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,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;
305
306 if ((c->argc % 2) == 0) {
307 addReplyError(c,"wrong number of arguments for MSET");
308 return;
309 }
310
311 /* Handle the NX flag. The MSETNX semantic is to return zero and don't
312 * set anything if at least one key alerady exists. */
313 if (nx) {
314 for (j = 1; j < c->argc; j += 2) {
315 if (lookupKeyWrite(c->db,c->argv[j]) != NULL) {
316 addReply(c, shared.czero);
317 return;
318 }
319 }
320 }
321
322 for (j = 1; j < c->argc; j += 2) {
323 c->argv[j+1] = tryObjectEncoding(c->argv[j+1]);
324 setKey(c->db,c->argv[j],c->argv[j+1]);
325 notifyKeyspaceEvent(NOTIFY_STRING,"set",c->argv[j],c->db->id);
326 }
327 server.dirty += (c->argc-1)/2;
328 addReply(c, nx ? shared.cone : shared.ok);
329 }
330
msetCommand(client * c)331 void msetCommand(client *c) {
332 msetGenericCommand(c,0);
333 }
334
msetnxCommand(client * c)335 void msetnxCommand(client *c) {
336 msetGenericCommand(c,1);
337 }
338
incrDecrCommand(client * c,long long incr)339 void incrDecrCommand(client *c, long long incr) {
340 long long value, oldvalue;
341 robj *o, *new;
342
343 o = lookupKeyWrite(c->db,c->argv[1]);
344 if (o != NULL && checkType(c,o,OBJ_STRING)) return;
345 if (getLongLongFromObjectOrReply(c,o,&value,NULL) != C_OK) return;
346
347 oldvalue = value;
348 if ((incr < 0 && oldvalue < 0 && incr < (LLONG_MIN-oldvalue)) ||
349 (incr > 0 && oldvalue > 0 && incr > (LLONG_MAX-oldvalue))) {
350 addReplyError(c,"increment or decrement would overflow");
351 return;
352 }
353 value += incr;
354
355 if (o && o->refcount == 1 && o->encoding == OBJ_ENCODING_INT &&
356 (value < 0 || value >= OBJ_SHARED_INTEGERS) &&
357 value >= LONG_MIN && value <= LONG_MAX)
358 {
359 new = o;
360 o->ptr = (void*)((long)value);
361 } else {
362 new = createStringObjectFromLongLongForValue(value);
363 if (o) {
364 dbOverwrite(c->db,c->argv[1],new);
365 } else {
366 dbAdd(c->db,c->argv[1],new);
367 }
368 }
369 signalModifiedKey(c->db,c->argv[1]);
370 notifyKeyspaceEvent(NOTIFY_STRING,"incrby",c->argv[1],c->db->id);
371 server.dirty++;
372 addReply(c,shared.colon);
373 addReply(c,new);
374 addReply(c,shared.crlf);
375 }
376
incrCommand(client * c)377 void incrCommand(client *c) {
378 incrDecrCommand(c,1);
379 }
380
decrCommand(client * c)381 void decrCommand(client *c) {
382 incrDecrCommand(c,-1);
383 }
384
incrbyCommand(client * c)385 void incrbyCommand(client *c) {
386 long long incr;
387
388 if (getLongLongFromObjectOrReply(c, c->argv[2], &incr, NULL) != C_OK) return;
389 incrDecrCommand(c,incr);
390 }
391
decrbyCommand(client * c)392 void decrbyCommand(client *c) {
393 long long incr;
394
395 if (getLongLongFromObjectOrReply(c, c->argv[2], &incr, NULL) != C_OK) return;
396 incrDecrCommand(c,-incr);
397 }
398
incrbyfloatCommand(client * c)399 void incrbyfloatCommand(client *c) {
400 long double incr, value;
401 robj *o, *new, *aux;
402
403 o = lookupKeyWrite(c->db,c->argv[1]);
404 if (o != NULL && checkType(c,o,OBJ_STRING)) return;
405 if (getLongDoubleFromObjectOrReply(c,o,&value,NULL) != C_OK ||
406 getLongDoubleFromObjectOrReply(c,c->argv[2],&incr,NULL) != C_OK)
407 return;
408
409 value += incr;
410 if (isnan(value) || isinf(value)) {
411 addReplyError(c,"increment would produce NaN or Infinity");
412 return;
413 }
414 new = createStringObjectFromLongDouble(value,1);
415 if (o)
416 dbOverwrite(c->db,c->argv[1],new);
417 else
418 dbAdd(c->db,c->argv[1],new);
419 signalModifiedKey(c->db,c->argv[1]);
420 notifyKeyspaceEvent(NOTIFY_STRING,"incrbyfloat",c->argv[1],c->db->id);
421 server.dirty++;
422 addReplyBulk(c,new);
423
424 /* Always replicate INCRBYFLOAT as a SET command with the final value
425 * in order to make sure that differences in float precision or formatting
426 * will not create differences in replicas or after an AOF restart. */
427 aux = createStringObject("SET",3);
428 rewriteClientCommandArgument(c,0,aux);
429 decrRefCount(aux);
430 rewriteClientCommandArgument(c,2,new);
431 }
432
appendCommand(client * c)433 void appendCommand(client *c) {
434 size_t totlen;
435 robj *o, *append;
436
437 o = lookupKeyWrite(c->db,c->argv[1]);
438 if (o == NULL) {
439 /* Create the key */
440 c->argv[2] = tryObjectEncoding(c->argv[2]);
441 dbAdd(c->db,c->argv[1],c->argv[2]);
442 incrRefCount(c->argv[2]);
443 totlen = stringObjectLen(c->argv[2]);
444 } else {
445 /* Key exists, check type */
446 if (checkType(c,o,OBJ_STRING))
447 return;
448
449 /* "append" is an argument, so always an sds */
450 append = c->argv[2];
451 totlen = stringObjectLen(o)+sdslen(append->ptr);
452 if (checkStringLength(c,totlen) != C_OK)
453 return;
454
455 /* Append the value */
456 o = dbUnshareStringValue(c->db,c->argv[1],o);
457 o->ptr = sdscatlen(o->ptr,append->ptr,sdslen(append->ptr));
458 totlen = sdslen(o->ptr);
459 }
460 signalModifiedKey(c->db,c->argv[1]);
461 notifyKeyspaceEvent(NOTIFY_STRING,"append",c->argv[1],c->db->id);
462 server.dirty++;
463 addReplyLongLong(c,totlen);
464 }
465
strlenCommand(client * c)466 void strlenCommand(client *c) {
467 robj *o;
468 if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.czero)) == NULL ||
469 checkType(c,o,OBJ_STRING)) return;
470 addReplyLongLong(c,stringObjectLen(o));
471 }
472