[subset] add an experimental API that can override name strings for specified name_id

src/gen-def.py

@@ -23,6 +23,7 @@ if '--experimental-api' not in sys.argv:
 hb_subset_input_pin_axis_location
 hb_subset_input_pin_axis_to_default
 hb_subset_preprocess
+hb_subset_input_override_name_table
 """.splitlines ()
 	symbols = [x for x in symbols if x not in experimental_symbols]
 symbols = "\n".join (symbols)

src/hb-ot-name-table.hh

@@ -30,10 +30,55 @@
 #include "hb-open-type.hh"
 #include "hb-ot-name-language.hh"
 #include "hb-aat-layout.hh"
+#include "hb-utf.hh"
 
 
 namespace OT {
 
+template <typename in_utf_t, typename out_utf_t>
+inline unsigned int
+hb_ot_name_convert_utf (hb_bytes_t                       bytes,
+			unsigned int                    *text_size /* IN/OUT */,
+			typename out_utf_t::codepoint_t *text /* OUT */)
+{
+  unsigned int src_len = bytes.length / sizeof (typename in_utf_t::codepoint_t);
+  const typename in_utf_t::codepoint_t *src = (const typename in_utf_t::codepoint_t *) bytes.arrayZ;
+  const typename in_utf_t::codepoint_t *src_end = src + src_len;
+
+  typename out_utf_t::codepoint_t *dst = text;
+
+  hb_codepoint_t unicode;
+  const hb_codepoint_t replacement = HB_BUFFER_REPLACEMENT_CODEPOINT_DEFAULT;
+
+  if (text_size && *text_size)
+  {
+    (*text_size)--; /* Same room for NUL-termination. */
+    const typename out_utf_t::codepoint_t *dst_end = text + *text_size;
+
+    while (src < src_end && dst < dst_end)
+    {
+      const typename in_utf_t::codepoint_t *src_next = in_utf_t::next (src, src_end, &unicode, replacement);
+      typename out_utf_t::codepoint_t *dst_next = out_utf_t::encode (dst, dst_end, unicode);
+      if (dst_next == dst)
+	break; /* Out-of-room. */
+
+      dst = dst_next;
+      src = src_next;
+    }
+
+    *text_size = dst - text;
+    *dst = 0; /* NUL-terminate. */
+  }
+
+  /* Accumulate length of rest. */
+  unsigned int dst_len = dst - text;
+  while (src < src_end)
+  {
+    src = in_utf_t::next (src, src_end, &unicode, replacement);
+    dst_len += out_utf_t::encode_len (unicode);
+  }
+  return dst_len;
+}
 
 #define entry_score var.u16[0]
 #define entry_index var.u16[1]
@@ -97,12 +142,39 @@ struct NameRecord
     return UNSUPPORTED;
   }
 
-  NameRecord* copy (hb_serialize_context_t *c, const void *base) const
+  NameRecord* copy (hb_serialize_context_t *c, const void *base,
+                    const hb_hashmap_t<unsigned, hb_bytes_t> *name_table_overrides) const
   {
     TRACE_SERIALIZE (this);
+    auto snap = c->snapshot ();
     auto *out = c->embed (this);
     if (unlikely (!out)) return_trace (nullptr);
-    out->offset.serialize_copy (c, offset, base, 0, hb_serialize_context_t::Tail, length);
+    if (name_table_overrides->has (nameID)) {
+      hb_bytes_t name_bytes = name_table_overrides->get (nameID);
+      char *name_str_utf16_be = (char *) hb_calloc ((name_bytes.length + 1) * 4, 1);
+      unsigned text_size = hb_ot_name_convert_utf<hb_utf8_t, hb_utf16_be_t> (name_bytes, nullptr,
+                                                                             (hb_utf16_be_t::codepoint_t *) name_str_utf16_be);
+
+      text_size++; // needs to consider NULL terminator for use in hb_ot_name_convert_utf()
+      hb_ot_name_convert_utf<hb_utf8_t, hb_utf16_be_t> (name_bytes, &text_size,
+                                                        (hb_utf16_be_t::codepoint_t *) name_str_utf16_be);
+
+      unsigned encoded_byte_len = text_size * hb_utf16_be_t::codepoint_t::static_size;
+      if (!encoded_byte_len || !c->check_assign (out->length, encoded_byte_len, HB_SERIALIZE_ERROR_INT_OVERFLOW)) {
+        c->revert (snap);
+        hb_free (name_str_utf16_be);
+        return_trace (nullptr);
+      }
+
+      hb_bytes_t utf16_be_bytes (name_str_utf16_be, encoded_byte_len);
+      out->offset = 0;
+      c->push ();
+      utf16_be_bytes.copy (c);
+      c->add_link (out->offset, c->pop_pack (), hb_serialize_context_t::Tail, 0);
+      hb_free (name_str_utf16_be);
+    } else {
+      out->offset.serialize_copy (c, offset, base, 0, hb_serialize_context_t::Tail, length);
+    }
     return_trace (out);
   }
 
