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/* Jim - A small embeddable Tcl interpreter
*
* Copyright 2005 Salvatore Sanfilippo <antirez@invece.org>
* Copyright 2005 Clemens Hintze <c.hintze@gmx.net>
* Copyright 2005 patthoyts - Pat Thoyts <patthoyts@users.sf.net>
* Copyright 2008 oharboe - Øyvind Harboe - oyvind.harboe@zylin.com
* Copyright 2008 Andrew Lunn <andrew@lunn.ch>
* Copyright 2008 Duane Ellis <openocd@duaneellis.com>
* Copyright 2008 Uwe Klein <uklein@klein-messgeraete.de>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE JIM TCL PROJECT ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
* PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* JIM TCL PROJECT OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* The views and conclusions contained in the software and documentation
* are those of the authors and should not be interpreted as representing
* official policies, either expressed or implied, of the Jim Tcl Project.
**/
#include "jimautoconf.h"
#include <jim.h>
#include <jim-eventloop.h>
#include <time.h>
#include <string.h>
#include <errno.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_SYS_TIME_H
#include <sys/time.h>
#endif
#if defined(__MINGW32__)
#include <windows.h>
#include <winsock.h>
#define msleep Sleep
#else
#include <sys/types.h>
#ifdef HAVE_SYS_SELECT_H
#include <sys/select.h>
#endif
#ifndef HAVE_USLEEP
/* XXX: Implement this in terms of select() or nanosleep() */
#define msleep(MS) sleep((MS) / 1000)
#warning "sub-second sleep not supported"
#else
#define msleep(MS) sleep((MS) / 1000); usleep(((MS) % 1000) * 1000);
#endif
#endif
/* --- */
/* File event structure */
typedef struct Jim_FileEvent
{
int fd;
int mask; /* one of JIM_EVENT_(READABLE|WRITABLE|EXCEPTION) */
Jim_FileProc *fileProc;
Jim_EventFinalizerProc *finalizerProc;
void *clientData;
struct Jim_FileEvent *next;
} Jim_FileEvent;
/* Time event structure */
typedef struct Jim_TimeEvent
{
jim_wide id; /* time event identifier. */
long initialms; /* initial relative timer value */
jim_wide when; /* milliseconds */
Jim_TimeProc *timeProc;
Jim_EventFinalizerProc *finalizerProc;
void *clientData;
struct Jim_TimeEvent *next;
} Jim_TimeEvent;
/* Per-interp stucture containing the state of the event loop */
typedef struct Jim_EventLoop
{
Jim_FileEvent *fileEventHead;
Jim_TimeEvent *timeEventHead;
jim_wide timeEventNextId; /* highest event id created, starting at 1 */
time_t timeBase;
int suppress_bgerror; /* bgerror returned break, so don't call it again */
} Jim_EventLoop;
static void JimAfterTimeHandler(Jim_Interp *interp, void *clientData);
static void JimAfterTimeEventFinalizer(Jim_Interp *interp, void *clientData);
int Jim_EvalObjBackground(Jim_Interp *interp, Jim_Obj *scriptObjPtr)
{
Jim_EventLoop *eventLoop = Jim_GetAssocData(interp, "eventloop");
Jim_CallFrame *savedFramePtr;
int retval;
savedFramePtr = interp->framePtr;
interp->framePtr = interp->topFramePtr;
