1 /****************************************************************************
2 * RRDtool 1.0.28 Copyright Tobias Oetiker, 1997 - 2002
3 ****************************************************************************
4 * rrd_rpncalc.c RPN calculator functions
5 ****************************************************************************/
7 #include "rrd_tool.h"
8 #include "rrd_rpncalc.h"
9 #include "rrd_graph.h"
10 #include <limits.h>
12 short addop2str(enum op_en op, enum op_en op_type, char *op_str,
13 char **result_str, unsigned short *offset);
14 int tzoffset(time_t); /* used to implement LTIME */
16 short rpn_compact(rpnp_t *rpnp, rpn_cdefds_t **rpnc, short *count)
17 {
18 short i;
19 *count = 0;
20 /* count the number of rpn nodes */
21 while(rpnp[*count].op != OP_END) (*count)++;
22 if (++(*count) > DS_CDEF_MAX_RPN_NODES) {
23 rrd_set_error("Maximum %d RPN nodes permitted",
24 DS_CDEF_MAX_RPN_NODES);
25 return -1;
26 }
28 /* allocate memory */
29 *rpnc = (rpn_cdefds_t *) calloc(*count,sizeof(rpn_cdefds_t));
30 for (i = 0; rpnp[i].op != OP_END; i++)
31 {
32 (*rpnc)[i].op = (char) rpnp[i].op;
33 if (rpnp[i].op == OP_NUMBER) {
34 /* rpnp.val is a double, rpnc.val is a short */
35 double temp = floor(rpnp[i].val);
36 if (temp < SHRT_MIN || temp > SHRT_MAX) {
37 rrd_set_error(
38 "constants must be integers in the interval (%d, %d)",
39 SHRT_MIN, SHRT_MAX);
40 free(*rpnc);
41 return -1;
42 }
43 (*rpnc)[i].val = (short) temp;
44 } else if (rpnp[i].op == OP_VARIABLE ||
45 rpnp[i].op == OP_PREV_OTHER) {
46 (*rpnc)[i].val = (short) rpnp[i].ptr;
47 }
48 }
49 /* terminate the sequence */
50 (*rpnc)[(*count) - 1].op = OP_END;
51 return 0;
52 }
54 rpnp_t * rpn_expand(rpn_cdefds_t *rpnc)
55 {
56 short i;
57 rpnp_t *rpnp;
59 /* DS_CDEF_MAX_RPN_NODES is small, so at the expense of some wasted
60 * memory we avoid any reallocs */
61 rpnp = (rpnp_t *) calloc(DS_CDEF_MAX_RPN_NODES,sizeof(rpnp_t));
62 if (rpnp == NULL) return NULL;
63 for (i = 0; rpnc[i].op != OP_END; ++i)
64 {
65 rpnp[i].op = (long) rpnc[i].op;
66 if (rpnp[i].op == OP_NUMBER) {
67 rpnp[i].val = (double) rpnc[i].val;
68 } else if (rpnp[i].op == OP_VARIABLE ||
69 rpnp[i].op == OP_PREV_OTHER) {
70 rpnp[i].ptr = (long) rpnc[i].val;
71 }
72 }
73 /* terminate the sequence */
74 rpnp[i].op = OP_END;
75 return rpnp;
76 }
78 /* rpn_compact2str: convert a compact sequence of RPN operator nodes back
79 * into a CDEF string. This function is used by rrd_dump.
