Creating and unsing symlinks for Python executables on Android

Former-commit-id: 33d5eb4

Author: lmbelo

src/Embeddable/PyEnvironment.Embeddable.pas

@@ -68,6 +68,7 @@ TPyCustomEmbeddableDistribution = class(TPyDistribution)
  {$IFDEF POSIX}
  function FileIsExecutable(const AFilePath: string): boolean;
  {$ENDIF POSIX}
+ procedure CreateSymlink(const ASymlink, ATarget: string);
  protected
  function EnvironmentExists(): boolean;
  /// <summary>
@@ -79,6 +80,7 @@ TPyCustomEmbeddableDistribution = class(TPyDistribution)
  /// An embeddable distribution will be used as an "image".
  /// </summary>
  procedure CreateEnvironment(const ACancelation: ICancelation); virtual;
+ procedure CreateSymLinks(); virtual;
  procedure LoadSettings(const ACancelation: ICancelation); virtual;
  protected
  function GetEnvironmentPath(): string;
@@ -167,11 +169,12 @@ implementation
  System.IOUtils,
  System.Character,
  System.StrUtils,
+ System.RegularExpressions,
  PyTools.ExecCmd,
  PyEnvironment.Exception,
  PyEnvironment.Path
  {$IFDEF POSIX}
- , Posix.SysStat, Posix.Stdlib, Posix.String_, Posix.Errno
+ , Posix.SysStat, Posix.Stdlib, Posix.String_, Posix.Errno, Posix.Unistd
  {$ENDIF}
  ;
 
@@ -207,6 +210,52 @@ procedure TPyCustomEmbeddableDistribution.CreateEnvironment(const ACancelation:
  end;
 end;
 
+procedure TPyCustomEmbeddableDistribution.CreateSymlink(const ASymlink,
+ ATarget: string);
+var
+ LExistingTarget: string;
+begin
+ LExistingTarget := String.Empty;
+ if TFile.Exists(ATarget) then begin
+ //There is a bug with TFile.Exists and TFile.GetSymLinkTarget for Android
+ //So we recreate it every time
+ DeleteFile(ASymlink);
+
+ if not TFile.CreateSymLink(ASymlink, ATarget) then
+ raise ESymlinkFailed.CreateFmt('Failed to create the symlink: %s -> %s', [ASymlink, ATarget]);
+ end;
+end;
+
+procedure TPyCustomEmbeddableDistribution.CreateSymLinks;
+var
+ LTargetInterpreter: string;
+ LTargetLauncher: string;
+ LSymlinkInterpreter: string;
+ LSynlinkLauncher: string;
+begin
+ {$IFNDEF ANDROID}
+ Exit;
+ {$ENDIF ANDROID}
+ //Real file names
+ LTargetInterpreter := TPath.Combine(
+ TPath.GetLibraryPath(),
+ String.Format('libpython%s.so', [PythonVersion]));
+ LTargetLauncher := TPath.Combine(
+ TPath.GetLibraryPath(),
+ String.Format('libpythonlauncher%s.so', [PythonVersion]));
+ //Symlink names
+ LSymlinkInterpreter := TPath.Combine(
+ TPath.Combine(GetEnvironmentPath(), 'lib'),
+ String.Format('libpython%s.so', [PythonVersion]));
+ LSynlinkLauncher := TPath.Combine(
+ TPath.Combine(GetEnvironmentPath(), 'bin'),
+ String.Format('python%s', [PythonVersion]));
+ //Creates the interpreter symlink
+ CreateSymlink(LSymlinkInterpreter, LTargetInterpreter);
+ //Creates the launcher symlink
+ CreateSymlink(LSynlinkLauncher, LTargetLauncher);
+end;
+
 procedure TPyCustomEmbeddableDistribution.DoZipProgressEvt(Sender: TObject; FileName: string;
  Header: TZipHeader; Position: Int64);
 begin
@@ -247,8 +296,10 @@ function TPyCustomEmbeddableDistribution.FindExecutable: string;
  begin
  Result := TDirectory.GetFiles(APath, 'python*', TSearchOption.soTopDirectoryOnly,
  function(const Path: string; const SearchRec: TSearchRec): boolean
+ var
+ LFileName: string;
  begin
- var LFileName: string := SearchRec.Name;
+ LFileName := SearchRec.Name;
  if LFileName.EndsWith('m') then //3.7 and lower contain a "m" as sufix.
  LFileName := LFileName.Remove(Length(LFileName) - 1);
 
@@ -274,14 +325,6 @@ function TPyCustomEmbeddableDistribution.FindExecutable: string;
  Exit(Result)
  else
  Exit(String.Empty);
- {$ELSEIF DEFINED(ANDROID)}
- //Let's try it in the library path first
- //we should place it in the library path in Android
- Result := TPath.GetLibraryPath();
- LFiles := DoSearch(Result);
- if LFiles <> nil then
- Exit(LFiles[Low(LFiles)]);
- Result := TPath.Combine(GetEnvironmentPath(), 'bin');
  {$ELSE}
  Result := TPath.Combine(GetEnvironmentPath(), 'bin');
  {$ENDIF}
@@ -303,14 +346,14 @@ function TPyCustomEmbeddableDistribution.FindSharedLibrary: string;
  LSearch: string;
  begin
  LFile := TPath.Combine(APath, ALibName);
- if not TFile.Exists(LFile) then begin
- LSearch := ALibName.Replace(TPath.GetExtension(ALibName), '') + '*' + TPath.GetExtension(ALibName);
- Result := TDirectory.GetFiles(
-  APath,
-  LSearch, //Python <= 3.7 might contain a "m" as sufix.
-  TSearchOption.soTopDirectoryOnly);
- end else
- Result := [LFile];
+ if TFile.Exists(LFile) then
+ Exit(TArray<string>.Create(LFile));
+
+ LSearch := ALibName.Replace(TPath.GetExtension(ALibName), '') + '*' + TPath.GetExtension(ALibName);
+ Result := TDirectory.GetFiles(
+ APath,
+  LSearch, //Python <= 3.7 might contain a "m" as sufix.
+ TSearchOption.soTopDirectoryOnly);
  end;
 
 var
@@ -327,14 +370,6 @@ function TPyCustomEmbeddableDistribution.FindSharedLibrary: string;
 
  {$IFDEF MSWINDOWS}
  LPath := GetEnvironmentPath();
- {$ELSEIF DEFINED(ANDROID)}
- //Let's try it in the library path first - we should place it in the library path in Android
- LPath := TPath.GetLibraryPath();
- LFiles := DoSearch(LLibName, LPath);
- if LFiles <> nil then
- Exit(LFiles[Low(LFiles)]);
- //Try to find it in the environment folder
- LPath := TPath.Combine(GetEnvironmentPath(), 'lib');
  {$ELSEIF DEFINED(MACOS)}
  //Let's try it in the library path first
  LPath := TPyEnvironmentPath.ResolvePath(TPyEnvironmentPath.ENVIRONMENT_PATH);
@@ -385,6 +420,8 @@ function TPyCustomEmbeddableDistribution.Setup(const ACancelation: ICancelation)
  CreateEnvironment(ACancelation);
  end;
 
+ CreateSymLinks();
+
  LoadSettings(ACancelation);
 
  Result := true;