Add processing of external file entries.

Also added some unit level comments.

Signed-off-by: Graeme Geldenhuys <graemeg@gmail.com>

4 files changed, 78 insertions, 7 deletions

diff --git a/src/docdump/docdump.lpi b/src/docdump/docdump.lpi
index 182a9da4..9ed376e4 100644
--- a/src/docdump/docdump.lpi
+++ b/src/docdump/docdump.lpi
@@ -23,7 +23,7 @@
         <LaunchingApplication PathPlusParams="/usr/X11R6/bin/xterm -T 'Lazarus Run Output' -e $(LazarusDir)/tools/runwait.sh $(TargetCmdLine)"/>
       </local>
     </RunParams>
-    <Units Count="5">
+    <Units Count="7">
       <Unit0>
         <Filename Value="docdump.lpr"/>
         <IsPartOfProject Value="True"/>
@@ -49,6 +49,15 @@
         <IsPartOfProject Value="True"/>
         <UnitName Value="filestreamhelper"/>
       </Unit4>
+      <Unit5>
+        <Filename Value="readextfiles.pas"/>
+        <IsPartOfProject Value="True"/>
+        <UnitName Value="readextfiles"/>
+      </Unit5>
+      <Unit6>
+        <Filename Value="../../docs/inf04.txt"/>
+        <IsPartOfProject Value="True"/>
+      </Unit6>
     </Units>
   </ProjectOptions>
   <CompilerOptions>
diff --git a/src/docdump/docdump.lpr b/src/docdump/docdump.lpr
index 4415a0a8..6596578f 100644
--- a/src/docdump/docdump.lpr
+++ b/src/docdump/docdump.lpr
@@ -1,3 +1,6 @@
+{
+  Dumps the structure of an OS/2 IPF help file
+}
 program docdump;
 
 {$mode objfpc}{$H+}
@@ -7,7 +10,7 @@ uses
   cthreads,
   {$ENDIF}{$ENDIF}
   Classes, SysUtils, IPFFileFormatUnit, IPFEscapeCodes, CustApp, readheader,
-  filestreamhelper;
+  filestreamhelper, readextfiles;
 
 type
 
@@ -51,6 +54,7 @@ begin
   try
     FOut.WriteLn(Format('File name: %s (%d bytes)', [ExtractFileName(ParamStr(1)), FIn.Size]));
     ProcessHeader(FIn, FOut);
+    ProcessExtFiles(FIn, FOut);
   finally
     FIn.Free;
     FOut.Free;
@@ -79,6 +83,7 @@ end;
 var
   Application: TDocDump;
 
+
 begin
   Application:=TDocDump.Create(nil);
   Application.Run;
diff --git a/src/docdump/readextfiles.pas b/src/docdump/readextfiles.pas
new file mode 100644
index 00000000..6ea979d9
--- /dev/null
+++ b/src/docdump/readextfiles.pas
@@ -0,0 +1,53 @@
+{
+  Dumps the names of external database (help) files referenced by this file
+}
+unit readextfiles;
+
+{$mode objfpc}{$H+}
+
+interface
+
+uses
+  Classes, SysUtils, IPFFileFormatUnit, filestreamhelper;
+
+procedure ProcessExtFiles(AIn: TFileStream; AOut: TFileTextStream);
+
+
+implementation
+
+uses
+  readheader;
+
+procedure ProcessExtFiles(AIn: TFileStream; AOut: TFileTextStream);
+var
+  count: integer;
+  name: string;
+  pData: pointer;
+  p: pointer;
+  pLength: pByte;
+begin
+  AOut.WriteLn('');
+  AOut.WriteLn('External File References');
+
+  if eHdr.NumDataBase > 0 then
+  begin
+    pData := nil;
+    AIn.Seek(eHdr.DataBaseOffset, soBeginning);
+    GetMem(pData, eHdr.DataBaseSize);     // allocate temp space for data
+    AIn.Read(pData^, eHdr.DataBaseSize);  // read all data in one shot
+    p := pData; // p is our incrementing position in the data
+    for count := 0 to eHdr.NumDataBase-1 do
+    begin
+      pLength := p;       // length byte, including itself
+      SetString(name, p+1, pLength^-1);   // use length value minus the length byte to get the string length
+      AOut.WriteLn(Format('  File #%d: %s', [count, name]));
+      inc(p, pLength^);   // skip to next entry using full length (including length byte)
+    end;
+    FreeMem(pData, eHdr.DataBaseSize);    // free allocated space
+  end
+  else
+    AOut.WriteLn('  No external file references found');
+end;
+
+end.
+
diff --git a/src/docdump/readheader.pas b/src/docdump/readheader.pas
index 30f090dc..3f220368 100644
--- a/src/docdump/readheader.pas
+++ b/src/docdump/readheader.pas
@@ -1,3 +1,6 @@
+{
+  Dump the INF header & extended header structures to a text file
+}
 unit readheader;
 
 {$mode objfpc}{$H+}
@@ -5,14 +8,17 @@ unit readheader;
 interface
 
 uses
-  Classes, SysUtils, filestreamhelper;
+  Classes, SysUtils, filestreamhelper, IPFFileFormatUnit;
 
 procedure ProcessHeader(AIn: TFileStream; AOut: TFileTextStream);
 
+var
+  hdr: THelpFileHeader;
+  eHdr: TExtendedHelpFileHeader;
+
+
 implementation
 
-uses
-  IPFFileFormatUnit;
 
 type
   TWord = record
@@ -36,8 +42,6 @@ type
 
 procedure ProcessHeader(AIn: TFileStream; AOut: TFileTextStream);
 var
-  hdr: THelpFileHeader;
-  eHdr: TExtendedHelpFileHeader;
   bytes: integer;
   s: string;
   w: TWord;