* Set a terminate() handler to ensure that we leave the BDB

environment cleanly even when an exception is thrown from a
  destructor.  We still crash, but we don't take all other Nix
  processes with us.
This commit is contained in:
Eelco Dolstra 2007-05-01 15:16:17 +00:00
parent 644946feed
commit cbfac2fdcc
6 changed files with 55 additions and 8 deletions

View file

@ -7,6 +7,7 @@
#include <iostream>
#include <cctype>
#include <exception>
#include <sys/stat.h>
#include <unistd.h>
@ -81,6 +82,23 @@ struct RemoveTempRoots
void initDerivationsHelpers();
static void closeStore()
{
try {
throw;
} catch (std::exception & e) {
printMsg(lvlError,
format("FATAL: unexpected exception (closing store and aborting): %1%") % e.what());
}
try {
store.reset((StoreAPI *) 0);
} catch (...) {
ignoreException();
}
abort();
}
/* Initialize and reorder arguments, then call the actual argument
processor. */
static void initAndRun(int argc, char * * argv)
@ -195,6 +213,12 @@ static void initAndRun(int argc, char * * argv)
exit. */
RemoveTempRoots removeTempRoots; /* unused variable - don't remove */
/* Make sure that the database gets closed properly, even if
terminate() is called (which happens sometimes due to bugs in
destructor/exceptions interaction, but that needn't preclude a
clean shutdown of the database). */
std::set_terminate(closeStore);
run(remaining);
/* Close the Nix database. */

View file

@ -685,8 +685,8 @@ DerivationGoal::~DerivationGoal()
try {
killChild();
deleteTmpDir(false);
} catch (Error & e) {
printMsg(lvlError, format("error (ignored): %1%") % e.msg());
} catch (...) {
ignoreException();
}
}

View file

@ -161,7 +161,11 @@ LocalStore::LocalStore(bool reserveSpace)
LocalStore::~LocalStore()
{
/* If the database isn't open, this is a NOP. */
nixDB.close();
try {
nixDB.close();
} catch (...) {
ignoreException();
}
}

View file

@ -148,8 +148,8 @@ RemoteStore::~RemoteStore()
fdSocket.close();
if (child != -1)
child.wait(true);
} catch (Error & e) {
printMsg(lvlError, format("error (ignored): %1%") % e.msg());
} catch (...) {
ignoreException();
}
}

View file

@ -444,7 +444,11 @@ void warnOnce(bool & haveWarned, const format & f)
static void defaultWriteToStderr(const unsigned char * buf, size_t count)
{
writeFull(STDERR_FILENO, buf, count);
try {
writeFull(STDERR_FILENO, buf, count);
} catch (SysError & e) {
/* ignore EPIPE etc. */
}
}
@ -545,8 +549,8 @@ AutoCloseFD::~AutoCloseFD()
{
try {
close();
} catch (Error & e) {
printMsg(lvlError, format("error (ignored): %1%") % e.msg());
} catch (...) {
ignoreException();
}
}
@ -968,5 +972,15 @@ bool string2Int(const string & s, int & n)
return str && str.get() == EOF;
}
void ignoreException()
{
try {
throw;
} catch (std::exception & e) {
printMsg(lvlError, format("error (ignored): %1%") % e.what());
}
}
}

View file

@ -280,6 +280,11 @@ string int2String(int n);
bool string2Int(const string & s, int & n);
/* Exception handling in destructors: print an error message, then
ignore the exception. */
void ignoreException();
}