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mpv/stream/stream.c

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/*
* This file is part of mpv.
*
* mpv 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 2.1 of the License, or (at your option) any later version.
*
* mpv 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 mpv. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdio.h>
#include <stdlib.h>
#include <limits.h>
#include <strings.h>
#include <assert.h>
#include <libavutil/common.h>
#include "osdep/io.h"
#include "mpv_talloc.h"
#include "config.h"
#include "common/common.h"
#include "common/global.h"
#include "misc/bstr.h"
#include "misc/thread_tools.h"
#include "common/msg.h"
#include "options/options.h"
#include "options/path.h"
#include "osdep/timer.h"
#include "stream.h"
#include "options/m_option.h"
#include "options/m_config.h"
extern const stream_info_t stream_info_cdda;
extern const stream_info_t stream_info_dvb;
extern const stream_info_t stream_info_smb;
extern const stream_info_t stream_info_null;
extern const stream_info_t stream_info_memory;
extern const stream_info_t stream_info_mf;
extern const stream_info_t stream_info_ffmpeg;
extern const stream_info_t stream_info_ffmpeg_unsafe;
extern const stream_info_t stream_info_avdevice;
extern const stream_info_t stream_info_file;
extern const stream_info_t stream_info_ifo_dvdnav;
extern const stream_info_t stream_info_dvdnav;
extern const stream_info_t stream_info_bdmv_dir;
extern const stream_info_t stream_info_bluray;
extern const stream_info_t stream_info_bdnav;
extern const stream_info_t stream_info_edl;
extern const stream_info_t stream_info_libarchive;
extern const stream_info_t stream_info_cb;
static const stream_info_t *const stream_list[] = {
#if HAVE_CDDA
&stream_info_cdda,
#endif
&stream_info_ffmpeg,
&stream_info_ffmpeg_unsafe,
&stream_info_avdevice,
#if HAVE_DVBIN
&stream_info_dvb,
#endif
#if HAVE_LIBSMBCLIENT
&stream_info_smb,
#endif
#if HAVE_DVDNAV
&stream_info_ifo_dvdnav,
&stream_info_dvdnav,
#endif
#if HAVE_LIBBLURAY
&stream_info_bdmv_dir,
&stream_info_bluray,
&stream_info_bdnav,
#endif
#if HAVE_LIBARCHIVE
&stream_info_libarchive,
#endif
&stream_info_memory,
&stream_info_null,
&stream_info_mf,
&stream_info_edl,
&stream_info_file,
&stream_info_cb,
NULL
};
static bool stream_seek_unbuffered(stream_t *s, int64_t newpos);
// return -1 if not hex char
static int hex2dec(char c)
{
if (c >= '0' && c <= '9')
return c - '0';
if (c >= 'A' && c <= 'F')
return 10 + c - 'A';
if (c >= 'a' && c <= 'f')
return 10 + c - 'a';
return -1;
}
// Replace escape sequences in an URL (or a part of an URL)
void mp_url_unescape_inplace(char *url)
{
for (int len = strlen(url), i = 0, o = 0; i <= len;) {
if ((url[i] != '%') || (i > len - 3)) { // %NN can't start after len-3
url[o++] = url[i++];
continue;
}
int msd = hex2dec(url[i + 1]),
lsd = hex2dec(url[i + 2]);
if (msd >= 0 && lsd >= 0) {
url[o++] = 16 * msd + lsd;
i += 3;
} else {
url[o++] = url[i++];
url[o++] = url[i++];
url[o++] = url[i++];
}
}
}
static const char hex_digits[] = "0123456789ABCDEF";
static const char url_default_ok[] = "abcdefghijklmnopqrstuvwxyz"
"ABCDEFGHIJKLMNOPQRSTUVWXYZ"
"0123456789"
"-._~";
// Escape according to http://tools.ietf.org/html/rfc3986#section-2.1
// Only unreserved characters are not escaped.
