mal_session.c

一个内存数据库的源代码这是服务器端还有客户端

#line 54 "/export/scratch0/monet/monet.GNU.64.64.d.14791/MonetDB5/src/mal/mal_session.mx"
#include "mal_config.h"
#include "mal_session.h"
#include "mal_instruction.h"	/* for pushEndInstruction() */
#include "mal_interpreter.h"	/* for showErrors(), runMAL(), garbageElement(), garbageCollector() */
#include "mal_linker.h"		/* for initLibraries() */
#include "mal_parser.h"		/* for parseMAL() */
#include "mal_namespace.h"
#include "mal_readline.h"
#include "mal_authorize.h"
#include <gdk.h>	/* for opendir and friends */

int
malBootstrap()
{
	Client c;
	str bootfile = "mal_init", bf;

	c = MCinitClient((oid)0, 0, 0);
	c->nspace = newModule(NULL, putName("user", 4));
	initLibraries();
	if (defaultScenario(c)) {
		GDKfatal("Failed to initialise default scenario");
		return 0;
	}
	bf = GDKgetenv("mal_bootstrap");
	if (bf)
		bootfile = bf;
	MSinitClientPrg(c,"user", "main");
	malInclude(c, bootfile, 0);
	mal_scope = c->nspace;
	pushEndInstruction(c->curprg->def);
	trimMalBlk(c->curprg->def);
	chkProgram(c->nspace, c->curprg->def);
	if (c->curprg->def->errors) {
		showErrors();
		GDKfatal("Failed to initialise system");
		return 0;
	}
	MALengine(c);
	return 1;
}



#line 112 "/export/scratch0/monet/monet.GNU.64.64.d.14791/MonetDB5/src/mal/mal_session.mx"

void
MSinitClientPrg(Client cntxt, str mod, str nme)
{
	InstrPtr p;
	MalBlkPtr mb;
	int i, cnt = 1;

	if (cntxt->curprg && idcmp(nme, cntxt->curprg->name) == 0) {
		mb = cntxt->curprg->def;
		for (i = 1; i < mb->stop; i++)
			if (mb->stmt[i]->token == REMsymbol)
				cnt++;
		if (mb->stop <= cnt + 1) {	/* complete comments */
			mb->typefixed = 0;
			mb->flowfixed = 0;
			mb->stop = 1;
			cntxt->glb = 0;
			return;
		}
	}
	cntxt->curprg = newFunction(putName(nme, strlen(nme)), FUNCTIONsymbol);
	mb = cntxt->curprg->def;
	p = getSignature(cntxt->curprg);
	if( mod )
		setModuleId(p,mod);
	else
		setModuleScope(p, cntxt->nspace);
	setVarType(mb, findVariable(mb, nme), TYPE_void);
	insertSymbol(cntxt->nspace, cntxt->curprg);
	cntxt->glb = 0;
	assert(cntxt->curprg->def != NULL);
}



#line 147 "/export/scratch0/monet/monet.GNU.64.64.d.14791/MonetDB5/src/mal/mal_session.mx"


#line 161 "/export/scratch0/monet/monet.GNU.64.64.d.14791/MonetDB5/src/mal/mal_session.mx"
void
MSscheduleClient(str command, str challenge, bstream *fin, stream *fout)
{
	char *user = command, *algo = NULL, *passwd = NULL, *lang = NULL;
	char *database = NULL, *s;
	int key = 0;
	Client c;
	MT_Id p;

	/* decode BIG/LIT:user:{cypher}passwordchal:lang:database: line */

	/* byte order */
	s = strchr(user, ':');
	if (s) {
		*s = 0;
		stream_set_byteorder(fin->s, strcmp(user, "BIG") == 0);
		user = s + 1;
	} else {
		stream_printf(fout, "!incomplete challenge '%s'\n", user);
		stream_flush(fout);
		GDKfree(command);
		return;
	}

