X-Git-Url: https://git.saurik.com/redis.git/blobdiff_plain/7ecd4644e7fe48309d4b8445ec62c7fe8c0443ff..c66bf1fa32655ccf3f39b4cd72953459576463f5:/src/t_string.c

diff --git a/src/t_string.c b/src/t_string.c
index d537c8b9..64b6f0c5 100644
--- a/src/t_string.c
+++ b/src/t_string.c
@@ -1,10 +1,17 @@
-#include <limits.h>
 #include "redis.h"
 
 /*-----------------------------------------------------------------------------
  * String Commands
  *----------------------------------------------------------------------------*/
 
+static int checkStringLength(redisClient *c, long long size) {
+    if (size > 512*1024*1024) {
+        addReplyError(c,"string exceeds maximum allowed size (512MB)");
+        return REDIS_ERR;
+    }
+    return REDIS_OK;
+}
+
 void setGenericCommand(redisClient *c, int nx, robj *key, robj *val, robj *expire) {
     int retval;
     long seconds = 0; /* initialized to avoid an harmness warning */
@@ -30,7 +37,7 @@ void setGenericCommand(redisClient *c, int nx, robj *key, robj *val, robj *expir
     } else {
         incrRefCount(val);
     }
-    touchWatchedKey(c->db,key);
+    signalModifiedKey(c->db,key);
     server.dirty++;
     removeExpire(c->db,key);
     if (expire) setExpire(c->db,key,time(NULL)+seconds);
@@ -76,7 +83,7 @@ void getsetCommand(redisClient *c) {
     c->argv[2] = tryObjectEncoding(c->argv[2]);
     dbReplace(c->db,c->argv[1],c->argv[2]);
     incrRefCount(c->argv[2]);
-    touchWatchedKey(c->db,c->argv[1]);
+    signalModifiedKey(c->db,c->argv[1]);
     server.dirty++;
     removeExpire(c->db,c->argv[1]);
 }
@@ -88,10 +95,8 @@ static int getBitOffsetFromArgument(redisClient *c, robj *o, size_t *offset) {
     if (getLongLongFromObjectOrReply(c,o,&loffset,err) != REDIS_OK)
         return REDIS_ERR;
 
-    /* Limit offset to SIZE_T_MAX or 512MB in bytes */
-    if ((loffset < 0) ||
-        ((unsigned long long)loffset >= (unsigned)SIZE_T_MAX) ||
-        ((unsigned long long)loffset >> 3) >= (512*1024*1024))
+    /* Limit offset to 512MB in bytes */
+    if ((loffset < 0) || ((unsigned long long)loffset >> 3) >= (512*1024*1024))
     {
         addReplyError(c,err);
         return REDIS_ERR;
@@ -105,17 +110,18 @@ void setbitCommand(redisClient *c) {
     robj *o;
     char *err = "bit is not an integer or out of range";
     size_t bitoffset;
-    long long bitvalue;
-    int byte, bit, on;
+    int byte, bit;
+    int byteval, bitval;
+    long on;
 
     if (getBitOffsetFromArgument(c,c->argv[2],&bitoffset) != REDIS_OK)
         return;
 
-    if (getLongLongFromObjectOrReply(c,c->argv[3],&bitvalue,err) != REDIS_OK)
+    if (getLongFromObjectOrReply(c,c->argv[3],&on,err) != REDIS_OK)
         return;
 
-    /* A bit can only be set to be on or off... */
-    if (bitvalue & ~1) {
+    /* Bits can only be set or cleared... */
+    if (on & ~1) {
         addReplyError(c,err);
         return;
     }
@@ -136,23 +142,30 @@ void setbitCommand(redisClient *c) {
         }
     }
 
+    /* Grow sds value to the right length if necessary */
     byte = bitoffset >> 3;
-    bit = 7 - (bitoffset & 0x7);
-    on = bitvalue & 0x1;
     o->ptr = sdsgrowzero(o->ptr,byte+1);
-    ((char*)o->ptr)[byte] |= on << bit;
-    ((char*)o->ptr)[byte] &= ~((!on) << bit);
 
-    touchWatchedKey(c->db,c->argv[1]);
+    /* Get current values */
+    byteval = ((char*)o->ptr)[byte];
+    bit = 7 - (bitoffset & 0x7);
+    bitval = byteval & (1 << bit);
+
+    /* Update byte with new bit value and return original value */
+    byteval &= ~(1 << bit);
+    byteval |= ((on & 0x1) << bit);
+    ((char*)o->ptr)[byte] = byteval;
+    signalModifiedKey(c->db,c->argv[1]);
     server.dirty++;
-    addReply(c,shared.cone);
+    addReply(c, bitval ? shared.cone : shared.czero);
 }
 
 void getbitCommand(redisClient *c) {
     robj *o;
-    size_t bitoffset, byte, bitmask;
-    int on = 0;
     char llbuf[32];
+    size_t bitoffset;
+    size_t byte, bit;
+    size_t bitval = 0;
 
