# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1481237456 -3600
# Node ID 2ba43e72f7f427d41e72fa5521171bcc1d5136b1
# Parent  c2bdc5b1a125b68ce87a5d3eae8ff56943d66e08
Added support for closing files and streams.
Made the low-level write operation return the number of bytes written, also
declaring the IOError that can be raised.

diff -r c2bdc5b1a125 -r 2ba43e72f7f4 lib/__builtins__/file.py
--- a/lib/__builtins__/file.py	Thu Dec 08 23:36:43 2016 +0100
+++ b/lib/__builtins__/file.py	Thu Dec 08 23:50:56 2016 +0100
@@ -69,7 +69,11 @@
         check_string(s)
         native._fwrite(self.__data__, s)
 
-    def close(self): pass
+    def close(self):
+
+        "Close the stream."
+
+        native._fclose(self.__data__)
 
 class file(filestream):
 
diff -r c2bdc5b1a125 -r 2ba43e72f7f4 lib/native.py
--- a/lib/native.py	Thu Dec 08 23:36:43 2016 +0100
+++ b/lib/native.py	Thu Dec 08 23:50:56 2016 +0100
@@ -100,16 +100,18 @@
 
 # Input/output.
 
+def _fclose(fp): IOError
 def _fopen(filename, mode): IOError
 def _fdopen(fd, mode): IOError
+def _close(fd): IOError
 def _read(fd, n): IOError
-def _write(fd, str): pass
+def _write(fd, str): IOError
 
-def _fread(fd, n):
+def _fread(fp, n):
     IOError
     EOFError
 
-def _fwrite(fd, str):
+def _fwrite(fp, str):
     IOError
     EOFError
 
diff -r c2bdc5b1a125 -r 2ba43e72f7f4 lib/posix/io.py
--- a/lib/posix/io.py	Thu Dec 08 23:36:43 2016 +0100
+++ b/lib/posix/io.py	Thu Dec 08 23:50:56 2016 +0100
@@ -47,7 +47,13 @@
         "Write string 's' to the file."
 
         check_string(s)
-        write(self.fd, s)
+        return write(self.fd, s)
+
+    def close(self):
+
+        "Close the file."
+
+        close(self.fd)
 
 class sysstream(filestream):
 
@@ -68,7 +74,12 @@
 
 # Input/output functions.
 
-def close(fd): pass
+def close(fd):
+
+    "Close the file descriptor 'fd'."
+
+    native._close(fd)
+
 def closerange(fd_low, fd_high): pass
 def dup(fd): pass
 def dup2(old_fd, new_fd): pass
@@ -127,7 +138,7 @@
 
     check_int(fd)
     check_string(s)
-    native._write(fd, s)
+    return native._write(fd, s)
 
 # Constants.
 
diff -r c2bdc5b1a125 -r 2ba43e72f7f4 templates/native.c
--- a/templates/native.c	Thu Dec 08 23:36:43 2016 +0100
+++ b/templates/native.c	Thu Dec 08 23:50:56 2016 +0100
@@ -680,6 +680,19 @@
 
 /* Input/output. */
 
+__attr __fn_native__fclose(__attr __args[])
+{
+    __attr * const fp = &__args[1];
+    /* fp interpreted as FILE reference */
+    FILE *f = (FILE *) fp->datavalue;
+
+    errno = 0;
+    if (fclose(f))
+        __raise_io_error(__new_int(errno));
+
+    return __builtins___none_None;
+}
+
 __attr __fn_native__fopen(__attr __args[])
 {
     __attr * const filename = &__args[1];
@@ -791,6 +804,19 @@
     return __builtins___none_None;
 }
 
+__attr __fn_native__close(__attr __args[])
+{
+    __attr * const fd = &__args[1];
+    /* fd.__data__ interpreted as int */
+    int i = __load_via_object(fd->value, __pos___data__).intvalue;
+
+    errno = 0;
+    if (close(i) == -1)
+        __raise_io_error(__new_int(errno));
+
+    return __builtins___none_None;
+}
+
 __attr __fn_native__read(__attr __args[])
 {
     __attr * const fd = &__args[1];
@@ -808,14 +834,12 @@
 
     if (have_read == -1)
         __raise_io_error(__new_int(errno));
-    else
-    {
-        /* Reserve space for a new string. */
+
+    /* Reserve space for a new string. */
 
-        s = __ALLOCATE(have_read + 1, 1);
-        strncpy(s, (char *) buf, have_read); /* does not null terminate but final byte should be zero */
-        return __new_str(s);
-    }
+    s = __ALLOCATE(have_read + 1, 1);
+    strncpy(s, (char *) buf, have_read); /* does not null terminate but final byte should be zero */
+    return __new_str(s);
 }
 
 __attr __fn_native__write(__attr __args[])
@@ -826,9 +850,15 @@
     int i = __load_via_object(fd->value, __pos___data__).intvalue;
     /* str.__data__ interpreted as string */
     char *s = __load_via_object(str->value, __pos___data__).strvalue;
+    ssize_t have_written;
 
-    write(i, s, sizeof(char) * strlen(s));
-    return __builtins___none_None;
+    errno = 0;
+    have_written = write(i, s, sizeof(char) * strlen(s));
+
+    if (have_written == -1)
+        __raise_io_error(__new_int(errno));
+
+    return __new_int(have_written);
 }
 
 /* Module initialisation. */
diff -r c2bdc5b1a125 -r 2ba43e72f7f4 templates/native.h
--- a/templates/native.h	Thu Dec 08 23:36:43 2016 +0100
+++ b/templates/native.h	Thu Dec 08 23:50:56 2016 +0100
@@ -100,10 +100,12 @@
 
 /* Input/output. */
 
+__attr __fn_native__fclose(__attr __args[]);
 __attr __fn_native__fopen(__attr __args[]);
 __attr __fn_native__fdopen(__attr __args[]);
 __attr __fn_native__fread(__attr __args[]);
 __attr __fn_native__fwrite(__attr __args[]);
+__attr __fn_native__close(__attr __args[]);
 __attr __fn_native__read(__attr __args[]);
 __attr __fn_native__write(__attr __args[]);