1 files changed, 59 insertions, 0 deletions
diff --git a/libs/esptk/src/subrecord.cpp b/libs/esptk/src/subrecord.cpp
new file mode 100644
index 0000000..cb3890a
--- /dev/null
+++ b/libs/esptk/src/subrecord.cpp
@@ -0,0 +1,59 @@
+#include "subrecord.h"
+#include "espexceptions.h"
+#include "esptypes.h"
+#include <cstdint>
+#include <cstring>
+#include <string>
+#include <unordered_map>
+
+ESP::SubRecord::SubRecord() : m_Type(TYPE_UNKNOWN), m_Data() {}
+
+bool ESP::SubRecord::readFrom(std::istream& stream, uint32_t sizeOverride)
+{
+  static std::unordered_map<std::string, EType> s_TypeMap{{"HEDR", TYPE_HEDR},
+                                                          {"CNAM", TYPE_CNAM},
+                                                          {"MAST", TYPE_MAST},
+                                                          {"ONAM", TYPE_ONAM},
+                                                          {"SNAM", TYPE_SNAM}};
+
+  char typeString[5];
+  if (!stream.read(typeString, 4)) {
+    if (stream.gcount() == 0) {
+      return false;
+    } else {
+      throw ESP::InvalidRecordException("sub-record incomplete (unknown type)");
+    }
+  }
+  if (stream.gcount() != 4) {
+    throw ESP::InvalidRecordException(
+        std::string("sub-record type incomplete (invalid type ") + typeString + ")");
+  }
+  typeString[4] = '\0';  // not sure if this is required, shouldn't be
+  auto iter     = s_TypeMap.find(std::string(typeString));
+  if (iter != s_TypeMap.end()) {
+    m_Type = iter->second;
+  } else if (strncmp(typeString, "XXXX", 4) == 0) {
+    if (readType<uint16_t>(stream) != 4) {
+      throw ESP::InvalidRecordException(
+          "XXXX record is supposed to be 4 bytes in size");
+    }
+    return readFrom(stream, readType<uint32_t>(stream));
+  } else {
+    m_Type = TYPE_UNKNOWN;
+  }
+
+  uint32_t dataSize = readType<uint16_t>(stream);
+  if (sizeOverride != 0UL) {
+    dataSize = sizeOverride;
+  }
+  m_Data.resize(dataSize);
+
+  if (dataSize > 0) {
+    stream.read(reinterpret_cast<char*>(m_Data.data()), dataSize);
+  }
+  if (!stream) {
+    throw ESP::InvalidRecordException(std::string("sub-record incomplete: ") +
+                                      typeString);
+  }
+  return true;
+}