/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- * vi:set noexpandtab tabstop=8 shiftwidth=8: * * Copyright (C) 2021, 2022 Endless OS Foundation LLC * * Author: Philip Withnall * * SPDX-License-Identifier: GPL-2.0+ */ /** * SECTION:gs-download-utils * @short_description: Download and HTTP utilities * * A set of utilities for downloading things and doing HTTP requests. * * Since: 42 */ #include "config.h" #include #include #include #include #include #include "gs-download-utils.h" #include "gs-utils.h" G_DEFINE_QUARK (gs-download-error-quark, gs_download_error) /** * gs_build_soup_session: * * Build a new #SoupSession configured with the gnome-software user agent. * * A new #SoupSession should be used for each independent download context, such * as in different plugins. Each #SoupSession caches HTTP connections and * authentication information, and these likely needn’t be shared between * plugins. Using separate sessions reduces thread contention. * * Returns: (transfer full): a new #SoupSession * Since: 42 */ SoupSession * gs_build_soup_session (void) { return soup_session_new_with_options ("user-agent", gs_user_agent (), "timeout", 10, NULL); } /* See https://httpwg.org/specs/rfc7231.html#http.date * For example: Sun, 06 Nov 1994 08:49:37 GMT */ static gchar * date_time_to_rfc7231 (GDateTime *date_time) { #if SOUP_CHECK_VERSION(3, 0, 0) return soup_date_time_to_string (date_time, SOUP_DATE_HTTP); #else const gchar *day_names[] = { "Mon", "Tue", "Wed", "Thu", "Fri", "Sat", "Sun" }; const gchar *month_names[] = { "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" }; /* We can’t just use g_date_time_format() here because its output * (particularly day and month names) is locale-dependent. * #SoupDate is also a pain to use because there’s no easy way to * convert from a #GDateTime with libsoup-2.4, while preserving the timezone. */ g_autofree gchar *time_str = g_date_time_format (date_time, "%H:%M:%S %Z"); return g_strdup_printf ("%s, %02d %s %d %s", day_names[g_date_time_get_day_of_week (date_time) - 1], g_date_time_get_day_of_month (date_time), month_names[g_date_time_get_month (date_time) - 1], g_date_time_get_year (date_time), time_str); #endif } static GDateTime * date_time_from_rfc7231 (const gchar *rfc7231_str) { #if SOUP_CHECK_VERSION(3, 0, 0) return soup_date_time_new_from_http_string (rfc7231_str); #else g_autoptr(SoupDate) soup_date = NULL; g_autoptr(GTimeZone) tz = NULL; soup_date = soup_date_new_from_string (rfc7231_str); if (soup_date == NULL) return NULL; if (soup_date->utc) tz = g_time_zone_new_utc (); else tz = g_time_zone_new_offset (soup_date->offset * 60); return g_date_time_new (tz, soup_date->year, soup_date->month, soup_date->day, soup_date->hour, soup_date->minute, soup_date->second); #endif } typedef struct { /* Input data. */ gchar *uri; /* (not nullable) (owned) */ GInputStream *input_stream; /* (nullable) (owned) */ GOutputStream *output_stream; /* (nullable) (owned) */ gsize buffer_size_bytes; gchar *last_etag; /* (nullable) (owned) */ GDateTime *last_modified_date; /* (nullable) (owned) */ int io_priority; GsDownloadProgressCallback progress_callback; /* (nullable) */ gpointer progress_user_data; /* In-progress state. */ SoupMessage *message; /* (nullable) (owned) */ gboolean close_input_stream; gboolean close_output_stream; gboolean discard_output_stream; gsize total_read_bytes; gsize total_written_bytes; gsize expected_stream_size_bytes; GBytes *currently_unwritten_chunk; /* (nullable) (owned) */ /* Output data. */ gchar *new_etag; /* (nullable) (owned) */ GDateTime *new_last_modified_date; /* (nullable) (owned) */ GError *error; /* (nullable) (owned) */ } DownloadData; static void download_data_free (DownloadData *data) { g_assert (data->input_stream == NULL || g_input_stream_is_closed (data->input_stream)); g_assert (data->output_stream == NULL || g_output_stream_is_closed (data->output_stream)); g_assert (data->currently_unwritten_chunk == NULL || data->error != NULL); g_clear_object (&data->input_stream); g_clear_object (&data->output_stream); g_clear_pointer (&data->last_etag, g_free); g_clear_pointer (&data->last_modified_date, g_date_time_unref); g_clear_object (&data->message); g_clear_pointer (&data->uri, g_free); g_clear_pointer (&data->new_etag, g_free); g_clear_pointer (&data->new_last_modified_date, g_date_time_unref); g_clear_pointer (&data->currently_unwritten_chunk, g_bytes_unref); g_clear_error (&data->error); g_free (data); } G_DEFINE_AUTOPTR_CLEANUP_FUNC (DownloadData, download_data_free) static void open_input_stream_cb (GObject *source_object, GAsyncResult *result, gpointer user_data); static void read_bytes_cb (GObject *source_object, GAsyncResult *result, gpointer user_data); static void write_bytes_cb (GObject *source_object, GAsyncResult *result, gpointer user_data); static void finish_download (GTask *task, GError *error); static void close_stream_cb (GObject *source_object, GAsyncResult *result, gpointer user_data); static void download_progress (GTask *task); /** * gs_download_stream_async: * @soup_session: a #SoupSession * @uri: (not nullable): the URI to download * @output_stream: (not nullable): an output stream to write the download to * @last_etag: (nullable): the last-known ETag of the URI, or %NULL if unknown * @last_modified_date: (nullable): the last-known Last-Modified date of the * URI, or %NULL if unknown * @io_priority: I/O priority to download and write at * @progress_callback: (nullable): callback to call with progress information * @progress_user_data: (nullable) (closure progress_callback): data to pass * to @progress_callback * @cancellable: (nullable): a #GCancellable, or %NULL * @callback: callback to call once the operation is complete * @user_data: (closure callback): data to pass to @callback * * Download @uri and write it to @output_stream asynchronously. * * If @last_etag is non-%NULL or @last_modified_date is non-%NULL, they will be * sent to the server, which may return a ‘not modified’ response. If so, * @output_stream will not be written to, and will be closed with a cancelled * close operation. This will ensure that the existing content of the output * stream (if it’s a file, for example) will not be overwritten. * * Note that @last_etag must be the ETag value returned by the server last time * the file was downloaded, not the local file ETag generated by GLib. * * If specified, @progress_callback will be called zero or more times until * @callback is called, providing progress updates on the download. * * Since: 43 */ void gs_download_stream_async (SoupSession *soup_session, const gchar *uri, GOutputStream *output_stream, const gchar *last_etag, GDateTime *last_modified_date, int io_priority, GsDownloadProgressCallback progress_callback, gpointer progress_user_data, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer user_data) { g_autoptr(GTask) task = NULL; g_autoptr(GError) local_error = NULL; g_autoptr(SoupMessage) msg = NULL; DownloadData *data; g_autoptr(DownloadData) data_owned = NULL; g_return_if_fail (SOUP_IS_SESSION (soup_session)); g_return_if_fail (uri != NULL); g_return_if_fail (G_IS_OUTPUT_STREAM (output_stream)); g_return_if_fail (cancellable == NULL || G_IS_CANCELLABLE (cancellable)); task = g_task_new (soup_session, cancellable, callback, user_data); g_task_set_source_tag (task, gs_download_stream_async); data = data_owned = g_new0 (DownloadData, 1); data->uri = g_strdup (uri); data->output_stream = g_object_ref (output_stream); data->close_output_stream = TRUE; data->buffer_size_bytes = 8192; /* arbitrarily chosen */ data->io_priority = io_priority; data->progress_callback = progress_callback; data->progress_user_data = progress_user_data; g_task_set_task_data (task, g_steal_pointer (&data_owned), (GDestroyNotify) download_data_free); /* local */ if (g_str_has_prefix (uri, "file://")) { g_autoptr(GFile) local_file = g_file_new_for_path (uri + strlen ("file://")); g_file_read_async (local_file, io_priority, cancellable, open_input_stream_cb, g_steal_pointer (&task)); return; } /* remote */ g_debug ("Downloading %s to %s", uri, G_OBJECT_TYPE_NAME (output_stream)); msg = soup_message_new (SOUP_METHOD_GET, uri); if (msg == NULL) { finish_download (task, g_error_new (G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT, "Failed to parse URI ‘%s’", uri)); return; } data->message = g_object_ref (msg); /* Caching