mpv/playtreeparser.c

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21 KiB
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/// \file
/// \ingroup PlaytreeParser
#include "config.h"
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <ctype.h>
#include "m_config.h"
#include "playtree.h"
#include "playtreeparser.h"
#include "stream/stream.h"
#include "libmpdemux/demuxer.h"
#include "mp_msg.h"
extern play_tree_t*
asx_parser_build_tree(char* buffer, int ref);
#define BUF_STEP 1024
#define WHITES " \n\r\t"
static void
strstrip(char* str) {
char* i;
if (str==NULL)
return;
for(i = str ; i[0] != '\0' && strchr(WHITES,i[0]) != NULL; i++)
/* NOTHING */;
if(i[0] != '\0') {
memmove(str,i,strlen(i) + 1);
for(i = str + strlen(str) - 1 ; strchr(WHITES,i[0]) != NULL; i--)
/* NOTHING */;
i[1] = '\0';
} else
str[0] = '\0';
}
static char*
play_tree_parser_get_line(play_tree_parser_t* p) {
char *end,*line_end;
int r,resize = 0;
if(p->buffer == NULL) {
p->buffer = malloc(BUF_STEP);
p->buffer_size = BUF_STEP;
p->buffer[0] = 0;
p->iter = p->buffer;
}
if(p->stream->eof && (p->buffer_end == 0 || p->iter[0] == '\0'))
return NULL;
assert(p->buffer_end < p->buffer_size);
assert(!p->buffer[p->buffer_end]);
while(1) {
if(resize) {
r = p->iter - p->buffer;
p->buffer = (char*)realloc(p->buffer,p->buffer_size+BUF_STEP);
p->iter = p->buffer + r;
p->buffer_size += BUF_STEP;
resize = 0;
}
if(p->buffer_size - p->buffer_end > 1 && ! p->stream->eof) {
r = stream_read(p->stream,p->buffer + p->buffer_end,p->buffer_size - p->buffer_end - 1);
if(r > 0) {
p->buffer_end += r;
assert(p->buffer_end < p->buffer_size);
p->buffer[p->buffer_end] = '\0';
while(strlen(p->buffer + p->buffer_end - r) != r)
p->buffer[p->buffer_end - r + strlen(p->buffer + p->buffer_end - r)] = '\n';
}
assert(!p->buffer[p->buffer_end]);
}
end = strchr(p->iter,'\n');
if(!end) {
if(p->stream->eof) {
end = p->buffer + p->buffer_end;
break;
}
resize = 1;
continue;
}
break;
}
line_end = (end > p->iter && *(end-1) == '\r') ? end-1 : end;
if(line_end - p->iter >= 0)
p->line = (char*)realloc(p->line,line_end - p->iter+1);
else
return NULL;
if(line_end - p->iter > 0)
strncpy(p->line,p->iter,line_end - p->iter);
p->line[line_end - p->iter] = '\0';
if(end[0] != '\0')
end++;
if(!p->keep) {
if(end[0] != '\0') {
p->buffer_end -= end-p->iter;
memmove(p->buffer,end,p->buffer_end);
} else
p->buffer_end = 0;
p->buffer[p->buffer_end] = '\0';
p->iter = p->buffer;
} else
p->iter = end;
return p->line;
}
static void
play_tree_parser_reset(play_tree_parser_t* p) {
p->iter = p->buffer;
}
static void
play_tree_parser_stop_keeping(play_tree_parser_t* p) {
p->keep = 0;
if(p->iter && p->iter != p->buffer) {
p->buffer_end -= p->iter -p->buffer;
if(p->buffer_end)
memmove(p->buffer,p->iter,p->buffer_end);
p->buffer[p->buffer_end] = 0;
p->iter = p->buffer;
}
}
static play_tree_t*
parse_asx(play_tree_parser_t* p) {
int comments = 0,get_line = 1;
char* line = NULL;
mp_msg(MSGT_PLAYTREE,MSGL_V,"Trying asx...\n");
while(1) {
if(get_line) {
line = play_tree_parser_get_line(p);
if(!line)
return NULL;
strstrip(line);
if(line[0] == '\0')
continue;
}
if(!comments) {
if(line[0] != '<') {
mp_msg(MSGT_PLAYTREE,MSGL_DBG2,"First char isn't '<' but '%c'\n",line[0]);
mp_msg(MSGT_PLAYTREE,MSGL_DBG3,"Buffer = [%s]\n",p->buffer);