	/* passwd */
	s = strchr(user, ':');
	if (s) {
		*s = 0;
		passwd = s + 1;
		/* decode algorithm, i.e. {plain}mypasswordchallenge */
		if (*passwd != '{') {
			stream_printf(fout, "!invalid password entry\n");
			stream_flush(fout);
			GDKfree(command);
			return;
		}
		algo = passwd + 1;
		s = strchr(algo, '}');
		if (!s) {
			stream_printf(fout, "!invalid password entry\n");
			stream_flush(fout);
			GDKfree(command);
			return;
		}
		*s = 0;
		passwd = s + 1;
	} else {
		stream_printf(fout, "!incomplete challenge '%s'\n", user);
		stream_flush(fout);
		GDKfree(command);
		return;
	}

	/* lang */
	s = strchr(passwd, ':');
	if (s) {
		*s = 0;
		lang = s + 1;
	} else {
		stream_printf(fout, "!incomplete challenge, missing language\n");
		stream_flush(fout);
		GDKfree(command);
		return;
	}

	/* database */
	s = strchr(lang, ':');
	if (s) {
		*s = 0;
		database = s + 1;
		/* we can have stuff following, make it void */
		s = strchr(database, ':');
		if (s)
			*s = 0;
	}

	if (database && database[0] != '\0' &&
			strcmp(database, GDKgetenv("gdk_dbname")) != 0)
	{
		DIR *d;
		struct dirent *e;
		int found = 0;
		str buf = alloca(sizeof(char) * (PATHLENGTH + 1));
		str p;
		int len;
		FILE *f;
		str err = NULL;
		str redir;

		buf[PATHLENGTH] = '\0';
		/* scan the parent for directories */
		d = opendir("..");
		while ((e = readdir(d)) != NULL) {
			/* skip if not the database we're looking for */
			if (strcmp(e->d_name, database) != 0)
				continue;

			/* ok, look for some files we're interested in, start
			 * checking if the server is connectable */
			snprintf(buf, PATHLENGTH, "../%s/.conn", e->d_name);
			if ((f = fopen(buf, "r")) == NULL) {
				err = "database not available or cannot be connected to";
				break;	/* we don't have to look further any more */
			}
			if ((len = fread(buf, 1, PATHLENGTH, f)) <= 0) {
				/* ok, won't work */
				fclose(f);
				err = "database cannot be connected to";
				break;
			}
			buf[len] = '\0';
			/* note: in theory, multiple addresses can be in this file.
			 * We ignore this for now, and just connect to the first one */
			if ((p = strchr(buf, '\n')) == NULL) {
				/* somehow doesn't work */
				fclose(f);
				err = "database cannot be connected to";
				break;
			}
			*p = '\0';
			fclose(f);

			/* alloc some space */
			redir = alloca(sizeof(char) * (strlen(buf) + 2));
			sprintf(redir, "^%s", buf);

			/* see if the server supports the language we're asking for */
			snprintf(buf, PATHLENGTH, "../%s/.scen", e->d_name);
			if ((f = fopen(buf, "r")) == NULL) {
				err = "language not supported";
				break;
			}
			if ((len = fread(buf, 1, PATHLENGTH, f)) <= 0) {
				/* ok, won't work */
				fclose(f);
				err = "database cannot be connected to";
				break;
			}
			buf[len] = '\0';
			while ((p = strchr(buf, '\n')) != NULL) {
				*p = '\0';
				if (strcmp(buf, lang) == 0) {
					found = 1;
					break;
				}
				buf = p + 1;
			}
			fclose(f);

			if (found == 1) {
				stream_printf(fout, "%s%s?lang=%s&user=%s\n",
						redir, database, buf, user);
				/* flush redirect and return */
				stream_flush(fout);
				closedir(d);
				GDKfree(command);
				return;
			} else {
				err = "language not supported";
				break;
			}
		}	
		(void) closedir(d);
		if (err == NULL) err = "database does not exist";
		stream_printf(fout, "!redirect to database '%s': %s\n", database, err);
		/* flush the error to the client, and abort further execution */
		stream_flush(fout);
		GDKfree(command);
		return;
	} else {
		str err;
		oid uid;

