/* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying

   file LICENSE.rst or https://cmake.org/licensing for details.  */

#include "cmPolicies.h"

#include <cassert>

#include <cctype>

#include <cstdio>

#include <cstring>

#include <sstream>

#include <vector>

#include "cmListFileCache.h"

#include "cmMakefile.h"

#include "cmMessageType.h"

#include "cmStateSnapshot.h"

#include "cmStringAlgorithms.h"

#include "cmSystemTools.h"

#include "cmValue.h"

#include "cmVersion.h"

static bool stringToId(char const* input, cmPolicies::PolicyID& pid)

{

  assert(input);

  if (strlen(input) != 7) {

    return false;

  }

  if (!cmHasLiteralPrefix(input, "CMP")) {

    return false;

  }

  if (cmHasLiteralSuffix(input, "0000")) {

    pid = cmPolicies::CMP0000;

    return true;

  }

  for (int i = 3; i < 7; ++i) {

    if (!isdigit(*(input + i))) {

      return false;

    }

  }

  long id;

  if (!cmStrToLong(input + 3, &id)) {

    return false;

  }

  if (id >= cmPolicies::CMPCOUNT) {

    return false;

  }

  pid = static_cast<cmPolicies::PolicyID>(id);

  return true;

}

#define CM_SELECT_ID_VERSION(F, A1, A2, A3, A4, A5, A6) F(A1, A3, A4, A5)

#define CM_FOR_EACH_POLICY_ID_VERSION(POLICY)                                 \

  CM_FOR_EACH_POLICY_TABLE(POLICY, CM_SELECT_ID_VERSION)

#define CM_SELECT_ID_DOC(F, A1, A2, A3, A4, A5, A6) F(A1, A2)

#define CM_FOR_EACH_POLICY_ID_DOC(POLICY)                                     \

  CM_FOR_EACH_POLICY_TABLE(POLICY, CM_SELECT_ID_DOC)

#define CM_SELECT_ID_STATUS(F, A1, A2, A3, A4, A5, A6) F(A1, A6)

#define CM_FOR_EACH_POLICY_ID_STATUS(POLICY)                                  \

  CM_FOR_EACH_POLICY_TABLE(POLICY, CM_SELECT_ID_STATUS)

static char const* idToString(cmPolicies::PolicyID id)

{

  switch (id) {

#define POLICY_CASE(ID)                                                       \

  case cmPolicies::ID:                                                        \

    return #ID;

    CM_FOR_EACH_POLICY_ID(POLICY_CASE)

#undef POLICY_CASE

    case cmPolicies::CMPCOUNT:

      return nullptr;

  }

  return nullptr;

}

static char const* idToVersion(cmPolicies::PolicyID id)

{

  switch (id) {

#define POLICY_CASE(ID, V_MAJOR, V_MINOR, V_PATCH)                            \

  case cmPolicies::ID:                                                        \

    return #V_MAJOR "." #V_MINOR "." #V_PATCH;

    // NOLINTNEXTLINE(bugprone-branch-clone)

    CM_FOR_EACH_POLICY_ID_VERSION(POLICY_CASE)

#undef POLICY_CASE

    case cmPolicies::CMPCOUNT:

      return nullptr;

  }

  return nullptr;

}

static bool isPolicyNewerThan(cmPolicies::PolicyID id, unsigned int majorV,

                              unsigned int minorV, unsigned int patchV)

{

  switch (id) {

#define POLICY_CASE(ID, V_MAJOR, V_MINOR, V_PATCH)                            \

  case cmPolicies::ID:                                                        \

    return (majorV < (V_MAJOR) ||                                             \

            (majorV == (V_MAJOR) && minorV + 1 < (V_MINOR) + 1) ||            \

            (majorV == (V_MAJOR) && minorV == (V_MINOR) &&                    \

             patchV + 1 < (V_PATCH) + 1));

    // NOLINTNEXTLINE(bugprone-branch-clone)

    CM_FOR_EACH_POLICY_ID_VERSION(POLICY_CASE)

#undef POLICY_CASE

    case cmPolicies::CMPCOUNT:

      return false;

  }

  return false;

}

static char const* idToShortDescription(cmPolicies::PolicyID id)

{

  switch (id) {

#define POLICY_CASE(ID, SHORT_DESCRIPTION)                                    \

  case cmPolicies::ID:                                                        \

    return SHORT_DESCRIPTION;

    CM_FOR_EACH_POLICY_ID_DOC(POLICY_CASE)

#undef POLICY_CASE

    case cmPolicies::CMPCOUNT:

      return nullptr;

  }

  return nullptr;