// The argument ok (if not NULL) is as follows:
// ok[0] != '~': additional characters that are not escaped
// ok[0] == '~': do not escape anything but these characters
// (can't override the unreserved characters, which are
// never escaped)
char *mp_url_escape(void *talloc_ctx, const char *url, const char *ok)
{
char *rv = talloc_size(talloc_ctx, strlen(url) * 3 + 1);
char *out = rv;
bool negate = ok && ok[0] == '~';
for (char c; (c = *url); url++) {
bool as_is = negate ? !strchr(ok + 1, c)
: (strchr(url_default_ok, c) || (ok && strchr(ok, c)));
if (as_is) {
*out++ = c;
} else {
unsigned char v = c;
*out++ = '%';
*out++ = hex_digits[v / 16];
*out++ = hex_digits[v % 16];
}
}
*out = 0;
return rv;
}
static const char *match_proto(const char *url, const char *proto)
{
int l = strlen(proto);
if (l > 0) {
if (strncasecmp(url, proto, l) == 0 && strncmp("://", url + l, 3) == 0)
return url + l + 3;
} else if (!mp_is_url(bstr0(url))) {
return url; // pure filenames
}
return NULL;
}
// Resize the current stream buffer, or do nothing if the size is adequate.
// Caller must ensure the used buffer is not less than the new buffer size.
// Calling this with 0 ensures it uses the default buffer size.
static void stream_resize_buffer(struct stream *s, int new)
{
new = MPMAX(new, STREAM_BUFFER_SIZE);
if (new == s->buffer_alloc)
return;
int buffer_used = s->buf_len - s->buf_pos;
assert(buffer_used <= new);
void *nbuf = s->buffer_inline;
if (new > STREAM_BUFFER_SIZE)
nbuf = ta_alloc_size(s, new);
if (nbuf) {
if (s->buffer)
memmove(nbuf, &s->buffer[s->buf_pos], buffer_used);
s->buf_pos = 0;
s->buf_len = buffer_used;
if (s->buffer != s->buffer_inline)
ta_free(s->buffer);
s->buffer = nbuf;
s->buffer_alloc = new;
}
}
static int stream_create_instance(const stream_info_t *sinfo,
struct stream_open_args *args,
struct stream **ret)
{
const char *url = args->url;
int flags = args->flags;
*ret = NULL;
if (!sinfo->is_safe && (flags & STREAM_SAFE_ONLY))
return STREAM_UNSAFE;
if (!sinfo->is_network && (flags & STREAM_NETWORK_ONLY))
return STREAM_UNSAFE;
const char *path = url;
for (int n = 0; sinfo->protocols && sinfo->protocols[n]; n++) {
path = match_proto(url, sinfo->protocols[n]);
if (path)
break;
}
if (!path)
return STREAM_NO_MATCH;
stream_t *s = talloc_zero(NULL, stream_t);
s->global = args->global;
if (flags & STREAM_SILENT) {
s->log = mp_null_log;
} else {
s->log = mp_log_new(s, s->global->log, sinfo->name);
}
s->info = sinfo;
s->cancel = args->cancel;
s->url = talloc_strdup(s, url);
s->path = talloc_strdup(s, path);
s->is_network = sinfo->is_network;
s->mode = flags & (STREAM_READ | STREAM_WRITE);
int opt;
mp_read_option_raw(s->global, "access-references", &m_option_type_flag, &opt);
s->access_references = opt;
MP_VERBOSE(s, "Opening %s\n", url);
if (strlen(url) > INT_MAX / 8) {
MP_ERR(s, "URL too large.\n");
talloc_free(s);
return STREAM_ERROR;
}
if ((s->mode & STREAM_WRITE) && !sinfo->can_write) {
MP_DBG(s, "No write access implemented.\n");
talloc_free(s);
return STREAM_NO_MATCH;
}
int r = STREAM_UNSUPPORTED;
if (sinfo->open2) {
r = sinfo->open2(s, args);
} else if (!args->special_arg) {
r = (sinfo->open)(s);
}
if (r != STREAM_OK) {
talloc_free(s);
return r;
}
if (!s->read_chunk)
s->read_chunk = 4 * STREAM_BUFFER_SIZE;
stream_resize_buffer(s, 0);
MP_HANDLE_OOM(s->buffer);
assert(s->seekable == !!s->seek);
if (s->mime_type)
MP_VERBOSE(s, "Mime-type: '%s'\n", s->mime_type);
MP_DBG(s, "Stream opened successfully.\n");
*ret = s;
return STREAM_OK;
}
int stream_create_with_args(struct stream_open_args *args, struct stream **ret)
{
assert(args->url);
int r = STREAM_NO_MATCH;
*ret = NULL;
// Open stream proper
if (args->sinfo) {
r = stream_create_instance(args->sinfo, args, ret);
} else {
