From: Gabriel Corona <gabriel.corona@loria.fr>
Date: Mon, 18 Apr 2016 12:53:48 +0000 (+0200)
Subject: Clear errno when throwing an errno exception
X-Git-Tag: v3_13~73
X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/commitdiff_plain/4bd2cbe6c40e96efdbf49550cc66bb9e35df8b94

Clear errno when throwing an errno exception
---

diff --git a/include/xbt/system_error.hpp b/include/xbt/system_error.hpp
index 4a2ae7ae44..4b0bbf21fd 100644
--- a/include/xbt/system_error.hpp
+++ b/include/xbt/system_error.hpp
@@ -43,6 +43,15 @@ std::error_code errno_code(int errnum)
   return std::error_code(errnum, errno_category());
 }
 
+/** Create an `error_code` from `errno` (and clear it) */
+inline
+std::error_code errno_code()
+{
+  int errnum = errno;
+  errno = 0;
+  return errno_code(errnum);
+}
+
 /** Create a `system_error` from an `errno` value
  *
  *  This is expected to to whatever is right to create a
@@ -60,6 +69,19 @@ std::system_error errno_error(int errnum, const char* what)
   return std::system_error(errno_code(errnum), what);
 }
 
+/** Create a `system_code` from `errno` (and clear it) */
+inline
+std::system_error errno_error()
+{
+  return std::system_error(errno_code());
+}
+
+inline
+std::system_error errno_error(const char* what)
+{
+  return std::system_error(errno_code(), what);
+}
+
 }
 }
 
diff --git a/src/mc/ModelChecker.cpp b/src/mc/ModelChecker.cpp
index 0b7eadf16a..956f5f13d1 100644
--- a/src/mc/ModelChecker.cpp
+++ b/src/mc/ModelChecker.cpp
@@ -82,7 +82,7 @@ void ModelChecker::start()
   sigemptyset(&set);
   sigaddset(&set, SIGCHLD);
   if (sigprocmask(SIG_BLOCK, &set, nullptr) == -1)
-    throw simgrid::xbt::errno_error(errno);
+    throw simgrid::xbt::errno_error();
 
   sigset_t full_set;
   sigfillset(&full_set);
@@ -96,7 +96,7 @@ void ModelChecker::start()
 
   int signal_fd = signalfd(-1, &set, 0);
   if (signal_fd == -1)
-    throw simgrid::xbt::errno_error(errno);
+    throw simgrid::xbt::errno_error();
 
   struct pollfd* signalfd_pollfd = &fds_[SIGNAL_FD_INDEX];
   signalfd_pollfd->fd = signal_fd;
@@ -170,7 +170,7 @@ void ModelChecker::resume(simgrid::mc::Process& process)
 {
   int res = process.getChannel().send(MC_MESSAGE_CONTINUE);
   if (res)
-    throw simgrid::xbt::errno_error(res);
+    throw simgrid::xbt::errno_error();
   process.clear_cache();
 }
 
@@ -181,7 +181,7 @@ void throw_socket_error(int fd)
   socklen_t errlen = sizeof(error);
   if (getsockopt(fd, SOL_SOCKET, SO_ERROR, (void *)&error, &errlen) == -1)
     error = errno;
-  throw simgrid::xbt::errno_error(errno);
+  throw simgrid::xbt::errno_error();
 }
 
 static void MC_report_crash(int status)
@@ -333,7 +333,7 @@ bool ModelChecker::handle_events()
     case EINTR:
       continue;
     default:
-      throw simgrid::xbt::errno_error(errno);
+      throw simgrid::xbt::errno_error();
     }
   }
 
@@ -341,7 +341,7 @@ bool ModelChecker::handle_events()
     if (socket_pollfd->revents & POLLIN) {
       ssize_t size = process_->getChannel().receive(buffer, sizeof(buffer), false);
       if (size == -1 && errno != EAGAIN)
-        throw simgrid::xbt::errno_error(errno);
+        throw simgrid::xbt::errno_error();
       return handle_message(buffer, size);
     }
     if (socket_pollfd->revents & POLLERR)
@@ -380,7 +380,7 @@ void ModelChecker::handle_signals()
       if (errno == EINTR)
         continue;
       else
-        throw simgrid::xbt::errno_error(errno);
+        throw simgrid::xbt::errno_error();
     } else if (size != sizeof(info))
         return throw std::runtime_error(
           "Bad communication with model-checked application");
@@ -405,7 +405,7 @@ void ModelChecker::handle_waitpid()
           break;
       } else {
         XBT_ERROR("Could not wait for pid");
-        throw simgrid::xbt::errno_error(errno);
+        throw simgrid::xbt::errno_error();
       }
     }
 
diff --git a/src/mc/Session.cpp b/src/mc/Session.cpp
index 99696652ab..095d4b05dc 100644
--- a/src/mc/Session.cpp
+++ b/src/mc/Session.cpp
@@ -32,9 +32,9 @@ static void setup_child_environment(int socket)
   sigset_t mask;
   sigemptyset (&mask);
   if (sigprocmask(SIG_SETMASK, &mask, nullptr) < 0)
-    throw simgrid::xbt::errno_error(errno, "Could not unblock signals");
+    throw simgrid::xbt::errno_error("Could not unblock signals");
   if (prctl(PR_SET_PDEATHSIG, SIGHUP) != 0)
-    throw simgrid::xbt::errno_error(errno, "Could not PR_SET_PDEATHSIG");
+    throw simgrid::xbt::errno_error("Could not PR_SET_PDEATHSIG");
 #endif
 
   int res;
@@ -42,7 +42,7 @@ static void setup_child_environment(int socket)
   // Remove CLOEXEC in order to pass the socket to the exec-ed program:
   int fdflags = fcntl(socket, F_GETFD, 0);
   if (fdflags == -1 || fcntl(socket, F_SETFD, fdflags & ~FD_CLOEXEC) == -1)
-    throw simgrid::xbt::errno_error(errno, "Could not remove CLOEXEC for socket");
+    throw simgrid::xbt::errno_error("Could not remove CLOEXEC for socket");
 
   // Set environment:
   setenv(MC_ENV_VARIABLE, "1", 1);
@@ -66,7 +66,7 @@ pid_t do_fork(F code)
 {
   pid_t pid = fork();
   if (pid < 0)
-    throw simgrid::xbt::errno_error(errno, "Could not fork model-checked process");
+    throw simgrid::xbt::errno_error("Could not fork model-checked process");
   if (pid != 0)
     return pid;
 
@@ -141,7 +141,7 @@ Session* Session::fork(std::function<void(void)> code)
   int sockets[2];
   res = socketpair(AF_LOCAL, SOCK_DGRAM | SOCK_CLOEXEC, 0, sockets);
   if (res == -1)
-    throw simgrid::xbt::errno_error(errno, "Could not create socketpair");
+    throw simgrid::xbt::errno_error("Could not create socketpair");
 
   pid_t pid = do_fork([&] {
     ::close(sockets[1]);