return NULL;
} else if(strncmp(line,"<!--",4) == 0) { // Comments
comments = 1;
line += 4;
if(line[0] != '\0' && strlen(line) > 0)
get_line = 0;
} else if(strncasecmp(line,"<ASX",4) == 0) // We got an asx element
break;
else // We don't get an asx
return NULL;
} else { // Comments
char* c;
c = strchr(line,'-');
if(c) {
if (strncmp(c,"--!>",4) == 0) { // End of comments
comments = 0;
line = c+4;
if(line[0] != '\0') // There is some more data on this line : keep it
get_line = 0;
} else {
line = c+1; // Jump the -
if(line[0] != '\0') // Some more data
get_line = 0;
else // End of line
get_line = 1;
}
} else // No - on this line (or rest of line) : get next one
get_line = 1;
}
}
mp_msg(MSGT_PLAYTREE,MSGL_V,"Detected asx format\n");
// We have an asx : load it in memory and parse
while((line = play_tree_parser_get_line(p)) != NULL)
/* NOTHING */;
mp_msg(MSGT_PLAYTREE,MSGL_DBG3,"Parsing asx file: [%s]\n",p->buffer);
return asx_parser_build_tree(p->buffer,p->deep);
}
static char*
pls_entry_get_value(char* line) {
char* i;
i = strchr(line,'=');
if(!i || i[1] == '\0')
return NULL;
else
return i+1;
}
typedef struct pls_entry {
char* file;
char* title;
char* length;
} pls_entry_t;
static int
pls_read_entry(char* line,pls_entry_t** _e,int* _max_entry,char** val) {
int num,max_entry = (*_max_entry);
pls_entry_t* e = (*_e);
char* v;
v = pls_entry_get_value(line);
if(!v) {
mp_msg(MSGT_PLAYTREE,MSGL_ERR,"No value in entry %s\n",line);
return 0;
}
num = atoi(line);
if(num < 0) {
num = max_entry+1;
mp_msg(MSGT_PLAYTREE,MSGL_WARN,"No entry index in entry %s\nAssuming %d\n",line,num);
}
if(num > max_entry) {
e = (pls_entry_t*)realloc(e,num*sizeof(pls_entry_t));
memset(&e[max_entry],0,(num-max_entry)*sizeof(pls_entry_t));
max_entry = num;
}
(*_e) = e;
(*_max_entry) = max_entry;
(*val) = v;
return num;
}
static play_tree_t*
parse_pls(play_tree_parser_t* p) {
char *line,*v;
pls_entry_t* entries = NULL;
int n_entries = 0,max_entry=0,num;
play_tree_t *list = NULL, *entry = NULL, *last_entry = NULL;
mp_msg(MSGT_PLAYTREE,MSGL_V,"Trying Winamp playlist...\n");
while((line = play_tree_parser_get_line(p))) {
strstrip(line);
if(strlen(line))
break;
}
if (!line)
return NULL;
if(strcasecmp(line,"[playlist]"))
return NULL;
mp_msg(MSGT_PLAYTREE,MSGL_V,"Detected Winamp playlist format\n");
play_tree_parser_stop_keeping(p);
line = play_tree_parser_get_line(p);
if(!line)
return NULL;
strstrip(line);
if(strncasecmp(line,"NumberOfEntries",15) == 0) {
v = pls_entry_get_value(line);
n_entries = atoi(v);
if(n_entries < 0)
mp_msg(MSGT_PLAYTREE,MSGL_DBG2,"Invalid number of entries: very funny!!!\n");
else
mp_msg(MSGT_PLAYTREE,MSGL_DBG2,"Playlist claims to have %d entries. Let's see.\n",n_entries);
line = play_tree_parser_get_line(p);
}
while(line) {
strstrip(line);
if(line[0] == '\0') {
line = play_tree_parser_get_line(p);
continue;
}
if(strncasecmp(line,"File",4) == 0) {
num = pls_read_entry(line+4,&entries,&max_entry,&v);
if(num < 0)
mp_msg(MSGT_PLAYTREE,MSGL_ERR,"No value in entry %s\n",line);
else
entries[num-1].file = strdup(v);
} else if(strncasecmp(line,"Title",5) == 0) {
num = pls_read_entry(line+5,&entries,&max_entry,&v);
if(num < 0)
mp_msg(MSGT_PLAYTREE,MSGL_ERR,"No value in entry %s\n",line);
else
entries[num-1].title = strdup(v);
} else if(strncasecmp(line,"Length",6) == 0) {
