Handling of double-quotes in command-line arguments of log_proxy_wrapper

[mk-fg]

Currently log_proxy_wrapper creates log_proxy subprocess like this:

gchar *cli = g_strdup_printf("log_proxy -s %li -t %li -S \"%s\" -n %i %s -r -f \"%s\" \"%s\"", rotation_size, rotation_time, rotation_suffix, rotated_files, use_locks_str, fifo_path, log_path);
gboolean spawn_res = g_spawn_command_line_async(cli, NULL);

Which I think should not work if any of the string values templated there have double-quote characters in them.

For example:

log_proxy_wrapper -S '.%Y%m%d_%H%M%S"' -O /tmp/test.log -- cat <<< test

I'd expect this to work for any valid strftime template, which can include double quotes, but it does not with current release version, with the following error:

(log_proxy_wrapper:121851): log_proxy-CRITICAL **: 03:08:45.541: can't spawn log_proxy -s 104857600 -t 86400 -S ".%Y%m%d_%H%M%S"" -T "(null)" -n 5  -r -f "/tmp/log_proxy_stdout_4c2e654e021d1c1d8acbfadbb111e995.fifo" "/tmp/test.log" => exit

Fix can probably be using a different g_spawn_* call, which passes through individual arguments to underlying exec syscall, instead of parsing them from a shell-like quoted string, which will always be unreliable and depending on that parsing logic.