Add OutputGzipFile

lib/streams.gd

@@ -726,14 +726,16 @@ DeclareOperation( "OutputTextString", [ IsList, IsBool ] );
 ##  <#GAPDoc Label="OutputTextFile">
 ##  <ManSection>
 ##  <Oper Name="OutputTextFile" Arg='filename, append'/>
+##  <Oper Name="OutputGzipFile" Arg='filename, append'/>
 ##
 ##  <Description>
 ##  <C>OutputTextFile( <A>filename</A>, <A>append</A> )</C> returns an output stream in the
 ##  category <C>IsOutputTextFile</C> that writes received characters to the file
 ##  <A>filename</A>.  If <A>append</A> is <K>false</K>, then the file is emptied first,
 ##  otherwise received characters are added at the end of the file.
 ##  If <A>filename</A> ends in <C>.gz</C> then the file will be
-##  written with gzip compression.
+##  written with gzip compression. <C>OutputGzipFile</C> acts identically to
+##  <C>OutputTextFile</C>, except it compresses the output with gzip.
 ##  <P/>
 ##  <Example><![CDATA[
 ##  gap> # use a temporary directory
@@ -766,6 +768,7 @@ DeclareOperation( "OutputTextString", [ IsList, IsBool ] );
 ##  <#/GAPDoc>
 ##
 DeclareOperation( "OutputTextFile", [ IsString, IsBool ] );
+DeclareOperation( "OutputGzipFile", [ IsString, IsBool ] );
 
 
 #############################################################################

lib/streams.gi

@@ -1084,14 +1084,33 @@ fi;
 #M  OutputTextFile( <str>, <append> )
 ##
 InstallMethod( OutputTextFile,
-    "output text stream from file",
+    "output text stream to file",
     [ IsString,
       IsBool ],
 function( str, append )
     local   fid;
     str := UserHomeExpand(str);
 
-    fid := OUTPUT_TEXT_FILE( str, append );
+    fid := OUTPUT_TEXT_FILE( str, append, false );
+    if fid = fail  then
+        return fail;
+    else
+        atomic OutputTextFileStillOpen do
+            AddSet( OutputTextFileStillOpen, fid );
+        od;
+        return Objectify( OutputTextFileType, [fid, Immutable(str), true] );
+    fi;
+end );
+
+InstallMethod( OutputGzipFile,
+    "output gzipped text to file",
+    [ IsString,
+      IsBool ],
+function( str, append )
+    local   fid;
+    str := UserHomeExpand(str);
+
+    fid := OUTPUT_TEXT_FILE( str, append, true );
     if fid = fail  then
         return fail;
     else
@@ -1110,6 +1129,14 @@ InstallOtherMethod( OutputTextFile,
     Error("Usage OutputTextFile( <fname>, <append> )");
 end );
 
+InstallOtherMethod( OutputGzipFile,
+        "error catching method, append not given",
+        [ IsString ],
+        -SUM_FLAGS, # as low as possible
+        function( str )
+    Error("Usage OutputGzipFile( <fname>, <append> )");
+end );
+
 #############################################################################
 ##
 #M  CloseStream( <output-text-file> )

src/io.c

@@ -360,7 +360,7 @@ UInt OpenInput(TypInputFile * input, const Char * filename)
 #endif
 
     /* try to open the input file                                          */
-    file = SyFopen( filename, "r" );
+    file = SyFopen(filename, "r", TRUE);
     if ( file == -1 )
         return 0;
 
@@ -503,7 +503,7 @@ UInt OpenLog (
         return 0;
 
     /* try to open the file                                                */
-    IO()->OutputLogFileOrStream.file = SyFopen(filename, "w");
+    IO()->OutputLogFileOrStream.file = SyFopen(filename, "w", TRUE);
     IO()->OutputLogFileOrStream.isstream = FALSE;
     if (IO()->OutputLogFileOrStream.file == -1)
         return 0;
@@ -597,7 +597,7 @@ UInt OpenInputLog (
         return 0;
 