num = pls_read_entry(line+6,&entries,&max_entry,&v);
if(num < 0)
mp_msg(MSGT_PLAYTREE,MSGL_ERR,"No value in entry %s\n",line);
else
entries[num-1].length = strdup(v);
} else
mp_msg(MSGT_PLAYTREE,MSGL_WARN,"Unknown entry type %s\n",line);
line = play_tree_parser_get_line(p);
}
for(num = 0; num < max_entry ; num++) {
if(entries[num].file == NULL)
mp_msg(MSGT_PLAYTREE,MSGL_ERR,"Entry %d don't have a file !!!!\n",num+1);
else {
mp_msg(MSGT_PLAYTREE,MSGL_DBG2,"Adding entry %s\n",entries[num].file);
entry = play_tree_new();
play_tree_add_file(entry,entries[num].file);
free(entries[num].file);
if(list)
play_tree_append_entry(last_entry,entry);
else
list = entry;
last_entry = entry;
}
if(entries[num].title) {
// When we have info in playtree we add this info
free(entries[num].title);
}
if(entries[num].length) {
// When we have info in playtree we add this info
free(entries[num].length);
}
}
free(entries);
entry = play_tree_new();
play_tree_set_child(entry,list);
return entry;
}
/*
Reference Ini-Format: Each entry is assumed a reference
*/
static play_tree_t*
parse_ref_ini(play_tree_parser_t* p) {
char *line,*v;
play_tree_t *list = NULL, *entry = NULL, *last_entry = NULL;
mp_msg(MSGT_PLAYTREE,MSGL_V,"Trying reference-ini playlist...\n");
if (!(line = play_tree_parser_get_line(p)))
return NULL;
strstrip(line);
if(strcasecmp(line,"[Reference]"))
return NULL;
mp_msg(MSGT_PLAYTREE,MSGL_V,"Detected reference-ini playlist format\n");
play_tree_parser_stop_keeping(p);
line = play_tree_parser_get_line(p);
if(!line)
return NULL;
while(line) {
strstrip(line);
if(strncasecmp(line,"Ref",3) == 0) {
v = pls_entry_get_value(line+3);
if(!v)
mp_msg(MSGT_PLAYTREE,MSGL_ERR,"No value in entry %s\n",line);
else
{
mp_msg(MSGT_PLAYTREE,MSGL_DBG2,"Adding entry %s\n",v);
entry = play_tree_new();
play_tree_add_file(entry,v);
if(list)
play_tree_append_entry(last_entry,entry);
else
list = entry;
last_entry = entry;
}
}
line = play_tree_parser_get_line(p);
}
if(!list) return NULL;
entry = play_tree_new();
play_tree_set_child(entry,list);
return entry;
}
static play_tree_t*
parse_m3u(play_tree_parser_t* p) {
char* line;
play_tree_t *list = NULL, *entry = NULL, *last_entry = NULL;
mp_msg(MSGT_PLAYTREE,MSGL_V,"Trying extended m3u playlist...\n");
if (!(line = play_tree_parser_get_line(p)))
return NULL;
strstrip(line);
if(strcasecmp(line,"#EXTM3U"))
return NULL;
mp_msg(MSGT_PLAYTREE,MSGL_V,"Detected extended m3u playlist format\n");
play_tree_parser_stop_keeping(p);
while((line = play_tree_parser_get_line(p)) != NULL) {
strstrip(line);
if(line[0] == '\0')
continue;
/* EXTM3U files contain such lines:
* #EXTINF:<seconds>, <title>
* followed by a line with the filename
* for now we have no place to put that
* so we just skip that extra-info ::atmos
*/
if(line[0] == '#') {
#if 0 /* code functional */
if(strncasecmp(line,"#EXTINF:",8) == 0) {
mp_msg(MSGT_PLAYTREE,MSGL_INFO,"[M3U] Duration: %dsec Title: %s\n",
strtol(line+8,&line,10), line+2);
}
#endif
continue;
}
entry = play_tree_new();
play_tree_add_file(entry,line);
if(!list)
list = entry;
else
play_tree_append_entry(last_entry,entry);
last_entry = entry;
}
if(!list) return NULL;
entry = play_tree_new();
play_tree_set_child(entry,list);
return entry;
}
static play_tree_t*
parse_smil(play_tree_parser_t* p) {
