Add ets:update_counter

CHANGELOG.md

@@ -25,6 +25,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Added the ability to run beams from the CLI for Generic Unix platform (it was already possible with nodejs and emscripten).
 - Added support for 'erlang:--/2'.
+- Added support for list insertion in 'ets:insert/2'.
+- Added support for list insertion in 'ets:update_counter/3' and 'ets:update_counter/4'.
 
 ### Fixed
 

libs/estdlib/src/ets.erl

@@ -29,7 +29,9 @@
     insert/2,
     lookup/2,
     lookup_element/3,
-    delete/2
+    delete/2,
+    update_counter/3,
+    update_counter/4
 ]).
 
 -export_type([
@@ -63,7 +65,7 @@ new(_Name, _Options) ->
 %% @doc Insert an entry into an ets table.
 %% @end
 %%-----------------------------------------------------------------------------
--spec insert(Table :: table(), Entry :: tuple()) -> true.
+-spec insert(Table :: table(), Entry :: tuple() | [tuple()]) -> true.
 insert(_Table, _Entry) ->
     erlang:nif_error(undefined).
 
@@ -101,3 +103,41 @@ lookup_element(_Table, _Key, _Pos) ->
 -spec delete(Table :: table(), Key :: term()) -> true.
 delete(_Table, _Key) ->
     erlang:nif_error(undefined).
+
+%%-----------------------------------------------------------------------------
+%% @param   Table a reference to the ets table
+%% @param   Key the key used to look up the entry expecting to contain a tuple of integers or a single integer
+%% @param   Params the increment value or a tuple {Pos, Increment} or {Pos, Increment, Treshold, SetValue},
+%%         where Pos is an integer (1-based index) specifying the position in the tuple to increment. Value is clamped to SetValue if it exceeds Threshold after update.
+%% @returns the updated element's value after performing the increment, or the default value if applicable
+%% @doc Updates a counter value at Key in the table. If Params is a single integer, it increments the direct integer value at Key or the first integer in a tuple. If Params is a tuple {Pos, Increment}, it increments the integer at the specified position Pos in the tuple stored at Key.
+%% @end
+%%-----------------------------------------------------------------------------
+-spec update_counter(
+    Table :: table(),
+    Key :: term(),
+    Params ::
+        integer() | {pos_integer(), integer()} | {pos_integer(), integer(), integer(), integer()}
+) -> integer().
+update_counter(_Table, _Key, _Params) ->
+    erlang:nif_error(undefined).
+
+%%-----------------------------------------------------------------------------
+%% @param   Table a reference to the ets table
+%% @param   Key the key used to look up the entry expecting to contain a tuple of integers or a single integer
+%% @param   Params the increment value or a tuple {Pos, Increment} or {Pos, Increment, Treshold, SetValue},
+%%         where Pos is an integer (1-based index) specifying the position in the tuple to increment. If after incrementation value exceeds the Treshold, it is set to SetValue.
+%% @param   Default the default value used if the entry at Key doesn't exist or doesn't contain a valid tuple with a sufficient size or integer at Pos
+%% @returns the updated element's value after performing the increment, or the default value if applicable
+%% @doc Updates a counter value at Key in the table. If Params is a single integer, it increments the direct integer value at Key or the first integer in a tuple. If Params is a tuple {Pos, Increment}, it increments the integer at the specified position Pos in the tuple stored at Key. If the needed element does not exist, uses Default value as a fallback.
+%% @end
+%%-----------------------------------------------------------------------------
+-spec update_counter(
+    Table :: table(),
+    Key :: term(),
+    Params ::
+        integer() | {pos_integer(), integer()} | {pos_integer(), integer(), integer(), integer()},
+    Default :: integer()
+) -> integer().
+update_counter(_Table, _Key, _Params, _Default) ->
+    erlang:nif_error(undefined).

src/libAtomVM/ets.c

@@ -25,6 +25,7 @@
 #include "ets_hashtable.h"
 #include "list.h"
 #include "memory.h"
+#include "overflow_helpers.h"
 #include "term.h"
 
 #ifndef AVM_NO_SMP
@@ -252,15 +253,9 @@ static void ets_delete_all_tables(struct Ets *ets, GlobalContext *global)
     ets_delete_tables_internal(ets, true_pred, NULL, global);
 }
 
