src/gromacs/commandline/cmdlineparser.cpp

   1 /*
   2  * This file is part of the GROMACS molecular simulation package.
   3  *
   4  * Copyright (c) 2010-2018, The GROMACS development team.
   5  * Copyright (c) 2019,2020, by the GROMACS development team, led by
   6  * Mark Abraham, David van der Spoel, Berk Hess, and Erik Lindahl,
   7  * and including many others, as listed in the AUTHORS file in the
   8  * top-level source directory and at http://www.gromacs.org.
   9  *
  10  * GROMACS is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU Lesser General Public License
  12  * as published by the Free Software Foundation; either version 2.1
  13  * of the License, or (at your option) any later version.
  14  *
  15  * GROMACS is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  * Lesser General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU Lesser General Public
  21  * License along with GROMACS; if not, see
  22  * http://www.gnu.org/licenses, or write to the Free Software Foundation,
  23  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA.
  24  *
  25  * If you want to redistribute modifications to GROMACS, please
  26  * consider that scientific software is very special. Version
  27  * control is crucial - bugs must be traceable. We will be happy to
  28  * consider code for inclusion in the official distribution, but
  29  * derived work must not be called official GROMACS. Details are found
  30  * in the README & COPYING files - if they are missing, get the
  31  * official version at http://www.gromacs.org.
  32  *
  33  * To help us fund GROMACS development, we humbly ask that you cite
  34  * the research papers on the package. Check out http://www.gromacs.org.
  35  */
  36 /*! \internal \file
  37  * \brief
  38  * Implements gmx::CommandLineParser.
  39  *
  40  * \author Teemu Murtola <teemu.murtola@gmail.com>
  41  * \ingroup module_commandline
  42  */
  43 #include "gmxpre.h"
  44
  45 #include "cmdlineparser.h"
  46
  47 #include <cstdlib>
  48
  49 #include <string>
  50 #include <vector>
  51
  52 #include "gromacs/options/optionsassigner.h"
  53 #include "gromacs/utility/basedefinitions.h"
  54 #include "gromacs/utility/exceptions.h"
  55
  56 namespace gmx
  57 {
  58
  59 /********************************************************************
  60  * CommandLineParser::Impl
  61  */
  62
  63 /*! \internal \brief
  64  * Private implementation class for CommandLineParser.
  65  *
  66  * \ingroup module_commandline
  67  */
  68 class CommandLineParser::Impl
  69 {
  70 public:
  71     //! Sets the options object to parse to.
  72     explicit Impl(Options* options);
  73
  74     /*! \brief
  75      * Determines whether a cmdline parameter starts an option and the name
  76      * of that option.
  77      *
  78      * \param[in] arg  Individual argument from \c argv.
  79      * \returns The beginning of the option name in \p arg, or NULL if
  80      *     \p arg does not look like an option.
  81      */
  82     static const char* toOptionName(const char* arg);
  83
  84     //! Helper object for assigning the options.
  85     OptionsAssigner assigner_;
  86     //! Whether to allow and skip unknown options.
  87     bool bSkipUnknown_;
  88     /*! \brief Whether to allow positional arguments
  89      *
  90      * These are not options (no leading hyphen), and come before
  91      * all options. */
  92     bool bAllowPositionalArguments_;
  93 };
  94
  95 CommandLineParser::Impl::Impl(Options* options) :
  96     assigner_(options),
  97     bSkipUnknown_(false),
  98     bAllowPositionalArguments_(false)
  99 {
 100     assigner_.setAcceptBooleanNoPrefix(true);
 101 }
 102
 103 const char* CommandLineParser::Impl::toOptionName(const char* arg)
 104 {
 105     // Lone '-' or '--' is not an option.
 106     if (arg[0] != '-' || arg[1] == '\0' || (arg[1] == '-' && arg[2] == '\0'))
 107     {
 108         return nullptr;
 109     }
 110     // Something starting with '--' is always an option.
 111     if (arg[1] == '-')
 112     {
 113         return arg + 2;
 114     }
 115     // Don't return numbers as option names.
 116     char* endptr;
 117     // We are only interested in endptr, not in the actual value.