int entrymode=0;
char* line,source[512],*pos,*s_start,*s_end,*src_line;
play_tree_t *list = NULL, *entry = NULL, *last_entry = NULL;
int is_rmsmil = 0;
unsigned int npkt, ttlpkt;
mp_msg(MSGT_PLAYTREE,MSGL_V,"Trying smil playlist...\n");
// Check if smil
while((line = play_tree_parser_get_line(p)) != NULL) {
strstrip(line);
if(line[0] == '\0') // Ignore empties
continue;
if (strncasecmp(line,"<?xml",5)==0) // smil in xml
continue;
if (strncasecmp(line,"<!DOCTYPE smil",13)==0) // smil in xml
continue;
if (strncasecmp(line,"<smil",5)==0 || strncasecmp(line,"<?wpl",5)==0 ||
strncasecmp(line,"(smil-document",14)==0)
break; // smil header found
else
return NULL; //line not smil exit
}
if (!line) return NULL;
mp_msg(MSGT_PLAYTREE,MSGL_V,"Detected smil playlist format\n");
play_tree_parser_stop_keeping(p);
if (strncasecmp(line,"(smil-document",14)==0) {
mp_msg(MSGT_PLAYTREE,MSGL_V,"Special smil-over-realrtsp playlist header\n");
is_rmsmil = 1;
if (sscanf(line, "(smil-document (ver 1.0)(npkt %u)(ttlpkt %u", &npkt, &ttlpkt) != 2) {
mp_msg(MSGT_PLAYTREE,MSGL_WARN,"smil-over-realrtsp: header parsing failure, assuming single packet.\n");
npkt = ttlpkt = 1;
}
if (ttlpkt == 0 || npkt > ttlpkt) {
mp_msg(MSGT_PLAYTREE,MSGL_WARN,"smil-over-realrtsp: bad packet counters (npkk = %u, ttlpkt = %u), assuming single packet.\n",
npkt, ttlpkt);
npkt = ttlpkt = 1;
}
}
//Get entries from smil
src_line = line;
line = NULL;
do {
strstrip(src_line);
if (line) {
free(line);
line = NULL;
}
/* If we're parsing smil over realrtsp and this is not the last packet and
* this is the last line in the packet (terminating with ") ) we must get
* the next line, strip the header, and concatenate it to the current line.
*/
if (is_rmsmil && npkt != ttlpkt && strstr(src_line,"\")")) {
char *payload;
line = strdup(src_line);
if(!(src_line = play_tree_parser_get_line(p))) {
mp_msg(MSGT_PLAYTREE,MSGL_WARN,"smil-over-realrtsp: can't get line from packet %u/%u.\n", npkt, ttlpkt);
break;
}
strstrip(src_line);
// Skip header, packet starts after "
if(!(payload = strchr(src_line,'\"'))) {
mp_msg(MSGT_PLAYTREE,MSGL_WARN,"smil-over-realrtsp: can't find start of packet, using complete line.\n");
payload = src_line;
} else
payload++;
// Skip ") at the end of the last line from the current packet
line[strlen(line)-2] = 0;
line = realloc(line, strlen(line)+strlen(payload)+1);
strcat (line, payload);
npkt++;
} else
line = strdup(src_line);
/* Unescape \" to " for smil-over-rtsp */
if (is_rmsmil && line[0] != '\0') {
int i, j;
for (i = 0; i < strlen(line); i++)
if (line[i] == '\\' && line[i+1] == '"')
for (j = i; line[j]; j++)
line[j] = line[j+1];
}
pos = line;
while (pos) {
if (!entrymode) { // all entries filled so far
while ((pos=strchr(pos, '<'))) {
if (strncasecmp(pos,"<video",6)==0 || strncasecmp(pos,"<audio",6)==0 || strncasecmp(pos,"<media",6)==0) {
entrymode=1;
break; // Got a valid tag, exit '<' search loop
}
pos++;
}
}
if (entrymode) { //Entry found but not yet filled
pos = strstr(pos,"src="); // Is source present on this line
if (pos != NULL) {
entrymode=0;
if (pos[4] != '"' && pos[4] != '\'') {
mp_msg(MSGT_PLAYTREE,MSGL_V,"Unknown delimiter %c in source line %s\n", pos[4], line);
break;
}
s_start=pos+5;
s_end=strchr(s_start,pos[4]);
if (s_end == NULL) {