		/* access control: verify the credentials supplied by the user,
		 * no need to check for database stuff, because that is done per
		 * database itself (one gets a redirect) */
		err = AUTHcheckCredentials(&uid, &user, &passwd, &challenge, &algo, &lang);
		if (err != MAL_SUCCEED) {
			stream_printf(fout, "!%s\n", err);
			stream_flush(fout);
			GDKfree(command);
			return;
		}

		c = MCinitClient(uid, fin, fout);
		if (c == NULL) {
			stream_printf(fout, "!Out of client slots\n");
			stream_flush(fout);
			GDKfree(command);
			return;
		}
		c->nspace = newModule(NULL, putName("user", 4));
		c->nspace->outer = mal_scope;
		c->sessionkey = key;

		if (!lang) {
			if ((s = defaultScenario(c))) {
				stream_printf(c->fdout, "!%s\n", s);
				stream_flush(c->fdout);
				c->mode = FINISHING;
			}
		} else if ((s = setScenario(c, lang)) != NULL) {
			stream_printf(c->fdout, "!%s\n", s);
			stream_flush(c->fdout);
			c->mode = FINISHING;
		}
	}

	MSinitClientPrg(c,"user", "main");

	GDKfree(command);
	if (MT_create_thread(&p, MSserveClient, (void *) c) < 0) {
		showException(MAL,"initClient", "can not fork new client");
		return;
	}
}



#line 400 "/export/scratch0/monet/monet.GNU.64.64.d.14791/MonetDB5/src/mal/mal_session.mx"
void
MSresetInstructions(MalBlkPtr mb, int start)
{
	int i;
	InstrPtr p;

	for (i = start; i < mb->stop; i++) {
		p = getInstrPtr(mb, i);
		if (p)
			freeInstruction(p);
		mb->stmt[i] = NULL;
	}
	mb->stop = start;
}

static int unknownType(int tpe){
	return tpe == TYPE_any || 
		(isaBatType(tpe) && (
			getHeadType(tpe) == TYPE_any || 
			getTailType(tpe) == TYPE_any ));
}
void
MSresetVariables(MalBlkPtr mb, MalStkPtr glb, int start)
{
	int i, j;

	for (i = j = start; i < mb->vtop;) {
		if (isTmpVar(mb, i) || unknownType(getVarType(mb,i)) ) {
			clearVariable(mb, i);

			if (glb) {
				garbageElement(&glb->stk[i]);
				/* clean stack entry */
				glb->stk[i].vtype = TYPE_int;
				glb->stk[i].val.ival = 0;
				glb->stk[i].len = 0;
			}
			i++;
		} else {
			if (i != j) {
				VarPtr v= getVar(mb,j);
				mb->var[j]= mb->var[i];
				getVar(mb,i)= v;
				if (glb) {
					/* save stack state */
					glb->stk[j] = glb->stk[i];
					/* clean stack entry */
					glb->stk[i].vtype = TYPE_int;
					glb->stk[i].val.ival = 0;
					glb->stk[i].len = 0;
				}
			}
			i++;
			j++;
		}
	}
	mb->vtop = j;
}



#line 465 "/export/scratch0/monet/monet.GNU.64.64.d.14791/MonetDB5/src/mal/mal_session.mx"
void
MSserveClient(void *dummy)
{
	MalBlkPtr mb;
	Client c = (Client) dummy;
	str msg = 0;

	if (!isAdministrator(c))
		MCinitClientThread(c);


