/** @file

    $Id$

    $Date$
    $Author$

    @copy © Marc Wäckerlin
    @license LGPL, see file <a href="license.html">COPYING</a>

    $Log$
    Revision 1.7  2004/10/13 10:47:15  marc
    no more need for ldd in StackTrace, read from /proc/self/maps

    Revision 1.6  2004/10/11 15:58:51  marc
    First version with working support for shared libraries!

    Revision 1.5  2004/10/07 16:59:12  marc
    new method createSymtable that takes a list of arguments
     -> untested!

    Revision 1.4  2004/10/07 09:32:45  marc
    correction in parameter (const&)

    Revision 1.3  2004/08/28 16:21:25  marc
    mrw-c++-0.92 (mrw)
    - new file: version.cpp
    - new file header for all sources
    - work around warning in mrw::auto<T>
    - possibility to compile without log4cxx
    - work around bugs in demangle.h and libiberty.h
    - corrections in documentation
    - added simple tracing mechanism
    - more warnings
    - small corrections in Auto<>::Free and a new test for it
    - possibility to compile without stack trace

*/
#include <mrw/stacktrace.hpp>
#include <mrw/exec.hpp>
#include <mrw/string.hpp>
#include <mrw/list.hpp>
#include <mrw/stdext.hpp>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <fcntl.h>
#include <assert.h>
#include <math.h>
#include <fstream>
#include <algorithm>
#include <list>
#if defined(__solaris__)
#include <sys/old_procfs.h>
#endif
#if defined (__GLIBC__)
#include <execinfo.h>
#endif
#include <bfd.h>
extern "C" {

  /// @bug redefined in libiberty.h
# define HAVE_DECL_BASENAME 1
  /// @bug redefined in libiberty.h
# define HAVE_DECL_ASPRINTF 1
  /// @bug redefined in libiberty.h
# define HAVE_DECL_VASPRINTF 1
/** @bug

       - in file file: /usr/include/demangle.h
       - of package:   binutils-2.15.90.0.1.1-31

      An idiot unfortunately abused the C++ keyword @c typename as
      variable name to @c cplus_demangle_fill_builtin_type, so I have
      to work around it.
  */      
# define typename anotherNameThatsNotAKeyword
#   include <demangle.h>
# undef typename
//   // copied from demangle.h because of compiler warnings in libliberty.h
//   // (... throws different exception)
// #define DMGL_PARAMS	 (1 << 0)	/* Include function args */
// #define DMGL_ANSI	 (1 << 1)	/* Include const, volatile, etc */
//   /// @bug demangle.h includes libiberty.h which throws different
//   ///      exceptions for the same functions than other standard libraries,
//   ///      so I can't include demangle.h!
// extern char * cplus_demangle(const char *, int);
}
#include <iomanip>

namespace mrw {
  //----------------------------------------------------------------------------
  static std::string demangle(bfd* abfd, const char* name) {
    if (bfd_get_symbol_leading_char(abfd) == name[0]) ++name;
    
    /* This is a hack for better error reporting on XCOFF, PowerPC64-ELF
       or the MS PE format.  These formats have a number of leading '.'s
       on at least some symbols, so we remove all dots to avoid
       confusing the demangler.  */
    const char* p(name);
    while (p && *p == '.') ++p;
    
    Auto<char*>::Free res(cplus_demangle(p, DMGL_ANSI | DMGL_PARAMS));
    if (res) {
      /* Now put back any stripped dots.  */
      if (p==name) return static_cast<const char*>(res);
      std::string add_dots('.', p-name);
      return add_dots+=static_cast<const char*>(res);
    }
    return name;
  }
}

