FIX #1680: Internal Viewer crashes on macOS

in FPC 3.2.2, there are some bugs in Iconvert().
use the fixed Iconvert() instead of the FPC version on macOS.

components/doublecmd/dcconvertencoding.pas

@@ -68,11 +68,11 @@ implementation
 
 uses
   {$IF DEFINED(UNIX)}
-  iconvenc_dyn, LazUTF8
+  LazUTF8
     {$IF DEFINED(DARWIN)}
-    , MacOSAll, CocoaAll, StrUtils
+    , dc_iconvenc_dyn, MacOSAll, CocoaAll, StrUtils
     {$ELSE}
-    , UnixCP
+    , iconvenc_dyn, UnixCP
     {$ENDIF}
   {$ELSEIF DEFINED(MSWINDOWS)}
   Windows

components/doublecmd/doublecmd_common.lpk

@@ -8,6 +8,8 @@
       <Version Value="11"/>
       <PathDelim Value="\"/>
       <SearchPaths>
+        <IncludeFiles Value="iconvenc"/>
+        <OtherUnitFiles Value="iconvenc"/>
         <UnitOutputDirectory Value="lib\$(TargetCPU)-$(TargetOS)"/>
       </SearchPaths>
       <Conditionals Value="if (TargetCPU &lt;> &apos;arm&apos;) then
@@ -35,7 +37,7 @@ end"/>
     <Description Value="Common units for Double Commander"/>
     <License Value="GNU GPL 2"/>
     <Version Minor="4" Release="1"/>
-    <Files Count="12">
+    <Files Count="14">
       <Item1>
         <Filename Value="dcclassesutf8.pas"/>
         <UnitName Value="DCClassesUtf8"/>
@@ -84,6 +86,14 @@ end"/>
         <Filename Value="dcjsonconfig.pas"/>
         <UnitName Value="DCJsonConfig"/>
       </Item12>
+      <Item13>
+        <Filename Value="iconvenc\dc_iconvert.inc"/>
+        <Type Value="Include"/>
+      </Item13>
+      <Item14>
+        <Filename Value="iconvenc\dc_iconvenc_dyn.pas"/>
+        <UnitName Value="dc_iconvenc_dyn"/>
+      </Item14>
     </Files>
     <CompatibilityMode Value="True"/>
     <RequiredPkgs Count="2">

components/doublecmd/doublecmd_common.pas

@@ -1,17 +1,17 @@
-{ This file was automatically created by Lazarus. Do not edit!
-  This source is only used to compile and install the package.
- }
-
-unit doublecmd_common;
-
-{$warn 5023 off : no warning about unused units}
-interface
-
-uses
-  DCClassesUtf8, DCOSUtils, DCStrUtils, DCBasicTypes, DCFileAttributes, 
-  DCConvertEncoding, DCDateTimeUtils, DCXmlConfig, DCProcessUtf8, 
-  DCUnicodeUtils, DCStringHashListUtf8, DCJsonConfig;
-
-implementation
-
-end.
+{ This file was automatically created by Lazarus. Do not edit!
+  This source is only used to compile and install the package.
+ }
+
+unit doublecmd_common;
+
+{$warn 5023 off : no warning about unused units}
+interface
+
+uses
+  DCClassesUtf8, DCOSUtils, DCStrUtils, DCBasicTypes, DCFileAttributes, 
+  DCConvertEncoding, DCDateTimeUtils, DCXmlConfig, DCProcessUtf8, 
+  DCUnicodeUtils, DCStringHashListUtf8, DCJsonConfig, dc_iconvenc_dyn;
+
+implementation
+
+end.

