Use make-image-dict and load-image-dict in thread/new

Rather than messing with janet_core_dictionary, we
instead cache the core enevironment, and pull out the
needed tables from there. This is more flexible, more correct, and
also exposes janet_resolve_core, which can be easily used from the C
API.

src/boot/boot.janet

@@ -2068,17 +2068,6 @@
   [& modules]
   ~(do ,;(map (fn [x] ~(,import* ,(string x) :prefix "")) modules)))
 
-###
-###
-### Thread Extras
-###
-###
-
-(defn thread/new
-  "Create a new thread. Same as (thread/new-ext make-image-dict load-image-dict)."
-  []
-  (thread/new-ext make-image-dict load-image-dict))
-
 ###
 ###
 ### REPL

src/core/corelib.c

@@ -983,12 +983,6 @@ static void janet_load_libs(JanetTable *env) {
 
 #ifdef JANET_BOOTSTRAP
 
-JanetTable *janet_core_dictionary(JanetTable *replacements) {
-    (void) replacements;
-    janet_panic("not defined in bootstrap");
-    return NULL;
-}
-
 JanetTable *janet_core_env(JanetTable *replacements) {
     JanetTable *env = (NULL != replacements) ? replacements : janet_table(0);
     janet_quick_asm(env, JANET_FUN_PROP,
@@ -1147,41 +1141,43 @@ JanetTable *janet_core_env(JanetTable *replacements) {
 
 #else
 
-JanetTable *janet_core_dictionary(JanetTable *replacements) {
-    JanetTable *dict;
-    if (NULL == janet_vm_core_dictionary) {
-        dict = janet_table(0);
-        janet_load_libs(dict);
-        janet_vm_core_dictionary = dict;
-        janet_gcroot(janet_wrap_table(dict));
-        /* do replacements */
-        if (NULL != replacements) {
-            for (int32_t i = 0; i < replacements->capacity; i++) {
-                if (!janet_checktype(replacements->data[i].key, JANET_NIL)) {
-                    const JanetKV *kv = replacements->data + i;
-                    janet_table_put(dict, kv->key, kv->value);
-                    if (janet_checktype(kv->value, JANET_CFUNCTION)) {
-                        janet_table_put(janet_vm_registry, kv->value, kv->key);
-                    }
+JanetTable *janet_core_env(JanetTable *replacements) {
+    /* Memoize core env, ignoring replacements the second time around. */
+    if (NULL != janet_vm_core_env) {
+        return janet_vm_core_env;
+    }
+
+    /* Load core cfunctions (and some built in janet assembly functions) */
+    JanetTable *dict = janet_table(300);
+    janet_load_libs(dict);
+
+    /* Add replacements */
+    if (replacements != NULL) {
+        for (int32_t i = 0; i < replacements->capacity; i++) {
+            JanetKV kv = replacements->data[i];
+            if (!janet_checktype(kv.key, JANET_NIL)) {
+                janet_table_put(dict, kv.key, kv.value);
+                if (janet_checktype(kv.value, JANET_CFUNCTION)) {
+                    janet_table_put(janet_vm_registry, kv.value, kv.key);
                 }
             }
         }
-    } else {
-        dict = janet_vm_core_dictionary;
     }
-    return dict;
-}
 
-JanetTable *janet_core_env(JanetTable *replacements) {
-    JanetTable *dict = janet_core_dictionary(replacements);
+    /* Unmarshal bytecode */
     Janet marsh_out = janet_unmarshal(
                           janet_core_image,
                           janet_core_image_size,
                           0,
                           dict,
                           NULL);
+
+    /* Memoize */
     janet_gcroot(marsh_out);
-    return janet_unwrap_table(marsh_out);
+    JanetTable *env = janet_unwrap_table(marsh_out);
+    janet_vm_core_env = env;
+
+    return env;
 }
 
 #endif

src/core/state.h

@@ -32,8 +32,8 @@
  * be in it. However, thread local global variables for interpreter
  * state should allow easy multi-threading. */
 
-/* The core dictionary is memoized */
-extern JANET_THREAD_LOCAL JanetTable *janet_vm_core_dictionary;
+/* Cache the core environment */
+extern JANET_THREAD_LOCAL JanetTable *janet_vm_core_env;
 
 /* How many VM stacks have been entered */
 extern JANET_THREAD_LOCAL int janet_vm_stackn;

src/core/thread.c

@@ -32,6 +32,15 @@
 #include <pthread.h>
 #include <setjmp.h>
 
+static JanetTable *janet_get_core_table(const char *name) {
+    JanetTable *env = janet_core_env(NULL);
+    Janet out = janet_wrap_nil();
+    JanetBindingType bt = janet_resolve(env, janet_csymbol(name), &out);
+    if (bt == JANET_BINDING_NONE) return NULL;
+    if (!janet_checktype(out, JANET_TABLE)) return NULL;
+    return janet_unwrap_table(out);
+}
+
 static void janet_channel_init(JanetChannel *channel, size_t initialSize) {
     janet_buffer_init(&channel->buf, (int32_t) initialSize);
     pthread_mutex_init(&channel->lock, NULL);
@@ -212,20 +221,11 @@ static int thread_worker(JanetThreadShared *shared) {
     janet_init();
 
