Implemented VT_Read(), added stub UTF32 output support, also made WriteUTF8() to...

[tpg/acess2.git] / Kernel / lib.c

diff --git a/Kernel/lib.c b/Kernel/lib.c
index ee9f24e..c8a0e9f 100644 (file)
--- a/Kernel/lib.c
+++ b/Kernel/lib.c
@@ -168,6 +168,8 @@ int strpos8(char *str, Uint32 Search)
  */
 int ReadUTF8(Uint8 *str, Uint32 *Val)
 {
+       *Val = 0xFFFD;  // Assume invalid character
+       
        // ASCII
        if( !(*str & 0x80) ) {
                *Val = *str;
@@ -176,7 +178,6 @@ int ReadUTF8(Uint8 *str, Uint32 *Val)
        
        // Middle of a sequence
        if( (*str & 0xC0) == 0x80 ) {
-               *Val = -1;
                return 1;
        }
        
@@ -217,10 +218,55 @@ int ReadUTF8(Uint8 *str, Uint32 *Val)
        }
        
        // UTF-8 Doesn't support more than four bytes
-       *Val = -1;
        return 4;
 }
 
+/**
+ * \fn int WriteUTF8(Uint8 *str, Uint32 Val)
+ * \brief Write a UTF-8 character sequence to a string
+ */
+int WriteUTF8(Uint8 *str, Uint32 Val)
+{
+       // ASCII
+       if( Val < 128 ) {
+               *str = Val;
+               return 1;
+       }
+       
+       // Two Byte
+       if( Val < 0x8000 ) {
+               *str = 0xC0 | (Val >> 6);
+               str ++;
+               *str = 0x80 | (Val & 0x3F);
+               return 2;
+       }
+       
+       // Three Byte
+       if( Val < 0x10000 ) {
+               *str = 0xE0 | (Val >> 12);
+               str ++;
+               *str = 0x80 | ((Val >> 6) & 0x3F);
+               str ++;
+               *str = 0x80 | (Val & 0x3F);
+               return 3;
+       }
+       
+       // Four Byte
+       if( Val < 0x110000 ) {
+               *str = 0xF0 | (Val >> 18);
+               str ++;
+               *str = 0x80 | ((Val >> 12) & 0x3F);
+               str ++;
+               *str = 0x80 | ((Val >> 6) & 0x3F);
+               str ++;
+               *str = 0x80 | (Val & 0x3F);
+               return 4;
+       }
+       
+       // UTF-8 Doesn't support more than four bytes
+       return 0;
+}
+
 /**
  * \fn Uint64 timestamp(int sec, int mins, int hrs, int day, int month, int year)
  * \brief Converts a date into an Acess Timestamp