components/doublecmd/iconvenc/dc_iconvenc_dyn.pas

@@ -0,0 +1,106 @@
+{
+    This file is part of the Free Pascal run time library.
+    Copyright (c) 2000 by Marco van de Voort(marco@freepascal.org)
+    member of the Free Pascal development team
+
+    libiconv header translation + a helper routine
+    http://wiki.freepascal.org/iconvenc Dynamic version
+
+    See the file COPYING.FPC, included in this distribution,
+    for details about the copyright. (LGPL)
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+
+}
+unit dc_iconvenc_dyn;
+
+interface
+{$mode objfpc}{$H+}
+
+uses
+  ctypes,unixtype,baseunix,
+  dl,
+  initc;
+
+const
+  n = 1;
+
+{$ifdef beos}
+  ESysEILSEQ = EILSEQ;
+{$endif}
+
+type
+   piconv_t = ^iconv_t;
+   iconv_t = pointer;
+
+   Ticonv_open = function(__tocode: pchar; __fromcode: pchar): iconv_t; cdecl;
+   Ticonv = function(__cd: iconv_t; __inbuf: ppchar; __inbytesleft: psize_t; __outbuf: ppchar; __outbytesleft: psize_t): size_t; cdecl;
+   Ticonv_close = function(__cd: iconv_t): cint; cdecl;
+
+var
+  iconv_lib: pointer;
+  iconv_open: Ticonv_open;
+  iconv: Ticonv;
+  iconv_close: Ticonv_close;
+  IconvLibFound: boolean = False;
+
+function TryLoadLib(LibName: string; var error: string): boolean; // can be used to load non standard libname
+function Iconvert(s: string; var res: string; const FromEncoding, ToEncoding: string): cint;
+function InitIconv(var error: string): boolean;
+
+implementation
+
+function TryLoadLib(LibName: string; var error: string): boolean;
+
+    function resolvesymbol (var funcptr; symbol: string): Boolean;
+    begin
+      pointer(funcptr) := pointer(dlsym(iconv_lib, pchar(symbol)));
+      result := assigned(pointer(funcptr));
+      if not result then
+        error := error+#13#10+dlerror();
+    end;
+
+var
+  res: boolean;
+begin
+  result := false;
+  Error := Error+#13#10'Trying '+LibName;
+  iconv_lib := dlopen(pchar(libname), RTLD_NOW);
+  if Assigned(iconv_lib) then
+  begin
+    result := true;
+    result := result and resolvesymbol(pointer(iconv),'iconv');
+    result := result and resolvesymbol(pointer(iconv_open),'iconv_open');
+    result := result and resolvesymbol(pointer(iconv_close),'iconv_close');
+    if not result then
+      begin
+        result:=true;
+        result := result and resolvesymbol(pointer(iconv),'libiconv');
+        result := result and resolvesymbol(pointer(iconv_open),'libiconv_open');
+        result := result and resolvesymbol(pointer(iconv_close),'libiconv_close');
+      end;
+//    if not res then
+//      dlclose(iconv_lib);
+  end else
+    error:=error+#13#10+dlerror();
+end;
+
+
+function InitIconv(var error: string): boolean;
+begin
+  result := true;
+  error := '';
+  if not TryLoadLib('libc.so.6', error) then
+    if not TryLoadLib('libiconv.so', error) then
+    {$if defined(haiku)}
+        if not TryLoadLib('libtextencoding.so', error) then
+      {$ifend}
+      result := false;
+  iconvlibfound := iconvlibfound or result;
+end;
+
+{$i dc_iconvert.inc}
+
+end.

components/doublecmd/iconvenc/dc_iconvert.inc

@@ -0,0 +1,53 @@
+function Iconvert(S: string; var Res: string; const FromEncoding, ToEncoding: string): cint;
+var
+  InLen, OutLen, Offset: size_t;
+  Src, Dst: pchar;
+  H: iconv_t;
+  lerr: cint;
+  iconvres: size_t;
+begin
+  H := iconv_open(PChar(ToEncoding), PChar(FromEncoding));
+  if h=Iconv_t(-1) then
+  begin
+    Res := S;
+    exit(-1);
+  end;
+
+  try
+    InLen:=Length(s);
+    outlen:=InLen;
+    setlength(res,outlen);
+
+    Src := PChar(S);
+    Dst := PChar(Res);
+
+    while InLen > 0 do
+    begin
+      iconvres := iconv(H, @Src, @InLen, @Dst, @OutLen);
+      if iconvres = size_t(-1) then
+      begin
+        lerr := cerrno;
+        if lerr = ESysEILSEQ then // unknown char, skip
+          begin
+            Inc(Src);
+            Dec(InLen);
+          end
+        else
+          if lerr = ESysE2BIG then
+            begin
+              Offset := Dst - PChar(Res);
+              SetLength(Res, Length(Res)+InLen*2+5); // 5 is minimally one utf-8 char
+              Dst := PChar(Res) + Offset;
+              OutLen := Length(Res) - Offset;
+            end
+          else
+            exit(-1)
+      end;
+    end;
+  finally
+    setlength(Res,Length(Res) - Outlen);
+    iconv_close(H);
+  end;
+
+  Result := 0;
+end;