for (int i = 0; stream_list[i]; i++) {
r = stream_create_instance(stream_list[i], args, ret);
if (r == STREAM_OK)
break;
if (r == STREAM_NO_MATCH || r == STREAM_UNSUPPORTED)
continue;
if (r == STREAM_UNSAFE)
continue;
break;
}
}
if (!*ret && !(args->flags & STREAM_SILENT) && !mp_cancel_test(args->cancel))
{
struct mp_log *log = mp_log_new(NULL, args->global->log, "!stream");
if (r == STREAM_UNSAFE) {
mp_err(log, "\nRefusing to load potentially unsafe URL from a playlist.\n"
"Use --playlist=file or the --load-unsafe-playlists option to "
"load it anyway.\n\n");
} else if (r == STREAM_NO_MATCH || r == STREAM_UNSUPPORTED) {
mp_err(log, "No protocol handler found to open URL %s\n", args->url);
mp_err(log, "The protocol is either unsupported, or was disabled "
"at compile-time.\n");
} else {
mp_err(log, "Failed to open %s.\n", args->url);
}
talloc_free(log);
}
return r;
}
struct stream *stream_create(const char *url, int flags,
struct mp_cancel *c, struct mpv_global *global)
{
struct stream_open_args args = {
.global = global,
.cancel = c,
.flags = flags,
.url = url,
};
struct stream *s;
stream_create_with_args(&args, &s);
return s;
}
struct stream *stream_open(const char *filename, struct mpv_global *global)
{
return stream_create(filename, STREAM_READ, NULL, global);
}
stream_t *open_output_stream(const char *filename, struct mpv_global *global)
{
return stream_create(filename, STREAM_WRITE, NULL, global);
}
// Read function bypassing the local stream buffer. This will not write into
// s->buffer, but into buf[0..len] instead.
// Returns 0 on error or EOF, and length of bytes read on success.
// Partial reads are possible, even if EOF is not reached.
static int stream_read_unbuffered(stream_t *s, void *buf, int len)
{
assert(len >= 0);
if (len <= 0)
return 0;
int res = 0;
// we will retry even if we already reached EOF previously.
if (s->fill_buffer && !mp_cancel_test(s->cancel))
res = s->fill_buffer(s, buf, len);
if (res <= 0) {
s->eof = 1;
return 0;
}
// When reading succeeded we are obviously not at eof.
s->eof = 0;
s->pos += res;
s->total_unbuffered_read_bytes += res;
return res;
}
// Ask for having "total" bytes ready to read in the stream buffer. This can do
// a partial read if requested, so it can actually read less.
// To read everything, you may have to call this in a loop.
// total: desired amount of bytes in buffer
// allow_short: if true, attempt at most once to read more if needed
// returns: actual bytes in buffer (can be smaller or larger than total)
static int stream_extend_buffer(struct stream *s, int total, bool allow_short)
{
assert(total >= 0);
if (s->buf_len - s->buf_pos < total) {
// Move to front to guarantee we really can read up to max size.
s->buf_len = s->buf_len - s->buf_pos;
memmove(s->buffer, &s->buffer[s->buf_pos], s->buf_len);
s->buf_pos = 0;
// Read ahead by about as much as stream_fill_buffer() would, to avoid
// that many small stream_peek() calls will read the buffer at these
// quantities.
total = MPMAX(total, STREAM_BUFFER_SIZE);
// Allocate more if the buffer is too small. Also, if the buffer is
// larger than needed, resize it to smaller. This assumes stream_peek()
// calls are rare or done with small sizes.
stream_resize_buffer(s, total);
// Read less if allocation above failed.
total = MPMIN(total, s->buffer_alloc);
// Fill rest of the buffer. Can be partial.
while (total > s->buf_len) {
int read = stream_read_unbuffered(s, &s->buffer[s->buf_len],
total - s->buf_len);
s->buf_len += read;
if (allow_short || !read)
break;
}
if (s->buf_len)
s->eof = 0;
}
return s->buf_len - s->buf_pos;
}
int stream_fill_buffer(stream_t *s)
{
return stream_extend_buffer(s, STREAM_BUFFER_SIZE, true);
}
// Read between 1..buf_size bytes of data, return how much data has been read.
