Update for 1.32.0

Not perfect for serialization, but a representation that
plays well with both safe integers (z where abs(z) < 2^54) and
non-integer floats.

.github/workflows/test.yml

@@ -56,7 +56,7 @@ jobs:
             gcc
       - name: Build the project
         shell: cmd
-        run: make -j CC=gcc
+        run: make -j4 CC=gcc JANET_NO_AMALG=1
 
   test-mingw-linux:
     name: Build and test with Mingw on Linux + Wine

.gitignore

@@ -34,8 +34,11 @@ local
 
 # Common test files I use.
 temp.janet
-temp*.janet
+temp.c
+temp*janet
+temp*.c
 scratch.janet
+scratch.c
 
 # Emscripten
 *.bc

CHANGELOG.md

@@ -1,7 +1,10 @@
 # Changelog
 All notable changes to this project will be documented in this file.
 
-## Unreleased - ???
+## 1.32.0 - 2023-10-14
+- Fix return value from C function `janet_dobytes` when called on Janet functions that yield to event loop.
+- Change C API for event loop interaction - get rid of JanetListener and instead use `janet_async_start` and `janet_async_end`.
+- Rework event loop to make fewer system calls on kqueue and epoll.
 - Expose atomic refcount abstraction in janet.h
 - Add `array/weak` for weak references in arrays
 - Add support for weak tables via `table/weak`, `table/weak-keys`, and `table/weak-values`.

Makefile

@@ -196,9 +196,9 @@ build/%.bin.o: src/%.c $(JANET_HEADERS) $(JANET_LOCAL_HEADERS) Makefile
 ########################
 
 ifeq ($(UNAME), Darwin)
-SONAME=libjanet.1.31.dylib
+SONAME=libjanet.1.32.dylib
 else
-SONAME=libjanet.so.1.31
+SONAME=libjanet.so.1.32
 endif
 
 build/c/shell.c: src/mainclient/shell.c

examples/posix-exec.janet

@@ -0,0 +1,5 @@
+# Switch to python
+
+(print "running in Janet")
+(os/posix-exec ["python"] :p)
+(print "will not print")

meson.build

@@ -20,7 +20,7 @@
 
 project('janet', 'c',
   default_options : ['c_std=c99', 'build.c_std=c99', 'b_lundef=false', 'default_library=both'],
-  version : '1.31.0')
+  version : '1.32.0')
 
 # Global settings
 janet_path = join_paths(get_option('prefix'), get_option('libdir'), 'janet')

src/conf/janetconf.h

@@ -4,10 +4,10 @@
 #define JANETCONF_H
 
 #define JANET_VERSION_MAJOR 1
-#define JANET_VERSION_MINOR 31
+#define JANET_VERSION_MINOR 32
 #define JANET_VERSION_PATCH 0
 #define JANET_VERSION_EXTRA ""
-#define JANET_VERSION "1.31.0"
+#define JANET_VERSION "1.32.0"
 
 /* #define JANET_BUILD "local" */
 

src/core/capi.c

@@ -338,7 +338,7 @@ int32_t janet_gethalfrange(const Janet *argv, int32_t n, int32_t length, const c
     int32_t not_raw = raw;
     if (not_raw < 0) not_raw += length + 1;
     if (not_raw < 0 || not_raw > length)
-        janet_panicf("%s index %d out of range [%d,%d]", which, raw, -length - 1, length);
+        janet_panicf("%s index %d out of range [%d,%d]", which, (int64_t) raw, -(int64_t)length - 1, (int64_t) length);
     return not_raw;
 }
 
@@ -361,7 +361,7 @@ int32_t janet_getargindex(const Janet *argv, int32_t n, int32_t length, const ch
     int32_t not_raw = raw;
     if (not_raw < 0) not_raw += length;
     if (not_raw < 0 || not_raw > length)
-        janet_panicf("%s index %d out of range [%d,%d)", which, raw, -length, length);
+        janet_panicf("%s index %d out of range [%d,%d)", which, (int64_t)raw, -(int64_t)length, (int64_t)length);
     return not_raw;
 }
 

src/core/ev.c

@@ -255,6 +255,7 @@ static void add_timeout(JanetTimeout to) {
 
 void janet_async_end(JanetFiber *fiber) {
     if (fiber->ev_callback) {
+        fiber->ev_callback(fiber, JANET_ASYNC_EVENT_DEINIT);
         janet_gcunroot(janet_wrap_abstract(fiber->ev_stream));
         fiber->ev_callback = NULL;
         if (fiber->ev_state) {
@@ -267,7 +268,16 @@ void janet_async_end(JanetFiber *fiber) {
     }
 }
 