@@ -216,7 +288,8 @@ struct name
 	    hb_requires (hb_is_source_of (Iterator, const NameRecord &))>
   bool serialize (hb_serialize_context_t *c,
 		  Iterator it,
-		  const void *src_string_pool)
+		  const void *src_string_pool,
+		  const hb_hashmap_t<unsigned, hb_bytes_t> *name_table_overrides)
   {
     TRACE_SERIALIZE (this);
 
@@ -238,7 +311,7 @@ struct name
 
     records.qsort ();
 
-    c->copy_all (records, src_string_pool);
+    c->copy_all (records, src_string_pool, name_table_overrides);
     hb_free (records.arrayZ);
 
 
@@ -267,7 +340,7 @@ struct name
     })
     ;
 
-    name_prime->serialize (c->serializer, it, std::addressof (this + stringOffset));
+    name_prime->serialize (c->serializer, it, std::addressof (this + stringOffset), c->plan->name_table_overrides);
     return_trace (name_prime->count);
   }
 

src/hb-ot-name.cc

@@ -64,52 +64,6 @@ hb_ot_name_list_names (hb_face_t    *face,
   return (const hb_ot_name_entry_t *) name.names;
 }
 
-
-template <typename in_utf_t, typename out_utf_t>
-static inline unsigned int
-hb_ot_name_convert_utf (hb_bytes_t                       bytes,
-			unsigned int                    *text_size /* IN/OUT */,
-			typename out_utf_t::codepoint_t *text /* OUT */)
-{
-  unsigned int src_len = bytes.length / sizeof (typename in_utf_t::codepoint_t);
-  const typename in_utf_t::codepoint_t *src = (const typename in_utf_t::codepoint_t *) bytes.arrayZ;
-  const typename in_utf_t::codepoint_t *src_end = src + src_len;
-
-  typename out_utf_t::codepoint_t *dst = text;
-
-  hb_codepoint_t unicode;
-  const hb_codepoint_t replacement = HB_BUFFER_REPLACEMENT_CODEPOINT_DEFAULT;
-
-  if (text_size && *text_size)
-  {
-    (*text_size)--; /* Save room for NUL-termination. */
-    const typename out_utf_t::codepoint_t *dst_end = text + *text_size;
-
-    while (src < src_end && dst < dst_end)
-    {
-      const typename in_utf_t::codepoint_t *src_next = in_utf_t::next (src, src_end, &unicode, replacement);
-      typename out_utf_t::codepoint_t *dst_next = out_utf_t::encode (dst, dst_end, unicode);
-      if (dst_next == dst)
-	break; /* Out-of-room. */
-
-      dst = dst_next;
-      src = src_next;
-    }
-
-    *text_size = dst - text;
-    *dst = 0; /* NUL-terminate. */
-  }
-
-  /* Accumulate length of rest. */
-  unsigned int dst_len = dst - text;
-  while (src < src_end)
-  {
-    src = in_utf_t::next (src, src_end, &unicode, replacement);
-    dst_len += out_utf_t::encode_len (unicode);
-  }
-  return dst_len;
-}
-
 template <typename utf_t>
 static inline unsigned int
 hb_ot_name_get_utf (hb_face_t       *face,
@@ -130,10 +84,10 @@ hb_ot_name_get_utf (hb_face_t       *face,
     hb_bytes_t bytes = name.get_name (idx);
 
     if (width == 2) /* UTF16-BE */
-      return hb_ot_name_convert_utf<hb_utf16_be_t, utf_t> (bytes, text_size, text);
+      return OT::hb_ot_name_convert_utf<hb_utf16_be_t, utf_t> (bytes, text_size, text);
 
     if (width == 1) /* ASCII */
-      return hb_ot_name_convert_utf<hb_ascii_t, utf_t> (bytes, text_size, text);
+      return OT::hb_ot_name_convert_utf<hb_ascii_t, utf_t> (bytes, text_size, text);
   }
 
   if (text_size)
@@ -227,5 +181,4 @@ hb_ot_name_get_utf32 (hb_face_t       *face,
   return hb_ot_name_get_utf<hb_utf32_t> (face, name_id, language, text_size, text);
 }
 
