/* GIO - GLib Input, Output and Streaming Library * * Copyright (C) 2006-2007 Red Hat, Inc. * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General * Public License along with this library; if not, write to the * Free Software Foundation, Inc., 59 Temple Place, Suite 330, * Boston, MA 02111-1307, USA. * * Author: Christian Kellner */ #include #include "gmemoryoutputstream.h" #include "goutputstream.h" #include "gseekable.h" #include "gsimpleasyncresult.h" #include "string.h" #include "glibintl.h" #include "gioalias.h" /** * SECTION:gmemoryoutputstream * @short_description: Streaming output operations on memory chunks * @include: gio.h * @see_also: #GMemoryInputStream * * #GMemoryOutputStream is a class for using arbitrary * memory chunks as output for GIO streaming output operations. * */ #define MIN_ARRAY_SIZE 16 struct _GMemoryOutputStreamPrivate { gpointer data; gsize len; goffset pos; GReallocFunc realloc_fn; GDestroyNotify destroy; }; static void g_memory_output_stream_finalize (GObject *object); static gssize g_memory_output_stream_write (GOutputStream *stream, const void *buffer, gsize count, GCancellable *cancellable, GError **error); static gboolean g_memory_output_stream_close (GOutputStream *stream, GCancellable *cancellable, GError **error); static void g_memory_output_stream_write_async (GOutputStream *stream, const void *buffer, gsize count, int io_priority, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer data); static gssize g_memory_output_stream_write_finish (GOutputStream *stream, GAsyncResult *result, GError **error); static void g_memory_output_stream_close_async (GOutputStream *stream, int io_priority, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer data); static gboolean g_memory_output_stream_close_finish (GOutputStream *stream, GAsyncResult *result, GError **error); static void g_memory_output_stream_seekable_iface_init (GSeekableIface *iface); static goffset g_memory_output_stream_tell (GSeekable *seekable); static gboolean g_memory_output_stream_can_seek (GSeekable *seekable); static gboolean g_memory_output_stream_seek (GSeekable *seekable, goffset offset, GSeekType type, GCancellable *cancellable, GError **error); static gboolean g_memory_output_stream_can_truncate (GSeekable *seekable); static gboolean g_memory_output_stream_truncate (GSeekable *seekable, goffset offset, GCancellable *cancellable, GError **error); G_DEFINE_TYPE_WITH_CODE (GMemoryOutputStream, g_memory_output_stream, G_TYPE_OUTPUT_STREAM, G_IMPLEMENT_INTERFACE (G_TYPE_SEEKABLE, g_memory_output_stream_seekable_iface_init)) static void g_memory_output_stream_class_init (GMemoryOutputStreamClass *klass) { GOutputStreamClass *ostream_class; GObjectClass *gobject_class; g_type_class_add_private (klass, sizeof (GMemoryOutputStreamPrivate)); gobject_class = G_OBJECT_CLASS (klass); gobject_class->finalize = g_memory_output_stream_finalize; ostream_class = G_OUTPUT_STREAM_CLASS (klass); ostream_class->write_fn = g_memory_output_stream_write; ostream_class->close_fn = g_memory_output_stream_close; ostream_class->write_async = g_memory_output_stream_write_async; ostream_class->write_finish = g_memory_output_stream_write_finish; ostream_class->close_async = g_memory_output_stream_close_async; ostream_class->close_finish = g_memory_output_stream_close_finish; } static void g_memory_output_stream_finalize (GObject *object) { GMemoryOutputStream *stream; GMemoryOutputStreamPrivate *priv; stream = G_MEMORY_OUTPUT_STREAM (object); priv = stream->priv; if (priv->destroy) priv->destroy (priv->data); if (G_OBJECT_CLASS (g_memory_output_stream_parent_class)->finalize) (*G_OBJECT_CLASS (g_memory_output_stream_parent_class)->finalize) (object); } static void g_memory_output_stream_seekable_iface_init (GSeekableIface *iface) { iface->tell = g_memory_output_stream_tell; iface->can_seek = g_memory_output_stream_can_seek; iface->seek = g_memory_output_stream_seek; iface->can_truncate = g_memory_output_stream_can_truncate; iface->truncate_fn = g_memory_output_stream_truncate; } static