mpd/src/util/UriUtil.cxx
2022-04-26 20:31:56 +02:00

149 lines
3.4 KiB
C++

/*
* Copyright 2008-2019 Max Kellermann <max.kellermann@gmail.com>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* FOUNDATION OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "UriUtil.hxx"
#include "ASCII.hxx"
#include "SplitString.hxx"
#include <array>
#include <cassert>
#include <cstring>
#include <string_view>
static const char *
verify_uri_segment(const char *p) noexcept
{
unsigned dots = 0;
while (*p == '.') {
++p;
++dots;
}
if (dots <= 2 && (*p == 0 || *p == '/'))
return nullptr;
const char *q = std::strchr(p + 1, '/');
return q != nullptr ? q : "";
}
bool
uri_safe_local(const char *uri) noexcept
{
while (true) {
uri = verify_uri_segment(uri);
if (uri == nullptr)
return false;
if (*uri == 0)
return true;
assert(*uri == '/');
++uri;
}
}
[[gnu::pure]]
static const char *
SkipUriScheme(const char *uri) noexcept
{
static constexpr auto schemes = std::array {
"http://", "https://",
"ftp://",
"smb://",
};
for (auto scheme : schemes) {
auto result = StringAfterPrefixCaseASCII(uri, scheme);
if (result != nullptr)
return result;
}
return nullptr;
}
std::string
uri_remove_auth(const char *uri) noexcept
{
const char *auth = SkipUriScheme(uri);
if (auth == nullptr)
/* unrecognized URI */
return {};
const char *slash = std::strchr(auth, '/');
if (slash == nullptr)
slash = auth + strlen(auth);
auto at = (const char *)std::memchr(auth, '@', slash - auth);
if (at == nullptr)
/* no auth info present, do nothing */
return {};
/* duplicate the full URI and then delete the auth
information */
std::string result(uri);
result.erase(auth - uri, at + 1 - auth);
return result;
}
std::string
uri_squash_dot_segments(const char *uri) noexcept
{
std::forward_list<std::string_view> path = SplitString(std::string_view(uri), '/');
path.remove_if([](const std::string_view &seg) { return seg == "."; });
path.reverse();
std::string result;
int segskips = 0;
auto it = path.begin();
while (it != path.end()) {
if (*it == "..") {
segskips++;
it++;
continue;
} else if (segskips != 0) {
segskips--;
it++;
continue;
}
result.insert(0, *it);
if (it != path.begin()) {
result.insert(it->length(), "/");
}
it++;
}
return result;
}