1 files changed, 470 insertions, 0 deletions
diff --git a/src/3rdparty/harfbuzz-ng/src/hb-wasm-shape.cc b/src/3rdparty/harfbuzz-ng/src/hb-wasm-shape.cc
new file mode 100644
index 0000000000..a8b91879a4
--- /dev/null
+++ b/src/3rdparty/harfbuzz-ng/src/hb-wasm-shape.cc
@@ -0,0 +1,470 @@
+/*
+ * Copyright © 2011  Google, Inc.
+ *
+ *  This is part of HarfBuzz, a text shaping library.
+ *
+ * Permission is hereby granted, without written agreement and without
+ * license or royalty fees, to use, copy, modify, and distribute this
+ * software and its documentation for any purpose, provided that the
+ * above copyright notice and the following two paragraphs appear in
+ * all copies of this software.
+ *
+ * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
+ * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
+ * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
+ * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
+ * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
+ * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
+ * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
+ *
+ * Google Author(s): Behdad Esfahbod
+ */
+
+#undef HB_DEBUG_WASM
+#define HB_DEBUG_WASM 1
+
+#include "hb-shaper-impl.hh"
+
+#ifdef HAVE_WASM
+
+/* Compile wasm-micro-runtime with:
+ *
+ * $ cmake -DWAMR_BUILD_MULTI_MODULE=1 -DWAMR_BUILD_REF_TYPES=1 -DWAMR_BUILD_FAST_JIT=1
+ * $ make
+ *
+ * If you manage to build a wasm shared module successfully and want to use it,
+ * do the following:
+ *
+ *   - Add -DWAMR_BUILD_MULTI_MODULE=1 to your cmake build for wasm-micro-runtime,
+ *
+ *   - Remove the #define HB_WASM_NO_MODULES line below,
+ *
+ *   - Install your shared module with name ending in .wasm in
+ *     $(prefix)/$(libdir)/harfbuzz/wasm/
+ *
+ *   - Build your font's wasm code importing the shared modules with the desired
+ *     name. This can be done eg.: __attribute__((import_module("graphite2")))
+ *     before each symbol in the shared-module's headers.
+ *
+ *   - Try shaping your font and hope for the best...
+ *
+ * I haven't been able to get this to work since emcc's support for shared libraries
+ * requires support from the host that seems to be missing from wasm-micro-runtime?
+ */
+
+#include "hb-wasm-api.hh"
+#include "hb-wasm-api-list.hh"
+
+#ifndef HB_WASM_NO_MODULES
+#define HB_WASM_NO_MODULES
+#endif
+
+
+#ifndef HB_WASM_NO_MODULES
+static bool HB_UNUSED
+_hb_wasm_module_reader (const char *module_name,
+		       uint8_t **p_buffer, uint32_t *p_size)
+{
+  char path[sizeof (HB_WASM_MODULE_DIR) + 64] = HB_WASM_MODULE_DIR "/";
+  strncat (path, module_name, sizeof (path) - sizeof (HB_WASM_MODULE_DIR) - 16);
+  strncat (path, ".wasm", 6);
+
+  auto *blob = hb_blob_create_from_file (path);
+
+  unsigned length;
+  auto *data = hb_blob_get_data (blob, &length);
+
+  *p_buffer = (uint8_t *) hb_malloc (length);
+
+  if (length && !p_buffer)
+    return false;
+
+  memcpy (*p_buffer, data, length);
+  *p_size = length;
+
+  hb_blob_destroy (blob);
+
+  return true;
+}
+
+static void HB_UNUSED
+_hb_wasm_module_destroyer (uint8_t *buffer, uint32_t size)
+{
+  hb_free (buffer);
+}
+#endif
+
+/*
+ * shaper face data
+ */
+
+#define HB_WASM_TAG_WASM HB_TAG('W','a','s','m')
+
+struct hb_wasm_shape_plan_t {
+  wasm_module_inst_t module_inst;
+  wasm_exec_env_t exec_env;
+  ptr_d(void, wasm_shape_plan);
+};
+
+struct hb_wasm_face_data_t {
+  hb_blob_t *wasm_blob;
+  wasm_module_t wasm_module;
+  mutable hb_atomic_ptr_t<hb_wasm_shape_plan_t> plan;
+};
+
+static bool
+_hb_wasm_init ()
+{
+  /* XXX
+   *
+   * Umm. Make this threadsafe. How?!
