Jim F's brainchild
diff --git a/Modules/cStringIO.c b/Modules/cStringIO.c
new file mode 100644
index 0000000..e9f8033
--- /dev/null
+++ b/Modules/cStringIO.c
@@ -0,0 +1,678 @@
+/*
+
+  $Id$
+
+  A simple fast partial StringIO replacement.
+
+
+
+     Copyright 
+
+       Copyright 1996 Digital Creations, L.C., 910 Princess Anne
+       Street, Suite 300, Fredericksburg, Virginia 22401 U.S.A. All
+       rights reserved.  Copyright in this software is owned by DCLC,
+       unless otherwise indicated. Permission to use, copy and
+       distribute this software is hereby granted, provided that the
+       above copyright notice appear in all copies and that both that
+       copyright notice and this permission notice appear. Note that
+       any product, process or technology described in this software
+       may be the subject of other Intellectual Property rights
+       reserved by Digital Creations, L.C. and are not licensed
+       hereunder.
+
+     Trademarks 
+
+       Digital Creations & DCLC, are trademarks of Digital Creations, L.C..
+       All other trademarks are owned by their respective companies. 
+
+     No Warranty 
+
+       The software is provided "as is" without warranty of any kind,
+       either express or implied, including, but not limited to, the
+       implied warranties of merchantability, fitness for a particular
+       purpose, or non-infringement. This software could include
+       technical inaccuracies or typographical errors. Changes are
+       periodically made to the software; these changes will be
+       incorporated in new editions of the software. DCLC may make
+       improvements and/or changes in this software at any time
+       without notice.
+
+     Limitation Of Liability 
+
+       In no event will DCLC be liable for direct, indirect, special,
+       incidental, economic, cover, or consequential damages arising
+       out of the use of or inability to use this software even if
+       advised of the possibility of such damages. Some states do not
+       allow the exclusion or limitation of implied warranties or
+       limitation of liability for incidental or consequential
+       damages, so the above limitation or exclusion may not apply to
+       you.
+
+    If you have questions regarding this software,
+    contact:
+   
+      Jim Fulton, jim@digicool.com
+      Digital Creations L.C.  
+   
+      (540) 371-6909
+
+
+  $Log$
+  Revision 2.1  1996/12/05 23:30:40  guido
+  Jim F's brainchild
+
+  Revision 1.6  1996/10/15 18:42:07  jim
+  Added lots of casts to make warnings go away.
+
+  Revision 1.5  1996/10/11 21:03:42  jim
+  *** empty log message ***
+
+  Revision 1.4  1996/10/11 21:02:15  jim
+  *** empty log message ***
+
+  Revision 1.3  1996/10/07 20:51:38  chris
+  *** empty log message ***
+
+  Revision 1.2  1996/07/18 13:08:34  jfulton
+  *** empty log message ***
+
+  Revision 1.1  1996/07/15 17:06:33  jfulton
+  Initial version.
+
+
+*/
+static char cStringIO_module_documentation[] = 
+"A simple fast partial StringIO replacement.\n"
+"\n"
+"This module provides a simple useful replacement for\n"
+"the StringIO module that is written in C.  It does not provide the\n"
+"full generality if StringIO, but it provides anough for most\n"
+"applications and is especially useful in conjuction with the\n"
+"pickle module.\n"
+"\n"
+"Usage:\n"
+"\n"
