https://github.com/Kitware/CMake
Revision d89e10cd58e5f9e21cbd466e56a1890e2811bee0 authored by Brad King on 14 July 2017, 17:52:53 UTC, committed by Brad King on 14 July 2017, 18:05:22 UTC
The code

    add_library(A OBJECT a.c)
    target_sources(A PRIVATE $<TARGET_OBJECTS:A>)

used to crash CMake via infinite recursion while evaluating the
generator expression.  Then the change in commit v3.9.0-rc1~266^2~1
(cmGeneratorTarget: Replace source classifier implementation,
2017-04-07) avoided the infinite recursion because GetKindedSources now
creates a map entry and initializes it once.  If it is called again on
the same target during that initialization, the partially computed
results are returned.  This is still wrong but does not crash.
Detect and diagnose this case instead.

Co-Author: Ben Boeckel <ben.boeckel@kitware.com>
Fixes: #16578
1 parent 25b72e9
Raw File
Tip revision: d89e10cd58e5f9e21cbd466e56a1890e2811bee0 authored by Brad King on 14 July 2017, 17:52:53 UTC
Diagnose object library self-reference
Tip revision: d89e10c
cmCommandArgumentParserHelper.cxx
/* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
   file Copyright.txt or https://cmake.org/licensing for details.  */
#include "cmCommandArgumentParserHelper.h"

#include "cmCommandArgumentLexer.h"
#include "cmMakefile.h"
#include "cmState.h"
#include "cmSystemTools.h"
#include "cmake.h"

#include <iostream>
#include <sstream>
#include <string.h>

int cmCommandArgument_yyparse(yyscan_t yyscanner);
//
cmCommandArgumentParserHelper::cmCommandArgumentParserHelper()
{
  this->WarnUninitialized = false;
  this->CheckSystemVars = false;
  this->FileLine = -1;
  this->FileName = CM_NULLPTR;
  this->RemoveEmpty = true;
  this->EmptyVariable[0] = 0;
  strcpy(this->DCURLYVariable, "${");
  strcpy(this->RCURLYVariable, "}");
  strcpy(this->ATVariable, "@");
  strcpy(this->DOLLARVariable, "$");
  strcpy(this->LCURLYVariable, "{");
  strcpy(this->BSLASHVariable, "\\");

  this->NoEscapeMode = false;
  this->ReplaceAtSyntax = false;
}

cmCommandArgumentParserHelper::~cmCommandArgumentParserHelper()
{
  this->CleanupParser();
}

void cmCommandArgumentParserHelper::SetLineFile(long line, const char* file)
{
  this->FileLine = line;
  this->FileName = file;
}

char* cmCommandArgumentParserHelper::AddString(const std::string& str)
{
  if (str.empty()) {
    return this->EmptyVariable;
  }
  char* stVal = new char[str.size() + 1];
  strcpy(stVal, str.c_str());
  this->Variables.push_back(stVal);
  return stVal;
}

char* cmCommandArgumentParserHelper::ExpandSpecialVariable(const char* key,
                                                           const char* var)
{
  if (!key) {
    return this->ExpandVariable(var);
  }
  if (!var) {
    return this->EmptyVariable;
  }
  if (strcmp(key, "ENV") == 0) {
    std::string str;
    if (cmSystemTools::GetEnv(var, str)) {
      if (this->EscapeQuotes) {
        return this->AddString(cmSystemTools::EscapeQuotes(str));
      }
      return this->AddString(str);
    }
    return this->EmptyVariable;
  }
  if (strcmp(key, "CACHE") == 0) {
    if (const char* c =
          this->Makefile->GetState()->GetInitializedCacheValue(var)) {
      if (this->EscapeQuotes) {
        return this->AddString(cmSystemTools::EscapeQuotes(c));
      }
      return this->AddString(c);
    }
    return this->EmptyVariable;
  }
  std::ostringstream e;
  e << "Syntax $" << key << "{} is not supported.  "
    << "Only ${}, $ENV{}, and $CACHE{} are allowed.";
  this->SetError(e.str());
  return CM_NULLPTR;
}

char* cmCommandArgumentParserHelper::ExpandVariable(const char* var)
{
  if (!var) {
    return CM_NULLPTR;
  }
  if (this->FileLine >= 0 && strcmp(var, "CMAKE_CURRENT_LIST_LINE") == 0) {
    std::ostringstream ostr;
    ostr << this->FileLine;
    return this->AddString(ostr.str());
  }
  const char* value = this->Makefile->GetDefinition(var);
  if (!value && !this->RemoveEmpty) {
    // check to see if we need to print a warning
    // if strict mode is on and the variable has
    // not been "cleared"/initialized with a set(foo ) call
    if (this->WarnUninitialized && !this->Makefile->VariableInitialized(var)) {
      if (this->CheckSystemVars ||
          cmSystemTools::IsSubDirectory(this->FileName,
                                        this->Makefile->GetHomeDirectory()) ||
          cmSystemTools::IsSubDirectory(
            this->FileName, this->Makefile->GetHomeOutputDirectory())) {
        std::ostringstream msg;
        msg << "uninitialized variable \'" << var << "\'";
        this->Makefile->IssueMessage(cmake::AUTHOR_WARNING, msg.str());
      }
    }
    return CM_NULLPTR;
  }
  if (this->EscapeQuotes && value) {
    return this->AddString(cmSystemTools::EscapeQuotes(value));
  }
  return this->AddString(value ? value : "");
}

