VPatch 2.1:

* Added argument checking and error handling to GenPat. Now returns exit codes as well to indicate success/failure (and the reason for failure). Only GenPat has changed in this version compared to 2.0 final.
* Bug Fix: GenPat no longer gives an Access Violation when attempting to patch a file smaller than 64 bytes into a file larger than 64 bytes.


git-svn-id: https://svn.code.sf.net/p/nsis/code/NSIS/trunk@3318 212acab6-be3b-0410-9dea-997c60f758d6

Contrib/VPatch/Readme.html

@@ -103,29 +103,32 @@ a:hover
         <h1>VPatch 2</h1>
         <div> 
           <h2>Introduction</h2>
-<p>VPatch allows to create a patch file to update previous versions of your software. The GenPat
+          <p>VPatch allows to create a patch file to update previous versions 
-utitily generates the patch file. The plug-in can use the patch to update a file. Using a patch,
+            of your software. The GenPat utitily generates the patch file. The 
-you can reduce the download size of your updates, because only the differences between the files
+            plug-in can use the patch to update a file. Using a patch, you can 
-are included in the patch file.</p>
+            reduce the download size of your updates, because only the differences 
+            between the files are included in the patch file.</p>
           <h2>How to use</h2>
           <h3>Generate the patch file</h3>
-<p>Make sure you have the source file (original version) and the target file (version to update
+          <p>Make sure you have the source file (original version) and the target 
-to). For example, DATA.DTA (currently on user system) and DATA_20.DTA (version 2.0 of this data
+            file (version to update to). For example, DATA.DTA (currently on user 
-file). Now call the command line tool GenPat.exe:</p>
+            system) and DATA_20.DTA (version 2.0 of this data file). Now call 
+            the command line tool GenPat.exe:</p>
           <pre>
 GENPAT data.dta data_20.dta data.pat
 </pre>
           <p>Now, the patch will be generated, this will take some time.</p>
-<p>Using the /B=(BlockSize) parameter of the GenPat utility (put it after the filenames), you can
+          <p>Using the /B=(BlockSize) parameter of the GenPat utility (put it 
-use a different block size. A smaller block size may result in a smaller patch, but the generation
+            after the filenames), you can use a different block size. A smaller 
-will take more time (the default blocksize is 64).</p>
+            block size may result in a smaller patch, but the generation will 
+            take more time (the default blocksize is 64).</p>
           <h3>Update the file during installation</h3>
           <p>Use the VPatch plug-in to update a file using a patch file:</p>
           <pre>
 vpatch::vpatchfile "pathfile.pat" "source.file" "new.file"
 </pre>
-<p>The result of the patch operating will be added to the stack and can be one of the following
+          <p>The result of the patch operating will be added to the stack and 
-texts:</p>
+            can be one of the following texts:</p>
           <ul>
             <li>OK</li>
             <li>OK, new version already installed</li>
@@ -135,38 +138,109 @@ texts:</p>
           </ul>
           <p>Check <a href="example.nsi">example.nsi</a> for an example.</p>
           <h3>Multiple patches in one file</h3>
-<p>GenPat appends a patch to the file you specified. If there is already a patch for the same
+          <p>GenPat appends a patch to the file you specified. If there is already 
-orginal file in the patch file, the patch will be replaced. For example, if you want to be able to
+            a patch for the same orginal file in the patch file, the patch will 
-upgrade version 1 and 2 to version 3, you can put a 1 &gt; 3 and 2 &gt; 3 patch in one file.</p>
+            be replaced. For example, if you want to be able to upgrade version 
-<p>You can also put patches for different files in one patch file, for example, a patch from file A
+            1 and 2 to version 3, you can put a 1 &gt; 3 and 2 &gt; 3 patch in 
-version 1 to file A version 2 and a patch from file B version 1 to file B version 2. Just call the
+            one file.</p>
-plug-in multiple times with the same patch file. It will automatically select the right patch
+          <p>You can also put patches for different files in one patch file, for 
-(based on the file CRC).</p>
+            example, a patch from file A version 1 to file A version 2 and a patch 
+            from file B version 1 to file B version 2. Just call the plug-in multiple 
+            times with the same patch file. It will automatically select the right 
+            patch (based on the file CRC).</p>
+          <h3>GenPat exit codes</h3>
+          <p>In version 2.1 support was added for exit codes (known as error levels 
+            in the DOS period) to GenPat. GenPat will return an exit code based 
+            on succes of the patch generation. Here is a list of the possible 
+            exit codes:</p>