+"  from cStringIO import StringIO\n"
+"\n"
+"  an_output_stream=StringIO()\n"
+"  an_output_stream.write(some_stuff)\n"
+"  ...\n"
+"  value=an_output_stream.getvalue() # str(an_output_stream) works too!\n"
+"\n"
+"  an_input_stream=StringIO(a_string)\n"
+"  spam=an_input_stream.readline()\n"
+"  spam=an_input_stream.read(5)\n"
+"  an_input_stream.reset()           # OK, start over, note no seek yet\n"
+"  spam=an_input_stream.read()       # and read it all\n"
+"  \n"
+"If someone else wants to provide a more complete implementation,\n"
+"go for it. :-)  \n"
+;
+
+#include "Python.h"
+#include "import.h"
+
+static PyObject *ErrorObject;
+
+#define ASSIGN(V,E) {PyObject *__e; __e=(E); Py_XDECREF(V); (V)=__e;}
+#define UNLESS(E) if(!(E))
+#define UNLESS_ASSIGN(V,E) ASSIGN(V,E) UNLESS(V)
+#define Py_ASSIGN(P,E) if(!PyObject_AssignExpression(&(P),(E))) return NULL
+
+/* ----------------------------------------------------- */
+
+/* Declarations for objects of type StringO */
+
+typedef struct {
+  PyObject_HEAD
+  char *buf;
+  int pos, string_size, buf_size, closed;
+} Oobject;
+
+staticforward PyTypeObject Otype;
+
+/* ---------------------------------------------------------------- */
+
+/* Declarations for objects of type StringI */
+
+typedef struct {
+  PyObject_HEAD
+  char *buf;
+  int pos, string_size, closed;
+  PyObject *pbuf;
+} Iobject;
+
+staticforward PyTypeObject Itype;
+
+
+
+/* ---------------------------------------------------------------- */
+
+static char O_reset__doc__[] = 
+"reset() -- Reset the file position to the beginning"
+;
+
+static PyObject *
+O_reset(Oobject *self, PyObject *args)
+{
+  self->pos = 0;
+
+  Py_INCREF(Py_None);
+  return Py_None;
+}
+
+
+static char O_tell__doc__[] =
+"tell() -- get the current position.";
+
+static PyObject *
+O_tell(Oobject *self, PyObject *args)
+{
+  return PyInt_FromLong(self->pos);
+}
+
+
+static char O_seek__doc__[] =
+"seek(position)       -- set the current position\n"
+"seek(position, mode) -- mode 0: absolute; 1: relative; 2: relative to EOF";
+
+static PyObject *
+O_seek(Oobject *self, PyObject *args)
+{
+  int position, mode = 0;
+
+  UNLESS(PyArg_ParseTuple(args, "i|i", &position, &mode))
+  {
+    return NULL;
+  }
+
+  if (mode == 2)
+  {
+    position += self->string_size;
+  }
+  else if (mode == 1)
+  {
+    position += self->pos;
+  }
+
+  self->pos = (position > self->string_size ? self->string_size : 
+	       (position < 0 ? 0 : position));
+
+  return PyInt_FromLong(self->pos);
+}
+
+static char O_read__doc__[] = 
+"read([s]) -- Read s characters, or the rest of the string"
+;
+
+static int
+O_cread(Oobject *self, char **output, int n)
+{
+  int l;
+
+  l = self->string_size - self->pos;  
+  if (n < 0 || n > l)
+  {
+    n = l;
+  }
+
+  *output=self->buf + self->pos;
+  self->pos += n;
+  return n;
+}
+
+static PyObject *
+O_read(Oobject *self, PyObject *args)
+{
+  int n = -1;
+  char *output;
+
+  UNLESS(PyArg_ParseTuple(args, "|i", &n)) return NULL;
+
+  n=O_cread(self,&output,n);
+
+  return PyString_FromStringAndSize(output, n);
+}
+
+
+static char O_readline__doc__[] = 
+"readline() -- Read one line"
+;
+
+static int
+O_creadline(Oobject *self, char **output)
+{
+  char *n, *s;
+  int l;
+
+  for (n = self->buf + self->pos, s = self->buf + self->string_size; 
+       n < s && *n != '\n'; n++);
+  if (n < s) n++;
+ 
+  *output=self->buf + self->pos;
