sema.patch

MINIX操作系统的内核修改补丁

+ #include "proto.h"
+ #include "glo.h"
+ #include "semaphore.h"
+ 
diff -c -Nr src.clean/servers/ss/main.c src/servers/ss/main.c
*** src.clean/servers/ss/main.c	1970-01-01 08:00:00.000000000 +0800
--- src/servers/ss/main.c	2008-11-16 04:34:00.000000000 +0800
***************
*** 0 ****
--- 1,145 ----
+ /* Data Semaphore Server.*/
+ 
+ #include "inc.h"	/* include master header file */
+ 
+ /* Allocate space for the global variables. */
+ int who_e;		/* caller's proc number */
+ int callnr;		/* system call number */
+ int sys_panic;		/* flag to indicate system-wide panic */
+ 
+ extern int errno;	/* error number set by system library */
+ 
+ /* Declare some local functions. */
+ FORWARD _PROTOTYPE(void init_server, (int argc, char **argv)		);
+ FORWARD _PROTOTYPE(void exit_server, (void)				);
+ FORWARD _PROTOTYPE(void sig_handler, (void)				);
+ FORWARD _PROTOTYPE(void get_work, (message *m_ptr)			);
+ FORWARD _PROTOTYPE(void reply, (int whom, message *m_ptr)		);
+ 
+ /*===========================================================================*
+  *				main                                         *
+  *===========================================================================*/
+ PUBLIC int main(int argc, char **argv)
+ {
+ /* This is the main routine of this service. The main loop consists of 
+  * three major activities: getting new work, processing the work, and
+  * sending the reply. The loop never terminates, unless a panic occurs.
+  */
+   message m;
+   int result;                 
+   sigset_t sigset;
+ 
+   /* Initialize the server, then go to work. */
+   init_server(argc, argv);
+ 
+   /* Main loop - get work and do it, forever. */         
+   while (TRUE) {              
+ 
+       /* Wait for incoming message, sets 'callnr' and 'who'. */
+       get_work(&m);
+       switch (callnr) {
+       case PROC_EVENT:
+ 	  sig_handler();
+           continue;
+       case SS_SEMA_INIT:
+           result = do_sema_init(&m);
+           break;
+       case SS_SEMA_DOWN:
+           result = do_sema_down(&m);
+           break;
+       case SS_SEMA_UP:
+           result = do_sema_up(&m);
+           break;
+       case SS_SEMA_RELEASE:
+           result = do_sema_release(&m);
+           break;
+       default: 
+           report("SS","warning, got illegal request from:", m.m_source);
+           result = EINVAL;
+       }
+ 
+       /* Finally send reply message, unless disabled. */
+       if (result != EDONTREPLY) {
+           m.m_type = result;  		/* build reply message */
+ 	  reply(who_e, &m);		/* send it away */
+       }
+   }
+   return(OK);				/* shouldn't come here */
+ }
+ 
+ /*===========================================================================*
+  *				 init_server                                 *
+  *===========================================================================*/
+ PRIVATE void init_server(int argc, char **argv)
+ {
+ /* Initialize the data store server. */
+   int i, s;
+   struct sigaction sigact;
+   
+   /* Initialize all semaphores. */
+   init_all_semaphore();
+ 
+   /* Install signal handler. Ask PM to transform signal into message. */
+   sigact.sa_handler = SIG_MESS;
+   sigact.sa_mask = ~0;			/* block all other signals */
+   sigact.sa_flags = 0;			/* default behaviour */
+   if (sigaction(SIGTERM, &sigact, NULL) < 0) 
+       report("SS","warning, sigaction() failed", errno);
