e2lib: fix e2lib.wait() for signaled process

wait() returned 0 for a signaled process, expecting the caller to
check the third argument for a signal code.

Most call sites do not observe the signal argument, leading to
"successful" execution of a crashing process.

wait() will now return the exit code or signal + 128 in the first
argument. This is in line with various shells.

Also improve debug logging around wait() and callcmd().

Signed-off-by: Tobias Ulmer <tu@emlix.com>

diff --git a/Changelog b/Changelog
index 6225253a57d8dea6a1b0eb199c3d18528fd52228..a4f16368042b375a4bb2dd54bce70c313d8be9f1 100644 (file)
--- a/Changelog
+++ b/Changelog
@@ -1,4 +1,5 @@
 NEXT:
+ * fix detection of exit status of a signaled process
 
 e2factory-2.3.17
  * fixed sub-licences handling for file sources

diff --git a/generic/e2lib.lua b/generic/e2lib.lua
index b895e19d706b7e789e9e2cbaa0c08d4605244f2b..2072302a2cbb5530621429cce89c62ec2b747ffd 100644 (file)
--- a/generic/e2lib.lua
+++ b/generic/e2lib.lua
@@ -224,7 +224,7 @@ end
 
 --- Wait for process to terminate.
 -- @param pid Process ID, -1 to wait for any child.
--- @return Exit status of process (WEXITSTATUS), or false on error.
+-- @return Exit status of process, signal + 128, or false on error.
 -- @return Process ID of the terminated child or error object on failure.
 -- @return Number of signal that killed the process, if any.
 function e2lib.wait(pid)
@@ -1421,7 +1421,7 @@ function e2lib.callcmd(argv, fdctv, workdir, envdict, nowait)
 
     -- start of callcmd() proper
 
-    local rc, re, pid
+    local rc, re, pid, sig
     local sync_pipes = {}
 
     e2lib.logf(4, "calling %q in %q", table.concat(argv, " "),
@@ -1496,14 +1496,14 @@ function e2lib.callcmd(argv, fdctv, workdir, envdict, nowait)
         return pid
     end
 
-    e2lib.logf(4, "waiting for %q", table.concat(argv, " "))
-    rc, re = e2lib.wait(pid)
+    e2lib.logf(4, "waiting for command %s pid %d", table.concat(argv, " "), pid)
+    rc, re, sig = e2lib.wait(pid)
     if not rc then
         return false, re
     end
 
-    e2lib.logf(4, "command %q exit with return code %d",
-        table.concat(argv, " "), rc)
+    e2lib.logf(4, "command %q pid %d exit %d signal %d",
+        table.concat(argv, " "), re, rc, sig or 0)
 
     return rc
 end

diff --git a/generic/le2lib.c b/generic/le2lib.c
index 17431fd575212ccf490f1ea7e22253f1eb4c3fc5..2f31a761b88d0014f6941457dea62263d858c617 100644 (file)
--- a/generic/le2lib.c
+++ b/generic/le2lib.c
@@ -287,20 +287,26 @@ process_wait(lua_State *lua)
                return 2;
        }
 
-       if (!(WIFEXITED(status) || WIFSIGNALED(status))) {
-               lua_pushboolean(lua, 0);
-               lua_pushstring(lua, "process terminated(?) due to unknown cause");
-               return 2;
-       }
+       if (WIFEXITED(status)) {
+               /* Normal exit case */
+               lua_pushnumber(lua, WEXITSTATUS(status));
+               lua_pushnumber(lua, rc);
 
-       lua_pushnumber(lua, WEXITSTATUS(status));
-       lua_pushnumber(lua, rc);
-       if (WIFSIGNALED(status)) {
+               return 2;
+       } else if (WIFSIGNALED(status)) {
+               /* Signal exit case */
+               lua_pushnumber(lua, WTERMSIG(status) + 128); // what dash does
+               lua_pushnumber(lua, rc);
                lua_pushnumber(lua, WTERMSIG(status));
+
                return 3;
-       }
+       } else {
+               /* Job control status but option is unset */
+               lua_pushboolean(lua, 0);
+               lua_pushstring(lua, "internal error, please report (waitpid)");
 
-       return 2;
+               return 2;
+       }
 }
 
 static int