void g_memory_output_stream_init (GMemoryOutputStream *stream) { stream->priv = G_TYPE_INSTANCE_GET_PRIVATE (stream, G_TYPE_MEMORY_OUTPUT_STREAM, GMemoryOutputStreamPrivate); } /** * g_memory_output_stream_new: * @data: pointer to a chunk of memory to use, or %NULL * @len: the size of @data * @realloc_fn: a function with realloc() semantics to be called when * @data needs to be grown, or %NULL * @destroy: a function to be called on @data when the stream is finalized, * or %NULL * * Creates a new #GMemoryOutputStream. * * If @data is non-%NULL, the stream will use that for its internal storage. * If @realloc_fn is non-%NULL, it will be used for resizing the internal * storage when necessary. To construct a fixed-size output stream, * pass %NULL as @realloc_fn. * |[ * /* a stream that can grow */ * stream = g_memory_output_stream_new (NULL, 0, realloc, free); * * /* a fixed-size stream */ * data = malloc (200); * stream2 = g_memory_output_stream_new (data, 200, NULL, free); * ]| * * Return value: A newly created #GMemoryOutputStream object. **/ GOutputStream * g_memory_output_stream_new (gpointer data, gsize len, GReallocFunc realloc_fn, GDestroyNotify destroy) { GOutputStream *stream; GMemoryOutputStreamPrivate *priv; stream = g_object_new (G_TYPE_MEMORY_OUTPUT_STREAM, NULL); priv = G_MEMORY_OUTPUT_STREAM (stream)->priv; priv->data = data; priv->len = len; priv->realloc_fn = realloc_fn; priv->destroy = destroy; priv->pos = 0; return stream; } /** * g_memory_output_stream_get_data: * @ostream: a #GMemoryOutputStream * * Gets any loaded data from the @ostream. * * Note that the returned pointer may become invalid on the next * write or truncate operation on the stream. * * Returns: pointer to the stream's data **/ gpointer g_memory_output_stream_get_data (GMemoryOutputStream *ostream) { g_return_val_if_fail (G_IS_MEMORY_OUTPUT_STREAM (ostream), NULL); return ostream->priv->data; } /** * g_memory_output_stream_get_size: * @ostream: a #GMemoryOutputStream * * Gets the size of the loaded data from the @ostream. * * Note that the returned size may become invalid on the next * write or truncate operation on the stream. * * Returns: the size of the stream's data */ gsize g_memory_output_stream_get_size (GMemoryOutputStream *ostream) { g_return_val_if_fail (G_IS_MEMORY_OUTPUT_STREAM (ostream), 0); return ostream->priv->len; } static gboolean array_check_boundary (GMemoryOutputStream *stream, goffset size, GError **error) { if (size > G_MAXUINT) { g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED, _("Reached maximum data array limit")); return FALSE; } return TRUE; } static gboolean array_resize (GMemoryOutputStream *ostream, gsize size, gboolean allow_partial, GError **error) { GMemoryOutputStreamPrivate *priv; gpointer data; gsize len; priv = ostream->priv; if (!array_check_boundary (ostream, size, error)) return FALSE; if (priv->len == size) return TRUE; if (!priv->realloc_fn) { if (allow_partial && priv->pos < priv->len) return TRUE; /* Short write */ g_set_error (error, G_IO_ERROR, G_IO_ERROR_NO_SPACE, _("Memory output stream not resizable")); return FALSE; } len = priv->len; data = priv->realloc_fn (priv->data, size); if (!data) { if (allow_partial && priv->pos < priv->len) return TRUE; /* Short write */ g_set_error (error, G_IO_ERROR, G_IO_ERROR_NO_SPACE, _("Failed to resize memory output stream")); return FALSE; } if (size > len) memset ((guint8 *)data + len, 0, size - len); priv->data = data; priv->len = size; return TRUE; } static gint g_nearest_pow (gint num) { gint n = 1; while (n < num) n <<= 1; return n; } static gssize g_memory_output_stream_write (GOutputStream *stream, const void *buffer, gsize count, GCancellable *cancellable, GError **error) { GMemoryOutputStream *ostream; GMemoryOutputStreamPrivate *priv; guint8 *dest; gsize new_size; ostream = G_MEMORY_OUTPUT_STREAM (stream); priv = ostream->priv; if (count == 0) return 0; if (priv->pos + count > priv->len) { /* At least enought to fit the write, rounded up for greater than