From d703a66988f71d4d0b7709c6e2671678706cf387 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Adrien=20Gallou=C3=ABt?= <adrien@gallouet.fr>
Date: Tue, 2 Apr 2019 13:51:15 +0000
Subject: [PATCH] Compute sun_path from PID
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Signed-off-by: Adrien Gallouët <adrien@gallouet.fr>
---
 src/ctl.c | 22 ++++++++++------------
 1 file changed, 10 insertions(+), 12 deletions(-)

diff --git a/src/ctl.c b/src/ctl.c
index 30df164..f28529f 100644
--- a/src/ctl.c
+++ b/src/ctl.c
@@ -2,15 +2,13 @@
 #include "ctl.h"
 #include "str.h"
 
-#include <stdio.h>
 #include <unistd.h>
 #include <dirent.h>
 #include <sys/socket.h>
+#include <sys/types.h>
 #include <sys/stat.h>
 #include <sys/un.h>
 
-#define CTL_BIND_MAX 64
-
 int
 ctl_reply(int fd, struct ctl_msg *res, struct ctl_msg *req)
 {
@@ -61,20 +59,20 @@ ctl_setsun(struct sockaddr_un *dst, const char *dir, const char *file)
 static int
 ctl_bind(int fd, const char *dir, const char *file)
 {
-    char tmp[32];
     struct sockaddr_un sun;
 
     if (str_empty(file)) {
-        for (int i = 0; i < CTL_BIND_MAX; i++) {
-            if (snprintf(tmp, sizeof(tmp), ".%i", i) >= sizeof(tmp))
-                return -1;
+        char name[10] = { [0] = '.' };
+        unsigned pid = (unsigned)getpid();
 
-            if (ctl_setsun(&sun, dir, tmp))
-                return -1;
+        for (size_t i = 1; i < sizeof(name) - 1; i++, pid >>= 4)
+            name[i] = "uncopyrightables"[pid & 15];
 
-            if (!bind(fd, (struct sockaddr *)&sun, sizeof(sun)))
-                return 0;
-        }
+        if (ctl_setsun(&sun, dir, name))
+            return -1;
+
+        if (!bind(fd, (struct sockaddr *)&sun, sizeof(sun)))
+            return 0;
     } else {
         if (ctl_setsun(&sun, dir, file))
             return -1;