androidfw: Add tests for compact entries/short offsets

Bug: 237583012

This CL tests iteration through the resource entries with combinations of:

  - 32-bit offsets + normal entry/value pairs
  - 32-bit offsets + compact entries
  - 16-bit offsets + normal entry/value pairs
  - 16-bit offsets + compact entries

Change-Id: Ia348c4b05dde0bdc31e75671126b98809643f0f1
diff --git a/libs/androidfw/tests/TypeWrappers_test.cpp b/libs/androidfw/tests/TypeWrappers_test.cpp
index aba3ab3..ed30904 100644
--- a/libs/androidfw/tests/TypeWrappers_test.cpp
+++ b/libs/androidfw/tests/TypeWrappers_test.cpp
@@ -14,6 +14,7 @@
  * limitations under the License.
  */
 
+#include <algorithm>
 #include <androidfw/ResourceTypes.h>
 #include <androidfw/TypeWrappers.h>
 #include <utils/String8.h>
@@ -22,88 +23,123 @@
 
 namespace android {
 
-void* createTypeData() {
-    ResTable_type t;
-    memset(&t, 0, sizeof(t));
+// create a ResTable_type in memory with a vector of Res_value*
+static ResTable_type* createTypeTable(std::vector<Res_value*>& values,
+                             bool compact_entry = false,
+                             bool short_offsets = false)
+{
+    ResTable_type t{};
     t.header.type = RES_TABLE_TYPE_TYPE;
     t.header.headerSize = sizeof(t);
+    t.header.size = sizeof(t);
     t.id = 1;
-    t.entryCount = 3;
+    t.flags = short_offsets ? ResTable_type::FLAG_OFFSET16 : 0;
 
-    uint32_t offsets[3];
-    t.entriesStart = t.header.headerSize + sizeof(offsets);
-    t.header.size = t.entriesStart;
+    t.header.size += values.size() * (short_offsets ? sizeof(uint16_t) : sizeof(uint32_t));
+    t.entriesStart = t.header.size;
+    t.entryCount = values.size();
 
-    offsets[0] = 0;
-    ResTable_entry e1;
-    memset(&e1, 0, sizeof(e1));
-    e1.full.size = sizeof(e1);
-    e1.full.key.index = 0;
-    t.header.size += sizeof(e1);
+    size_t entry_size = compact_entry ? sizeof(ResTable_entry)
+                                      : sizeof(ResTable_entry) + sizeof(Res_value);
+    for (auto const v : values) {
+        t.header.size += v ? entry_size : 0;
+    }
 
-    Res_value v1;
-    memset(&v1, 0, sizeof(v1));
-    t.header.size += sizeof(v1);
+    uint8_t* data = (uint8_t *)malloc(t.header.size);
+    uint8_t* p_header = data;
+    uint8_t* p_offsets = data + t.header.headerSize;
+    uint8_t* p_entries = data + t.entriesStart;
 
-    offsets[1] = ResTable_type::NO_ENTRY;
+    memcpy(p_header, &t, sizeof(t));
 
-    offsets[2] = sizeof(e1) + sizeof(v1);
-    ResTable_entry e2;
-    memset(&e2, 0, sizeof(e2));
-    e2.full.size = sizeof(e2);
-    e2.full.key.index = 1;
-    t.header.size += sizeof(e2);
+    size_t i = 0, entry_offset = 0;
+    uint32_t k = 0;
+    for (auto const& v : values) {
+        if (short_offsets) {
+            uint16_t *p = reinterpret_cast<uint16_t *>(p_offsets) + i;
+            *p = v ? (entry_offset >> 2) & 0xffffu : 0xffffu;
+        } else {
+            uint32_t *p = reinterpret_cast<uint32_t *>(p_offsets) + i;
+            *p = v ? entry_offset : ResTable_type::NO_ENTRY;
+        }
 