support. Prefer ETags to modification dates, as the latter * have problems with rapid updates and clock drift. */ if (last_etag != NULL && *last_etag == '\0') last_etag = NULL; data->last_etag = g_strdup (last_etag); if (last_modified_date != NULL) data->last_modified_date = g_date_time_ref (last_modified_date); if (last_etag != NULL) { #if SOUP_CHECK_VERSION(3, 0, 0) soup_message_headers_append (soup_message_get_request_headers (msg), "If-None-Match", last_etag); #else soup_message_headers_append (msg->request_headers, "If-None-Match", last_etag); #endif } else if (last_modified_date != NULL) { g_autofree gchar *last_modified_date_str = date_time_to_rfc7231 (last_modified_date); #if SOUP_CHECK_VERSION(3, 0, 0) soup_message_headers_append (soup_message_get_request_headers (msg), "If-Modified-Since", last_modified_date_str); #else soup_message_headers_append (msg->request_headers, "If-Modified-Since", last_modified_date_str); #endif } #if SOUP_CHECK_VERSION(3, 0, 0) soup_session_send_async (soup_session, msg, data->io_priority, cancellable, open_input_stream_cb, g_steal_pointer (&task)); #else soup_session_send_async (soup_session, msg, cancellable, open_input_stream_cb, g_steal_pointer (&task)); #endif } static void open_input_stream_cb (GObject *source_object, GAsyncResult *result, gpointer user_data) { g_autoptr(GTask) task = g_steal_pointer (&user_data); DownloadData *data = g_task_get_task_data (task); GCancellable *cancellable = g_task_get_cancellable (task); g_autoptr(GInputStream) input_stream = NULL; g_autoptr(GError) local_error = NULL; /* This function can be called as a result of either reading a local * file, or sending an HTTP request, so @source_object’s type can vary. */ if (G_IS_FILE (source_object)) { GFile *local_file = G_FILE (source_object); /* Local file. */ input_stream = G_INPUT_STREAM (g_file_read_finish (local_file, result, &local_error)); if (input_stream == NULL) { g_prefix_error (&local_error, "Failed to read ‘%s’: ", g_file_peek_path (local_file)); finish_download (task, g_steal_pointer (&local_error)); return; } g_assert (data->input_stream == NULL); data->input_stream = g_object_ref (input_stream); data->close_input_stream = TRUE; } else if (SOUP_IS_SESSION (source_object)) { SoupSession *soup_session = SOUP_SESSION (source_object); guint status_code; const gchar *new_etag, *new_last_modified_str; /* HTTP request. */ #if SOUP_CHECK_VERSION(3, 0, 0) input_stream = soup_session_send_finish (soup_session, result, &local_error); status_code = soup_message_get_status (data->message); #else input_stream = soup_session_send_finish (soup_session, result, &local_error); status_code = data->message->status_code; #endif if (input_stream != NULL) { g_assert (data->input_stream == NULL); data->input_stream = g_object_ref (input_stream); data->close_input_stream = TRUE; } if (status_code == SOUP_STATUS_NOT_MODIFIED) { /* If the file has not been modified from the ETag or * Last-Modified date we have, finish the download * early. Ensure to close the output stream so that its * existing content is *not* overwritten. * * Preserve the existing ETag. */ data->discard_output_stream = TRUE; data->new_etag = g_strdup (data->last_etag); data->new_last_modified_date = (data->last_modified_date != NULL) ? g_date_time_ref (data->last_modified_date) : NULL; finish_download (task, g_error_new (GS_DOWNLOAD_ERROR, GS_DOWNLOAD_ERROR_NOT_MODIFIED, "Skipped downloading ‘%s’: %s", data->uri, soup_status_get_phrase (status_code))); return; } else if (status_code != SOUP_STATUS_OK) { g_autoptr(GString) str = g_string_new (NULL); g_string_append (str, soup_status_get_phrase (status_code)); if (local_error != NULL) { g_string_append (str, ": "); g_string_append (str, local_error->message); } finish_download (task, g_error_new (G_IO_ERROR, G_IO_ERROR_FAILED, "Failed to download ‘%s’: %s", data->uri, str->str)); return; } g_assert (input_stream != NULL); /* Get the expected download size. */ #if SOUP_CHECK_VERSION(3, 0, 0) data->expected_stream_size_bytes = soup_message_headers_get_content_length (soup_message_get_response_headers (data->message)); #else data->expected_stream_size_bytes = soup_message_headers_get_content_length (data->message->response_headers); #endif /* Store the new ETag for later use. */ #if SOUP_CHECK_VERSION(3, 0, 0) new_etag = soup_message_headers_get_one (soup_message_get_response_headers (data->message), "ETag"); #else new_etag = soup_message_headers_get_one (data->message->response_headers, "ETag"); #endif if (new_etag != NULL && *new_etag == '\0') new_etag = NULL; data->new_etag = g_strdup (new_etag); /* Store the Last-Modified date for later use. */ #if SOUP_CHECK_VERSION(3, 0, 0) new_last_modified_str = soup_message_headers_get_one (soup_message_get_response_headers (data->message), "Last-Modified"); #else new_last_modified_str = soup_message_headers_get_one (data->message->response_headers, "Last-Modified"); #endif if (new_last_modified_str != NULL && *new_last_modified_str == '\0') new_last_modified_str = NULL; if (new_last_modified_str != NULL) data->new_last_modified_date = date_time_from_rfc7231 (new_last_modified_str); } else { g_assert_not_reached (); } /* Splice in an asynchronous loop. We unfortunately can’t use * g_output_stream_splice_async() here, as it doesn’t provide a progress * callback. The approach is the same though. */ g_input_stream_read_bytes_async (input_stream, data->buffer_size_bytes, data->io_priority, cancellable, read_bytes_cb, g_steal_pointer (&task)); } static void read_bytes_cb (GObject *source_object, GAsyncResult *result, gpointer user_data) { GInputStream *input_stream = G_INPUT_STREAM (source_object); g_autoptr(GTask) task = g_steal_pointer (&user_data); DownloadData *data = g_task_get_task_data (task); GCancellable *cancellable = g_task_get_cancellable (task); g_autoptr(GBytes) bytes = NULL; g_autoptr(GError) local_error = NULL; bytes = g_input_stream_read_bytes_finish (input_stream, result, &local_error); if (bytes == NULL) { finish_download (task, g_steal_pointer (&local_error)); return; } /* Report progress. */ data->total_read_bytes += g_bytes_get_size (bytes); data->expected_stream_size_bytes = MAX (data->expected_stream_size_bytes, data->total_read_bytes); download_progress (task); /* Write the downloaded data. */ if (g_bytes_get_size (bytes) > 0) { g_clear_pointer (&data->currently_unwritten_chunk, g_bytes_unref); data->currently_unwritten_chunk = g_bytes_ref (bytes); g_output_stream_write_bytes_async (data->output_stream, bytes, data->io_priority, cancellable, write_bytes_cb, g_steal_pointer (&task)); } else { finish_download (task, NULL); } } static void write_bytes_cb (GObject *source_object, GAsyncResult *result, gpointer user_data) { GOutputStream *output_stream = G_OUTPUT_STREAM (source_object); g_autoptr(GTask) task = g_steal_pointer (&user_data); DownloadData *data = g_task_get_task_data (task); GCancellable *cancellable = g_task_get_cancellable (task); gssize bytes_written_signed; gsize bytes_written; g_autoptr(GError) local_error = NULL; bytes_written_signed = g_output_stream_write_bytes_finish (output_stream, result, &local_error); if (bytes_written_signed < 0) { finish_download (task, g_steal_pointer (&local_error)); return; } /* We know this is non-negative now. */ bytes_written = (gsize) bytes_written_signed; /* Report progress. */ data->total_written_bytes += bytes_written; download_progress (task); g_assert (data->currently_unwritten_chunk != NULL); if (bytes_written < g_bytes_get_size (data->currently_unwritten_chunk)) { /* Partial write; try again with the remaining bytes. */ g_autoptr(GBytes) sub_bytes = g_bytes_new_from_bytes (data->currently_unwritten_chunk, bytes_written, g_bytes_get_size (data->currently_unwritten_chunk) - bytes_written); g_assert (bytes_written > 0); g_clear_pointer (&data->currently_unwritten_chunk, g_bytes_unref); data->currently_unwritten_chunk = g_bytes_ref (sub_bytes); g_output_stream_write_bytes_async (output_stream, sub_bytes, data->io_priority, cancellable, write_bytes_cb, g_steal_pointer (&task)); } else { /* Full write succeeded. Start the next read. */ g_clear_pointer (&data->currently_unwritten_chunk, g_bytes_unref); g_input_stream_read_bytes_async (data->input_stream, data->buffer_size_bytes, data->io_priority, cancellable, read_bytes_cb, g_steal_pointer (&task)); } } static inline gboolean