Merge pull request #21450 from zeertzjq/vim-8.2.1210

vim-patch:8.2.{1208,1209,1210}: using ht_used when looping through a hashtab is less reliable

3 files changed, 21 insertions, 15 deletions

diff --git a/src/nvim/eval/userfunc.c b/src/nvim/eval/userfunc.c
index a37613dca9..69b074ab99 100644
--- a/src/nvim/eval/userfunc.c
+++ b/src/nvim/eval/userfunc.c
@@ -1297,7 +1297,7 @@ void free_all_functions(void)
   ufunc_T *fp;
   uint64_t skipped = 0;
   uint64_t todo = 1;
-  uint64_t used;
+  int changed;
 
   // Clean up the current_funccal chain and the funccal stack.
   while (current_funccal != NULL) {
@@ -1321,9 +1321,9 @@ void free_all_functions(void)
         if (func_name_refcount((char_u *)fp->uf_name)) {
           skipped++;
         } else {
-          used = func_hashtab.ht_used;
+          changed = func_hashtab.ht_changed;
           func_clear(fp, true);
-          if (used != func_hashtab.ht_used) {
+          if (changed != func_hashtab.ht_changed) {
             skipped = 0;
             break;
           }
@@ -1993,8 +1993,8 @@ char *save_function_name(char **name, bool skip, int flags, funcdict_T *fudi)
 ///                  Otherwise functions matching "regmatch".
 static void list_functions(regmatch_T *regmatch)
 {
-  const size_t used = func_hashtab.ht_used;
-  size_t todo = used;
+  const int changed = func_hashtab.ht_changed;
+  size_t todo = func_hashtab.ht_used;
   const hashitem_T *const ht_array = func_hashtab.ht_array;
 
   for (const hashitem_T *hi = ht_array; todo > 0 && !got_int; hi++) {
@@ -2008,7 +2008,7 @@ static void list_functions(regmatch_T *regmatch)
               : (!isdigit(*fp->uf_name)
                  && vim_regexec(regmatch, (char *)fp->uf_name, 0)))) {
         list_func_head(fp, false, false);
-        if (used != func_hashtab.ht_used || ht_array != func_hashtab.ht_array) {
+        if (changed != func_hashtab.ht_changed) {
           emsg(_("E454: function list was modified"));
           return;
         }
@@ -2730,15 +2730,17 @@ bool function_exists(const char *const name, bool no_deref)
 char *get_user_func_name(expand_T *xp, int idx)
 {
   static size_t done;
+  static int changed;
   static hashitem_T *hi;
   ufunc_T *fp;
 
   if (idx == 0) {
     done = 0;
     hi = func_hashtab.ht_array;
+    changed = func_hashtab.ht_changed;
   }
   assert(hi);
-  if (done < func_hashtab.ht_used) {
+  if (changed == func_hashtab.ht_changed && done < func_hashtab.ht_used) {
     if (done++ > 0) {
       hi++;
     }
diff --git a/src/nvim/hashtab.c b/src/nvim/hashtab.c
index 31dc6f5bd4..fdbfdd7d77 100644
--- a/src/nvim/hashtab.c
+++ b/src/nvim/hashtab.c
@@ -223,6 +223,7 @@ int hash_add(hashtab_T *ht, char *key)
 void hash_add_item(hashtab_T *ht, hashitem_T *hi, char_u *key, hash_T hash)
 {
   ht->ht_used++;
+  ht->ht_changed++;
   if (hi->hi_key == NULL) {
     ht->ht_filled++;
   }
@@ -242,6 +243,7 @@ void hash_add_item(hashtab_T *ht, hashitem_T *hi, char_u *key, hash_T hash)
 void hash_remove(hashtab_T *ht, hashitem_T *hi)
 {
   ht->ht_used--;
+  ht->ht_changed++;
   hi->hi_key = HI_KEY_REMOVED;
   hash_may_resize(ht, 0);
 }
@@ -384,6 +386,7 @@ static void hash_may_resize(hashtab_T *ht, size_t minitems)
   ht->ht_array = newarray;
   ht->ht_mask = newmask;
   ht->ht_filled = ht->ht_used;
+  ht->ht_changed++;
 }
 
 #define HASH_CYCLE_BODY(hash, p) \
diff --git a/src/nvim/hashtab.h b/src/nvim/hashtab.h
index 28a3b69d44..0a50fb2ef8 100644
--- a/src/nvim/hashtab.h
+++ b/src/nvim/hashtab.h
@@ -61,14 +61,15 @@ typedef struct hashitem_S {
 ///
 /// The hashtable grows to accommodate more entries when needed.
 typedef struct hashtable_S {
-  hash_T ht_mask;               /// mask used for hash value
-                                /// (nr of items in array is "ht_mask" + 1)
-  size_t ht_used;               /// number of items used
-  size_t ht_filled;             /// number of items used or removed
-  int ht_locked;                /// counter for hash_lock()
-  hashitem_T *ht_array;         /// points to the array, allocated when it's
-                                /// not "ht_smallarray"
-  hashitem_T ht_smallarray[HT_INIT_SIZE];      /// initial array
+  hash_T ht_mask;               ///< mask used for hash value
+                                ///< (nr of items in array is "ht_mask" + 1)
+  size_t ht_used;               ///< number of items used
+  size_t ht_filled;             ///< number of items used or removed
+  int ht_changed;               ///< incremented when adding or removing an item
+  int ht_locked;                ///< counter for hash_lock()
+  hashitem_T *ht_array;         ///< points to the array, allocated when it's
+                                ///< not "ht_smallarray"
+  hashitem_T ht_smallarray[HT_INIT_SIZE];      ///< initial array
 } hashtab_T;
 
 /// Iterate over a hashtab