+  l = n - self->buf - self->pos;
+  self->pos += l;
+  return l;
+}
+
+static PyObject *
+O_readline(Oobject *self, PyObject *args)
+{
+  int n;
+  char *output;
+
+  n=O_creadline(self,&output);
+  return PyString_FromStringAndSize(output, n);
+}
+
+static char O_write__doc__[] = 
+"write(s) -- Write a string to the file"
+"\n\nNote (hack:) writing None resets the buffer"
+;
+
+
+static int
+O_cwrite(Oobject *self, char *c, int l)
+{
+  int newl;
+  newl=self->pos+l;
+  if(newl > self->buf_size)
+    {
+      self->buf_size*=2;
+      if(self->buf_size < newl) self->buf_size=newl;
+      UNLESS(self->buf=(char*)realloc(self->buf, self->buf_size*sizeof(char)))
+	{
+	  PyErr_SetString(PyExc_MemoryError,"out of memory");
+	  self->buf_size=self->pos=0;
+	  return -1;
+	}
+    }
+
+  memcpy(self->buf+self->pos,c,l);
+
+  self->pos += l;
+
+  if (self->string_size < self->pos)
+    {
+      self->string_size = self->pos;
+    }
+
+  return l;
+}
+
+static PyObject *
+O_write(Oobject *self, PyObject *args)
+{
+  PyObject *s;
+  char *c;
+  int l;
+
+  UNLESS(PyArg_Parse(args, "O", &s)) return NULL;
+  if(s!=Py_None)
+    {
+      UNLESS(-1 != (l=PyString_Size(s))) return NULL;
+      UNLESS(c=PyString_AsString(s)) return NULL;
+      UNLESS(-1 != O_cwrite(self,c,l)) return NULL;
+    }
+  else
+    {
+      self->pos=0;
+      self->string_size = 0;
+    }
+
+  Py_INCREF(self);
+  return (PyObject *)self;
+}
+
+static PyObject *
+O_repr(self)
+	Oobject *self;
+{
+  return PyString_FromStringAndSize(self->buf,self->string_size);
+}
+
+static PyObject *
+O_getval(self,args)
+	Oobject *self;
+	PyObject *args;
+{
+  return PyString_FromStringAndSize(self->buf,self->pos);
+}
+
+static char O_truncate__doc__[] = 
+"truncate(): truncate the file at the current position.";
+
+static PyObject *
+O_truncate(self, args)
+           Oobject *self;
+           PyObject *args;
+{
+  self->string_size = self->pos;
+  Py_INCREF(Py_None);
+  return Py_None;
+}
+
+static char O_isatty__doc__[] = "isatty(): always returns 0";
+
+static PyObject *
+O_isatty(self, args)
+           Oobject *self;
+           PyObject *args;
+{
+  return PyInt_FromLong(0);
+}
+
+static char O_close__doc__[] = "close(): explicitly release resources held.";
+
+static PyObject *
+O_close(self, args)
+        Oobject *self;
+        PyObject *args;
+{
+  free(self->buf);
+
+  self->pos = self->string_size = self->buf_size = 0;
+  self->closed = 1;
+
+  Py_INCREF(Py_None);
+  return Py_None;
+}
+
+static char O_flush__doc__[] = "flush(): does nothing.";
+
+static PyObject *
+O_flush(self, args)
+        Oobject *self;
+        PyObject *args;
+{
+  Py_INCREF(Py_None);
+  return Py_None;
+}
+
+
+static char O_writelines__doc__[] = "blah";
+static PyObject *
+O_writelines(self, args)
+             Oobject *self;
+             PyObject *args;
+{
+  PyObject *string_module = 0;
+  static PyObject *string_joinfields = 0;
+
+  UNLESS(PyArg_Parse(args, "O", args))
+  {
+    return NULL;
+  }
+
+  if (!string_joinfields)
+  {
+    UNLESS(string_module = PyImport_ImportModule("string"))
+    {
+      return NULL;
+    }
+
+    UNLESS(string_joinfields=
+        PyObject_GetAttrString(string_module, "joinfields"))
+    {
+      return NULL;
+    }
+
+    Py_DECREF(string_module);
+  }
+
+  if (PyObject_Length(args) == -1)
+  {
+    return NULL;
+  }
+
+  return O_write(self, 