mp_msg(MSGT_PLAYTREE,MSGL_V,"Error parsing this source line %s\n",line);
break;
}
if (s_end-s_start> 511) {
mp_msg(MSGT_PLAYTREE,MSGL_V,"Cannot store such a large source %s\n",line);
break;
}
strncpy(source,s_start,s_end-s_start);
source[(s_end-s_start)]='\0'; // Null terminate
entry = play_tree_new();
play_tree_add_file(entry,source);
if(!list) //Insert new entry
list = entry;
else
play_tree_append_entry(last_entry,entry);
last_entry = entry;
pos = s_end;
}
}
}
} while((src_line = play_tree_parser_get_line(p)) != NULL);
if (line)
free(line);
if(!list) return NULL; // Nothing found
entry = play_tree_new();
play_tree_set_child(entry,list);
return entry;
}
static play_tree_t*
embedded_playlist_parse(char *line) {
int f=DEMUXER_TYPE_PLAYLIST;
stream_t* stream;
play_tree_parser_t* ptp;
play_tree_t* entry;
// Get stream opened to link
stream=open_stream(line,0,&f);
if(!stream) {
mp_msg(MSGT_PLAYTREE,MSGL_WARN,"Can't open playlist %s\n",line);
return NULL;
}
//add new playtree
mp_msg(MSGT_PLAYTREE,MSGL_V,"Adding playlist %s to element entryref\n",line);
ptp = play_tree_parser_new(stream,1);
entry = play_tree_parser_get_play_tree(ptp, 1);
play_tree_parser_free(ptp);
free_stream(stream);
return entry;
}
static play_tree_t*
parse_textplain(play_tree_parser_t* p) {
char* line;
char *c;
int embedded;
play_tree_t *list = NULL, *entry = NULL, *last_entry = NULL;
mp_msg(MSGT_PLAYTREE,MSGL_V,"Trying plaintext playlist...\n");
play_tree_parser_stop_keeping(p);
while((line = play_tree_parser_get_line(p)) != NULL) {
strstrip(line);
if(line[0] == '\0' || line[0] == '#' || (line[0] == '/' && line[1] == '/'))
continue;
//Special check for embedded smil or ram reference in file
embedded = 0;
if (strlen(line) > 5)
for(c = line; c[0]; c++ )
if ( ((c[0] == '.') && //start with . and next have smil with optional ? or &
(tolower(c[1]) == 's') && (tolower(c[2])== 'm') &&
(tolower(c[3]) == 'i') && (tolower(c[4]) == 'l') &&
(!c[5] || c[5] == '?' || c[5] == '&')) || // or
((c[0] == '.') && // start with . and next have smi or ram with optional ? or &
( ((tolower(c[1]) == 's') && (tolower(c[2])== 'm') && (tolower(c[3]) == 'i')) ||
((tolower(c[1]) == 'r') && (tolower(c[2])== 'a') && (tolower(c[3]) == 'm')) )
&& (!c[4] || c[4] == '?' || c[4] == '&')) ){
entry=embedded_playlist_parse(line);
embedded = 1;
break;
}
if (!embedded) { //regular file link
entry = play_tree_new();
play_tree_add_file(entry,line);
}
if (entry != NULL) {
if(!list)
list = entry;
else
play_tree_append_entry(last_entry,entry);
last_entry = entry;
}
}
if(!list) return NULL;
entry = play_tree_new();
play_tree_set_child(entry,list);
return entry;
}
play_tree_t*
parse_playtree(stream_t *stream, int forced) {
play_tree_parser_t* p;
play_tree_t* ret;
#ifdef MP_DEBUG
assert(stream != NULL);
#endif
p = play_tree_parser_new(stream,0);
if(!p)
return NULL;
ret = play_tree_parser_get_play_tree(p, forced);
play_tree_parser_free(p);
return ret;
}
static void
play_tree_add_basepath(play_tree_t* pt, char* bp) {
int i,bl = strlen(bp),fl;
if(pt->child) {
play_tree_t* i;
for(i = pt->child ; i != NULL ; i = i->next)
play_tree_add_basepath(i,bp);
return;
}
if(!pt->files)
return;
for(i = 0 ; pt->files[i] != NULL ; i++) {
fl = strlen(pt->files[i]);
// if we find a full unix path, url:// or X:\ at the beginning,
// don't mangle it.
