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// Copyright (C) 2011 Internet Systems Consortium, Inc. ("ISC")
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
// copyright notice and this permission notice appear in all copies.
//
// THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
// AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
// OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
// PERFORMANCE OF THIS SOFTWARE.
#include "factory.h"
#include "exceptions.h"
#include "database.h"
#include "sqlite3_accessor.h"
#include "datasrc_config.h"
#include <datasrc/logger.h>
#include <exceptions/exceptions.h>
#include <dlfcn.h>
#include <cstdlib>
using namespace std;
using namespace isc::data;
using namespace isc::datasrc;
namespace {
// This helper function takes the 'type' string as passed to
// the DataSourceClient container below, and, unless it
// already specifies a specific loadable .so file, will
// convert the short-name to the full file.
// I.e. it will add '_ds.so' (if necessary), and prepend
// it with an absolute path (if necessary).
// Returns the resulting string to use with LibraryContainer.
const std::string
getDataSourceLibFile(const std::string& type) {
if (type.empty()) {
isc_throw(DataSourceLibraryError,
"DataSourceClient container called with empty type value");
}
if (type == ".so") {
isc_throw(DataSourceLibraryError, "DataSourceClient container called "
"with bad type or file name");
}
// Type can be either a short name, in which case we need to
// append "_ds.so", or it can be a direct .so library.
std::string lib_file = type;
const int ext_pos = lib_file.rfind(".so");
if (ext_pos == std::string::npos || ext_pos + 3 != lib_file.length()) {
lib_file.append("_ds.so");
}
// And if it is not an absolute path, prepend it with our
// loadable backend library path
if (type[0] != '/') {
// When running from the build tree, we do NOT want
// to load the installed loadable library
if (getenv("B10_FROM_BUILD") != NULL) {
lib_file = std::string(getenv("B10_FROM_BUILD")) +
"/src/lib/datasrc/.libs/" + lib_file;
} else {
lib_file = isc::datasrc::BACKEND_LIBRARY_PATH + lib_file;
}
}
return (lib_file);
}
} // end anonymous namespace
namespace isc {
namespace datasrc {
LibraryContainer::LibraryContainer(const std::string& name) {
// use RTLD_GLOBAL so that shared symbols (e.g. exceptions)
// are recognized as such
ds_lib_ = dlopen(name.c_str(), RTLD_NOW | RTLD_GLOBAL);
if (ds_lib_ == NULL) {
// This may cause the filename to appear twice in the actual
// error, but the output of dlerror is implementation-dependent
isc_throw(DataSourceLibraryError, "dlopen failed for " << name <<
": " << dlerror());
}
}
LibraryContainer::~LibraryContainer() {
dlclose(ds_lib_);
}
void*
LibraryContainer::getSym(const char* name) {
// Since dlsym can return NULL on success, we check for errors by
// first clearing any existing errors with dlerror(), then calling dlsym,
// and finally checking for errors with dlerror()
dlerror();
void *sym = dlsym(ds_lib_, name);
const char* dlsym_error = dlerror();
if (dlsym_error != NULL) {
isc_throw(DataSourceLibrarySymbolError, dlsym_error);
}
return (sym);
}
DataSourceClientContainer::DataSourceClientContainer(const std::string& type,
ConstElementPtr config)
: ds_lib_(getDataSourceLibFile(type))
{
// We are casting from a data to a function pointer here
// Some compilers (rightfully) complain about that, but
// c-style casts are accepted the most here. If we run
// into any that also don't like this, we might need to
// use some form of union cast or memory copy to get
// from the void* to the function pointer.
ds_creator* ds_create = (ds_creator*)ds_lib_.getSym("createInstance");
destructor_ = (ds_destructor*)ds_lib_.getSym("destroyInstance");
std::string error;
try {
instance_ = ds_create(config, error);
if (instance_ == NULL) {
isc_throw(DataSourceError, error);
}
} catch (const std::exception& exc) {
isc_throw(DataSourceError, "Unknown uncaught exception from " + type +
" createInstance: " + exc.what());
} catch (...) {
isc_throw(DataSourceError, "Unknown uncaught exception from " + type);
}
}
DataSourceClientContainer::~DataSourceClientContainer() {
destructor_(instance_);
}
} // end namespace datasrc
} // end namespace isc
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