+      PyObject_CallFunction(string_joinfields, "Os", args, ""));
+}
+
+static struct PyMethodDef O_methods[] = {
+  {"read",       (PyCFunction)O_read,         1,      O_read__doc__},
+  {"readline",   (PyCFunction)O_readline,     0,      O_readline__doc__},
+  {"write",	 (PyCFunction)O_write,        0,      O_write__doc__},
+  {"reset",      (PyCFunction)O_reset,        0,      O_reset__doc__},
+  {"seek",       (PyCFunction)O_seek,         1,      O_seek__doc__},
+  {"tell",       (PyCFunction)O_tell,         0,      O_tell__doc__},
+  {"getvalue",   (PyCFunction)O_getval,       0,      "getvalue() -- Get the string value"},
+  {"truncate",   (PyCFunction)O_truncate,     0,      O_truncate__doc__},
+  {"isatty",     (PyCFunction)O_isatty,       0,      O_isatty__doc__},
+  {"close",      (PyCFunction)O_close,        0,      O_close__doc__},
+  {"flush",      (PyCFunction)O_flush,        0,      O_flush__doc__},
+  {"writelines", (PyCFunction)O_writelines,   0,      O_writelines__doc__},
+  {NULL,		NULL}		/* sentinel */
+};
+
+/* ---------- */
+
+
+static Oobject *
+newOobject(int size)
+{
+  Oobject *self;
+	
+  self = PyObject_NEW(Oobject, &Otype);
+  if (self == NULL)
+    return NULL;
+  self->pos=0;
+  self->closed = 0;
+  self->string_size = 0;
+
+  UNLESS(self->buf=malloc(size*sizeof(char)))
+    {
+      PyErr_SetString(PyExc_MemoryError,"out of memory");
+      self->buf_size = 0;
+      return NULL;
+    }
+
+  self->buf_size=size;
+  return self;
+}
+
+
+static void
+O_dealloc(self)
+	Oobject *self;
+{
+  free(self->buf);
+  PyMem_DEL(self);
+}
+
+static PyObject *
+O_getattr(self, name)
+	Oobject *self;
+	char *name;
+{
+  return Py_FindMethod(O_methods, (PyObject *)self, name);
+}
+
+static char Otype__doc__[] = 
+"Simple type for output to strings."
+;
+
+static PyTypeObject Otype = {
+	PyObject_HEAD_INIT(&PyType_Type)
+	0,				/*ob_size*/
+	"StringO",			/*tp_name*/
+	sizeof(Oobject),		/*tp_basicsize*/
+	0,				/*tp_itemsize*/
+	/* methods */
+	(destructor)O_dealloc,	/*tp_dealloc*/
+	(printfunc)0,		/*tp_print*/
+	(getattrfunc)O_getattr,	/*tp_getattr*/
+	(setattrfunc)0,	/*tp_setattr*/
+	(cmpfunc)0,		/*tp_compare*/
+	(reprfunc)O_repr,		/*tp_repr*/
+	0,			/*tp_as_number*/
+	0,		/*tp_as_sequence*/
+	0,		/*tp_as_mapping*/
+	(hashfunc)0,		/*tp_hash*/
+	(ternaryfunc)0,		/*tp_call*/
+	(reprfunc)0,		/*tp_str*/
+
+	/* Space for future expansion */
+	0L,0L,0L,0L,
+	Otype__doc__ /* Documentation string */
+};
+
+/* End of code for StringO objects */
+/* -------------------------------------------------------- */
+
+static PyObject *
+I_close(self, args)
+        Iobject *self;
+        PyObject *args;
+{
+  Py_DECREF(self->pbuf);
+
+  self->pos = self->string_size = 0;
+  self->closed = 1;
+
+  Py_INCREF(Py_None);
+  return Py_None;
+}
+
+static struct PyMethodDef I_methods[] = {
+  {"read",	(PyCFunction)O_read,         1,      O_read__doc__},
+  {"readline",	(PyCFunction)O_readline,	0,	O_readline__doc__},
+  {"reset",	(PyCFunction)O_reset,	0,	O_reset__doc__},
+  {"seek",      (PyCFunction)O_seek,         1,      O_seek__doc__},  
+  {"tell",      (PyCFunction)O_tell,         0,      O_tell__doc__},
+  {"truncate",  (PyCFunction)O_truncate,     0,      O_truncate__doc__},
+  {"isatty",    (PyCFunction)O_isatty,       0,      O_isatty__doc__},
+  {"close",     (PyCFunction)I_close,        0,      O_close__doc__},
