Add ipc_bind_reuse_lock, rewrite ipc_bind_reuse to use it

4 files changed, 33 insertions, 8 deletions

diff --git a/package/deps.mak b/package/deps.mak
index 53afe3b..1f503d8 100644
--- a/package/deps.mak
+++ b/package/deps.mak
@@ -400,7 +400,8 @@ src/libstddjb/ip6_scan.o src/libstddjb/ip6_scan.lo: src/libstddjb/ip6_scan.c src
 src/libstddjb/ip6_scanlist.o src/libstddjb/ip6_scanlist.lo: src/libstddjb/ip6_scanlist.c src/include/skalibs/fmtscan.h
 src/libstddjb/ipc_accept.o src/libstddjb/ipc_accept.lo: src/libstddjb/ipc_accept.c src/include/skalibs/bytestr.h src/include/skalibs/djbunix.h src/include/skalibs/nonposix.h src/include/skalibs/sysdeps.h src/include/skalibs/webipc.h
 src/libstddjb/ipc_bind.o src/libstddjb/ipc_bind.lo: src/libstddjb/ipc_bind.c src/include/skalibs/nonposix.h src/include/skalibs/posixishard.h src/include/skalibs/webipc.h
-src/libstddjb/ipc_bind_reuse.o src/libstddjb/ipc_bind_reuse.lo: src/libstddjb/ipc_bind_reuse.c src/include/skalibs/nonposix.h src/include/skalibs/webipc.h
+src/libstddjb/ipc_bind_reuse.o src/libstddjb/ipc_bind_reuse.lo: src/libstddjb/ipc_bind_reuse.c src/include/skalibs/webipc.h
+src/libstddjb/ipc_bind_reuse_lock.o src/libstddjb/ipc_bind_reuse_lock.lo: src/libstddjb/ipc_bind_reuse_lock.c src/include/skalibs/nonposix.h src/include/skalibs/webipc.h
 src/libstddjb/ipc_connect.o src/libstddjb/ipc_connect.lo: src/libstddjb/ipc_connect.c src/include/skalibs/nonposix.h src/include/skalibs/posixishard.h src/include/skalibs/webipc.h
 src/libstddjb/ipc_connected.o src/libstddjb/ipc_connected.lo: src/libstddjb/ipc_connected.c src/include/skalibs/allreadwrite.h src/include/skalibs/nonposix.h src/include/skalibs/webipc.h
 src/libstddjb/ipc_dgram.o src/libstddjb/ipc_dgram.lo: src/libstddjb/ipc_dgram.c src/include/skalibs/djbunix.h src/include/skalibs/nonposix.h src/include/skalibs/webipc.h
diff --git a/src/include/skalibs/webipc.h b/src/include/skalibs/webipc.h
index eba6f6b..2a7e95e 100644
--- a/src/include/skalibs/webipc.h
+++ b/src/include/skalibs/webipc.h
@@ -40,6 +40,7 @@ extern int ipc_pair_internal (int *, unsigned int) ;
 
 extern int ipc_bind (int, char const *) ;
 extern int ipc_bind_reuse (int, char const *) ;
+extern int ipc_bind_reuse_lock (int, char const *, int *) ;
 extern int ipc_listen (int, int) ;
 
 #define ipc_accept(s, path, len, trunc) ipc_accept_internal(s, path, len, (trunc), 0)
diff --git a/src/libstddjb/ipc_bind_reuse.c b/src/libstddjb/ipc_bind_reuse.c
index 31db745..ce5c7a4 100644
--- a/src/libstddjb/ipc_bind_reuse.c
+++ b/src/libstddjb/ipc_bind_reuse.c
@@ -1,14 +1,9 @@
 /* ISC license. */
 
-#include <skalibs/nonposix.h>
-#include <sys/socket.h>
-#include <unistd.h>
 #include <skalibs/webipc.h>
 
 int ipc_bind_reuse (int s, char const *p)
 {
-  unsigned int opt = 1 ;
-  setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof opt) ;
-  unlink(p) ;
-  return ipc_bind(s, p) ;
+  int fdlock ;
+  return ipc_bind_reuse_lock(s, p, &fdlock) ;
 }
diff --git a/src/libstddjb/ipc_bind_reuse_lock.c b/src/libstddjb/ipc_bind_reuse_lock.c
new file mode 100644
index 0000000..aede744
--- /dev/null
+++ b/src/libstddjb/ipc_bind_reuse_lock.c
@@ -0,0 +1,28 @@
+/* ISC license. */
+
+#include <skalibs/nonposix.h>
+
+#include <string.h>
+#include <unistd.h>
+#include <sys/socket.h>
+
+#include <skalibs/djbunix.h>
+#include <skalibs/webipc.h>
+
+int ipc_bind_reuse_lock (int s, char const *p, int *fdlock)
+{
+  unsigned int opt = 1 ;
+  size_t len = strlen(p) ;
+  int fd ;
+  char lockname[len + 6] ;
+  memcpy(lockname, p, len) ;
+  memcpy(lockname + len, ".lock", 6) ;
+  fd = openc_create(lockname) ;
+  if (fd < 0) return -1 ;
+  if (lock_exnb(fd) < 0) return -1 ;
+  setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof opt) ;
+  unlink(p) ;
+  if (ipc_bind(s, p) < 0) return -1 ;
+  *fdlock = fd ;
+  return 0 ;
+}