-void *janet_async_start(JanetFiber *fiber, JanetStream *stream, JanetAsyncMode mode, JanetEVCallback callback, size_t data_size) {
+void janet_async_in_flight(JanetFiber *fiber) {
+#ifdef JANET_WINDOWS
+    fiber->flags |= JANET_FIBER_EV_FLAG_IN_FLIGHT;
+#else
+    (void) fiber;
+#endif
+}
+
+void janet_async_start(JanetStream *stream, JanetAsyncMode mode, JanetEVCallback callback, void *state) {
+    JanetFiber *fiber = janet_vm.root_fiber;
     janet_assert(!fiber->ev_callback, "double async on fiber");
     if (mode & JANET_ASYNC_LISTEN_READ) stream->read_fiber = fiber;
     if (mode & JANET_ASYNC_LISTEN_WRITE) stream->write_fiber = fiber;
@@ -275,14 +285,9 @@ void *janet_async_start(JanetFiber *fiber, JanetStream *stream, JanetAsyncMode m
     fiber->ev_stream = stream;
     janet_ev_inc_refcount();
     janet_gcroot(janet_wrap_abstract(stream));
-    if (data_size) {
-        void *data = janet_malloc(data_size);
-        fiber->ev_state = data;
-        return data;
-    } else {
-        fiber->ev_state = NULL;
-        return NULL;
-    }
+    fiber->ev_state = state;
+    callback(fiber, JANET_ASYNC_EVENT_INIT);
+    janet_await();
 }
 
 void janet_fiber_did_resume(JanetFiber *fiber) {
@@ -2199,7 +2204,7 @@ void ev_callback_read(JanetFiber *fiber, JanetAsyncEvent event) {
         }
 
         /* fallthrough */
-        case JANET_ASYNC_EVENT_USER: {
+        case JANET_ASYNC_EVENT_INIT: {
             int32_t chunk_size = state->bytes_left > JANET_EV_CHUNKSIZE ? JANET_EV_CHUNKSIZE : state->bytes_left;
             memset(&(state->overlapped), 0, sizeof(OVERLAPPED));
             int status;
@@ -2237,7 +2242,7 @@ void ev_callback_read(JanetFiber *fiber, JanetAsyncEvent event) {
                     return;
                 }
             }
-            fiber->flags |= JANET_FIBER_EV_FLAG_IN_FLIGHT;
+            janet_async_in_flight(fiber);
         }
         break;
 #else
@@ -2253,7 +2258,7 @@ void ev_callback_read(JanetFiber *fiber, JanetAsyncEvent event) {
 
     read_more:
         case JANET_ASYNC_EVENT_HUP:
-        case JANET_ASYNC_EVENT_USER:
+        case JANET_ASYNC_EVENT_INIT:
         case JANET_ASYNC_EVENT_READ: {
             JanetBuffer *buffer = state->buf;
             int32_t bytes_left = state->bytes_left;
@@ -2332,9 +2337,8 @@ void ev_callback_read(JanetFiber *fiber, JanetAsyncEvent event) {
     }
 }
 
-static void janet_ev_read_generic(JanetStream *stream, JanetBuffer *buf, int32_t nbytes, int is_chunked, JanetReadMode mode, int flags) {
-    JanetFiber *f = janet_vm.root_fiber;
-    StateRead *state = (StateRead *) janet_async_start(f, stream, JANET_ASYNC_LISTEN_READ, ev_callback_read, sizeof(StateRead));
+static JANET_NO_RETURN void janet_ev_read_generic(JanetStream *stream, JanetBuffer *buf, int32_t nbytes, int is_chunked, JanetReadMode mode, int flags) {
+    StateRead *state = janet_malloc(sizeof(StateRead));
     state->is_chunk = is_chunked;
     state->buf = buf;
     state->bytes_left = nbytes;
@@ -2345,23 +2349,23 @@ static void janet_ev_read_generic(JanetStream *stream, JanetBuffer *buf, int32_t
 #else
     state->flags = flags;
 #endif
-    ev_callback_read(f, JANET_ASYNC_EVENT_USER);
+    janet_async_start(stream, JANET_ASYNC_LISTEN_READ, ev_callback_read, state);
 }
 
