commit e6134a16e3bb133737b9895fcb95c8b5f8886d88
author Zach Johnson <zachoverflow@google.com> Fri Dec 11 10:40:26 2020 -0800
committer Zach Johnson <zachoverflow@google.com> Mon Dec 14 12:08:26 2020 -0800
tree 4959a7dfe60307a18afc4a0a5959f1398d299727
parent d9904535d755039fea2325f08d33e9c1b968bff1

rusty-gd: start writing scalar fields in write_to()

Bug: 171749953
Tag: #gd-refactor
Test: gd/cert/run --rhost
Change-Id: I07885881aa19538e62bd9cdcdac79127349f60b6

system/gd/packet/parser/fields/scalar_field.cc

diff --git a/system/gd/packet/parser/fields/scalar_field.cc b/system/gd/packet/parser/fields/scalar_field.cc
index a1189b7..dc93e2e 100644
--- a/system/gd/packet/parser/fields/scalar_field.cc
+++ b/system/gd/packet/parser/fields/scalar_field.cc
@@ -180,4 +180,35 @@
   }
 }
 
-void ScalarField::GenRustWriter(std::ostream&, Size, Size) const {}
+void ScalarField::GenRustWriter(std::ostream& s, Size start_offset, Size end_offset) const {
+  Size size = GetSize();
+  int num_leading_bits = GetRustBitOffset(s, start_offset, end_offset, GetSize());
+
+  s << "let " << GetName() << " = self." << GetName() << ";";
+  if (util::RoundSizeUp(size.bits()) != size.bits()) {
+    uint64_t mask = 0;
+    for (int i = 0; i < size.bits(); i++) {
+      mask <<= 1;
+      mask |= 1;
+    }
+    s << "let " << GetName() << " = ";
+    s << GetName() << " & 0x" << std::hex << mask << std::dec << ";";
+  }
+
+  int access_offset = 0;
+  if (num_leading_bits != 0) {
+    access_offset = -1;
+    uint64_t mask = 0;
+    for (int i = 0; i < num_leading_bits; i++) {
+      mask <<= 1;
+      mask |= 1;
+    }
+    s << "let " << GetName() << " = (" << GetName() << " << " << num_leading_bits << ") | ("
+      << "(buffer[" << start_offset.bytes() << "] as " << GetRustDataType() << ") & 0x" << std::hex << mask << std::dec
+      << ");";
+  }
+
+  s << "buffer[" << start_offset.bytes() + access_offset << ".."
+    << start_offset.bytes() + GetSize().bytes() + access_offset << "].copy_from_slice(&" << GetName()
+    << ".to_le_bytes());";
+}

system/gd/packet/parser/packet_def.cc

diff --git a/system/gd/packet/parser/packet_def.cc b/system/gd/packet/parser/packet_def.cc
index 7e31fe5..9b2b8a1 100644
--- a/system/gd/packet/parser/packet_def.cc
+++ b/system/gd/packet/parser/packet_def.cc
@@ -881,6 +881,10 @@
 
   fields = fields_.GetFieldsWithoutTypes({
       BodyField::kFieldType,
+      CountField::kFieldType,
+      PaddingField::kFieldType,
+      ReservedField::kFieldType,
+      SizeField::kFieldType,
   });
 
   for (auto const& field : fields) {