114/118: nix-daemon: Call exit(), not _exit()

[Ludovic Courtès]

civodul pushed a commit to branch nix
in repository guix.

commit 4eb62b5230c29e2f6ab17352439521083846c259
Author: Eelco Dolstra <address@hidden>
Date:   Wed Nov 19 17:09:27 2014 +0100

    nix-daemon: Call exit(), not _exit()
    
    This was preventing destructors from running. In particular, it was
    preventing the deletion of the temproot file for each worker
    process. It may also have been responsible for the excessive WAL
    growth on Hydra (due to the SQLite database not being closed
    properly).
    
    Apparently broken by accident in
    8e9140cfdef9dbd1eb61e4c75c91d452ab5e4a74.
---
 nix/libutil/util.cc          |    8 ++++++--
 nix/libutil/util.hh          |    3 ++-
 nix/nix-daemon/nix-daemon.cc |    4 ++--
 3 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/nix/libutil/util.cc b/nix/libutil/util.cc
index ad3b3c3..a4a1ddb 100644
--- a/nix/libutil/util.cc
+++ b/nix/libutil/util.cc
@@ -858,7 +858,8 @@ void killUser(uid_t uid)
 //////////////////////////////////////////////////////////////////////
 
 
-pid_t startProcess(std::function<void()> fun, const string & errorPrefix)
+pid_t startProcess(std::function<void()> fun,
+    bool dieWithParent, const string & errorPrefix, bool runExitHandlers)
 {
     pid_t pid = fork();
     if (pid == -1) throw SysError("unable to fork");
@@ -873,7 +874,10 @@ pid_t startProcess(std::function<void()> fun, const string 
& errorPrefix)
                 std::cerr << errorPrefix << e.what() << "\n";
             } catch (...) { }
         } catch (...) { }
-        _exit(1);
+        if (runExitHandlers)
+            exit(1);
+        else
+            _exit(1);
     }
 
     return pid;
diff --git a/nix/libutil/util.hh b/nix/libutil/util.hh
index 418d76d..0ad0026 100644
--- a/nix/libutil/util.hh
+++ b/nix/libutil/util.hh
@@ -269,7 +269,8 @@ void killUser(uid_t uid);
 
 /* Fork a process that runs the given function, and return the child
    pid to the caller. */
-pid_t startProcess(std::function<void()> fun, const string & errorPrefix = 
"error: ");
+pid_t startProcess(std::function<void()> fun, bool dieWithParent = true,
+    const string & errorPrefix = "error: ", bool runExitHandlers = false);
 
 
 /* Run a program and return its stdout in a string (i.e., like the
diff --git a/nix/nix-daemon/nix-daemon.cc b/nix/nix-daemon/nix-daemon.cc
index 2fa3632..e42d602 100644
--- a/nix/nix-daemon/nix-daemon.cc
+++ b/nix/nix-daemon/nix-daemon.cc
@@ -924,8 +924,8 @@ static void daemonLoop()
                 to.fd = remote;
                 processConnection(trusted);
 
-                _exit(0);
-            }, "unexpected Nix daemon error: ");
+                exit(0);
+            }, false, "unexpected Nix daemon error: ", true);
 
         } catch (Interrupted & e) {
             throw;