retval = Jim_EvalObj(interp, scriptObjPtr);
interp->framePtr = savedFramePtr;
/* Try to report the error (if any) via the bgerror proc */
if (retval != JIM_OK && !eventLoop->suppress_bgerror) {
Jim_Obj *objv[2];
int rc = JIM_ERR;
objv[0] = Jim_NewStringObj(interp, "bgerror", -1);
objv[1] = Jim_GetResult(interp);
Jim_IncrRefCount(objv[0]);
Jim_IncrRefCount(objv[1]);
if (Jim_GetCommand(interp, objv[0], JIM_NONE) == NULL || (rc = Jim_EvalObjVector(interp, 2, objv)) != JIM_OK) {
if (rc == JIM_BREAK) {
/* No more bgerror calls */
eventLoop->suppress_bgerror++;
}
else {
/* Report the error to stderr. */
Jim_MakeErrorMessage(interp);
fprintf(stderr, "%s\n", Jim_String(Jim_GetResult(interp)));
/* And reset the result */
Jim_SetResultString(interp, "", -1);
}
}
Jim_DecrRefCount(interp, objv[0]);
Jim_DecrRefCount(interp, objv[1]);
}
return retval;
}
void Jim_CreateFileHandler(Jim_Interp *interp, int fd, int mask,
Jim_FileProc * proc, void *clientData, Jim_EventFinalizerProc * finalizerProc)
{
Jim_FileEvent *fe;
Jim_EventLoop *eventLoop = Jim_GetAssocData(interp, "eventloop");
fe = Jim_Alloc(sizeof(*fe));
fe->fd = fd;
fe->mask = mask;
fe->fileProc = proc;
fe->finalizerProc = finalizerProc;
fe->clientData = clientData;
fe->next = eventLoop->fileEventHead;
eventLoop->fileEventHead = fe;
}
/**
* Removes all event handlers for 'handle' that match 'mask'.
*/
void Jim_DeleteFileHandler(Jim_Interp *interp, int fd, int mask)
{
Jim_FileEvent *fe, *next, *prev = NULL;
Jim_EventLoop *eventLoop = Jim_GetAssocData(interp, "eventloop");
for (fe = eventLoop->fileEventHead; fe; fe = next) {
next = fe->next;
if (fe->fd == fd && (fe->mask & mask)) {
/* Remove this entry from the list */
if (prev == NULL)
eventLoop->fileEventHead = next;
else
prev->next = next;
if (fe->finalizerProc)
fe->finalizerProc(interp, fe->clientData);
Jim_Free(fe);
continue;
}
prev = fe;
}
}
/**
* Returns the time since interp creation in milliseconds.
*/
static jim_wide JimGetTime(Jim_EventLoop *eventLoop)
{
struct timeval tv;
gettimeofday(&tv, NULL);
return (jim_wide)(tv.tv_sec - eventLoop->timeBase) * 1000 + tv.tv_usec / 1000;
}
jim_wide Jim_CreateTimeHandler(Jim_Interp *interp, jim_wide milliseconds,
Jim_TimeProc * proc, void *clientData, Jim_EventFinalizerProc * finalizerProc)
{
Jim_EventLoop *eventLoop = Jim_GetAssocData(interp, "eventloop");
jim_wide id = ++eventLoop->timeEventNextId;
Jim_TimeEvent *te, *e, *prev;
te = Jim_Alloc(sizeof(*te));
te->id = id;
te->initialms = milliseconds;
te->when = JimGetTime(eventLoop) + milliseconds;
te->timeProc = proc;
te->finalizerProc = finalizerProc;
te->clientData = clientData;
/* Add to the appropriate place in the list */
prev = NULL;
for (e = eventLoop->timeEventHead; e; e = e->next) {
if (te->when < e->when) {
break;
}
prev = e;
}
if (prev) {
te->next = prev->next;
prev->next = te;
}
else {
te->next = eventLoop->timeEventHead;
eventLoop->timeEventHead = te;
