Converted to Mersenne Twister for random.

Randomerer! Also: Fixed a security problem. Can you find it?

17 files changed, 234 insertions, 113 deletions

diff --git a/src/char/Makefile b/src/char/Makefile
index d4344a0..841edfd 100644
--- a/src/char/Makefile
+++ b/src/char/Makefile
@@ -1,8 +1,8 @@
 all: char-server
 txt: char-server
 
-COMMON_OBJ = ../common/core.o ../common/socket.o ../common/timer.o ../common/db.o ../common/lock.o ../common/malloc.o
-COMMON_H = ../common/core.h ../common/socket.h ../common/timer.h ../common/mmo.h ../common/db.h ../common/lock.h ../common/timer.h ../common/malloc.h
+COMMON_OBJ = ../common/core.o ../common/socket.o ../common/timer.o ../common/db.o ../common/lock.o ../common/malloc.o ../common/mt_rand.o
+COMMON_H = ../common/core.h ../common/socket.h ../common/timer.h ../common/mmo.h ../common/db.h ../common/lock.h ../common/timer.h ../common/malloc.h ../common/mt_rand.h
 char-server: char.o inter.o int_party.o int_guild.o int_storage.o $(COMMON_OBJ)
 	$(CC) -o ../../$@ $>
 
diff --git a/src/common/Makefile b/src/common/Makefile
index b5b8f7c..9218a55 100644
--- a/src/common/Makefile
+++ b/src/common/Makefile
@@ -1,4 +1,4 @@
-txt sql all: core.o socket.o timer.o grfio.o db.o lock.o nullpo.o malloc.o
+txt sql all: core.o socket.o timer.o grfio.o db.o lock.o nullpo.o malloc.o mt_rand.o
 
 core.o: core.c core.h
 socket.o: socket.c socket.h mmo.h
@@ -8,6 +8,7 @@ db.o: db.c db.h
 lock.o: lock.h
 nullpo.o: nullpo.c nullpo.h
 malloc.o: malloc.c malloc.h
+mt_rand.o: mt_rand.c mt_rand.h
 
 clean:
 	rm -f *.o
diff --git a/src/common/core.c b/src/common/core.c
index 7267d8f..94a754b 100644
--- a/src/common/core.c
+++ b/src/common/core.c
@@ -13,6 +13,7 @@
 #include "socket.h"
 #include "timer.h"
 #include "version.h"
+#include "mt_rand.h"
 
 #ifdef MEMWATCH
 #include "memwatch.h"
@@ -133,6 +134,8 @@ int main(int argc,char **argv)
 {
 	int next;
 
+	mt_seed(time(NULL) ^ getpid() ^ getppid());
+
 	Net_Init();
 	do_socket();
 
diff --git a/src/common/mt_rand.c b/src/common/mt_rand.c
new file mode 100644
index 0000000..ab733ae
--- /dev/null
+++ b/src/common/mt_rand.c
@@ -0,0 +1,110 @@
+/*
+// This is the ``Mersenne Twister'' random number generator MT19937, which
+// generates pseudorandom integers uniformly distributed in 0..(2^32 - 1)
+// starting from any odd seed in 0..(2^32 - 1).  This version is a recode
+// by Shawn Cokus (Cokus@math.washington.edu) on March 8, 1998 of a version by
+// Takuji Nishimura (who had suggestions from Topher Cooper and Marc Rieffel in
+// July-August 1997).
+//
+// Effectiveness of the recoding (on Goedel2.math.washington.edu, a DEC Alpha
+// running OSF/1) using GCC -O3 as a compiler: before recoding: 51.6 sec. to
+// generate 300 million random numbers; after recoding: 24.0 sec. for the same
+// (i.e., 46.5% of original time), so speed is now about 12.5 million random
+// number generations per second on this machine.
+//
+// According to the URL <http://www.math.keio.ac.jp/~matumoto/emt.html>
+// (and paraphrasing a bit in places), the Mersenne Twister is ``designed
+// with consideration of the flaws of various existing generators,'' has
+// a period of 2^19937 - 1, gives a sequence that is 623-dimensionally
+// equidistributed, and ``has passed many stringent tests, including the
+// die-hard test of G. Marsaglia and the load test of P. Hellekalek and
+// S. Wegenkittl.''  It is efficient in memory usage (typically using 2506
+// to 5012 bytes of static data, depending on data type sizes, and the code
+// is quite short as well).  It generates random numbers in batches of 624
+// at a time, so the caching and pipelining of modern systems is exploited.
+// It is also divide- and mod-free.
+//
+// This library is free software; you can redistribute it and/or modify it
+// under the terms of the GNU Library General Public License as published by
+// the Free Software Foundation (either version 2 of the License or, at your
+// option, any later version).  This library is distributed in the hope that
+// it will be useful, but WITHOUT ANY WARRANTY, without even the implied
+// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
+// the GNU Library General Public License for more details.  You should have
+// received a copy of the GNU Library General Public License along with this
+// library; if not, write to the Free Software Foundation, Inc., 59 Temple
+// Place, Suite 330, Boston, MA 02111-1307, USA.
+//
+// The code as Shawn received it included the following notice:
+//
+//   Copyright (C) 1997 Makoto Matsumoto and Takuji Nishimura.  When
+//   you use this, send an e-mail to <matumoto@math.keio.ac.jp> with
+//   an appropriate reference to your work.
+//
+// It would be nice to CC: <Cokus@math.washington.edu> when you write.
+//
+*/
+
+#include <time.h>
+#include "mt_rand.h"
+
+#define N              (624)                 /* length of state vector */
+#define M              (397)                 /* a period parameter */
+#define K              (0x9908B0DFU)         /* a magic constant */
+#define hiBit(u)       ((u) & 0x80000000U)   /* mask all but highest bit of u */
+#define loBit(u)       ((u) & 0x00000001U)   /* mask all but lowest bit of u */
+#define loBits(u)      ((u) & 0x7FFFFFFFU)   /* mask the highest bit of u */
+#define mixBits(u, v)  (hiBit(u)|loBits(v))  /* move hi bit of u to hi bit of v */
+
+static unsigned long   state[N+1];     /* state vector + 1 extra to not violate ANSI C */
+static unsigned long   *next;          /* next random value is computed from here */
+static int     left = -1;      /* can *next++ this many times before reloading */
+
+
+void mt_seed(unsigned long seed)
+{
+    register unsigned long x = (seed | 1U) & 0xFFFFFFFFU, *s = state;
+    register int    j;
+
+    for(left=0, *s++=x, j=N; --j;
+        *s++ = (x*=69069U) & 0xFFFFFFFFU);
+}
+
+
+unsigned long mt_reload(void)
+{
+    register unsigned long *p0=state, *p2=state+2, *pM=state+M, s0, s1;
+    register int    j;
+
+    if(left < -1)
+        mt_seed(time(NULL));
+
+    left=N-1, next=state+1;
+
+    for(s0=state[0], s1=state[1], j=N-M+1; --j; s0=s1, s1=*p2++)
+        *p0++ = *pM++ ^ (mixBits(s0, s1) >> 1) ^ (loBit(s1) ? K : 0U);
+
+    for(pM=state, j=M; --j; s0=s1, s1=*p2++)
+        *p0++ = *pM++ ^ (mixBits(s0, s1) >> 1) ^ (loBit(s1) ? K : 0U);
+
+    s1=state[0], *p0 = *pM ^ (mixBits(s0, s1) >> 1) ^ (loBit(s1) ? K : 0U);
+    s1 ^= (s1 >> 11);
+    s1 ^= (s1 <<  7) & 0x9D2C5680U;
+    s1 ^= (s1 << 15) & 0xEFC60000U;
+    return(s1 ^ (s1 >> 18));
+}
+
+
+unsigned long mt_random(void)
+{
+    unsigned long y;
+
+    if(--left < 0)
+        return(mt_reload());
+
+    y  = *next++;
+    y ^= (y >> 11);
+    y ^= (y <<  7) & 0x9D2C5680U;
+    y ^= (y << 15) & 0xEFC60000U;
+    return(y ^ (y >> 18));
+}
diff --git a/src/common/mt_rand.h b/src/common/mt_rand.h
new file mode 100644
index 0000000..07f6ef0
--- /dev/null
+++ b/src/common/mt_rand.h
@@ -0,0 +1,8 @@
+#ifndef __mt_rand_h
+#define __mt_rand_h
+
+void mt_seed(unsigned long seed);
+unsigned long mt_reload(void);
+unsigned long mt_random(void);
+
+#endif /* __mt_rand_h */
diff --git a/src/common/utils.h b/src/common/utils.h
index 794a0b6..ba96da1 100644
--- a/src/common/utils.h
+++ b/src/common/utils.h
@@ -1,3 +1,4 @@
+#include "mt_rand.h"
 