linear growth */ new_size = g_nearest_pow (priv->pos + count); new_size = MAX (new_size, MIN_ARRAY_SIZE); if (!array_resize (ostream, new_size, TRUE, error)) return -1; } /* Make sure we handle short writes if the array_resize only added part of the required memory */ count = MIN (count, priv->len - priv->pos); dest = (guint8 *)priv->data + priv->pos; memcpy (dest, buffer, count); priv->pos += count; return count; } static gboolean g_memory_output_stream_close (GOutputStream *stream, GCancellable *cancellable, GError **error) { return TRUE; } static void g_memory_output_stream_write_async (GOutputStream *stream, const void *buffer, gsize count, int io_priority, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer data) { GSimpleAsyncResult *simple; gssize nwritten; nwritten = g_memory_output_stream_write (stream, buffer, count, cancellable, NULL); simple = g_simple_async_result_new (G_OBJECT (stream), callback, data, g_memory_output_stream_write_async); g_simple_async_result_set_op_res_gssize (simple, nwritten); g_simple_async_result_complete_in_idle (simple); g_object_unref (simple); } static gssize g_memory_output_stream_write_finish (GOutputStream *stream, GAsyncResult *result, GError **error) { GSimpleAsyncResult *simple; gssize nwritten; simple = G_SIMPLE_ASYNC_RESULT (result); g_warn_if_fail (g_simple_async_result_get_source_tag (simple) == g_memory_output_stream_write_async); nwritten = g_simple_async_result_get_op_res_gssize (simple); return nwritten; } static void g_memory_output_stream_close_async (GOutputStream *stream, int io_priority, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer data) { GSimpleAsyncResult *simple; simple = g_simple_async_result_new (G_OBJECT (stream), callback, data, g_memory_output_stream_close_async); /* will always return TRUE */ g_memory_output_stream_close (stream, cancellable, NULL); g_simple_async_result_complete_in_idle (simple); g_object_unref (simple); } static gboolean g_memory_output_stream_close_finish (GOutputStream *stream, GAsyncResult *result, GError **error) { GSimpleAsyncResult *simple; simple = G_SIMPLE_ASYNC_RESULT (result); g_warn_if_fail (g_simple_async_result_get_source_tag (simple) == g_memory_output_stream_close_async); return TRUE; } static goffset g_memory_output_stream_tell (GSeekable *seekable) { GMemoryOutputStream *stream; GMemoryOutputStreamPrivate *priv; stream = G_MEMORY_OUTPUT_STREAM (seekable); priv = stream->priv; return priv->pos; } static gboolean g_memory_output_stream_can_seek (GSeekable *seekable) { return TRUE; } static gboolean g_memory_output_stream_seek (GSeekable *seekable, goffset offset, GSeekType type, GCancellable *cancellable, GError **error) { GMemoryOutputStream *stream; GMemoryOutputStreamPrivate *priv; goffset absolute; stream = G_MEMORY_OUTPUT_STREAM (seekable); priv = stream->priv; switch (type) { case G_SEEK_CUR: absolute = priv->pos + offset; break; case G_SEEK_SET: absolute = offset; break; case G_SEEK_END: absolute = priv->len + offset; break; default: g_set_error (error, G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT, _("Invalid GSeekType supplied")); return FALSE; } if (absolute < 0) { g_set_error (error, G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT, _("Invalid seek request")); return FALSE; } if (!array_check_boundary (stream, absolute, error)) return FALSE; priv->pos = absolute; return TRUE; } static gboolean g_memory_output_stream_can_truncate (GSeekable *seekable) { GMemoryOutputStream *ostream; GMemoryOutputStreamPrivate *priv; ostream = G_MEMORY_OUTPUT_STREAM (seekable); priv = ostream->priv; return priv->realloc_fn != NULL; } static gboolean g_memory_output_stream_truncate (GSeekable *seekable, goffset offset, GCancellable *cancellable, GError **error) { GMemoryOutputStream *ostream; GMemoryOutputStreamPrivate *priv; ostream = G_MEMORY_OUTPUT_STREAM (seekable); priv = ostream->priv; if (!array_resize (ostream, offset, FALSE, error)) return FALSE; return TRUE; } #define __G_MEMORY_OUTPUT_STREAM_C__ #include "gioaliasdef.c"