From 838eb1fa2d365ee085082b26e8b8b6ec657af572 Mon Sep 17 00:00:00 2001
From: Paul Sokolovsky <pfalcon@users.sourceforge.net>
Date: Mon, 17 Nov 2014 00:16:14 +0200
Subject: [PATCH] stream: Implement seek operation support via ioctl, wrapped
in generic method.
Also, implement for unix port.
---
py/obj.h | 13 +++++++++++--
py/qstrdefs.h | 1 +
py/stream.c | 26 ++++++++++++++++++++++++++
py/stream.h | 1 +
unix/file.c | 19 +++++++++++++++++++
unix/mpconfigport.h | 7 +++++++
6 files changed, 65 insertions(+), 2 deletions(-)
diff --git a/py/obj.h b/py/obj.h
index ab5123417..09f277a19 100644
--- a/py/obj.h
+++ b/py/obj.h
@@ -231,8 +231,6 @@ void mp_get_buffer_raise(mp_obj_t obj, mp_buffer_info_t *bufinfo, mp_uint_t flag
// Stream protocol
#define MP_STREAM_ERROR (-1)
-#define MP_STREAM_FLUSH (1)
-#define MP_STREAM_POLL (2)
typedef struct _mp_stream_p_t {
// On error, functions should return MP_STREAM_ERROR and fill in *errcode (values
// are implementation-dependent, but will be exposed to user, e.g. via exception).
@@ -242,6 +240,17 @@ typedef struct _mp_stream_p_t {
mp_uint_t is_text : 1; // default is bytes, set this for text stream
} mp_stream_p_t;
+// Stream ioctl request codes
+#define MP_STREAM_FLUSH (1)
+#define MP_STREAM_SEEK (2)
+#define MP_STREAM_POLL (3)
+
+// Argument structure for MP_STREAM_SEEK
+struct mp_stream_seek_t {
+ mp_off_t offset;
+ int whence;
+};
+
struct _mp_obj_type_t {
mp_obj_base_t base;
qstr name;
diff --git a/py/qstrdefs.h b/py/qstrdefs.h
index 1506d0a26..7f1b3c417 100644
--- a/py/qstrdefs.h
+++ b/py/qstrdefs.h
@@ -455,6 +455,7 @@ Q(readall)
Q(readinto)
Q(readline)
Q(readlines)
+Q(seek)
Q(FileIO)
Q(TextIOWrapper)
Q(StringIO)
diff --git a/py/stream.c b/py/stream.c
index a8561dbbc..1361d6c72 100644
--- a/py/stream.c
+++ b/py/stream.c
@@ -380,6 +380,32 @@ mp_obj_t mp_stream_unbuffered_iter(mp_obj_t self) {
return MP_OBJ_STOP_ITERATION;
}
+STATIC mp_obj_t stream_seek(mp_uint_t n_args, const mp_obj_t *args) {
+ struct _mp_obj_base_t *o = (struct _mp_obj_base_t *)args[0];
+ if (o->type->stream_p == NULL || o->type->stream_p->read == NULL) {
+ // CPython: io.UnsupportedOperation, OSError subclass
+ nlr_raise(mp_obj_new_exception_msg(&mp_type_OSError, "Operation not supported"));
+ }
+
+ struct mp_stream_seek_t seek_s;
+ // TODO: Could be uint64
+ seek_s.offset = mp_obj_get_int(args[1]);
+ seek_s.whence = 0;
+ if (n_args == 3) {
+ seek_s.whence = mp_obj_get_int(args[2]);
+ }
+
+ int error;
+ mp_uint_t res = o->type->stream_p->ioctl(o, MP_STREAM_SEEK, (mp_uint_t)&seek_s, &error);
+ if (res == MP_STREAM_ERROR) {
+ nlr_raise(mp_obj_new_exception_arg1(&mp_type_OSError, MP_OBJ_NEW_SMALL_INT(error)));
+ }
+
+ // TODO: Could be uint64
+ return mp_obj_new_int_from_uint(seek_s.offset);
+}
+MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mp_stream_seek_obj, 2, 3, stream_seek);
+
MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mp_stream_read_obj, 1, 2, stream_read);
MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mp_stream_readinto_obj, 2, 3, stream_readinto);
MP_DEFINE_CONST_FUN_OBJ_1(mp_stream_readall_obj, stream_readall);
diff --git a/py/stream.h b/py/stream.h
index 733c48e33..df7168535 100644
--- a/py/stream.h
+++ b/py/stream.h
@@ -30,6 +30,7 @@ MP_DECLARE_CONST_FUN_OBJ(mp_stream_readall_obj);
MP_DECLARE_CONST_FUN_OBJ(mp_stream_unbuffered_readline_obj);
MP_DECLARE_CONST_FUN_OBJ(mp_stream_unbuffered_readlines_obj);
MP_DECLARE_CONST_FUN_OBJ(mp_stream_write_obj);
+MP_DECLARE_CONST_FUN_OBJ(mp_stream_seek_obj);
// Iterator which uses mp_stream_unbuffered_readline_obj
mp_obj_t mp_stream_unbuffered_iter(mp_obj_t self);
diff --git a/unix/file.c b/unix/file.c
index 21b272684..b2746e078 100644
--- a/unix/file.c
+++ b/unix/file.c
@@ -88,6 +88,23 @@ STATIC mp_uint_t fdfile_write(mp_obj_t o_in, const void *buf, mp_uint_t size, in
return r;
}
+STATIC mp_uint_t fdfile_ioctl(mp_obj_t o_in, mp_uint_t request, mp_uint_t arg, int *errcode) {
+ mp_obj_fdfile_t *o = o_in;
+ if (request == MP_STREAM_SEEK) {
+ struct mp_stream_seek_t *s = (struct mp_stream_seek_t*)arg;
+ off_t off = lseek(o->fd, s->offset, s->whence);
+ if (off == (off_t)-1) {
+ *errcode = errno;
+ return MP_STREAM_ERROR;
+ }
+ s->offset = off;
+ return 0;
+ } else {
+ *errcode = EINVAL;
+ return MP_STREAM_ERROR;
+ }
+}
+
STATIC mp_obj_t fdfile_flush(mp_obj_t self_in) {
mp_obj_fdfile_t *self = self_in;
check_fd_is_open(self);
@@ -192,6 +209,7 @@ STATIC const mp_map_elem_t rawfile_locals_dict_table[] = {
{ MP_OBJ_NEW_QSTR(MP_QSTR_readline), (mp_obj_t)&mp_stream_unbuffered_readline_obj},
{ MP_OBJ_NEW_QSTR(MP_QSTR_readlines), (mp_obj_t)&mp_stream_unbuffered_readlines_obj},
{ MP_OBJ_NEW_QSTR(MP_QSTR_write), (mp_obj_t)&mp_stream_write_obj },
+ { MP_OBJ_NEW_QSTR(MP_QSTR_seek), (mp_obj_t)&mp_stream_seek_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_flush), (mp_obj_t)&fdfile_flush_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_close), (mp_obj_t)&fdfile_close_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR___enter__), (mp_obj_t)&mp_identity_obj },
@@ -204,6 +222,7 @@ STATIC MP_DEFINE_CONST_DICT(rawfile_locals_dict, rawfile_locals_dict_table);
STATIC const mp_stream_p_t fileio_stream_p = {
.read = fdfile_read,
.write = fdfile_write,
+ .ioctl = fdfile_ioctl,
};
const mp_obj_type_t mp_type_fileio = {
diff --git a/unix/mpconfigport.h b/unix/mpconfigport.h
index 7844cc937..1baf56a11 100644
--- a/unix/mpconfigport.h
+++ b/unix/mpconfigport.h
@@ -122,6 +122,13 @@ typedef unsigned int mp_uint_t; // must be pointer size
#define BYTES_PER_WORD sizeof(mp_int_t)
+// Cannot include <sys/types.h>, as it may lead to symbol name clashes
+#if _FILE_OFFSET_BITS == 64 && !defined(__LP64__)
+typedef long long mp_off_t;
+#else
+typedef long mp_off_t;
+#endif
+
typedef void *machine_ptr_t; // must be of pointer size
typedef const void *machine_const_ptr_t; // must be of pointer size
--
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