Restructured AMS data parsing

src/ams/Cosem.h

@@ -0,0 +1,92 @@
+#ifndef _COSEM_H
+#define _COSEM_H
+
+#include "lwip/def.h"
+
+// Blue book, Table 2
+enum CosemType {
+    CosemTypeNull = 0x00,
+    CosemTypeArray = 0x01,
+    CosemTypeStructure = 0x02,
+    CosemTypeOctetString = 0x09,
+    CosemTypeString = 0x0A,
+    CosemTypeDLongSigned = 0x05,
+    CosemTypeDLongUnsigned = 0x06,
+    CosemTypeLongSigned = 0x10,
+    CosemTypeLongUnsigned = 0x12,
+    CosemTypeLong64Signed = 0x14,
+    CosemTypeLong64Unsigned = 0x15,
+    CosemTypeDateTime = 0x19
+};
+
+struct CosemBasic {
+    uint8_t type;
+    uint8_t length;
+} __attribute__((packed));
+
+struct CosemString {
+    uint8_t type;
+    uint8_t length;
+    uint8_t data[];
+} __attribute__((packed));
+
+struct CosemLongSigned {
+    uint8_t type;
+	int16_t data;
+} __attribute__((packed));
+
+struct CosemLongUnsigned {
+    uint8_t type;
+    uint16_t data;
+} __attribute__((packed));
+
+struct CosemDLongSigned {
+    uint8_t type;
+    int32_t data;
+} __attribute__((packed));
+
+struct CosemDLongUnsigned {
+    uint8_t type;
+    uint32_t data;
+} __attribute__((packed));
+
+struct CosemLong64Signed {
+    uint8_t type;
+    int64_t data;
+} __attribute__((packed));
+
+struct CosemLong64Unsigned {
+    uint8_t type;
+    uint64_t data;
+} __attribute__((packed));
+
+struct CosemDateTime {
+    uint8_t type;
+    uint16_t year;
+    uint8_t month;
+    uint8_t dayOfMonth;
+    uint8_t dayOfWeek;
+    uint8_t hour;
+    uint8_t minute;
+    uint8_t second;
+    uint8_t hundredths;
+    int16_t deviation;
+    uint8_t status;
+} __attribute__((packed));
+
+typedef union {
+    struct CosemBasic base;
+	struct CosemString str;
+	struct CosemString oct;
+    struct CosemLongSigned ls;
+	struct CosemLongUnsigned lu;
+    struct CosemDLongSigned dls;
+    struct CosemDLongUnsigned dlu;
+    struct CosemLong64Signed l64s;
+    struct CosemLong64Unsigned l64u;
+    struct CosemDateTime dt;
+} CosemData; 
+
+time_t decodeCosemDateTime(CosemDateTime timestamp);
+
+#endif