     if (getBitOffsetFromArgument(c,c->argv[2],&bitoffset) != REDIS_OK)
         return;
@@ -161,15 +174,116 @@ void getbitCommand(redisClient *c) {
         checkType(c,o,REDIS_STRING)) return;
 
     byte = bitoffset >> 3;
-    bitmask = 1 << (7 - (bitoffset & 0x7));
+    bit = 7 - (bitoffset & 0x7);
     if (o->encoding != REDIS_ENCODING_RAW) {
         if (byte < (size_t)ll2string(llbuf,sizeof(llbuf),(long)o->ptr))
-            on = llbuf[byte] & bitmask;
+            bitval = llbuf[byte] & (1 << bit);
     } else {
         if (byte < sdslen(o->ptr))
-            on = ((sds)o->ptr)[byte] & bitmask;
+            bitval = ((char*)o->ptr)[byte] & (1 << bit);
+    }
+
+    addReply(c, bitval ? shared.cone : shared.czero);
+}
+
+void setrangeCommand(redisClient *c) {
+    robj *o;
+    long offset;
+    sds value = c->argv[3]->ptr;
+
+    if (getLongFromObjectOrReply(c,c->argv[2],&offset,NULL) != REDIS_OK)
+        return;
+
+    if (offset < 0) {
+        addReplyError(c,"offset is out of range");
+        return;
+    }
+
+    o = lookupKeyWrite(c->db,c->argv[1]);
+    if (o == NULL) {
+        /* Return 0 when setting nothing on a non-existing string */
+        if (sdslen(value) == 0) {
+            addReply(c,shared.czero);
+            return;
+        }
+
+        /* Return when the resulting string exceeds allowed size */
+        if (checkStringLength(c,offset+sdslen(value)) != REDIS_OK)
+            return;
+
+        o = createObject(REDIS_STRING,sdsempty());
+        dbAdd(c->db,c->argv[1],o);
+    } else {
+        size_t olen;
+
+        /* Key exists, check type */
+        if (checkType(c,o,REDIS_STRING))
+            return;
+
+        /* Return existing string length when setting nothing */
+        olen = stringObjectLen(o);
+        if (sdslen(value) == 0) {
+            addReplyLongLong(c,olen);
+            return;
+        }
+
+        /* Return when the resulting string exceeds allowed size */
+        if (checkStringLength(c,offset+sdslen(value)) != REDIS_OK)
+            return;
+
+        /* Create a copy when the object is shared or encoded. */
+        if (o->refcount != 1 || o->encoding != REDIS_ENCODING_RAW) {
+            robj *decoded = getDecodedObject(o);
+            o = createStringObject(decoded->ptr, sdslen(decoded->ptr));
+            decrRefCount(decoded);
+            dbReplace(c->db,c->argv[1],o);
+        }
+    }
+
+    if (sdslen(value) > 0) {
+        o->ptr = sdsgrowzero(o->ptr,offset+sdslen(value));
+        memcpy((char*)o->ptr+offset,value,sdslen(value));
+        signalModifiedKey(c->db,c->argv[1]);
+        server.dirty++;
+    }
+    addReplyLongLong(c,sdslen(o->ptr));
+}
+
+void getrangeCommand(redisClient *c) {
+    robj *o;
+    long start, end;
+    char *str, llbuf[32];
+    size_t strlen;
+
+    if (getLongFromObjectOrReply(c,c->argv[2],&start,NULL) != REDIS_OK)
+        return;
+    if (getLongFromObjectOrReply(c,c->argv[3],&end,NULL) != REDIS_OK)
+        return;
+    if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.emptybulk)) == NULL ||
+        checkType(c,o,REDIS_STRING)) return;
+
+    if (o->encoding == REDIS_ENCODING_INT) {
+        str = llbuf;
+        strlen = ll2string(llbuf,sizeof(llbuf),(long)o->ptr);
+    } else {
+        str = o->ptr;
+        strlen = sdslen(str);
+    }
+
+    /* Convert negative indexes */
+    if (start < 0) start = strlen+start;
+    if (end < 0) end = strlen+end;
+    if (start < 0) start = 0;
+    if (end < 0) end = 0;
+    if ((unsigned)end >= strlen) end = strlen-1;
+
+    /* Precondition: end >= 0 && end < strlen, so the only condition where
+     * nothing can be returned is: start > end. */
+    if (start > end) {
+        addReply(c,shared.emptybulk);
+    } else {
+        addReplyBulkCBuffer(c,(char*)str+start,end-start+1);
     }
-    addReply(c, on ? shared.cone : shared.czero);
 }
 
 void mgetCommand(redisClient *c) {
@@ -216,7 +330,7 @@ void msetGenericCommand(redisClient *c, int nx) {
         dbReplace(c->db,c->argv[j],c->argv[j+1]);
         incrRefCount(c->argv[j+1]);
         removeExpire(c->db,c->argv[j]);
-        touchWatchedKey(c->db,c->argv[j]);
+        signalModifiedKey(c->db,c->argv[j]);
     }
     server.dirty += (c->argc-1)/2;
     addReply(c, nx ? shared.cone : shared.ok);
@@ -231,17 +345,22 @@ void msetnxCommand(redisClient *c) {
 }
 
 void incrDecrCommand(redisClient *c, long long incr) {
-    long long value;
+    long long value, oldvalue;
     robj *o;
 
     o = lookupKeyWrite(c->db,c->argv[1]);
     if (o != NULL && checkType(c,o,REDIS_STRING)) return;
     if (getLongLongFromObjectOrReply(c,o,&value,NULL) != REDIS_OK) return;
 
