Code review for postmaster.pid contents changes.

Fix broken test for pre-existing postmaster, caused by wrong code for
appending lines to the lockfile; don't write a failed listen_address
setting into the lockfile; don't arbitrarily change the location of the
data directory in the lockfile compared to previous releases; provide more
consistent and useful definitions of the socket path and listen_address
entries; avoid assuming that pg_ctl has the same DEFAULT_PGSOCKET_DIR as
the postmaster; assorted code style improvements.

1 files changed, 26 insertions, 2 deletions

diff --git a/src/include/miscadmin.h b/src/include/miscadmin.h
index 382a5deced4..aa8cce5ca81 100644
--- a/src/include/miscadmin.h
+++ b/src/include/miscadmin.h
@@ -348,11 +348,35 @@ extern PGDLLIMPORT bool process_shared_preload_libraries_in_progress;
 extern char *shared_preload_libraries_string;
 extern char *local_preload_libraries_string;
 
-#define LOCK_FILE_LINES		7
+/*
+ * As of 9.1, the contents of the data-directory lock file are:
+ *
+ * line #
+ *		1	postmaster PID (or negative of a standalone backend's PID)
+ *		2	data directory path
+ *		3	postmaster start timestamp (time_t representation)
+ *		4	port number
+ *		5	socket directory path (empty on Windows)
+ *		6	first listen_address (IP address or "*"; empty if no TCP port)
+ *		7	shared memory key (not present on Windows)
+ *
+ * Lines 6 and up are added via AddToDataDirLockFile() after initial file
+ * creation; they have to be ordered according to time of addition.
+ *
+ * The socket lock file, if used, has the same contents as lines 1-5.
+ */
+#define LOCK_FILE_LINE_PID			1
+#define LOCK_FILE_LINE_DATA_DIR		2
+#define LOCK_FILE_LINE_START_TIME	3
+#define LOCK_FILE_LINE_PORT			4
+#define LOCK_FILE_LINE_SOCKET_DIR	5
+#define LOCK_FILE_LINE_LISTEN_ADDR	6
+#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 AddToLockFile(int target_line, const char *str);
+extern void AddToDataDirLockFile(int target_line, const char *str);
 extern void ValidatePgVersion(const char *path);
 extern void process_shared_preload_libraries(void);
 extern void process_local_preload_libraries(void);