char* cmCommandArgumentParserHelper::ExpandVariableForAt(const char* var)
{
  if (this->ReplaceAtSyntax) {
    // try to expand the variable
    char* ret = this->ExpandVariable(var);
    // if the return was 0 and we want to replace empty strings
    // then return an empty string
    if (!ret && this->RemoveEmpty) {
      return this->AddString("");
    }
    // if the ret was not 0, then return it
    if (ret) {
      return ret;
    }
  }
  // at this point we want to put it back because of one of these cases:
  // - this->ReplaceAtSyntax is false
  // - this->ReplaceAtSyntax is true, but this->RemoveEmpty is false,
  //   and the variable was not defined
  std::string ref = "@";
  ref += var;
  ref += "@";
  return this->AddString(ref);
}

char* cmCommandArgumentParserHelper::CombineUnions(char* in1, char* in2)
{
  if (!in1) {
    return in2;
  }
  if (!in2) {
    return in1;
  }
  size_t len = strlen(in1) + strlen(in2) + 1;
  char* out = new char[len];
  strcpy(out, in1);
  strcat(out, in2);
  this->Variables.push_back(out);
  return out;
}

void cmCommandArgumentParserHelper::AllocateParserType(
  cmCommandArgumentParserHelper::ParserType* pt, const char* str, int len)
{
  pt->str = CM_NULLPTR;
  if (len == 0) {
    len = static_cast<int>(strlen(str));
  }
  if (len == 0) {
    return;
  }
  pt->str = new char[len + 1];
  strncpy(pt->str, str, len);
  pt->str[len] = 0;
  this->Variables.push_back(pt->str);
}

bool cmCommandArgumentParserHelper::HandleEscapeSymbol(
  cmCommandArgumentParserHelper::ParserType* pt, char symbol)
{
  switch (symbol) {
    case '\\':
    case '"':
    case ' ':
    case '#':
    case '(':
    case ')':
    case '$':
    case '@':
    case '^':
      this->AllocateParserType(pt, &symbol, 1);
      break;
    case ';':
      this->AllocateParserType(pt, "\\;", 2);
      break;
    case 't':
      this->AllocateParserType(pt, "\t", 1);
      break;
    case 'n':
      this->AllocateParserType(pt, "\n", 1);
      break;
    case 'r':
      this->AllocateParserType(pt, "\r", 1);
      break;
    case '0':
      this->AllocateParserType(pt, "\0", 1);
      break;
    default: {
      std::ostringstream e;
      e << "Invalid escape sequence \\" << symbol;
      this->SetError(e.str());
    }
      return false;
  }
  return true;
}

void cmCommandArgument_SetupEscapes(yyscan_t yyscanner, bool noEscapes);

int cmCommandArgumentParserHelper::ParseString(const char* str, int verb)
{
  if (!str) {
    return 0;
  }
  this->Verbose = verb;
  this->InputBuffer = str;
  this->InputBufferPos = 0;
  this->CurrentLine = 0;

  this->Result = "";

  yyscan_t yyscanner;
  cmCommandArgument_yylex_init(&yyscanner);
  cmCommandArgument_yyset_extra(this, yyscanner);
  cmCommandArgument_SetupEscapes(yyscanner, this->NoEscapeMode);
  int res = cmCommandArgument_yyparse(yyscanner);
  cmCommandArgument_yylex_destroy(yyscanner);
  if (res != 0) {
    return 0;
  }

  this->CleanupParser();

  if (Verbose) {
    std::cerr << "Expanding [" << str << "] produced: [" << this->Result << "]"
              << std::endl;
  }
  return 1;
}

void cmCommandArgumentParserHelper::CleanupParser()
{
  std::vector<char*>::iterator sit;
  for (sit = this->Variables.begin(); sit != this->Variables.end(); ++sit) {
    delete[] * sit;
  }
  this->Variables.erase(this->Variables.begin(), this->Variables.end());
}

int cmCommandArgumentParserHelper::LexInput(char* buf, int maxlen)
{
  if (maxlen < 1) {
    return 0;
  }
  if (this->InputBufferPos < this->InputBuffer.size()) {
    buf[0] = this->InputBuffer[this->InputBufferPos++];
    if (buf[0] == '\n') {
      this->CurrentLine++;
    }
    return (1);
  }
  buf[0] = '\n';
  return (0);
}

void cmCommandArgumentParserHelper::Error(const char* str)
{
  unsigned long pos = static_cast<unsigned long>(this->InputBufferPos);
  std::ostringstream ostr;
  ostr << str << " (" << pos << ")";
  this->SetError(ostr.str());
}

void cmCommandArgumentParserHelper::SetMakefile(const cmMakefile* mf)
{
  this->Makefile = mf;
  this->WarnUninitialized = mf->GetCMakeInstance()->GetWarnUninitialized();
  this->CheckSystemVars = mf->GetCMakeInstance()->GetCheckSystemVars();
}

void cmCommandArgumentParserHelper::SetResult(const char* value)
{
  if (!value) {
    this->Result = "";
    return;
  }
  this->Result = value;
}

void cmCommandArgumentParserHelper::SetError(std::string const& msg)
{
  // Keep only the first error.
  if (this->ErrorString.empty()) {
    this->ErrorString = msg;
  }
}
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