 #ifndef NULL
 #define NULL (void *)0
@@ -38,5 +39,5 @@
  * MRAND(10), returns 0-9.
  * MPRAND(5,10) returns 5-14.
  */
-#define MRAND(mod) (int) ((float)mod * (rand() / (RAND_MAX + 1.0)))
+#define MRAND(mod) (int) ((float)mod * (mt_random() / (RAND_MAX + 1.0)))
 #define MPRAND(add, mod) add + MRAND(mod)
diff --git a/src/ladmin/GNUmakefile b/src/ladmin/GNUmakefile
index 768626f..bed7b6b 100644
--- a/src/ladmin/GNUmakefile
+++ b/src/ladmin/GNUmakefile
@@ -2,8 +2,8 @@ all: ladmin
 txt: ladmin
 sql: ladmin
 
-COMMON_OBJ = ../common/core.o ../common/socket.o ../common/timer.o ../common/db.o ../common/malloc.o
-COMMON_H = ../common/core.h ../common/socket.h ../common/timer.h ../common/mmo.h ../common/version.h ../common/db.h ../common/malloc.h
+COMMON_OBJ = ../common/core.o ../common/socket.o ../common/timer.o ../common/db.o ../common/malloc.o ../common/mt_rand.o
+COMMON_H = ../common/core.h ../common/socket.h ../common/timer.h ../common/mmo.h ../common/version.h ../common/db.h ../common/malloc.h ../common/mt_rand.h
 
 ladmin: ladmin.o md5calc.o $(COMMON_OBJ)
 	$(CC) -o ../../$@ ladmin.o md5calc.o $(COMMON_OBJ)
diff --git a/src/ladmin/Makefile b/src/ladmin/Makefile
index 768626f..bed7b6b 100644
--- a/src/ladmin/Makefile
+++ b/src/ladmin/Makefile
@@ -2,8 +2,8 @@ all: ladmin
 txt: ladmin
 sql: ladmin
 
-COMMON_OBJ = ../common/core.o ../common/socket.o ../common/timer.o ../common/db.o ../common/malloc.o
-COMMON_H = ../common/core.h ../common/socket.h ../common/timer.h ../common/mmo.h ../common/version.h ../common/db.h ../common/malloc.h
+COMMON_OBJ = ../common/core.o ../common/socket.o ../common/timer.o ../common/db.o ../common/malloc.o ../common/mt_rand.o
+COMMON_H = ../common/core.h ../common/socket.h ../common/timer.h ../common/mmo.h ../common/version.h ../common/db.h ../common/malloc.h ../common/mt_rand.h
 
 ladmin: ladmin.o md5calc.o $(COMMON_OBJ)
 	$(CC) -o ../../$@ ladmin.o md5calc.o $(COMMON_OBJ)
diff --git a/src/login/Makefile b/src/login/Makefile
index d807238..0411129 100644
--- a/src/login/Makefile
+++ b/src/login/Makefile
@@ -1,8 +1,8 @@
 all: login-server
 txt: login-server
 
-COMMON_OBJ = ../common/core.o ../common/socket.o ../common/timer.o ../common/db.o ../common/lock.o ../common/malloc.o
-COMMON_H = ../common/core.h ../common/socket.h ../common/timer.h ../common/mmo.h ../common/version.h ../common/db.h ../common/lock.h ../common/malloc.h
+COMMON_OBJ = ../common/core.o ../common/socket.o ../common/timer.o ../common/db.o ../common/lock.o ../common/malloc.o ../common/mt_rand.o
+COMMON_H = ../common/core.h ../common/socket.h ../common/timer.h ../common/mmo.h ../common/version.h ../common/db.h ../common/lock.h ../common/malloc.h ../common/mt_rand.h
 
 login-server: login.o md5calc.o $(COMMON_OBJ)
 	$(CC) -o ../../$@ login.o md5calc.o $(COMMON_OBJ)
diff --git a/src/login/login.c b/src/login/login.c
index 6c4ca82..b44eb19 100644
--- a/src/login/login.c
+++ b/src/login/login.c
@@ -25,6 +25,7 @@
 #include "version.h"
 #include "db.h"
 #include "lock.h"
+#include "mt_rand.h"
 
 #ifdef PASSWORDENC
 #include "md5calc.h"
@@ -1153,8 +1154,8 @@ int mmo_auth(struct mmo_account* account, int fd) {
 	sprintf(tmpstr + strlen(tmpstr), ".%03d", (int)tv.tv_usec / 1000);
 
 	account->account_id = auth_dat[i].account_id;
-	account->login_id1 = rand();
-	account->login_id2 = rand();
+	account->login_id1 = mt_random();
+	account->login_id2 = mt_random();
 	memcpy(account->lastlogin, auth_dat[i].lastlogin, 24);
 	memcpy(auth_dat[i].lastlogin, tmpstr, 24);
 	account->sex = auth_dat[i].sex;
@@ -3785,8 +3786,6 @@ int do_init(int argc, char **argv) {
 	save_config_in_log(); // not before, because log file name can be changed
 	login_lan_config_read((argc > 1) ? argv[1] : LAN_CONF_NAME);
 
-	srand(time(NULL));
-
 	for(i = 0; i< AUTH_FIFO_SIZE; i++)
 		auth_fifo[i].delflag = 1;
 	for(i = 0; i < MAX_SERVERS; i++)
diff --git a/src/map/Makefile b/src/map/Makefile
index f02d43f..7fe6876 100644
--- a/src/map/Makefile
+++ b/src/map/Makefile
@@ -8,7 +8,7 @@ txt: obj map-server
 obj:
 	mkdir obj
 
-COMMON_OBJ = ../common/core.o ../common/socket.o ../common/timer.o ../common/grfio.o ../common/db.o ../common/lock.o ../common/nullpo.o ../common/malloc.o
+COMMON_OBJ = ../common/core.o ../common/socket.o ../common/timer.o ../common/grfio.o ../common/db.o ../common/lock.o ../common/nullpo.o ../common/malloc.o ../common/mt_rand.o
 LIBS = -lz -lm
 
 map-server: obj/tmw.o obj/magic-interpreter-lexer.o obj/magic-interpreter-parser.o obj/magic-interpreter-base.o obj/magic-expr.o obj/magic-stmt.o obj/magic.o obj/map.o obj/chrif.o obj/clif.o obj/pc.o obj/npc.o obj/chat.o obj/path.o obj/itemdb.o obj/mob.o obj/script.o obj/storage.o obj/skill.o obj/atcommand.o obj/battle.o obj/intif.o obj/trade.o obj/party.o obj/guild.o $(COMMON_OBJ)
diff --git a/src/map/atcommand.c b/src/map/atcommand.c
index de44d77..ed213b2 100644
--- a/src/map/atcommand.c
+++ b/src/map/atcommand.c
@@ -887,9 +887,9 @@ int atcommand_charwarp(
 	}
 
 	if (x <= 0)
-		x = rand() % 399 + 1;
+		x = MRAND(399) + 1;
 	if (y <= 0)
-		y = rand() % 399 + 1;
+		y = MRAND(399) + 1;
 	if (strstr(map_name, ".gat") == NULL && strstr(map_name, ".afm") == NULL && strlen(map_name) < 13) // 16 - 4 (.gat)
 		strcat(map_name, ".gat");
 