80 * arguments:
81 * rpnc: an array of compact RPN operator nodes
82 * ds_def: a pointer to the data source definition section of an RRD header
83 * for lookup of data source names by index
84 * str: out string, memory is allocated by the function, must be freed by the
85 * the caller */
86 void rpn_compact2str(rpn_cdefds_t *rpnc,ds_def_t *ds_def,char **str)
87 {
88 unsigned short i,offset = 0;
89 char buffer[7]; /* short as a string */
91 for (i = 0; rpnc[i].op != OP_END; i++)
92 {
93 if (i > 0) (*str)[offset++] = ',';
95 #define add_op(VV,VVV) \
96 if (addop2str(rpnc[i].op, VV, VVV, str, &offset) == 1) continue;
98 if (rpnc[i].op == OP_NUMBER) {
99 /* convert a short into a string */
100 #ifdef WIN32
101 _itoa(rpnc[i].val,buffer,10);
102 #else
103 sprintf(buffer,"%d",rpnc[i].val);
104 #endif
105 add_op(OP_NUMBER,buffer)
106 }
108 if (rpnc[i].op == OP_VARIABLE) {
109 char *ds_name = ds_def[rpnc[i].val].ds_nam;
110 add_op(OP_VARIABLE, ds_name)
111 }
113 if (rpnc[i].op == OP_PREV_OTHER) {
114 char *ds_name = ds_def[rpnc[i].val].ds_nam;
115 add_op(OP_VARIABLE, ds_name)
116 }
118 #undef add_op
120 #define add_op(VV,VVV) \
121 if (addop2str(rpnc[i].op, VV, #VVV, str, &offset) == 1) continue;
123 add_op(OP_ADD,+)
124 add_op(OP_SUB,-)
125 add_op(OP_MUL,*)
126 add_op(OP_DIV,/)
127 add_op(OP_MOD,%)
128 add_op(OP_SIN,SIN)
129 add_op(OP_COS,COS)
130 add_op(OP_LOG,LOG)
131 add_op(OP_FLOOR,FLOOR)
132 add_op(OP_CEIL,CEIL)
133 add_op(OP_EXP,EXP)
134 add_op(OP_DUP,DUP)
135 add_op(OP_EXC,EXC)
136 add_op(OP_POP,POP)
137 add_op(OP_LT,LT)
138 add_op(OP_LE,LE)
139 add_op(OP_GT,GT)
140 add_op(OP_GE,GE)
141 add_op(OP_EQ,EQ)
142 add_op(OP_IF,IF)
143 add_op(OP_MIN,MIN)
144 add_op(OP_MAX,MAX)
145 add_op(OP_LIMIT,LIMIT)
146 add_op(OP_UNKN,UNKN)
147 add_op(OP_UN,UN)
148 add_op(OP_NEGINF,NEGINF)
149 add_op(OP_NE,NE)
150 add_op(OP_PREV,PREV)
151 add_op(OP_INF,INF)
152 add_op(OP_ISINF,ISINF)
153 add_op(OP_NOW,NOW)
154 add_op(OP_LTIME,LTIME)
155 add_op(OP_TIME,TIME)
157 #undef add_op
158 }
159 (*str)[offset] = '\0';
161 }
163 short addop2str(enum op_en op, enum op_en op_type, char *op_str,
164 char **result_str, unsigned short *offset)
165 {
166 if (op == op_type) {
167 short op_len;
168 op_len = strlen(op_str);
169 *result_str = (char *) rrd_realloc(*result_str,
170 (op_len + 1 + *offset)*sizeof(char));
171 if (*result_str == NULL) {
172 rrd_set_error("failed to alloc memory in addop2str");
173 return -1;
174 }
175 strncpy(&((*result_str)[*offset]),op_str,op_len);
176 *offset += op_len;
177 return 1;
178 }
179 return 0;
180 }
182 void parseCDEF_DS(char *def,rrd_t *rrd, int ds_idx)
183 {
184 rpnp_t *rpnp = NULL;
185 rpn_cdefds_t *rpnc = NULL;
186 short count, i;
188 rpnp = rpn_parse((void*) rrd, def, &lookup_DS);
189 if (rpnp == NULL) {
190 rrd_set_error("failed to parse computed data source %s", def);
191 return;
192 }
193 /* Check for OP nodes not permitted in COMPUTE DS.