-
 #endif

src/hb-subset-input.cc

@@ -49,8 +49,9 @@ hb_subset_input_create_or_fail (void)
     set = hb_set_create ();
 
   input->axes_location = hb_hashmap_create<hb_tag_t, float> ();
+  input->name_table_overrides = hb_hashmap_create<unsigned, hb_bytes_t> ();
 
-  if (!input->axes_location || input->in_error ())
+  if (!input->axes_location || !input->name_table_overrides || input->in_error ())
   {
     hb_subset_input_destroy (input);
     return nullptr;
@@ -248,6 +249,14 @@ hb_subset_input_destroy (hb_subset_input_t *input)
 
   hb_hashmap_destroy (input->axes_location);
 
+  if (input->name_table_overrides)
+  {
+    for (auto _ : input->name_table_overrides->values ())
+      _.fini ();
+  }
+
+  hb_hashmap_destroy (input->name_table_overrides);
+
   hb_free (input);
 }
 
@@ -478,4 +487,43 @@ hb_subset_preprocess (hb_face_t *source)
 
   return new_source;
 }
+
+/**
+ * hb_subset_input_override_name_table:
+ * @input: a #hb_subset_input_t object.
+ * @name_id: name_id of a nameRecord
+ * @name_str: pointer to name string new value or null to indicate should remove
+ * @str_len: the size of @name_str, or -1 if it is `NULL`-terminated
+ *
+ * Override the name string of a nameRecord with specified name_id
+ * Since: EXPERIMENTAL
+ **/
+HB_EXTERN void
+hb_subset_input_override_name_table (hb_subset_input_t  *input,
+                                     hb_ot_name_id_t     name_id,
+                                     const char         *name_str,
+                                     int                 str_len /* -1 means nul-terminated */)
+{
+  if (!name_str)
+  {
+    hb_set_del (hb_subset_input_set(input, HB_SUBSET_SETS_NAME_ID), name_id);
+    return;
+  }
+
+  if (str_len == -1)
+    str_len = strlen (name_str);
+
+  if (!str_len)
+  {
+    hb_set_del (hb_subset_input_set(input, HB_SUBSET_SETS_NAME_ID), name_id);
+    return;
+  }
+
+  char *override_name = (char *) hb_malloc (str_len);
+  if (unlikely (!override_name)) return;
+
+  strncpy (override_name, name_str, str_len);
+  input->name_table_overrides->set (name_id, hb_bytes_t (override_name, str_len));
+}
+
 #endif

src/hb-subset-input.hh

@@ -61,6 +61,7 @@ struct hb_subset_input_t
   unsigned flags;
   bool attach_accelerator_data = false;
   hb_hashmap_t<hb_tag_t, float> *axes_location;
+  hb_hashmap_t<unsigned, hb_bytes_t> *name_table_overrides;
 
   inline unsigned num_sets () const
   {
@@ -80,7 +81,7 @@ struct hb_subset_input_t
         return true;
     }
 
-    return axes_location->in_error ();
+    return axes_location->in_error () || name_table_overrides->in_error ();
   }
 };
 

src/hb-subset-plan.cc

@@ -848,6 +848,29 @@ hb_subset_plan_create_or_fail (hb_face_t	 *face,
   plan->check_success (plan->vmtx_map = hb_hashmap_create<unsigned, hb_pair_t<unsigned, int>> ());
   plan->check_success (plan->hmtx_map = hb_hashmap_create<unsigned, hb_pair_t<unsigned, int>> ());
 
