From 432dcb583312f5e90ecfff7a2e72db8da3b5ee50 Mon Sep 17 00:00:00 2001
From: wmayer <wmayer@users.sourceforge.net>
Date: Sat, 11 Jun 2016 11:54:01 +0200
Subject: [PATCH] + extend PyStreambuf to write data

---
 src/Base/Stream.cpp | 143 ++++++++++++++++++++++++++++----------------
 src/Base/Stream.h   |   5 +-
 2 files changed, 97 insertions(+), 51 deletions(-)

diff --git a/src/Base/Stream.cpp b/src/Base/Stream.cpp
index 2b9ce95e4..86c17ca11 100644
--- a/src/Base/Stream.cpp
+++ b/src/Base/Stream.cpp
@@ -523,56 +523,99 @@ IODeviceIStreambuf::seekpos(std::streambuf::pos_type pos,
 }
 
 // ---------------------------------------------------------
-
-PyStreambuf::PyStreambuf(PyObject* o) : inp(o)
-{
-    setg (buffer+pbSize,
-          buffer+pbSize,
-          buffer+pbSize);
-}
-
-int PyStreambuf::underflow()
-{
-    if (gptr() < egptr()) {
-        return *gptr();
-    }
-
-    int numPutback;
-    numPutback = gptr() - eback();
-    if (numPutback > pbSize) {
-        numPutback = pbSize;
-    }
-
-    memcpy (buffer+(pbSize-numPutback), gptr()-numPutback, numPutback);
-
-    int num=0;
-    for (int i=0; i<bufSize; i++) {
-        char c;
-        Py::Tuple arg(1);
-        arg.setItem(0, Py::Int(1));
-        Py::Callable meth(Py::Object(inp).getAttr("read"));
-        try {
-            Py::Char res(meth.apply(arg));
-            c = static_cast<std::string>(res)[0];
-            num++;
-            buffer[pbSize+i] = c;
-            if (c == '\n')
-                break;
-        }
-        catch (Py::Exception& e) {
-            e.clear();
-            if (num == 0)
-                return EOF;
-            break;
-        }
-    }
-
-    setg (buffer+(pbSize-numPutback),
-          buffer+pbSize,
-          buffer+pbSize+num);
-
-    return *gptr();
-}
+
+PyStreambuf::PyStreambuf(PyObject* o) : inp(o)
+{
+    Py_INCREF(inp);
+    setg (buffer+pbSize,
+          buffer+pbSize,
+          buffer+pbSize);
+}
+
+PyStreambuf::~PyStreambuf()
+{
+    Py_DECREF(inp);
+}
+
+std::streambuf::int_type PyStreambuf::underflow()
+{
+    if (gptr() < egptr()) {
+        return *gptr();
+    }
+
+    int numPutback;
+    numPutback = gptr() - eback();
+    if (numPutback > pbSize) {
+        numPutback = pbSize;
+    }
+
+    memcpy (buffer+(pbSize-numPutback), gptr()-numPutback, numPutback);
+
+    int num=0;
+    for (int i=0; i<bufSize; i++) {
+        char c;
+        Py::Tuple arg(1);
+        arg.setItem(0, Py::Int(1));
+        Py::Callable meth(Py::Object(inp).getAttr("read"));
+        try {
+            Py::Char res(meth.apply(arg));
+            c = static_cast<std::string>(res)[0];
+            num++;
+            buffer[pbSize+i] = c;
+            if (c == '\n')
+                break;
+        }
+        catch (Py::Exception& e) {
+            e.clear();
+            if (num == 0)
+                return EOF;
+            break;
+        }
+    }
+
+    setg (buffer+(pbSize-numPutback),
+          buffer+pbSize,
+          buffer+pbSize+num);
+
+    return *gptr();
+}
+
+std::streambuf::int_type
+PyStreambuf::overflow(std::streambuf::int_type c)
+{
+    if (c != EOF) {
+        char z = c;
+
+        try {
+            Py::Tuple arg(1);
+            arg.setItem(0, Py::Char(z));
+            Py::Callable meth(Py::Object(inp).getAttr("write"));
+            meth.apply(arg);
+        }
+        catch(Py::Exception& e) {
+            e.clear();
+            return EOF;
+        }
+    }
+
+    return c;
+}
+
+std::streamsize PyStreambuf::xsputn (const char* s, std::streamsize num)
+{
+    try {
+        Py::Tuple arg(1);
+        arg.setItem(0, Py::String(s, num));
+        Py::Callable meth(Py::Object(inp).getAttr("write"));
+        meth.apply(arg);
+    }
+    catch(Py::Exception& e) {
+        e.clear();
+        return 0;
+    }
+
+    return num;
+}
 
 // ---------------------------------------------------------
 
diff --git a/src/Base/Stream.h b/src/Base/Stream.h
index 26bb4738c..1b8c3d388 100644
--- a/src/Base/Stream.h
+++ b/src/Base/Stream.h
@@ -242,9 +242,12 @@ class BaseExport PyStreambuf : public std::streambuf
 {
 public:
     PyStreambuf(PyObject* o);
+    virtual ~PyStreambuf();
 
 protected:
-    int underflow();
+    int_type underflow();
+    int_type overflow(int_type c = EOF);
+    std::streamsize xsputn (const char* s, std::streamsize num);
 
 private:
     static const int pbSize = 4;