Implement a simple utility method to extract the components of an IPv4 address.

source/Library/Utils.cpp

@@ -1,15 +1,97 @@
 // ------------------------------------------------------------------------------------------------
 #include "Library/Utils.hpp"
 
+// ------------------------------------------------------------------------------------------------
+#include <cstdio>
+#include <cstdlib>
+
 // ------------------------------------------------------------------------------------------------
 namespace SqMod {
 
 // ------------------------------------------------------------------------------------------------
 extern void Register_Buffer(HSQUIRRELVM vm);
 
+/* ------------------------------------------------------------------------------------------------
+ * Probably not the best implementation but should cover all sorts of weird cases.
+*/
+static SQInteger SqExtractIPv4(HSQUIRRELVM vm)
+{
+    // Was the IP address specified?
+    if (sq_gettop(vm) <= 1)
+    {
+        return sq_throwerror(vm, "Missing IP address string");
+    }
+    // Attempt to generate the string value
+    StackStrF val(vm, 2);
+    // Have we failed to retrieve the string?
+    if (SQ_FAILED(val.mRes))
+    {
+        return val.mRes; // Propagate the error!
+    }
+    // Cleansed IP address buffer
+    SQChar address[16] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
+    // Counting variables used by loops
+    Uint32 i = 0, j = 0, k = 0;
+    // Replicate the necessary characters from the resulted string
+    for (; (i < static_cast< Uint32 >(val.mLen)) && (j < 16) && (k < 4); ++i)
+    {
+        // Is this a digit?
+        if (std::isdigit(val.mPtr[i]) != 0)
+        {
+            address[j++] = val.mPtr[i]; // Just replicate it
+        }
+        // Is this a delimiter?
+        else if (val.mPtr[i] == '.')
+        {
+            // Add a dummy component if one was not specified
+            if (j == 0 || address[j-1] == '.')
+            {
+                address[j++] = '0';
+            }
+            // Add the actual delimiter
+            address[j++] = '.';
+            // Increase the block counter
+            ++k;
+        }
+    }
+    // Complete the address if it wasn't (also count the last block)
+    while (++k < 4)
+    {
+        address[j++] = '0';
+        address[j++] = '.';
+    }
+    // Components of the IP address
+    Uint32 blocks[4] = {0, 0, 0, 0};
+    // Attempt to extract the components of the IP address
+    std::sscanf(address, "%u.%u.%u.%u", &blocks[0], &blocks[1], &blocks[2], &blocks[3]);
+    // Create a new array on the stack to hold the extracted components
+    sq_newarray(vm, 4);
+    // Push the elements into the array
+    for (i = 0; i < 4; ++i)
+    {
+        // Push the element index
+        sq_pushinteger(vm, i);
+        // Push the element value
+        sq_pushinteger(vm, Clamp(blocks[i], 0U, 255U));
+        // Assign the element
+        const SQRESULT res = sq_set(vm, -3);
+        // See if the assignment failed
+        if (SQ_FAILED(res))
+        {
+            return res;
+        }
+    }
+    // Specify that we have a result on the stack
+    return 1;
+}
+
 // ================================================================================================
 void Register_Utils(HSQUIRRELVM vm)
 {
+    RootTable(vm).Bind(_SC("SqUtils"), Table(vm)
+        .SquirrelFunc(_SC("ExtractIPv4"), &SqExtractIPv4)
+    );
+
     Register_Buffer(vm);
 }