     /* try to open the file                                                */
-    IO()->InputLogFileOrStream.file = SyFopen(filename, "w");
+    IO()->InputLogFileOrStream.file = SyFopen(filename, "w", TRUE);
     IO()->InputLogFileOrStream.isstream = FALSE;
     if (IO()->InputLogFileOrStream.file == -1)
         return 0;
@@ -694,7 +694,7 @@ UInt OpenOutputLog (
     /* try to open the file                                                */
     memset(&IO()->OutputLogFileOrStream, 0, sizeof(TypOutputFile));
     IO()->OutputLogFileOrStream.isstream = FALSE;
-    IO()->OutputLogFileOrStream.file = SyFopen(filename, "w");
+    IO()->OutputLogFileOrStream.file = SyFopen(filename, "w", TRUE);
     if (IO()->OutputLogFileOrStream.file == -1)
         return 0;
 
@@ -817,7 +817,7 @@ UInt OpenOutput(TypOutputFile * output, const Char * filename, BOOL append)
 #endif
 
     /* try to open the file                                                */
-    Int file = SyFopen(filename, append ? "a" : "w");
+    Int file = SyFopen(filename, append ? "a" : "w", TRUE);
     if ( file == -1 )
         return 0;
 

src/saveload.c

@@ -58,12 +58,11 @@ static Int OpenForSave( Obj fname )
       Pr("Already saving\n", 0, 0);
       return 1;
     }
-  SaveFile = SyFopen(CONST_CSTR_STRING(fname), "wb");
-  if (SaveFile == -1)
-    {
-      Pr("Couldn't open file %s to save workspace\n",
-         (UInt)CONST_CSTR_STRING(fname), 0);
-      return 1;
+    SaveFile = SyFopen(CONST_CSTR_STRING(fname), "wb", TRUE);
+    if (SaveFile == -1) {
+        Pr("Couldn't open file %s to save workspace\n",
+           (UInt)CONST_CSTR_STRING(fname), 0);
+        return 1;
     }
   LBPointer = LoadBuffer;
   LBEnd = LBPointer+sizeof(LoadBuffer);
@@ -89,11 +88,10 @@ static void OpenForLoad( const Char *fname )
     {
       Panic("Internal error -- this should never happen");
     }
-  LoadFile = SyFopen(fname, "rb");
-  if (LoadFile == -1)
-    {
-      Pr("Couldn't open saved workspace %s\n",(Int)fname, 0);
-      SyExit(1);
+    LoadFile = SyFopen(fname, "rb", TRUE);
+    if (LoadFile == -1) {
+        Pr("Couldn't open saved workspace %s\n", (Int)fname, 0);
+        SyExit(1);
     }
 }
 

src/streams.c

@@ -1264,8 +1264,8 @@ static Obj FuncINPUT_TEXT_FILE(Obj self, Obj filename)
 
     /* call the system dependent function                                  */
     SyClearErrorNo();
-    fid = SyFopen( CONST_CSTR_STRING(filename), "r" );
-    if ( fid == - 1)
+    fid = SyFopen(CONST_CSTR_STRING(filename), "r", TRUE);
+    if (fid == -1)
         SySetErrorNo();
     return fid == -1 ? Fail : INTOBJ_INT(fid);
 }
@@ -1286,24 +1286,26 @@ static Obj FuncIS_END_OF_FILE(Obj self, Obj fid)
 
 /****************************************************************************
 **
-*F  FuncOUTPUT_TEXT_FILE( <self>, <name>, <append> )  . . . . . open a stream
+*F  FuncOUTPUT_TEXT_FILE( <self>, <name>, <append>, <comp> )  . open a stream
 */
-static Obj FuncOUTPUT_TEXT_FILE(Obj self, Obj filename, Obj append)
+static Obj FuncOUTPUT_TEXT_FILE(Obj self, Obj filename, Obj append, Obj comp)
 {
     Int             fid;
 
     RequireStringRep(SELF_NAME, filename);
     RequireTrueOrFalse(SELF_NAME, append);
+    RequireTrueOrFalse(SELF_NAME, comp);
 
+    Int compbool = (comp == True);
     /* call the system dependent function                                  */
     SyClearErrorNo();
     if ( append == True ) {
-        fid = SyFopen( CONST_CSTR_STRING(filename), "a" );
+        fid = SyFopen(CONST_CSTR_STRING(filename), "a", compbool);
     }
     else {
-        fid = SyFopen( CONST_CSTR_STRING(filename), "w" );
+        fid = SyFopen(CONST_CSTR_STRING(filename), "w", compbool);
     }
-    if ( fid == - 1)
+    if (fid == -1)
         SySetErrorNo();
     return fid == -1 ? Fail : INTOBJ_INT(fid);
 }
@@ -1773,7 +1775,7 @@ static StructGVarFunc GVarFuncs[] = {
     GVAR_FUNC_1ARGS(LIST_DIR, dirname),
     GVAR_FUNC_1ARGS(CLOSE_FILE, fid),
     GVAR_FUNC_1ARGS(INPUT_TEXT_FILE, filename),
-    GVAR_FUNC_2ARGS(OUTPUT_TEXT_FILE, filename, append),
+    GVAR_FUNC_3ARGS(OUTPUT_TEXT_FILE, filename, append, compress),
     GVAR_FUNC_1ARGS(IS_END_OF_FILE, fid),
     GVAR_FUNC_1ARGS(POSITION_FILE, fid),
     GVAR_FUNC_1ARGS(READ_BYTE_FILE, fid),