-void janet_ev_read(JanetStream *stream, JanetBuffer *buf, int32_t nbytes) {
+JANET_NO_RETURN void janet_ev_read(JanetStream *stream, JanetBuffer *buf, int32_t nbytes) {
     janet_ev_read_generic(stream, buf, nbytes, 0, JANET_ASYNC_READMODE_READ, 0);
 }
-void janet_ev_readchunk(JanetStream *stream, JanetBuffer *buf, int32_t nbytes) {
+JANET_NO_RETURN void janet_ev_readchunk(JanetStream *stream, JanetBuffer *buf, int32_t nbytes) {
     janet_ev_read_generic(stream, buf, nbytes, 1, JANET_ASYNC_READMODE_READ, 0);
 }
 #ifdef JANET_NET
-void janet_ev_recv(JanetStream *stream, JanetBuffer *buf, int32_t nbytes, int flags) {
+JANET_NO_RETURN void janet_ev_recv(JanetStream *stream, JanetBuffer *buf, int32_t nbytes, int flags) {
     janet_ev_read_generic(stream, buf, nbytes, 0, JANET_ASYNC_READMODE_RECV, flags);
 }
-void janet_ev_recvchunk(JanetStream *stream, JanetBuffer *buf, int32_t nbytes, int flags) {
+JANET_NO_RETURN void janet_ev_recvchunk(JanetStream *stream, JanetBuffer *buf, int32_t nbytes, int flags) {
     janet_ev_read_generic(stream, buf, nbytes, 1, JANET_ASYNC_READMODE_RECV, flags);
 }
-void janet_ev_recvfrom(JanetStream *stream, JanetBuffer *buf, int32_t nbytes, int flags) {
+JANET_NO_RETURN void janet_ev_recvfrom(JanetStream *stream, JanetBuffer *buf, int32_t nbytes, int flags) {
     janet_ev_read_generic(stream, buf, nbytes, 0, JANET_ASYNC_READMODE_RECVFROM, flags);
 }
 #endif
@@ -2431,7 +2435,7 @@ void ev_callback_write(JanetFiber *fiber, JanetAsyncEvent event) {
             return;
         }
         break;
-        case JANET_ASYNC_EVENT_USER: {
+        case JANET_ASYNC_EVENT_INIT: {
             /* Begin write */
             int32_t len;
             const uint8_t *bytes;
@@ -2461,7 +2465,7 @@ void ev_callback_write(JanetFiber *fiber, JanetAsyncEvent event) {
                 status = WSASendTo(sock, &state->wbuf, 1, NULL, state->flags, to, tolen, &state->overlapped, NULL);
                 if (status) {
                     if (WSA_IO_PENDING == WSAGetLastError()) {
-                        fiber->flags |= JANET_FIBER_EV_FLAG_IN_FLIGHT;
+                        janet_async_in_flight(fiber);
                     } else {
                         janet_cancel(fiber, janet_ev_lasterr());
                         janet_async_end(fiber);
@@ -2486,7 +2490,7 @@ void ev_callback_write(JanetFiber *fiber, JanetAsyncEvent event) {
                 status = WriteFile(stream->handle, bytes, len, NULL, &state->overlapped);
                 if (!status) {
                     if (ERROR_IO_PENDING == GetLastError()) {
-                        fiber->flags |= JANET_FIBER_EV_FLAG_IN_FLIGHT;
+                        janet_async_in_flight(fiber);
                     } else {
                         janet_cancel(fiber, janet_ev_lasterr());
                         janet_async_end(fiber);
@@ -2505,7 +2509,7 @@ void ev_callback_write(JanetFiber *fiber, JanetAsyncEvent event) {
             janet_cancel(fiber, janet_cstringv("stream hup"));
             janet_async_end(fiber);
             break;
-        case JANET_ASYNC_EVENT_USER:
+        case JANET_ASYNC_EVENT_INIT:
         case JANET_ASYNC_EVENT_WRITE: {
             int32_t start, len;
             const uint8_t *bytes;
@@ -2570,10 +2574,8 @@ void ev_callback_write(JanetFiber *fiber, JanetAsyncEvent event) {
     }
 }
 
-static void janet_ev_write_generic(JanetStream *stream, void *buf, void *dest_abst, JanetWriteMode mode, int is_buffer, int flags) {
-    JanetFiber *f = janet_vm.root_fiber;
-    StateWrite *state = (StateWrite *) janet_async_start(f, stream, JANET_ASYNC_LISTEN_WRITE,
-                        ev_callback_write, sizeof(StateWrite));
+static JANET_NO_RETURN void janet_ev_write_generic(JanetStream *stream, void *buf, void *dest_abst, JanetWriteMode mode, int is_buffer, int flags) {
+    StateWrite *state = janet_malloc(sizeof(StateWrite));
     state->is_buffer = is_buffer;
     state->src.buf = buf;
     state->dest_abst = dest_abst;
@@ -2584,31 +2586,31 @@ static void janet_ev_write_generic(JanetStream *stream, void *buf, void *dest_ab
     state->flags = flags;
     state->start = 0;
 #endif
-    ev_callback_write(f, JANET_ASYNC_EVENT_USER);
+    janet_async_start(stream, JANET_ASYNC_LISTEN_WRITE, ev_callback_write, state);
 }
 
-void janet_ev_write_buffer(JanetStream *stream, JanetBuffer *buf) {
+JANET_NO_RETURN void janet_ev_write_buffer(JanetStream *stream, JanetBuffer *buf) {
     janet_ev_write_generic(stream, buf, NULL, JANET_ASYNC_WRITEMODE_WRITE, 1, 0);
 }
 
-void janet_ev_write_string(JanetStream *stream, JanetString str) {
+JANET_NO_RETURN void janet_ev_write_string(JanetStream *stream, JanetString str) {
     janet_ev_write_generic(stream, (void *) str, NULL, JANET_ASYNC_WRITEMODE_WRITE, 0, 0);
 }
 
 #ifdef JANET_NET
-void janet_ev_send_buffer(JanetStream *stream, JanetBuffer *buf, int flags) {
+JANET_NO_RETURN void janet_ev_send_buffer(JanetStream *stream, JanetBuffer *buf, int flags) {
     janet_ev_write_generic(stream, buf, NULL, JANET_ASYNC_WRITEMODE_SEND, 1, flags);
 }
 
-void janet_ev_send_string(JanetStream *stream, JanetString str, int flags) {
+JANET_NO_RETURN void janet_ev_send_string(JanetStream *stream, JanetString str, int flags) {
     janet_ev_write_generic(stream, (void *) str, NULL, JANET_ASYNC_WRITEMODE_SEND, 0, flags);
 }
 
-void janet_ev_sendto_buffer(JanetStream *stream, JanetBuffer *buf, void *dest, int flags) {
+JANET_NO_RETURN void janet_ev_sendto_buffer(JanetStream *stream, JanetBuffer *buf, void *dest, int flags) {
     janet_ev_write_generic(stream, buf, dest, JANET_ASYNC_WRITEMODE_SENDTO, 1, flags);
 }
 
