor special case the
+ * index.  The daemon does not read the index nor have any internal
+ * index-relative state, so there are no "IS...INDEX..." enum values.
+ */
+enum fsmonitor_path_type {
+	IS_WORKDIR_PATH = 0,
+
+	IS_DOT_GIT,
+	IS_INSIDE_DOT_GIT,
+	IS_INSIDE_DOT_GIT_WITH_COOKIE_PREFIX,
+
+	IS_GITDIR,
+	IS_INSIDE_GITDIR,
+	IS_INSIDE_GITDIR_WITH_COOKIE_PREFIX,
+
+	IS_OUTSIDE_CONE,
+};
+
+/*
+ * Classify a pathname relative to the root of the working directory.
+ */
+enum fsmonitor_path_type fsmonitor_classify_path_workdir_relative(
+	const char *relative_path);
+
+/*
+ * Classify a pathname relative to a <gitdir> that is external to the
+ * worktree directory.
+ */
+enum fsmonitor_path_type fsmonitor_classify_path_gitdir_relative(
+	const char *relative_path);
+
+/*
+ * Classify an absolute pathname received from a filesystem event.
+ */
+enum fsmonitor_path_type fsmonitor_classify_path_absolute(
+	struct fsmonitor_daemon_state *state,
+	const char *path);
+
+/*
+ * Prepend the this batch of path(s) onto the list of batches associated
+ * with the current token.  This makes the batch visible to worker threads.
+ *
+ * The caller no longer owns the batch and must not free it.
+ *
+ * Wake up the client threads waiting on these cookies.
+ */
+void fsmonitor_publish(struct fsmonitor_daemon_state *state,
+		       struct fsmonitor_batch *batch,
+		       const struct string_list *cookie_names);
+
+/*
+ * If the platform-specific layer loses sync with the filesystem,
+ * it should call this to invalidate cached data and abort waiting
+ * threads.
+ */
+void fsmonitor_force_resync(struct fsmonitor_daemon_state *state);
+
+#endif /* HAVE_FSMONITOR_DAEMON_BACKEND */
+#endif /* FSMONITOR_DAEMON_H */