* use fnv hash function for all hash.

* add version field in SHM.
* clean up & reorder SHM, add gaps between arrays.
* enlarge USHM_SIZE.
* remove unused shmsweep.c.
* WARNING, you need to stop bbs and clean old shm before run this revision.


git-svn-id: http://opensvn.csie.org/pttbbs/trunk/pttbbs@2549 63ad8ddf-47c3-0310-b6dd-a9e9d9715204

6 files changed, 30 insertions, 37 deletions

diff --git a/mbbsd/cache.c b/mbbsd/cache.c
index 469acc46..4345e282 100644
--- a/mbbsd/cache.c
+++ b/mbbsd/cache.c
@@ -65,6 +65,12 @@ void
 attach_SHM(void)
 {
     SHM = attach_shm(SHM_KEY, sizeof(SHM_t));
+    if(SHM->version != SHM_VERSION) {
+      fprintf(stderr, "Error: SHM->version(%d) != SHM_VERSION(%d)\n", SHM->version, SHM_VERSION);
+      fprintf(stderr, "Please use the source code version corresponding to SHM,\n"
+	 "or use ipcrm(1) command to clean share memory.\n");
+      exit(1);
+    }
     if (!SHM->loaded)		/* (uhash) assume fresh shared memory is
 				 * zeroed */
 	exit(1);
@@ -73,7 +79,6 @@ attach_SHM(void)
     bcache = SHM->bcache;
     numboards = SHM->Bnumber;
 
-    GLOBALVAR = SHM->GLOBALVAR;
     if (SHM->Ptouchtime == 0)
 	SHM->Ptouchtime = 1;
 
@@ -142,9 +147,12 @@ sem_lock(int op, int semid)
 void
 add_to_uhash(int n, char *id)
 {
-    int            *p, h = StringHash(id);
+    int            *p, h = StringHash(id)%(1<<HASH_BITS);
     int             times;
     strlcpy(SHM->userid[n], id, sizeof(SHM->userid[n]));
+#if (1<<HASH_BITS)*2 < MAX_USERS
+#error "HASH_BITS too small"
+#endif
 
     p = &(SHM->hash_head[h]);
 
@@ -164,7 +172,7 @@ remove_from_uhash(int n)
  * note: after remove_from_uhash(), you should add_to_uhash() (likely with a
  * different name)
  */
-    int             h = StringHash(SHM->userid[n]);
+    int             h = StringHash(SHM->userid[n])%(1<<HASH_BITS);
     int            *p = &(SHM->hash_head[h]);
     int             times;
 
@@ -182,7 +190,7 @@ int
 searchuser(char *userid)
 {
     int             h, p, times;
-    h = StringHash(userid);
+    h = StringHash(userid)%(1<<HASH_BITS);
     p = SHM->hash_head[h];
 
     for (times = 0; times < MAX_USERS && p != -1 && p < MAX_USERS ; ++times) {
@@ -265,9 +273,10 @@ void
 getnewutmpent(userinfo_t * up)
 {
 /* Ptt:這裡加上 hash 觀念找空的 utmp */
-    register int    i, p;
+    register int    i;
     register userinfo_t *uentp;
-    for (i = 0, p = StringHash(up->userid) % USHM_SIZE; i < USHM_SIZE; i++, p++) {
+    unsigned int p = StringHash(up->userid) % USHM_SIZE;
+    for (i = 0; i < USHM_SIZE; i++, p++) {
 	if (p == USHM_SIZE)
 	    p = 0;
 	uentp = &(SHM->uinfo[p]);
@@ -1000,7 +1009,7 @@ hbflreload(int bid)
 	fclose(fp);
     }
     hbfl[0] = COMMON_TIME;
-    memcpy(SHM->hbfl[bid], hbfl, sizeof(hbfl)); // FIXME bid-1 ?
+    memcpy(SHM->hbfl[bid-1], hbfl, sizeof(hbfl));
 }
 
 /* 是否"不"通過板友測試. 如果在板友名單中的話傳回 0, 否則為 1 */
@@ -1009,11 +1018,10 @@ hbflcheck(int bid, int uid)
 {
     int             i;
 
-    // FIXME bid-1?
-    if (SHM->hbfl[bid][0] < login_start_time - HBFLexpire)
+    if (SHM->hbfl[bid-1][0] < login_start_time - HBFLexpire)
 	hbflreload(bid);
-    for (i = 1; SHM->hbfl[bid][i] != 0 && i <= MAX_FRIEND; ++i) {
-	if (SHM->hbfl[bid][i] == uid)
+    for (i = 1; SHM->hbfl[bid-1][i] != 0 && i <= MAX_FRIEND; ++i) {
+	if (SHM->hbfl[bid-1][i] == uid)
 	    return 0;
     }
     return 1;
diff --git a/mbbsd/cal.c b/mbbsd/cal.c
index 1c997836..d0fb17b3 100644
--- a/mbbsd/cal.c
+++ b/mbbsd/cal.c
@@ -3,18 +3,21 @@
 