-void janet_ev_sendto_string(JanetStream *stream, JanetString str, void *dest, int flags) {
+JANET_NO_RETURN void janet_ev_sendto_string(JanetStream *stream, JanetString str, void *dest, int flags) {
     janet_ev_write_generic(stream, (void *) str, dest, JANET_ASYNC_WRITEMODE_SENDTO, 0, flags);
 }
 #endif
@@ -2999,7 +3001,6 @@ JANET_CORE_FN(janet_cfun_stream_read,
         if (to != INFINITY) janet_addtimeout(to);
         janet_ev_read(stream, buffer, n);
     }
-    janet_await();
 }
 
 JANET_CORE_FN(janet_cfun_stream_chunk,
@@ -3014,7 +3015,6 @@ JANET_CORE_FN(janet_cfun_stream_chunk,
     double to = janet_optnumber(argv, argc, 3, INFINITY);
     if (to != INFINITY) janet_addtimeout(to);
     janet_ev_readchunk(stream, buffer, n);
-    janet_await();
 }
 
 JANET_CORE_FN(janet_cfun_stream_write,
@@ -3034,7 +3034,6 @@ JANET_CORE_FN(janet_cfun_stream_write,
         if (to != INFINITY) janet_addtimeout(to);
         janet_ev_write_string(stream, bytes.bytes);
     }
-    janet_await();
 }
 
 static int mutexgc(void *p, size_t size) {

src/core/ffi.c

@@ -999,13 +999,13 @@ typedef struct {
     uint64_t x;
 } sysv64_sseint_return;
 typedef sysv64_int_return janet_sysv64_variant_1(uint64_t a, uint64_t b, uint64_t c, uint64_t d, uint64_t e, uint64_t f,
-        double r1, double r2, double r3, double r4, double r5, double r6, double r7, double r8);
+    double r1, double r2, double r3, double r4, double r5, double r6, double r7, double r8);
 typedef sysv64_sse_return janet_sysv64_variant_2(uint64_t a, uint64_t b, uint64_t c, uint64_t d, uint64_t e, uint64_t f,
-        double r1, double r2, double r3, double r4, double r5, double r6, double r7, double r8);
+    double r1, double r2, double r3, double r4, double r5, double r6, double r7, double r8);
 typedef sysv64_intsse_return janet_sysv64_variant_3(uint64_t a, uint64_t b, uint64_t c, uint64_t d, uint64_t e, uint64_t f,
-        double r1, double r2, double r3, double r4, double r5, double r6, double r7, double r8);
+    double r1, double r2, double r3, double r4, double r5, double r6, double r7, double r8);
 typedef sysv64_sseint_return janet_sysv64_variant_4(uint64_t a, uint64_t b, uint64_t c, uint64_t d, uint64_t e, uint64_t f,
-        double r1, double r2, double r3, double r4, double r5, double r6, double r7, double r8);
+    double r1, double r2, double r3, double r4, double r5, double r6, double r7, double r8);
 
 static Janet janet_ffi_sysv64(JanetFFISignature *signature, void *function_pointer, const Janet *argv) {
     union {

src/core/fiber.c

@@ -239,8 +239,8 @@ int janet_fiber_funcframe(JanetFiber *fiber, JanetFunction *func) {
                                          fiber->data + tuplehead,
                                          oldtop - tuplehead)
                                      : janet_wrap_tuple(janet_tuple_n(
-                                                 fiber->data + tuplehead,
-                                                 oldtop - tuplehead));
+                                             fiber->data + tuplehead,
+                                             oldtop - tuplehead));
         }
     }
 
@@ -370,8 +370,8 @@ int janet_fiber_funcframe_tail(JanetFiber *fiber, JanetFunction *func) {
                                          fiber->data + tuplehead,
                                          fiber->stacktop - tuplehead)
                                      : janet_wrap_tuple(janet_tuple_n(
-                                                 fiber->data + tuplehead,
-                                                 fiber->stacktop - tuplehead));
+                                             fiber->data + tuplehead,
+                                             fiber->stacktop - tuplehead));
         }
         stacksize = tuplehead - fiber->stackstart + 1;
     } else {

src/core/net.c

@@ -124,6 +124,13 @@ void net_callback_connect(JanetFiber *fiber, JanetAsyncEvent event) {
     switch (event) {
         default:
             break;
+#ifndef JANET_WINDOWS
+        /* Wait until we have an actually event before checking.
+         * Windows doesn't support async connect with this, just try immediately.*/
+        case JANET_ASYNC_EVENT_INIT:
+#endif
+        case JANET_ASYNC_EVENT_DEINIT:
+            return;
         case JANET_ASYNC_EVENT_CLOSE:
             janet_cancel(fiber, janet_cstringv("stream closed"));
             janet_async_end(fiber);
@@ -154,12 +161,9 @@ void net_callback_connect(JanetFiber *fiber, JanetAsyncEvent event) {
 }
 
 static void net_sched_connect(JanetStream *stream) {
-    JanetFiber *f = janet_vm.root_fiber;
-    NetStateConnect *state = (NetStateConnect *) janet_async_start(f, stream, JANET_ASYNC_LISTEN_WRITE, net_callback_connect, sizeof(NetStateConnect));
+    NetStateConnect *state = janet_malloc(sizeof(NetStateConnect));
     state->did_connect = 0;
-#ifdef JANET_WINDOWS
-    net_callback_connect(f, JANET_ASYNC_EVENT_USER);
-#endif
+    janet_async_start(stream, JANET_ASYNC_LISTEN_WRITE, net_callback_connect, state);
 }
 
