[hackers] [quark] Refine error messages || Laslo Hunhold

[git]

commit 33d3d85f4f54f7c6e7aadec4f8f1b0f7b89b01d8
Author:     Laslo Hunhold <d...@frign.de>
AuthorDate: Sun Feb 4 21:40:51 2018 +0100
Commit:     Laslo Hunhold <d...@frign.de>
CommitDate: Sun Feb 4 21:40:51 2018 +0100

    Refine error messages
    
    I forgot that they can fail with errno = 0, which indicates that the
    given entry was not found.

diff --git a/main.c b/main.c
index 5dc9034..28b78c9 100644
--- a/main.c
+++ b/main.c
@@ -198,11 +198,13 @@ main(int argc, char *argv[])
        /* validate user and group */
        errno = 0;
        if (user && !(pwd = getpwnam(user))) {
-               die("getpwnam '%s':", user);
+               die("getpwnam '%s': %s", user, errno ? strerror(errno) :
+                   "Entry not found");
        }
        errno = 0;
        if (group && !(grp = getgrnam(group))) {
-               die("getgrnam '%s':", group);
+               die("getgrnam '%s': %s", group, errno ? strerror(errno) :
+                   "Entry not found");
        }
 
        handlesignals(sigcleanup);
@@ -243,10 +245,10 @@ main(int argc, char *argv[])
                        die("setuid:");
                }
                if (getuid() == 0) {
-                       die("won't run as root user", argv0);
+                       die("Won't run as root user", argv0);
                }
                if (getgid() == 0) {
-                       die("won't run as root group", argv0);
+                       die("Won't run as root group", argv0);
                }
 
                serve(insock);