+          <table width="547" border="0" cellspacing="0" cellpadding="0">
+            <tr> 
+              <td><b>Exit code</b></td>
+              <td><b>Description</b></td>
+            </tr>
+            <tr> 
+              <td>0</td>
+              <td>Success</td>
+            </tr>
+            <tr> 
+              <td>1</td>
+              <td>Arguments missing</td>
+            </tr>
+            <tr> 
+              <td>2</td>
+              <td>Source file not found</td>
+            </tr>
+            <tr> 
+              <td>3</td>
+              <td>Target file not found</td>
+            </tr>
+            <tr> 
+              <td>4</td>
+              <td>Unknown error while reading existing patch file</td>
+            </tr>
+            <tr> 
+              <td>5</td>
+              <td>Unknown error while generating patch</td>
+            </tr>
+            <tr> 
+              <td>6</td>
+              <td>Unknown error while writing patch file to disk</td>
+            </tr>
+            <tr> 
+              <td>10</td>
+              <td>CRC of source and target file are equal</td>
+            </tr>
+            <tr> 
+              <td>11</td>
+              <td>Not enough memory for source file</td>
+            </tr>
+			<tr> 
+              <td>12</td>
+              <td>Not enough memory for target file</td>
+            </tr>
+          </table>
+          <p>These exit codes can be useful when you generate patch files through 
+            a script.</p>
+        </div>
+        <div>
           <h2>Source code</h2>
           <h3>NSIS plug-in (C++)</h3>
-<p>The source of the NSIS plug-in that applies patches can be found in the Source\Plugin
+          <p>The source of the NSIS plug-in that applies patches can be found 
-folder.</p>
+            in the Source\Plugin folder.</p>
           <h3>Patch Generator (Delphi)</h3>
-<p>The most interesting part of VPatch, the actual patch generation algoritm, can be found in
+          <p>The most interesting part of VPatch, the actual patch generation 
-Source\GenPat\PatchGenerator.pas. The header of that file contains a brief explanation of the
+            algoritm, can be found in Source\GenPat\PatchGenerator.pas. The header 
-algoritm as well.</p>
+            of that file contains a brief explanation of the algoritm as well.</p>
           <h3>User interface (Delphi)</h3>
-<p>A user interface is included as well, which you will have to build yourself because the GUI
+          <p>A user interface is included as well, which you will have to build 
-executable was too large to include. Besides Borland Delphi 6 or higher (you can use the freely
+            yourself because the GUI executable was too large to include. Besides 
-available Personal edition), you will also need to install the <a href=
+            Borland Delphi 6 or higher (you can use the freely available Personal 
+            edition), you will also need to install the <a href=
 "http://www.delphi-gems.com">VirtualTreeView</a> component by Mike Lischke.</p>
           <h2>Version history</h2>
           <ul>
+            <li>2.1 
+              <ul>
+                <li>Added argument checking and error handling to GenPat. Now 
+                  returns exit codes as well to indicate success/failure (and 
+                  the reason for failure). Only GenPat has changed in this version 
+                  compared to 2.0 final.</li>
+                <li>Bug Fix: GenPat no longer gives an Access Violation when attempting 
+                  to patch a file smaller than 64 bytes into a file larger than 
+                  64 bytes.</li>
+              </ul>
+            </li>
             <li>2.0 final 
               <ul>
-<li>Cleaned up source code for the patch generator, which is now included (this code is written in
+                <li>Cleaned up source code for the patch generator, which is now 
-Borland Delphi 6 and compiles with the freely available Personal edition).</li>
+                  included (this code is written in Borland Delphi 6 and compiles 
+                  with the freely available Personal edition).</li>
               </ul>
             </li>
             <li>2.0 beta 2 
               <ul>
-<li>All new algorithm used in the patch generator: much faster (up to 90%) while using smaller
+                <li>All new algorithm used in the patch generator: much faster 
-block sizes (higher compression)</li>
+                  (up to 90%) while using smaller block sizes (higher compression)</li>
                 <li>Created a NSIS 2 plugin</li>
                 <li>Works with small files</li>
                 <li>Replaces existing patch in file if original file CRC is identical</li>
@@ -196,7 +270,8 @@ it freely, subject to the following restrictions:
 2. Altered versions must be plainly marked as such,
    and must not be misrepresented as being the original software.
 3. This notice may not be removed or altered from any distribution.
-</pre></div>
+</pre>
+        </div>
       </td>
 </tr>
 </table>