 /* State machine for accepting connections. */
@@ -229,14 +233,16 @@ void net_callback_accept(JanetFiber *fiber, JanetAsyncEvent event) {
 
 JANET_NO_RETURN static void janet_sched_accept(JanetStream *stream, JanetFunction *fun) {
     Janet err;
-    JanetFiber *f = janet_vm.root_fiber;
-    NetStateAccept *state = (NetStateAccept *) janet_async_start(f, stream, JANET_ASYNC_LISTEN_READ, net_callback_accept, sizeof(NetStateAccept));
+    NetStateAccept *state = janet_malloc(sizeof(NetStateAccept));
     memset(&state->overlapped, 0, sizeof(WSAOVERLAPPED));
     memset(&state->buf, 0, 1024);
     state->function = fun;
     state->lstream = stream;
-    if (net_sched_accept_impl(state, f, &err)) janet_panicv(err);
-    janet_await();
+    if (net_sched_accept_impl(state, janet_root_fiber(), &err)) {
+        janet_free(state);
+        janet_panicv(err);
+    }
+    janet_async_start(stream, JANET_ASYNC_LISTEN_READ, net_callback_accept, state);
 }
 
 static int net_sched_accept_impl(NetStateAccept *state, JanetFiber *fiber, Janet *err) {
@@ -253,7 +259,7 @@ static int net_sched_accept_impl(NetStateAccept *state, JanetFiber *fiber, Janet
         int code = WSAGetLastError();
         if (code == WSA_IO_PENDING) {
             /* indicates io is happening async */
-            fiber->flags |= JANET_FIBER_EV_FLAG_IN_FLIGHT;
+            janet_async_in_flight(fiber);
             return 0;
         }
         *err = janet_ev_lasterr();
@@ -282,7 +288,7 @@ void net_callback_accept(JanetFiber *fiber, JanetAsyncEvent event) {
             janet_schedule(fiber, janet_wrap_nil());
             janet_async_end(fiber);
             return;
-        case JANET_ASYNC_EVENT_USER:
+        case JANET_ASYNC_EVENT_INIT:
         case JANET_ASYNC_EVENT_READ: {
 #if defined(JANET_LINUX)
             JSock connfd = accept4(stream->handle, NULL, NULL, SOCK_CLOEXEC);
@@ -310,11 +316,10 @@ void net_callback_accept(JanetFiber *fiber, JanetAsyncEvent event) {
 }
 
 JANET_NO_RETURN static void janet_sched_accept(JanetStream *stream, JanetFunction *fun) {
-    JanetFiber *f = janet_vm.root_fiber;
-    NetStateAccept *state = (NetStateAccept *) janet_async_start(f, stream, JANET_ASYNC_LISTEN_READ, net_callback_accept, sizeof(NetStateAccept));
+    NetStateAccept *state = janet_malloc(sizeof(NetStateAccept));
+    memset(state, 0, sizeof(NetStateAccept));
     state->function = fun;
-    net_callback_accept(f, JANET_ASYNC_EVENT_USER);
-    janet_await();
+    janet_async_start(stream, JANET_ASYNC_LISTEN_READ, net_callback_accept, state);
 }
 
 #endif
@@ -851,7 +856,6 @@ JANET_CORE_FN(cfun_stream_read,
         if (to != INFINITY) janet_addtimeout(to);
         janet_ev_recv(stream, buffer, n, MSG_NOSIGNAL);
     }
-    janet_await();
 }
 
 JANET_CORE_FN(cfun_stream_chunk,
@@ -866,7 +870,6 @@ JANET_CORE_FN(cfun_stream_chunk,
     double to = janet_optnumber(argv, argc, 3, INFINITY);
     if (to != INFINITY) janet_addtimeout(to);
     janet_ev_recvchunk(stream, buffer, n, MSG_NOSIGNAL);
-    janet_await();
 }
 
 JANET_CORE_FN(cfun_stream_recv_from,
@@ -881,7 +884,6 @@ JANET_CORE_FN(cfun_stream_recv_from,
     double to = janet_optnumber(argv, argc, 3, INFINITY);
     if (to != INFINITY) janet_addtimeout(to);
     janet_ev_recvfrom(stream, buffer, n, MSG_NOSIGNAL);
-    janet_await();
 }
 
 JANET_CORE_FN(cfun_stream_write,
@@ -901,7 +903,6 @@ JANET_CORE_FN(cfun_stream_write,
         if (to != INFINITY) janet_addtimeout(to);
         janet_ev_send_string(stream, bytes.bytes, MSG_NOSIGNAL);
     }
-    janet_await();
 }
 
 JANET_CORE_FN(cfun_stream_send_to,
@@ -922,7 +923,6 @@ JANET_CORE_FN(cfun_stream_send_to,
         if (to != INFINITY) janet_addtimeout(to);
         janet_ev_sendto_string(stream, bytes.bytes, dest, MSG_NOSIGNAL);
     }
-    janet_await();
 }
 
