ref: 83f8d591689cae964ba58fbcf172f6a4fa7003ed
dir: /sys/src/libdraw/event.c/
#include <u.h>
#include <libc.h>
#include <draw.h>
#include <cursor.h>
#include <event.h>
typedef struct Slave Slave;
typedef struct Ebuf Ebuf;
struct Slave
{
int pid;
Ebuf *head; /* queue of messages for this descriptor */
Ebuf *tail;
int (*fn)(int, Event*, uchar*, int);
};
struct Ebuf
{
Ebuf *next;
int n; /* number of bytes in buf */
uchar buf[EMAXMSG];
};
static Slave eslave[MAXSLAVE];
static int Skeyboard = -1;
static int Smouse = -1;
static int Stimer = -1;
static int logfid;
static int nslave;
static int parentpid;
static int epipe[2];
static int eforkslave(ulong);
static void extract(void);
static void ekill(void);
static int enote(void *, char *);
static int mousefd;
static int cursorfd;
static
Ebuf*
ebread(Slave *s)
{
Ebuf *eb;
while((eb = s->head) == 0)
extract();
s->head = eb->next;
if(s->head == 0)
s->tail = 0;
return eb;
}
ulong
event(Event *e)
{
return eread(~0UL, e);
}
ulong
eread(ulong keys, Event *e)
{
Ebuf *eb;
int i, id;
if(keys == 0)
return 0;
for(;;){
for(i=0; i<nslave; i++)
if((keys & (1<<i)) && eslave[i].head){
id = 1<<i;
if(i == Smouse)
e->mouse = emouse();
else if(i == Skeyboard)
e->kbdc = ekbd();
else if(i == Stimer)
eslave[i].head = 0;
else{
eb = ebread(&eslave[i]);
e->n = eb->n;
if(eslave[i].fn)
id = (*eslave[i].fn)(id, e, eb->buf, eb->n);
else
memmove(e->data, eb->buf, eb->n);
free(eb);
}
return id;
}
extract();
}
}
int
ecanmouse(void)
{
if(Smouse < 0)
drawerror(display, "events: mouse not initialized");
return ecanread(Emouse);
}
int
ecankbd(void)
{
if(Skeyboard < 0)
drawerror(display, "events: keyboard not initialzed");
return ecanread(Ekeyboard);
}
int
ecanread(ulong keys)
{
Dir *d;
int i;
ulong l;
for(;;){
for(i=0; i<nslave; i++)
if((keys & (1<<i)) && eslave[i].head)
return 1;
d = dirfstat(epipe[0]);
if(d == nil)
drawerror(display, "events: ecanread stat error");
l = d->length;
free(d);
if(l == 0)
return 0;
extract();
}
}
ulong
estartfn(ulong key, int fd, int n, int (*fn)(int, Event*, uchar*, int))
{
char buf[EMAXMSG+1];
int i, r;
if(fd < 0)
drawerror(display, "events: bad file descriptor");
if(n <= 0 || n > EMAXMSG)
n = EMAXMSG;
i = eforkslave(key);
if(i < MAXSLAVE){
eslave[i].fn = fn;
return 1<<i;
}
buf[0] = i - MAXSLAVE;
while((r = read(fd, buf+1, n))>0)
if(write(epipe[1], buf, r+1)!=r+1)
break;
buf[0] = MAXSLAVE;
write(epipe[1], buf, 1);
_exits(0);
return 0;
}
ulong
estart(ulong key, int fd, int n)
{
return estartfn(key, fd, n, nil);
}
ulong
etimer(ulong key, int n)
{
char t[2];
if(Stimer != -1)
drawerror(display, "events: timer started twice");
Stimer = eforkslave(key);
if(Stimer < MAXSLAVE)
return 1<<Stimer;
if(n <= 0)
n = 1000;
t[0] = t[1] = Stimer - MAXSLAVE;
do
sleep(n);
while(write(epipe[1], t, 2) == 2);
t[0] = MAXSLAVE;
write(epipe[1], t, 1);
_exits(0);
return 0;
}
static void
ekeyslave(int fd)
{
Rune r;
char t[1+UTFmax], k[10];
int kr, kn, w;
if(eforkslave(Ekeyboard) < MAXSLAVE)
return;
kn = 0;
t[0] = Skeyboard;
for(;;){
while(!fullrune(k, kn)){
kr = read(fd, k+kn, sizeof k - kn);
if(kr <= 0)