-EtsErrorCode ets_insert(term ref, term entry, Context *ctx)
+static EtsErrorCode ets_table_insert(struct EtsTable *ets_table, term entry, Context *ctx)
 {
-    struct EtsTable *ets_table = term_is_atom(ref) ? ets_get_table_by_name(&ctx->global->ets, ref, TableAccessWrite) : ets_get_table_by_ref(&ctx->global->ets, term_to_ref_ticks(ref), TableAccessWrite);
-    if (ets_table == NULL) {
-        return EtsTableNotFound;
-    }
-
     if (ets_table->access_type != EtsAccessPublic && ets_table->owner_process_id != ctx->process_id) {
-        SMP_UNLOCK(ets_table);
         return EtsPermissionDenied;
     }
 
@@ -271,39 +266,79 @@ EtsErrorCode ets_insert(term ref, term entry, Context *ctx)
 
     Heap *heap = malloc(sizeof(Heap));
     if (IS_NULL_PTR(heap)) {
-        SMP_UNLOCK(ets_table);
         return EtsAllocationFailure;
     }
     size_t size = (size_t) memory_estimate_usage(entry);
     if (memory_init_heap(heap, size) != MEMORY_GC_OK) {
         free(heap);
-        SMP_UNLOCK(ets_table);
         return EtsAllocationFailure;
     }
 
     term new_entry = memory_copy_term_tree(heap, entry);
     term key = term_get_tuple_element(new_entry, (int) ets_table->keypos);
 
-    EtsErrorCode ret = EtsOk;
+    EtsErrorCode result = EtsOk;
     EtsHashtableErrorCode res = ets_hashtable_insert(ets_table->hashtable, key, new_entry, EtsHashtableAllowOverwrite, heap, ctx->global);
     if (UNLIKELY(res != EtsHashtableOk)) {
-        ret = EtsAllocationFailure;
+        result = EtsAllocationFailure;
     }
 
-    SMP_UNLOCK(ets_table);
+    return result;
+}
 
-    return ret;
+static EtsErrorCode ets_table_insert_list(struct EtsTable *ets_table, term list, Context *ctx)
+{
+    term list1 = list;
+
+    while (term_is_nonempty_list(list1)) {
+        term tuple = term_get_list_head(list1);
+        list1 = term_get_list_tail(list1);
+        if (!term_is_tuple(tuple) || term_get_tuple_arity(tuple) < 1) {
+            SMP_UNLOCK(ets_table);
+            return EtsBadEntry;
+        }
+    }
+    if (!term_is_nil(list1)) {
+        return EtsBadEntry;
+    }
+
+    while (term_is_nonempty_list(list)) {
+        term tuple = term_get_list_head(list);
+        EtsErrorCode result = ets_table_insert(ets_table, tuple, ctx);
+        if (UNLIKELY(result != EtsOk)) {
+            AVM_ABORT(); // Abort because operation might not be atomic.
+        }
+
+        list = term_get_list_tail(list);
+    }
+
+    return EtsOk;
 }
 
-EtsErrorCode ets_lookup(term ref, term key, term *ret, Context *ctx)
+EtsErrorCode ets_insert(term name_or_ref, term entry, Context *ctx)
 {
-    struct EtsTable *ets_table = term_is_atom(ref) ? ets_get_table_by_name(&ctx->global->ets, ref, TableAccessRead) : ets_get_table_by_ref(&ctx->global->ets, term_to_ref_ticks(ref), TableAccessRead);
+    struct EtsTable *ets_table = term_is_atom(name_or_ref) ? ets_get_table_by_name(&ctx->global->ets, name_or_ref, TableAccessWrite) : ets_get_table_by_ref(&ctx->global->ets, term_to_ref_ticks(name_or_ref), TableAccessWrite);
     if (ets_table == NULL) {
         return EtsTableNotFound;
     }
+    EtsErrorCode result;
 
+    if (term_is_tuple(entry) && term_get_tuple_arity(entry) > 0) {
+        result = ets_table_insert(ets_table, entry, ctx);
+    } else if (term_is_list(entry)) {
+        result = ets_table_insert_list(ets_table, entry, ctx);
+    } else {
+        result = EtsBadEntry;
+    }
+
+    SMP_UNLOCK(ets_table);
+
+    return result;
+}
+
+static EtsErrorCode ets_table_lookup(struct EtsTable *ets_table, term key, term *ret, Context *ctx)
+{
     if (ets_table->access_type == EtsAccessPrivate && ets_table->owner_process_id != ctx->process_id) {
-        SMP_UNLOCK(ets_table);
         return EtsPermissionDenied;
     }
 
