* algebra/net.spad.pamphlet (Conduit): New.

	(InputByteConduit): Likewise.
	(OutputByteConduit): Likewise.
	(InputOutputByteConduit): Likewise.
	* algebra/exposed.lsp.pamphlet: Expose Conduit, InputByteConduit,
	OutputByteConduit, InputOutputByteConduit.
	* algebra/Makefile.pamphlet (axiom_algebra_layer_0): Include CONDUIT.
	(axiom_algebra_layer_13): Include INBCON, INBCON-, OUTBCON, OUTBCON-.
	(axiom_algebra_layer_14): Include IOBCON.

4 files changed, 115 insertions, 6 deletions

diff --git a/src/algebra/Makefile.in b/src/algebra/Makefile.in
index 1c06da1f..0facef02 100644
--- a/src/algebra/Makefile.in
+++ b/src/algebra/Makefile.in
@@ -363,7 +363,7 @@ axiom_algebra_layer_0 = \
   ABELSG-  ORDSET   ORDSET-  FNCAT    FILECAT  SEXCAT   \
   MKBCFUNC MKRECORD MKUCFUNC DROPT1   PLOT1    ITFUN2   \
   ITFUN3   STREAM1  STREAM2  STREAM3  ANY1     SEGBIND2 \
-  COMBOPC  EQ2      NONE1
+  COMBOPC  EQ2      NONE1    CONDUIT
 
 axiom_algebra_layer_0_nrlibs = \
 	$(addsuffix .NRLIB/code.$(FASLEXT),$(axiom_algebra_layer_0))
@@ -569,7 +569,8 @@ axiom_algebra_layer_13 = \
   ODESYS   ODETOOLS ORDFUNS  PERMAN   \
   PFECAT   PFECAT-  POINT    PSEUDLIN \
   PTPACK   REP2     SETMN    SEX      \
-  SYMFUNC  VECTOR2     CHAR  
+  SYMFUNC  VECTOR2     CHAR  \
+  INBCON   INBCON-  OUTBCON  OUTBCON-
 
 axiom_algebra_layer_13_nrlibs = \
 	$(addsuffix .NRLIB/code.$(FASLEXT),$(axiom_algebra_layer_13))
@@ -636,7 +637,8 @@ axiom_algebra_layer_14 = \
   VOID     WEIER    WP       \
  EQTBL  GSTBL   HASHTBL \
   INTABL  INTFTBL  STBL    STRTBL\
-  TABLE     FST SYMS     SYMTAB
+  TABLE     FST SYMS     SYMTAB \
+  IOBCON
 
 
 axiom_algebra_layer_14_nrlibs = \
diff --git a/src/algebra/Makefile.pamphlet b/src/algebra/Makefile.pamphlet
index 6073630c..170c5cab 100644
--- a/src/algebra/Makefile.pamphlet
+++ b/src/algebra/Makefile.pamphlet
@@ -192,7 +192,7 @@ axiom_algebra_layer_0 = \
   ABELSG-  ORDSET   ORDSET-  FNCAT    FILECAT  SEXCAT   \
   MKBCFUNC MKRECORD MKUCFUNC DROPT1   PLOT1    ITFUN2   \
   ITFUN3   STREAM1  STREAM2  STREAM3  ANY1     SEGBIND2 \
-  COMBOPC  EQ2      NONE1
+  COMBOPC  EQ2      NONE1    CONDUIT
 
 axiom_algebra_layer_0_nrlibs = \
 	$(addsuffix .NRLIB/code.$(FASLEXT),$(axiom_algebra_layer_0))
@@ -595,7 +595,8 @@ axiom_algebra_layer_13 = \
   ODESYS   ODETOOLS ORDFUNS  PERMAN   \
   PFECAT   PFECAT-  POINT    PSEUDLIN \
   PTPACK   REP2     SETMN    SEX      \
-  SYMFUNC  VECTOR2     CHAR  
+  SYMFUNC  VECTOR2     CHAR  \
+  INBCON   INBCON-  OUTBCON  OUTBCON-
 
 axiom_algebra_layer_13_nrlibs = \
 	$(addsuffix .NRLIB/code.$(FASLEXT),$(axiom_algebra_layer_13))
@@ -759,7 +760,8 @@ axiom_algebra_layer_14 = \
   VOID     WEIER    WP       \
  EQTBL  GSTBL   HASHTBL \
   INTABL  INTFTBL  STBL    STRTBL\
-  TABLE     FST SYMS     SYMTAB
+  TABLE     FST SYMS     SYMTAB \
+  IOBCON
 