src/sysfiles.c

@@ -237,7 +237,7 @@ Int4 SyGAPCRC( const Char * name )
     Int         seen_nl;
 
     /* the CRC of a non existing file is 0                                 */
-    fid = SyFopen( name, "r" );
+    fid = SyFopen(name, "r", TRUE);
     if ( fid == -1 ) {
         return 0;
     }
@@ -585,7 +585,7 @@ void SyBufSetEOF(Int fid)
 
 /****************************************************************************
 **
-*F  SyFopen( <name>, <mode> ) . . . . . . . .  open the file with name <name>
+*F  SyFopen( <name>, <mode>, <transcompress> ) open the file with name <name>
 **
 **  The function 'SyFopen'  is called to open the file with the name  <name>.
 **  If <mode> is "r" it is opened for reading, in this case  it  must  exist.
@@ -606,11 +606,12 @@ void SyBufSetEOF(Int fid)
 **
 **  Right now GAP does not read nonascii files, but if this changes sometimes
 **  'SyFopen' must adjust the mode argument to open the file in binary mode.
+**
+**  If <transcompress> is TRUE, files with names ending '.gz' will be
+**  automatically compressed/decompressed using gzip.
 */
 
-Int SyFopen (
-    const Char *        name,
-    const Char *        mode )
+Int SyFopen(const Char * name, const Char * mode, BOOL transcompress)
 {
     Int                 fid;
     Char                namegz [1024];
@@ -666,16 +667,18 @@ Int SyFopen (
 #endif
 
     /* try to open the file                                                */
-    if (endsgz && (syBuf[fid].gzfp = gzopen(name, mode))) {
+    if (endsgz && transcompress && (syBuf[fid].gzfp = gzopen(name, mode))) {
         syBuf[fid].type = gzip_socket;
         syBuf[fid].fp = -1;
         syBuf[fid].bufno = -1;
-    } else if (0 <= (syBuf[fid].fp = open(name, flags, 0644))) {
+    }
+    else if (0 <= (syBuf[fid].fp = open(name, flags, 0644))) {
         syBuf[fid].type = raw_socket;
         syBuf[fid].echo = syBuf[fid].fp;
         syBuf[fid].bufno = -1;
     }
-    else if (strncmp(mode, "r", 1) == 0 && SyIsReadableFile(namegz) == 0 &&
+    else if (strncmp(mode, "r", 1) == 0 && transcompress &&
+             SyIsReadableFile(namegz) == 0 &&
              (syBuf[fid].gzfp = gzopen(namegz, mode))) {
         syBuf[fid].type = gzip_socket;
         syBuf[fid].fp = -1;

src/sysfiles.h

@@ -94,7 +94,7 @@ void SyBufSetEOF(Int fid);
 
 /****************************************************************************
 **
-*F  SyFopen( <name>, <mode> ) . . . . . . . .  open the file with name <name>
+*F  SyFopen( <name>, <mode>, <transcompress> ) open the file with name <name>
 **
 **  The function 'SyFopen'  is called to open the file with the name  <name>.
 **  If <mode> is "r" it is opened for reading, in this case  it  must  exist.
@@ -113,8 +113,11 @@ void SyBufSetEOF(Int fid);
 **  If it is necessary to adjust the  filename  this  should  be  done  here.
 **  Right now GAP does not read nonascii files, but if this changes sometimes
 **  'SyFopen' must adjust the mode argument to open the file in binary mode.
+**
+**  If <transcompress> is TRUE, files with names ending '.gz' will be
+**  automatically compressed/decompressed using gzip.
 */
-Int SyFopen(const Char * name, const Char * mode);
+Int SyFopen(const Char * name, const Char * mode, BOOL transcompress);
 