}
return id;
}
static jim_wide JimParseAfterId(Jim_Obj *idObj)
{
const char *tok = Jim_String(idObj);
jim_wide id;
if (strncmp(tok, "after#", 6) == 0 && Jim_StringToWide(tok + 6, &id, 10) == JIM_OK) {
/* Got an event by id */
return id;
}
return -1;
}
static jim_wide JimFindAfterByScript(Jim_EventLoop *eventLoop, Jim_Obj *scriptObj)
{
Jim_TimeEvent *te;
for (te = eventLoop->timeEventHead; te; te = te->next) {
/* Is this an 'after' event? */
if (te->timeProc == JimAfterTimeHandler) {
if (Jim_StringEqObj(scriptObj, te->clientData)) {
return te->id;
}
}
}
return -1; /* NO event with the specified ID found */
}
static Jim_TimeEvent *JimFindTimeHandlerById(Jim_EventLoop *eventLoop, jim_wide id)
{
Jim_TimeEvent *te;
for (te = eventLoop->timeEventHead; te; te = te->next) {
if (te->id == id) {
return te;
}
}
return NULL;
}
static Jim_TimeEvent *Jim_RemoveTimeHandler(Jim_EventLoop *eventLoop, jim_wide id)
{
Jim_TimeEvent *te, *prev = NULL;
for (te = eventLoop->timeEventHead; te; te = te->next) {
if (te->id == id) {
if (prev == NULL)
eventLoop->timeEventHead = te->next;
else
prev->next = te->next;
return te;
}
prev = te;
}
return NULL;
}
static void Jim_FreeTimeHandler(Jim_Interp *interp, Jim_TimeEvent *te)
{
if (te->finalizerProc)
te->finalizerProc(interp, te->clientData);
Jim_Free(te);
}
jim_wide Jim_DeleteTimeHandler(Jim_Interp *interp, jim_wide id)
{
Jim_TimeEvent *te;
Jim_EventLoop *eventLoop = Jim_GetAssocData(interp, "eventloop");
if (id > eventLoop->timeEventNextId) {
return -2; /* wrong event ID */
}
te = Jim_RemoveTimeHandler(eventLoop, id);
if (te) {
jim_wide remain;
remain = te->when - JimGetTime(eventLoop);
remain = (remain < 0) ? 0 : remain;
Jim_FreeTimeHandler(interp, te);
return remain;
}
return -1; /* NO event with the specified ID found */
}
/* --- POSIX version of Jim_ProcessEvents, for now the only available --- */
/* Process every pending time event, then every pending file event
* (that may be registered by time event callbacks just processed).
* The behaviour depends upon the setting of flags:
*
* If flags is 0, the function does nothing and returns.
* if flags has JIM_ALL_EVENTS set, all event types are processed.
* if flags has JIM_FILE_EVENTS set, file events are processed.
* if flags has JIM_TIME_EVENTS set, time events are processed.
* if flags has JIM_DONT_WAIT set, the function returns as soon as all
* the events that are possible to process without waiting are processed.
*
* Returns the number of events processed or -1 if
* there are no matching handlers, or -2 on error.
*/
int Jim_ProcessEvents(Jim_Interp *interp, int flags)
{
jim_wide sleep_ms = -1;
int processed = 0;
Jim_EventLoop *eventLoop = Jim_GetAssocData(interp, "eventloop");
Jim_FileEvent *fe = eventLoop->fileEventHead;
Jim_TimeEvent *te;
jim_wide maxId;
if ((flags & JIM_FILE_EVENTS) == 0 || fe == NULL) {
/* No file events */
if ((flags & JIM_TIME_EVENTS) == 0 || eventLoop->timeEventHead == NULL) {
