lldb/source/Interpreter/CommandAlias.cpp

//===-- CommandAlias.cpp ------------------------------------------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

#include "lldb/Interpreter/CommandAlias.h"

#include "llvm/Support/ErrorHandling.h"

#include "lldb/Core/StreamString.h"
#include "lldb/Interpreter/CommandInterpreter.h"
#include "lldb/Interpreter/CommandObject.h"
#include "lldb/Interpreter/CommandReturnObject.h"
#include "lldb/Interpreter/Options.h"

using namespace lldb;
using namespace lldb_private;

static bool
ProcessAliasOptionsArgs (lldb::CommandObjectSP &cmd_obj_sp,
                         const char *options_args,
                         OptionArgVectorSP &option_arg_vector_sp)
{
    bool success = true;
    OptionArgVector *option_arg_vector = option_arg_vector_sp.get();
    
    if (!options_args || (strlen (options_args) < 1))
        return true;
    
    std::string options_string (options_args);
    Args args (options_args);
    CommandReturnObject result;
    // Check to see if the command being aliased can take any command options.
    Options *options = cmd_obj_sp->GetOptions ();
    if (options)
    {
        // See if any options were specified as part of the alias;  if so, handle them appropriately.
        ExecutionContext exe_ctx =
            cmd_obj_sp->GetCommandInterpreter().GetExecutionContext();
        options->NotifyOptionParsingStarting(&exe_ctx);
        args.Unshift ("dummy_arg");
        args.ParseAliasOptions (*options, result, option_arg_vector, options_string);
        args.Shift ();
        if (result.Succeeded())
            options->VerifyPartialOptions (result);
        if (!result.Succeeded() && result.GetStatus() != lldb::eReturnStatusStarted)
        {
            result.AppendError ("Unable to create requested alias.\n");
            return false;
        }
    }
    
    if (!options_string.empty())
    {
        if (cmd_obj_sp->WantsRawCommandString ())
            option_arg_vector->push_back (OptionArgPair ("<argument>",
                                                         OptionArgValue (-1,
                                                                         options_string)));
        else
        {
            const size_t argc = args.GetArgumentCount();
            for (size_t i = 0; i < argc; ++i)
                if (strcmp (args.GetArgumentAtIndex (i), "") != 0)
                    option_arg_vector->push_back
                    (OptionArgPair ("<argument>",
                                    OptionArgValue (-1,
                                                    std::string (args.GetArgumentAtIndex (i)))));
        }
    }
    
    return success;
}

CommandAlias::CommandAlias (CommandInterpreter &interpreter,
                            lldb::CommandObjectSP cmd_sp,
                            const char *options_args,
                            const char *name,
                            const char *help,
                            const char *syntax,
                            uint32_t flags) :
    CommandObject(interpreter,
                  name,
                  help,
                  syntax,
                  flags),
m_underlying_command_sp(),
m_option_string(options_args ? options_args : ""),
m_option_args_sp(new OptionArgVector),
m_is_dashdash_alias(eLazyBoolCalculate),
m_did_set_help(false),
m_did_set_help_long(false)
{
    if (ProcessAliasOptionsArgs(cmd_sp, options_args, m_option_args_sp))
    {
        m_underlying_command_sp = cmd_sp;
        for (int i = 0;
             auto cmd_entry = m_underlying_command_sp->GetArgumentEntryAtIndex(i);
             i++)
        {
            m_arguments.push_back(*cmd_entry);
        }
        if (!help || !help[0])
        {
            StreamString sstr;
            StreamString translation_and_help;
            GetAliasExpansion(sstr);
            
            translation_and_help.Printf ("(%s)  %s", sstr.GetData(), GetUnderlyingCommand()->GetHelp());
            SetHelp(translation_and_help.GetData());
        }
    }
}

bool
CommandAlias::WantsRawCommandString()
{
    if (IsValid())
        return m_underlying_command_sp->WantsRawCommandString();
    return false;
}

bool
CommandAlias::WantsCompletion()
{
    if (IsValid())
        return m_underlying_command_sp->WantsCompletion();
    return false;
}

int
CommandAlias::HandleCompletion (Args &input,
                  int &cursor_index,
                  int &cursor_char_position,
                  int match_start_point,
                  int max_return_elements,
                  bool &word_complete,
                  StringList &matches)
{
    if (IsValid())
        return m_underlying_command_sp->HandleCompletion(input,
                                                         cursor_index,
                                                         cursor_char_position,
                                                         match_start_point,
                                                         max_return_elements,
                                                         word_complete,
                                                         matches);
    return -1;
}

int
CommandAlias::HandleArgumentCompletion (Args &input,
                          int &cursor_index,
                          int &cursor_char_position,
                          OptionElementVector &opt_element_vector,
                          int match_start_point,
                          int max_return_elements,
                          bool &word_complete,
                          StringList &matches)
{
    if (IsValid())
        return m_underlying_command_sp->HandleArgumentCompletion(input,
                                                                 cursor_index,
                                                                 cursor_char_position,
                                                                 opt_element_vector,
                                                                 match_start_point,
                                                                 max_return_elements,
                                                                 word_complete,
                                                                 matches);
    return -1;
}