 
 /****************************************************************************

tst/testinstall/compressed.tst

@@ -1,30 +1,49 @@
-#@local dir,fname,isGzippedFile,stream,str
+#@local o,dir,fname,rawfname,isGzippedFile,stream,str
 gap> START_TEST("compressed.tst");
 gap> dir := DirectoryTemporary();;
 gap> fname := Filename(dir, "test.g.gz");;
+gap> rawfname := Filename(dir, "rawtest.g.gz");;
 
 # Let us check when we have written a compressed file by checking the gzip header
-gap> isGzippedFile := function(dir, name)
->    local out, str,prog;
->    str := "";
->    out := OutputTextString(str, true);
->    Process(dir, Filename(DirectoriesSystemPrograms(),"cat"), InputTextNone(), out, [name]);
->    return str{[1..2]} = "\037\213";
+# We need raw file access to do this, so we use 'IO'. We stub out this part of the
+# test if IO is not loaded
+gap> isGzippedFile := function(fname)
+>    local ins, str;
+>    if not IsPackageLoaded("IO") then return true; fi;
+>    # Use 'ValueGlobal' to avoid warnings about undefined functions
+>    ins := ValueGlobal("IO_File")(fname, "r");
+>    str := ValueGlobal("IO_Read")(ins, 2);;
+>    # All gzipped files should start with these two characters
+>    return str = [CharInt(31),CharInt(139)];
 >  end;;
 gap> str := "hello\ngoodbye\n";;
 
-# Write a compressed file
-gap> FileString( fname, str ) = Length(str);
+# Write an uncompressed file
+gap> FileString( rawfname, str ) = Length(str);
 true
 
+# Write a compressed file, using OutputGzipFile
+gap> o := OutputGzipFile(fname, false);;
+gap> WriteAll(o, str);
+true
+gap> CloseStream(o);
+
 # Check file really is compressed
-gap> isGzippedFile(dir, "test.g.gz");
+gap> isGzippedFile(fname);
 true
 
+# Check file really is NOT compressed
+gap> isGzippedFile(rawfname);
+false
+
 # Check reading compressed file
 gap> StringFile( fname ) = str;
 true
 
+# Check reading uncompressed file
+gap> StringFile( rawfname ) = str;
+true
+
 # Check gz is added transparently
 gap> StringFile( Filename(dir, "test.g") ) = str;
 true
@@ -68,7 +87,7 @@ true
 gap> CloseStream(stream);
 
 # Test multiple writes
-gap> stream := OutputTextFile( fname, false );;
+gap> stream := OutputGzipFile( fname, false );;
 gap> PrintTo( stream, "1");
 gap> AppendTo( stream, "2");
 gap> PrintTo( stream, "3");
@@ -77,7 +96,7 @@ true
 gap> CloseStream(stream);
 gap> stream;
 closed-stream
-gap> isGzippedFile(dir, "test.g.gz");
+gap> isGzippedFile(fname);
 true
 
 # verify it
@@ -113,7 +132,7 @@ gap> stream;
 closed-stream
 
 # append to initial data
-gap> stream := OutputTextFile( fname, true );;
+gap> stream := OutputGzipFile( fname, true );;
 gap> PrintTo( stream, "4");
 gap> CloseStream(stream);
 
@@ -126,7 +145,7 @@ gap> stream;
 closed-stream
 
 # overwrite initial data
-gap> stream := OutputTextFile( fname, false );;
+gap> stream := OutputGzipFile( fname, false );;
 gap> PrintTo( stream, "new content");
 gap> CloseStream(stream);
 
@@ -145,15 +164,15 @@ gap> ReadAll(stream, 3);
 gap> CloseStream(stream);
 
 # test PrintFormattingStatus
-gap> stream := OutputTextFile( fname, false );;
+gap> stream := OutputGzipFile( fname, false );;
 gap> PrintFormattingStatus(stream);
 true
 gap> PrintTo( stream, "a very long line that GAP is going to wrap at 80 chars by default if we don't do anything about it\n");
 gap> CloseStream(stream);
 gap> StringFile(fname);
 "a very long line that GAP is going to wrap at 80 chars by default if we don't\
  \\\ndo anything about it\n"
-gap> stream := OutputTextFile( fname, false );;
+gap> stream := OutputGzipFile( fname, false );;
 gap> SetPrintFormattingStatus(stream, false);
 gap> PrintFormattingStatus(stream);
 false