-    Res_value v2;
-    memset(&v2, 0, sizeof(v2));
-    t.header.size += sizeof(v2);
-
-    uint8_t* data = (uint8_t*)malloc(t.header.size);
-    uint8_t* p = data;
-    memcpy(p, &t, sizeof(t));
-    p += sizeof(t);
-    memcpy(p, offsets, sizeof(offsets));
-    p += sizeof(offsets);
-    memcpy(p, &e1, sizeof(e1));
-    p += sizeof(e1);
-    memcpy(p, &v1, sizeof(v1));
-    p += sizeof(v1);
-    memcpy(p, &e2, sizeof(e2));
-    p += sizeof(e2);
-    memcpy(p, &v2, sizeof(v2));
-    p += sizeof(v2);
-    return data;
+        if (v) {
+            ResTable_entry entry{};
+            if (compact_entry) {
+                entry.compact.key = i;
+                entry.compact.flags = ResTable_entry::FLAG_COMPACT | (v->dataType << 8);
+                entry.compact.data = v->data;
+                memcpy(p_entries, &entry, sizeof(entry)); p_entries += sizeof(entry);
+                entry_offset += sizeof(entry);
+            } else {
+                Res_value value{};
+                entry.full.size = sizeof(entry);
+                entry.full.key.index = i;
+                value = *v;
+                memcpy(p_entries, &entry, sizeof(entry)); p_entries += sizeof(entry);
+                memcpy(p_entries, &value, sizeof(value)); p_entries += sizeof(value);
+                entry_offset += sizeof(entry) + sizeof(value);
+            }
+        }
+        i++;
+    }
+    return reinterpret_cast<ResTable_type*>(data);
 }
 
 TEST(TypeVariantIteratorTest, shouldIterateOverTypeWithoutErrors) {
-    ResTable_type* data = (ResTable_type*) createTypeData();
+    std::vector<Res_value *> values;
 
-    TypeVariant v(data);
+    Res_value *v1 = new Res_value{};
+    values.push_back(v1);
 
-    TypeVariant::iterator iter = v.beginEntries();
-    ASSERT_EQ(uint32_t(0), iter.index());
-    ASSERT_TRUE(NULL != *iter);
-    ASSERT_EQ(uint32_t(0), iter->full.key.index);
-    ASSERT_NE(v.endEntries(), iter);
+    values.push_back(nullptr);
 
-    iter++;
+    Res_value *v2 = new Res_value{};
+    values.push_back(v2);
 
-    ASSERT_EQ(uint32_t(1), iter.index());
-    ASSERT_TRUE(NULL == *iter);
-    ASSERT_NE(v.endEntries(), iter);
+    Res_value *v3 = new Res_value{ sizeof(Res_value), 0, Res_value::TYPE_STRING, 0x12345678};
+    values.push_back(v3);
 
-    iter++;
+    // test for combinations of compact_entry and short_offsets
+    for (size_t i = 0; i < 4; i++) {
+        bool compact_entry = i & 0x1, short_offsets = i & 0x2;
+        ResTable_type* data = createTypeTable(values, compact_entry, short_offsets);
+        TypeVariant v(data);
 
-    ASSERT_EQ(uint32_t(2), iter.index());
-    ASSERT_TRUE(NULL != *iter);
-    ASSERT_EQ(uint32_t(1), iter->full.key.index);
-    ASSERT_NE(v.endEntries(), iter);
+        TypeVariant::iterator iter = v.beginEntries();
+        ASSERT_EQ(uint32_t(0), iter.index());
+        ASSERT_TRUE(NULL != *iter);
+        ASSERT_EQ(uint32_t(0), iter->key());
+        ASSERT_NE(v.endEntries(), iter);
 
-    iter++;
+        iter++;
 
-    ASSERT_EQ(v.endEntries(), iter);
+        ASSERT_EQ(uint32_t(1), iter.index());
+        ASSERT_TRUE(NULL == *iter);
+        ASSERT_NE(v.endEntries(), iter);
 
-    free(data);
+        iter++;
+
+        ASSERT_EQ(uint32_t(2), iter.index());
+        ASSERT_TRUE(NULL != *iter);
+        ASSERT_EQ(uint32_t(2), iter->key());
+        ASSERT_NE(v.endEntries(), iter);
+
+        iter++;
+
+        ASSERT_EQ(uint32_t(3), iter.index());
+        ASSERT_TRUE(NULL != *iter);
+        ASSERT_EQ(iter->is_compact(), compact_entry);
+        ASSERT_EQ(uint32_t(3), iter->key());
+        ASSERT_EQ(uint32_t(0x12345678), iter->value().data);
+        ASSERT_EQ(Res_value::TYPE_STRING, iter->value().dataType);
+
+        iter++;
+
+        ASSERT_EQ(v.endEntries(), iter);
+
+        free(data);
+    }
 }
 
 } // namespace android