 
 axiom_algebra_layer_14_nrlibs = \
diff --git a/src/algebra/exposed.lsp.pamphlet b/src/algebra/exposed.lsp.pamphlet
index 4a729c69..a4b5a8c4 100644
--- a/src/algebra/exposed.lsp.pamphlet
+++ b/src/algebra/exposed.lsp.pamphlet
@@ -572,6 +572,7 @@
   (|CombinatorialOpsCategory| . COMBOPC)
   (|CommutativeRing| . COMRING)
   (|ComplexCategory| . COMPCAT)
+  (|Conduit| . CONDUIT)
   (|ConvertibleTo| . KONVERT)
   (|DequeueAggregate| . DQAGG)
   (|Dictionary| . DIAGG)
@@ -627,6 +628,8 @@
   (|IndexedAggregate| . IXAGG)
   (|IndexedDirectProductCategory| . IDPC)
   (|InnerEvalable| . IEVALAB)
+  (|InputByteConduit| . INBCON)
+  (|InputOutputByteConduit| IOBCON)
   (|IntegerNumberSystem| . INS)
   (|IntegralDomain| . INTDOM)
   (|IntervalCategory| . INTCAT)
@@ -670,6 +673,7 @@
   (|OrderedMultisetAggregate| . OMSAGG)
   (|OrderedRing| . ORDRING)
   (|OrderedSet| . ORDSET)
+  (|OutputByteConduit| . OUTBCON)
   (|PAdicIntegerCategory| . PADICCT)
   (|PartialDifferentialRing| . PDRING)
   (|PartialTranscendentalFunctions| . PTRANFN)
diff --git a/src/algebra/net.spad.pamphlet b/src/algebra/net.spad.pamphlet
index 70130a5b..4a8d4961 100644
--- a/src/algebra/net.spad.pamphlet
+++ b/src/algebra/net.spad.pamphlet
@@ -11,6 +11,101 @@
 \tableofcontents
 \eject
 
+\section{The Conduit category}
+
+<<category CONDUIT Conduit>>=
+)abbrev category CONDUIT Conduit
+++ Author: Gabriel Dos Reis
+++ Date Created: August 24, 2008
+++ Date Last Modified: August 24, 2008
+++ Description:
+++   This category is the root of the I/O conduits.
+Conduit(): Category == with
+    close!: % -> %
+      ++ close!(c) closes the conduit c, changing its state to one
+      ++ that is invalid for future read or write operations.
+
+@
+
+\subsection{The InputByteConduit category}
+
+<<category INBCON InputByteConduit>>=
+)abbrev category INBCON InputByteConduit
+++ Author: Gabriel Dos Reis
+++ Date Created: August 24, 2008
+++ Date Last Modified: August 24, 2008
+++ Description:
+++   This category describes input byte stream conduits.
+InputByteConduit(): Category == Conduit with
+    readByteIfCan!: % -> SingleInteger
+      ++ readByteIfCan!(cond) attempts to read a byte from the
+      ++ input conduit `cond'.  Returns the read byte if successful,
+      ++ otherwise return -1.
+      ++ Note: Ideally, the return value should have been of type
+      ++   Maybe Byte; but that would have implied allocating
+      ++   a cons cell for every read attempt, which is overkill.
+    readBytes!: (%,ByteArray) -> SingleInteger
+      ++ readBytes!(c,b) reads byte sequences from conduit `c' into
+      ++ the byte buffer `b'.  The actual number of bytes written
+      ++ is returned.
+  add
+    readBytes!(cond,ary) ==
+      count: SingleInteger := 0
+      b : SingleInteger
+      while count < #ary and ((b := readByteIfCan! cond) >= 0) repeat
+        qsetelt!(ary,count,b : Byte)
+        count := count + 1
+      count
+
+@
+
+\subsection{The OutputByteConduit category}
+
+<<category OUTBCON OutputByteConduit>>=
+)abbrev category OUTBCON OutputByteConduit
+++ Author: Gabriel Dos Reis
+++ Date Created: August 24, 2008
+++ Date Last Modified: August 24, 2008
+++ Description:
+++   This category describes output byte stream conduits.
+OutputByteConduit(): Category == Conduit with
+    writeByteIfCan!: (%,Byte) -> SingleInteger
+      ++ writeByteIfCan!(c,b) attempts to write the byte `b' on
+      ++ the conduit `c'.  Returns the written byte if successful,
+      ++ otherwise, returns -1.
+      ++ Note: Ideally, the return value should have been of type
+      ++   Maybe Byte; but that would have implied allocating
+      ++   a cons cell for every write attempt, which is overkill.
+    writeBytes!: (%,ByteArray) -> SingleInteger
+      ++ writeBytes!(c,b) write bytes from buffer `b' 
+      ++ onto the conduit `c'.  The actual number of written 
+      ++ bytes is returned.
+  add
+    writeBytes!(cond,ary) ==
+      count: SingleInteger := 0
+      while count < #ary and 
+        writeByteIfCan!(cond,qelt(ary,count)) >= 0 repeat
+          count := count + 1
+      count
+
+@
+
+\subsection{The InputOutputByteConduit category}
+
+<<category IOBCON InputOutputByteConduit>>=
+)abbrev category IOBCON InputOutputByteConduit
+++ Author: Gabriel Dos Reis
+++ Date Created: August 24, 2008
+++ Date Last Modified: August 24, 2008
+++ See Also: InputByteConduit, OutputByteConduit.
+++ Description:
+++   This category describes byte stream conduits supporting
+++   both input and output operations.
+InputOutputByteConduit(): Category ==
+    Join(InputByteConduit,OutputByteConduit)
+
+@
+
 \section{The Hostname domain}
 
 <<domain HOSTNAME Hostname>>=
@@ -94,6 +189,12 @@ PortNumber(): Public == Private where
 
 <<*>>=
 <<license>>
+
+<<category CONDUIT Conduit>>
+<<category INBCON InputByteConduit>>
+<<category OUTBCON OutputByteConduit>>
+<<category IOBCON InputOutputByteConduit>>
+
 <<domain HOSTNAME Hostname>>
 <<domain PORTNUM PortNumber>>