1 /*
2 * Copyright (c) 2009-2012, Salvatore Sanfilippo <antirez at gmail dot com>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are met:
7 *
8 * * Redistributions of source code must retain the above copyright notice,
9 * this list of conditions and the following disclaimer.
10 * * Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * * Neither the name of Redis nor the names of its contributors may be used
14 * to endorse or promote products derived from this software without
15 * specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
18 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
21 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
22 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
23 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
24 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
25 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
26 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
27 * POSSIBILITY OF SUCH DAMAGE.
28 */
29
30 #include "server.h"
31 #include <math.h> /* isnan(), isinf() */
32
33 /*-----------------------------------------------------------------------------
34 * String Commands
35 *----------------------------------------------------------------------------*/
36
checkStringLength(client * c,long long size)37 static int checkStringLength(client *c, long long size) {
38 if (size > 512*1024*1024) {
39 addReplyError(c,"string exceeds maximum allowed size (512MB)");
40 return C_ERR;
41 }
42 return C_OK;
43 }
44
45 /* The setGenericCommand() function implements the SET operation with different
46 * options and variants. This function is called in order to implement the
47 * following commands: SET, SETEX, PSETEX, SETNX.
48 *
49 * 'flags' changes the behavior of the command (NX or XX, see belove).
50 *
51 * 'expire' represents an expire to set in form of a Redis object as passed
52 * by the user. It is interpreted according to the specified 'unit'.
53 *
54 * 'ok_reply' and 'abort_reply' is what the function will reply to the client
55 * if the operation is performed, or when it is not because of NX or
56 * XX flags.
57 *
58 * If ok_reply is NULL "+OK" is used.
59 * If abort_reply is NULL, "$-1" is used. */
60
61 #define OBJ_SET_NO_FLAGS 0
62 #define OBJ_SET_NX (1<<0) /* Set if key not exists. */
63 #define OBJ_SET_XX (1<<1) /* Set if key exists. */
64 #define OBJ_SET_EX (1<<2) /* Set if time in seconds is given */
65 #define OBJ_SET_PX (1<<3) /* Set if time in ms in given */
66
setGenericCommand(client * c,int flags,robj * key,robj * val,robj * expire,int unit,robj * ok_reply,robj * abort_reply)67 void setGenericCommand(client *c, int flags, robj *key, robj *val, robj *expire, int unit, robj *ok_reply, robj *abort_reply) {
68 long long milliseconds = 0; /* initialized to avoid any harmness warning */
69
70 if (expire) {
71 if (getLongLongFromObjectOrReply(c, expire, &milliseconds, NULL) != C_OK)
72 return;
73 if (milliseconds <= 0) {
74 addReplyErrorFormat(c,"invalid expire time in %s",c->cmd->name);
75 return;
76 }
77 if (unit == UNIT_SECONDS) milliseconds *= 1000;
78 }
79
80 if ((flags & OBJ_SET_NX && lookupKeyWrite(c->db,key) != NULL) ||
81 (flags & OBJ_SET_XX && lookupKeyWrite(c->db,key) == NULL))
82 {
83 addReply(c, abort_reply ? abort_reply : shared.nullbulk);
84 return;
85 }
86 setKey(c->db,key,val);
87 server.dirty++;
88 if (expire) setExpire(c->db,key,mstime()+milliseconds);
89 notifyKeyspaceEvent(NOTIFY_STRING,"set",key,c->db->id);
90 if (expire) notifyKeyspaceEvent(NOTIFY_GENERIC,
91 "expire",key,c->db->id);
92 addReply(c, ok_reply ? ok_reply : shared.ok);
93 }
94
95 /* SET key value [NX] [XX] [EX <seconds>] [PX <milliseconds>] */
setCommand(client * c)96 void setCommand(client *c) {
