Merge pull request #10 from tboudreaux/spec/OPAT

src/opatIO/private/opatIO.cpp

@@ -11,6 +11,26 @@
 #include <limits>
 #include <deque>
 
+// Function to check system endianness
+bool is_big_endian() {
+    uint16_t test = 0x1;
+    return reinterpret_cast<uint8_t*>(&test)[0] == 0;
+}
+
+// Generic function to swap bytes for any type
+template <typename T>
+T swap_bytes(T value) {
+    static_assert(std::is_trivially_copyable<T>::value, "swap_bytes only supports trivial types.");
+    T result;
+    uint8_t* src = reinterpret_cast<uint8_t*>(&value);
+    uint8_t* dest = reinterpret_cast<uint8_t*>(&result);
+    for (size_t i = 0; i < sizeof(T); i++) {
+        dest[i] = src[sizeof(T) - 1 - i];
+    }
+    return result;
+}
+
+
 // Constructor
 OpatIO::OpatIO() {}
 
@@ -57,6 +77,12 @@ void OpatIO::readHeader(std::ifstream &file) {
     if (file.gcount() != sizeof(Header)) {
         throw std::runtime_error("Error reading header from file: " + filename);
     }
+
+    if (is_big_endian()) {
+        header.version = swap_bytes(header.version);
+        header.numTables = swap_bytes(header.numTables);
+        header.indexOffset = swap_bytes(header.indexOffset);
+    }
 }
 
 // Read the table index from the file
@@ -67,6 +93,7 @@ void OpatIO::readTableIndex(std::ifstream &file) {
     if (file.gcount() != static_cast<std::streamsize>(header.numTables * sizeof(TableIndex))) {
         throw std::runtime_error("Error reading table index from file: " + filename);
     }
+
     buildTableIDToComposition();
 }
 

src/opatIO/public/opatIO.h

@@ -9,6 +9,7 @@
 #include <map>
 #include <utility>
 
+#pragma pack(1)
 struct Header {
     char magic[4];
     uint16_t version;
@@ -21,6 +22,7 @@ struct Header {
     char reserved[26]; 
 };
 
+#pragma pack()
 struct TableIndex {
     double X;
     double Z;

tests/opatIO/opatIOTest.cpp

@@ -6,7 +6,7 @@
 #include <set>
 #include <sstream>
 
-std::string EXAMPLE_FILENAME = std::string(getenv("MESON_SOURCE_ROOT")) + "/tests/opatIO/example.opat";
+std::string EXAMPLE_FILENAME = std::string(getenv("MESON_SOURCE_ROOT")) + "/tests/opatIO/test.opat";
 
 /**
  * @file opatIOTest.cpp
@@ -39,9 +39,9 @@ TEST_F(opatIOTest, Header) {
     EXPECT_EQ(header.numTables, 20);
     EXPECT_EQ(header.headerSize, 256);
     EXPECT_EQ(header.indexOffset, 416416);
-    EXPECT_EQ(std::string(header.creationDate), "Feb 14, 2025");
+    EXPECT_EQ(std::string(header.creationDate), "Feb 16, 2025");
-    EXPECT_EQ(std::string(header.sourceInfo), "MESA 12700, Synthetic Opacity Data");
+    EXPECT_EQ(std::string(header.sourceInfo), "no source provided by user");
-    EXPECT_EQ(std::string(header.comment), "log10 kappa (cm^2/g)");
+    EXPECT_EQ(std::string(header.comment), "default header");
 }
 
 TEST_F(opatIOTest, TableIndex) {

utils/opatio/src/opatio/opat/opat.py

@@ -186,6 +186,87 @@ class OpatIO:
         