     /* Get dictionaries */
-    JanetTable *decode = janet_core_dictionary(NULL);
-    JanetTable *encode = janet_table(decode->count);
-    for (int32_t i = 0; i < decode->capacity; i++) {
-        JanetKV *kv = decode->data + i;
-        if (!janet_checktype(kv->key, JANET_NIL)) {
-            janet_table_put(encode, kv->value, kv->key);
-        }
-    }
-    janet_gcroot(janet_wrap_table(encode));
+    JanetTable *decode = janet_get_core_table("load-image-dict");
+    JanetTable *encode = janet_get_core_table("make-image-dict");
 
     /* Create self thread */
     JanetThread *thread = janet_make_thread(shared, encode, decode, JANET_THREAD_SELF);
-    thread->encode = encode;
-    thread->decode = decode;
     Janet threadv = janet_wrap_abstract(thread);
 
     /* Unmarshal the function */
@@ -275,10 +275,14 @@ static void janet_thread_start_child(JanetThread *thread) {
  * Cfuns
  */
 
-static Janet cfun_thread_new_ext(int32_t argc, Janet *argv) {
-    janet_fixarity(argc, 2);
-    JanetTable *encode = janet_gettable(argv, 0);
-    JanetTable *decode = janet_gettable(argv, 1);
+static Janet cfun_thread_new(int32_t argc, Janet *argv) {
+    janet_arity(argc, 0, 2);
+    JanetTable *encode = (argc < 1 || janet_checktype(argv[0], JANET_NIL))
+                         ? janet_get_core_table("make-image-dict")
+                         : janet_gettable(argv, 0);
+    JanetTable *decode = (argc < 2 || janet_checktype(argv[1], JANET_NIL))
+                         ? janet_get_core_table("load-image-dict")
+                         : janet_gettable(argv, 1);
     JanetThreadShared *shared = janet_shared_create(0);
     JanetThread *thread = janet_make_thread(shared, encode, decode, JANET_THREAD_OTHER);
     janet_thread_start_child(thread);
@@ -316,8 +320,8 @@ static Janet cfun_thread_receive(int32_t argc, Janet *argv) {
 
 static const JanetReg threadlib_cfuns[] = {
     {
-        "thread/new-ext", cfun_thread_new_ext,
-        JDOC("(thread/new-ext encode-book decode-book)\n\n"
+        "thread/new", cfun_thread_new,
+        JDOC("(thread/new &opt encode-book decode-book)\n\n"
              "Start a new thread. The thread will wait for a message containing the function used to start the thread, which should be subsequently "
              "sent over after thread creation.")
     },

src/core/util.c

@@ -370,6 +370,14 @@ JanetBindingType janet_resolve(JanetTable *env, const uint8_t *sym, Janet *out)
     return JANET_BINDING_DEF;
 }
 
+/* Resolve a symbol in the core environment. */
+Janet janet_resolve_core(const char *name) {
+    JanetTable *env = janet_core_env(NULL);
+    Janet out = janet_wrap_nil();
+    janet_resolve(env, janet_csymbol(name), &out);
+    return out;
+}
+
 /* Read both tuples and arrays as c pointers + int32_t length. Return 1 if the
  * view can be constructed, 0 if an invalid type. */
 int janet_indexed_view(Janet seq, const Janet **data, int32_t *len) {

src/core/vm.c

@@ -30,7 +30,7 @@
 #endif
 
 /* VM state */
-JANET_THREAD_LOCAL JanetTable *janet_vm_core_dictionary;
+JANET_THREAD_LOCAL JanetTable *janet_vm_core_env;
 JANET_THREAD_LOCAL JanetTable *janet_vm_registry;
 JANET_THREAD_LOCAL int janet_vm_stackn = 0;
 JANET_THREAD_LOCAL JanetFiber *janet_vm_fiber = NULL;
@@ -1241,8 +1241,8 @@ int janet_init(void) {
     /* Initialize registry */
     janet_vm_registry = janet_table(0);
     janet_gcroot(janet_wrap_table(janet_vm_registry));
-    /* Core env and dictionary */
-    janet_vm_core_dictionary = NULL;
+    /* Core env */
+    janet_vm_core_env = NULL;
     /* Seed RNG */
     janet_rng_seed(janet_default_rng(), 0);
     return 0;
@@ -1257,5 +1257,5 @@ void janet_deinit(void) {
     janet_vm_root_count = 0;
     janet_vm_root_capacity = 0;
     janet_vm_registry = NULL;
-    janet_vm_core_dictionary = NULL;
+    janet_vm_core_env = NULL;
 }

src/include/janet.h

@@ -1126,7 +1126,6 @@ struct JanetCompileResult {
 JANET_API JanetCompileResult janet_compile(Janet source, JanetTable *env, const uint8_t *where);
 
 /* Get the default environment for janet */
-JANET_API JanetTable *janet_core_dictionary(JanetTable *replacements); /* Used for unmarshaling images */
 JANET_API JanetTable *janet_core_env(JanetTable *replacements);
 
 JANET_API int janet_dobytes(JanetTable *env, const uint8_t *bytes, int32_t len, const char *sourcePath, Janet *out);
@@ -1359,6 +1358,9 @@ JANET_API void janet_cfuns(JanetTable *env, const char *regprefix, const JanetRe
 JANET_API JanetBindingType janet_resolve(JanetTable *env, const uint8_t *sym, Janet *out);
 JANET_API void janet_register(const char *name, JanetCFunction cfun);
 
+/* Get values from the core environment. */
+JANET_API Janet janet_resolve_core(const char *name);
+
 /* New C API */
 
 /* Allow setting entry name for static libraries */