+    oldvalue = value;
     value += incr;
+    if ((incr < 0 && value > oldvalue) || (incr > 0 && value < oldvalue)) {
+        addReplyError(c,"increment or decrement would overflow");
+        return;
+    }
     o = createStringObjectFromLongLong(value);
     dbReplace(c->db,c->argv[1],o);
-    touchWatchedKey(c->db,c->argv[1]);
+    signalModifiedKey(c->db,c->argv[1]);
     server.dirty++;
     addReply(c,shared.colon);
     addReply(c,o);
@@ -271,31 +390,26 @@ void decrbyCommand(redisClient *c) {
 }
 
 void appendCommand(redisClient *c) {
-    int retval;
     size_t totlen;
     robj *o, *append;
 
     o = lookupKeyWrite(c->db,c->argv[1]);
-    c->argv[2] = tryObjectEncoding(c->argv[2]);
     if (o == NULL) {
         /* Create the key */
-        retval = dbAdd(c->db,c->argv[1],c->argv[2]);
+        c->argv[2] = tryObjectEncoding(c->argv[2]);
+        dbAdd(c->db,c->argv[1],c->argv[2]);
         incrRefCount(c->argv[2]);
         totlen = stringObjectLen(c->argv[2]);
     } else {
-        if (o->type != REDIS_STRING) {
-            addReply(c,shared.wrongtypeerr);
+        /* Key exists, check type */
+        if (checkType(c,o,REDIS_STRING))
             return;
-        }
 
-        append = getDecodedObject(c->argv[2]);
-        if (o->encoding == REDIS_ENCODING_RAW &&
-            (sdslen(o->ptr) + sdslen(append->ptr)) > 512*1024*1024)
-        {
-            addReplyError(c,"string exceeds maximum allowed size (512MB)");
-            decrRefCount(append);
+        /* "append" is an argument, so always an sds */
+        append = c->argv[2];
+        totlen = stringObjectLen(o)+sdslen(append->ptr);
+        if (checkStringLength(c,totlen) != REDIS_OK)
             return;
-        }
 
         /* If the object is shared or encoded, we have to make a copy */
         if (o->refcount != 1 || o->encoding != REDIS_ENCODING_RAW) {
@@ -307,65 +421,17 @@ void appendCommand(redisClient *c) {
 
         /* Append the value */
         o->ptr = sdscatlen(o->ptr,append->ptr,sdslen(append->ptr));
-        decrRefCount(append);
         totlen = sdslen(o->ptr);
     }
-    touchWatchedKey(c->db,c->argv[1]);
+    signalModifiedKey(c->db,c->argv[1]);
     server.dirty++;
     addReplyLongLong(c,totlen);
 }
 
-void substrCommand(redisClient *c) {
-    robj *o;
-    long start = atoi(c->argv[2]->ptr);
-    long end = atoi(c->argv[3]->ptr);
-    size_t rangelen, strlen;
-    sds range;
-
-    if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.nullbulk)) == NULL ||
-        checkType(c,o,REDIS_STRING)) return;
-
-    o = getDecodedObject(o);
-    strlen = sdslen(o->ptr);
-
-    /* convert negative indexes */
-    if (start < 0) start = strlen+start;
-    if (end < 0) end = strlen+end;
-    if (start < 0) start = 0;
-    if (end < 0) end = 0;
-
-    /* indexes sanity checks */
-    if (start > end || (size_t)start >= strlen) {
-        /* Out of range start or start > end result in null reply */
-        addReply(c,shared.nullbulk);
-        decrRefCount(o);
-        return;
-    }
-    if ((size_t)end >= strlen) end = strlen-1;
-    rangelen = (end-start)+1;
-
-    /* Return the result */
-    addReplySds(c,sdscatprintf(sdsempty(),"$%zu\r\n",rangelen));
-    range = sdsnewlen((char*)o->ptr+start,rangelen);
-    addReplySds(c,range);
-    addReply(c,shared.crlf);
-    decrRefCount(o);
-}
-
 void strlenCommand(redisClient *c) {
     robj *o;
-
     if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.czero)) == NULL ||
         checkType(c,o,REDIS_STRING)) return;
-
-    if (o->encoding == REDIS_ENCODING_RAW) {
-        addReplyLongLong(c,sdslen(o->ptr));
-    } else if (o->encoding == REDIS_ENCODING_INT) {
-        char llbuf[32];
-        int len = ll2string(llbuf,sizeof(llbuf),(long)o->ptr);
-        addReplyLongLong(c,len);
-    } else {
-        redisPanic("Unknown string encoding");
-    }
+    addReplyLongLong(c,stringObjectLen(o));
 }