@@ -316,24 +351,35 @@ EtsErrorCode ets_lookup(term ref, term key, term *ret, Context *ctx)
         size_t size = (size_t) memory_estimate_usage(res);
         // allocate [object]
         if (UNLIKELY(memory_ensure_free_opt(ctx, size + CONS_SIZE, MEMORY_CAN_SHRINK) != MEMORY_GC_OK)) {
-            SMP_UNLOCK(ets_table);
             return EtsAllocationFailure;
         }
         term new_res = memory_copy_term_tree(&ctx->heap, res);
         *ret = term_list_prepend(new_res, term_nil(), &ctx->heap);
     }
-    SMP_UNLOCK(ets_table);
 
     return EtsOk;
 }
 
-EtsErrorCode ets_lookup_element(term ref, term key, size_t pos, term *ret, Context *ctx)
+EtsErrorCode ets_lookup(term name_or_ref, term key, term *ret, Context *ctx)
+{
+    struct EtsTable *ets_table = term_is_atom(name_or_ref) ? ets_get_table_by_name(&ctx->global->ets, name_or_ref, TableAccessRead) : ets_get_table_by_ref(&ctx->global->ets, term_to_ref_ticks(name_or_ref), TableAccessRead);
+    if (ets_table == NULL) {
+        return EtsTableNotFound;
+    }
+
+    EtsErrorCode result = ets_table_lookup(ets_table, key, ret, ctx);
+    SMP_UNLOCK(ets_table);
+
+    return result;
+}
+
+EtsErrorCode ets_lookup_element(term name_or_ref, term key, size_t pos, term *ret, Context *ctx)
 {
     if (UNLIKELY(pos == 0)) {
         return EtsBadPosition;
     }
 
-    struct EtsTable *ets_table = term_is_atom(ref) ? ets_get_table_by_name(&ctx->global->ets, ref, TableAccessRead) : ets_get_table_by_ref(&ctx->global->ets, term_to_ref_ticks(ref), TableAccessRead);
+    struct EtsTable *ets_table = term_is_atom(name_or_ref) ? ets_get_table_by_name(&ctx->global->ets, name_or_ref, TableAccessRead) : ets_get_table_by_ref(&ctx->global->ets, term_to_ref_ticks(name_or_ref), TableAccessRead);
     if (ets_table == NULL) {
         return EtsTableNotFound;
     }
@@ -368,9 +414,9 @@ EtsErrorCode ets_lookup_element(term ref, term key, size_t pos, term *ret, Conte
     return EtsOk;
 }
 
-EtsErrorCode ets_delete(term ref, term key, term *ret, Context *ctx)
+EtsErrorCode ets_delete(term name_or_ref, term key, term *ret, Context *ctx)
 {
-    struct EtsTable *ets_table = term_is_atom(ref) ? ets_get_table_by_name(&ctx->global->ets, ref, TableAccessRead) : ets_get_table_by_ref(&ctx->global->ets, term_to_ref_ticks(ref), TableAccessRead);
+    struct EtsTable *ets_table = term_is_atom(name_or_ref) ? ets_get_table_by_name(&ctx->global->ets, name_or_ref, TableAccessRead) : ets_get_table_by_ref(&ctx->global->ets, term_to_ref_ticks(name_or_ref), TableAccessRead);
     if (ets_table == NULL) {
         return EtsTableNotFound;
     }
@@ -388,3 +434,122 @@ EtsErrorCode ets_delete(term ref, term key, term *ret, Context *ctx)
 