}

namespace {

cmPolicies::PolicyStatus idToStatus(cmPolicies::PolicyID id)

{

  switch (id) {

#define POLICY_CASE(ID, STATUS)                                               \

  case cmPolicies::ID:                                                        \

    return cmPolicies::STATUS;

    // NOLINTNEXTLINE(bugprone-branch-clone)

    CM_FOR_EACH_POLICY_ID_STATUS(POLICY_CASE)

#undef POLICY_CASE

    case cmPolicies::CMPCOUNT:

      break;

  }

  return cmPolicies::WARN;

}

}

static void DiagnoseAncientPolicies(

  std::vector<cmPolicies::PolicyID> const& ancient, unsigned int majorVer,

  unsigned int minorVer, unsigned int patchVer, cmMakefile* mf)

{

  std::ostringstream e;

  e << "The project requests behavior compatible with CMake version \""

    << majorVer << '.' << minorVer << '.' << patchVer

    << "\", which requires the OLD behavior for some policies:\n";

  for (cmPolicies::PolicyID i : ancient) {

    e << "  " << idToString(i) << ": " << idToShortDescription(i) << '\n';

  }

  e << "However, this version of CMake no longer supports the OLD "

       "behavior for these policies.  "

       "Please either update your CMakeLists.txt files to conform to "

       "the new behavior or use an older version of CMake that still "

       "supports the old behavior.";

  mf->IssueMessage(MessageType::FATAL_ERROR, e.str());

}

static bool GetPolicyDefault(cmMakefile* mf, std::string const& policy,

                             cmPolicies::PolicyStatus* defaultSetting)

{

  std::string defaultVar = cmStrCat("CMAKE_POLICY_DEFAULT_", policy);

  std::string const& defaultValue = mf->GetSafeDefinition(defaultVar);

  if (defaultValue == "NEW") {

    *defaultSetting = cmPolicies::NEW;

  } else if (defaultValue == "OLD") {

    *defaultSetting = cmPolicies::OLD;

  } else if (defaultValue.empty()) {

    *defaultSetting = cmPolicies::WARN;

  } else {

    mf->IssueMessage(

      MessageType::FATAL_ERROR,

      cmStrCat(defaultVar, " has value \"", defaultValue,

               R"(" but must be "OLD", "NEW", or "" (empty).)"));

    return false;

  }

  return true;

}

bool cmPolicies::ApplyPolicyVersion(cmMakefile* mf,

                                    std::string const& version_min,

                                    std::string const& version_max,

                                    WarnCompat warnCompat)

{

  // Parse components of the minimum version.

  unsigned int minMajor = 2;

  unsigned int minMinor = 0;

  unsigned int minPatch = 0;

  unsigned int minTweak = 0;

  if (sscanf(version_min.c_str(), "%u.%u.%u.%u", &minMajor, &minMinor,

             &minPatch, &minTweak) < 2) {

    mf->IssueMessage(

      MessageType::FATAL_ERROR,

      cmStrCat("Invalid policy version value \"", version_min,

               "\".  "

               "A numeric major.minor[.patch[.tweak]] must be given."));

    return false;

  }

  // it is an error if the policy version is less than 2.4

  if (minMajor < 2 || (minMajor == 2 && minMinor < 4)) {

    mf->IssueMessage(

      MessageType::FATAL_ERROR,

      "Compatibility with CMake < 2.4 is not supported by CMake >= 3.0.  "

      "For compatibility with older versions please use any CMake 2.8.x "

      "release or lower.");

    return false;

  }

  // It is an error if the policy version is greater than the running

  // CMake.

  if (minMajor > cmVersion::GetMajorVersion() ||

      (minMajor == cmVersion::GetMajorVersion() &&

       minMinor > cmVersion::GetMinorVersion()) ||

      (minMajor == cmVersion::GetMajorVersion() &&

       minMinor == cmVersion::GetMinorVersion() &&

       minPatch > cmVersion::GetPatchVersion()) ||

      (minMajor == cmVersion::GetMajorVersion() &&

       minMinor == cmVersion::GetMinorVersion() &&

       minPatch == cmVersion::GetPatchVersion() &&

       minTweak > cmVersion::GetTweakVersion())) {

    mf->IssueMessage(

      MessageType::FATAL_ERROR,

      cmStrCat("An attempt was made to set the policy version of CMake to \"",

               version_min,

               "\" which is greater than this version of CMake.  "

               "This is not allowed because the greater version may have new "

               "policies not known to this CMake.  "

               "You may need a newer CMake version to build this project."));

    return false;