 JANET_CORE_FN(cfun_stream_flush,

src/core/os.c

@@ -1081,11 +1081,18 @@ static JanetFile *get_stdio_for_handle(JanetHandle handle, void *orig, int iswri
 }
 #endif
 
-static Janet os_execute_impl(int32_t argc, Janet *argv, int is_spawn) {
+typedef enum {
+    JANET_EXECUTE_EXECUTE,
+    JANET_EXECUTE_SPAWN,
+    JANET_EXECUTE_EXEC
+} JanetExecuteMode;
+
+static Janet os_execute_impl(int32_t argc, Janet *argv, JanetExecuteMode mode) {
     janet_sandbox_assert(JANET_SANDBOX_SUBPROCESS);
     janet_arity(argc, 1, 3);
 
     /* Get flags */
+    int is_spawn = mode == JANET_EXECUTE_SPAWN;
     uint64_t flags = 0;
     if (argc > 1) {
         flags = janet_getflags(argv, 1, "epxd");
@@ -1109,7 +1116,7 @@ static Janet os_execute_impl(int32_t argc, Janet *argv, int is_spawn) {
     int pipe_owner_flags = (is_spawn && (flags & 0x8)) ? JANET_PROC_ALLOW_ZOMBIE : 0;
 
     /* Get optional redirections */
-    if (argc > 2) {
+    if (argc > 2 && (mode != JANET_EXECUTE_EXEC)) {
         JanetDictView tab = janet_getdictionary(argv, 2);
         Janet maybe_stdin = janet_dictionary_get(tab.kvs, tab.cap, janet_ckeywordv("in"));
         Janet maybe_stdout = janet_dictionary_get(tab.kvs, tab.cap, janet_ckeywordv("out"));
@@ -1230,12 +1237,32 @@ static Janet os_execute_impl(int32_t argc, Janet *argv, int is_spawn) {
      * of posix_spawn would modify the argv array passed in. */
     char *const *cargv = (char *const *)child_argv;
 
-    /* Use posix_spawn to spawn new process */
-
     if (use_environ) {
         janet_lock_environ();
     }
 
+    /* exec mode */
+    if (mode == JANET_EXECUTE_EXEC) {
+#ifdef JANET_WINDOWS
+        janet_panic("not supported on windows");
+#else
+        int status;
+        if (!use_environ) {
+            environ = envp;
+        }
+        do {
+            if (janet_flag_at(flags, 1)) {
+                status = execvp(cargv[0], cargv);
+            } else {
+                status = execv(cargv[0], cargv);
+            }
+        } while (status == -1 && errno == EINTR);
+        janet_panicf("%p: %s", cargv[0], strerror(errno ? errno : ENOENT));
+#endif
+    }
+
+    /* Use posix_spawn to spawn new process */
+
     /* Posix spawn setup */
     posix_spawn_file_actions_t actions;
     posix_spawn_file_actions_init(&actions);
@@ -1344,7 +1371,7 @@ JANET_CORE_FN(os_execute,
               "contain the keys :in, :out, and :err, which allow redirecting stdio in the subprocess. "
               "These arguments should be core/file values. "
               "Returns the exit status of the program.") {
-    return os_execute_impl(argc, argv, 0);
+    return os_execute_impl(argc, argv, JANET_EXECUTE_EXECUTE);
 }
 
 JANET_CORE_FN(os_spawn,
@@ -1357,7 +1384,15 @@ JANET_CORE_FN(os_spawn,
               "The returned value `proc` has the fields :in, :out, :err, :return-code, and "
               "the additional field :pid on unix-like platforms. Use `(os/proc-wait proc)` to rejoin the "
               "subprocess or `(os/proc-kill proc)`.") {
-    return os_execute_impl(argc, argv, 1);
+    return os_execute_impl(argc, argv, JANET_EXECUTE_SPAWN);
+}
+
+JANET_CORE_FN(os_posix_exec,
+              "(os/posix-exec args &opt flags env)",
+              "Use the execvpe or execve system calls to replace the current process with an interface similar to os/execute. "
+              "Hoever, instead of creating a subprocess, the current process is replaced. Is not supported on windows, and "
+              "does not allow redirection of stdio.") {
+    return os_execute_impl(argc, argv, JANET_EXECUTE_EXEC);
 }
 
 #ifdef JANET_EV
@@ -2651,6 +2686,7 @@ void janet_lib_os(JanetTable *env) {
         JANET_CORE_REG("os/spawn", os_spawn),
         JANET_CORE_REG("os/shell", os_shell),
         JANET_CORE_REG("os/posix-fork", os_posix_fork),
+        JANET_CORE_REG("os/posix-exec", os_posix_exec),
         /* no need to sandbox process management if you can't create processes
          * (allows for limited functionality if use exposes C-functions to create specific processes) */
         JANET_CORE_REG("os/proc-wait", os_proc_wait),

src/core/pp.c

@@ -31,6 +31,7 @@
 #include <string.h>
 #include <ctype.h>
 #include <inttypes.h>
+#include <float.h>
 
 /* Implements a pretty printer for Janet. The pretty printer
  * is simple and not that flexible, but fast. */
@@ -38,11 +39,15 @@
 /* Temporary buffer size */
 #define BUFSIZE 64
 