Contrib/VPatch/Source/GenPat/GenPat2.dpr

@@ -11,6 +11,9 @@ program GenPat2;
 
   What's new
   ----------
+  2.1   20031219    Koen            Added error checking, handling, shouldn't
+                                    crash when invalid arguments, returns
+                                    exit codes now.
   2.0   20030811    Koen            Initial documentation
 }
 
@@ -38,18 +41,20 @@ type
 var
   Config: TextFile;
   T1,T2: TDateTime;
-  d: Integer;
+  d, i: Integer;
   S,Key: String;
-  ShowDebug: Boolean;
+  SourceFile, TargetFile, PatchFile: String;
+  ShowDebug, ShowHelp: Boolean;
   PG: TPatchGenerator;
   EV: TEventHandler;
+
 begin
   EV:=TEventHandler.Create;
   PG:=TPatchGenerator.Create;
   PG.StartBlockSize:=64;
 
-  WriteLn('GenPat v2.0 final');
+  WriteLn('GenPat v2.1');
-  WriteLn('=================');
+  WriteLn('===========');
   WriteLn;
   WriteLn('(c) 2001-2003 Van de Sande Productions');
   WriteLn('Website: http://www.tibed.net/vpatch');
@@ -75,13 +80,35 @@ begin
     CloseFile(Config);
   end;
 {$ENDIF}
+  i:=0;
   for d:=1 to ParamCount do begin
     if CompareStr(LowerCase(Copy(ParamStr(d),1,3)),'/b=')=0 then begin
       PG.StartBlockSize:=StrToInt(Copy(ParamStr(d),4,10));
+    end else begin
+      // not a parameter?
+      if not (ParamStr(d)[1] = '/') then begin
+        if i = 2 then begin
+          PatchFile:=ParamStr(d);
+          Inc(i);
+        end;
+        if i = 1 then begin
+          TargetFile:=ParamStr(d);
+          Inc(i);
+        end;
+        if i = 0 then begin
+          SourceFile:=ParamStr(d);
+          Inc(i);
+        end;
+      end;
     end;
   end;
 