//----------------------------------------------------------------------------
mrw::StackTrace::StackTrace() throw(std::bad_exception) {
  // maximum trace level is limited here to 50, see below why
#   if defined(__GLIBC__)
  {
    const int TRACE_LEVEL(50);
    void* ba[TRACE_LEVEL];
    for (int n(backtrace(ba, TRACE_LEVEL)), i(0); i<n; ++i)
      _trace.push_back(ba[i]);
  }
#   elif defined(__GNUG__)
  {
#     define push(i)                                                    \
    (__builtin_return_address(i) ?                                      \
     (_trace.push_back(__builtin_return_address(i)), true) : false)
    push(0) && push(1) && push(2) && push(3) && push(4) && push(5) &&
      push(6) && push(7) && push(8) && push(9) && push(10) && push(11) &&
      push(12) && push(13) && push(14) && push(15) && push(16) && push(17)
      && push(18) && push(19) && push(20) && push(21) && push(22) &&
      push(23) && push(24) && push(25) && push(26) && push(27) && push(28)
      && push(29) && push(30) && push(31) && push(32) && push(33) &&
      push(34) && push(35) && push(36) && push(37) && push(38) && push(39)
      && push(40) && push(41) && push(42) && push(43) && push(44) &&
      push(45) && push(46) && push(47) && push(48) && push(49);
#     undef push
  }
#   else
#     warning "You need GNU gcc or GNU glibc to be able to use mrw::StackTrace"
#   endif
}

//----------------------------------------------------------------------------
mrw::StackTrace::operator std::string() const throw(std::bad_exception) {
  static const double LN10(log(10));
  std::string s;
  s<<1;
  bool first(true);
  unsigned int lisz(0), fisz(0);
  std::list<CodePos> l;
  for (AddressTrace::const_reverse_iterator it(_trace.rbegin());
       it!=_trace.rend(); ++it, first=false) {
    CodePos c(translate(*it));
    if (log(c.line+1)/LN10 > lisz) lisz = (unsigned int)(log(c.line+1)/LN10);
    if (c.file.size() > fisz) fisz = c.file.size();
    l.push_back(c);
  }
  for (std::list<CodePos>::iterator it(l.begin()); it!=l.end(); ++it)
    s<<"["<<it->address<<"] "
     <<it->file<<':'<<it->line
     <<std::setw(fisz+lisz-it->file.size()-
                 (unsigned int)(log(it->line+1)/LN10)-1)
     <<" "<<it->function<<"\n";
  return s;
}

//----------------------------------------------------------------------------
const mrw::StackTrace& mrw::StackTrace::print(std::ostream& os) const
  throw(std::bad_exception) {
  os<<(std::string)*this;
  return *this;
}

//----------------------------------------------------------------------------
mrw::StackTrace::CodePos mrw::StackTrace::translate(void* addr)
  throw(std::bad_exception) {
  assert(sizeof(bfd_vma)>=sizeof(void*));
  bfd_vma vma_addr(reinterpret_cast<bfd_vma>(addr));
  std::map<Translator::key_type, std::string>::iterator
    it(_addrs.lower_bound(vma_addr));
  if (it==_addrs.begin() || (--it)->first > vma_addr ||
      _dic.find(it->second)==_dic.end() ||
      _dic[it->second][it->first].first <= vma_addr)
    return CodePos(addr, "????", "????", 0);
  static const char* file(0);
  static const char* function(0);
  unsigned int line;
  if (!bfd_find_nearest_line
      (const_cast<bfd*>(static_cast<const bfd*>(_bfd[it->second])),
       _dic[it->second][it->first].second,
       _syms[it->second],
       vma_addr - it->first,
       &file, &function, &line))
    return CodePos(addr, "????", "????", 0);
  return CodePos(addr, mrw::demangle(_bfd[it->second], function),
                 file?file:"????", line);
}