/* No time events */
return -1;
}
}
/* Note that we want call select() even if there are no
* file events to process as long as we want to process time
* events, in order to sleep until the next time event is ready
* to fire. */
if (flags & JIM_DONT_WAIT) {
/* Wait no time */
sleep_ms = 0;
}
else if (flags & JIM_TIME_EVENTS) {
/* The nearest timer is always at the head of the list */
if (eventLoop->timeEventHead) {
Jim_TimeEvent *shortest = eventLoop->timeEventHead;
/* Calculate the time missing for the nearest
* timer to fire. */
sleep_ms = shortest->when - JimGetTime(eventLoop);
if (sleep_ms < 0) {
sleep_ms = 0;
}
}
else {
/* Wait forever */
sleep_ms = -1;
}
}
#ifdef HAVE_SELECT
if (flags & JIM_FILE_EVENTS) {
int retval;
struct timeval tv, *tvp = NULL;
fd_set rfds, wfds, efds;
int maxfd = -1;
FD_ZERO(&rfds);
FD_ZERO(&wfds);
FD_ZERO(&efds);
/* Check file events */
while (fe != NULL) {
if (fe->mask & JIM_EVENT_READABLE)
FD_SET(fe->fd, &rfds);
if (fe->mask & JIM_EVENT_WRITABLE)
FD_SET(fe->fd, &wfds);
if (fe->mask & JIM_EVENT_EXCEPTION)
FD_SET(fe->fd, &efds);
if (maxfd < fe->fd)
maxfd = fe->fd;
fe = fe->next;
}
if (sleep_ms >= 0) {
tvp = &tv;
tvp->tv_sec = sleep_ms / 1000;
tvp->tv_usec = 1000 * (sleep_ms % 1000);
}
retval = select(maxfd + 1, &rfds, &wfds, &efds, tvp);
if (retval < 0) {
if (errno == EINVAL) {
/* This can happen on mingw32 if a non-socket filehandle is passed */
Jim_SetResultString(interp, "non-waitable filehandle", -1);
return -2;
}
}
else if (retval > 0) {
fe = eventLoop->fileEventHead;
while (fe != NULL) {
int mask = 0;
int fd = fe->fd;
if ((fe->mask & JIM_EVENT_READABLE) && FD_ISSET(fd, &rfds))
mask |= JIM_EVENT_READABLE;
if (fe->mask & JIM_EVENT_WRITABLE && FD_ISSET(fd, &wfds))
mask |= JIM_EVENT_WRITABLE;
if (fe->mask & JIM_EVENT_EXCEPTION && FD_ISSET(fd, &efds))
mask |= JIM_EVENT_EXCEPTION;
if (mask) {
if (fe->fileProc(interp, fe->clientData, mask) != JIM_OK) {
/* Remove the element on handler error */
Jim_DeleteFileHandler(interp, fd, mask);
/* At this point fe is no longer valid - it will be assigned below */
}
processed++;
/* After an event is processed our file event list
* may no longer be the same, so what we do
* is to clear the bit for this file descriptor and
* restart again from the head. */
FD_CLR(fd, &rfds);
FD_CLR(fd, &wfds);
FD_CLR(fd, &efds);
fe = eventLoop->fileEventHead;
}
else {
fe = fe->next;
}
}
}
}
#else
if (sleep_ms > 0) {
msleep(sleep_ms);
}
#endif
/* Check time events */
te = eventLoop->timeEventHead;
maxId = eventLoop->timeEventNextId;
while (te) {
jim_wide id;
if (te->id > maxId) {
te = te->next;
continue;
}
if (JimGetTime(eventLoop) >= te->when) {
id = te->id;
/* Remove from the list before executing */
Jim_RemoveTimeHandler(eventLoop, id);
te->timeProc(interp, te->clientData);
/* After an event is processed our time event list may
* no longer be the same, so we restart from head.