194 * Moved this check from within rpn_compact() because it really is
195 * COMPUTE DS specific. This is less efficient, but creation doesn't
196 * occur too often. */
197 for (i = 0; rpnp[i].op != OP_END; i++) {
198 if (rpnp[i].op == OP_TIME || rpnp[i].op == OP_LTIME ||
199 rpnp[i].op == OP_PREV || rpnp[i].op == OP_COUNT)
200 {
201 rrd_set_error(
202 "operators time, ltime, prev and count not supported with DS COMPUTE");
203 free(rpnp);
204 return;
205 }
206 }
207 if (rpn_compact(rpnp,&rpnc,&count) == -1) {
208 free(rpnp);
209 return;
210 }
211 /* copy the compact rpn representation over the ds_def par array */
212 memcpy((void*) &(rrd -> ds_def[ds_idx].par[DS_cdef]),
213 (void*) rpnc, count*sizeof(rpn_cdefds_t));
214 free(rpnp);
215 free(rpnc);
216 }
218 /* lookup a data source name in the rrd struct and return the index,
219 * should use ds_match() here except:
220 * (1) need a void * pointer to the rrd
221 * (2) error handling is left to the caller
222 */
223 long lookup_DS(void *rrd_vptr,char *ds_name)
224 {
225 unsigned int i;
226 rrd_t *rrd;
228 rrd = (rrd_t *) rrd_vptr;
230 for (i = 0; i < rrd -> stat_head -> ds_cnt; ++i)
231 {
232 if(strcmp(ds_name,rrd -> ds_def[i].ds_nam) == 0)
233 return i;
234 }
235 /* the caller handles a bad data source name in the rpn string */
236 return -1;
237 }
239 /* rpn_parse : parse a string and generate a rpnp array; modified
240 * str2rpn() originally included in rrd_graph.c
241 * arguments:
242 * key_hash: a transparent argument passed to lookup(); conceptually this
243 * is a hash object for lookup of a numeric key given a variable name
244 * expr: the string RPN expression, including variable names
245 * lookup(): a function that retrieves a numeric key given a variable name
246 */
247 rpnp_t *
248 rpn_parse(void *key_hash,char *expr,long (*lookup)(void *,char*)){
249 int pos=0;
250 long steps=-1;
251 rpnp_t *rpnp;
252 char vname[30];
254 rpnp=NULL;
256 while(*expr){
257 if ((rpnp = (rpnp_t *) rrd_realloc(rpnp, (++steps + 2)*
258 sizeof(rpnp_t)))==NULL){
259 return NULL;
260 }
262 else if((sscanf(expr,"%lf%n",&rpnp[steps].val,&pos) == 1) && (expr[pos] == ',')){
263 rpnp[steps].op = OP_NUMBER;
264 expr+=pos;
265 }
267 #define match_op(VV,VVV) \
268 else if (strncmp(expr, #VVV, strlen(#VVV))==0){ \
269 rpnp[steps].op = VV; \
270 expr+=strlen(#VVV); \
271 }
274 #define match_op_param(VV,VVV) \
275 else if (sscanf(expr, #VVV "(" DEF_NAM_FMT ")",vname) == 1) { \
276 int length = 0; \
277 if ((length = strlen(#VVV)+strlen(vname)+2, \
278 expr[length] == ',' || expr[length] == '\0') ) { \
279 rpnp[steps].op = VV; \
280 rpnp[steps].ptr = (*lookup)(key_hash,vname); \
281 if (rpnp[steps].ptr < 0) { \
282 free(rpnp); \
283 return NULL; \
284 } else expr+=length; \
285 } \
286 }
288 match_op(OP_ADD,+)
289 match_op(OP_SUB,-)
290 match_op(OP_MUL,*)
291 match_op(OP_DIV,/)