if(fl <= 0 || strstr(pt->files[i],"://") || (strstr(pt->files[i],":\\") == pt->files[i] + 1) || (pt->files[i][0] == '/') )
continue;
// if the path begins with \ then prepend drive letter to it.
if (pt->files[i][0] == '\\') {
if (pt->files[i][1] == '\\')
continue;
pt->files[i] = (char*)realloc(pt->files[i],2+fl+1);
memmove(pt->files[i] + 2,pt->files[i],fl+1);
memcpy(pt->files[i],bp,2);
continue;
}
pt->files[i] = (char*)realloc(pt->files[i],bl+fl+1);
memmove(pt->files[i] + bl,pt->files[i],fl+1);
memcpy(pt->files[i],bp,bl);
}
}
// Wrapper for play_tree_add_basepath (add base path from file)
void play_tree_add_bpf(play_tree_t* pt, char* filename)
{
char *ls, *file;
if (pt && filename)
{
file = strdup(filename);
if (file)
{
ls = strrchr(file,'/');
if(!ls) ls = strrchr(file,'\\');
if(ls) {
ls[1] = '\0';
play_tree_add_basepath(pt,file);
}
free(file);
}
}
}
play_tree_t*
parse_playlist_file(char* file) {
stream_t *stream;
play_tree_t* ret;
int f=DEMUXER_TYPE_PLAYLIST;
stream = open_stream(file,0,&f);
if(!stream) {
mp_msg(MSGT_PLAYTREE,MSGL_ERR,"Error while opening playlist file %s: %s\n",file,strerror(errno));
return NULL;
}
mp_msg(MSGT_PLAYTREE,MSGL_V,"Parsing playlist file %s...\n",file);
ret = parse_playtree(stream,1);
free_stream(stream);
play_tree_add_bpf(ret, file);
return ret;
}
play_tree_parser_t*
play_tree_parser_new(stream_t* stream,int deep) {
play_tree_parser_t* p;
p = calloc(1,sizeof(play_tree_parser_t));
if(!p)
return NULL;
p->stream = stream;
p->deep = deep;
p->keep = 1;
return p;
}
void
play_tree_parser_free(play_tree_parser_t* p) {
#ifdef MP_DEBUG
assert(p != NULL);
#endif
if(p->buffer) free(p->buffer);
if(p->line) free(p->line);
free(p);
}
play_tree_t*
play_tree_parser_get_play_tree(play_tree_parser_t* p, int forced) {
play_tree_t* tree = NULL;
#ifdef MP_DEBUG
assert(p != NULL);
#endif
while(play_tree_parser_get_line(p) != NULL) {
play_tree_parser_reset(p);
tree = parse_asx(p);
if(tree) break;
play_tree_parser_reset(p);
tree = parse_pls(p);
if(tree) break;
play_tree_parser_reset(p);
tree = parse_m3u(p);
if(tree) break;
play_tree_parser_reset(p);
tree = parse_ref_ini(p);
if(tree) break;
play_tree_parser_reset(p);
tree = parse_smil(p);
if(tree) break;
play_tree_parser_reset(p);
// Here come the others formats ( textplain must stay the last one )
if (forced)
{
tree = parse_textplain(p);
if(tree) break;
}
break;
}
if(tree)
mp_msg(MSGT_PLAYTREE,MSGL_V,"Playlist successfully parsed\n");
else
mp_msg(MSGT_PLAYTREE,((forced==1)?MSGL_ERR:MSGL_V),"Error while parsing playlist\n");
if(tree)
tree = play_tree_cleanup(tree);
if(!tree) mp_msg(MSGT_PLAYTREE,((forced==1)?MSGL_WARN:MSGL_V),"Warning: empty playlist\n");
return tree;
}