* Still we make sure to don't process events registered
* by event handlers itself in order to don't loop forever
* even in case an [after 0] that continuously register
* itself. To do so we saved the max ID we want to handle. */
Jim_FreeTimeHandler(interp, te);
te = eventLoop->timeEventHead;
processed++;
}
else {
te = te->next;
}
}
return processed;
}
/* ---------------------------------------------------------------------- */
static void JimELAssocDataDeleProc(Jim_Interp *interp, void *data)
{
void *next;
Jim_FileEvent *fe;
Jim_TimeEvent *te;
Jim_EventLoop *eventLoop = data;
fe = eventLoop->fileEventHead;
while (fe) {
next = fe->next;
if (fe->finalizerProc)
fe->finalizerProc(interp, fe->clientData);
Jim_Free(fe);
fe = next;
}
te = eventLoop->timeEventHead;
while (te) {
next = te->next;
if (te->finalizerProc)
te->finalizerProc(interp, te->clientData);
Jim_Free(te);
te = next;
}
Jim_Free(data);
}
static int JimELVwaitCommand(Jim_Interp *interp, int argc, Jim_Obj *const *argv)
{
Jim_EventLoop *eventLoop = Jim_CmdPrivData(interp);
Jim_Obj *oldValue;
int rc;
if (argc != 2) {
Jim_WrongNumArgs(interp, 1, argv, "name");
return JIM_ERR;
}
oldValue = Jim_GetGlobalVariable(interp, argv[1], JIM_NONE);
if (oldValue) {
Jim_IncrRefCount(oldValue);
}
else {
/* If a result was left, it is an error */
if (Jim_Length(Jim_GetResult(interp))) {
return JIM_ERR;
}
}
eventLoop->suppress_bgerror = 0;
while ((rc = Jim_ProcessEvents(interp, JIM_ALL_EVENTS)) >= 0) {
Jim_Obj *currValue;
currValue = Jim_GetGlobalVariable(interp, argv[1], JIM_NONE);
/* Stop the loop if the vwait-ed variable changed value,
* or if was unset and now is set (or the contrary)
* or if a signal was caught
*/
if ((oldValue && !currValue) ||
(!oldValue && currValue) ||
(oldValue && currValue && !Jim_StringEqObj(oldValue, currValue)) ||
Jim_CheckSignal(interp)) {
break;
}
}
if (oldValue)
Jim_DecrRefCount(interp, oldValue);
if (rc == -2) {
return JIM_ERR;
}
Jim_SetEmptyResult(interp);
return JIM_OK;
}
static int JimELUpdateCommand(Jim_Interp *interp, int argc, Jim_Obj *const *argv)
{
Jim_EventLoop *eventLoop = Jim_CmdPrivData(interp);
static const char * const options[] = {
"idletasks", NULL
};
enum { UPDATE_IDLE, UPDATE_NONE };
int option = UPDATE_NONE;
int flags = JIM_TIME_EVENTS;
if (argc == 1) {
flags = JIM_ALL_EVENTS;
}
else if (argc > 2 || Jim_GetEnum(interp, argv[1], options, &option, NULL, JIM_ERRMSG | JIM_ENUM_ABBREV) != JIM_OK) {
Jim_WrongNumArgs(interp, 1, argv, "?idletasks?");
return JIM_ERR;
}
eventLoop->suppress_bgerror = 0;
while (Jim_ProcessEvents(interp, flags | JIM_DONT_WAIT) > 0) {
}
return JIM_OK;
}
static void JimAfterTimeHandler(Jim_Interp *interp, void *clientData)
{
Jim_Obj *objPtr = clientData;
Jim_EvalObjBackground(interp, objPtr);
}
static void JimAfterTimeEventFinalizer(Jim_Interp *interp, void *clientData)
{
Jim_Obj *objPtr = clientData;
Jim_DecrRefCount(interp, objPtr);
}
static int JimELAfterCommand(Jim_Interp *interp, int argc, Jim_Obj *const *argv)
{
Jim_EventLoop *eventLoop = Jim_CmdPrivData(interp);
jim_wide ms = 0, id;
Jim_Obj *objPtr, *idObjPtr;
static const char * const options[] = {
"cancel", "info", "idle", NULL
};