         return tableIndexBytes
 
+    def __repr__(self) -> str:
+        reprString = f"""OpatIO(
+  versoion: {self.header.version}
+  numTables: {self.header.numTables}
+  headerSize: {self.header.headerSize}
+  indexOffset: {self.header.indexOffset}
+  creationDate: {self.header.creationDate}
+  sourceInfo: {self.header.sourceInfo}
+  comment: {self.header.comment}
+  reserved: {self.header.reserved}
+)"""
+        return reprString
+
+    def _format_table_as_string(self, table: OPATTable, X: float, Z: float) -> str:
+        tableString: List[str] = []
+        # fixed width X and Z header per table
+        tableString.append(f"X: {X:<10.4f} Z: {Z:<10.4f}")
+        tableString.append("-" * 80)
+        # write logR accross the top (reserving one col for where logT will be)
+        logRRow = f"{"":<10}"
+        logRRowTrue = "".join(f"{r:<10.4f}" for r in table.logR)
+        tableString.append(logRRow + logRRowTrue)
+        for i, logT in enumerate(table.logT):
+            row = f"{logT:<10.4f}"
+            for kappa in table.logKappa[i]:
+                row += f"{kappa:<10.4f}"
+            tableString.append(row)
+        tableString.append("=" * 80)
+        return '\n'.join(tableString)
+
+    @staticmethod
+    def print_table_indexes(table_indexes: List[TableIndex]) -> str:
+        if not table_indexes:
+            print("No table indexes found.")
+            return
+
+        tableRows: List[str] = []
+        tableRows.append("\nTable Indexes in OPAT File:\n")
+        tableRows.append(f"{'X':<10} {'Z':<10} {'Byte Start':<15} {'Byte End':<15} {'Checksum (SHA-256)'}")
+        tableRows.append("=" * 80)
+        for entry in table_indexes:
+            tableRows.append(f"{entry.X:<10.4f} {entry.Z:<10.4f} {entry.byteStart:<15} {entry.byteEnd:<15} {entry.sha256[:16]}...")
+        return '\n'.join(tableRows)
+
+    def save_as_ascii(self, filename: str) -> str:
+        numericFMT = "{:.18e}"
+        currentStartByte: int = 256
+        tableIndexs: List[bytes] = []
+        tableStrings: List[bytes] = []
+        for (X, Z), table in self.tables:
+            checksum, tableBytes = self._table_bytes(table)
+            tableStrings.append(self._format_table_as_string(table, X, Z) + "\n")
+            tableIndex = TableIndex(
+                X = X,
+                Z = Z,
+                byteStart = currentStartByte,
+                byteEnd = currentStartByte + len(tableBytes),
+                sha256 = checksum
+            )
+            tableIndexs.append(tableIndex)
+            
+
+            currentStartByte += len(tableBytes)
+        self.header.indexOffset = currentStartByte
+        with open(filename, 'w') as f:
+            f.write(f"{self.header.magic}\n")
+            f.write(f"Version: {self.header.version}\n")
+            f.write(f"numTables: {self.header.numTables}\n")
+            f.write(f"headerSize (bytes): {self.header.headerSize}\n")
+            f.write(f"tableIndex Offset (bytes): {self.header.indexOffset}\n")
+            f.write(f"Creation Date: {self.header.creationDate}\n")
+            f.write(f"Source Info: {self.header.sourceInfo}\n")
+            f.write(f"Comment: {self.header.comment}\n")
+            f.write("="*80 + "\n")
+            f.write("="*80 + "\n")
+            for tableString in tableStrings:
+                f.write(tableString)
+                f.write("="*80 + "\n")
+            f.write("="*80 + "\n")
+            f.write(self.print_table_indexes(tableIndexs))
+
     def save(self, filename: str) -> str:
         tempHeaderBytes = self._header_bytes()
 
@@ -229,14 +310,14 @@ def loadOpat(filename: str) -> OpatIO:
         headerBytes: bytes = f.read(256)
         unpackedHeader = struct.unpack("<4s H I I Q 16s 64s 128s 26s", headerBytes)
         loadedHeader = Header(
-            magic = unpackedHeader[0].decode(),
+            magic = unpackedHeader[0].decode().replace("\x00", ""),
             version = unpackedHeader[1],
             numTables = unpackedHeader[2],
             headerSize = unpackedHeader[3],
             indexOffset = unpackedHeader[4],
-            creationDate = unpackedHeader[5].decode(),
+            creationDate = unpackedHeader[5].decode().replace("\x00", ""),
-            sourceInfo = unpackedHeader[6].decode(),
+            sourceInfo = unpackedHeader[6].decode().replace("\x00", ""),
-            comment = unpackedHeader[7].decode(),
+            comment = unpackedHeader[7].decode().replace("\x00", ""),
             reserved = unpackedHeader[8]
         )
         opat.header = loadedHeader