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-rw-r--r--fsmonitor.c312
1 files changed, 258 insertions, 54 deletions
diff --git a/fsmonitor.c b/fsmonitor.c
index f670c50..2b17d60 100644
--- a/fsmonitor.c
+++ b/fsmonitor.c
@@ -5,6 +5,7 @@
#include "ewah/ewok.h"
#include "fsmonitor.h"
#include "fsmonitor-ipc.h"
+#include "name-hash.h"
#include "run-command.h"
#include "strbuf.h"
#include "trace2.h"
@@ -183,79 +184,282 @@ static int query_fsmonitor_hook(struct repository *r,
return result;
}
-static void fsmonitor_refresh_callback(struct index_state *istate, char *name)
+/*
+ * Invalidate the FSM bit on this CE. This is like mark_fsmonitor_invalid()
+ * but we've already handled the untracked-cache, so let's not repeat that
+ * work. This also lets us have a different trace message so that we can
+ * see everything that was done as part of the refresh-callback.
+ */
+static void invalidate_ce_fsm(struct cache_entry *ce)
{
- int i, len = strlen(name);
- int pos = index_name_pos(istate, name, len);
+ if (ce->ce_flags & CE_FSMONITOR_VALID) {
+ trace_printf_key(&trace_fsmonitor,
+ "fsmonitor_refresh_callback INV: '%s'",
+ ce->name);
+ ce->ce_flags &= ~CE_FSMONITOR_VALID;
+ }
+}
+
+static size_t handle_path_with_trailing_slash(
+ struct index_state *istate, const char *name, int pos);
+
+/*
+ * Use the name-hash to do a case-insensitive cache-entry lookup with
+ * the pathname and invalidate the cache-entry.
+ *
+ * Returns the number of cache-entries that we invalidated.
+ */
+static size_t handle_using_name_hash_icase(
+ struct index_state *istate, const char *name)
+{
+ struct cache_entry *ce = NULL;
+
+ ce = index_file_exists(istate, name, strlen(name), 1);
+ if (!ce)
+ return 0;
+ /*
+ * A case-insensitive search in the name-hash using the
+ * observed pathname found a cache-entry, so the observed path
+ * is case-incorrect. Invalidate the cache-entry and use the
+ * correct spelling from the cache-entry to invalidate the
+ * untracked-cache. Since we now have sparse-directories in
+ * the index, the observed pathname may represent a regular
+ * file or a sparse-index directory.
+ *
+ * Note that we should not have seen FSEvents for a
+ * sparse-index directory, but we handle it just in case.
+ *
+ * Either way, we know that there are not any cache-entries for
+ * children inside the cone of the directory, so we don't need to
+ * do the usual scan.
+ */
trace_printf_key(&trace_fsmonitor,
- "fsmonitor_refresh_callback '%s' (pos %d)",
- name, pos);
+ "fsmonitor_refresh_callback MAP: '%s' '%s'",
+ name, ce->name);
- if (name[len - 1] == '/') {
- /*
- * The daemon can decorate directory events, such as
- * moves or renames, with a trailing slash if the OS
- * FS Event contains sufficient information, such as
- * MacOS.
- *
- * Use this to invalidate the entire cone under that
- * directory.
- *
- * We do not expect an exact match because the index
- * does not normally contain directory entries, so we
- * start at the insertion point and scan.
- */
- if (pos < 0)
- pos = -pos - 1;
+ /*
+ * NEEDSWORK: We used the name-hash to find the correct
+ * case-spelling of the pathname in the cache-entry[], so
+ * technically this is a tracked file or a sparse-directory.
+ * It should not have any entries in the untracked-cache, so
+ * we should not need to use the case-corrected spelling to
+ * invalidate the the untracked-cache. So we may not need to
+ * do this. For now, I'm going to be conservative and always
+ * do it; we can revisit this later.
+ */
+ untracked_cache_invalidate_trimmed_path(istate, ce->name, 0);
- /* Mark all entries for the folder invalid */
- for (i = pos; i < istate->cache_nr; i++) {
- if (!starts_with(istate->cache[i]->name, name))
- break;
- istate->cache[i]->ce_flags &= ~CE_FSMONITOR_VALID;
- }
+ invalidate_ce_fsm(ce);
+ return 1;
+}
+
+/*
+ * Use the dir-name-hash to find the correct-case spelling of the
+ * directory. Use the canonical spelling to invalidate all of the
+ * cache-entries within the matching cone.
