fsmonitor: add assertion that fsmonitor is valid to check_removed

Validate that fsmonitor is valid to futureproof against bugs where
check_removed might be called from places that haven't refreshed.

Signed-off-by: Nipunn Koorapati <nipunn@dropbox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/diff-lib.c b/diff-lib.c
index 3fb538ad18e9934aca027a3146d58bc33d5725cc..e5a58c9259cfdfac91090e2baabd45ccf1945960 100644 (file)
--- a/diff-lib.c
+++ b/diff-lib.c
@@ -28,8 +28,9 @@
  * exists for ce that is a submodule -- it is a submodule that is not
  * checked out).  Return negative for an error.
  */
-static int check_removed(const struct cache_entry *ce, struct stat *st)
+static int check_removed(const struct index_state *istate, const struct cache_entry *ce, struct stat *st)
 {
+       assert(is_fsmonitor_refreshed(istate));
        if (!(ce->ce_flags & CE_FSMONITOR_VALID) && lstat(ce->name, st) < 0) {
                if (!is_missing_file_error(errno))
                        return -1;
@@ -136,7 +137,7 @@ int run_diff_files(struct rev_info *revs, unsigned int option)
                        memset(&(dpath->parent[0]), 0,
                               sizeof(struct combine_diff_parent)*5);
 
-                       changed = check_removed(ce, &st);
+                       changed = check_removed(istate, ce, &st);
                        if (!changed)
                                wt_mode = ce_mode_from_stat(ce, st.st_mode);
                        else {
@@ -216,7 +217,7 @@ int run_diff_files(struct rev_info *revs, unsigned int option)
                } else {
                        struct stat st;
 
-                       changed = check_removed(ce, &st);
+                       changed = check_removed(istate, ce, &st);
                        if (changed) {
                                if (changed < 0) {
                                        perror(ce->name);
@@ -278,7 +279,8 @@ static void diff_index_show_file(struct rev_info *revs,
                       oid, oid_valid, ce->name, dirty_submodule);
 }
 
-static int get_stat_data(const struct cache_entry *ce,
+static int get_stat_data(const struct index_state *istate,
+                        const struct cache_entry *ce,
                         const struct object_id **oidp,
                         unsigned int *modep,
                         int cached, int match_missing,
@@ -290,7 +292,7 @@ static int get_stat_data(const struct cache_entry *ce,
        if (!cached && !ce_uptodate(ce)) {
                int changed;
                struct stat st;
-               changed = check_removed(ce, &st);
+               changed = check_removed(istate, ce, &st);
                if (changed < 0)
                        return -1;
                else if (changed) {
@@ -321,12 +323,13 @@ static void show_new_file(struct rev_info *revs,
        const struct object_id *oid;
        unsigned int mode;
        unsigned dirty_submodule = 0;
+       struct index_state *istate = revs->diffopt.repo->index;
 
        /*
         * New file in the index: it might actually be different in
         * the working tree.
         */
-       if (get_stat_data(new_file, &oid, &mode, cached, match_missing,
+       if (get_stat_data(istate, new_file, &oid, &mode, cached, match_missing,
            &dirty_submodule, &revs->diffopt) < 0)
                return;
 
@@ -342,8 +345,9 @@ static int show_modified(struct rev_info *revs,
        unsigned int mode, oldmode;
        const struct object_id *oid;
        unsigned dirty_submodule = 0;
+       struct index_state *istate = revs->diffopt.repo->index;
 
-       if (get_stat_data(new_entry, &oid, &mode, cached, match_missing,
+       if (get_stat_data(istate, new_entry, &oid, &mode, cached, match_missing,
                          &dirty_submodule, &revs->diffopt) < 0) {
                if (report_missing)
                        diff_index_show_file(revs, "-", old_entry,

diff --git a/fsmonitor.h b/fsmonitor.h
index 7f1794b90b001cbc07991fd12e8cd7aaebe6cdfd..f20d72631d76b4b5e7d7cff75a833215a5d57a71 100644 (file)
--- a/fsmonitor.h
+++ b/fsmonitor.h
@@ -49,6 +49,17 @@ void refresh_fsmonitor(struct index_state *istate);
  */
 int fsmonitor_is_trivial_response(const struct strbuf *query_result);
 
+/*
+ * Check if refresh_fsmonitor has been called at least once.
+ * refresh_fsmonitor is idempotent. Returns true if fsmonitor is
+ * not enabled (since the state will be "fresh" w/ CE_FSMONITOR_VALID unset)
+ * This version is useful for assertions
+ */
+static inline int is_fsmonitor_refreshed(const struct index_state *istate)
+{
+       return !core_fsmonitor || istate->fsmonitor_has_run_once;
+}
+
 /*
  * Set the given cache entries CE_FSMONITOR_VALID bit. This should be
  * called any time the cache entry has been updated to reflect the