     return EtsOk;
 }
+
+static bool operation_to_tuple4(term operation, term *position, term *increment, term *threshold, term *set_value)
+{
+    if (term_is_integer(operation)) {
+        *increment = operation;
+        *position = term_from_int(2);
+        *threshold = term_invalid_term();
+        *set_value = term_invalid_term();
+        return true;
+    }
+
+    if (!term_is_tuple(operation)) {
+        return false;
+    }
+    int n = term_get_tuple_arity(operation);
+    if (n != 2 && n != 4) {
+        return false;
+    }
+
+    term pos = term_get_tuple_element(operation, 0);
+    term incr = term_get_tuple_element(operation, 1);
+    if (!term_is_integer(pos) || !term_is_integer(incr)) {
+        return false;
+    }
+
+    if (n == 2) {
+        *position = pos;
+        *increment = incr;
+        *threshold = term_invalid_term();
+        *set_value = term_invalid_term();
+        return true;
+    }
+
+    term tresh = term_get_tuple_element(operation, 2);
+    term set_val = term_get_tuple_element(operation, 3);
+    if (!term_is_integer(tresh) || !term_is_integer(set_val)) {
+        return false;
+    }
+
+    *position = pos;
+    *increment = incr;
+    *threshold = tresh;
+    *set_value = set_val;
+    return true;
+}
+
+EtsErrorCode ets_update_counter(term ref, term key, term operation, term default_value, term *ret, Context *ctx)
+{
+    struct EtsTable *ets_table = term_is_atom(ref) ? ets_get_table_by_name(&ctx->global->ets, ref, TableAccessWrite) : ets_get_table_by_ref(&ctx->global->ets, term_to_ref_ticks(ref), TableAccessWrite);
+    if (IS_NULL_PTR(ets_table)) {
+        return EtsTableNotFound;
+    }
+
+    term list = term_invalid_term();
+    EtsErrorCode result = ets_table_lookup(ets_table, key, &list, ctx);
+    if (result != EtsOk) {
+        SMP_UNLOCK(ets_table);
+        return result;
+    }
+
+    term to_insert;
+    if (term_is_nil(list)) {
+        if (term_is_invalid_term(default_value)) {
+            SMP_UNLOCK(ets_table);
+            return EtsBadEntry;
+        }
+        to_insert = default_value;
+    } else {
+        to_insert = term_get_list_head(list);
+    }
+
+    if (!(term_is_tuple(to_insert))) {
+        SMP_UNLOCK(ets_table);
+        return EtsBadEntry;
+    }
+    term position_term, increment_term, threshold_term, set_value_term;
+
+    if (!operation_to_tuple4(operation, &position_term, &increment_term, &threshold_term, &set_value_term)) {
+        SMP_UNLOCK(ets_table);
+        return EtsBadEntry;
+    }
+    int arity = term_get_tuple_arity(to_insert);
+    int position = term_to_int(position_term) - 1;
+    if (arity <= position || position < 1) {
+        SMP_UNLOCK(ets_table);
+        return EtsBadEntry;
+    }
+
+    term elem = term_get_tuple_element(to_insert, position);
+    if (!term_is_integer(elem)) {
+        SMP_UNLOCK(ets_table);
+        return EtsBadEntry;
+    }
+    int increment = term_to_int(increment_term);
+    int elem_value;
+    if (BUILTIN_ADD_OVERFLOW_INT(increment, term_to_int(elem), &elem_value)) {
+        SMP_UNLOCK(ets_table);
+        return EtsOverlfow;
+    }
+    if (!term_is_invalid_term(threshold_term) && !term_is_invalid_term(set_value_term)) {
+        int threshold = term_to_int(threshold_term);
+        int set_value = term_to_int(set_value_term);
+
+        if (increment >= 0 && elem_value > threshold) {
+            elem_value = set_value;
+        } else if (increment < 0 && elem_value < threshold) {
+            elem_value = set_value;
+        }
+    }
+
+    elem = term_from_int(elem_value);
+    term_put_tuple_element(to_insert, position, elem);
+    EtsErrorCode insert_result = ets_table_insert(ets_table, to_insert, ctx);
+    if (insert_result == EtsOk) {
+        *ret = elem;
+    }
+    SMP_UNLOCK(ets_table);
+    return insert_result;
+}

src/libAtomVM/ets.h

@@ -57,7 +57,8 @@ typedef enum EtsErrorCode
     EtsBadEntry,
     EtsAllocationFailure,
     EtsEntryNotFound,
-    EtsBadPosition
+    EtsBadPosition,
+    EtsOverlfow
 } EtsErrorCode;
 struct Ets
 {
@@ -77,7 +78,7 @@ EtsErrorCode ets_insert(term ref, term entry, Context *ctx);
 EtsErrorCode ets_lookup(term ref, term key, term *ret, Context *ctx);
 EtsErrorCode ets_lookup_element(term ref, term key, size_t pos, term *ret, Context *ctx);
 EtsErrorCode ets_delete(term ref, term key, term *ret, Context *ctx);
-
+EtsErrorCode ets_update_counter(term ref, term key, term value, term pos, term *ret, Context *ctx);
 #ifdef __cplusplus
 }
 #endif