treewide: "require" + "use" cleanup and docs

[public-inbox.git] / lib / PublicInbox / Spawn.pm

diff --git a/lib/PublicInbox/Spawn.pm b/lib/PublicInbox/Spawn.pm
index d624c521ade4cc20f16c04b3e6f634e3e7753d65..1c74a5964aa59235d51eaa6af7bbb9b37fecb4eb 100644 (file)
--- a/lib/PublicInbox/Spawn.pm
+++ b/lib/PublicInbox/Spawn.pm
@@ -15,7 +15,6 @@ use strict;
 use warnings;
 use base qw(Exporter);
 use Symbol qw(gensym);
-use IO::Handle;
 use PublicInbox::ProcessPipe;
 our @EXPORT_OK = qw/which spawn popen_rd/;
 sub RLIMITS () { qw(RLIMIT_CPU RLIMIT_CORE RLIMIT_DATA) }
@@ -56,26 +55,10 @@ my $vfork_spawn = <<'VFORK_SPAWN';
        dst[real_len] = 0; \
 } while (0)
 
-static void *deconst(const char *s)
-{
-       union { const char *in; void *out; } u;
-       u.in = s;
-       return u.out;
-}
-
 /* needs to be safe inside a vfork'ed process */
-static void xerr(const char *msg)
+static void exit_err(int *cerrnum)
 {
-       struct iovec iov[3];
-       const char *err = strerror(errno); /* should be safe in practice */
-
-       iov[0].iov_base = deconst(msg);
-       iov[0].iov_len = strlen(msg);
-       iov[1].iov_base = deconst(err);
-       iov[1].iov_len = strlen(err);
-       iov[2].iov_base = deconst("\n");
-       iov[2].iov_len = 1;
-       writev(2, iov, 3);
+       *cerrnum = errno;
        _exit(1);
 }
 
@@ -95,7 +78,7 @@ int pi_fork_exec(SV *redirref, SV *file, SV *cmdref, SV *envref, SV *rlimref,
        pid_t pid;
        char **argv, **envp;
        sigset_t set, old;
-       int ret, errnum;
+       int ret, perrnum, cerrnum = 0;
 
        AV2C_COPY(argv, cmd);
        AV2C_COPY(envp, env);
@@ -115,12 +98,12 @@ int pi_fork_exec(SV *redirref, SV *file, SV *cmdref, SV *envref, SV *rlimref,
                        if (parent_fd == child_fd)
                                continue;
                        if (dup2(parent_fd, child_fd) < 0)
-                               xerr("dup2");
+                               exit_err(&cerrnum);
                }
                for (sig = 1; sig < NSIG; sig++)
                        signal(sig, SIG_DFL); /* ignore errors on signals */
                if (*cd && chdir(cd) < 0)
-                       xerr("chdir");
+                       exit_err(&cerrnum);
 
                max = av_len(rlim);
                for (i = 0; i < max; i += 3) {
@@ -132,7 +115,7 @@ int pi_fork_exec(SV *redirref, SV *file, SV *cmdref, SV *envref, SV *rlimref,
                        rl.rlim_cur = SvIV(*soft);
                        rl.rlim_max = SvIV(*hard);
                        if (setrlimit(SvIV(*res), &rl) < 0)
-                               xerr("sertlimit");
+                               exit_err(&cerrnum);
                }
 
                /*
@@ -140,13 +123,19 @@ int pi_fork_exec(SV *redirref, SV *file, SV *cmdref, SV *envref, SV *rlimref,
                 * to the group taking out a subprocess
                 */
                execve(filename, argv, envp);
-               xerr("execve failed");
+               exit_err(&cerrnum);
        }
-       errnum = errno;
+       perrnum = errno;
        ret = sigprocmask(SIG_SETMASK, &old, NULL);
        assert(ret == 0 && "BUG calling sigprocmask to restore");
-       errno = errnum;
-
+       if (cerrnum) {
+               if (pid > 0)
+                       waitpid(pid, NULL, 0);
+               pid = -1;
+               errno = cerrnum;
+       } else if (perrnum) {
+               errno = perrnum;
+       }
        return (int)pid;
 }
 VFORK_SPAWN