@@ -946,9 +946,9 @@ int atcommand_warp(const int fd, struct map_session_data* sd, const char* comman
 	}
 
 	if (x <= 0)
-		x = rand() % 399 + 1;
+		x = MRAND(399) + 1;
 	if (y <= 0)
-		y = rand() % 399 + 1;
+		y = MRAND(399) + 1;
 
 	if (strstr(map_name, ".gat") == NULL && strstr(map_name, ".afm") == NULL && strlen(map_name) < 13) // 16 - 4 (.gat)
 		strcat(map_name, ".gat");
@@ -1057,9 +1057,9 @@ int atcommand_jump(const int fd, struct map_session_data* sd, const char* comman
 	sscanf(message, "%d %d", &x, &y);
 
 	if (x <= 0)
-		x = rand() % 399 + 1;
+		x = MRAND(399) + 1;
 	if (y <= 0)
-		y = rand() % 399 + 1;
+		y = MRAND(399) + 1;
 	if (x > 0 && x < 400 && y > 0 && y < 400) {
 		if (sd->bl.m >= 0 && map[sd->bl.m].flag.nowarpto && battle_config.any_warp_GM_min_level > pc_isGM(sd)) {
 			clif_displaymessage(fd, "You are not authorised to warp you to your actual map.");
@@ -2537,11 +2537,11 @@ int atcommand_spawn(const int fd, struct map_session_data* sd, const char* comma
 		k = 0;
 		while(j++ < 8 && k == 0) { // try 8 times to spawn the monster (needed for close area)
 			if (x <= 0)
-				mx = sd->bl.x + (rand() % range - (range / 2));
+				mx = sd->bl.x + (MRAND(range) - (range / 2));
 			else
 				mx = x;
 			if (y <= 0)
-				my = sd->bl.y + (rand() % range - (range / 2));
+				my = sd->bl.y + (MRAND(range) - (range / 2));
 			else
 				my = y;
 			k = mob_once_spawn((struct map_session_data*)sd, "this", mx, my, "", mob_id, 1, "");
@@ -5461,7 +5461,7 @@ int atcommand_jail(
 
 	if ((pl_sd = map_nick2sd(character)) != NULL) {
 		if (pc_isGM(sd) >= pc_isGM(pl_sd)) { // you can jail only lower or same GM
-			switch(rand() % 2) {
+			switch(MRAND(2)) {
 			case 0:
 				x = 24;
 				y = 75;
@@ -6822,8 +6822,8 @@ int atcommand_summon(const int fd, struct map_session_data* sd, const char* comm
 	if(mob_id == 0)
 		return -1;
 
-	x = sd->bl.x + (rand() % 10 - 5);
-	y = sd->bl.y + (rand() % 10 - 5);
+	x = sd->bl.x + (MRAND(10) - 5);
+	y = sd->bl.y + (MRAND(10) - 5);
 
 	id = mob_once_spawn(sd,"this", x, y, "--ja--", mob_id, 1, "");
 	if((md=(struct mob_data *)map_id2bl(id))){
diff --git a/src/map/battle.c b/src/map/battle.c
index c21d69c..e424ef9 100644
--- a/src/map/battle.c
+++ b/src/map/battle.c
@@ -18,6 +18,7 @@
 #include "pc.h"
 #include "skill.h"
 #include "../common/socket.h"
+#include "mt_rand.h"
 
 #ifdef MEMWATCH
 #include "memwatch.h"
diff --git a/src/map/clif.c b/src/map/clif.c
index a53177d..aa7fea4 100644
--- a/src/map/clif.c
+++ b/src/map/clif.c
@@ -3369,9 +3369,9 @@ int clif_damage(struct block_list *src,struct block_list *dst,unsigned int tick,
 			type = 9;
 		if(sc_data[SC_HALLUCINATION].timer != -1) {
 			if(damage > 0)
-				damage = damage*(5+sc_data[SC_HALLUCINATION].val1) + rand()%100;
+				damage = damage*(5+sc_data[SC_HALLUCINATION].val1) + MRAND(100);
 			if(damage2 > 0)
-				damage2 = damage2*(5+sc_data[SC_HALLUCINATION].val1) + rand()%100;
+				damage2 = damage2*(5+sc_data[SC_HALLUCINATION].val1) + MRAND(100);
 		}
 	}
 
@@ -3881,7 +3881,7 @@ int clif_skill_damage(struct block_list *src,struct block_list *dst,
 		if(type != 5 && sc_data[SC_ENDURE].timer != -1)
 			type = 9;
 		if(sc_data[SC_HALLUCINATION].timer != -1 && damage > 0)
-			damage = damage*(5+sc_data[SC_HALLUCINATION].val1) + rand()%100;
+			damage = damage*(5+sc_data[SC_HALLUCINATION].val1) + MRAND(100);
 	}
 
 	WBUFW(buf,0)=0x1de;
@@ -3921,7 +3921,7 @@ int clif_skill_damage2(struct block_list *src,struct block_list *dst,
 		if(type != 5 && sc_data[SC_ENDURE].timer != -1)
 			type = 9;
 		if(sc_data[SC_HALLUCINATION].timer != -1 && damage > 0)
-			damage = damage*(5+sc_data[SC_HALLUCINATION].val1) + rand()%100;
+			damage = damage*(5+sc_data[SC_HALLUCINATION].val1) + MRAND(100);
 	}
 
 	WBUFW(buf,0)=0x115;
diff --git a/src/map/map.c b/src/map/map.c
index 86acb62..b3f9dd5 100644
--- a/src/map/map.c
+++ b/src/map/map.c
@@ -709,7 +709,7 @@ int map_searchrandfreecell(int m,int x,int y,int range) {
 	}
 	if(free_cell==0)
 		return -1;
-	free_cell=rand()%free_cell;
+	free_cell=MRAND(free_cell);
 	for(i=-range;i<=range;i++){
 		if(i+y<0 || i+y>=map[m].ys)
 			continue;
@@ -750,7 +750,7 @@ int map_addflooritem_any(struct item *item_data, int amount, int m, int x, int y
 
 	if((xy=map_searchrandfreecell(m,x,y, dispersal))<0)
 		return 0;
-	r=rand();
+	r=mt_random();
 
 	fitem = (struct flooritem_data *)aCalloc(1,sizeof(*fitem));
 	fitem->bl.type=BL_ITEM;
@@ -1833,8 +1833,6 @@ int do_init(int argc, char *argv[]) {
 	unsigned char *MSG_CONF_NAME = "conf/msg_athena.conf";
 	unsigned char *GRF_PATH_FILENAME = "conf/grf-files.txt";
 