+ *
+ * Returns the number of cache-entries that we invalidated.
+ */
+static size_t handle_using_dir_name_hash_icase(
+ struct index_state *istate, const char *name)
+{
+ struct strbuf canonical_path = STRBUF_INIT;
+ int pos;
+ size_t len = strlen(name);
+ size_t nr_in_cone;
+
+ if (name[len - 1] == '/')
+ len--;
+
+ if (!index_dir_find(istate, name, len, &canonical_path))
+ return 0; /* name is untracked */
+ if (!memcmp(name, canonical_path.buf, canonical_path.len)) {
+ strbuf_release(&canonical_path);
/*
- * We need to remove the traling "/" from the path
- * for the untracked cache.
+ * NEEDSWORK: Our caller already tried an exact match
+ * and failed to find one. They called us to do an
+ * ICASE match, so we should never get an exact match,
+ * so we could promote this to a BUG() here if we
+ * wanted to. It doesn't hurt anything to just return
+ * 0 and go on because we should never get here. Or we
+ * could just get rid of the memcmp() and this "if"
+ * clause completely.
*/
- name[len - 1] = '\0';
- } else if (pos >= 0) {
+ BUG("handle_using_dir_name_hash_icase(%s) did not exact match",
+ name);
+ }
+
+ trace_printf_key(&trace_fsmonitor,
+ "fsmonitor_refresh_callback MAP: '%s' '%s'",
+ name, canonical_path.buf);
+
+ /*
+ * The dir-name-hash only tells us the corrected spelling of
+ * the prefix. We have to use this canonical path to do a
+ * lookup in the cache-entry array so that we repeat the
+ * original search using the case-corrected spelling.
+ */
+ strbuf_addch(&canonical_path, '/');
+ pos = index_name_pos(istate, canonical_path.buf,
+ canonical_path.len);
+ nr_in_cone = handle_path_with_trailing_slash(
+ istate, canonical_path.buf, pos);
+ strbuf_release(&canonical_path);
+ return nr_in_cone;
+}
+
+/*
+ * The daemon sent an observed pathname without a trailing slash.
+ * (This is the normal case.) We do not know if it is a tracked or
+ * untracked file, a sparse-directory, or a populated directory (on a
+ * platform such as Windows where FSEvents are not qualified).
+ *
+ * The pathname contains the observed case reported by the FS. We
+ * do not know it is case-correct or -incorrect.
+ *
+ * Assume it is case-correct and try an exact match.
+ *
+ * Return the number of cache-entries that we invalidated.
+ */
+static size_t handle_path_without_trailing_slash(
+ struct index_state *istate, const char *name, int pos)
+{
+ /*
+ * Mark the untracked cache dirty for this path (regardless of
+ * whether or not we find an exact match for it in the index).
+ * Since the path is unqualified (no trailing slash hint in the
+ * FSEvent), it may refer to a file or directory. So we should
+ * not assume one or the other and should always let the untracked
+ * cache decide what needs to invalidated.
+ */
+ untracked_cache_invalidate_trimmed_path(istate, name, 0);
+
+ if (pos >= 0) {
/*
- * We have an exact match for this path and can just
- * invalidate it.
+ * An exact match on a tracked file. We assume that we
+ * do not need to scan forward for a sparse-directory
+ * cache-entry with the same pathname, nor for a cone
+ * at that directory. (That is, assume no D/F conflicts.)
*/
- istate->cache[pos]->ce_flags &= ~CE_FSMONITOR_VALID;
+ invalidate_ce_fsm(istate->cache[pos]);
+ return 1;
} else {
+ size_t nr_in_cone;
+ struct strbuf work_path = STRBUF_INIT;
+
/*
- * The path is not a tracked file -or- it is a
- * directory event on a platform that cannot
- * distinguish between file and directory events in
- * the event handler, such as Windows.
- *
- * Scan as if it is a directory and invalidate the
- * cone under it. (But remember to ignore items
- * between "name" and "name/", such as "name-" and
- * "name.".
+ * The negative "pos" gives us the suggested insertion
+ * point for the pathname (without the trailing slash).
+ * We need to see if there is a directory with that
+ * prefix, but there can be lots of pathnames between
+ * "foo" and "foo/" like "foo-" or "foo-bar", so we
+ * don't want to do our own scan.