  }

  unsigned int polMajor = minMajor;

  unsigned int polMinor = minMinor;

  unsigned int polPatch = minPatch;

  if (!version_max.empty()) {

    // Parse components of the maximum version.

    unsigned int maxMajor = 0;

    unsigned int maxMinor = 0;

    unsigned int maxPatch = 0;

    unsigned int maxTweak = 0;

    if (sscanf(version_max.c_str(), "%u.%u.%u.%u", &maxMajor, &maxMinor,

               &maxPatch, &maxTweak) < 2) {

      mf->IssueMessage(

        MessageType::FATAL_ERROR,

        cmStrCat("Invalid policy max version value \"", version_max,

                 "\".  "

                 "A numeric major.minor[.patch[.tweak]] must be given."));

      return false;

    }

    // It is an error if the min version is greater than the max version.

    if (minMajor > maxMajor || (minMajor == maxMajor && minMinor > maxMinor) ||

        (minMajor == maxMajor && minMinor == maxMinor &&

         minPatch > maxPatch) ||

        (minMajor == maxMajor && minMinor == maxMinor &&

         minPatch == maxPatch && minTweak > maxTweak)) {

      mf->IssueMessage(

        MessageType::FATAL_ERROR,

        cmStrCat("Policy VERSION range \"", version_min, "...", version_max,

                 "\" specifies a larger minimum than maximum."));

      return false;

    }

    // Use the max version as the policy version.

    polMajor = maxMajor;

    polMinor = maxMinor;

    polPatch = maxPatch;

  }

  return cmPolicies::ApplyPolicyVersion(mf, polMajor, polMinor, polPatch,

                                        warnCompat);

}

namespace {

bool IsFromLegacyInstallEXPORT(cmMakefile* mf, unsigned int majorVer,

                               unsigned int minorVer, unsigned int patchVer)

{

  return majorVer == 2 && minorVer == 6 && patchVer == 0 &&

    mf->GetStateSnapshot().CanPopPolicyScope() &&

    cmSystemTools::Strucmp(mf->GetBacktrace().Top().Name.c_str(),

                           "cmake_policy") == 0;

}

#define ADVICE_UPDATE_VERSION_ARGUMENT                                        \

  "Update the VERSION argument <min> value.  Or, use the <min>...<max> "      \

  "syntax to tell CMake that the project requires at least <min> but has "    \

  "been updated to work with policies introduced by <max> or earlier."

}

bool cmPolicies::ApplyPolicyVersion(cmMakefile* mf, unsigned int majorVer,

                                    unsigned int minorVer,

                                    unsigned int patchVer,

                                    WarnCompat warnCompat)

{

  cmValue varVer = mf->GetDefinition("CMAKE_POLICY_VERSION_MINIMUM");

  if (!varVer.IsEmpty()) {

    unsigned int varMajor = 0;

    unsigned int varMinor = 0;

    unsigned int varPatch = 0;

    unsigned int varTweak = 0;

    if (sscanf(varVer.GetCStr(), "%u.%u.%u.%u", &varMajor, &varMinor,

               &varPatch, &varTweak) < 2) {

      mf->IssueMessage(

        MessageType::FATAL_ERROR,

        cmStrCat("Invalid CMAKE_POLICY_VERSION_MINIMUM value \"", varVer,

                 "\".  "

                 "A numeric major.minor[.patch[.tweak]] must be given."));

      return false;

    }

    if (varMajor > majorVer || (varMajor == majorVer && varMinor > minorVer) ||

        (varMajor == majorVer && varMinor == minorVer &&

         varPatch > patchVer)) {

      majorVer = varMajor;

      minorVer = varMinor;

      patchVer = varPatch;

    }

  }

  // Error on policy versions for which support has been removed.

  if (majorVer < 3 || (majorVer == 3 && minorVer < 5)) {

    if (IsFromLegacyInstallEXPORT(mf, majorVer, minorVer, patchVer)) {

      // Silently tolerate cmake_policy calls generated by install(EXPORT)

      // in CMake versions prior to 3.18.

      majorVer = 3;

      minorVer = 5;

      patchVer = 0;

    } else {

      mf->IssueMessage(MessageType::FATAL_ERROR,

                       "Compatibility with CMake < 3.5 has been removed "

                       "from CMake.\n" ADVICE_UPDATE_VERSION_ARGUMENT "\n"

                       "Or, add -DCMAKE_POLICY_VERSION_MINIMUM=3.5 to try "

                       "configuring anyway.");

      cmSystemTools::SetFatalErrorOccurred();

      return false;

    }

  } else if (majorVer == 3 && minorVer < 10 && warnCompat == WarnCompat::On) {

    // Warn about policy versions for which support will be removed.