292 match_op(OP_MOD,%)
293 match_op(OP_SIN,SIN)
294 match_op(OP_COS,COS)
295 match_op(OP_LOG,LOG)
296 match_op(OP_FLOOR,FLOOR)
297 match_op(OP_CEIL,CEIL)
298 match_op(OP_EXP,EXP)
299 match_op(OP_DUP,DUP)
300 match_op(OP_EXC,EXC)
301 match_op(OP_POP,POP)
302 match_op(OP_LT,LT)
303 match_op(OP_LE,LE)
304 match_op(OP_GT,GT)
305 match_op(OP_GE,GE)
306 match_op(OP_EQ,EQ)
307 match_op(OP_IF,IF)
308 match_op(OP_MIN,MIN)
309 match_op(OP_MAX,MAX)
310 match_op(OP_LIMIT,LIMIT)
311 /* order is important here ! .. match longest first */
312 match_op(OP_UNKN,UNKN)
313 match_op(OP_UN,UN)
314 match_op(OP_NEGINF,NEGINF)
315 match_op(OP_NE,NE)
316 match_op(OP_COUNT,COUNT)
317 match_op_param(OP_PREV_OTHER,PREV)
318 match_op(OP_PREV,PREV)
319 match_op(OP_INF,INF)
320 match_op(OP_ISINF,ISINF)
321 match_op(OP_NOW,NOW)
322 match_op(OP_LTIME,LTIME)
323 match_op(OP_TIME,TIME)
325 #undef match_op
328 else if ((sscanf(expr, DEF_NAM_FMT "%n",
329 vname,&pos) == 1)
330 && ((rpnp[steps].ptr = (*lookup)(key_hash,vname)) != -1)){
331 rpnp[steps].op = OP_VARIABLE;
332 expr+=pos;
333 }
335 else {
336 free(rpnp);
337 return NULL;
338 }
339 if (*expr == 0)
340 break;
341 if (*expr == ',')
342 expr++;
343 else {
344 free(rpnp);
345 return NULL;
346 }
347 }
348 rpnp[steps+1].op = OP_END;
349 return rpnp;
350 }
352 void
353 rpnstack_init(rpnstack_t *rpnstack)
354 {
355 rpnstack -> s = NULL;
356 rpnstack -> dc_stacksize = 0;
357 rpnstack -> dc_stackblock = 100;
358 }
360 void
361 rpnstack_free(rpnstack_t *rpnstack)
362 {
363 if (rpnstack -> s != NULL)
364 free(rpnstack -> s);
365 rpnstack -> dc_stacksize = 0;
366 }
368 /* rpn_calc: run the RPN calculator; also performs variable substitution;
369 * moved and modified from data_calc() originally included in rrd_graph.c
370 * arguments:
371 * rpnp : an array of RPN operators (including variable references)
372 * rpnstack : the initialized stack
373 * data_idx : when data_idx is a multiple of rpnp.step, the rpnp.data pointer
374 * is advanced by rpnp.ds_cnt; used only for variable substitution
375 * output : an array of output values; OP_PREV assumes this array contains
376 * the "previous" value at index position output_idx-1; the definition of
377 * "previous" depends on the calling environment
378 * output_idx : an index into the output array in which to store the output
379 * of the RPN calculator
380 * returns: -1 if the computation failed (also calls rrd_set_error)
381 * 0 on success
382 */
383 short
384 rpn_calc(rpnp_t *rpnp, rpnstack_t *rpnstack, long data_idx,
385 rrd_value_t *output, int output_idx)
386 {
387 int rpi;
388 long stptr = -1;
390 /* process each op from the rpn in turn */
391 for (rpi=0; rpnp[rpi].op != OP_END; rpi++){
392 /* allocate or grow the stack */
393 if (stptr + 5 > rpnstack -> dc_stacksize){
394 /* could move this to a separate function */
395 rpnstack -> dc_stacksize += rpnstack -> dc_stackblock;
