# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1483831622 -3600
# Node ID 28e2996df412498f7cb5256a5d10221e51b48649
# Parent  06c4fdc8da56050ebfaeef1d0ad3a746ca77b8e6
Added stream flushing to make raw_input work properly.
Introduced separate readline approaches for streams and files, where streams are
read one byte at a time, whereas files are read in chunks according to the
specified buffer size.

diff -r 06c4fdc8da56 -r 28e2996df412 lib/__builtins__/file.py
--- a/lib/__builtins__/file.py	Sat Jan 07 16:23:25 2017 +0100
+++ b/lib/__builtins__/file.py	Sun Jan 08 00:27:02 2017 +0100
@@ -20,7 +20,7 @@
 """
 
 from __builtins__.types import check_int, check_string
-from native import isinstance as _isinstance, fclose, fopen, fread, fwrite
+from native import isinstance as _isinstance, fclose, fflush, fopen, fread, fwrite
 
 class filestream:
 
@@ -46,6 +46,12 @@
         else:
             return bytes
 
+    def flush(self):
+
+        "Flush the stream."
+
+        fflush(self.__data__)
+
     def read(self, n=0):
 
         "Read 'n' bytes from the stream."
@@ -66,7 +72,7 @@
 
             try:
                 while True:
-                    l.append(fread(self.__data__, self.bufsize))
+                    self._read_data(l)
 
             # Handle end-of-file reads.
 
@@ -97,18 +103,10 @@
             l = []
 
             # Read until end-of-line or end-of-file.
-            # NOTE: Only POSIX newlines are supported currently.
 
             try:
-                while True:
-                    s = fread(self.__data__, 1)
-                    l.append(s)
-
-                    # Where a newline has been read, provide the preceding data
-                    # plus the newline indicator.
-
-                    if s == "\n":
-                        break
+                while not self._read_until_newline(l):
+                    pass
 
             # Handle end-of-file reads.
 
@@ -119,6 +117,22 @@
 
         return self._convert(s)
 
+    def _read_data(self, l):
+
+        "Read data into 'l'."
+
+        l.append(fread(self.__data__, self.bufsize))
+
+    def _read_until_newline(self, l):
+
+        "Read data into 'l', returning whether a newline has been read."
+
+        # NOTE: Only POSIX newlines are supported currently.
+
+        s = fread(self.__data__, 1)
+        l.append(s)
+        return s == "\n"
+
     def readlines(self, n=None): pass
 
     def write(self, s):
@@ -154,5 +168,43 @@
 
         get_using(filestream.__init__, self)(encoding, bufsize)
         self.__data__ = fopen(filename, mode)
+        self.buffered = ""
+
+    def _get_data(self):
+
+        "Get data from the file."
+
+        if self.buffered:
+            s = self.buffered
+            self.buffered = ""
+        else:
+            s = fread(self.__data__, self.bufsize)
+
+        return s
+
+    def _read_data(self, l):
+
+        "Read data into 'l'."
+
+        s = self._get_data()
+        l.append(s)
+
+    def _read_until_newline(self, l):
+
+        "Read data into 'l', returning whether a newline has been read."
+
+        s = self._get_data()
+
+        # NOTE: Only POSIX newlines are supported currently.
+
+        i = s.find("\n")
+
+        if i != -1:
+            l.append(s[:i+1])
+            self.buffered = s[i+1:]
+            return True
+
+        l.append(s)
+        return False
 
 # vim: tabstop=4 expandtab shiftwidth=4
diff -r 06c4fdc8da56 -r 28e2996df412 lib/__builtins__/io.py
--- a/lib/__builtins__/io.py	Sat Jan 07 16:23:25 2017 +0100
+++ b/lib/__builtins__/io.py	Sun Jan 08 00:27:02 2017 +0100
@@ -32,6 +32,7 @@
 
     if prompt:
         stdout.write(prompt)
+        stdout.flush()
 
     return lstdin.readline()
 
diff -r 06c4fdc8da56 -r 28e2996df412 lib/native/__init__.py
--- a/lib/native/__init__.py	Sat Jan 07 16:23:25 2017 +0100
+++ b/lib/native/__init__.py	Sun Jan 08 00:27:02 2017 +0100
@@ -31,7 +31,7 @@
 
 from native.iconv import iconv, iconv_close, iconv_open, iconv_reset
 
-from native.io import fclose, fopen, fdopen, close, read, write, fread, fwrite
+from native.io import fclose, fflush, fopen, fdopen, close, read, write, fread, fwrite
 
 from native.limits import get_maxint, get_minint
 
diff -r 06c4fdc8da56 -r 28e2996df412 lib/native/io.py
--- a/lib/native/io.py	Sat Jan 07 16:23:25 2017 +0100
+++ b/lib/native/io.py	Sun Jan 08 00:27:02 2017 +0100
@@ -25,6 +25,7 @@
 """
 
 def fclose(fp): IOError
+def fflush(fp): IOError
 def fopen(filename, mode): IOError
 def fdopen(fd, mode): IOError
 def close(fd): IOError
diff -r 06c4fdc8da56 -r 28e2996df412 templates/native/io.c
--- a/templates/native/io.c	Sat Jan 07 16:23:25 2017 +0100
+++ b/templates/native/io.c	Sun Jan 08 00:27:02 2017 +0100
@@ -44,6 +44,19 @@
     return __builtins___none_None;
 }
 
+__attr __fn_native_io_fflush(__attr __args[])
+{
+    __attr * const fp = &__args[1];
+    /* fp interpreted as FILE reference */
+    FILE *f = (FILE *) fp->datavalue;
+
+    errno = 0;
+    if (fflush(f))
+        __raise_io_error(__new_int(errno));
+
+    return __builtins___none_None;
+}
+
 __attr __fn_native_io_fopen(__attr __args[])
 {
     __attr * const filename = &__args[1];
diff -r 06c4fdc8da56 -r 28e2996df412 templates/native/io.h
--- a/templates/native/io.h	Sat Jan 07 16:23:25 2017 +0100
+++ b/templates/native/io.h	Sun Jan 08 00:27:02 2017 +0100
@@ -24,6 +24,7 @@
 /* Input/output. */
 
 __attr __fn_native_io_fclose(__attr __args[]);
+__attr __fn_native_io_fflush(__attr __args[]);
 __attr __fn_native_io_fopen(__attr __args[]);
 __attr __fn_native_io_fdopen(__attr __args[]);
 __attr __fn_native_io_fread(__attr __args[]);
diff -r 06c4fdc8da56 -r 28e2996df412 tests/read_file.py
--- a/tests/read_file.py	Sat Jan 07 16:23:25 2017 +0100
+++ b/tests/read_file.py	Sun Jan 08 00:27:02 2017 +0100
@@ -9,6 +9,8 @@
     print s                         # try:
     s = f.read(49)
     print s                         #     f = open("tests/read_file.py")   # this file!
+    s = f.readline()
+    print s                         # except IOError, exc:
     s = f.read()
     print s
 finally: