SealSharedLib.cxx

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/*
  Copyright (C) 2002-2026 CERN for the benefit of the ATLAS collaboration
*/

 
 
#include "CxxUtils/SealCommon.h"               // wlav
#include "CxxUtils/SealSharedLib.h"            // wlav
#include "CxxUtils/SealDebug.h"                // wlav
// wlav copied from SealBase/sysapi/SharedLibrary.h
# ifdef _WIN32
#  include <windows.h>
#  include <winnt.h>
#  include <imagehlp.h>
# else
#  if HAVE_DLOPEN 
#   include <dlfcn.h>
#  elif HAVE_SHL_LOAD
#   include <dl.h>
#  elif HAVE_LOAD
#   include "utils/dlfcn.h"
#  endif
#  if HAVE_LOADER_H
#   include <loader.h>
#  endif
#  if HAVE_LINK_H
#   include <link.h>
#   include <limits.h>
#   include <sys/stat.h>
#   include <unistd.h>
#  endif
#  if HAVE_ELF_H
#   include <elf.h>
#  endif
#  if HAVE_SGIDEFS_H    // irix n32, 64
#   include <sgidefs.h>
#   include <objlist.h>
#   include <obj_list.h>
#   include <obj.h>
#  endif
#  if HAVE_MACH_O_DYLD_H // darwin
#   include <mach-o/dyld.h>
#   include <mach-o/getsect.h>
#  endif
# endif // _WIN32
# include <cstring>
# include <cstdio>
# include <cstdlib>
# include <errno.h>
 
#include <assert.h>                            // wlav
#include <bit>
 
#ifndef HAVE_R_DEBUG
   extern ElfW(Dyn) _DYNAMIC []; // #pragma weak?   // wlav
#endif
 
//namespace seal {                                wlav
namespace Athena {                             // wlav
 
#ifndef SHLIB_UNSUPPORTED
# define  SHLIB_UNSUPPORTED \
    throw SharedLibraryError ("", "unsupported operation")
#endif
 
 
// wlav modified from SealBase/src/SharedLibraryError.cpp
SharedLibraryError::SharedLibraryError (const std::string& context,
                    const std::string& cause)
  : m_message ("Shared library operation")
{
  if (! context.empty ())
  {
    m_message += " ";
    m_message += context;
  }
 
  m_message += " failed";
 
  if (! cause.empty ())
  {
    m_message += " because: ";
    m_message += cause;
  }
}
 
const char*
SharedLibraryError::what() const throw()
{
  return m_message.c_str();
}
 
 
// wlav continued from SealBase/src/SharedLibrary.cpp
#ifdef _WIN32
static BOOL CALLBACK
enumModules (LPSTR name, ULONG base_address, PVOID context)
{
    IMAGEHLP_MODULE          moduleinfo;
    const SharedLibrary::InfoHandler    *handler
    = static_cast<SharedLibrary::InfoHandler *> (context);
 
    memset (&moduleinfo, 0, sizeof (moduleinfo));
    moduleinfo.SizeOfStruct = sizeof (moduleinfo);
 
    SharedLibrary::LibraryInfo info;
 
    if (SymGetModuleInfo (GetCurrentProcess (), base_address, &moduleinfo))
    {
    info.m_filename   = moduleinfo.LoadedImageName;
    info.m_text_start = moduleinfo.BaseOfImage;
    info.m_text_end   = moduleinfo.BaseOfImage + moduleinfo.ImageSize;
    info.m_data_start = 0;
    info.m_data_end   = 0;
    info.m_bss_start  = 0;
    info.m_bss_end    = 0;
    }
    else
    {
    info.m_filename   = name;
    info.m_text_start = base_address;
    info.m_text_end   = 0;
    info.m_data_start = 0;
    info.m_data_end   = 0;
    info.m_bss_start  = 0;
    info.m_bss_end    = 0;
    }
    (*handler) (info);
    return TRUE;
}
#endif
 
 
std::string
SharedLibrary::path (void)
{
    const char *pathvar = PATH;
    const char *path = pathvar ? getenv (pathvar) : 0;
    return path ? path : "";
}
 
void
SharedLibrary::path ATLAS_NOT_THREAD_SAFE (const std::string &path)
{
    /* Do not free `var'; most implementations of `putenv' use the
       string without copying it.  On systems where `putenv' copies,
       you'll see leaks from this routine.  It would be possible to
       check for this, but only by killing cross-compilation.
 
       NB: `HAVE_COPYING_PUTENV' will never be set as we are not
       checking for it :-)  */
 
    const char *pathvar = PATH;
    if (pathvar) {
        setenv(pathvar, path.c_str(),1);
    }
}

std::string
SharedLibrary::libname (const std::string &name)
{
#ifdef _WIN32
    return name + ".dll";
#elif defined __hpux
    return "lib" + name + ".sl";
#else
    return "lib" + name + ".so";
#endif
}

std::string
SharedLibrary::symname (const std::string &name)
{ return name; }


SharedLibrary *
SharedLibrary::self (void)
{
#if HAVE_DLOPEN || HAVE_LOAD
    // NB: Linux (at least RH 7.x) dynamic loader is severely broken
    // when it comes to reporting error messages.  The error messages
    // are frequently garbled or null.  If you see a crash in a call
    // to dlerror(), sorry, there's nothing we can do about that.
    // Our attempts have only produced even more undesirable crashes.
    // Waiting for a better version of the linux dynamic loader.
    void *handle = ::dlopen (0, RTLD_LAZY);
    if (! handle)
    {
    const char *msg = ::dlerror ();
    msg = msg ? msg : "dynamic linker error message lost!";
    throw SharedLibraryError ("dlopen()", msg);
    }
 
    return new SharedLibrary (handle);
#elif HAVE_SHL_LOAD
    return new SharedLibrary (PROG_HANDLE);
#elif defined _WIN32
    return new SharedLibrary (::GetModuleHandle (0));
#else
    SHLIB_UNSUPPORTED;
#endif
}

SharedLibrary *
SharedLibrary::load (const std::string &name)
{
    assert(! name.empty ());
 
    void *handle = 0;
 
#if HAVE_DLOPEN || HAVE_LOAD
# ifndef RTLD_GLOBAL
#  define RTLD_GLOBAL 0
# endif
    // See comments in "self()" about crashes in dlerror().
    if (! (handle = ::dlopen (name.c_str (), RTLD_LAZY | RTLD_GLOBAL)))
    {
    const char *msg = ::dlerror ();
    msg = msg ? msg : "dynamic linker error message lost!";
    throw SharedLibraryError ("dlopen()", msg);
    }
 
#elif HAVE_SHL_LOAD
    if (! (handle = ::shl_load (name.c_str (), BIND_DEFERRED, 0L)))
    throw SharedLibraryError ("shl_load()", errno);
 
#elif defined _WIN32
    if (! (handle = ::LoadLibrary (name.c_str ())))
    throw SharedLibraryError ("LoadLibrary()", GetLastError ());
#else
    SHLIB_UNSUPPORTED;
#endif
 
    return new SharedLibrary (handle);
}

void
SharedLibrary::loaded (InfoHandler &handler)
{
    // Dynamic linker characteristics:
    //   AIX, Windows, SVR4 (DG/UX, DRS/NX, DYNIX/ptx, Linux, SINIX,
    //   Solaris, UnixWare, {Free,Open,Net}BSD if __ELF__), BSD,
    //   HP-UX, IRIX, Tru64
 
    // Object file formats:
    //   XCOFF (AIX), ELF32/64 (DG/UX, DRS/NX, DYNIX/ptx, IRIX, SINIX,
    //   Solaris, UnixWare, {Free,Open,Net}BSD: if __ELF__), a.out
    //   ({Free,Open,Net}BSD if ! __ELF__, SunOS), BFD (Cygwin, HP-UX,
    //   Linux, LynxOS, Tru64, Windows if GCC), PE (Windows), COFF (?)
 
#if HAVE_SHL_LOAD                   // hp-ux
    shl_descriptor desc;
 
    for (int index = -1; shl_get_r (index, &desc) == 0; ++index)
    {
    LibraryInfo info;
    info.m_filename   = desc.filename;
    info.m_text_start = desc.tstart;
    info.m_text_end   = desc.tend;
    info.m_data_start = desc.dstart;
    info.m_data_end   = desc.dend;
    info.m_bss_start  = 0;
    info.m_bss_end    = 0;
 
    handler (info);
    }
 
#elif HAVE_LINK_H                   // bsd/svr4/elf
# if !HAVE_LINK_MAP_L_MAP_START
#  define l_map_start l_addr
#  define l_map_end   l_addr
# endif
# if !HAVE_PROGRAM_INVOCATION_NAME
    static const char *program_invocation_name = "(unknown program name)";
# endif
# if HAVE_R_DEBUG                   // linux/glibc
    link_map *p = _r_debug.r_map;
# else
    // Dynamic linker root:
    //   BSD (SunOS):
    //     #include <sys/types.h>
    //     #include <link.h>
    //     extern struct link_dynamic _DYNAMIC;
    //     link_dynamic *d = &_DYNAMIC;
    //     if ((d->ld_version > 1) && (d->ld_version <= 3) && (d->ld_un.ld_1 != 0))
    //       --> link_map *l = d->ld_un.ld_1->ld_loaded
    //          l->lm_name, l->lm_addr, l->lm_next
    //
    //   BSD ({Free,Open,Net}BSD):
    //     #include <sys/types.h>
    //     #include <link.h>
    //     extern struct _dynamic _DYNAMIC
    //     _dynamic *d = &_DYNAMIC;
    //     if ((d->version == LD_VERSION_BSD) && d->d_un.d_sdt != 0))
    //       --> so_map *l = d->d_un.d_sdt->sdt_loaded
    //           l->som_path, l->som_addr, l->som_next
    //
    //   SVR4 (DG/UX, DRS/NX, DYNIX/ptx, SINIX, UnixWare)
    //     ElfW(Dyn) _DYNAMIC[]  // Linux
    //     void _DYNAMIC (void)  // weak, really is data, but not
    //                           // all compilers allow weak data
    //
    //   Solaris:
    //     dlinfo (self, RTLD_DI_LINKMAP, &p);
 
 //    extern ElfW(Dyn) _DYNAMIC []; // #pragma weak?  // wlav
    link_map *p = 0;
    for (ElfW(Dyn) *dyn = _DYNAMIC; dyn->d_tag != DT_NULL; ++dyn)
    if (dyn->d_tag == DT_DEBUG && dyn->d_un.d_ptr)
        // linux: p = ((r_debug *) dyn->d_un_d.ptr)->r_map;
        p = (link_map *) *((unsigned long *) dyn->d_un.d_ptr + 1);
# endif
 
    if (! p)
       throw SharedLibraryError ("loaded", "no shared library load map");
 
    // Get executable name; linux has a symlink in /proc/self/exe.
    // Linux path names are arbitrarily long, so we just have create
    // some random-sized buffer.  We allocate this on stack to avoid
    // dynamic memory allocation.  If this is a problem, report a bug.
    struct stat sbuf;
    char    exe [4096];
 
    memset (exe, 0, sizeof (exe));
    if (::stat ("/proc/self/exe", &sbuf) == 0)
    ::readlink ("/proc/self/exe", exe, sizeof (exe)-1);
    else
       STDC::strncpy (exe, program_invocation_name, sizeof (exe)-1);
 
    // Get shared libraries
    for ( ; p; p = p->l_next)
    {
    LibraryInfo info;
 
    /* FIXME: Does this work with prelinked shared libraries?
       From a mail to GCC mailing list ("fde-glibc.c bug"):
 
         There is a bug in gcc/config/ia64/fde-glibc.c:
         ret = find_fde_for_dso ((Elf64_Addr)pc, (Elf64_Ehdr *)map->l_addr,
                                       ^^^^^^^^^^^
                     segment_base, gp);
 
         this will work only as long as the shared library in
         question has first PT_LOAD segment's p_vaddr == 0.
         E.g. with ELF prelinking this is almost never true
         though, so what you really want is map->l_map_start
         (map->l_addr will be almost always 0) or even better
         map->l_phdr/map->l_phnum pair.  */
 
    // FIXME: use the map address (= ElfW(Ehdr)) to scan over
    // the different ElfW(Phdr)s to find the various sections.
    info.m_filename   = (p->l_name && p->l_name[0] ? p->l_name : exe);
    info.m_text_start = p->l_addr ? p->l_addr : p->l_map_start;
    info.m_text_end   = p->l_addr ? p->l_addr : p->l_map_end;
    info.m_data_start = 0;
    info.m_data_end   = 0;
    info.m_bss_start  = 0;
    info.m_bss_end    = 0;
 
    handler (info);
    }
 
#elif HAVE_SGIDEFS_H                    // irix
    /* From rld(1) man page:
 
       rld keeps a doubly linked list of structures and crt1.o
       contains a pointer to the head of the list of obj structures
       called __rld_obj_head. In an o32 executable, this points to a
       linked list of objList structures (/usr/include/obj_list.h),
       each of which has a `data' element which is a pointer to a
       `struct obj' (/usr/include/obj.h) (even though the field is not
       declared as a pointer). In an n32 executable, __rld_obj_head
       points to a linked list of Elf32_Obj_Info structures
       (/usr/include/objlist.h).  In a 64-bit executable,
       __rld_obj_head points to a linked list of Elf64_Obj_Info
       structures (/usr/include/objlist.h).  The `oi_magic' element of
       each Elf32_Obj_Info or Elf64_Obj_Info is all-bits-on
       (0xffffffff) to make it easier to determine which list type is
       in use a 32-bit executable.  */
 
    // To get more details by reading the ELF files:
    // http://reality.sgi.com/davea/software.html
    extern ElfW(Obj_Info)   *__rld_obj_head;
    ElfW(Obj_Info)      *p = __rld_obj_head;
 
    for ( ; p; p = (ElfW(Obj_Info) *) p->oi_next)
    {
    LibraryInfo info;
 
# if defined _MIPS_SIM_ABI32 && _MIPS_SIM == _MIPS_SIM_ABI32
    info.m_filename   = (const char *) p->o_path;
    info.m_text_start = p->o_praw;  // base address: o_base_address
    info.m_text_end   = p->o_praw;
# elif (defined _MIPS_SIM_NABI32 && _MIPS_SIM == _MIPS_SIM_NABI32) \
    || (defined _MIPS_SIM_ABI64  && _MIPS_SIM == _MIPS_SIM_ABI64)
    info.m_filename   = (const char *) p->oi_pathname;
    info.m_text_start = p->oi_ehdr; // base address: oi_orig_ehdr
    info.m_text_end   = p->oi_ehdr;
# else
#  error "Unsupported ABI: not o32, n32 or 64"
# endif
    info.m_data_start = 0;
    info.m_data_end   = 0;
    info.m_bss_start  = 0;
    info.m_bss_end    = 0;
 
    handler (info);
    }
 
#elif HAVE_LOADER_H && HAVE_LDR_NEXT_MODULE_DECL    // tru64
    ldr_process_t   proc = ldr_my_process ();
    ldr_module_t    mod  = LDR_NULL_MODULE;
    int         ret  = ldr_next_module (proc, &mod);
 
    for (; ret == 0 && mod != LDR_NULL_MODULE; ret = ldr_next_module (proc, &mod))
    {
    ldr_module_info_t   info;
    size_t          size = 0;
    LibraryInfo     libinfo;
 
    if (ldr_inq_module(proc, mod, &info, sizeof(info), &size) < 0)
        throw SharedLibraryError ("ldr_inq_module()", errno);
 
    libinfo.m_filename   = info.lmi_name;
    libinfo.m_text_start = 0;
    libinfo.m_text_end   = 0;
    libinfo.m_data_start = 0;
    libinfo.m_data_end   = 0;
    libinfo.m_bss_start  = 0;
    libinfo.m_bss_end    = 0;
 
    for (int i = 0; i < info.lmi_nregion; ++i)
    {
        ldr_region_info_t   rinfo;
        unsigned long   low;
        unsigned long   high;
 
        if (ldr_inq_region(proc, mod, i, &rinfo, sizeof(rinfo), &size) < 0)
            throw SharedLibraryError ("ldr_inq_region()", errno);
 
        low  = (unsigned long) rinfo.lri_mapaddr;
        high = ((unsigned long) rinfo.lri_mapaddr) + rinfo.lri_size;
 
        if (!strcmp(rinfo.lri_name, ".text")) {
        libinfo.m_text_start = low;
        libinfo.m_text_end   = high;
        } else if (!strcmp(rinfo.lri_name, ".data")) {
        libinfo.m_data_start = low;
        libinfo.m_data_end   = high;
        } else if (!strcmp(rinfo.lri_name, ".bss")) {
        libinfo.m_bss_start  = low;
        libinfo.m_bss_end    = high;
        }
    }
 
    handler (libinfo);
    }
 
    if (ret < 0)
    throw SharedLibraryError ("ldr_next_module()", errno);
 
#elif HAVE_LOAD && HAVE_LOAD_DECL           // aix
    int     size = 16;
    void    *buffer = new ld_info [size];
    int     error = ::loadquery (L_GETINFO, buffer, size);
    int     offset = 0;
 
    while (error == -1 && errno == ENOMEM)
    {
    delete [] (ld_info *) buffer;
    buffer = new ld_info [size *= 2];
    error = ::loadquery (L_GETINFO, buffer, size);
    }
 
    if (error == -1)
    throw SharedLibraryError ("loadquery()", errno);
 
    while (true)
    {
    LibraryInfo info;
    ld_info     *ld = (ld_info *) ((char *) buffer + offset);
    const char  *path = ld->ldinfo_filename;
    const char  *member = path + strlen (path) + 1;
    std::string filename;   // FIXME: Use alloca instead?
 
    filename = path;
    if (*member)
    {
        filename += '(';
        filename += member;
        filename += ')';
    }
 
    info.m_filename   = filename.c_str ();
    info.m_text_start = (unsigned long) ld->ldinfo_textorg;
    info.m_text_end   = info.m_text_start + ld->ldinfo_textsize;
    info.m_data_start = (unsigned long) ld->ldinfo_dataorg;
    info.m_data_end   = info.m_data_start + ld->ldinfo_datasize;
    info.m_bss_start  = 0;
    info.m_bss_end    = 0;
 
    handler (info);
 
    if (ld->ldinfo_next)
        offset += ld->ldinfo_next;
    else
        break;
    }
 
    delete [] (ld_info *) buffer;
 
#elif HAVE_MACH_O_DYLD_H                // darwin
    unsigned long images = _dyld_image_count ();
    for (unsigned long i = 0; i < images; ++i)
    {
    const mach_header *hdr = _dyld_get_image_header (i);
    unsigned long    slide = _dyld_get_image_vmaddr_slide (i);
    unsigned int    size;
    char        *sect;
    LibraryInfo info;
 
    info.m_filename   = _dyld_get_image_name (i);
 
    sect = getsectdatafromheader (hdr, SEG_TEXT, SECT_TEXT, &size);
    info.m_text_start = sect ? (unsigned long) sect + slide : 0;
    info.m_text_end   = sect ? (unsigned long) sect + slide + size : 0;
    sect = getsectdatafromheader (hdr, SEG_DATA, SECT_DATA, &size);
    info.m_data_start = sect ? (unsigned long) sect + slide : 0;
    info.m_data_end   = sect ? (unsigned long) sect + slide + size : 0;
    sect = getsectdatafromheader (hdr, SEG_DATA, SECT_BSS, &size);
    info.m_bss_start  = sect ? (unsigned long) sect + slide : 0;
    info.m_bss_end    = sect ? (unsigned long) sect + slide + size : 0;
 
    handler (info);
    }
 
#elif defined _WIN32                    // windows
    if (! SymInitialize (GetCurrentProcess (), NULL, TRUE)
    || ! SymEnumerateModules (GetCurrentProcess (), &enumModules, (void *) &handler)
    || ! SymCleanup (GetCurrentProcess ()))
    throw SharedLibraryError ("SymEnumerateModules()", GetLastError());
#else
    SHLIB_UNSUPPORTED;
#endif
}

SharedLibrary::SharedLibrary (void *handle)
    : m_handle (handle)
{ assert (m_handle); }

SharedLibrary::~SharedLibrary (void)
{ assert (! m_handle); }

void
SharedLibrary::release (void)
{
    assert (m_handle);
 
#if HAVE_DLOPEN || HAVE_LOAD
    ::dlclose (m_handle);
#elif HAVE_SHL_LOAD
    ::shl_unload ((shl_t) m_handle);
#elif defined _WIN32
    ::FreeLibrary ((HINSTANCE) m_handle);
#else
    // cannot get here---`load' and `self' should take care of it.
    assert (false);
#endif
 
    m_handle = 0;
    delete this;
}

void
SharedLibrary::abandon (void)
{
    assert (m_handle);
    m_handle = 0;
    delete this;
}

SharedLibrary::Data
SharedLibrary::data (const std::string &name, bool mangle /* = true */) const
{
    assert (! name.empty ());
    assert (m_handle);
    std::string mangled = mangle ? symname (name) : name;
    Data    symbol = 0;
 
#if HAVE_DLOPEN || HAVE_LOAD
    // See comments in "self()" about crashes in dlerror().
    const char *error = 0;
    symbol = ::dlsym (m_handle, mangled.c_str ());
    if (! symbol && (error = ::dlerror ()) != 0)
    throw SharedLibraryError ("dlsym()", error);
 
#elif HAVE_SHL_LOAD
    shl_t handle = (shl_t) m_handle;
    if (::shl_findsym (&handle, mangled.c_str (), TYPE_DATA, &symbol) != 0)
    throw SharedLibraryError ("shl_findsym()", errno);
    assert (handle == (shl_t) m_handle);
 
#elif defined _WIN32
    if (! (symbol = (Data)::GetProcAddress((HINSTANCE)m_handle, mangled.c_str())))
    throw SharedLibraryError ("GetProcAddress()", GetLastError ());
#else
    // cannot get here---`load' and `self' should take care of it.
    assert (false);
#endif
    return symbol;
}

SharedLibrary::Function
SharedLibrary::function (const std::string &name, bool mangle /* = true */) const
{
    assert (! name.empty ());
    assert (m_handle);
    std::string mangled = mangle ? symname (name) : name;
    Function    symbol = 0;
 
#if HAVE_DLOPEN || HAVE_LOAD
    // See comments in "self()" about crashes in dlerror().
    static_assert (sizeof (Function) == sizeof (Data));
    const char *error = 0;
    Data data = ::dlsym (m_handle, mangled.c_str ());
    if (! data && (error = ::dlerror ()) != 0) throw SharedLibraryError ("dlsym()", error);
    symbol = std::bit_cast<Function> (data);
 
#elif HAVE_SHL_LOAD
    shl_t handle = (shl_t) m_handle;
    if (::shl_findsym (&handle, mangled.c_str (), TYPE_PROCEDURE, &symbol) != 0)
    throw SharedLibraryError ("shl_findsym()", errno);
    assert (handle == (shl_t) m_handle);
 
#elif defined _WIN32
    if (! (symbol = (Function) ::GetProcAddress ((HINSTANCE) m_handle,
                         mangled.c_str ())))
    throw SharedLibraryError ("GetProcAddress()", GetLastError ());
#else
    // cannot get here---`load' and `self' should take care of it.
    assert (false);
#endif
    return symbol;
}
 
//} // namespace seal                             wlav
} // namespace Athena                             wlav