396 rpnstack -> s = rrd_realloc(rpnstack -> s,
397 (rpnstack -> dc_stacksize)*sizeof(*(rpnstack -> s)));
398 if (rpnstack -> s == NULL){
399 rrd_set_error("RPN stack overflow");
400 return -1;
401 }
402 }
404 #define stackunderflow(MINSIZE) \
405 if(stptr<MINSIZE){ \
406 rrd_set_error("RPN stack underflow"); \
407 return -1; \
408 }
410 switch (rpnp[rpi].op){
411 case OP_NUMBER:
412 rpnstack -> s[++stptr] = rpnp[rpi].val;
413 break;
414 case OP_VARIABLE:
415 /* Sanity check: VDEFs shouldn't make it here */
416 if (rpnp[rpi].ds_cnt == 0) {
417 rrd_set_error("VDEF made it into rpn_calc... aborting");
418 return -1;
419 } else {
420 /* make sure we pull the correct value from
421 * the *.data array. Adjust the pointer into
422 * the array acordingly. Advance the ptr one
423 * row in the rra (skip over non-relevant
424 * data sources)
425 */
426 rpnstack -> s[++stptr] = *(rpnp[rpi].data);
427 if (data_idx % rpnp[rpi].step == 0){
428 rpnp[rpi].data += rpnp[rpi].ds_cnt;
429 }
430 }
431 break;
432 case OP_COUNT:
433 rpnstack -> s[++stptr] = (output_idx+1); /* Note: Counter starts at 1 */
434 break;
435 case OP_PREV:
436 if ((output_idx) <= 0) {
437 rpnstack -> s[++stptr] = DNAN;
438 } else {
439 rpnstack -> s[++stptr] = output[output_idx-1];
440 }
441 break;
442 case OP_PREV_OTHER:
443 if ((output_idx) <= 0) {
444 rpnstack -> s[++stptr] = DNAN;
445 } else {
446 rpnstack -> s[++stptr] = rpnp[rpnp[rpi].ptr].data[output_idx-1];
447 }
448 break;
449 case OP_UNKN:
450 rpnstack -> s[++stptr] = DNAN;
451 break;
452 case OP_INF:
453 rpnstack -> s[++stptr] = DINF;
454 break;
455 case OP_NEGINF:
456 rpnstack -> s[++stptr] = -DINF;
457 break;
458 case OP_NOW:
459 rpnstack -> s[++stptr] = (double)time(NULL);
460 break;
461 case OP_TIME:
462 /* HACK: this relies on the data_idx being the time,
463 ** which the within-function scope is unaware of */
464 rpnstack -> s[++stptr] = (double) data_idx;
465 break;
466 case OP_LTIME:
467 rpnstack -> s[++stptr] =
468 (double) tzoffset(data_idx) + (double)data_idx;
469 break;
470 case OP_ADD:
471 stackunderflow(1);
472 rpnstack -> s[stptr-1] = rpnstack -> s[stptr-1]
473 + rpnstack -> s[stptr];
474 stptr--;
475 break;
476 case OP_SUB:
477 stackunderflow(1);
478 rpnstack -> s[stptr-1] = rpnstack -> s[stptr-1]
479 - rpnstack -> s[stptr];
480 stptr--;
481 break;
482 case OP_MUL:
483 stackunderflow(1);
484 rpnstack -> s[stptr-1] = (rpnstack -> s[stptr-1])
485 * (rpnstack -> s[stptr]);
486 stptr--;
487 break;
488 case OP_DIV:
489 stackunderflow(1);
490 rpnstack -> s[stptr-1] = rpnstack -> s[stptr-1]
491 / rpnstack -> s[stptr];
492 stptr--;
493 break;
494 case OP_MOD:
495 stackunderflow(1);
496 rpnstack -> s[stptr-1]= fmod( rpnstack -> s[stptr-1]
497 ,rpnstack -> s[stptr]);
498 stptr--;
499 break;
500 case OP_SIN:
501 stackunderflow(0);
502 rpnstack -> s[stptr] = sin(rpnstack -> s[stptr]);