#line 478 "/export/scratch0/monet/monet.GNU.64.64.d.14791/MonetDB5/src/mal/mal_session.mx"
	mb = c->curprg->def;
	c->glb = newGlobalStack(MAXGLOBALS + mb->vsize);
	c->glb->stktop = mb->vtop;
	c->glb->blk = mb;

	if (c->scenario == 0)
		msg = defaultScenario(c);
	if (msg) {
		showException(MAL, "serveClient", "could not initialize default scenario");
		c->mode = FINISHING + 1;
	} else
		do {
			runScenario(c);
			if (c->mode == FINISHING)
				break;
			resetScenario(c);
		} while (c->scenario);


#line 498 "/export/scratch0/monet/monet.GNU.64.64.d.14791/MonetDB5/src/mal/mal_session.mx"
	freeMalBlk(c->curprg->def);
	c->curprg->def = 0;

	if (c->mode > FINISHING) {
		if (isAdministrator(c)) {
			/* old OIDflushdelta =0; */
			if (c->scenario) {
				exitScenario(c);
			}
		}
	}
	if (!isAdministrator(c))
		MCcloseClient(c);
}



#line 533 "/export/scratch0/monet/monet.GNU.64.64.d.14791/MonetDB5/src/mal/mal_session.mx"
str
MALexitSession(Client c)
{
	(void) c;
	return 0;
}
str
MALexitClient(Client c)
{
	if (c->glb) {
		garbageCollector(c->curprg->def, c->glb,TRUE);
		GDKfree(c->glb);
	}
	c->glb = 0;
	return 0;
}

str
MALreader(Client c)
{
	int r= 1;

	c->fdin->pos += c->yycur;
	c->yycur = 0;
	c->fdin->buf[c->fdin->pos] = 0;

	if( c == mal_clients){
		r= readConsole(c);
		if (r <0 && c->fdin->eof == 0 )
			r= MCreadClient(c);
		if( r > 0)
			return MAL_SUCCEED;
	} else
	if (MCreadClient(c) > 0)
		return MAL_SUCCEED;
	c->mode = FINISHING;
	if (c->fdin)
		c->fdin->buf[c->fdin->pos] = 0;
	else
		throw(MAL, "MAL.reader", "Attempt to read beyond end of file");
	return MAL_SUCCEED;
}

str
MALparser(Client c)
{
	InstrPtr p;
	MalBlkRecord oldstate;

	c->curprg->def->errors = 0;
	oldstate = *c->curprg->def;

	prepareMalBlk(c->curprg->def, CURRENT(c));
	if (parseMAL(c, c->curprg) || c->curprg->def->errors) {
		/* just complete it for visibility */
		pushEndInstruction(c->curprg->def);
		/* catched errors */
		showErrors();
		
#line 525 "/export/scratch0/monet/monet.GNU.64.64.d.14791/MonetDB5/src/mal/mal_session.mx"
	if( c->listing) 
		printFunction(c->fdout,c->curprg->def, c->listing);
	resetMalBlk(c->curprg->def,oldstate.stop);
/*
	MSresetInstructions(c->curprg->def, oldstate.stop);
*/
	MSresetVariables(c->curprg->def, 0, oldstate.vtop);


#line 591 "/export/scratch0/monet/monet.GNU.64.64.d.14791/MonetDB5/src/mal/mal_session.mx"

		throw(SYNTAX, "MAL.parser", "Syntax errors detected");
	}
	/* check for unfinished blocks */
	if (c->blkmode)
		return MAL_SUCCEED;
	/* empty files should be skipped as well */
	if (c->curprg->def->stop == 1)
		return MAL_SUCCEED;

	p = getInstrPtr(c->curprg->def, 0);
	if (p->token != FUNCTIONsymbol) {
		
#line 525 "/export/scratch0/monet/monet.GNU.64.64.d.14791/MonetDB5/src/mal/mal_session.mx"
	if( c->listing) 
		printFunction(c->fdout,c->curprg->def, c->listing);
	resetMalBlk(c->curprg->def,oldstate.stop);
/*
	MSresetInstructions(c->curprg->def, oldstate.stop);
*/
	MSresetVariables(c->curprg->def, 0, oldstate.vtop);


