share/WinGit/environment.inc.iss

   1 [Code]
   2
   3 // Returns the value(s) of the environment variable "VarName", which is tokenized
   4 // by ";" into an array of strings. This makes it easy query PATH-like variables
   5 // in addition to normal variables. If "AllUsers" is true, the common variables
   6 // are searched, else the user-specific ones.
   7 function GetEnvStrings(VarName:string;AllUsers:Boolean):TArrayOfString;
   8 var
   9     Path:string;
  10     i:Longint;
  11     p:Integer;
  12 begin
  13     Path:='';
  14
  15     // See http://www.jrsoftware.org/isfaq.php#env
  16     if AllUsers then begin
  17         // We ignore errors here. The resulting array of strings will be empty.
  18         RegQueryStringValue(HKEY_LOCAL_MACHINE,'SYSTEM\CurrentControlSet\Control\Session Manager\Environment',VarName,Path);
  19     end else begin
  20         // We ignore errors here. The resulting array of strings will be empty.
  21         RegQueryStringValue(HKEY_CURRENT_USER,'Environment',VarName,Path);
  22     end;
  23
  24     // Fallback for built-in variables which are not stored in the Registry.
  25     if Length(Path)=0 then begin
  26         Path:=ExpandConstant('{%'+VarName+'}');
  27     end;
  28
  29     // Make sure we have at least one semicolon.
  30     Path:=Path+';';
  31
  32     // Split the directories in PATH into an array of strings.
  33     i:=0;
  34     SetArrayLength(Result,0);
  35
  36     p:=Pos(';',Path);
  37     while p>0 do begin
  38         SetArrayLength(Result,i+1);
  39         if p>1 then begin
  40             Result[i]:=Copy(Path,1,p-1);
  41             i:=i+1;
  42         end;
  43         Path:=Copy(Path,p+1,Length(Path));
  44         p:=Pos(';',Path);
  45     end;
  46 end;
  47
  48 // Sets the contents of the specified environment variable for the current process.
  49 function SetEnvironmentVariable(lpName,lpValue:String):Boolean;
  50 #ifdef UNICODE
  51 external 'SetEnvironmentVariableW@Kernel32.dll stdcall delayload';
  52 #else
  53 external 'SetEnvironmentVariableA@Kernel32.dll stdcall delayload';
  54 #endif
  55
  56 // Sets the environment variable "VarName" to the concatenation of "DirStrings"
  57 // using ";" as the delimiter. If "AllUsers" is true, a common variable is set,
  58 // else a user-specific one. If "DeleteIfEmpty" is true and "DirStrings" is
  59 // empty, "VarName" is deleted instead of set if it exists.
  60 function SetEnvStrings(VarName:string;AllUsers,DeleteIfEmpty:Boolean;DirStrings:TArrayOfString):Boolean;
  61 var
  62     Path,KeyName:string;
  63     i:Longint;
  64 begin
  65     // Merge all non-empty directory strings into a PATH variable.
  66     Path:='';
  67     for i:=0 to GetArrayLength(DirStrings)-1 do begin
  68         if Length(DirStrings[i])>0 then begin
  69             if Length(Path)>0 then begin
  70                 Path:=Path+';'+DirStrings[i];
  71             end else begin
  72                 Path:=DirStrings[i];
  73             end;
  74         end;
  75     end;
  76
  77     // See http://www.jrsoftware.org/isfaq.php#env
  78     if AllUsers then begin
  79         KeyName:='SYSTEM\CurrentControlSet\Control\Session Manager\Environment';
  80         if DeleteIfEmpty and (Length(Path)=0) then begin
  81             Result:=(not RegValueExists(HKEY_LOCAL_MACHINE,KeyName,VarName)) or
  82                          RegDeleteValue(HKEY_LOCAL_MACHINE,KeyName,VarName);
  83         end else begin
  84             Result:=RegWriteStringValue(HKEY_LOCAL_MACHINE,KeyName,VarName,Path);
  85         end;
  86     end else begin
  87         KeyName:='Environment';
  88         if DeleteIfEmpty and (Length(Path)=0) then begin
  89             Result:=(not RegValueExists(HKEY_CURRENT_USER,KeyName,VarName)) or
  90                          RegDeleteValue(HKEY_CURRENT_USER,KeyName,VarName);
  91         end else begin
  92             Result:=RegWriteStringValue(HKEY_CURRENT_USER,KeyName,VarName,Path);
  93         end;
  94     end;
  95
  96     // Also update the environment of the current process.
  97     SetEnvironmentVariable(VarName,Path);
  98 end;