503 break;
504 case OP_COS:
505 stackunderflow(0);
506 rpnstack -> s[stptr] = cos(rpnstack -> s[stptr]);
507 break;
508 case OP_CEIL:
509 stackunderflow(0);
510 rpnstack -> s[stptr] = ceil(rpnstack -> s[stptr]);
511 break;
512 case OP_FLOOR:
513 stackunderflow(0);
514 rpnstack -> s[stptr] = floor(rpnstack -> s[stptr]);
515 break;
516 case OP_LOG:
517 stackunderflow(0);
518 rpnstack -> s[stptr] = log(rpnstack -> s[stptr]);
519 break;
520 case OP_DUP:
521 stackunderflow(0);
522 rpnstack -> s[stptr+1] = rpnstack -> s[stptr];
523 stptr++;
524 break;
525 case OP_POP:
526 stackunderflow(0);
527 stptr--;
528 break;
529 case OP_EXC:
530 stackunderflow(1);
531 {
532 double dummy;
533 dummy = rpnstack -> s[stptr] ;
534 rpnstack -> s[stptr] = rpnstack -> s[stptr-1];
535 rpnstack -> s[stptr-1] = dummy;
536 }
537 break;
538 case OP_EXP:
539 stackunderflow(0);
540 rpnstack -> s[stptr] = exp(rpnstack -> s[stptr]);
541 break;
542 case OP_LT:
543 stackunderflow(1);
544 if (isnan(rpnstack -> s[stptr-1]))
545 ;
546 else if (isnan(rpnstack -> s[stptr]))
547 rpnstack -> s[stptr-1] = rpnstack -> s[stptr];
548 else
549 rpnstack -> s[stptr-1] = rpnstack -> s[stptr-1] <
550 rpnstack -> s[stptr] ? 1.0 : 0.0;
551 stptr--;
552 break;
553 case OP_LE:
554 stackunderflow(1);
555 if (isnan(rpnstack -> s[stptr-1]))
556 ;
557 else if (isnan(rpnstack -> s[stptr]))
558 rpnstack -> s[stptr-1] = rpnstack -> s[stptr];
559 else
560 rpnstack -> s[stptr-1] = rpnstack -> s[stptr-1] <=
561 rpnstack -> s[stptr] ? 1.0 : 0.0;
562 stptr--;
563 break;
564 case OP_GT:
565 stackunderflow(1);
566 if (isnan(rpnstack -> s[stptr-1]))
567 ;
568 else if (isnan(rpnstack -> s[stptr]))
569 rpnstack -> s[stptr-1] = rpnstack -> s[stptr];
570 else
571 rpnstack -> s[stptr-1] = rpnstack -> s[stptr-1] >
572 rpnstack -> s[stptr] ? 1.0 : 0.0;
573 stptr--;
574 break;
575 case OP_GE:
576 stackunderflow(1);
577 if (isnan(rpnstack -> s[stptr-1]))
578 ;
579 else if (isnan(rpnstack -> s[stptr]))
580 rpnstack -> s[stptr-1] = rpnstack -> s[stptr];
581 else
582 rpnstack -> s[stptr-1] = rpnstack -> s[stptr-1] >=
583 rpnstack -> s[stptr] ? 1.0 : 0.0;
584 stptr--;
585 break;
586 case OP_NE:
587 stackunderflow(1);
588 if (isnan(rpnstack -> s[stptr-1]))
589 ;
590 else if (isnan(rpnstack -> s[stptr]))
591 rpnstack -> s[stptr-1] = rpnstack -> s[stptr];
592 else
593 rpnstack -> s[stptr-1] = rpnstack -> s[stptr-1] ==
594 rpnstack -> s[stptr] ? 0.0 : 1.0;
595 stptr--;
596 break;
597 case OP_EQ:
598 stackunderflow(1);
599 if (isnan(rpnstack -> s[stptr-1]))
600 ;
601 else if (isnan(rpnstack -> s[stptr]))
602 rpnstack -> s[stptr-1] = rpnstack -> s[stptr];
603 else
604 rpnstack -> s[stptr-1] = rpnstack -> s[stptr-1] ==
605 rpnstack -> s[stptr] ? 1.0 : 0.0;
606 stptr--;
607 break;
608 case OP_IF:
609 stackunderflow(2);
610 rpnstack->s[stptr-2] = rpnstack->s[stptr-2] != 0.0 ?