-	srand(gettick());
-
 	for (i = 1; i < argc ; i++) {
 
 		if (strcmp(argv[i], "--help") == 0 || strcmp(argv[i], "--h") == 0 || strcmp(argv[i], "--?") == 0 || strcmp(argv[i], "/?") == 0)
diff --git a/src/map/pc.c b/src/map/pc.c
index d7c2b28..34cb59a 100644
--- a/src/map/pc.c
+++ b/src/map/pc.c
@@ -571,7 +571,7 @@ int pc_breakweapon(struct map_session_data *sd)
 
 	if(sd==NULL)
 		return -1;
-	if(sd->unbreakable>=rand()%100)
+	if(sd->unbreakable>=MRAND(100))
 		return 0;
 	if(sd->sc_data && sd->sc_data[SC_CP_WEAPON].timer != -1)
 		return 0;
@@ -608,7 +608,7 @@ int pc_breakarmor(struct map_session_data *sd)
 
 	if(sd==NULL)
 		return -1;
-	if(sd->unbreakable>=rand()%100)
+	if(sd->unbreakable>=MRAND(100))
 		return 0;
 	if(sd->sc_data && sd->sc_data[SC_CP_ARMOR].timer != -1)
 		return 0;
@@ -3399,8 +3399,8 @@ int pc_steal_coin(struct map_session_data *sd,struct block_list *bl)
 		if(md && !md->state.steal_coin_flag && md->sc_data && md->sc_data[SC_STONE].timer == -1 && md->sc_data[SC_FREEZE].timer == -1) {
 			skill = pc_checkskill(sd,RG_STEALCOIN)*10;
 			rate = skill + (sd->status.base_level - mob_db[md->class].lv)*3 + sd->paramc[4]*2 + sd->paramc[5]*2;
-			if(rand()%1000 < rate) {
-				pc_getzeny(sd,mob_db[md->class].lv*10 + rand()%100);
+			if(MRAND(1000) < rate) {
+				pc_getzeny(sd,mob_db[md->class].lv*10 + MRAND(100));
 				md->state.steal_coin_flag = 1;
 				return 1;
 			}
@@ -3515,8 +3515,8 @@ int pc_setpos(struct map_session_data *sd,char *mapname_org,int x,int y,int clrt
 				printf("stacked (%d,%d)\n",x,y);
 		}
 		do {
-			x=rand()%(map[m].xs-2)+1;
-			y=rand()%(map[m].ys-2)+1;
+			x=MRAND(map[m].xs-2)+1;
+			y=MRAND(map[m].ys-2)+1;
 		} while((c=read_gat(m,x,y))==1 || c==5);
 	}
 
@@ -3563,8 +3563,8 @@ int pc_randomwarp(struct map_session_data *sd, int type) {
 		return 0;
 
 	do{
-		x=rand()%(map[m].xs-2)+1;
-		y=rand()%(map[m].ys-2)+1;
+		x=MRAND(map[m].xs-2)+1;
+		y=MRAND(map[m].ys-2)+1;
 	} while (((c=read_gat(m,x,y)) == 1 || c == 5) && (i++) < 1000);
 
 	if (i < 1000)
@@ -5099,8 +5099,8 @@ int pc_damage(struct block_list *src,struct map_session_data *sd,int damage)
 					}
 				}
 				if(eq_num > 0){
-					int n = eq_n[rand()%eq_num];//�Y���A�C�e���̒����烉���_��
-					if(rand()%10000 < per){
+					int n = eq_n[MRAND(eq_num)];//�Y���A�C�e���̒����烉���_��
+					if(MRAND(10000) < per){
 						if(sd->status.inventory[n].equip)
 							pc_unequipitem(sd,n,0);
 						pc_dropitem(sd,n,1);
@@ -5110,7 +5110,7 @@ int pc_damage(struct block_list *src,struct map_session_data *sd,int damage)
 			else if(id > 0){
 				for(i=0;i<MAX_INVENTORY;i++){
 					if(sd->status.inventory[i].nameid == id//ItemID�����v������
-						&& rand()%10000 < per//�h���b�v��������OK��
+						&& MRAND(10000) < per//�h���b�v��������OK��
 						&& ((type == 1 && !sd->status.inventory[i].equip)//�^�C�v������OK�Ȃ��h���b�v
 							|| (type == 2 && sd->status.inventory[i].equip)
 							|| type == 3) ){
diff --git a/src/map/skill.c b/src/map/skill.c
index c661dc2..0539f9a 100644
--- a/src/map/skill.c
+++ b/src/map/skill.c
@@ -943,13 +943,13 @@ int skill_additional_effect( struct block_list* src, struct block_list *bl,int s
 	case 0:					/* �ʏ�U�� */
 		/* ������ */
 		if( sd && pc_isfalcon(sd) && sd->status.weapon == 11 && (skill=pc_checkskill(sd,HT_BLITZBEAT))>0 &&
-			rand()%1000 <= sd->paramc[5]*10/3+1 ) {
+			MRAND(1000) <= sd->paramc[5]*10/3+1 ) {
 			int lv=(sd->status.job_level+9)/10;
 			skill_castend_damage_id(src,bl,HT_BLITZBEAT,(skill<lv)?skill:lv,tick,0xf00000);
 		}
 		// �X�i�b�`���[
 		if(sd && sd->status.weapon != 11 && (skill=pc_checkskill(sd,RG_SNATCHER)) > 0)
-			if((skill*15 + 55) + (skill2 = pc_checkskill(sd,TF_STEAL))*10 > rand()%1000) {
+			if((skill*15 + 55) + (skill2 = pc_checkskill(sd,TF_STEAL))*10 > MRAND(1000)) {
 				if(pc_steal_item(sd,bl))
 					clif_skill_nodamage(src,bl,TF_STEAL,skill2,1);
 				else
@@ -959,14 +959,14 @@ int skill_additional_effect( struct block_list* src, struct block_list *bl,int s
 
 	case SM_BASH:			/* �o�b�V���i�}���U���j */
 		if( sd && (skill=pc_checkskill(sd,SM_FATALBLOW))>0 ){
-			if( rand()%100 < 6*(skilllv-5)*sc_def_vit/100 )
+			if(MRAND(100) < 6*(skilllv-5)*sc_def_vit/100 )
 				skill_status_change_start(bl,SC_STAN,skilllv,0,0,0,skill_get_time2(SM_FATALBLOW,skilllv),0);
 		}
 		break;
 
 	case TF_POISON:			/* �C���x�i�� */
 	case AS_SPLASHER:		/* �x�i���X�v���b�V���[ */
-		if(rand()%100< (2*skilllv+10)*sc_def_vit/100 )
+		if(MRAND(100) < (2*skilllv+10)*sc_def_vit/100 )
 			skill_status_change_start(bl,SC_POISON,skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);
 		else{
 			if(sd && skillid==TF_POISON)
@@ -975,14 +975,14 @@ int skill_additional_effect( struct block_list* src, struct block_list *bl,int s
 		break;
 
 	case AS_SONICBLOW:		/* �\�j�b�N�u���[ */
-		if( rand()%100 < (2*skilllv+10)*sc_def_vit/100 )
+		if(MRAND(100) < (2*skilllv+10)*sc_def_vit/100 )
 			skill_status_change_start(bl,SC_STAN,skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);
 		break;
 
 
 	case HT_FREEZINGTRAP:	/* �t���[�W���O�g���b�v */
 		rate=skilllv*3+35;
-		if(rand()%100 < rate*sc_def_mdef/100)
+		if(MRAND(100) < rate*sc_def_mdef/100)
 			skill_status_change_start(bl,SC_FREEZE,skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);
 		break;
 