goto breakout;
kn += kr;
}
w = chartorune(&r, k);
kn -= w;
memmove(t+1, k, w);
memmove(k, &k[w], kn);
if(write(epipe[1], t, sizeof(t)) != sizeof(t))
break;
}
breakout:;
t[0] = MAXSLAVE;
write(epipe[1], t, 1);
_exits(0);
}
void
einit(ulong keys)
{
int ctl, fd;
char buf[256];
parentpid = getpid();
if(pipe(epipe) < 0)
drawerror(display, "events: einit pipe");
atexit(ekill);
atnotify(enote, 1);
snprint(buf, sizeof buf, "%s/mouse", display->devdir);
mousefd = open(buf, ORDWR|OCEXEC);
if(mousefd < 0)
drawerror(display, "einit: can't open mouse\n");
snprint(buf, sizeof buf, "%s/cursor", display->devdir);
cursorfd = open(buf, ORDWR|OCEXEC);
if(cursorfd < 0)
drawerror(display, "einit: can't open cursor\n");
if(keys&Ekeyboard){
snprint(buf, sizeof buf, "%s/cons", display->devdir);
fd = open(buf, OREAD);
if(fd < 0)
drawerror(display, "events: can't open console");
snprint(buf, sizeof buf, "%s/consctl", display->devdir);
ctl = open("/dev/consctl", OWRITE|OCEXEC);
if(ctl < 0)
drawerror(display, "events: can't open consctl");
write(ctl, "rawon", 5);
for(Skeyboard=0; Ekeyboard & ~(1<<Skeyboard); Skeyboard++)
;
ekeyslave(fd);
}
if(keys&Emouse){
estart(Emouse, mousefd, 1+4*12);
for(Smouse=0; Emouse & ~(1<<Smouse); Smouse++)
;
}
}
static void
extract(void)
{
Slave *s;
Ebuf *eb;
int i, n;
uchar ebuf[EMAXMSG+1];
/* avoid generating a message if there's nothing to show. */
/* this test isn't perfect, though; could do flushimage(display, 0) then call extract */
/* also: make sure we don't interfere if we're multiprocessing the display */
if(display->locking){
/* if locking is being done by program, this means it can't depend on automatic flush in emouse() etc. */
if(canqlock(&display->qlock)){
if(display->bufp > display->buf)
flushimage(display, 1);
unlockdisplay(display);
}
}else
if(display->bufp > display->buf)
flushimage(display, 1);
loop:
if((n=read(epipe[0], ebuf, EMAXMSG+1)) < 0
|| ebuf[0] >= MAXSLAVE)
drawerror(display, "eof on event pipe");
if(n == 0)
goto loop;
i = ebuf[0];
if(i >= nslave || n <= 1)
drawerror(display, "events: protocol error: short read");
s = &eslave[i];
if(i == Stimer){
s->head = (Ebuf *)1;
return;
}
if(i == Skeyboard && n != (1+UTFmax))
drawerror(display, "events: protocol error: keyboard");
if(i == Smouse){
if(n < 1+1+2*12)
drawerror(display, "events: protocol error: mouse");
if(ebuf[1] == 'r')
eresized(1);
/* squash extraneous mouse events */
if((eb=s->tail) && memcmp(eb->buf+1+2*12, ebuf+1+1+2*12, 12)==0){
memmove(eb->buf, &ebuf[1], n - 1);
return;
}
}
/* try to save space by only allocating as much buffer as we need */
eb = malloc(sizeof(*eb) - sizeof(eb->buf) + n - 1);
if(eb == 0)
drawerror(display, "events: protocol error 4");
eb->n = n - 1;
memmove(eb->buf, &ebuf[1], n - 1);
eb->next = 0;
if(s->head)
s->tail->next = eb;
else
s->head = eb;
s->tail = eb;
}
static int
eforkslave(ulong key)
{
int i, pid;
for(i=0; i<MAXSLAVE; i++)
if((key & ~(1<<i)) == 0 && eslave[i].pid == 0){
if(nslave <= i)
nslave = i + 1;
/*
* share the file descriptors so the last child
* out closes all connections to the window server.