97 int j;
98 robj *expire = NULL;
99 int unit = UNIT_SECONDS;
100 int flags = OBJ_SET_NO_FLAGS;
101
102 for (j = 3; j < c->argc; j++) {
103 char *a = c->argv[j]->ptr;
104 robj *next = (j == c->argc-1) ? NULL : c->argv[j+1];
105
106 if ((a[0] == 'n' || a[0] == 'N') &&
107 (a[1] == 'x' || a[1] == 'X') && a[2] == '\0' &&
108 !(flags & OBJ_SET_XX))
109 {
110 flags |= OBJ_SET_NX;
111 } else if ((a[0] == 'x' || a[0] == 'X') &&
112 (a[1] == 'x' || a[1] == 'X') && a[2] == '\0' &&
113 !(flags & OBJ_SET_NX))
114 {
115 flags |= OBJ_SET_XX;
116 } else if ((a[0] == 'e' || a[0] == 'E') &&
117 (a[1] == 'x' || a[1] == 'X') && a[2] == '\0' &&
118 !(flags & OBJ_SET_PX) && next)
119 {
120 flags |= OBJ_SET_EX;
121 unit = UNIT_SECONDS;
122 expire = next;
123 j++;
124 } else if ((a[0] == 'p' || a[0] == 'P') &&
125 (a[1] == 'x' || a[1] == 'X') && a[2] == '\0' &&
126 !(flags & OBJ_SET_EX) && next)
127 {
128 flags |= OBJ_SET_PX;
129 unit = UNIT_MILLISECONDS;
130 expire = next;
131 j++;
132 } else {
133 addReply(c,shared.syntaxerr);
134 return;
135 }
136 }
137
138 c->argv[2] = tryObjectEncoding(c->argv[2]);
139 setGenericCommand(c,flags,c->argv[1],c->argv[2],expire,unit,NULL,NULL);
140 }
141
setnxCommand(client * c)142 void setnxCommand(client *c) {
143 c->argv[2] = tryObjectEncoding(c->argv[2]);
144 setGenericCommand(c,OBJ_SET_NX,c->argv[1],c->argv[2],NULL,0,shared.cone,shared.czero);
145 }
146
setexCommand(client * c)147 void setexCommand(client *c) {
148 c->argv[3] = tryObjectEncoding(c->argv[3]);
149 setGenericCommand(c,OBJ_SET_NO_FLAGS,c->argv[1],c->argv[3],c->argv[2],UNIT_SECONDS,NULL,NULL);
150 }
151
psetexCommand(client * c)152 void psetexCommand(client *c) {
153 c->argv[3] = tryObjectEncoding(c->argv[3]);
154 setGenericCommand(c,OBJ_SET_NO_FLAGS,c->argv[1],c->argv[3],c->argv[2],UNIT_MILLISECONDS,NULL,NULL);
155 }
156
getGenericCommand(client * c)157 int getGenericCommand(client *c) {
158 robj *o;
159
160 if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.nullbulk)) == NULL)
161 return C_OK;
162
163 if (o->type != OBJ_STRING) {
164 addReply(c,shared.wrongtypeerr);
165 return C_ERR;
166 } else {
167 addReplyBulk(c,o);
168 return C_OK;
169 }
170 }
171
getCommand(client * c)172 void getCommand(client *c) {
173 getGenericCommand(c);
174 }
175
getsetCommand(client * c)176 void getsetCommand(client *c) {
177 if (getGenericCommand(c) == C_ERR) return;
178 c->argv[2] = tryObjectEncoding(c->argv[2]);
179 setKey(c->db,c->argv[1],c->argv[2]);
180 notifyKeyspaceEvent(NOTIFY_STRING,"set",c->argv[1],c->db->id);
181 server.dirty++;
182 }
183
setrangeCommand(client * c)184 void setrangeCommand(client *c) {
185 robj *o;
186 long offset;
187 sds value = c->argv[3]->ptr;
188
189 if (getLongFromObjectOrReply(c,c->argv[2],&offset,NULL) != C_OK)
190 return;
191
192 if (offset < 0) {
193 addReplyError(c,"offset is out of range");
194 return;
195 }
196
197 o = lookupKeyWrite(c->db,c->argv[1]);
198 if (o == NULL) {
199 /* Return 0 when setting nothing on a non-existing string */
200 if (sdslen(value) == 0) {
201 addReply(c,shared.czero);
202 return;
203 }
204
205 /* Return when the resulting string exceeds allowed size */
206 if (checkStringLength(c,offset+sdslen(value)) != C_OK)
207 return;
208
209 o = createObject(OBJ_STRING,sdsnewlen(NULL, offset+sdslen(value)));
210 dbAdd(c->db,c->argv[1],o);
211 } else {
212 size_t olen;
213
214 /* Key exists, check type */
215 if (checkType(c,o,OBJ_STRING))
216 return;
217
218 /* Return existing string length when setting nothing */
219 olen = stringObjectLen(o);
220 if (sdslen(value) == 0) {
221 addReplyLongLong(c,olen);
222 return;
223 }
224
225 /* Return when the resulting string exceeds allowed size */
226 if (checkStringLength(c,offset+sdslen(value)) != C_OK)
