From 5a3865e59413cd51b7d55cbbfcf383c933ecb885 Mon Sep 17 00:00:00 2001
From: Martin Mares <mj@ucw.cz>
Date: Fri, 22 Aug 2008 19:02:18 +0200
Subject: [PATCH] Distinguish between die() and err().

die() is used for internal errors only and it exits with status 2,
err() is used for reporting errors of the process inside the box with status 1.
---
 box/box.c | 42 ++++++++++++++++++++++++++----------------
 1 file changed, 26 insertions(+), 16 deletions(-)

diff --git a/box/box.c b/box/box.c
index 40f96a9..09fb033 100644
--- a/box/box.c
+++ b/box/box.c
@@ -145,6 +145,17 @@ flush_line(void)
 
 static void NONRET __attribute__((format(printf,1,2)))
 die(char *msg, ...)
+{
+  va_list args;
+  va_start(args, msg);
+  flush_line();
+  vfprintf(stderr, msg, args);
+  fputc('\n', stderr);
+  box_exit(2);
+}
+
+static void NONRET __attribute__((format(printf,1,2)))
+err(char *msg, ...)
 {
   va_list args;
   va_start(args, msg);
@@ -152,7 +163,6 @@ die(char *msg, ...)
   vfprintf(stderr, msg, args);
   fputc('\n', stderr);
   box_exit(1);
-  // FIXME: exit(2) for errors of the box itself
 }
 
 static void __attribute__((format(printf,1,2)))
@@ -567,7 +577,7 @@ valid_filename(unsigned long addr)
   static int mem_fd;
 
   if (!file_access)
-    die("File access forbidden");
+    err("File access forbidden");
   if (file_access >= 9)
     return;
 
@@ -588,14 +598,14 @@ valid_filename(unsigned long addr)
 	  if (l > remains)
 	    l = remains;
 	  if (!l)
-	    die("Access to file with name too long");
+	    err("Access to file with name too long");
 	  if (long_seek(mem_fd, addr, SEEK_SET) < 0)
 	    die("long_seek(mem): %m");
 	  remains = read(mem_fd, end, l);
 	  if (remains < 0)
 	    die("read(mem): %m");
 	  if (!remains)
-	    die("Access to file with name out of memory");
+	    err("Access to file with name out of memory");
 	  end += l;
 	  addr += l;
 	}
@@ -625,7 +635,7 @@ valid_filename(unsigned long addr)
       act = match_path_rule(&default_path_rules[i], namebuf);
 
   if (act != A_YES)
-    die("Forbidden access to file `%s'", namebuf);
+    err("Forbidden access to file `%s'", namebuf);
 }
 
 static int
@@ -657,11 +667,11 @@ valid_syscall(struct user *u)
     {
     case __NR_kill:
       if (u->regs.ebx == box_pid)
-	die("Committed suicide by signal %d", (int)u->regs.ecx);
+	err("Committed suicide by signal %d", (int)u->regs.ecx);
       return 0;
     case __NR_tgkill:
       if (u->regs.ebx == box_pid && u->regs.ecx == box_pid)
-	die("Committed suicide by signal %d", (int)u->regs.edx);
+	err("Committed suicide by signal %d", (int)u->regs.edx);
       return 0;
     default:
       return 0;
@@ -680,7 +690,7 @@ static void
 signal_int(int unused UNUSED)
 {
   /* Interrupts are fatal, so no synchronization requirements. */
-  die("Interrupted");
+  err("Interrupted");
 }
 
 static void
@@ -694,7 +704,7 @@ check_timeout(void)
       timersub(&now, &start_time, &wall);
       wall_ms = wall.tv_sec*1000 + wall.tv_usec/1000;
       if (wall_ms > wall_timeout)
-        die("Time limit exceeded (wall clock)");
+        err("Time limit exceeded (wall clock)");
       if (verbose > 1)
         fprintf(stderr, "[wall time check: %d msec]\n", wall_ms);
     }
@@ -733,7 +743,7 @@ check_timeout(void)
       if (verbose > 1)
 	fprintf(stderr, "[time check: %d msec]\n", ms);
       if (ms > timeout)
-	die("Time limit exceeded");
+	err("Time limit exceeded");
     }
 }
 
@@ -782,11 +792,11 @@ boxkeeper(void)
 	  final_stats(&rus);
 	  // FIXME: If the process has exited before being ptraced, signal an internal error
 	  if (WEXITSTATUS(stat))
-	    die("Exited with error status %d", WEXITSTATUS(stat));
+	    err("Exited with error status %d", WEXITSTATUS(stat));
 	  if (timeout && total_ms > timeout)
-	    die("Time limit exceeded");
+	    err("Time limit exceeded");
 	  if (wall_timeout && wall_ms > wall_timeout)
-	    die("Time limit exceeded (wall clock)");
+	    err("Time limit exceeded (wall clock)");
 	  flush_line();
 	  fprintf(stderr, "OK (%d.%03d sec real, %d.%03d sec wall, %d syscalls)\n",
 	      total_ms/1000, total_ms%1000,
@@ -797,7 +807,7 @@ boxkeeper(void)
       if (WIFSIGNALED(stat))
 	{
 	  box_pid = 0;
-	  die("Caught fatal signal %d%s", WTERMSIG(stat), (syscall_count ? "" : " during startup"));
+	  err("Caught fatal signal %d%s", WTERMSIG(stat), (syscall_count ? "" : " during startup"));
 	}
       if (WIFSTOPPED(stat))
 	{
@@ -834,7 +844,7 @@ boxkeeper(void)
 		      u.regs.orig_eax = 0xffffffff;
 		      if (ptrace(PTRACE_SETREGS, box_pid, NULL, &u) < 0)
 			die("ptrace(PTRACE_SETREGS): %m");
-		      die("Forbidden syscall %s", syscall_name(sys, namebuf));
+		      err("Forbidden syscall %s", syscall_name(sys, namebuf));
 		    }
 		}
 	      else					/* Syscall return */
@@ -847,7 +857,7 @@ boxkeeper(void)
 	      ptrace(PTRACE_SYSCALL, box_pid, 0, sig);
 	    }
 	  else
-	    die("Received signal %d", sig);
+	    err("Received signal %d", sig);
 	}
       else
 	die("wait4: unknown status %x, giving up!", stat);
-- 
2.39.2