*/
switch(pid = rfork(RFPROC)){
case 0:
return MAXSLAVE+i;
case -1:
fprint(2, "events: fork error\n");
exits("fork");
}
eslave[i].pid = pid;
eslave[i].head = eslave[i].tail = 0;
return i;
}
drawerror(display, "events: bad slave assignment");
return 0;
}
static int
enote(void*, char *s)
{
int i, pid;
if(strncmp(s, "sys:", 4) == 0 || strcmp(s, "alarm") == 0)
return 0;
pid = getpid();
for(i=0; i<nslave; i++)
if(pid == eslave[i].pid)
return 1;
if(pid != parentpid)
return 0;
exits("killed");
return 1;
}
static void
ekill(void)
{
int i, pid;
pid = getpid();
for(i=0; i<nslave; i++){
if(eslave[i].pid == 0 || pid == eslave[i].pid)
continue; /* don't kill myself */
postnote(PNPROC, eslave[i].pid, "die");
}
}
Mouse
emouse(void)
{
Mouse m;
Ebuf *eb;
static but[2];
int b;
if(Smouse < 0)
drawerror(display, "events: mouse not initialized");
for(;;){
eb = ebread(&eslave[Smouse]);
if(!ecanmouse())
break;
free(eb); /* drop queued mouse events */
}
m.xy.x = atoi((char*)eb->buf+1+0*12);
m.xy.y = atoi((char*)eb->buf+1+1*12);
b = atoi((char*)eb->buf+1+2*12);
m.buttons = b;
m.msec = atoi((char*)eb->buf+1+3*12);
if (logfid)
fprint(logfid, "b: %d xy: %P\n", m.buttons, m.xy);
free(eb);
return m;
}
int
ekbd(void)
{
Ebuf *eb;
Rune r;
if(Skeyboard < 0)
drawerror(display, "events: keyboard not initialzed");
eb = ebread(&eslave[Skeyboard]);
chartorune(&r, (char*)eb->buf);
free(eb);
return r;
}
void
emoveto(Point pt)
{
char buf[2*12+2];
int n;
n = sprint(buf, "m%d %d", pt.x, pt.y);
write(mousefd, buf, n);
}
void
esetcursor(Cursor *c)
{
uchar curs[2*4+2*2*16];
if(c == 0)
write(cursorfd, curs, 0);
else{
BPLONG(curs+0*4, c->offset.x);
BPLONG(curs+1*4, c->offset.y);
memmove(curs+2*4, c->clr, 2*2*16);
write(cursorfd, curs, sizeof curs);
}
}
int
ereadmouse(Mouse *m)
{
int n;
char buf[128];
do{
n = read(mousefd, buf, sizeof(buf));
if(n < 0) /* probably interrupted */
return -1;
n = eatomouse(m, buf, n);
}while(n == 0);
return n;
}
int
eatomouse(Mouse *m, char *buf, int n)
{
if(n != 1+4*12){
werrstr("eatomouse: bad count");
return -1;
}
if(buf[0] == 'r')
eresized(1);
m->xy.x = atoi(buf+1+0*12);
m->xy.y = atoi(buf+1+1*12);
m->buttons = atoi(buf+1+2*12);
m->msec = atoi(buf+1+3*12);
return n;
}