@@ -990,7 +990,7 @@ int skill_additional_effect( struct block_list* src, struct block_list *bl,int s
 	case WZ_FROSTNOVA:		/* �t���X�g�m���@ */
 		rate=(skilllv*3+35)*sc_def_mdef/100-(battle_get_int(bl)+battle_get_luk(bl))/15;
 		rate=rate<=5?5:rate;
-		if(rand()%100 < rate)
+		if(MRAND(100) < rate)
 			skill_status_change_start(bl,SC_FREEZE,skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);
 		else if(sd)
 			clif_skill_fail(sd,skillid,0,0);
@@ -1008,7 +1008,7 @@ int skill_additional_effect( struct block_list* src, struct block_list *bl,int s
 		break;
 
 	case HT_LANDMINE:		/* �����h�}�C�� */
-		if( rand()%100 < (5*skilllv+30)*sc_def_vit/100 )
+		if( MRAND(100) < (5*skilllv+30)*sc_def_vit/100 )
 			skill_status_change_start(bl,SC_STAN,skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);
 		break;
 
@@ -1019,62 +1019,62 @@ int skill_additional_effect( struct block_list* src, struct block_list *bl,int s
 		}
 		break;
 	case HT_SANDMAN:		/* �T���h�}�� */
-		if( rand()%100 < (5*skilllv+30)*sc_def_int/100 )
+		if( MRAND(100) < (5*skilllv+30)*sc_def_int/100 )
 			skill_status_change_start(bl,SC_SLEEP,skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);
 		break;
 	case TF_SPRINKLESAND:	/* ���܂� */
-		if( rand()%100 < 15*sc_def_int/100 )
+		if( MRAND(100) < 15*sc_def_int/100 )
 			skill_status_change_start(bl,SC_BLIND,skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);
 		break;
 
 	case TF_THROWSTONE:		/* ���� */
-		if( rand()%100 < 5*sc_def_vit/100 )
+		if( MRAND(100) < 5*sc_def_vit/100 )
 			skill_status_change_start(bl,SC_STAN,skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);
 		break;
 
 	case CR_HOLYCROSS:		/* �z�[���[�N���X */
-		if( rand()%100 < 3*skilllv*sc_def_int/100 )
+		if( MRAND(100) < 3*skilllv*sc_def_int/100 )
 			skill_status_change_start(bl,SC_BLIND,skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);
 		break;
 
 	case CR_GRANDCROSS:		/* �O�����h�N���X */
 		{
 			int race = battle_get_race(bl);
-			if( (battle_check_undead(race,battle_get_elem_type(bl)) || race == 6) && rand()%100 < 100000*sc_def_int/100)	//�����t�^�������S�ϐ��ɂ͖���
+			if( (battle_check_undead(race,battle_get_elem_type(bl)) || race == 6) && MRAND(100) < 100000*sc_def_int/100)	//�����t�^�������S�ϐ��ɂ͖���
 				skill_status_change_start(bl,SC_BLIND,skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);
 		}
 		break;
 
 	case CR_SHIELDCHARGE:		/* �V�[���h�`���[�W */
-		if( rand()%100 < (15 + skilllv*5)*sc_def_vit/100 )
+		if( MRAND(100) < (15 + skilllv*5)*sc_def_vit/100 )
 			skill_status_change_start(bl,SC_STAN,skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);
 		break;
 
 	case RG_RAID:		/* �T�v���C�Y�A�^�b�N */
-		if( rand()%100 < (10+3*skilllv)*sc_def_vit/100 )
+		if( MRAND(100) < (10+3*skilllv)*sc_def_vit/100 )
 			skill_status_change_start(bl,SC_STAN,skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);
-		if( rand()%100 < (10+3*skilllv)*sc_def_int/100 )
+		if( MRAND(100) < (10+3*skilllv)*sc_def_int/100 )
 			skill_status_change_start(bl,SC_BLIND,skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);
 		break;
 	case BA_FROSTJOKE:
-		if(rand()%100 < (15+5*skilllv)*sc_def_mdef/100)
+		if(MRAND(100) < (15+5*skilllv)*sc_def_mdef/100)
 			skill_status_change_start(bl,SC_FREEZE,skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);
 		break;
 
 	case DC_SCREAM:
-		if( rand()%100 < (25+5*skilllv)*sc_def_vit/100 )
+		if( MRAND(100) < (25+5*skilllv)*sc_def_vit/100 )
 			skill_status_change_start(bl,SC_STAN,skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);
 		break;
 
 	case BD_LULLABY:	/* �q��S */
-		if( rand()%100 < 15*sc_def_int/100 )
+		if( MRAND(100) < 15*sc_def_int/100 )
 			skill_status_change_start(bl,SC_SLEEP,skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);
 		break;
 
 	/* MOB�̒lj����ʕt���X�L�� */
 
 	case NPC_PETRIFYATTACK:
-		if(rand()%100 < sc_def_mdef)
+		if(MRAND(100) < sc_def_mdef)
 			skill_status_change_start(bl,sc[skillid-NPC_POISON],skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);
 		break;
 	case NPC_POISON:
@@ -1084,12 +1084,12 @@ int skill_additional_effect( struct block_list* src, struct block_list *bl,int s
 			skill_status_change_start(bl,sc[skillid-NPC_POISON],skilllv,0,0,0,skilllv,0);
 		break;
 	case NPC_CURSEATTACK:
-		if(rand()%100 < sc_def_luk)
+		if(MRAND(100) < sc_def_luk)
 			skill_status_change_start(bl,sc[skillid-NPC_POISON],skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);
 		break;
 	case NPC_SLEEPATTACK:
 	case NPC_BLINDATTACK:
-		if(rand()%100 < sc_def_int)
+		if(MRAND(100) < sc_def_int)
 			skill_status_change_start(bl,sc[skillid-NPC_POISON],skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);
 		break;
 	case NPC_MENTALBREAKER:
@@ -1103,43 +1103,43 @@ int skill_additional_effect( struct block_list* src, struct block_list *bl,int s
 // -- moonsoul (adding status effect chance given to wizard aoe skills meteor and vermillion)
 //
 	case WZ_METEOR:
-		if(rand()%100 < sc_def_vit)
+		if(MRAND(100) < sc_def_vit)
 			skill_status_change_start(bl,SC_STAN,skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);		
 		break;
 	case WZ_VERMILION:
-		if(rand()%100 < sc_def_int)
+		if(MRAND(100) < sc_def_int)
 			skill_status_change_start(bl,SC_BLIND,skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);		
 		break;
 
 // -- moonsoul (stun ability of new champion skill tigerfist)
 //
 	case CH_TIGERFIST:
-		if( rand()%100 < (5 + skilllv*5)*sc_def_vit/100 )
+		if( MRAND(100) < (5 + skilllv*5)*sc_def_vit/100 )
 			skill_status_change_start(bl,SC_STAN,skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);
 		break;
 
