owntone-server/src/smartpl_query.c

152 lines
3.9 KiB
C

/*
* Copyright (C) 2021-2022 Espen Jürgensen <espenjurgensen@gmail.com>
*
* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <limits.h>
#include <sys/param.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <errno.h>
#include "smartpl_query.h"
#include "parsers/smartpl_parser.h"
#include "logger.h"
#include "misc.h"
#define SMARTPL_SIZE_MAX 8192
int
smartpl_query_parse_file(struct smartpl *smartpl, const char *file)
{
char *expression = NULL;
size_t size;
size_t got;
int ret;
FILE *f;
f = fopen(file, "rb");
if (!f)
{
DPRINTF(E_LOG, L_SCAN, "Could not open smart playlist '%s'\n", file);
goto error;
}
fseek(f, 0, SEEK_END);
size = ftell(f);
if (size <= 0 || size > SMARTPL_SIZE_MAX)
{
DPRINTF(E_LOG, L_SCAN, "Smart playlist '%s' is zero bytes or too large (max size is %d)\n", file, SMARTPL_SIZE_MAX);
goto error;
}
fseek(f, 0, SEEK_SET);
CHECK_NULL(L_SCAN, expression = calloc(1, size + 1));
got = fread(expression, 1, size, f);
if (got != size)
{
DPRINTF(E_LOG, L_SCAN, "Unknown error reading smart playlist '%s'\n", file);
goto error;
}
fclose(f);
ret = smartpl_query_parse_string(smartpl, expression);
free(expression);
return ret;
error:
free(expression);
if (f)
fclose(f);
return -1;
}
int
smartpl_query_parse_string(struct smartpl *smartpl, const char *expression)
{
struct smartpl_result result;
if (!expression)
{
DPRINTF(E_WARN, L_SCAN, "Parse smartpl query input is null\n");
return -1;
}
DPRINTF(E_SPAM, L_SCAN, "Parse smartpl query input '%s'\n", expression);
if (smartpl_lex_parse(&result, expression) != 0)
{
DPRINTF(E_LOG, L_SCAN, "Could not parse '%s': %s\n", expression, result.errmsg);
return -1;
}
if (result.title[0] == '\0' || !result.where)
{
DPRINTF(E_LOG, L_SCAN, "Missing title or filter when parsing '%s'\n", expression);
return -1;
}
free_smartpl(smartpl, 1);
// Note the fields returned by the smartpl parser will not be prefixed with
// "f." (unlike the daap parser results and most other queries). The reason is
// that the smartpl syntax allows the user to request ordering by a calculated
// field in a group query, and calculated fields are not in the "f" namespace.
// An example of this happening is if the JSON API search is called with
// type=album and the smartpl expression has "order+by+time_played+desc".
smartpl->title = strdup(result.title);
smartpl->query_where = strdup(result.where);
smartpl->having = safe_strdup(result.having);
smartpl->order = safe_strdup(result.order);
smartpl->limit = result.limit;
DPRINTF(E_SPAM, L_SCAN, "Parse smartpl query output '%s': WHERE %s HAVING %s ORDER BY %s LIMIT %d\n",
smartpl->title, smartpl->query_where, smartpl->having, smartpl->order, smartpl->limit);
return 0;
}
void
free_smartpl(struct smartpl *smartpl, int content_only)
{
if (!smartpl)
return;
free(smartpl->title);
free(smartpl->query_where);
free(smartpl->having);
free(smartpl->order);
if (!content_only)
free(smartpl);
else
memset(smartpl, 0, sizeof(struct smartpl));
}