+   * It's clunky that we can't allocate a static mutex.
+   * So we have to first allocate one on the heap atomically...
+   *
+   * Do we also need to lock around module creation?
+   *
+   * Also, wasm-micro-runtime uses a singleton instance. So if
+   * another library or client uses it, all bets are off. :-(
+   * If nothing else, around HB_REF2OBJ().
+   */
+
+  static bool initialized;
+  if (initialized)
+    return true;
+
+  RuntimeInitArgs init_args;
+  hb_memset (&init_args, 0, sizeof (RuntimeInitArgs));
+
+  init_args.mem_alloc_type = Alloc_With_Allocator;
+  init_args.mem_alloc_option.allocator.malloc_func = (void *) hb_malloc;
+  init_args.mem_alloc_option.allocator.realloc_func = (void *) hb_realloc;
+  init_args.mem_alloc_option.allocator.free_func = (void *) hb_free;
+
+  // Native symbols need below registration phase
+  init_args.n_native_symbols = ARRAY_LENGTH (_hb_wasm_native_symbols);
+  init_args.native_module_name = "env";
+  init_args.native_symbols = _hb_wasm_native_symbols;
+
+  if (unlikely (!wasm_runtime_full_init (&init_args)))
+  {
+    DEBUG_MSG (WASM, nullptr, "Init runtime environment failed.");
+    return false;
+  }
+
+#ifndef HB_WASM_NO_MODULES
+  wasm_runtime_set_module_reader (_hb_wasm_module_reader,
+				  _hb_wasm_module_destroyer);
+#endif
+
+  initialized = true;
+  return true;
+}
+
+hb_wasm_face_data_t *
+_hb_wasm_shaper_face_data_create (hb_face_t *face)
+{
+  char error[128];
+  hb_wasm_face_data_t *data = nullptr;
+  hb_blob_t *wasm_blob = nullptr;
+  wasm_module_t wasm_module = nullptr;
+
+  wasm_blob = hb_face_reference_table (face, HB_WASM_TAG_WASM);
+  unsigned length = hb_blob_get_length (wasm_blob);
+  if (!length)
+    goto fail;
+
+  if (!_hb_wasm_init ())
+    goto fail;
+
+  wasm_module = wasm_runtime_load ((uint8_t *) hb_blob_get_data_writable (wasm_blob, nullptr),
+				   length, error, sizeof (error));
+  if (unlikely (!wasm_module))
+  {
+    DEBUG_MSG (WASM, nullptr, "Load wasm module failed: %s", error);
+    goto fail;
+  }
+
+  data = (hb_wasm_face_data_t *) hb_calloc (1, sizeof (hb_wasm_face_data_t));
+  if (unlikely (!data))
+    goto fail;
+
+  data->wasm_blob = wasm_blob;
+  data->wasm_module = wasm_module;
+
+  return data;
+
+fail:
+  if (wasm_module)
+      wasm_runtime_unload (wasm_module);
+  hb_blob_destroy (wasm_blob);
+  hb_free (data);
+  return nullptr;
+}
+
+static hb_wasm_shape_plan_t *
+acquire_shape_plan (hb_face_t *face,
+		    const hb_wasm_face_data_t *face_data)
+{
+  char error[128];
+
+  /* Fetch cached one if available. */
+  hb_wasm_shape_plan_t *plan = face_data->plan.get_acquire ();
+  if (likely (plan && face_data->plan.cmpexch (plan, nullptr)))
+    return plan;
+
+  plan = (hb_wasm_shape_plan_t *) hb_calloc (1, sizeof (hb_wasm_shape_plan_t));
+
+  wasm_module_inst_t module_inst = nullptr;
+  wasm_exec_env_t exec_env = nullptr;
+  wasm_function_inst_t func = nullptr;
+
+  constexpr uint32_t stack_size = 32 * 1024, heap_size = 2 * 1024 * 1024;
+