is_not_modidifed_error (GError *error) { return g_error_matches (error, GS_DOWNLOAD_ERROR, GS_DOWNLOAD_ERROR_NOT_MODIFIED); } /* error is (transfer full) */ static void finish_download (GTask *task, GError *error) { DownloadData *data = g_task_get_task_data (task); GCancellable *cancellable = g_task_get_cancellable (task); /* Final progress update. */ if (error == NULL || is_not_modidifed_error (error)) { data->expected_stream_size_bytes = data->total_read_bytes; download_progress (task); } /* Record the error from the operation, if set. */ g_assert (data->error == NULL); data->error = g_steal_pointer (&error); g_assert (!data->discard_output_stream || data->close_output_stream); if (data->close_output_stream) { g_autoptr(GCancellable) output_cancellable = NULL; g_assert (data->output_stream != NULL); /* If there’s been a prior error, or we are aborting writing the * output stream (perhaps because of a cache hit), close the * output stream but cancel the close operation so that the old * output file is not overwritten. */ if ((data->error != NULL && !is_not_modidifed_error (data->error)) || data->discard_output_stream) { output_cancellable = g_cancellable_new (); g_cancellable_cancel (output_cancellable); } else if (g_task_get_cancellable (task) != NULL) { output_cancellable = g_object_ref (g_task_get_cancellable (task)); } g_output_stream_close_async (data->output_stream, data->io_priority, output_cancellable, close_stream_cb, g_object_ref (task)); } if (data->close_input_stream && data->input_stream != NULL) { g_input_stream_close_async (data->input_stream, data->io_priority, cancellable, close_stream_cb, g_object_ref (task)); } /* Check in case both streams are already closed. */ close_stream_cb (NULL, NULL, g_object_ref (task)); } static void close_stream_cb (GObject *source_object, GAsyncResult *result, gpointer user_data) { g_autoptr(GTask) task = g_steal_pointer (&user_data); DownloadData *data = g_task_get_task_data (task); g_autoptr(GError) local_error = NULL; if (G_IS_INPUT_STREAM (source_object)) { /* Errors in closing the input stream are not fatal. */ if (!g_input_stream_close_finish (G_INPUT_STREAM (source_object), result, &local_error)) g_debug ("Error closing input stream: %s", local_error->message); g_clear_error (&local_error); data->close_input_stream = FALSE; } else if (G_IS_OUTPUT_STREAM (source_object)) { /* Errors in closing the output stream are fatal, but don’t * overwrite errors set earlier in the operation. */ if (!g_output_stream_close_finish (G_OUTPUT_STREAM (source_object), result, &local_error)) { /* If we are aborting writing the output stream (perhaps * because of a cache hit), don’t report the error at * all. */ if (data->discard_output_stream && g_error_matches (local_error, G_IO_ERROR, G_IO_ERROR_CANCELLED)) g_clear_error (&local_error); else if (data->error == NULL) data->error = g_steal_pointer (&local_error); else if (!g_error_matches (local_error, G_IO_ERROR, G_IO_ERROR_CANCELLED)) g_debug ("Error closing output stream: %s", local_error->message); } g_clear_error (&local_error); data->close_output_stream = FALSE; data->discard_output_stream = FALSE; } else { /* finish_download() calls this with a NULL source_object */ } /* Still waiting for one of the streams to close? */ if (data->close_input_stream || data->close_output_stream) return; if (data->error != NULL) { g_task_return_error (task, g_error_copy (data->error)); } else { g_task_return_boolean (task, TRUE); } } static void download_progress (GTask *task) { DownloadData *data = g_task_get_task_data (task); if (data->progress_callback != NULL) { /* This should be guaranteed by the rest of the download code. */ g_assert (data->expected_stream_size_bytes >= data->total_written_bytes); data->progress_callback (data->total_written_bytes, data->expected_stream_size_bytes, data->progress_user_data); } } /** * gs_download_stream_finish: * @soup_session: a #SoupSession * @result: result of the asynchronous operation * @new_etag_out: (out callee-allocates) (transfer full) (optional) (nullable): * return location for the ETag of the downloaded file (which may be %NULL), * or %NULL to ignore it * @new_last_modified_date_out: (out