*/
+ strbuf_add(&work_path, name, strlen(name));
+ strbuf_addch(&work_path, '/');
+ pos = index_name_pos(istate, work_path.buf, work_path.len);
+ nr_in_cone = handle_path_with_trailing_slash(
+ istate, work_path.buf, pos);
+ strbuf_release(&work_path);
+ return nr_in_cone;
+ }
+}
+
+/*
+ * The daemon can decorate directory events, such as a move or rename,
+ * by adding a trailing slash to the observed name. Use this to
+ * explicitly invalidate the entire cone under that directory.
+ *
+ * The daemon can only reliably do that if the OS FSEvent contains
+ * sufficient information in the event.
+ *
+ * macOS FSEvents have enough information.
+ *
+ * Other platforms may or may not be able to do it (and it might
+ * depend on the type of event (for example, a daemon could lstat() an
+ * observed pathname after a rename, but not after a delete)).
+ *
+ * If we find an exact match in the index for a path with a trailing
+ * slash, it means that we matched a sparse-index directory in a
+ * cone-mode sparse-checkout (since that's the only time we have
+ * directories in the index). We should never see this in practice
+ * (because sparse directories should not be present and therefore
+ * not generating FS events). Either way, we can treat them in the
+ * same way and just invalidate the cache-entry and the untracked
+ * cache (and in this case, the forward cache-entry scan won't find
+ * anything and it doesn't hurt to let it run).
+ *
+ * Return the number of cache-entries that we invalidated. We will
+ * use this later to determine if we need to attempt a second
+ * case-insensitive search on case-insensitive file systems. That is,
+ * if the search using the observed-case in the FSEvent yields any
+ * results, we assume the prefix is case-correct. If there are no
+ * matches, we still don't know if the observed path is simply
+ * untracked or case-incorrect.
+ */
+static size_t handle_path_with_trailing_slash(
+ struct index_state *istate, const char *name, int pos)
+{
+ int i;
+ size_t nr_in_cone = 0;
+
+ /*
+ * Mark the untracked cache dirty for this directory path
+ * (regardless of whether or not we find an exact match for it
+ * in the index or find it to be proper prefix of one or more
+ * files in the index), since the FSEvent is hinting that
+ * there may be changes on or within the directory.
+ */
+ untracked_cache_invalidate_trimmed_path(istate, name, 0);
+
+ if (pos < 0)
pos = -pos - 1;
- for (i = pos; i < istate->cache_nr; i++) {
- if (!starts_with(istate->cache[i]->name, name))
- break;
- if ((unsigned char)istate->cache[i]->name[len] > '/')
- break;
- if (istate->cache[i]->name[len] == '/')
- istate->cache[i]->ce_flags &= ~CE_FSMONITOR_VALID;
- }
+ /* Mark all entries for the folder invalid */
+ for (i = pos; i < istate->cache_nr; i++) {
+ if (!starts_with(istate->cache[i]->name, name))
+ break;
+ invalidate_ce_fsm(istate->cache[i]);
+ nr_in_cone++;
}
+ return nr_in_cone;
+}
+
+static void fsmonitor_refresh_callback(struct index_state *istate, char *name)
+{
+ int len = strlen(name);
+ int pos = index_name_pos(istate, name, len);
+ size_t nr_in_cone;
+
+ trace_printf_key(&trace_fsmonitor,
+ "fsmonitor_refresh_callback '%s' (pos %d)",
+ name, pos);
+
+ if (name[len - 1] == '/')
+ nr_in_cone = handle_path_with_trailing_slash(istate, name, pos);
+ else
+ nr_in_cone = handle_path_without_trailing_slash(istate, name, pos);
+
/*
- * Mark the untracked cache dirty even if it wasn't found in the index
- * as it could be a new untracked file.
+ * If we did not find an exact match for this pathname or any
+ * cache-entries with this directory prefix and we're on a
+ * case-insensitive file system, try again using the name-hash
+ * and dir-name-hash.
*/
- untracked_cache_invalidate_path(istate, name, 0);
+ if (!nr_in_cone && ignore_case) {
+ nr_in_cone = handle_using_name_hash_icase(istate, name);
+ if (!nr_in_cone)
+ nr_in_cone = handle_using_dir_name_hash_icase(
+ istate, name);
+ }
+
+ if (nr_in_cone)
+ trace_printf_key(&trace_fsmonitor,
+ "fsmonitor_refresh_callback CNT: %d",
+ (int)nr_in_cone);
}
/*