Support having multiple Unix-domain sockets per postmaster.

Replace unix_socket_directory with unix_socket_directories, which is a list
of socket directories, and adjust postmaster's code to allow zero or more
Unix-domain sockets to be created.

This is mostly a straightforward change, but since the Unix sockets ought
to be created after the TCP/IP sockets for safety reasons (better chance
of detecting a port number conflict), AddToDataDirLockFile needs to be
fixed to support out-of-order updates of data directory lockfile lines.
That's a change that had been foreseen to be necessary someday anyway.

Honza Horak, reviewed and revised by Tom Lane

1 files changed, 4 insertions, 3 deletions

diff --git a/src/include/miscadmin.h b/src/include/miscadmin.h
index 8df2a28126a..9f57989f805 100644
--- a/src/include/miscadmin.h
+++ b/src/include/miscadmin.h
@@ -411,7 +411,7 @@ extern char *local_preload_libraries_string;
  *		2	data directory path
  *		3	postmaster start timestamp (time_t representation)
  *		4	port number
- *		5	socket directory path (empty on Windows)
+ *		5	first Unix socket directory path (empty if none)
  *		6	first listen_address (IP address or "*"; empty if no TCP port)
  *		7	shared memory key (not present on Windows)
  *
@@ -429,8 +429,9 @@ extern char *local_preload_libraries_string;
 #define LOCK_FILE_LINE_SHMEM_KEY	7
 
 extern void CreateDataDirLockFile(bool amPostmaster);
-extern void CreateSocketLockFile(const char *socketfile, bool amPostmaster);
-extern void TouchSocketLockFile(void);
+extern void CreateSocketLockFile(const char *socketfile, bool amPostmaster,
+					 const char *socketDir);
+extern void TouchSocketLockFiles(void);
 extern void AddToDataDirLockFile(int target_line, const char *str);
 extern void ValidatePgVersion(const char *path);
 extern void process_shared_preload_libraries(void);