// Return 0 on EOF, error, or if buf_size was 0.
int stream_read_partial(stream_t *s, char *buf, int buf_size)
{
assert(s->buf_pos <= s->buf_len);
assert(buf_size >= 0);
if (s->buf_pos == s->buf_len && buf_size > 0) {
s->buf_pos = s->buf_len = 0;
stream_resize_buffer(s, 0);
// Do a direct read
// Also, small reads will be more efficient with buffering & copying
if (buf_size >= STREAM_BUFFER_SIZE)
return stream_read_unbuffered(s, buf, buf_size);
if (!stream_fill_buffer(s))
return 0;
}
int len = FFMIN(buf_size, s->buf_len - s->buf_pos);
memcpy(buf, &s->buffer[s->buf_pos], len);
s->buf_pos += len;
if (len > 0)
s->eof = 0;
return len;
}
int stream_read(stream_t *s, char *mem, int total)
{
int len = total;
while (len > 0) {
int read = stream_read_partial(s, mem, len);
if (read <= 0)
break; // EOF
mem += read;
len -= read;
}
total -= len;
if (total > 0)
s->eof = 0;
return total;
}
// Read ahead at most len bytes without changing the read position. Return a
// pointer to the internal buffer, starting from the current read position.
// Reading ahead may require memory allocation. If allocation fails, read ahead
// is silently limited to the last successful allocation.
// The returned buffer becomes invalid on the next stream call, and you must
// not write to it.
struct bstr stream_peek(stream_t *s, int len)
{
assert(len >= 0);
int avail = stream_extend_buffer(s, len, false);
return (bstr){.start = &s->buffer[s->buf_pos], .len = MPMIN(len, avail)};
}
int stream_write_buffer(stream_t *s, unsigned char *buf, int len)
{
if (!s->write_buffer)
return -1;
int orig_len = len;
while (len) {
int w = s->write_buffer(s, buf, len);
if (w <= 0)
return -1;
s->pos += w;
buf += w;
len -= w;
}
return orig_len;
}
// Drop len bytes form input, possibly reading more until all is skipped. If
// EOF or an error was encountered before all could be skipped, return false,
// otherwise return true.
static bool stream_skip_read(struct stream *s, int64_t len)
{
while (len > 0) {
unsigned int left = s->buf_len - s->buf_pos;
if (!left) {
if (!stream_fill_buffer(s))
return false;
continue;
}
unsigned skip = MPMIN(len, left);
s->buf_pos += skip;
len -= skip;
}
return true;
}
// Drop the internal buffer. Note that this will advance the stream position
// (as seen by stream_tell()), because the real stream position is ahead of the
// logical stream position by the amount of buffered but not yet read data.
void stream_drop_buffers(stream_t *s)
{
s->pos = stream_tell(s);
s->buf_pos = s->buf_len = 0;
s->eof = 0;
stream_resize_buffer(s, 0);
}
// Seek function bypassing the local stream buffer.