enum
{ AFTER_CANCEL, AFTER_INFO, AFTER_IDLE, AFTER_RESTART, AFTER_EXPIRE, AFTER_CREATE };
int option = AFTER_CREATE;
if (argc < 2) {
Jim_WrongNumArgs(interp, 1, argv, "option ?arg ...?");
return JIM_ERR;
}
if (Jim_GetWide(interp, argv[1], &ms) != JIM_OK) {
if (Jim_GetEnum(interp, argv[1], options, &option, "argument", JIM_ERRMSG) != JIM_OK) {
return JIM_ERR;
}
Jim_SetEmptyResult(interp);
}
else if (argc == 2) {
/* Simply a sleep */
msleep(ms);
return JIM_OK;
}
switch (option) {
case AFTER_IDLE:
if (argc < 3) {
Jim_WrongNumArgs(interp, 2, argv, "script ?script ...?");
return JIM_ERR;
}
/* fall through */
case AFTER_CREATE: {
Jim_Obj *scriptObj = Jim_ConcatObj(interp, argc - 2, argv + 2);
Jim_IncrRefCount(scriptObj);
id = Jim_CreateTimeHandler(interp, ms, JimAfterTimeHandler, scriptObj,
JimAfterTimeEventFinalizer);
objPtr = Jim_NewStringObj(interp, NULL, 0);
Jim_AppendString(interp, objPtr, "after#", -1);
idObjPtr = Jim_NewIntObj(interp, id);
Jim_IncrRefCount(idObjPtr);
Jim_AppendObj(interp, objPtr, idObjPtr);
Jim_DecrRefCount(interp, idObjPtr);
Jim_SetResult(interp, objPtr);
return JIM_OK;
}
case AFTER_CANCEL:
if (argc < 3) {
Jim_WrongNumArgs(interp, 2, argv, "id|command");
return JIM_ERR;
}
else {
jim_wide remain = 0;
id = JimParseAfterId(argv[2]);
if (id <= 0) {
/* Not an event id, so search by script */
Jim_Obj *scriptObj = Jim_ConcatObj(interp, argc - 2, argv + 2);
id = JimFindAfterByScript(eventLoop, scriptObj);
Jim_FreeNewObj(interp, scriptObj);
if (id <= 0) {
/* Not found */
break;
}
}
remain = Jim_DeleteTimeHandler(interp, id);
if (remain >= 0) {
Jim_SetResultInt(interp, remain);
}
}
break;
case AFTER_INFO:
if (argc == 2) {
Jim_TimeEvent *te = eventLoop->timeEventHead;
Jim_Obj *listObj = Jim_NewListObj(interp, NULL, 0);
char buf[30];
const char *fmt = "after#%" JIM_WIDE_MODIFIER;
while (te) {
snprintf(buf, sizeof(buf), fmt, te->id);
Jim_ListAppendElement(interp, listObj, Jim_NewStringObj(interp, buf, -1));
te = te->next;
}
Jim_SetResult(interp, listObj);
}
else if (argc == 3) {
id = JimParseAfterId(argv[2]);
if (id >= 0) {
Jim_TimeEvent *e = JimFindTimeHandlerById(eventLoop, id);
if (e && e->timeProc == JimAfterTimeHandler) {
Jim_Obj *listObj = Jim_NewListObj(interp, NULL, 0);
Jim_ListAppendElement(interp, listObj, e->clientData);
Jim_ListAppendElement(interp, listObj, Jim_NewStringObj(interp, e->initialms ? "timer" : "idle", -1));
Jim_SetResult(interp, listObj);
return JIM_OK;
}
}
Jim_SetResultFormatted(interp, "event \"%#s\" doesn't exist", argv[2]);
return JIM_ERR;
}
else {
Jim_WrongNumArgs(interp, 2, argv, "?id?");
return JIM_ERR;
}
break;
}
return JIM_OK;
}
int Jim_eventloopInit(Jim_Interp *interp)
{
Jim_EventLoop *eventLoop;
if (Jim_PackageProvide(interp, "eventloop", "1.0", JIM_ERRMSG))
return JIM_ERR;
eventLoop = Jim_Alloc(sizeof(*eventLoop));
memset(eventLoop, 0, sizeof(*eventLoop));
Jim_SetAssocData(interp, "eventloop", JimELAssocDataDeleProc, eventLoop);
Jim_CreateCommand(interp, "vwait", JimELVwaitCommand, eventLoop, NULL);
Jim_CreateCommand(interp, "update", JimELUpdateCommand, eventLoop, NULL);
Jim_CreateCommand(interp, "after", JimELAfterCommand, eventLoop, NULL);
return JIM_OK;
}