 /* 防堵 Multi play */
 static int
-count_multiplay(int unmode)
+is_playing(int unmode)
 {
     register int    i, j;
     register userinfo_t *uentp;
+    unsigned int p = StringHash(cuser.userid) % USHM_SIZE;
 
     for (i = j = 0; i < USHM_SIZE; i++) { // XXX linear search
-	uentp = &(SHM->uinfo[i]);
+	if (p == USHM_SIZE)
+	    p = 0;
+	uentp = &(SHM->uinfo[p]);
 	if (uentp->uid == usernum)
 	    if (uentp->lockmode == unmode)
-		j++;
+		return 1;
     }
-    return j;
+    return 0;
 }
 
 int
@@ -24,7 +27,7 @@ lockutmpmode(int unmode, int state)
 
     if (currutmp->lockmode)
 	errorno = 1;
-    else if (count_multiplay(unmode))
+    else if (is_playing(unmode))
 	errorno = 2;
 
     if (errorno && !(state == LOCK_THIS && errorno == LOCK_MULTI)) {
diff --git a/mbbsd/read.c b/mbbsd/read.c
index 58a8678f..cf471688 100644
--- a/mbbsd/read.c
+++ b/mbbsd/read.c
@@ -208,6 +208,7 @@ getkeep(char *s, int def_topline, int def_cursline)
      * 一方面 size 小, malloc space overhead 就高, 因此改成 link block,
      * 以 KEEPSLOT 為一個 block 的 link list.
      * 只有第一個 block 可能沒滿. */
+    /* TODO LRU recycle? 麻煩在於別處可能把 keeploc_t pointer 記著... */
 #define KEEPSLOT 10
     struct keepsome {
 	unsigned char used;
diff --git a/mbbsd/stuff.c b/mbbsd/stuff.c
index 2ea16fec..3d3b90f8 100644
--- a/mbbsd/stuff.c
+++ b/mbbsd/stuff.c
@@ -1,5 +1,6 @@
 /* $Id$ */
 #include "bbs.h"
+#include "fnv_hash.h"
 
 /* ----------------------------------------------------- */
 /* set file path for boards/user home                    */
@@ -895,12 +896,7 @@ void FREE(void *ptr)
 unsigned
 StringHash(unsigned char *s)
 {
-    unsigned int    v = 0;
-    while (*s) {
-	v = (v << 8) | (v >> 24);
-	v ^= toupper(*s++);	/* note this is case insensitive */
-    }
-    return (v * 2654435769U) >> (32 - HASH_BITS);
+    return fnv1a_32_strcase(s, FNV1_32_INIT);
 }
 
 inline int *intbsearch(int key, int *base0, int nmemb)
diff --git a/mbbsd/var.c b/mbbsd/var.c
index ff880155..95cdad2e 100644
--- a/mbbsd/var.c
+++ b/mbbsd/var.c
@@ -356,7 +356,6 @@ int             wmofo = NOTREPLYING;
 
 /* cache.c */
 int             numboards = -1;
-int            *GLOBALVAR;
 SHM_t          *SHM;
 boardheader_t  *bcache;
 userinfo_t     *currutmp;
diff --git a/mbbsd/xyz.c b/mbbsd/xyz.c
index b757392d..003f5a51 100644
--- a/mbbsd/xyz.c
+++ b/mbbsd/xyz.c
@@ -335,19 +335,6 @@ m_sysop()
     return 0;
 }
 
-void 
-log_memoryusage(void)
-{
-#ifdef IA32
-  int use=((int)sbrk(0)-0x8048000)/1024;
-  if(use<500)
-    use=499;
-  if(use>1000)
-    use=1000;
-  GLOBALVAR[use/100-4]++; // use [0]~[6]
-#endif
-}
-
 int
 Goodbye()
 {
@@ -369,7 +356,6 @@ Goodbye()
 	else if (genbuf[0] == 'n')
 	    note();
     }
-    log_memoryusage();
     clear();
     prints("\033[1;36m親愛的 \033[33m%s(%s)\033[36m，別忘了再度光臨\033[45;33m"
 	   " %s \033[40;36m！\n以下是您在站內的註冊資料:\033[0m\n",