 	case LK_SPIRALPIERCE:
-		if( rand()%100 < (15 + skilllv*5)*sc_def_vit/100 )
+		if( MRAND(100) < (15 + skilllv*5)*sc_def_vit/100 )
 			skill_status_change_start(bl,SC_STAN,skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);
 		break;
 	case ST_REJECTSWORD:	/* �t���[�W���O�g���b�v */
-		if( rand()%100 < (10 + skilllv*5) )
+		if( MRAND(100) < (10 + skilllv*5) )
 			skill_status_change_start(bl,SC_AUTOCOUNTER,skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);
 		break;
 	case PF_FOGWALL:		/* �z�[���[�N���X */
-		if( rand()%100 < 3*skilllv*sc_def_int/100 )
+		if( MRAND(100) < 3*skilllv*sc_def_int/100 )
 			skill_status_change_start(bl,SC_BLIND,skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);
 		break;
 	case LK_HEADCRUSH:				/* �w�b�h�N���b�V�� */
 		{//�������ǂ�������Ȃ��̂œK����
 			int race=battle_get_race(bl);
-			if( !(battle_check_undead(race,battle_get_elem_type(bl)) || race == 6) && rand()%100 < (2*skilllv+10)*sc_def_vit/100 )
+			if( !(battle_check_undead(race,battle_get_elem_type(bl)) || race == 6) && MRAND(100) < (2*skilllv+10)*sc_def_vit/100 )
 				skill_status_change_start(bl,SC_HEADCRUSH,skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);
 		}
 			break;
 	case LK_JOINTBEAT:				/* �W���C���g�r�[�g */
 		//�������ǂ�������Ȃ��̂œK����
-		if( rand()%100 < (2*skilllv+10)*sc_def_vit/100 )
+		if( MRAND(100) < (2*skilllv+10)*sc_def_vit/100 )
 			skill_status_change_start(bl,SC_JOINTBEAT,skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);
 		break;
 	case PF_SPIDERWEB:		/* �X�p�C�_�[�E�F�b�u */
@@ -1152,9 +1152,9 @@ int skill_additional_effect( struct block_list* src, struct block_list *bl,int s
 		}
 		break;
 	case ASC_METEORASSAULT:			/* ���e�I�A�T���g */
-		if( rand()%100 < (15 + skilllv*5)*sc_def_vit/100 ) //��Ԉُ�͏ڍׂ�������Ȃ��̂œK����
+		if( MRAND(100) < (15 + skilllv*5)*sc_def_vit/100 ) //��Ԉُ�͏ڍׂ�������Ȃ��̂œK����
 			skill_status_change_start(bl,SC_STAN,skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);
-		if( rand()%100 < (10+3*skilllv)*sc_def_int/100 )
+		if( MRAND(100) < (10+3*skilllv)*sc_def_int/100 )
 			skill_status_change_start(bl,SC_BLIND,skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);
 		break;
 	case MO_EXTREMITYFIST:			/* ���C���e���� */
@@ -1179,14 +1179,14 @@ int skill_additional_effect( struct block_list* src, struct block_list *bl,int s
 				sc_def_card=sc_def_luk;
 
 			if(!sd->state.arrow_atk) {
-				if(rand()%10000 < (sd->addeff[i-SC_STONE])*sc_def_card/100 ){
+				if(MRAND(100) < (sd->addeff[i-SC_STONE])*sc_def_card/100 ){
 					if(battle_config.battle_log)
 						printf("PC %d skill_addeff: card�ɂ��ُ픭�� %d %d\n",sd->bl.id,i,sd->addeff[i-SC_STONE]);
 					skill_status_change_start(bl,i,7,0,0,0,(i==SC_CONFUSION)? 10000+7000:skill_get_time2(sc2[i-SC_STONE],7),0);
 				}
 			}
 			else {
-				if(rand()%10000 < (sd->addeff[i-SC_STONE]+sd->arrow_addeff[i-SC_STONE])*sc_def_card/100 ){
+				if(MRAND(100) < (sd->addeff[i-SC_STONE]+sd->arrow_addeff[i-SC_STONE])*sc_def_card/100 ){
 					if(battle_config.battle_log)
 						printf("PC %d skill_addeff: card�ɂ��ُ픭�� %d %d\n",sd->bl.id,i,sd->addeff[i-SC_STONE]);
 					skill_status_change_start(bl,i,7,0,0,0,(i==SC_CONFUSION)? 10000+7000:skill_get_time2(sc2[i-SC_STONE],7),0);
@@ -1203,14 +1203,14 @@ int skill_additional_effect( struct block_list* src, struct block_list *bl,int s
 				sc_def_card=sc_def_luk2;
 
 			if(!sd->state.arrow_atk) {
-				if(rand()%10000 < (sd->addeff2[i-SC_STONE])*sc_def_card/100 ){
+				if(MRAND(100) < (sd->addeff2[i-SC_STONE])*sc_def_card/100 ){
 					if(battle_config.battle_log)
 						printf("PC %d skill_addeff: card�ɂ��ُ픭�� %d %d\n",src->id,i,sd->addeff2[i-SC_STONE]);
 					skill_status_change_start(src,i,7,0,0,0,(i==SC_CONFUSION)? 10000+7000:skill_get_time2(sc2[i-SC_STONE],7),0);
 				}
 			}
 			else {
-				if(rand()%10000 < (sd->addeff2[i-SC_STONE]+sd->arrow_addeff2[i-SC_STONE])*sc_def_card/100 ){
+				if(MRAND(100) < (sd->addeff2[i-SC_STONE]+sd->arrow_addeff2[i-SC_STONE])*sc_def_card/100 ){
 					if(battle_config.battle_log)
 						printf("PC %d skill_addeff: card�ɂ��ُ픭�� %d %d\n",src->id,i,sd->addeff2[i-SC_STONE]);
 					skill_status_change_start(src,i,7,0,0,0,(i==SC_CONFUSION)? 10000+7000:skill_get_time2(sc2[i-SC_STONE],7),0);
@@ -1564,7 +1564,7 @@ int skill_attack( int attack_type, struct block_list* src, struct block_list *ds
 		int s_lv = battle_get_lv(src),t_lv = battle_get_lv(bl);
 		int rate = 50 + skilllv * 5;
 		rate = rate + (s_lv - t_lv);
-		if(rand()%100 < rate)
+		if(MRAND(100) < rate)
 			skill_addtimerskill(src,tick + 800,bl->id,0,0,skillid,skilllv,0,flag);
 	}
 	if(damage > 0 && dmg.flag&BF_SKILL && bl->type==BL_PC && pc_checkskill((struct map_session_data *)bl,RG_PLAGIARISM)){
@@ -1617,22 +1617,22 @@ int skill_attack( int attack_type, struct block_list* src, struct block_list *ds
 		struct map_session_data *sd = (struct map_session_data *)src;
 		int hp = 0,sp = 0;
 		nullpo_retr(0, sd);
-		if(sd->hp_drain_rate && sd->hp_drain_per > 0 && dmg.damage > 0 && rand()%100 < sd->hp_drain_rate) {
+		if(sd->hp_drain_rate && sd->hp_drain_per > 0 && dmg.damage > 0 && MRAND(100) < sd->hp_drain_rate) {
 			hp += (dmg.damage * sd->hp_drain_per)/100;
 			if(sd->hp_drain_rate > 0 && hp < 1) hp = 1;
 			else if(sd->hp_drain_rate < 0 && hp > -1) hp = -1;
 		}
-		if(sd->hp_drain_rate_ && sd->hp_drain_per_ > 0 && dmg.damage2 > 0 && rand()%100 < sd->hp_drain_rate_) {
+		if(sd->hp_drain_rate_ && sd->hp_drain_per_ > 0 && dmg.damage2 > 0 && MRAND(100) < sd->hp_drain_rate_) {
 			hp += (dmg.damage2 * sd->hp_drain_per_)/100;
 			if(sd->hp_drain_rate_ > 0 && hp < 1) hp = 1;
 			else if(sd->hp_drain_rate_ < 0 && hp > -1) hp = -1;
 		}
-		if(sd->sp_drain_rate > 0 && sd->sp_drain_per > 0 && dmg.damage > 0 && rand()%100 < sd->sp_drain_rate) {
+		if(sd->sp_drain_rate > 0 && sd->sp_drain_per > 0 && dmg.damage > 0 && MRAND(100) < sd->sp_drain_rate) {
 			sp += (dmg.damage * sd->sp_drain_per)/100;
 			if(sd->sp_drain_rate > 0 && sp < 1) sp = 1;
 			else if(sd->sp_drain_rate < 0 && sp > -1) sp = -1;
 		}
-		if(sd->sp_drain_rate_ > 0 && sd->sp_drain_per_ > 0 && dmg.damage2 > 0 && rand()%100 < sd->sp_drain_rate_) {
+		if(sd->sp_drain_rate_ > 0 && sd->sp_drain_per_ > 0 && dmg.damage2 > 0 && MRAND(100) < sd->sp_drain_rate_) {
 			sp += (dmg.damage2 * sd->sp_drain_per_)/100;
 			if(sd->sp_drain_rate_ > 0 && sp < 1) sp = 1;
 			else if(sd->sp_drain_rate_ < 0 && sp > -1) sp = -1;
@@ -1865,7 +1865,7 @@ static int skill_timerskill(int tid, unsigned int tick, int id,int data )
 					int x,y,i,j,c;
 					pc_randomwarp(sd,3);
 					for(i=0;i<16;i++) {
-						j = rand()%8;
+						j = MRAND(8);
 						x = sd->bl.x + dirx[j];
 						y = sd->bl.y + diry[j];
 						if((c=map_getcell(sd->bl.m,x,y)) != 1 && c != 5)
@@ -1886,7 +1886,7 @@ static int skill_timerskill(int tid, unsigned int tick, int id,int data )
 					int x,y,i,j,c;
 					mob_warp(md,-1,-1,-1,3);
 					for(i=0;i<16;i++) {
-						j = rand()%8;
+						j = MRAND(8);
 						x = md->bl.x + dirx[j];
 						y = md->bl.y + diry[j];
 						if((c=map_getcell(md->bl.m,x,y)) != 1 && c != 5)
@@ -2163,7 +2163,7 @@ int skill_castend_damage_id( struct block_list* src, struct block_list *bl,int s
 