+/* Preprocessor hacks */
+#define STR_HELPER(x) #x
+#define STR(x) STR_HELPER(x)
+
 static void number_to_string_b(JanetBuffer *buffer, double x) {
     janet_buffer_ensure(buffer, buffer->count + BUFSIZE, 2);
     const char *fmt = (x == floor(x) &&
                        x <= JANET_INTMAX_DOUBLE &&
-                       x >= JANET_INTMIN_DOUBLE) ? "%.0f" : "%g";
+                       x >= JANET_INTMIN_DOUBLE) ? "%.0f" : ("%." STR(DBL_DIG) "g");
     int count;
     if (x == 0.0) {
         /* Prevent printing of '-0' */
@@ -772,6 +777,8 @@ struct FmtMapping {
 /* Janet uses fixed width integer types for most things, so map
  * format specifiers to these fixed sizes */
 static const struct FmtMapping format_mappings[] = {
+    {'D', PRId64},
+    {'I', PRIi64},
     {'d', PRId64},
     {'i', PRIi64},
     {'o', PRIo64},
@@ -850,13 +857,19 @@ void janet_formatbv(JanetBuffer *b, const char *format, va_list args) {
             c = scanformat(c, form, width, precision);
             switch (*c++) {
                 case 'c': {
-                    int n = va_arg(args, long);
+                    int n = va_arg(args, int);
                     nb = snprintf(item, MAX_ITEM, form, n);
                     break;
                 }
                 case 'd':
                 case 'i': {
-                    int64_t n = va_arg(args, int);
+                    int64_t n = (int64_t) va_arg(args, int32_t);
+                    nb = snprintf(item, MAX_ITEM, form, n);
+                    break;
+                }
+                case 'D':
+                case 'I': {
+                    int64_t n = va_arg(args, int64_t);
                     nb = snprintf(item, MAX_ITEM, form, n);
                     break;
                 }
@@ -864,7 +877,7 @@ void janet_formatbv(JanetBuffer *b, const char *format, va_list args) {
                 case 'X':
                 case 'o':
                 case 'u': {
-                    uint64_t n = va_arg(args, unsigned int);
+                    uint64_t n = va_arg(args, uint64_t);
                     nb = snprintf(item, MAX_ITEM, form, n);
                     break;
                 }
@@ -908,7 +921,7 @@ void janet_formatbv(JanetBuffer *b, const char *format, va_list args) {
                     janet_buffer_push_cstring(b, typestr(va_arg(args, Janet)));
                     break;
                 case 'T': {
-                    int types = va_arg(args, long);
+                    int types = va_arg(args, int);
                     pushtypes(b, types);
                     break;
                 }
@@ -1017,6 +1030,8 @@ void janet_buffer_format(
                                   janet_getinteger(argv, arg));
                     break;
                 }
+                case 'D':
+                case 'I':
                 case 'd':
                 case 'i': {
                     int64_t n = janet_getinteger64(argv, arg);

src/core/run.c

@@ -32,6 +32,7 @@ int janet_dobytes(JanetTable *env, const uint8_t *bytes, int32_t len, const char
     int errflags = 0, done = 0;
     int32_t index = 0;
     Janet ret = janet_wrap_nil();
+    JanetFiber *fiber = NULL;
     const uint8_t *where = sourcePath ? janet_cstring(sourcePath) : NULL;
 
     if (where) janet_gcroot(janet_wrap_string(where));
@@ -47,7 +48,7 @@ int janet_dobytes(JanetTable *env, const uint8_t *bytes, int32_t len, const char
             JanetCompileResult cres = janet_compile(form, env, where);
             if (cres.status == JANET_COMPILE_OK) {
                 JanetFunction *f = janet_thunk(cres.funcdef);
-                JanetFiber *fiber = janet_fiber(f, 64, 0, NULL);
+                fiber = janet_fiber(f, 64, 0, NULL);
                 fiber->env = env;
                 JanetSignal status = janet_continue(fiber, janet_wrap_nil(), &ret);
                 if (status != JANET_SIGNAL_OK && status != JANET_SIGNAL_EVENT) {
@@ -112,9 +113,14 @@ int janet_dobytes(JanetTable *env, const uint8_t *bytes, int32_t len, const char
 #ifdef JANET_EV
     /* Enter the event loop if we are not already in it */
     if (janet_vm.stackn == 0) {
-        janet_gcroot(ret);
+        if (fiber) {
+            janet_gcroot(janet_wrap_fiber(fiber));
+        }
         janet_loop();
-        janet_gcunroot(ret);
+        if (fiber) {
+            janet_gcunroot(janet_wrap_fiber(fiber));
+            ret = fiber->last_value;
+        }
     }
 #endif
     if (out) *out = ret;

src/include/janet.h

@@ -596,8 +596,7 @@ typedef enum {
     JANET_ASYNC_EVENT_READ = 6,
     JANET_ASYNC_EVENT_WRITE = 7,
     JANET_ASYNC_EVENT_COMPLETE = 8, /* Used on windows for IOCP */
-    JANET_ASYNC_EVENT_FAILED = 9, /* Used on windows for IOCP */
-    JANET_ASYNC_EVENT_USER = 10
+    JANET_ASYNC_EVENT_FAILED = 9 /* Used on windows for IOCP */
 } JanetAsyncEvent;
 
 typedef enum {
@@ -606,9 +605,7 @@ typedef enum {
     JANET_ASYNC_LISTEN_BOTH
 } JanetAsyncMode;
 
