Revision 0:fbac423fa3d4, committed 2013-03-07

Comitter:

sam_grove

Date:

Thu Mar 07 21:38:29 2013 +0000

Child:

1:c590c304b2fa

Commit message:

Cleaned up documentation and updated example

Changed in this revision

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/atoh.cpp	Thu Mar 07 21:38:29 2013 +0000
@@ -0,0 +1,71 @@
+/**
+ * @file   atoh.cpp
+ * @brief  Convert an ASCII hex string to hexadecimal - seems like the 
+ *  std library should include this... maybe it does. Just couldn't find it
+ * @author  sam grove
+ * @version 1.0
+ *
+ * Copyright (c) 2013
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+ 
+#include "atoh.h"
+
+template<typename T>
+T atoh( char const *string )
+{
+    T value = 0;
+    char ch = 0;
+    uint8_t digit = 0, bail = sizeof(T) << 1;
+    
+    // loop until the string has ended
+    while ( ( ch = *(string++) ) != 0 ) 
+    {
+        // service digits 0 - 9
+        if ( ( ch >= '0' ) && ( ch <= '9' ) ) 
+        {
+            digit = ch - '0';
+        }
+        // and then lowercase a - f
+        else if ( ( ch >= 'a' ) && ( ch <= 'f' ) ) 
+        {
+            digit = ch - 'a' + 10;
+        }
+        // and uppercase A - F
+        else if ( ( ch >= 'A' ) && ( ch <= 'F' ) ) 
+        {
+            digit = ch - 'A' + 10;
+        }
+        // stopping where we are if an inapproprate value is found
+        else 
+        {
+            break;
+        }
+        // if the return is 8, 16, or 32 bits - only parse that amount
+        if ( bail-- == 0 )
+        {
+            break;
+        }
+        // and build the value now, preparing for the next pass
+        value = (value << 4) + digit;
+    }
+
+    return value;
+}
+
+template uint8_t  atoh <uint8_t> (const char* string );
+template uint16_t atoh <uint16_t>(const char* string );
+template uint32_t atoh <uint32_t>(const char* string );
+template uint64_t atoh <uint64_t>(const char* string );
+

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/atoh.h	Thu Mar 07 21:38:29 2013 +0000
@@ -0,0 +1,57 @@
+/**
+ * @file   atoh.h
+ * @brief  Convert an ASCII hex string to hexadecimal - seems like the 
+ *  std library should include this... maybe it does. Just couldn't find it
+ * @author  sam grove
+ * @version 1.0
+ *
+ * Copyright (c) 2013
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+ 
+#ifndef ATOH_H
+#define ATOH_H
+
+#include <stdint.h>
+
+/** Convert a ASCII string to it's binary equivenent
+ *
+ * Example:
+ * @code
+ *  #include "mbed.h"
+ *  #include "atoh.h"
+ * 
+ *  int main()
+ *  {
+ *      uint64_t result = atoh <uint64_t> ("0123456789abcdef" );
+ *      uint32_t lo = result & 0x00000000ffffffff;
+ *      uint32_t hi = (result >> 32);
+ *      printf( "0x%08X%08X\n", hi, lo );
+ *      printf( "0x%08X\n", atoh <uint32_t> ( "12345678" ) );
+ *      printf( "0x%04X\n", atoh <uint16_t> ( "1234" ) );
+ *      printf( "0x%02X\n", atoh <uint8_t> ( "12" ) );
+ *  }
+ * @endcode
+ */
+
+/** A templated method for ascii to hex conversions. Supported types are:
+ *  uint8_t, uint16_t, uint32_t and uint64_t
+ *  @param string - An ascii string of hex digits
+ *  @returns The binary equivelant of the string
+ */
+template<typename T>
+T atoh( char const *string );
+
+#endif
+