callee-allocates) (transfer full) (optional) (nullable): * return location for the new Last-Modified date of the downloaded file * (which may be %NULL), or %NULL to ignore it * @error: return location for a #GError * * Finish an asynchronous download operation started with * gs_download_stream_async(). * * Returns: %TRUE on success, %FALSE otherwise * Since: 43 */ gboolean gs_download_stream_finish (SoupSession *soup_session, GAsyncResult *result, gchar **new_etag_out, GDateTime **new_last_modified_date_out, GError **error) { DownloadData *data; g_return_val_if_fail (g_task_is_valid (result, soup_session), FALSE); g_return_val_if_fail (g_task_get_source_tag (G_TASK (result)) == gs_download_stream_async, FALSE); g_return_val_if_fail (error == NULL || *error == NULL, FALSE); data = g_task_get_task_data (G_TASK (result)); if (new_etag_out != NULL) *new_etag_out = g_strdup (data->new_etag); if (new_last_modified_date_out != NULL) *new_last_modified_date_out = (data->new_last_modified_date != NULL) ? g_date_time_ref (data->new_last_modified_date) : NULL; return g_task_propagate_boolean (G_TASK (result), error); } typedef struct { /* Input data. */ gchar *uri; /* (not nullable) (owned) */ GFile *output_file; /* (not nullable) (owned) */ int io_priority; GsDownloadProgressCallback progress_callback; gpointer progress_user_data; /* In-progress data. */ gchar *last_etag; /* (nullable) (owned) */ GDateTime *last_modified_date; /* (nullable) (owned) */ } DownloadFileData; static void download_file_data_free (DownloadFileData *data) { g_free (data->uri); g_clear_object (&data->output_file); g_free (data->last_etag); g_clear_pointer (&data->last_modified_date, g_date_time_unref); g_free (data); } G_DEFINE_AUTOPTR_CLEANUP_FUNC (DownloadFileData, download_file_data_free) static void download_replace_file_cb (GObject *source_object, GAsyncResult *result, gpointer user_data); static void download_file_cb (GObject *source_object, GAsyncResult *result, gpointer user_data); /** * gs_download_file_async: * @soup_session: a #SoupSession * @uri: (not nullable): the URI to download * @output_file: (not nullable): an output file to write the download to * @io_priority: I/O priority to download and write at * @progress_callback: (nullable): callback to call with progress information * @progress_user_data: (nullable) (closure progress_callback): data to pass * to @progress_callback * @cancellable: (nullable): a #GCancellable, or %NULL * @callback: callback to call once the operation is complete * @user_data: (closure callback): data to pass to @callback * * Download @uri and write it to @output_file asynchronously, overwriting the * existing content of @output_file. * * The ETag and modification time of @output_file will be queried and, if known, * used to skip the download if @output_file is already up to date. * * If specified, @progress_callback will be called zero or more times until * @callback is called, providing progress updates on the download. * * Since: 42 */ void gs_download_file_async (SoupSession *soup_session, const gchar *uri, GFile *output_file, int io_priority, GsDownloadProgressCallback progress_callback, gpointer progress_user_data, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer user_data) { g_autoptr(GTask) task = NULL; DownloadFileData *data; g_autoptr(DownloadFileData) data_owned = NULL; g_autoptr(GFile) output_file_parent = NULL; g_autoptr(GError) local_error = NULL; g_return_if_fail (SOUP_IS_SESSION (soup_session)); g_return_if_fail (uri != NULL); g_return_if_fail (G_IS_FILE (output_file)); g_return_if_fail (cancellable == NULL || G_IS_CANCELLABLE (cancellable)); task = g_task_new (soup_session, cancellable, callback, user_data); g_task_set_source_tag (task, gs_download_file_async); data = data_owned = g_new0 (DownloadFileData, 1); data->uri = g_strdup (uri); data->output_file = g_object_ref (output_file); data->io_priority = io_priority; data->progress_callback = progress_callback; data->progress_user_data = progress_user_data; g_task_set_task_data (task, g_steal_pointer (&data_owned), (GDestroyNotify) download_file_data_free); /* Create the destination file’s directory. * FIXME: This should be made async; it hasn’t