Imported from /home/lorry/working-area/delta_boost-tarball/boost_1_58_0.tar.bz2.HEADboost_1_58_0master

1 files changed, 42 insertions, 2 deletions

diff --git a/tools/build/src/engine/execunix.c b/tools/build/src/engine/execunix.c
index 965e58011..297c00377 100644
--- a/tools/build/src/engine/execunix.c
+++ b/tools/build/src/engine/execunix.c
@@ -137,6 +137,9 @@ void exec_cmd
     LIST * shell
 )
 {
+    struct sigaction ignore, saveintr, savequit;
+    sigset_t chldmask, savemask;
+
     int const slot = get_free_cmdtab_slot();
     int out[ 2 ];
     int err[ 2 ];
@@ -203,6 +206,21 @@ void exec_cmd
     if ( globs.pipe_action )
         fcntl( err[ EXECCMD_PIPE_READ ], F_SETFD, FD_CLOEXEC );
 
+    /* ignore SIGINT and SIGQUIT */
+    ignore.sa_handler = SIG_IGN;
+    sigemptyset(&ignore.sa_mask);
+    ignore.sa_flags = 0;
+    if (sigaction(SIGINT, &ignore, &saveintr) < 0)
+        return;
+    if (sigaction(SIGQUIT, &ignore, &savequit) < 0)
+        return;
+
+    /* block SIGCHLD */
+    sigemptyset(&chldmask);
+    sigaddset(&chldmask, SIGCHLD);
+    if (sigprocmask(SIG_BLOCK, &chldmask, &savemask) < 0)
+        return;
+
     if ( ( cmdtab[ slot ].pid = vfork() ) == -1 )
     {
         perror( "vfork" );
@@ -216,6 +234,11 @@ void exec_cmd
         /*****************/
         int const pid = getpid();
 
+        /* restore previous signals */
+        sigaction(SIGINT, &saveintr, NULL);
+        sigaction(SIGQUIT, &savequit, NULL);
+        sigprocmask(SIG_SETMASK, &savemask, NULL);
+
         /* Redirect stdout and stderr to pipes inherited from the parent. */
         dup2( out[ EXECCMD_PIPE_WRITE ], STDOUT_FILENO );
         dup2( globs.pipe_action ? err[ EXECCMD_PIPE_WRITE ] :
@@ -236,7 +259,10 @@ void exec_cmd
             r_limit.rlim_max = globs.timeout;
             setrlimit( RLIMIT_CPU, &r_limit );
         }
-        setpgid( pid, pid );
+        if (0 != setpgid( pid, pid )) {
+            perror("setpgid(child)");
+            /* exit( EXITBAD ); */
+        }
         execvp( argv[ 0 ], (char * *)argv );
         perror( "execvp" );
         _exit( 127 );
@@ -245,7 +271,9 @@ void exec_cmd
     /******************/
     /* Parent process */
     /******************/
-    setpgid( cmdtab[ slot ].pid, cmdtab[ slot ].pid );
+
+    /* redundant call, ignore return value */
+    setpgid(cmdtab[ slot ].pid, cmdtab[ slot ].pid);
 
     /* Parent not need the write pipe ends used by the child. */
     close( out[ EXECCMD_PIPE_WRITE ] );
@@ -281,6 +309,11 @@ void exec_cmd
     /* Save input data into the selected running commands table slot. */
     cmdtab[ slot ].func = func;
     cmdtab[ slot ].closure = closure;
+
+    /* restore previous signals */
+    sigaction(SIGINT, &saveintr, NULL);
+    sigaction(SIGQUIT, &savequit, NULL);
+    sigprocmask(SIG_SETMASK, &savemask, NULL);
 }
 
 #undef EXECCMD_PIPE_READ
@@ -448,10 +481,17 @@ void exec_wait()
 
         /* select() will wait for I/O on a descriptor, a signal, or timeout. */
         {
+            /* disable child termination signals while in select */
             int ret;
+            sigset_t sigmask;
+            sigemptyset(&sigmask);
+            sigaddset(&sigmask, SIGCHLD);
+            sigprocmask(SIG_BLOCK, &sigmask, NULL);
             while ( ( ret = select( fd_max + 1, &fds, 0, 0, ptv ) ) == -1 )
                 if ( errno != EINTR )
                     break;
+            /* restore original signal mask by unblocking sigchld */
+            sigprocmask(SIG_UNBLOCK, &sigmask, NULL);
             if ( ret <= 0 )
                 continue;
         }