-/* Typedefs */
 typedef struct JanetStream JanetStream;
-typedef void (*JanetEVCallback)(JanetFiber *fiber, JanetAsyncEvent event);
 
 /* Wrapper around file descriptors and HANDLEs that can be polled. */
 struct JanetStream {
@@ -620,9 +617,24 @@ struct JanetStream {
     const void *methods; /* Methods for this stream */
 };
 
+typedef void (*JanetEVCallback)(JanetFiber *fiber, JanetAsyncEvent event);
+
+/* Start listening for events from a stream on the current root fiber. After
+ * calling this, users should call janet_await() before returning from the
+ * current C Function. This also will call janet_await.
+ * mode is which events to listen for, and callback is the function pointer to
+ * call when ever an event is sent from the event loop. state is an optional (can be NULL)
+ * pointer to data allocated with janet_malloc. This pointer will be passed to callback as
+ * fiber->ev_state. It will also be freed for you by the runtime when the event loop determines
+ * it can no longer be referenced. On windows, the contents of state MUST contained an OVERLAPPED struct. */
+JANET_API JANET_NO_RETURN void janet_async_start(JanetStream *stream, JanetAsyncMode mode, JanetEVCallback callback, void *state);
+
+/* Do not send any more events to the given callback. Call this after scheduling fiber to be resume
+ * or canceled. */
 JANET_API void janet_async_end(JanetFiber *fiber);
-JANET_API void *janet_async_start(JanetFiber *fiber, JanetStream *stream,
-                                  JanetAsyncMode mode, JanetEVCallback callback, size_t data_size);
+
+/* Needed for windows to mark a fiber as waiting for an IOCP completion event. Noop on other platforms. */
+JANET_API void janet_async_in_flight(JanetFiber *fiber);
 
 #endif
 
@@ -1488,22 +1500,22 @@ JANET_API void janet_ev_post_event(JanetVM *vm, JanetCallback cb, JanetEVGeneric
 JANET_API void janet_ev_default_threaded_callback(JanetEVGenericMessage return_value);
 
 /* Read async from a stream */
-JANET_API void janet_ev_read(JanetStream *stream, JanetBuffer *buf, int32_t nbytes);
-JANET_API void janet_ev_readchunk(JanetStream *stream, JanetBuffer *buf, int32_t nbytes);
+JANET_NO_RETURN JANET_API void janet_ev_read(JanetStream *stream, JanetBuffer *buf, int32_t nbytes);
+JANET_NO_RETURN JANET_API void janet_ev_readchunk(JanetStream *stream, JanetBuffer *buf, int32_t nbytes);
 #ifdef JANET_NET
-JANET_API void janet_ev_recv(JanetStream *stream, JanetBuffer *buf, int32_t nbytes, int flags);
-JANET_API void janet_ev_recvchunk(JanetStream *stream, JanetBuffer *buf, int32_t nbytes, int flags);
-JANET_API void janet_ev_recvfrom(JanetStream *stream, JanetBuffer *buf, int32_t nbytes, int flags);
+JANET_NO_RETURN JANET_API void janet_ev_recv(JanetStream *stream, JanetBuffer *buf, int32_t nbytes, int flags);
+JANET_NO_RETURN JANET_API void janet_ev_recvchunk(JanetStream *stream, JanetBuffer *buf, int32_t nbytes, int flags);
+JANET_NO_RETURN JANET_API void janet_ev_recvfrom(JanetStream *stream, JanetBuffer *buf, int32_t nbytes, int flags);
 #endif
 
 /* Write async to a stream */
-JANET_API void janet_ev_write_buffer(JanetStream *stream, JanetBuffer *buf);
-JANET_API void janet_ev_write_string(JanetStream *stream, JanetString str);
+JANET_NO_RETURN JANET_API void janet_ev_write_buffer(JanetStream *stream, JanetBuffer *buf);
+JANET_NO_RETURN JANET_API void janet_ev_write_string(JanetStream *stream, JanetString str);
 #ifdef JANET_NET
-JANET_API void janet_ev_send_buffer(JanetStream *stream, JanetBuffer *buf, int flags);
-JANET_API void janet_ev_send_string(JanetStream *stream, JanetString str, int flags);
-JANET_API void janet_ev_sendto_buffer(JanetStream *stream, JanetBuffer *buf, void *dest, int flags);
-JANET_API void janet_ev_sendto_string(JanetStream *stream, JanetString str, void *dest, int flags);
+JANET_NO_RETURN JANET_API void janet_ev_send_buffer(JanetStream *stream, JanetBuffer *buf, int flags);
+JANET_NO_RETURN JANET_API void janet_ev_send_string(JanetStream *stream, JanetString str, int flags);
+JANET_NO_RETURN JANET_API void janet_ev_sendto_buffer(JanetStream *stream, JanetBuffer *buf, void *dest, int flags);
+JANET_NO_RETURN JANET_API void janet_ev_sendto_string(JanetStream *stream, JanetString str, void *dest, int flags);
 #endif
 
 #endif