+  module_inst = plan->module_inst = wasm_runtime_instantiate (face_data->wasm_module,
+							      stack_size, heap_size,
+							      error, sizeof (error));
+  if (unlikely (!module_inst))
+  {
+    DEBUG_MSG (WASM, face_data, "Create wasm module instance failed: %s", error);
+    goto fail;
+  }
+
+  exec_env = plan->exec_env = wasm_runtime_create_exec_env (module_inst,
+							    stack_size);
+  if (unlikely (!exec_env)) {
+    DEBUG_MSG (WASM, face_data, "Create wasm execution environment failed.");
+    goto fail;
+  }
+
+  func = wasm_runtime_lookup_function (module_inst, "shape_plan_create");
+  if (func)
+  {
+    wasm_val_t results[1];
+    wasm_val_t arguments[1];
+
+    HB_OBJ2REF (face);
+    if (unlikely (!faceref))
+    {
+      DEBUG_MSG (WASM, face_data, "Failed to register face object.");
+      goto fail;
+    }
+
+    results[0].kind = WASM_I32;
+    arguments[0].kind = WASM_I32;
+    arguments[0].of.i32 = faceref;
+    bool ret = wasm_runtime_call_wasm_a (exec_env, func,
+					 ARRAY_LENGTH (results), results,
+					 ARRAY_LENGTH (arguments), arguments);
+
+    if (unlikely (!ret))
+    {
+      DEBUG_MSG (WASM, module_inst, "Calling shape_plan_create() failed: %s",
+		 wasm_runtime_get_exception (module_inst));
+      goto fail;
+    }
+    plan->wasm_shape_planptr = results[0].of.i32;
+  }
+
+  return plan;
+
+fail:
+
+  if (exec_env)
+    wasm_runtime_destroy_exec_env (exec_env);
+  if (module_inst)
+    wasm_runtime_deinstantiate (module_inst);
+  hb_free (plan);
+  return nullptr;
+}
+
+static void
+release_shape_plan (const hb_wasm_face_data_t *face_data,
+		    hb_wasm_shape_plan_t *plan,
+		    bool cache = false)
+{
+  if (cache && face_data->plan.cmpexch (nullptr, plan))
+    return;
+
+  auto *module_inst = plan->module_inst;
+  auto *exec_env = plan->exec_env;
+
+  /* Is there even any point to having a shape_plan_destroy function
+   * and calling it? */
+  if (plan->wasm_shape_planptr)
+  {
+
+    auto *func = wasm_runtime_lookup_function (module_inst, "shape_plan_destroy");
+    if (func)
+    {
+      wasm_val_t arguments[1];
+
+      arguments[0].kind = WASM_I32;
+      arguments[0].of.i32 = plan->wasm_shape_planptr;
+      bool ret = wasm_runtime_call_wasm_a (exec_env, func,
+					   0, nullptr,
+					   ARRAY_LENGTH (arguments), arguments);
+
+      if (unlikely (!ret))
+      {
+	DEBUG_MSG (WASM, module_inst, "Calling shape_plan_destroy() failed: %s",
+		   wasm_runtime_get_exception (module_inst));
+      }
+    }
+  }
+
+  wasm_runtime_destroy_exec_env (exec_env);
+  wasm_runtime_deinstantiate (module_inst);
+  hb_free (plan);
+}
+
+void
+_hb_wasm_shaper_face_data_destroy (hb_wasm_face_data_t *data)
+{
+  if (data->plan.get_relaxed ())
+    release_shape_plan (data, data->plan);
+  wasm_runtime_unload (data->wasm_module);
+  hb_blob_destroy (data->wasm_blob);
+  hb_free (data);
+}
+
+
+/*
+ * shaper font data
+ */
+
+struct hb_wasm_font_data_t {};
+
+hb_wasm_font_data_t *
+_hb_wasm_shaper_font_data_create (hb_font_t *font HB_UNUSED)
+{
+  return (hb_wasm_font_data_t *) HB_SHAPER_DATA_SUCCEEDED;