-  if (CompareStr(ParamStr(1),'')=0) or (CompareStr(ParamStr(2),'')=0) or (CompareStr(ParamStr(3),'')=0) then begin
+  ShowHelp:=False;
+  if(CompareStr(PatchFile,'')=0) then ShowHelp:=True;
+  if SourceFile = '' then ShowHelp:=True;
+  if TargetFile = '' then ShowHelp:=True;
+
+  if ShowHelp then begin
     WriteLn('This program will take (sourcefile) as input and create a (patchfile).');
     WriteLn('With this patchfile, you can convert a (sourcefile) into (targetfile).');
     WriteLn;
@@ -90,36 +117,110 @@ begin
     WriteLn;
     WriteLn('Command line options (you do not need them):');
     WriteLn('/B=(BlockSize)             Set blocksize (def=64), multiple of 2');
-    WriteLn('/WAIT                      Wait for a keypress after program complete');
+    WriteLn('/NOEQUALERROR              Exit code becomes 0 instead of 10 when');
+    WriteLn('                           two files with equal CRC are encountered');
+    WriteLn('                           (patch file will remain unchanged)');
     WriteLn('/DEBUG                     Show runtime debug information');
-    WriteLn('Note: all these parameters must be *after* the filenames!');
     WriteLn;
-    Write('Press a enter to exit ');
+    WriteLn('Note: filenames should never start with / character!');
-    ReadLn(S);
+    WriteLn;
+    WriteLn('Possible exit codes:');
+    WriteLn('  0  Success');
+    WriteLn('  1  Arguments missing');
+    WriteLn('  2  Source file not found');
+    WriteLn('  3  Target file not found');
+    WriteLn('  4  Unknown error while reading existing patch file');
+    WriteLn('  5  Unknown error while generating patch');
+    WriteLn('  6  Unknown error while writing patch file to disk');
+    WriteLn('  10 CRC of source and target file are equal (impossible with /NOEQUALERROR)');
+    WriteLn('  11 Not enough memory for source file');
+    WriteLn('  12 Not enough memory for target file');
+    PG.Free;
+    ExitCode:=1;
     Exit;
   end;
 
-  if FileExists(ParamStr(3)) then begin
+  // stop if file error, result shown above
-    WriteLn('Using existing file to include patches in: '+ParamStr(3));
+  if not FileExists(SourceFile) then begin
-    PG.LoadFromFile(ParamStr(3));
+    WriteLn('Error: Source file not found');
+    PG.Free;
+    ExitCode:=2;
+    Exit;
   end;
+  if not FileExists(TargetFile) then begin
+    WriteLn('Error: Target file not found');
+    PG.Free;
+    ExitCode:=3;
+    Exit;
+  end;
+
+  if FileExists(PatchFile) then begin
+    WriteLn('Using existing file to include patches in: '+PatchFile);
+    try
+      PG.LoadFromFile(PatchFile);
+    except
+      on E: Exception do begin
+        WriteLn('Error: Reading existing patch file failed');
+        WriteLn('Error message: ', E.ClassName, ': ', E.Message);
+        PG.Free;
+        ExitCode:=4;
+        Exit;
+      end;
+    end;
+  end;
+
+  WriteLn('Source (original) file: ', SourceFile);
+  WriteLn('Target (newer) file:    ', TargetFile);
 
   T1:=Now;
-  WriteLn('Patch body size: '+IntToStr(PG.CreatePatch(ParamStr(1),ParamStr(2))));
+
-  PG.WriteToFile(ParamStr(3));
+  // create patch file, with error handling
+  try
+    i:=PG.CreatePatch(SourceFile,TargetFile);
+  except
+    on E: Exception do begin
+      WriteLn('Error: Generating patch failed');
+      WriteLn('Error message: ', E.ClassName, ': ', E.Message);
+      PG.Free;
+      ExitCode:=5;
+      Exit;
+    end;
+  end;
+
+  if(i < 0) then begin
+    if(i = -1) then begin
+      if not FindCmdLineSwitch('noequalerror',['/'],True) then
+        WriteLn('Error: CRC of source and target file are equal');
+    end;
+    if(i = -2) then WriteLn('Error: Not enough memory for source file');
+    if(i = -3) then WriteLn('Error: Not enough memory for target file');
+    ExitCode:=9 - i;
+
+    if(i = -1) and (FindCmdLineSwitch('noequalerror',['/'],True)) then begin
+      WriteLn('Equal CRCs ignored (no patch will be written and exit code is 0)');
+      ExitCode:=0;
+    end;
+  end else begin
+    WriteLn('Patch body size: '+IntToStr(i));
+    try
+      PG.WriteToFile(PatchFile);
+    except
+      on E: Exception do begin
+        WriteLn('Error: Writing patch to file ' + PatchFile + ' failed');
+        WriteLn('Error message: ', E.ClassName, ': ', E.Message);
+        PG.Free;
+        ExitCode:=6;
+        Exit;
+      end;
+    end;
 