227 return;
228
229 /* Create a copy when the object is shared or encoded. */
230 o = dbUnshareStringValue(c->db,c->argv[1],o);
231 }
232
233 if (sdslen(value) > 0) {
234 o->ptr = sdsgrowzero(o->ptr,offset+sdslen(value));
235 memcpy((char*)o->ptr+offset,value,sdslen(value));
236 signalModifiedKey(c->db,c->argv[1]);
237 notifyKeyspaceEvent(NOTIFY_STRING,
238 "setrange",c->argv[1],c->db->id);
239 server.dirty++;
240 }
241 addReplyLongLong(c,sdslen(o->ptr));
242 }
243
getrangeCommand(client * c)244 void getrangeCommand(client *c) {
245 robj *o;
246 long long start, end;
247 char *str, llbuf[32];
248 size_t strlen;
249
250 if (getLongLongFromObjectOrReply(c,c->argv[2],&start,NULL) != C_OK)
251 return;
252 if (getLongLongFromObjectOrReply(c,c->argv[3],&end,NULL) != C_OK)
253 return;
254 if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.emptybulk)) == NULL ||
255 checkType(c,o,OBJ_STRING)) return;
256
257 if (o->encoding == OBJ_ENCODING_INT) {
258 str = llbuf;
259 strlen = ll2string(llbuf,sizeof(llbuf),(long)o->ptr);
260 } else {
261 str = o->ptr;
262 strlen = sdslen(str);
263 }
264
265 /* Convert negative indexes */
266 if (start < 0 && end < 0 && start > end) {
267 addReply(c,shared.emptybulk);
268 return;
269 }
270 if (start < 0) start = strlen+start;
271 if (end < 0) end = strlen+end;
272 if (start < 0) start = 0;
273 if (end < 0) end = 0;
274 if ((unsigned long long)end >= strlen) end = strlen-1;
275
276 /* Precondition: end >= 0 && end < strlen, so the only condition where
277 * nothing can be returned is: start > end. */
278 if (start > end || strlen == 0) {
279 addReply(c,shared.emptybulk);
280 } else {
281 addReplyBulkCBuffer(c,(char*)str+start,end-start+1);
282 }
283 }
284
mgetCommand(client * c)285 void mgetCommand(client *c) {
286 int j;
287
288 addReplyMultiBulkLen(c,c->argc-1);
289 for (j = 1; j < c->argc; j++) {
290 robj *o = lookupKeyRead(c->db,c->argv[j]);
291 if (o == NULL) {
292 addReply(c,shared.nullbulk);
293 } else {
294 if (o->type != OBJ_STRING) {
295 addReply(c,shared.nullbulk);
296 } else {
297 addReplyBulk(c,o);
298 }
299 }
300 }
301 }
302
msetGenericCommand(client * c,int nx)303 void msetGenericCommand(client *c, int nx) {
304 int j, busykeys = 0;
305
306 if ((c->argc % 2) == 0) {
307 addReplyError(c,"wrong number of arguments for MSET");
308 return;
309 }
310 /* Handle the NX flag. The MSETNX semantic is to return zero and don't
311 * set nothing at all if at least one already key exists. */
312 if (nx) {
313 for (j = 1; j < c->argc; j += 2) {
314 if (lookupKeyWrite(c->db,c->argv[j]) != NULL) {
315 busykeys++;
316 }
317 }
318 if (busykeys) {
319 addReply(c, shared.czero);
320 return;
321 }
322 }
323
324 for (j = 1; j < c->argc; j += 2) {
325 c->argv[j+1] = tryObjectEncoding(c->argv[j+1]);
326 setKey(c->db,c->argv[j],c->argv[j+1]);
327 notifyKeyspaceEvent(NOTIFY_STRING,"set",c->argv[j],c->db->id);
328 }
329 server.dirty += (c->argc-1)/2;
330 addReply(c, nx ? shared.cone : shared.ok);
331 }
332
msetCommand(client * c)333 void msetCommand(client *c) {
334 msetGenericCommand(c,0);
335 }
336
msetnxCommand(client * c)337 void msetnxCommand(client *c) {
338 msetGenericCommand(c,1);
339 }
340
incrDecrCommand(client * c,long long incr)341 void incrDecrCommand(client *c, long long incr) {
342 long long value, oldvalue;
343 robj *o, *new;
344
345 o = lookupKeyWrite(c->db,c->argv[1]);
346 if (o != NULL && checkType(c,o,OBJ_STRING)) return;
347 if (getLongLongFromObjectOrReply(c,o,&value,NULL) != C_OK) return;
348
349 oldvalue = value;
350 if ((incr < 0 && oldvalue < 0 && incr < (LLONG_MIN-oldvalue)) ||
351 (incr > 0 && oldvalue > 0 && incr > (LLONG_MAX-oldvalue))) {
352 addReplyError(c,"increment or decrement would overflow");