 118     GMX_IGNORE_RETURN_VALUE(std::strtod(arg, &endptr));
 119     if (*endptr == '\0')
 120     {
 121         return nullptr;
 122     }
 123     return arg + 1;
 124 }
 125
 126 /********************************************************************
 127  * CommandLineParser
 128  */
 129
 130 CommandLineParser::CommandLineParser(Options* options) : impl_(new Impl(options)) {}
 131
 132 CommandLineParser::~CommandLineParser() {}
 133
 134 CommandLineParser& CommandLineParser::skipUnknown(bool bEnabled)
 135 {
 136     impl_->bSkipUnknown_ = bEnabled;
 137     return *this;
 138 }
 139
 140 CommandLineParser& CommandLineParser::allowPositionalArguments(bool bEnabled)
 141 {
 142     impl_->bAllowPositionalArguments_ = bEnabled;
 143     return *this;
 144 }
 145
 146 void CommandLineParser::parse(int* argc, char* argv[])
 147 {
 148     ExceptionInitializer errors("Invalid command-line options");
 149     std::string          currentContext;
 150     bool                 bInOption = false;
 151
 152     // Note that this function gets called multiple times in typical
 153     // cases of calling gmx. Command lines like "gmx -hidden mdrun -h"
 154     // work because the first call has argv[0] == "gmx" and skips
 155     // unknown things, and the second has argv[0] == "mdrun".
 156     int i = 1, newi = 1;
 157
 158     // First, process any permitted leading positional arguments.
 159     for (; i < *argc; ++i)
 160     {
 161         const char* const arg = argv[i];
 162         if (impl_->toOptionName(arg) != nullptr)
 163         {
 164             // If we find an option, no more positional arguments
 165             // can be handled.
 166             break;
 167         }
 168
 169         if (!impl_->bAllowPositionalArguments_)
 170         {
 171             GMX_THROW(
 172                     InvalidInputError(
 173                             "Positional argument '" + std::string(arg)
 174                             + "' cannot be accepted. "
 175                               "Perhaps you forgot to put a hyphen before an option name."));
 176         }
 177         // argv[i] is not an option, so preserve it in the argument list
 178         // by incrementing newi. There's no need to copy argv contents
 179         // because they cannot have changed yet.
 180         ++newi;
 181     }
 182
 183     // Now handle the option arguments.
 184     impl_->assigner_.start();
 185     for (; i < *argc; ++i)
 186     {
 187         const char* const arg        = argv[i];
 188         const char* const optionName = impl_->toOptionName(arg);
 189         if (optionName != nullptr)
 190         {
 191             if (bInOption)
 192             {
 193                 try
 194                 {
 195                     impl_->assigner_.finishOption();
 196                 }
 197                 catch (UserInputError& ex)
 198                 {
 199                     ex.prependContext(currentContext);
 200                     errors.addCurrentExceptionAsNested();
 201                 }
 202             }
 203             currentContext = "In command-line option " + std::string(arg);
 204             try
 205             {
 206                 bInOption = impl_->assigner_.tryStartOption(optionName);
 207                 if (!bInOption)
 208                 {
 209                     currentContext.clear();
 210                     if (!impl_->bSkipUnknown_)
 211                     {
 212                         std::string message = "Unknown command-line option " + std::string(arg);
 213                         GMX_THROW(InvalidInputError(message));
 214                     }
 215                 }
 216             }
 217             catch (UserInputError& ex)
 218             {
 219                 // If tryStartOption() throws, make sure that the rest gets
 220                 // ignored.
 221                 // TODO: Consider whether we should remove the option from the
 222                 // command line nonetheless, as it is recognized, but just
 223                 // invalid.
 224                 bInOption = false;
 225                 ex.prependContext(currentContext);
 226                 errors.addCurrentExceptionAsNested();
 227                 currentContext.clear();
 228             }
 229         }
 230         else if (bInOption)
 231         {
 232             try
 233             {
 234                 impl_->assigner_.appendValue(arg);
 235             }
 236             // TODO: Consider if some types of exceptions would be better left
 237             // unhandled.
 238             catch (GromacsException& ex)
 239             {
 240                 ex.prependContext(currentContext);
 241                 errors.addCurrentExceptionAsNested();
 242             }
 243         }
 244         // Retain unrecognized options if applicable.
 245         if (!bInOption && impl_->bSkipUnknown_)
 246         {
 247             argv[newi] = argv[i];
 248             ++newi;
 249         }
 250     }
 251     // Update the args if argv was modified.
 252     if (impl_->bSkipUnknown_)
 253     {
 254         *argc      = newi;
 255         argv[newi] = nullptr;
 256     }
 257
 258     // Finish the last option.
 259     if (bInOption)
 260     {
 261         try
 262         {
 263             impl_->assigner_.finishOption();
 264         }
 265         catch (UserInputError& ex)
 266         {
 267             ex.prependContext(currentContext);
 268             errors.addCurrentExceptionAsNested();
 269         }
 270     }
 271     impl_->assigner_.finish();
 272     if (errors.hasNestedExceptions())
 273     {
 274         // TODO: This exception type may not always be appropriate.
 275         GMX_THROW(InvalidInputError(errors));
 276     }
 277 }
 278
 279 } // namespace gmx