    mf->IssueMessage(

      MessageType::DEPRECATION_WARNING,

      "Compatibility with CMake < 3.10 will be removed from "

      "a future version of CMake.\n" ADVICE_UPDATE_VERSION_ARGUMENT);

  }

  // now loop over all the policies and set them as appropriate

  std::vector<cmPolicies::PolicyID> ancientPolicies;

  for (PolicyID pid = cmPolicies::CMP0000; pid != cmPolicies::CMPCOUNT;

       pid = static_cast<PolicyID>(pid + 1)) {

    if (isPolicyNewerThan(pid, majorVer, minorVer, patchVer)) {

      if (cmPolicies::IsRemoved(pid)) {

        ancientPolicies.push_back(pid);

      } else {

        cmPolicies::PolicyStatus status = cmPolicies::WARN;

        if (!GetPolicyDefault(mf, idToString(pid), &status) ||

            !mf->SetPolicy(pid, status)) {

          return false;

        }

      }

    } else {

      if (!mf->SetPolicy(pid, cmPolicies::NEW)) {

        return false;

      }

    }

  }

  // Make sure the project does not use any ancient policies.

  if (!ancientPolicies.empty()) {

    DiagnoseAncientPolicies(ancientPolicies, majorVer, minorVer, patchVer, mf);

    cmSystemTools::SetFatalErrorOccurred();

    return false;

  }

  return true;

}

bool cmPolicies::GetPolicyID(char const* id, cmPolicies::PolicyID& pid)

{

  return stringToId(id, pid);

}

//! return a warning string for a given policy

std::string cmPolicies::GetPolicyWarning(cmPolicies::PolicyID id)

{

  return cmStrCat("Policy ", idToString(id),

                  " is not set: ", idToShortDescription(id),

                  "  "

                  "Run \"cmake --help-policy ",

                  idToString(id),

                  "\" for "

                  "policy details.  "

                  "Use the cmake_policy command to set the policy "

                  "and suppress this warning.");

}

std::string cmPolicies::GetPolicyDeprecatedWarning(cmPolicies::PolicyID id)

{

  return cmStrCat(

    "The OLD behavior for policy ", idToString(id),

    " "

    "will be removed from a future version of CMake.\n"

    "The cmake-policies(7) manual explains that the OLD behaviors of all "

    "policies are deprecated and that a policy should be set to OLD only "

    "under specific short-term circumstances.  Projects should be ported "

    "to the NEW behavior and not rely on setting a policy to OLD.");

}

bool cmPolicies::IsRemoved(cmPolicies::PolicyID id)

{

  return idToStatus(id) == cmPolicies::NEW;

}

std::string cmPolicies::GetRemovedPolicyError(cmPolicies::PolicyID id)

{

  std::string pid = idToString(id);

  return cmStrCat(

    "Policy ", pid,

    " may not be set to OLD behavior because this "

    "version of CMake no longer supports it.  "

    "The policy was introduced in CMake version ",

    idToVersion(id),

    ", and use of NEW behavior is now required."

    "\n"

    "Please either update your CMakeLists.txt files to conform to "

    "the new behavior or use an older version of CMake that still "

    "supports the old behavior.  Run cmake --help-policy ",

    pid, " for more information.");

}

cmPolicies::PolicyStatus cmPolicies::PolicyMap::Get(

  cmPolicies::PolicyID id) const

{

  PolicyStatus status = cmPolicies::WARN;

  if (this->Status[(POLICY_STATUS_COUNT * id) + OLD]) {

    status = cmPolicies::OLD;

  } else if (this->Status[(POLICY_STATUS_COUNT * id) + NEW]) {

    status = cmPolicies::NEW;

  }

  return status;

}

void cmPolicies::PolicyMap::Set(cmPolicies::PolicyID id,

                                cmPolicies::PolicyStatus status)

{

  this->Status[(POLICY_STATUS_COUNT * id) + OLD] = (status == OLD);

  this->Status[(POLICY_STATUS_COUNT * id) + WARN] = (status == WARN);

  this->Status[(POLICY_STATUS_COUNT * id) + NEW] = (status == NEW);

}

bool cmPolicies::PolicyMap::IsDefined(cmPolicies::PolicyID id) const

{

  return this->Status[(POLICY_STATUS_COUNT * id) + OLD] ||

    this->Status[(POLICY_STATUS_COUNT * id) + WARN] ||

    this->Status[(POLICY_STATUS_COUNT * id) + NEW];

}

bool cmPolicies::PolicyMap::IsEmpty() const

{

  return this->Status.none();

}