#line 603 "/export/scratch0/monet/monet.GNU.64.64.d.14791/MonetDB5/src/mal/mal_session.mx"

		throw(MAL, "MAL.parser", "Function signature missing");
	}
	pushEndInstruction(c->curprg->def);
	trimMalBlk(c->curprg->def);
	chkProgram(c->nspace, c->curprg->def);
	if (c->curprg->def->errors) {
		showErrors();
		
#line 525 "/export/scratch0/monet/monet.GNU.64.64.d.14791/MonetDB5/src/mal/mal_session.mx"
	if( c->listing) 
		printFunction(c->fdout,c->curprg->def, c->listing);
	resetMalBlk(c->curprg->def,oldstate.stop);
/*
	MSresetInstructions(c->curprg->def, oldstate.stop);
*/
	MSresetVariables(c->curprg->def, 0, oldstate.vtop);


#line 611 "/export/scratch0/monet/monet.GNU.64.64.d.14791/MonetDB5/src/mal/mal_session.mx"

		throw(MAL, "MAL.parser", "Semantic errors detected");
	}
	return MAL_SUCCEED;
}

int
MALcommentsOnly(MalBlkPtr mb)
{
	int i;

	for (i = 1; i < mb->stop; i++)
		if (mb->stmt[i]->token != REMsymbol)
			return 0;
	return 1;
}

str
MALengine(Client c)
{
	Symbol prg;
	str msg = 0;
	MalBlkRecord oldstate;

	oldstate.stop = 0;
	oldstate.vtop = 0;

	if( c->blkmode)
		return MAL_SUCCEED;
	prg = c->curprg;
	if (prg == NULL)
		throw(MAL, "MAL.engine", "Main MAL function missing");

	if (prg->def->errors > 0) {
		showErrors();
		
#line 525 "/export/scratch0/monet/monet.GNU.64.64.d.14791/MonetDB5/src/mal/mal_session.mx"
	if( c->listing) 
		printFunction(c->fdout,c->curprg->def, c->listing);
	resetMalBlk(c->curprg->def,oldstate.stop);
/*
	MSresetInstructions(c->curprg->def, oldstate.stop);
*/
	MSresetVariables(c->curprg->def, 0, oldstate.vtop);


#line 646 "/export/scratch0/monet/monet.GNU.64.64.d.14791/MonetDB5/src/mal/mal_session.mx"

		throw(MAL, "MAL.engine", "Program contains errors");
	}
	if (prg->def->stop == 1 || MALcommentsOnly(prg->def))
		return 0;	/* empty block */
	if (c->glb) {
		if (prg->def && c->glb->stksize < prg->def->vsize)
			c->glb = reallocGlobalStack(c->glb, prg->def->vsize);
		c->glb->stktop = prg->def->vtop;
		c->glb->blk = prg->def;
		c->glb->cmd = (c->itrace && c->itrace != 'C') ? 'n' : 0;
	}

	if (c->listing)
		printFunction(c->fdout, c->curprg->def, c->listing);


#line 666 "/export/scratch0/monet/monet.GNU.64.64.d.14791/MonetDB5/src/mal/mal_session.mx"
	if (c->glb){
		c->glb->pcup = 0;
		c->glb->keepAlive= TRUE; /* no garbage collection */
	}
	if (prg->def->errors == 0)
		msg = (str) runMAL(c, prg->def, 1, 0, c->glb, 0);
	else
		msg = MAL_SUCCEED;
	if (msg) {
		str place = getExceptionPlace(msg);
		showException(getExceptionType(msg), place, getExceptionMessage(msg));
		GDKfree(place);
		if (!c->listing)
			printFunction(c->fdout, c->curprg->def, c->listing);
		showErrors();
	}
	resetMalBlk(prg->def,1);
	MSresetVariables(prg->def, c->glb, 0);
	prg->def->errors = 0;
	return msg;
}



#line 689 "/export/scratch0/monet/monet.GNU.64.64.d.14791/MonetDB5/src/mal/mal_session.mx"