Options*
CommandAlias::GetOptions()
{
    if (IsValid())
        return m_underlying_command_sp->GetOptions();
    return nullptr;
}

bool
CommandAlias::Execute(const char *args_string, CommandReturnObject &result)
{
    llvm_unreachable("CommandAlias::Execute is not to be called");
}

void
CommandAlias::GetAliasExpansion (StreamString &help_string)
{
    const char* command_name = m_underlying_command_sp->GetCommandName();
    help_string.Printf ("'%s", command_name);
    
    if (m_option_args_sp)
    {
        OptionArgVector *options = m_option_args_sp.get();
        for (size_t i = 0; i < options->size(); ++i)
        {
            OptionArgPair cur_option = (*options)[i];
            std::string opt = cur_option.first;
            OptionArgValue value_pair = cur_option.second;
            std::string value = value_pair.second;
            if (opt.compare("<argument>") == 0)
            {
                help_string.Printf (" %s", value.c_str());
            }
            else
            {
                help_string.Printf (" %s", opt.c_str());
                if ((value.compare ("<no-argument>") != 0)
                    && (value.compare ("<need-argument") != 0))
                {
                    help_string.Printf (" %s", value.c_str());
                }
            }
        }
    }
    
    help_string.Printf ("'");
}

bool
CommandAlias::IsDashDashCommand ()
{
    if (m_is_dashdash_alias == eLazyBoolCalculate)
    {
        m_is_dashdash_alias = eLazyBoolNo;
        if (IsValid())
        {
            for (const OptionArgPair& opt_arg : *GetOptionArguments())
            {
                if (opt_arg.first == "<argument>" &&
                    !opt_arg.second.second.empty() &&
                    llvm::StringRef(opt_arg.second.second).endswith("--"))
                {
                    m_is_dashdash_alias = eLazyBoolYes;
                    break;
                }
            }
            // if this is a nested alias, it may be adding arguments on top of an already dash-dash alias
            if ((m_is_dashdash_alias == eLazyBoolNo) && IsNestedAlias())
                m_is_dashdash_alias = (GetUnderlyingCommand()->IsDashDashCommand() ? eLazyBoolYes : eLazyBoolNo);
        }
    }
    return (m_is_dashdash_alias == eLazyBoolYes);
}

bool
CommandAlias::IsNestedAlias ()
{
    if (GetUnderlyingCommand())
        return GetUnderlyingCommand()->IsAlias();
    return false;
}

std::pair<lldb::CommandObjectSP, OptionArgVectorSP>
CommandAlias::Desugar ()
{
    auto underlying = GetUnderlyingCommand();
    if (!underlying)
        return {nullptr,nullptr};
    
    if (underlying->IsAlias())
    {
        auto desugared = ((CommandAlias*)underlying.get())->Desugar();
        auto options = GetOptionArguments();
        options->insert(options->begin(), desugared.second->begin(), desugared.second->end());
        return {desugared.first,options};
    }

    return {underlying,GetOptionArguments()};
}

// allow CommandAlias objects to provide their own help, but fallback to the info
// for the underlying command if no customization has been provided
void
CommandAlias::SetHelp (const char * str)
{
    this->CommandObject::SetHelp(str);
    m_did_set_help = true;
}

void
CommandAlias::SetHelpLong (const char * str)
{
    this->CommandObject::SetHelpLong(str);
    m_did_set_help_long = true;
}

const char*
CommandAlias::GetHelp ()
{
    if (!m_cmd_help_short.empty() || m_did_set_help)
        return m_cmd_help_short.c_str();
    if (IsValid())
        return m_underlying_command_sp->GetHelp();
    return nullptr;
}

const char*
CommandAlias::GetHelpLong ()
{
    if (!m_cmd_help_long.empty() || m_did_set_help_long)
        return m_cmd_help_long.c_str();
    if (IsValid())
        return m_underlying_command_sp->GetHelpLong();
    return nullptr;
}