353 return;
354 }
355 value += incr;
356
357 if (o && o->refcount == 1 && o->encoding == OBJ_ENCODING_INT &&
358 (value < 0 || value >= OBJ_SHARED_INTEGERS) &&
359 value >= LONG_MIN && value <= LONG_MAX)
360 {
361 new = o;
362 o->ptr = (void*)((long)value);
363 } else {
364 new = createStringObjectFromLongLong(value);
365 if (o) {
366 dbOverwrite(c->db,c->argv[1],new);
367 } else {
368 dbAdd(c->db,c->argv[1],new);
369 }
370 }
371 signalModifiedKey(c->db,c->argv[1]);
372 notifyKeyspaceEvent(NOTIFY_STRING,"incrby",c->argv[1],c->db->id);
373 server.dirty++;
374 addReply(c,shared.colon);
375 addReply(c,new);
376 addReply(c,shared.crlf);
377 }
378
incrCommand(client * c)379 void incrCommand(client *c) {
380 incrDecrCommand(c,1);
381 }
382
decrCommand(client * c)383 void decrCommand(client *c) {
384 incrDecrCommand(c,-1);
385 }
386
incrbyCommand(client * c)387 void incrbyCommand(client *c) {
388 long long incr;
389
390 if (getLongLongFromObjectOrReply(c, c->argv[2], &incr, NULL) != C_OK) return;
391 incrDecrCommand(c,incr);
392 }
393
decrbyCommand(client * c)394 void decrbyCommand(client *c) {
395 long long incr;
396
397 if (getLongLongFromObjectOrReply(c, c->argv[2], &incr, NULL) != C_OK) return;
398 incrDecrCommand(c,-incr);
399 }
400
incrbyfloatCommand(client * c)401 void incrbyfloatCommand(client *c) {
402 long double incr, value;
403 robj *o, *new, *aux;
404
405 o = lookupKeyWrite(c->db,c->argv[1]);
406 if (o != NULL && checkType(c,o,OBJ_STRING)) return;
407 if (getLongDoubleFromObjectOrReply(c,o,&value,NULL) != C_OK ||
408 getLongDoubleFromObjectOrReply(c,c->argv[2],&incr,NULL) != C_OK)
409 return;
410
411 value += incr;
412 if (isnan(value) || isinf(value)) {
413 addReplyError(c,"increment would produce NaN or Infinity");
414 return;
415 }
416 new = createStringObjectFromLongDouble(value,1);
417 if (o)
418 dbOverwrite(c->db,c->argv[1],new);
419 else
420 dbAdd(c->db,c->argv[1],new);
421 signalModifiedKey(c->db,c->argv[1]);
422 notifyKeyspaceEvent(NOTIFY_STRING,"incrbyfloat",c->argv[1],c->db->id);
423 server.dirty++;
424 addReplyBulk(c,new);
425
426 /* Always replicate INCRBYFLOAT as a SET command with the final value
427 * in order to make sure that differences in float precision or formatting
428 * will not create differences in replicas or after an AOF restart. */
429 aux = createStringObject("SET",3);
430 rewriteClientCommandArgument(c,0,aux);
431 decrRefCount(aux);
432 rewriteClientCommandArgument(c,2,new);
433 }
434
appendCommand(client * c)435 void appendCommand(client *c) {
436 size_t totlen;
437 robj *o, *append;
438
439 o = lookupKeyWrite(c->db,c->argv[1]);
440 if (o == NULL) {
441 /* Create the key */
442 c->argv[2] = tryObjectEncoding(c->argv[2]);
443 dbAdd(c->db,c->argv[1],c->argv[2]);
444 incrRefCount(c->argv[2]);
445 totlen = stringObjectLen(c->argv[2]);
446 } else {
447 /* Key exists, check type */
448 if (checkType(c,o,OBJ_STRING))
449 return;
450
451 /* "append" is an argument, so always an sds */
452 append = c->argv[2];
453 totlen = stringObjectLen(o)+sdslen(append->ptr);
454 if (checkStringLength(c,totlen) != C_OK)
455 return;
456
457 /* Append the value */
458 o = dbUnshareStringValue(c->db,c->argv[1],o);
459 o->ptr = sdscatlen(o->ptr,append->ptr,sdslen(append->ptr));
460 totlen = sdslen(o->ptr);
461 }
462 signalModifiedKey(c->db,c->argv[1]);
463 notifyKeyspaceEvent(NOTIFY_STRING,"append",c->argv[1],c->db->id);
464 server.dirty++;
465 addReplyLongLong(c,totlen);
466 }
467
strlenCommand(client * c)468 void strlenCommand(client *c) {
469 robj *o;
470 if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.czero)) == NULL ||
471 checkType(c,o,OBJ_STRING)) return;
472 addReplyLongLong(c,stringObjectLen(o));
473 }
474