+ }
+ 
+ /*===========================================================================*
+  *				 sig_handler                                 *
+  *===========================================================================*/
+ PRIVATE void sig_handler()
+ {
+ /* Signal handler. */
+   sigset_t sigset;
+   int sig;
+ 
+   /* Try to obtain signal set from PM. */
+   if (getsigset(&sigset) != 0) return;
+ 
+   /* Check for known signals. */
+   if (sigismember(&sigset, SIGTERM)) {
+       exit_server();
+   }
+ }
+ 
+ /*===========================================================================*
+  *				exit_server                                  *
+  *===========================================================================*/
+ PRIVATE void exit_server()
+ {
+ /* Shut down the information service. */
+ 
+   /* Done. Now exit. */
+   exit(0);
+ }
+ 
+ /*===========================================================================*
+  *				get_work                                     *
+  *===========================================================================*/
+ PRIVATE void get_work(m_ptr)
+ message *m_ptr;				/* message buffer */
+ {
+     int status = 0;
+     status = receive(ANY, m_ptr);   /* this blocks until message arrives */
+     if (OK != status)
+         panic("SS","failed to receive message!", status);
+     who_e = m_ptr->m_source;        /* message arrived! set sender */
+     callnr = m_ptr->m_type;       /* set function call number */
+ }
+ 
+ /*===========================================================================*
+  *				reply					     *
+  *===========================================================================*/
+ PRIVATE void reply(who_e, m_ptr)
+ int who_e;                           	/* destination */
+ message *m_ptr;				/* message buffer */
+ {
+     int s;
+     s = send(who_e, m_ptr);    /* send the message */
+     if (OK != s)
+         panic("SS", "unable to send reply!", s);
+ }
+ 
diff -c -Nr src.clean/servers/ss/Makefile src/servers/ss/Makefile
*** src.clean/servers/ss/Makefile	1970-01-01 08:00:00.000000000 +0800
--- src/servers/ss/Makefile	2008-11-15 07:05:06.000000000 +0800
***************
*** 0 ****
--- 1,42 ----
+ # Makefile for Data Store Server (DS)
+ SERVER = ss
+ 
+ # directories
+ u = /usr
+ i = $u/include
+ s = $i/sys
+ m = $i/minix
+ b = $i/ibm
+ k = $u/src/kernel
+ p = $u/src/servers/pm
+ f = $u/src/servers/fs
+ 
+ # programs, flags, etc.
+ CC =	exec cc
+ CFLAGS = -I$i
+ LDFLAGS = -i
+ LIBS = -lsys -lsysutil 
+ 
+ OBJ = main.o semaphore.o 
+ 
+ # build local binary
+ all build:	$(SERVER)
+ $(SERVER):	$(OBJ)
+ 	$(CC) -o $@ $(LDFLAGS) $(OBJ) $(LIBS)
+ 	install -S 16k $@
+ 
+ # install with other servers
+ install: $(SERVER)
+ 	install -o root -c $? /sbin/$(SERVER)
+ #	install -o root -cs $? $@
+ 
+ # clean up local files
+ clean:
+ 	rm -f $(SERVER) *.o *.bak 
+ 
+ depend: 
+ 	/usr/bin/mkdep "$(CC) -E $(CPPFLAGS)" *.c > .depend
+ 
+ # Include generated dependencies.
+ include .depend
+ 
diff -c -Nr src.clean/servers/ss/proto.h src/servers/ss/proto.h
*** src.clean/servers/ss/proto.h	1970-01-01 08:00:00.000000000 +0800
--- src/servers/ss/proto.h	2008-11-16 02:05:44.000000000 +0800
***************
*** 0 ****
--- 1,11 ----
+ /* Function prototypes. */
+ 
+ /* main.c */
+ _PROTOTYPE(int main, (int argc, char **argv));
+ 
+ /* semaphore.c */
+ _PROTOTYPE(int init_all_semaphore, (void));