static bool stream_seek_unbuffered(stream_t *s, int64_t newpos)
{
if (newpos != s->pos) {
if (newpos > s->pos && !s->seekable) {
MP_ERR(s, "Cannot seek forward in this stream\n");
return false;
}
if (newpos < s->pos && !s->seekable) {
MP_ERR(s, "Cannot seek backward in linear streams!\n");
return false;
}
if (s->seek(s, newpos) <= 0) {
int level = mp_cancel_test(s->cancel) ? MSGL_V : MSGL_ERR;
MP_MSG(s, level, "Seek failed (to %lld, size %lld)\n",
(long long)newpos, (long long)stream_get_size(s));
return false;
}
stream_drop_buffers(s);
s->pos = newpos;
}
return true;
}
bool stream_seek(stream_t *s, int64_t pos)
{
MP_TRACE(s, "seek to %lld\n", (long long)pos);
s->eof = 0; // eof should be set only on read; seeking always clears it
if (pos < 0) {
MP_ERR(s, "Invalid seek to negative position %lld!\n", (long long)pos);
pos = 0;
}
if (pos == stream_tell(s))
return true;
if (pos < s->pos) {
int64_t x = pos - (s->pos - (int)s->buf_len);
if (x >= 0) {
s->buf_pos = x;
assert(s->buf_pos <= s->buf_len);
return true;
}
}
if (s->mode == STREAM_WRITE)
return s->seekable && s->seek(s, pos);
int64_t newpos = pos;
MP_TRACE(s, "Seek from %" PRId64 " to %" PRId64
" (with offset %d)\n", s->pos, pos, (int)(pos - newpos));
if (pos >= s->pos && !s->seekable && s->fast_skip) {
// skipping is handled by generic code below
} else if (!stream_seek_unbuffered(s, newpos)) {
return false;
}
return stream_skip_read(s, pos - stream_tell(s));
}
bool stream_skip(stream_t *s, int64_t len)
{
int64_t target = stream_tell(s) + len;
if (len < 0)
return stream_seek(s, target);
if (len > 2 * STREAM_BUFFER_SIZE && s->seekable) {
// Seek to 1 byte before target - this is the only way to distinguish
// skip-to-EOF and skip-past-EOF in general. Successful seeking means
// absolutely nothing, so test by doing a real read of the last byte.
if (!stream_seek(s, target - 1))
return false;
stream_read_char(s);
return !stream_eof(s) && stream_tell(s) == target;
}
return stream_skip_read(s, len);
}
int stream_control(stream_t *s, int cmd, void *arg)
{
return s->control ? s->control(s, cmd, arg) : STREAM_UNSUPPORTED;
}
// Return the current size of the stream, or a negative value if unknown.
int64_t stream_get_size(stream_t *s)
{
int64_t size = -1;
if (stream_control(s, STREAM_CTRL_GET_SIZE, &size) != STREAM_OK)
size = -1;
return size;
}
void free_stream(stream_t *s)
{
if (!s)
return;
if (s->close)
s->close(s);
talloc_free(s);
}
static uint16_t stream_read_word_endian(stream_t *s, bool big_endian)
{
unsigned int y = stream_read_char(s);
y = (y << 8) | stream_read_char(s);
if (!big_endian)
y = ((y >> 8) & 0xFF) | (y << 8);
return y;
}
// Read characters until the next '\n' (including), or until the buffer in s is
// exhausted.
static int read_characters(stream_t *s, uint8_t *dst, int dstsize, int utf16)
{
if (utf16 == 1 || utf16 == 2) {
uint8_t *cur = dst;
while (1) {
if ((cur - dst) + 8 >= dstsize) // PUT_UTF8 writes max. 8 bytes
return -1; // line too long
uint32_t c;
uint8_t tmp;
GET_UTF16(c, stream_read_word_endian(s, utf16 == 2), return -1;)
if (s->eof)
break; // legitimate EOF; ignore the case of partial reads
PUT_UTF8(c, tmp, *cur++ = tmp;)
if (c == '\n')
break;
}
return cur - dst;
} else {
if (s->buf_pos >= s->buf_len)
stream_fill_buffer(s);
uint8_t *src = s->buffer + s->buf_pos;
int src_len = s->buf_len - s->buf_pos;
uint8_t *end = memchr(src, '\n', src_len);
int len = end ? end - src + 1 : src_len;
if (len > dstsize)
return -1; // line too long
memcpy(dst, src, len);
s->buf_pos += len;
return len;
}
}
// On error, or if the line is larger than max-1, return NULL and unset s->eof.
// On EOF, return NULL, and s->eof will be set.
// Otherwise, return the line (including \n or \r\n at the end of the line).
// If the return value is non-NULL, it's always the same as mem.
