/*
* Copyright (C) 2003-2015 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 "Format.hxx"
#include "Tag.hxx"
#include "util/format.h"
#include "util/StringUtil.hxx"
#include <algorithm>
#include <string.h>
struct FormatTagContext {
const Tag &tag;
char buffer[256];
explicit FormatTagContext(const Tag &_tag):tag(_tag) {}
};
/**
* Is this a character unsafe to use in a path name segment?
*/
static constexpr bool
IsUnsafeChar(char ch)
{
return
/* disallow characters illegal in file names on
Windows (Linux allows almost anything) */
ch == '\\' || ch == '/' || ch == ':' || ch == '*' ||
ch == '?' || ch == '<' || ch == '>' || ch == '|' ||
/* allow space, but disallow all other whitespace */
(unsigned char)ch < 0x20;
}
gcc_pure
static bool
HasUnsafeChar(const char *s)
{
for (; *s; ++s)
if (IsUnsafeChar(*s))
return true;
return false;
}
static const char *
SanitizeString(const char *s, char *buffer, size_t buffer_size)
{
/* skip leading dots to avoid generating "../" sequences */
while (*s == '.')
++s;
if (!HasUnsafeChar(s))
return s;
char *end = CopyString(buffer, s, buffer_size);
std::replace_if(buffer, end, IsUnsafeChar, ' ');
return buffer;
}
gcc_pure gcc_nonnull_all
static const char *
TagGetter(const void *object, const char *name)
{
const auto &_ctx = *(const FormatTagContext *)object;
auto &ctx = const_cast<FormatTagContext &>(_ctx);
const Tag &tag = ctx.tag;
TagType tag_type = tag_name_parse_i(name);
if (tag_type == TAG_NUM_OF_ITEM_TYPES)
/* unknown tag name */
return nullptr;
const char *value = tag.GetValue(tag_type);
if (value == nullptr)
/* known tag name, but not present in this object */
value = "";
// TODO: handle multiple tag values
return SanitizeString(value, ctx.buffer, sizeof(ctx.buffer));
}
char *
FormatTag(const Tag &tag, const char *format)
{
FormatTagContext ctx(tag);
return format_object(format, &ctx, TagGetter);
}