611 rpnstack->s[stptr-1] : rpnstack->s[stptr];
612 stptr--;
613 stptr--;
614 break;
615 case OP_MIN:
616 stackunderflow(1);
617 if (isnan(rpnstack->s[stptr-1]))
618 ;
619 else if (isnan(rpnstack->s[stptr]))
620 rpnstack->s[stptr-1] = rpnstack->s[stptr];
621 else if (rpnstack->s[stptr-1] > rpnstack->s[stptr])
622 rpnstack->s[stptr-1] = rpnstack->s[stptr];
623 stptr--;
624 break;
625 case OP_MAX:
626 stackunderflow(1);
627 if (isnan(rpnstack->s[stptr-1]))
628 ;
629 else if (isnan(rpnstack->s[stptr]))
630 rpnstack->s[stptr-1] = rpnstack->s[stptr];
631 else if (rpnstack->s[stptr-1] < rpnstack->s[stptr])
632 rpnstack->s[stptr-1] = rpnstack->s[stptr];
633 stptr--;
634 break;
635 case OP_LIMIT:
636 stackunderflow(2);
637 if (isnan(rpnstack->s[stptr-2]))
638 ;
639 else if (isnan(rpnstack->s[stptr-1]))
640 rpnstack->s[stptr-2] = rpnstack->s[stptr-1];
641 else if (isnan(rpnstack->s[stptr]))
642 rpnstack->s[stptr-2] = rpnstack->s[stptr];
643 else if (rpnstack->s[stptr-2] < rpnstack->s[stptr-1])
644 rpnstack->s[stptr-2] = DNAN;
645 else if (rpnstack->s[stptr-2] > rpnstack->s[stptr])
646 rpnstack->s[stptr-2] = DNAN;
647 stptr-=2;
648 break;
649 case OP_UN:
650 stackunderflow(0);
651 rpnstack->s[stptr] = isnan(rpnstack->s[stptr]) ? 1.0 : 0.0;
652 break;
653 case OP_ISINF:
654 stackunderflow(0);
655 rpnstack->s[stptr] = isinf(rpnstack->s[stptr]) ? 1.0 : 0.0;
656 break;
657 case OP_END:
658 break;
659 }
660 #undef stackunderflow
661 }
662 if(stptr!=0){
663 rrd_set_error("RPN final stack size != 1");
664 return -1;
665 }
667 output[output_idx] = rpnstack->s[0];
668 return 0;
669 }
671 /* figure out what the local timezone offset for any point in
672 time was. Return it in seconds */
673 int
674 tzoffset( time_t now ){
675 int gm_sec, gm_min, gm_hour, gm_yday, gm_year,
676 l_sec, l_min, l_hour, l_yday, l_year;
677 struct tm t;
678 int off;
679 gmtime_r(&now, &t);
680 gm_sec = t.tm_sec;
681 gm_min = t.tm_min;
682 gm_hour = t.tm_hour;
683 gm_yday = t.tm_yday;
684 gm_year = t.tm_year;
685 localtime_r(&now, &t);
686 l_sec = t.tm_sec;
687 l_min = t.tm_min;
688 l_hour = t.tm_hour;
689 l_yday = t.tm_yday;
690 l_year = t.tm_year;
691 off = (l_sec-gm_sec)+(l_min-gm_min)*60+(l_hour-gm_hour)*3600;
692 if ( l_yday > gm_yday || l_year > gm_year){
693 off += 24*3600;
694 } else if ( l_yday < gm_yday || l_year < gm_year){
695 off -= 24*3600;
696 }
697 return off;
698 }