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/*
* SCAN Name Abstraction
* (C) 2008-2009,2015 Jack Lloyd
*
* Botan is released under the Simplified BSD License (see license.txt)
*/
#include <botan/scan_name.h>
#include <botan/parsing.h>
#include <botan/exceptn.h>
namespace Botan {
namespace {
std::string make_arg(const std::vector<std::pair<size_t, std::string>>& name, size_t start)
{
std::string output = name[start].second;
size_t level = name[start].first;
size_t paren_depth = 0;
for(size_t i = start + 1; i != name.size(); ++i)
{
if(name[i].first <= name[start].first)
break;
if(name[i].first > level)
{
output += "(" + name[i].second;
++paren_depth;
}
else if(name[i].first < level)
{
for (size_t j = name[i].first; j < level; j++) {
output += ")";
--paren_depth;
}
output += "," + name[i].second;
}
else
{
if(output[output.size() - 1] != '(')
output += ",";
output += name[i].second;
}
level = name[i].first;
}
for(size_t i = 0; i != paren_depth; ++i)
output += ")";
return output;
}
}
SCAN_Name::SCAN_Name(const char* algo_spec) : SCAN_Name(std::string(algo_spec))
{
}
SCAN_Name::SCAN_Name(std::string algo_spec) : m_orig_algo_spec(algo_spec), m_alg_name(), m_args(), m_mode_info()
{
if(algo_spec.size() == 0)
throw Invalid_Argument("Expected algorithm name, got empty string");
std::vector<std::pair<size_t, std::string>> name;
size_t level = 0;
std::pair<size_t, std::string> accum = std::make_pair(level, "");
const std::string decoding_error = "Bad SCAN name '" + algo_spec + "': ";
for(size_t i = 0; i != algo_spec.size(); ++i)
{
char c = algo_spec[i];
if(c == '/' || c == ',' || c == '(' || c == ')')
{
if(c == '(')
++level;
else if(c == ')')
{
if(level == 0)
throw Decoding_Error(decoding_error + "Mismatched parens");
--level;
}
if(c == '/' && level > 0)
accum.second.push_back(c);
else
{
if(accum.second != "")
name.push_back(accum);
accum = std::make_pair(level, "");
}
}
else
accum.second.push_back(c);
}
if(accum.second != "")
name.push_back(accum);
if(level != 0)
throw Decoding_Error(decoding_error + "Missing close paren");
if(name.size() == 0)
throw Decoding_Error(decoding_error + "Empty name");
m_alg_name = name[0].second;
bool in_modes = false;
for(size_t i = 1; i != name.size(); ++i)
{
if(name[i].first == 0)
{
m_mode_info.push_back(make_arg(name, i));
in_modes = true;
}
else if(name[i].first == 1 && !in_modes)
m_args.push_back(make_arg(name, i));
}
}
std::string SCAN_Name::arg(size_t i) const
{
if(i >= arg_count())
throw Invalid_Argument("SCAN_Name::arg " + std::to_string(i) +
" out of range for '" + to_string() + "'");
return m_args[i];
}
std::string SCAN_Name::arg(size_t i, const std::string& def_value) const
{
if(i >= arg_count())
return def_value;
return m_args[i];
}
size_t SCAN_Name::arg_as_integer(size_t i, size_t def_value) const
{
if(i >= arg_count())
return def_value;
return to_u32bit(m_args[i]);
}
}