+ _PROTOTYPE(int do_sema_init, (message *m_ptr));
+ _PROTOTYPE(int do_sema_down, (message *m_ptr));
+ _PROTOTYPE(int do_sema_up, (message *m_ptr));
+ _PROTOTYPE(int do_sema_release, (message *m_ptr));
diff -c -Nr src.clean/servers/ss/semaphore.c src/servers/ss/semaphore.c
*** src.clean/servers/ss/semaphore.c	1970-01-01 08:00:00.000000000 +0800
--- src/servers/ss/semaphore.c	2008-11-17 07:54:22.000000000 +0800
***************
*** 0 ****
--- 1,100 ----
+ /* Implementation of the Semaphore Server. */
+ 
+ #include "inc.h"
+ 
+ PRIVATE Semaphore semaphores[MAX_SEMAPHORE];
+ 
+ PUBLIC int init_all_semaphore(void)
+ {
+   int i;
+   for (i=0;i<MAX_SEMAPHORE;i++){
+ 	  semaphores[i].actived=FALSE;
+ 	  semaphores[i].begin=0;
+ 	  semaphores[i].end=0;
+ 	  semaphores[i].queue_size=0;
+   }
+   return(OK);
+ }
+ 
+ PUBLIC int do_sema_init(m_ptr)
+ message *m_ptr;					/* request message */
+ {
+   int number;
+   int value;
+   number=m_ptr->SS_SEMAPHORE_NUMBER;
+   value=m_ptr->SS_START_VALUE;
+   if (semaphores[number].actived){
+     return(EINVAL);
+   }else{
+     semaphores[number].actived=TRUE;
+     semaphores[number].value=value;
+     semaphores[number].begin=0;
+     semaphores[number].end=0;
+     semaphores[number].queue_size=0;
+   }
+   return(OK);
+ }
+ 
+ 
+ PUBLIC int do_sema_down(m_ptr)
+ message *m_ptr;					/* request message */
+ {
+   int number;
+   Semaphore *s;
+   number=m_ptr->SS_SEMAPHORE_NUMBER;
+   s=&semaphores[number];
+   if (!s->actived){
+     return(EINVAL);
+   }
+   if (s->value > 0){
+     s->value--;
+     return(OK);
+   }else{
+     s->queue[s->end]=m_ptr->m_source;
+     s->end = (s->end+1) % MAX_QUEUE_SIZE;
+     s->queue_size++;
+   }
+   return(EDONTREPLY);	
+ }
+ 
+ 
+ PUBLIC int do_sema_up(m_ptr)
+ message *m_ptr;					/* request message */
+ {
+   message m;
+   int number;
+   Semaphore *s;
+   number=m_ptr->SS_SEMAPHORE_NUMBER;
+   s=&semaphores[number];
+   if (!s->actived){
+     return(EINVAL);
+   }
+   s->value++;
+   if (s->queue_size>0){
+     m.m_type=OK;
+     m.m_source=s->queue[s->begin];
+     s->begin = (s->begin+1) % MAX_QUEUE_SIZE;
+     s->value--;
+     s->queue_size--;
+     send(m.m_source,&m);
+   }
+   return(OK);
+ }
+ 
+ PUBLIC int do_sema_release(m_ptr)
+ message *m_ptr;					/* request message */
+ {
+   int number;
+   Semaphore *s;
+   number=m_ptr->SS_SEMAPHORE_NUMBER;
+   s=&semaphores[number];
+   if (!s->actived){
+     return(EINVAL);
+   }
+   s->queue_size=0;
+   s->begin=0;
+   s->end=0;
+   s->actived=FALSE;
+   return(OK);
+ }
+ 
diff -c -Nr src.clean/servers/ss/semaphore.h src/servers/ss/semaphore.h
*** src.clean/servers/ss/semaphore.h	1970-01-01 08:00:00.000000000 +0800
--- src/servers/ss/semaphore.h	2008-11-16 00:50:29.000000000 +0800
***************
*** 0 ****
--- 1,12 ----
+ #define MAX_QUEUE_SIZE  100
+ #define MAX_SEMAPHORE 10
+ 
+ typedef struct{
+   int value;
+   int actived;
+   int queue[MAX_QUEUE_SIZE];
+   int begin;
+   int end;
+   int queue_size;
+ } Semaphore;
+ 
diff -c -Nr src.clean/tools/Makefile src/tools/Makefile
*** src.clean/tools/Makefile	2008-11-15 06:52:23.000000000 +0800
--- src/tools/Makefile	2008-11-15 07:33:40.000000000 +0800
***************
*** 10,15 ****
--- 10,16 ----
  	../servers/pm/pm \
  	../servers/fs/fs \
  	../servers/rs/rs \
+ 	../servers/ss/ss \
  	../servers/ds/ds \
  	../drivers/tty/tty \
  	../drivers/memory/memory \