+  plan->check_success (plan->name_table_overrides = hb_hashmap_create<unsigned, hb_bytes_t> ());
+  if (plan->name_table_overrides && input->name_table_overrides)
+  {
+    for (auto _ : *input->name_table_overrides)
+    {
+      unsigned name_id = _.first;
+      hb_bytes_t name_bytes = _.second;
+      unsigned len = name_bytes.length;
+
+      char *name_str = (char *) hb_malloc (len);
+      if (unlikely (!plan->check_success (name_str)))
+      {
+        for (auto bytes : plan->name_table_overrides->values ())
+          bytes.fini ();
+        break;
+      }
+
+      strncpy (name_str, name_bytes.arrayZ, len);
+      plan->name_table_overrides->set (name_id, hb_bytes_t (name_str, len));
+    }
+  }
+
+
   void* accel = hb_face_get_user_data(face, hb_subset_accelerator_t::user_data_key());
 
   plan->attach_accelerator_data = input->attach_accelerator_data;

src/hb-subset-plan.hh

@@ -87,6 +87,13 @@ struct hb_subset_plan_t
     hb_hashmap_destroy (vmtx_map);
     hb_hashmap_destroy (layout_variation_idx_delta_map);
 
+    if (name_table_overrides)
+    {
+      for (auto _ : name_table_overrides->values ())
+        _.fini ();
+    }
+    hb_hashmap_destroy (name_table_overrides);
+
     if (user_axes_location)
     {
       hb_object_destroy (user_axes_location);
@@ -191,6 +198,10 @@ struct hb_subset_plan_t
   //vmtx metrics map: new gid->(advance, lsb)
   hb_hashmap_t<unsigned, hb_pair_t<unsigned, int>> *vmtx_map;
 
+  // name table overrides map: name_id->name string new value or None
+  // to indicate should remove
+  hb_hashmap_t<unsigned, hb_bytes_t> *name_table_overrides;
+
   const hb_subset_accelerator_t* accelerator;
 
  public:

src/hb-subset.h

@@ -28,6 +28,7 @@
 #define HB_SUBSET_H
 
 #include "hb.h"
+#include "hb-ot.h"
 
 HB_BEGIN_DECLS
 
@@ -184,6 +185,12 @@ hb_subset_input_pin_axis_location (hb_subset_input_t  *input,
 HB_EXTERN hb_face_t *
 hb_subset_preprocess (hb_face_t *source);
 
+HB_EXTERN void
+hb_subset_input_override_name_table (hb_subset_input_t  *input,
+				     hb_ot_name_id_t     name_id,
+				     const char         *name_str,
+				     int                 str_len);
+
 #endif
 
 HB_EXTERN hb_face_t *

test/api/test-subset-nameids.c

@@ -67,6 +67,38 @@ test_subset_nameids_with_dup_strs (void)
   hb_face_destroy (face_expected);
 }
 
+#ifdef HB_EXPERIMENTAL_API
+static void
+test_subset_name_overrides (void)
+{
+  hb_face_t *face_origin = hb_test_open_font_file ("fonts/nameID.origin.ttf");
+  hb_face_t *face_expected = hb_test_open_font_file ("fonts/nameID.override.expected.ttf");
+
+  char str1[] = "Roboto Test";
+  char str2[] = "Bold";
+  char str6[] = "Roboto-Bold";
+ 
+  hb_set_t *name_ids = hb_set_create();
+  hb_face_t *face_subset;
+  hb_set_add_range (name_ids, 0, 15);
+
+  hb_subset_input_t *subset_input = hb_subset_test_create_input_from_nameids (name_ids);
+  hb_subset_input_override_name_table (subset_input, 1, str1, -1);
+  hb_subset_input_override_name_table (subset_input, 2, str2, 4);
+  hb_subset_input_override_name_table (subset_input, 6, str6, -1);
+  hb_subset_input_override_name_table (subset_input, 14, NULL, -1);
+
+  face_subset = hb_subset_test_create_subset (face_origin, subset_input);
+  hb_set_destroy (name_ids);
+
+  hb_subset_test_check (face_expected, face_subset, HB_TAG ('n','a','m','e'));
+
+  hb_face_destroy (face_subset);
+  hb_face_destroy (face_origin);
+  hb_face_destroy (face_expected);
+}
+#endif
+
 int
 main (int argc, char **argv)
 {
@@ -74,6 +106,9 @@ main (int argc, char **argv)
 
   hb_test_add (test_subset_nameids);
   hb_test_add (test_subset_nameids_with_dup_strs);
+#ifdef HB_EXPERIMENTAL_API
+  hb_test_add (test_subset_name_overrides);
+#endif
 
   return hb_test_run();
 }