     T2:=Now;
-  Write('GenPat.exe finished execution in: ');
+    Write('Time taken for generation: ');
     WriteLn(FloatToStr((T2-T1)*24*60*60),'s');
     WriteLn;
-{$IFNDEF AUTOWAIT}
+
-  if FindCmdLineSwitch('wait',['/'],True) then begin
+    ExitCode:=0;
-{$ENDIF}
-    WriteLn;
-    WriteLn('Press a key');
-    ReadLn(S);
-{$IFNDEF AUTOWAIT}
   end;
-{$ENDIF}
+
   PG.Free;
 end.

Contrib/VPatch/Source/GenPat/PatchGenerator.pas

@@ -32,6 +32,8 @@ unit PatchGenerator;
 
   What's new
   ----------
+  2.1   20031219    Koen            Added error checking to CreatePatch, returns
+                                    negative numbers when there are errors.
   2.0   20030811    Koen            Initial documentation
 }
 
@@ -141,8 +143,8 @@ var
   retTO: Integer;
   noN: Integer;
 begin
-  fsSource:=TFileStream.Create(SourceFileName,fmOpenRead);
+  fsSource:=TFileStream.Create(SourceFileName,fmOpenRead+fmShareDenyNone);
-  fsTarget:=TFileStream.Create(TargetFileName,fmOpenRead);
+  fsTarget:=TFileStream.Create(TargetFileName,fmOpenRead+fmShareDenyNone);
   fm:=TMemoryStream.Create;
 
   SetLength(PRay,INIT_BLOCK_COUNT);
@@ -150,7 +152,14 @@ begin
 
   //Load those files into memory!
   SourceSize:=fsSource.Size;
+  try
     GetMem(Source,SourceSize);
+  except
+    on EOutOfMemory do begin
+      Result:=-2;           // not enough memory for source file
+      Exit;
+    end;
+  end;
   fm.CopyFrom(fsSource,SourceSize);
   Move(fm.Memory^,Source^,SourceSize);
   SourceCRC:=FileCRC(fsSource);
@@ -158,13 +167,28 @@ begin
 
   fm.Clear;
   TargetSize:=fsTarget.Size;
+  try
     GetMem(Target,TargetSize);
+  except
+    on EOutOfMemory do begin
+      FreeMem(Source,SourceSize);
+      Result:=-3;           // not enough memory for target file
+      Exit;
+    end;
+  end;
   fm.CopyFrom(fsTarget,TargetSize);
   Move(fm.Memory^,Target^,TargetSize);
   TargetCRC:=FileCRC(fsTarget);
   fsTarget.Free;
   fm.Free;
 
+  if(SourceCRC = TargetCRC) then begin
+    FreeMem(Source,SourceSize);
+    FreeMem(Target,TargetSize);
+    Result:=-1;
+    Exit;
+  end;
+
   PRay[0].TargetOffset:=0;
   PRay[0].SourceOffset:=0;
   PRay[0].Size:=0;

Contrib/VPatch/Source/GenPat/TreeCode.pas

@@ -15,6 +15,8 @@ unit TreeCode;
 
   What's new
   ----------
+  2.1   20031219    Koen            Fixed bug in TreeFind: when tree was a nil
+                                    pointer, now returns instead of AVing
   2.0   20030811    Koen            Initial documentation
 }
 
@@ -179,6 +181,10 @@ var
   lo,mid,hi,m: Integer;
   tmp: Cardinal;
 begin
+  if not Assigned(ABlockTree) then begin
+    FoundCount:=0; Result:=nil;
+    Exit;
+  end;
   lo:=0;
   hi:=ABlockTreeNodeCount-1;
   while true do begin