+}
+
+void
+_hb_wasm_shaper_font_data_destroy (hb_wasm_font_data_t *data HB_UNUSED)
+{
+}
+
+
+/*
+ * shaper
+ */
+
+hb_bool_t
+_hb_wasm_shape (hb_shape_plan_t    *shape_plan,
+		hb_font_t          *font,
+		hb_buffer_t        *buffer,
+		const hb_feature_t *features,
+		unsigned int        num_features)
+{
+  if (unlikely (buffer->in_error ()))
+    return false;
+
+  bool ret = true;
+  hb_face_t *face = font->face;
+  const hb_wasm_face_data_t *face_data = face->data.wasm;
+
+  bool retried = false;
+  if (0)
+  {
+retry:
+    DEBUG_MSG (WASM, font, "Retrying...");
+  }
+
+  wasm_function_inst_t func = nullptr;
+
+  hb_wasm_shape_plan_t *plan = acquire_shape_plan (face, face_data);
+  if (unlikely (!plan))
+  {
+    DEBUG_MSG (WASM, face_data, "Acquiring shape-plan failed.");
+    return false;
+  }
+
+  auto *module_inst = plan->module_inst;
+  auto *exec_env = plan->exec_env;
+
+  HB_OBJ2REF (font);
+  HB_OBJ2REF (buffer);
+  if (unlikely (!fontref || !bufferref))
+  {
+    DEBUG_MSG (WASM, module_inst, "Failed to register objects.");
+    goto fail;
+  }
+
+  func = wasm_runtime_lookup_function (module_inst, "shape");
+  if (unlikely (!func))
+  {
+    DEBUG_MSG (WASM, module_inst, "Shape function not found.");
+    goto fail;
+  }
+
+  wasm_val_t results[1];
+  wasm_val_t arguments[5];
+
+  results[0].kind = WASM_I32;
+  arguments[0].kind = WASM_I32;
+  arguments[0].of.i32 = plan->wasm_shape_planptr;
+  arguments[1].kind = WASM_I32;
+  arguments[1].of.i32 = fontref;
+  arguments[2].kind = WASM_I32;
+  arguments[2].of.i32 = bufferref;
+  arguments[3].kind = WASM_I32;
+  arguments[3].of.i32 = num_features ? wasm_runtime_module_dup_data (module_inst,
+								     (const char *) features,
+								     num_features * sizeof (features[0])) : 0;
+  arguments[4].kind = WASM_I32;
+  arguments[4].of.i32 = num_features;
+
+  ret = wasm_runtime_call_wasm_a (exec_env, func,
+				  ARRAY_LENGTH (results), results,
+				  ARRAY_LENGTH (arguments), arguments);
+
+  if (num_features)
+    wasm_runtime_module_free (module_inst, arguments[2].of.i32);
+
+  if (unlikely (!ret || !results[0].of.i32))
+  {
+    DEBUG_MSG (WASM, module_inst, "Calling shape() failed: %s",
+	       wasm_runtime_get_exception (module_inst));
+    if (!buffer->ensure_unicode ())
+    {
+      DEBUG_MSG (WASM, font, "Shape failed but buffer is not in Unicode; failing...");
+      goto fail;
+    }
+    if (retried)
+    {
+      DEBUG_MSG (WASM, font, "Giving up...");
+      goto fail;
+    }
+    buffer->successful = true;
+    retried = true;
+    release_shape_plan (face_data, plan);
+    plan = nullptr;
+    goto retry;
+  }
+
+  /* TODO Regularize clusters according to direction & cluster level,
+   * such that client doesn't crash with unmet expectations. */
+
+  if (!results[0].of.i32)
+  {
+fail:
+    ret = false;
+  }
+
+  release_shape_plan (face_data, plan, ret);
+
+  if (ret)
+  {
+    buffer->clear_glyph_flags ();
+    buffer->unsafe_to_break ();
+  }
+
+  return ret;
+}
+
+#endif