From: Jeff Hostetler <jeffhostetler@xxxxxxxxxx>
Teach fsmonitor_refresh_callback() to handle case-insensitive
lookups if case-sensitive lookups fail on case-insensitive systems.
This can cause 'git status' to report stale status for files if there
are case issues/errors in the worktree.
The FSMonitor daemon sends FSEvents using the observed spelling
of each pathname. On case-insensitive file systems this may be
different than the expected case spelling.
The existing code uses index_name_pos() to find the cache-entry for
the pathname in the FSEvent and clear the CE_FSMONITOR_VALID bit so
that the worktree scan/index refresh will revisit and revalidate the
path.
On a case-insensitive file system, the exact match lookup may fail
to find the associated cache-entry. This causes status to think that
the cached CE flags are correct and skip over the file.
Update event handling to optionally use the name-hash and dir-name-hash
if necessary.
Signed-off-by: Jeff Hostetler <jeffhostetler@xxxxxxxxxx>
---
fsmonitor.c | 110 ++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 110 insertions(+)
diff --git a/fsmonitor.c b/fsmonitor.c
index 739ddbf7aca..ac638a61c00 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"
@@ -186,6 +187,102 @@ static int query_fsmonitor_hook(struct repository *r,
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 MAP: '%s' '%s'",
+ name, ce->name);
+
+ untracked_cache_invalidate_trimmed_path(istate, ce->name, 0);
+
+ ce->ce_flags &= ~CE_FSMONITOR_VALID;
+ 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);
+ /*
+ * 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 becaus we should never get here. Or we
+ * could just get rid of the memcmp() and this "if"
+ * clause completely.
+ */
+ return 0; /* should not happen */
+ }
+
+ 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
@@ -319,6 +416,19 @@ static void fsmonitor_refresh_callback(struct index_state *istate, char *name)
else
nr_in_cone = handle_path_without_trailing_slash(istate, name, pos);
+ /*
+ * 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.
+ */
+ 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",
--
gitgitgadget