done for now as it’s * likely to be fast. */ output_file_parent = g_file_get_parent (output_file); if (output_file_parent != NULL && !g_file_make_directory_with_parents (output_file_parent, cancellable, &local_error) && !g_error_matches (local_error, G_IO_ERROR, G_IO_ERROR_EXISTS)) { g_task_return_error (task, g_steal_pointer (&local_error)); return; } g_clear_error (&local_error); /* Query the old ETag and modification date if the file already exists. */ data->last_etag = gs_utils_get_file_etag (output_file, &data->last_modified_date, cancellable); /* Create the output file. * * Note that `data->last_etag` is *not* passed in here, as the ETag from * the server and the file modification ETag that GLib uses are * different things. For g_file_replace_async(), GLib always uses an * ETag it generates internally based on the file mtime (see * _g_local_file_info_create_etag()), which will never match what the * server returns in its ETag header. * * This is fine, as we are using the ETag to avoid an unnecessary HTTP * download if possible. We don’t care about tracking changes to the * file on disk. */ g_file_replace_async (output_file, NULL, /* ETag */ FALSE, /* make_backup */ G_FILE_CREATE_PRIVATE | G_FILE_CREATE_REPLACE_DESTINATION, io_priority, cancellable, download_replace_file_cb, g_steal_pointer (&task)); } static void download_replace_file_cb (GObject *source_object, GAsyncResult *result, gpointer user_data) { GFile *output_file = G_FILE (source_object); g_autoptr(GTask) task = g_steal_pointer (&user_data); SoupSession *soup_session = g_task_get_source_object (task); GCancellable *cancellable = g_task_get_cancellable (task); DownloadFileData *data = g_task_get_task_data (task); g_autoptr(GFileOutputStream) output_stream = NULL; g_autoptr(GError) local_error = NULL; output_stream = g_file_replace_finish (output_file, result, &local_error); if (output_stream == NULL) { g_task_return_error (task, g_steal_pointer (&local_error)); return; } /* Do the download. */ gs_download_stream_async (soup_session, data->uri, G_OUTPUT_STREAM (output_stream), data->last_etag, data->last_modified_date, data->io_priority, data->progress_callback, data->progress_user_data, cancellable, download_file_cb, g_steal_pointer (&task)); } static void download_file_cb (GObject *source_object, GAsyncResult *result, gpointer user_data) { SoupSession *soup_session = SOUP_SESSION (source_object); g_autoptr(GTask) task = g_steal_pointer (&user_data); GCancellable *cancellable = g_task_get_cancellable (task); DownloadFileData *data = g_task_get_task_data (task); g_autofree gchar *new_etag = NULL; g_autoptr(GError) local_error = NULL; if (!gs_download_stream_finish (soup_session, result, &new_etag, NULL, &local_error)) { g_task_return_error (task, g_steal_pointer (&local_error)); return; } /* Update the stored HTTP ETag. * * Under the assumption that this code is only ever used for locally * cached copies of remote files (i.e. the local copies are never * modified except by downloading an updated version from the server), * it’s safe to use the local file modification date for Last-Modified, * and save having to update that explicitly. This is because the * modification time of the local file equals when gnome-software last * checked for updates to it — which is correct to send as the * If-Modified-Since the next time gnome-software checks for updates to * the file. */ gs_utils_set_file_etag (data->output_file, new_etag, cancellable); g_task_return_boolean (task, TRUE); } /** * gs_download_file_finish: * @soup_session: a #SoupSession * @result: result of the asynchronous operation * @error: return location for a #GError * * Finish an asynchronous download operation started with * gs_download_file_async(). * * Returns: %TRUE on success, %FALSE otherwise * Since: 42 */ gboolean gs_download_file_finish (SoupSession *soup_session, GAsyncResult *result, GError **error) { g_return_val_if_fail (g_task_is_valid (result, soup_session), FALSE); g_return_val_if_fail (g_task_get_source_tag (G_TASK (result)) == gs_download_file_async, FALSE); g_return_val_if_fail (error == NULL || *error == NULL, FALSE); return g_task_propagate_boolean (G_TASK (result), error); }