// utf16: 0: UTF8 or 8 bit legacy, 1: UTF16-LE, 2: UTF16-BE
unsigned char *stream_read_line(stream_t *s, unsigned char *mem, int max,
int utf16)
{
if (max < 1)
return NULL;
int read = 0;
while (1) {
// Reserve 1 byte of ptr for terminating \0.
int l = read_characters(s, &mem[read], max - read - 1, utf16);
if (l < 0 || memchr(&mem[read], '\0', l)) {
MP_WARN(s, "error reading line\n");
s->eof = false;
return NULL;
}
read += l;
if (l == 0 || (read > 0 && mem[read - 1] == '\n'))
break;
}
mem[read] = '\0';
if (s->eof && read == 0) // legitimate EOF
return NULL;
return mem;
}
static const char *const bom[3] = {"\xEF\xBB\xBF", "\xFF\xFE", "\xFE\xFF"};
// Return utf16 argument for stream_read_line
int stream_skip_bom(struct stream *s)
{
bstr data = stream_peek(s, 4);
for (int n = 0; n < 3; n++) {
if (bstr_startswith0(data, bom[n])) {
stream_skip(s, strlen(bom[n]));
return n;
}
}
return -1; // default to 8 bit codepages
}
// Read the rest of the stream into memory (current pos to EOF), and return it.
// talloc_ctx: used as talloc parent for the returned allocation
// max_size: must be set to >0. If the file is larger than that, it is treated
// as error. This is a minor robustness measure.
// returns: stream contents, or .start/.len set to NULL on error
// If the file was empty, but no error happened, .start will be non-NULL and
// .len will be 0.
// For convenience, the returned buffer is padded with a 0 byte. The padding
// is not included in the returned length.
struct bstr stream_read_complete(struct stream *s, void *talloc_ctx,
int max_size)
{
if (max_size > 1000000000)
abort();
int bufsize;
int total_read = 0;
int padding = 1;
char *buf = NULL;
int64_t size = stream_get_size(s) - stream_tell(s);
if (size > max_size)
return (struct bstr){NULL, 0};
if (size > 0)
bufsize = size + padding;
else
bufsize = 1000;
while (1) {
buf = talloc_realloc_size(talloc_ctx, buf, bufsize);
int readsize = stream_read(s, buf + total_read, bufsize - total_read);
total_read += readsize;
if (total_read < bufsize)
break;
if (bufsize > max_size) {
talloc_free(buf);
return (struct bstr){NULL, 0};
}
bufsize = FFMIN(bufsize + (bufsize >> 1), max_size + padding);
}
buf = talloc_realloc_size(talloc_ctx, buf, total_read + padding);
memset(&buf[total_read], 0, padding);
return (struct bstr){buf, total_read};
}
struct bstr stream_read_file(const char *filename, void *talloc_ctx,
struct mpv_global *global, int max_size)
{
struct bstr res = {0};
char *fname = mp_get_user_path(NULL, global, filename);
stream_t *s = stream_open(fname, global);
if (s) {
res = stream_read_complete(s, talloc_ctx, max_size);
free_stream(s);
}
talloc_free(fname);
return res;
}
char **stream_get_proto_list(void)
{
char **list = NULL;
int num = 0;
for (int i = 0; stream_list[i]; i++) {
const stream_info_t *stream_info = stream_list[i];
if (!stream_info->protocols)
continue;
for (int j = 0; stream_info->protocols[j]; j++) {
if (*stream_info->protocols[j] == '\0')
continue;
MP_TARRAY_APPEND(NULL, list, num,
talloc_strdup(NULL, stream_info->protocols[j]));
}
}
MP_TARRAY_APPEND(NULL, list, num, NULL);
return list;
}
void stream_print_proto_list(struct mp_log *log)
{
int count = 0;
mp_info(log, "Protocols:\n\n");
char **list = stream_get_proto_list();
for (int i = 0; list[i]; i++) {
mp_info(log, " %s://\n", list[i]);
count++;
talloc_free(list[i]);
}
talloc_free(list);
mp_info(log, "\nTotal: %d protocols\n", count);
}
bool stream_has_proto(const char *proto)
{
for (int i = 0; stream_list[i]; i++) {
const stream_info_t *stream_info = stream_list[i];
for (int j = 0; stream_info->protocols && stream_info->protocols[j]; j++) {
if (strcmp(stream_info->protocols[j], proto) == 0)
return true;
}
}
return false;
}
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