Version 2.2

Include/StrStr.nsh

@@ -0,0 +1,62 @@
+!define StrStr "!insertmacro StrStr"
+
+!macro StrStr ResultVar String SubString
+  Push `${String}`
+  Push `${SubString}`
+  Call StrStr
+  Pop `${ResultVar}`
+!macroend
+
+Function StrStr
+/*After this point:
+  ------------------------------------------
+  $R0 = SubString (input)
+  $R1 = String (input)
+  $R2 = SubStringLen (temp)
+  $R3 = StrLen (temp)
+  $R4 = StartCharPos (temp)
+  $R5 = TempStr (temp)*/
+
+  ;Get input from user
+  Exch $R0
+  Exch
+  Exch $R1
+  Push $R2
+  Push $R3
+  Push $R4
+  Push $R5
+
+  ;Get "String" and "SubString" length
+  StrLen $R2 $R0
+  StrLen $R3 $R1
+  ;Start "StartCharPos" counter
+  StrCpy $R4 0
+
+  ;Loop until "SubString" is found or "String" reaches its end
+  ${Do}
+    ;Remove everything before and after the searched part ("TempStr")
+    StrCpy $R5 $R1 $R2 $R4
+
+    ;Compare "TempStr" with "SubString"
+    ${IfThen} $R5 == $R0 ${|} ${ExitDo} ${|}
+    ;If not "SubString", this could be "String"'s end
+    ${IfThen} $R4 >= $R3 ${|} ${ExitDo} ${|}
+    ;If not, continue the loop
+    IntOp $R4 $R4 + 1
+  ${Loop}
+
+/*After this point:
+  ------------------------------------------
+  $R0 = ResultVar (output)*/
+
+  ;Remove part before "SubString" on "String" (if there has one)
+  StrCpy $R0 $R1 `` $R4
+
+  ;Return output to user
+  Pop $R5
+  Pop $R4
+  Pop $R3
+  Pop $R2
+  Pop $R1
+  Exch $R0
+FunctionEnd