//----------------------------------------------------------------------------
bool mrw::StackTrace::createSymtable(const std::string& fname, void* offs)
  throw(std::bad_exception) {
  if (_dic.find(fname)!=_dic.end()) return true; // already loaded
  if (fname=="") return createSymtable(filename());
  AutoBfd abfd(bfd_openr(fname.c_str(), 0));
  long memsz(-1);
  Auto<char**>::Free m(0);
  if (!abfd || bfd_check_format(abfd, bfd_archive) ||
      !bfd_check_format_matches(abfd, bfd_object, &(m.getClean())) ||
      !(bfd_get_file_flags(const_cast<bfd*>(static_cast<const bfd*>(abfd)))
        &HAS_SYMS) ||
      (memsz=bfd_get_symtab_upper_bound
       (const_cast<bfd*>(static_cast<const bfd*>(abfd))))<0)
    return false;
  mrw::AutoPtr<asymbol*> syms(new asymbol*[memsz]);
  if (bfd_canonicalize_symtab(const_cast<bfd*>(static_cast<const bfd*>(abfd)),
                              syms)<0)
    return false;
  _bfd[fname] = abfd;
  _syms[fname] = syms;
  _dic[fname];
  std::pair<std::string, void*> fileoffs = std::make_pair(fname, offs);
  bfd_map_over_sections(_bfd[fname], buildSectionMap, &fileoffs);
  return true;
}

//----------------------------------------------------------------------------
bool mrw::StackTrace::createSymtable(const mrw::StackTrace::BinFiles& files)
  throw(std::bad_exception) {
  bool success(true);
  for (BinFiles::const_iterator it(files.begin());
       it!=files.end(); ++it) {
    if (!createSymtable(it->first, it->second)) success=false;
  }
  return success;
}

//----------------------------------------------------------------------------
mrw::StackTrace::BinFiles mrw::StackTrace::filename()
  throw(std::bad_exception) {
  mrw::StackTrace::BinFiles res;
#   if defined(__solaris__)
  {
    std::string s;
    s<<"/proc/"<<getpid();
    AutoFile fd(open(s.str(), O_RDONLY));
    prpsinfo_t status;
    if (fd==-1 || ioctl(fd, PIOCPSINFO, &status)==-1) return res;
    s = status.pr_psargs;
    return res<<BinFiles::value_type(s.substr(0, s.find(' ')), 0);
  }
#   elif defined(__linux__)
  {
    res<<BinFiles::value_type("/proc/self/exe", 0);
    std::ifstream is("/proc/self/maps");
    std::string s;
    std::string range, perm, x1, x2, size, lib;
    while (getline(is, s)) {
      range = perm = x1 = x2 = size = lib = "????";
      s>>range>>perm>>x1>>x2>>size>>lib;
      range.resize(range.find_first_not_of("0123456789abcdefABCDEF"));
      void* addr(0);
      range>>addr;
      if (lib.size() && addr>0) res<<BinFiles::value_type(lib, addr);
    }
    return res;
  }
#   else
  {
#     warning "Don't know how to get executable file name in your system!"
#     warning "Impossible to get function names in stack trace!"
#     warning "Give the path to the executable to StackTrace::createSymtable!"
    return res; // empty
  }
#   endif 
}

//----------------------------------------------------------------------------
void mrw::StackTrace::buildSectionMap(bfd* abfd, asection* section,
                                      void* fileoffs)
  throw(std::bad_exception) {
  if (!abfd || !section || !fileoffs) return;
  if (!(bfd_get_section_flags(abfd, section)&SEC_ALLOC)) return;
  std::pair<std::string, void*> fileoffset =
    *(std::pair<std::string, void*>*)fileoffs;
  bfd_vma vma(bfd_get_section_vma(abfd, section)+
              reinterpret_cast<bfd_vma>(fileoffset.second));
  bfd_size_type sz(bfd_get_section_size_before_reloc(section));
  _dic[fileoffset.first][vma] = Translator::mapped_type(vma+sz, section);
  _addrs[vma] = fileoffset.first;
}

//----------------------------------------------------------------------------
std::map<std::string, mrw::StackTrace::Translator> mrw::StackTrace::_dic;
std::map<mrw::StackTrace::Translator::key_type, std::string>
  mrw::StackTrace::_addrs;
std::map<std::string, mrw::AutoBfd> mrw::StackTrace::_bfd;
std::map<std::string, mrw::AutoPtr<asymbol*> > mrw::StackTrace::_syms;