 	case AM_ACIDTERROR:		/* �A�V�b�h�e���[ */
 		skill_attack(BF_WEAPON,src,src,bl,skillid,skilllv,tick,flag);
-		if(bl->type == BL_PC && rand()%100 < skill_get_time(skillid,skilllv) && battle_config.equipment_breaking)
+		if(bl->type == BL_PC && MRAND(100) < skill_get_time(skillid,skilllv) && battle_config.equipment_breaking)
 			pc_breakarmor((struct map_session_data *)bl);
 		break;
 	case MO_FINGEROFFENSIVE:	/* �w�e */
@@ -2692,7 +2692,7 @@ int skill_castend_nodamage_id( struct block_list *src, struct block_list *bl,int
 	case AL_DECAGI:			/* ���x���� */
 		if( bl->type==BL_PC && ((struct map_session_data *)bl)->special_state.no_magic_damage )
 			break;
-		if( rand()%100 < (50+skilllv*3+(battle_get_lv(src)+battle_get_int(src)/5)-sc_def_mdef) ) {
+		if( MRAND(100) < (50+skilllv*3+(battle_get_lv(src)+battle_get_int(src)/5)-sc_def_mdef) ) {
 			clif_skill_nodamage(src,bl,skillid,skilllv,1);
 			skill_status_change_start(bl,SkillStatusChangeTable[skillid],skilllv,0,0,0,skill_get_time(skillid,skilllv),0);
 		}
@@ -2704,7 +2704,7 @@ int skill_castend_nodamage_id( struct block_list *src, struct block_list *bl,int
 			if(battle_check_target(src,bl,BCT_ENEMY) && (race == 6 || battle_check_undead(race,ele))) {
 				int slv=battle_get_lv(src),tlv=battle_get_lv(bl),rate;
 				rate = 25 + skilllv*2 + slv - tlv;
-				if(rand()%100 < rate)
+				if(MRAND(100) < rate)
 					skill_status_change_start(bl,SkillStatusChangeTable[skillid],skilllv,0,0,0,0,0);
 			}
 		}
@@ -2726,7 +2726,7 @@ int skill_castend_nodamage_id( struct block_list *src, struct block_list *bl,int
 				break;
 			if(sc_data && sc_data[SC_DIVINA].timer != -1)
 				skill_status_change_end(bl,SC_DIVINA,-1);
-			else if( rand()%100 < sc_def_vit ) {
+			else if( MRAND(100) < sc_def_vit ) {
 				skill_status_change_start(bl,SkillStatusChangeTable[skillid],skilllv,0,0,0,skill_get_time(skillid,skilllv),0);
 			}
 		}
@@ -2826,7 +2826,7 @@ int skill_castend_nodamage_id( struct block_list *src, struct block_list *bl,int
 				break;
 			}
 		}
-		if(rand()%100 > (75+skilllv*1) && (skilllv != 5)) {
+		if(MRAND(100) > (75+skilllv*1) && (skilllv != 5)) {
 			clif_skill_fail(sd,skillid,0,0);
 			clif_skill_nodamage(src,bl,skillid,skilllv,0);
 			if(bl->type==BL_PC && battle_config.equipment_breaking) {
@@ -3021,7 +3021,7 @@ int skill_castend_nodamage_id( struct block_list *src, struct block_list *bl,int
 			}
 		}else if(sd && dstmd){ //�Ώۂ������X�^�[�̏ꍇ
 			//20%�̊m���őΏۂ�Lv*2��SP���񕜂���B���������Ƃ��̓^�[�Q�b�g(��߄D�)�йޯ�!!
-			if(rand()%100<20){
+			if(MRAND(100)<20){
 				i=2*mob_db[dstmd->class].lv;
 				mob_target(dstmd,src,0);
 			}
@@ -3063,7 +3063,7 @@ int skill_castend_nodamage_id( struct block_list *src, struct block_list *bl,int
 		clif_skill_nodamage(src,bl,skillid,skilllv,1);
 		if( bl->type==BL_PC && ((struct map_session_data *)bl)->special_state.no_weapon_damage )
 			break;
-		if( rand()%100 < (20+ 10*skilllv)*sc_def_vit/100 ) {
+		if( MRAND(100) < (20+ 10*skilllv)*sc_def_vit/100 ) {
 			skill_status_change_start(bl,SC_STAN,skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);
 		}
 		break;
@@ -3318,7 +3318,7 @@ int skill_castend_nodamage_id( struct block_list *src, struct block_list *bl,int
 		clif_skill_nodamage(src,bl,skillid,skilllv,1);
 		if( bl->type==BL_PC && ((struct map_session_data *)bl)->special_state.no_magic_damage )
 			break;
-		if( rand()%100 < skilllv*4+20 && !battle_check_undead(battle_get_race(bl),battle_get_elem_type(bl)))
+		if( MRAND(100) < skilllv*4+20 && !battle_check_undead(battle_get_race(bl),battle_get_elem_type(bl)))
 			skill_status_change_start(bl,SC_STONE,skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);
 		else if(sd)
 			clif_skill_fail(sd,skillid,0,0);
@@ -3359,7 +3359,7 @@ int skill_castend_nodamage_id( struct block_list *src, struct block_list *bl,int
 				int blind_time;
 				//blind_time=30-battle_get_vit(bl)/10-battle_get_int/15;
 				blind_time=30*(100-(battle_get_int(bl)+battle_get_vit(bl))/2)/100;
-				if(rand()%100 < (100-(battle_get_int(bl)/2+battle_get_vit(bl)/3+battle_get_luk(bl)/10)))
+				if(MRAND(100) < (100-(battle_get_int(bl)/2+battle_get_vit(bl)/3+battle_get_luk(bl)/10)))
 					skill_status_change_start(bl, SC_BLIND,1,0,0,0,blind_time,0);
 			}
 			if(dstmd){
@@ -3367,7 +3367,7 @@ int skill_castend_nodamage_id( struct block_list *src, struct block_list *bl,int
 				dstmd->target_id=0;
 				dstmd->state.targettype = NONE_ATTACKABLE;
 				dstmd->state.skillstate=MSS_IDLE;
-				dstmd->next_walktime=tick+rand()%3000+3000;
+				dstmd->next_walktime=tick+MRAND(3000)+3000;
 			}
 		}
 		break;
@@ -3455,7 +3455,7 @@ int skill_castend_nodamage_id( struct block_list *src, struct block_list *bl,int
 			break;
 		strip_per = 5+2*skilllv+strip_fix/5;
 		strip_time = skill_get_time(skillid,skilllv)+strip_fix/2;
-		if(rand()%100 < strip_per){
+		if(MRAND(100) < strip_per){
 			clif_skill_nodamage(src,bl,skillid,skilllv,1);
 			skill_status_change_start(bl,SkillStatusChangeTable[skillid],skilllv,0,0,0,strip_time,0 );
 			if(dstsd){
@@ -3478,7 +3478,7 @@ int skill_castend_nodamage_id( struct block_list *src, struct block_list *bl,int
 			break;
 		strip_per = 5+2*skilllv+strip_fix/5;
 		strip_time = skill_get_time(skillid,skilllv)+strip_fix/2;
-		if(rand()%100 < strip_per){
+		if(MRAND(100) < strip_per){
 			clif_skill_nodamage(src,bl,skillid,skilllv,1);
 			skill_status_change_start(bl,SkillStatusChangeTable[skillid],skilllv,0,0,0,strip_time,0 );
 			if(dstsd){
@@ -3501,7 +3501,7 @@ int skill_castend_nodamage_id( struct block_list *src, struct block_list *bl,int
 			break;
 		strip_per = 5+2*skilllv+strip_fix/5;
 		strip_time = skill_get_time(skillid,skilllv)+strip_fix/2;
-		if(rand()%100 < strip_per){
+		if(MRAND(100) < strip_per){
 			clif_skill_nodamage(src,bl,skillid,skilllv,1);
 			skill_status_change_start(bl,SkillStatusChangeTable[skillid],skilllv,0,0,0,strip_time,0 );
 			if(dstsd){
@@ -3523,7 +3523,7 @@ int skill_castend_nodamage_id( struct block_list *src, struct block_list *bl,int
 			break;
 		strip_per = 5+2*skilllv+strip_fix/5;
 		strip_time = skill_get_time(skillid,skilllv)+strip_fix/2;
-		if(rand()%100 < strip_per){
+		if(MRAND(100) < strip_per){
 			clif_skill_nodamage(src,bl,skillid,skilllv,1);
 			skill_status_change_start(bl,SkillStatusChangeTable[skillid],skilllv,0,0,0,strip_time,0 );
 			if(dstsd){
@@ -3589,7 +3589,7 @@ int skill_castend_nodamage_id( struct block_list *src, struct block_list *bl,int
 				}
 			}
 			else {
-				hp = (1 + rand()%400) * (100 + skilllv*10) / 100;
+				hp = (1 + MRAND(400)) * (100 + skilllv*10) / 100;
 				hp = hp * (100 + (battle_get_vit(bl)<<1)) / 100;
 				if(dstsd)
 					hp = hp * (100 + pc_checkskill(dstsd,SM_RECOVERY)*10) / 100;
@@ -3768,7 +3768,7 @@ int skill_castend_nodamage_id( struct block_list *src, struct block_list *bl,int
 				maxlv = skilllv - 4;
 			}
 			else if(skilllv >=2) {
-				int i = rand()%3;
+				int i = MRAND(3);
 				spellid = spellarray[i];
 				maxlv = skilllv - 1;
 			}
@@ -3797,8 +3797,8 @@ int skill_castend_nodamage_id( struct block_list *src, struct block_list *bl,int
 			clif_skill_nodamage(src,bl,skillid,skilllv,1);
 			md->def_ele=skill_get_pl(skillid);
 			if(md->def_ele==0)			/* �����_���ω��A�������A*/
-				md->def_ele=rand()%10;	/* �s�������͏��� */
-			md->def_ele+=(1+rand()%4)*20;	/* �������x���̓����_�� */
+				md->def_ele=MRAND(10);	/* �s�������͏��� */
+			md->def_ele+=(1+MRAND(4))*20;	/* �������x���̓����_�� */
 		}
 		break;
 
