diff options
Diffstat (limited to 'src/input/rewind_input_plugin.c')
-rw-r--r-- | src/input/rewind_input_plugin.c | 256 |
1 files changed, 0 insertions, 256 deletions
diff --git a/src/input/rewind_input_plugin.c b/src/input/rewind_input_plugin.c deleted file mode 100644 index cf06fc57b..000000000 --- a/src/input/rewind_input_plugin.c +++ /dev/null @@ -1,256 +0,0 @@ -/* - * Copyright (C) 2003-2011 The Music Player Daemon Project - * http://www.musicpd.org - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program 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 General Public License for more details. - * - * You should have received a copy of the GNU General Public License along - * with this program; if not, write to the Free Software Foundation, Inc., - * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. - */ - -#include "config.h" -#include "input/rewind_input_plugin.h" -#include "input_internal.h" -#include "input_plugin.h" -#include "tag.h" - -#include <glib.h> - -#include <assert.h> -#include <stdio.h> - -#undef G_LOG_DOMAIN -#define G_LOG_DOMAIN "input_rewind" - -struct input_rewind { - struct input_stream base; - - struct input_stream *input; - - /** - * The read position within the buffer. Undefined as long as - * reading_from_buffer() returns false. - */ - size_t head; - - /** - * The write/append position within the buffer. - */ - size_t tail; - - /** - * The size of this buffer is the maximum number of bytes - * which can be rewinded cheaply without passing the "seek" - * call to CURL. - * - * The origin of this buffer is always the beginning of the - * stream (offset 0). - */ - char buffer[64 * 1024]; -}; - -/** - * Are we currently reading from the buffer, and does the buffer - * contain more data for the next read operation? - */ -static bool -reading_from_buffer(const struct input_rewind *r) -{ - return r->tail > 0 && r->base.offset < r->input->offset; -} - -/** - * Copy public attributes from the underlying input stream to the - * "rewind" input stream. This function is called when a method of - * the underlying stream has returned, which may have modified these - * attributes. - */ -static void -copy_attributes(struct input_rewind *r) -{ - struct input_stream *dest = &r->base; - const struct input_stream *src = r->input; - - assert(dest != src); - assert(src->mime == NULL || dest->mime != src->mime); - - bool dest_ready = dest->ready; - - dest->ready = src->ready; - dest->seekable = src->seekable; - dest->size = src->size; - dest->offset = src->offset; - - if (!dest_ready && src->ready) { - g_free(dest->mime); - dest->mime = g_strdup(src->mime); - } -} - -static void -input_rewind_close(struct input_stream *is) -{ - struct input_rewind *r = (struct input_rewind *)is; - - input_stream_close(r->input); - - input_stream_deinit(&r->base); - g_free(r); -} - -static bool -input_rewind_check(struct input_stream *is, GError **error_r) -{ - struct input_rewind *r = (struct input_rewind *)is; - - return input_stream_check(r->input, error_r); -} - -static void -input_rewind_update(struct input_stream *is) -{ - struct input_rewind *r = (struct input_rewind *)is; - - if (!reading_from_buffer(r)) - copy_attributes(r); -} - -static struct tag * -input_rewind_tag(struct input_stream *is) -{ - struct input_rewind *r = (struct input_rewind *)is; - - return input_stream_tag(r->input); -} - -static bool -input_rewind_available(struct input_stream *is) -{ - struct input_rewind *r = (struct input_rewind *)is; - - return input_stream_available(r->input); -} - -static size_t -input_rewind_read(struct input_stream *is, void *ptr, size_t size, - GError **error_r) -{ - struct input_rewind *r = (struct input_rewind *)is; - - if (reading_from_buffer(r)) { - /* buffered read */ - - assert(r->head == (size_t)is->offset); - assert(r->tail == (size_t)r->input->offset); - - if (size > r->tail - r->head) - size = r->tail - r->head; - - memcpy(ptr, r->buffer + r->head, size); - r->head += size; - is->offset += size; - - return size; - } else { - /* pass method call to underlying stream */ - - size_t nbytes = input_stream_read(r->input, ptr, size, error_r); - - if (r->input->offset > (goffset)sizeof(r->buffer)) - /* disable buffering */ - r->tail = 0; - else if (r->tail == (size_t)is->offset) { - /* append to buffer */ - - memcpy(r->buffer + r->tail, ptr, nbytes); - r->tail += nbytes; - - assert(r->tail == (size_t)r->input->offset); - } - - copy_attributes(r); - - return nbytes; - } -} - -static bool -input_rewind_eof(struct input_stream *is) -{ - struct input_rewind *r = (struct input_rewind *)is; - - return !reading_from_buffer(r) && input_stream_eof(r->input); -} - -static bool -input_rewind_seek(struct input_stream *is, goffset offset, int whence, - GError **error_r) -{ - struct input_rewind *r = (struct input_rewind *)is; - - assert(is->ready); - - if (whence == SEEK_SET && r->tail > 0 && offset <= (goffset)r->tail) { - /* buffered seek */ - - assert(!reading_from_buffer(r) || - r->head == (size_t)is->offset); - assert(r->tail == (size_t)r->input->offset); - - r->head = (size_t)offset; - is->offset = offset; - - return true; - } else { - bool success = input_stream_seek(r->input, offset, whence, - error_r); - copy_attributes(r); - - /* disable the buffer, because r->input has left the - buffered range now */ - r->tail = 0; - - return success; - } -} - -static const struct input_plugin rewind_input_plugin = { - .close = input_rewind_close, - .check = input_rewind_check, - .update = input_rewind_update, - .tag = input_rewind_tag, - .available = input_rewind_available, - .read = input_rewind_read, - .eof = input_rewind_eof, - .seek = input_rewind_seek, -}; - -struct input_stream * -input_rewind_open(struct input_stream *is) -{ - struct input_rewind *c; - - assert(is != NULL); - assert(is->offset == 0); - - if (is->seekable) - /* seekable resources don't need this plugin */ - return is; - - c = g_new(struct input_rewind, 1); - input_stream_init(&c->base, &rewind_input_plugin, is->uri, - is->mutex, is->cond); - c->tail = 0; - c->input = is; - - return &c->base; -} |