+  {"flush",     (PyCFunction)O_flush,        0,      O_flush__doc__},
+  {NULL,		NULL}		/* sentinel */
+};
+
+/* ---------- */
+
+
+static Iobject *
+newIobject(PyObject *s)
+{
+  Iobject *self;
+  char *buf;
+  int size;
+	
+  UNLESS(buf=PyString_AsString(s)) return NULL;
+  UNLESS(-1 != (size=PyString_Size(s))) return NULL;
+  UNLESS(self = PyObject_NEW(Iobject, &Itype)) return NULL;
+  Py_INCREF(s);
+  self->buf=buf;
+  self->string_size=size;
+  self->pbuf=s;
+  self->pos=0;
+  self->closed = 0;
+  
+  return self;
+}
+
+
+static void
+I_dealloc(self)
+	Iobject *self;
+{
+  Py_DECREF(self->pbuf);
+  PyMem_DEL(self);
+}
+
+static PyObject *
+I_getattr(self, name)
+	Iobject *self;
+	char *name;
+{
+  return Py_FindMethod(I_methods, (PyObject *)self, name);
+}
+
+static char Itype__doc__[] = 
+"Simple type for treating strings as input file streams"
+;
+
+static PyTypeObject Itype = {
+	PyObject_HEAD_INIT(&PyType_Type)
+	0,				/*ob_size*/
+	"StringI",			/*tp_name*/
+	sizeof(Iobject),		/*tp_basicsize*/
+	0,				/*tp_itemsize*/
+	/* methods */
+	(destructor)I_dealloc,	/*tp_dealloc*/
+	(printfunc)0,		/*tp_print*/
+	(getattrfunc)I_getattr,	/*tp_getattr*/
+	(setattrfunc)0,	/*tp_setattr*/
+	(cmpfunc)0,		/*tp_compare*/
+	(reprfunc)0,		/*tp_repr*/
+	0,			/*tp_as_number*/
+	0,		/*tp_as_sequence*/
+	0,		/*tp_as_mapping*/
+	(hashfunc)0,		/*tp_hash*/
+	(ternaryfunc)0,		/*tp_call*/
+	(reprfunc)0,		/*tp_str*/
+
+	/* Space for future expansion */
+	0L,0L,0L,0L,
+	Itype__doc__ /* Documentation string */
+};
+
+/* End of code for StringI objects */
+/* -------------------------------------------------------- */
+
+
+static char IO_StringIO__doc__[] =
+"StringIO([s]) -- Return a StringIO-like stream for reading or writing"
+;
+
+static PyObject *
+IO_StringIO(self, args)
+	PyObject *self;	/* Not used */
+	PyObject *args;
+{
+  PyObject *s=0;
+
+  UNLESS(PyArg_ParseTuple(args, "|O", &s)) return NULL;
+  if(s) return (PyObject *)newIobject(s);
+  return (PyObject *)newOobject(128);
+}
+
+/* List of methods defined in the module */
+
+static struct PyMethodDef IO_methods[] = {
+	{"StringIO",	(PyCFunction)IO_StringIO,	1,	IO_StringIO__doc__},
+	{NULL,		NULL}		/* sentinel */
+};
+
+
+/* Initialization function for the module (*must* be called initcStringIO) */
+
+void
+initcStringIO()
+{
+  PyObject *m, *d;
+
+  /* Create the module and add the functions */
+  m = Py_InitModule4("cStringIO", IO_methods,
+		     cStringIO_module_documentation,
+		     (PyObject*)NULL,PYTHON_API_VERSION);
+
+  /* Add some symbolic constants to the module */
+  d = PyModule_GetDict(m);
+  ErrorObject = PyString_FromString("cStringIO.error");
+  PyDict_SetItemString(d, "error", ErrorObject);
+  
+  PyDict_SetItemString(d,"cread", PyCObject_FromVoidPtr(O_cread,NULL));
+  PyDict_SetItemString(d,"creadline", PyCObject_FromVoidPtr(O_creadline,NULL));
+  PyDict_SetItemString(d,"cwrite", PyCObject_FromVoidPtr(O_cwrite,NULL));
+  PyDict_SetItemString(d,"cgetvalue", PyCObject_FromVoidPtr(O_getval,NULL));
+  PyDict_SetItemString(d,"NewInput", PyCObject_FromVoidPtr(newIobject,NULL));
+  PyDict_SetItemString(d,"NewOutput", PyCObject_FromVoidPtr(newOobject,NULL));
+  
+  PyDict_SetItemString(d,"InputType",  (PyObject*)&Itype);
+  PyDict_SetItemString(d,"OutputType", (PyObject*)&Otype);
+  
+
+  /* Check for errors */
+  if (PyErr_Occurred())
+    Py_FatalError("can't initialize module cStringIO");
+}