@@ -3827,7 +3827,7 @@ int skill_castend_nodamage_id( struct block_list *src, struct block_list *bl,int
 				break;
 			if(battle_get_elem_type(bl) == 7 || battle_get_race(bl) == 6)
 				break;
-			if(rand()%100 < sc_def*(50+skilllv*5)/100) {
+			if(MRAND(100) < sc_def*(50+skilllv*5)/100) {
 				if(dstsd) {
 					int hp = battle_get_hp(bl)-1;
 					pc_heal(dstsd,-hp,0);
@@ -3848,7 +3848,7 @@ int skill_castend_nodamage_id( struct block_list *src, struct block_list *bl,int
 			break;
 		if(dstsd)
 			pc_heal(dstsd,0,-100);
-		if(rand()%100 < (skilllv*5)*sc_def_vit/100)
+		if(MRAND(100) < (skilllv*5)*sc_def_vit/100)
 			skill_status_change_start(bl,SC_STAN,skilllv,0,0,0,skill_get_time2(skillid,skilllv),0);
 		break;
 
@@ -4313,8 +4313,8 @@ int skill_castend_pos2( struct block_list *src, int x,int y,int skillid,int skil
 			for(i=0;i<2+(skilllv>>1);i++) {
 				int j=0, c;
 				do {
-					tmpx = x + (rand()%7 - 3);
-					tmpy = y + (rand()%7 - 3);
+					tmpx = x + (MRAND(7) - 3);
+					tmpy = y + (MRAND(7) - 3);
 					if(tmpx < 0)
 						tmpx = 0;
 					else if(tmpx >= map[src->m].xs)
@@ -5346,7 +5346,7 @@ int skill_unit_onplace(struct skill_unit *src,struct block_list *bl,unsigned int
 
 	case 0xb1:	/* �f�����X�g���[�V���� */
 		skill_attack(BF_WEAPON,ss,&src->bl,bl,sg->skill_id,sg->skill_lv,tick,0);
-		if(bl->type == BL_PC && rand()%100 < sg->skill_lv && battle_config.equipment_breaking)
+		if(bl->type == BL_PC && MRAND(100) < sg->skill_lv && battle_config.equipment_breaking)
 			pc_breakweapon((struct map_session_data *)bl);
 		break;
 	case 0x99:				/* �g�[�L�[�{�b�N�X */
@@ -7268,7 +7268,7 @@ int skill_frostjoke_scream(struct block_list *bl,va_list ap)
 	if(battle_check_target(src,bl,BCT_ENEMY) > 0)
 		skill_additional_effect(src,bl,skillnum,skilllv,BF_MISC,tick);
 	else if(battle_check_target(src,bl,BCT_PARTY) > 0) {
-		if(rand()%100 < 10)//PT�����o�ɂ���m���ł�����(�Ƃ肠����10%)
+		if(MRAND(100) < 10)//PT�����o�ɂ���m���ł�����(�Ƃ肠����10%)
 			skill_additional_effect(src,bl,skillnum,skilllv,BF_MISC,tick);
 	}
 
@@ -8274,7 +8274,7 @@ int skill_status_effect(struct block_list *bl, int type, int val1, int val2, int
 			return 0;
 
 		if(SC_STONE<=type && type<=SC_BLIND){	/* �J�[�h�ɂ��ϐ� */
-			if( sd && sd->reseff[type-SC_STONE] > 0 && rand()%10000<sd->reseff[type-SC_STONE]){
+			if( sd && sd->reseff[type-SC_STONE] > 0 && MRAND(100)<sd->reseff[type-SC_STONE]){
 				if(battle_config.battle_log)
 					printf("PC %d skill_sc_start: card�ɂ��ُ�ϐ�����\n",sd->bl.id);
 				return 0;