Add real random() call to postmaster for use in cancel.

diff --git a/src/backend/postmaster/postmaster.c b/src/backend/postmaster/postmaster.c
index 8b95ac46e276e1735797ad8b3538b9cd8cbc4489..070fee16727b9f8aa32c67d55729cc1df8f7b0b2 100644 (file)
--- a/src/backend/postmaster/postmaster.c
+++ b/src/backend/postmaster/postmaster.c
@@ -10,7 +10,7 @@
  *
  *
  * IDENTIFICATION
- *       $Header: /cvsroot/pgsql/src/backend/postmaster/postmaster.c,v 1.80 1998/06/04 17:26:41 momjian Exp $
+ *       $Header: /cvsroot/pgsql/src/backend/postmaster/postmaster.c,v 1.81 1998/06/08 04:27:59 momjian Exp $
  *
  * NOTES
  *
@@ -198,6 +198,12 @@ static     sigset_t        oldsigmask,
 static int                     orgsigmask = sigblock(0);
 #endif
 
+static unsigned int random_seed = 0;
+
+extern char *optarg;
+extern int     optind,
+                       opterr;
+
                                                                 
 /*
  * postmaster.c - function prototypes
@@ -216,18 +222,14 @@ static int ServerLoop(void);
 static int BackendStartup(Port *port);
 static void readStartupPacket(char *arg, PacketLen len, char *pkt);
 static int initMasks(fd_set *rmask, fd_set *wmask);
+static long PostmasterRandom(void);
 static void RandomSalt(char *salt);
 
 #ifdef CYR_RECODE
-void           GetCharSetByHost(char *, int, char *);
+void GetCharSetByHost(char *, int, char *);
 
 #endif
 
-extern char *optarg;
-extern int     optind,
-                       opterr;
-
-
 
 static void
 checkDataDir(const char *DataDir, bool *DataDirOK)
@@ -563,6 +565,10 @@ ServerLoop(void)
                                writemask;
        int                     nSockets;
        Dlelem     *curr;
+       struct timeval now, later;
+       struct timezone tz;
+
+       gettimeofday(&now, &tz);
 
        nSockets = initMasks(&readmask, &writemask);
 
@@ -596,6 +602,19 @@ ServerLoop(void)
                        return (STATUS_ERROR);
                }
 
+               if (random_seed == 0)
+               {
+                       gettimeofday(&later, &tz);
+       
+                       /*
+                        *      We are not sure how much precision is in tv_usec, so we
+                        *      swap the nibbles of 'later' and XOR them with 'now'
+                        */
+                       random_seed = now.tv_usec ^
+                                       ((later.tv_usec << 16) |
+                                       ((unsigned int)(later.tv_usec & 0xffff0000) >> 16));
+               }
+                               
                /*
                 * [TRH] To avoid race conditions, block SIGCHLD signals while we
                 * are handling the request. (both reaper() and ConnCreate()
@@ -1345,19 +1364,28 @@ CharRemap(long int ch)
  */
 static void
 RandomSalt(char *salt)
+{
+       long rand = PostmasterRandom();
+       
+       *salt = CharRemap(rand % 62);
+       *(salt + 1) = CharRemap(rand / 62);
+}
+
+/*
+ * PostmasterRandom
+ */
+static long
+PostmasterRandom(void)
 {
 
        static bool initialized = false;
 
        if (!initialized)
        {
-               time_t          now;
-
-               now = time(NULL);
-               srandom((unsigned int) now);
+               Assert(random_seed != 0 && !IsUnderPostmaster);
+               srandom(random_seed);
                initialized = true;
        }
 
-       *salt = CharRemap(random());
-       *(salt + 1) = CharRemap(random());
+       return ramdom() ^ random_seed;
 }