From 221782ccc69b4c56608942f3fe9e47773a32866e Mon Sep 17 00:00:00 2001 From: Pieter Noordhuis Date: Fri, 13 May 2011 23:24:19 +0200 Subject: [PATCH] Move rdbLoad* to top; update comments --- src/rdb.c | 399 ++++++++++++++++++++++++++-------------------------- src/rdb.h | 41 +++++- src/redis.h | 27 ---- 3 files changed, 233 insertions(+), 234 deletions(-) diff --git a/src/rdb.c b/src/rdb.c index fdb04754..ee992809 100644 --- a/src/rdb.c +++ b/src/rdb.c @@ -18,12 +18,26 @@ int rdbSaveType(rio *rdb, unsigned char type) { return rdbWriteRaw(rdb,&type,1); } +int rdbLoadType(rio *rdb) { + unsigned char type; + if (rioRead(rdb,&type,1) == 0) return -1; + return type; +} + int rdbSaveTime(rio *rdb, time_t t) { int32_t t32 = (int32_t) t; return rdbWriteRaw(rdb,&t32,4); } -/* check rdbLoadLen() comments for more info */ +time_t rdbLoadTime(rio *rdb) { + int32_t t32; + if (rioRead(rdb,&t32,4) == 0) return -1; + return (time_t)t32; +} + +/* Saves an encoded length. The first two bits in the first byte are used to + * hold the encoding type. See the REDIS_RDB_* definitions for more information + * on the types of encoding. */ int rdbSaveLen(rio *rdb, uint32_t len) { unsigned char buf[2]; size_t nwritten; @@ -50,13 +64,40 @@ int rdbSaveLen(rio *rdb, uint32_t len) { return nwritten; } -/* Encode 'value' as an integer if possible (if integer will fit the - * supported range). If the function sucessful encoded the integer - * then the (up to 5 bytes) encoded representation is written in the - * string pointed by 'enc' and the length is returned. Otherwise - * 0 is returned. */ +/* Load an encoded length. The "isencoded" argument is set to 1 if the length + * is not actually a length but an "encoding type". See the REDIS_RDB_ENC_* + * definitions in rdb.h for more information. */ +uint32_t rdbLoadLen(rio *rdb, int *isencoded) { + unsigned char buf[2]; + uint32_t len; + int type; + + if (isencoded) *isencoded = 0; + if (rioRead(rdb,buf,1) == 0) return REDIS_RDB_LENERR; + type = (buf[0]&0xC0)>>6; + if (type == REDIS_RDB_ENCVAL) { + /* Read a 6 bit encoding type. */ + if (isencoded) *isencoded = 1; + return buf[0]&0x3F; + } else if (type == REDIS_RDB_6BITLEN) { + /* Read a 6 bit len. */ + return buf[0]&0x3F; + } else if (type == REDIS_RDB_14BITLEN) { + /* Read a 14 bit len. */ + if (rioRead(rdb,buf+1,1) == 0) return REDIS_RDB_LENERR; + return ((buf[0]&0x3F)<<8)|buf[1]; + } else { + /* Read a 32 bit len. */ + if (rioRead(rdb,&len,4) == 0) return REDIS_RDB_LENERR; + return ntohl(len); + } +} + +/* Encodes the "value" argument as integer when it fits in the supported ranges + * for encoded types. If the function successfully encodes the integer, the + * representation is stored in the buffer pointer to by "enc" and the string + * length is returned. Otherwise 0 is returned. */ int rdbEncodeInteger(long long value, unsigned char *enc) { - /* Finally check if it fits in our ranges */ if (value >= -(1<<7) && value <= (1<<7)-1) { enc[0] = (REDIS_RDB_ENCVAL<<6)|REDIS_RDB_ENC_INT8; enc[1] = value&0xFF; @@ -78,6 +119,36 @@ int rdbEncodeInteger(long long value, unsigned char *enc) { } } +/* Loads an integer-encoded object with the specified encoding type "enctype". + * If the "encode" argument is set the function may return an integer-encoded + * string object, otherwise it always returns a raw string object. */ +robj *rdbLoadIntegerObject(rio *rdb, int enctype, int encode) { + unsigned char enc[4]; + long long val; + + if (enctype == REDIS_RDB_ENC_INT8) { + if (rioRead(rdb,enc,1) == 0) return NULL; + val = (signed char)enc[0]; + } else if (enctype == REDIS_RDB_ENC_INT16) { + uint16_t v; + if (rioRead(rdb,enc,2) == 0) return NULL; + v = enc[0]|(enc[1]<<8); + val = (int16_t)v; + } else if (enctype == REDIS_RDB_ENC_INT32) { + uint32_t v; + if (rioRead(rdb,enc,4) == 0) return NULL; + v = enc[0]|(enc[1]<<8)|(enc[2]<<16)|(enc[3]<<24); + val = (int32_t)v; + } else { + val = 0; /* anti-warning */ + redisPanic("Unknown RDB integer encoding type"); + } + if (encode) + return createStringObjectFromLongLong(val); + else + return createObject(REDIS_STRING,sdsfromlonglong(val)); +} + /* String objects in the form "2391" "-100" without any space and with a * range of values that can fit in an 8, 16 or 32 bit signed value can be * encoded as integers to save space */ @@ -134,6 +205,25 @@ writeerr: return -1; } +robj *rdbLoadLzfStringObject(rio *rdb) { + unsigned int len, clen; + unsigned char *c = NULL; + sds val = NULL; + + if ((clen = rdbLoadLen(rdb,NULL)) == REDIS_RDB_LENERR) return NULL; + if ((len = rdbLoadLen(rdb,NULL)) == REDIS_RDB_LENERR) return NULL; + if ((c = zmalloc(clen)) == NULL) goto err; + if ((val = sdsnewlen(NULL,len)) == NULL) goto err; + if (rioRead(rdb,c,clen) == 0) goto err; + if (lzf_decompress(c,clen,val,len) == 0) goto err; + zfree(c); + return createObject(REDIS_STRING,val); +err: + zfree(c); + sdsfree(val); + return NULL; +} + /* Save a string objet as [len][data] on disk. If the object is a string * representation of an integer value we try to save it in a special form */ int rdbSaveRawString(rio *rdb, unsigned char *s, size_t len) { @@ -199,6 +289,42 @@ int rdbSaveStringObject(rio *rdb, robj *obj) { } } +robj *rdbGenericLoadStringObject(rio *rdb, int encode) { + int isencoded; + uint32_t len; + sds val; + + len = rdbLoadLen(rdb,&isencoded); + if (isencoded) { + switch(len) { + case REDIS_RDB_ENC_INT8: + case REDIS_RDB_ENC_INT16: + case REDIS_RDB_ENC_INT32: + return rdbLoadIntegerObject(rdb,len,encode); + case REDIS_RDB_ENC_LZF: + return rdbLoadLzfStringObject(rdb); + default: + redisPanic("Unknown RDB encoding type"); + } + } + + if (len == REDIS_RDB_LENERR) return NULL; + val = sdsnewlen(NULL,len); + if (len && rioRead(rdb,val,len) == 0) { + sdsfree(val); + return NULL; + } + return createObject(REDIS_STRING,val); +} + +robj *rdbLoadStringObject(rio *rdb) { + return rdbGenericLoadStringObject(rdb,0); +} + +robj *rdbLoadEncodedStringObject(rio *rdb) { + return rdbGenericLoadStringObject(rdb,1); +} + /* Save a double value. Doubles are saved as strings prefixed by an unsigned * 8 bit integer specifing the length of the representation. * This 8 bit integer has special values in order to specify the following @@ -241,6 +367,71 @@ int rdbSaveDoubleValue(rio *rdb, double val) { return rdbWriteRaw(rdb,buf,len); } +/* For information about double serialization check rdbSaveDoubleValue() */ +int rdbLoadDoubleValue(rio *rdb, double *val) { + char buf[128]; + unsigned char len; + + if (rioRead(rdb,&len,1) == 0) return -1; + switch(len) { + case 255: *val = R_NegInf; return 0; + case 254: *val = R_PosInf; return 0; + case 253: *val = R_Nan; return 0; + default: + if (rioRead(rdb,buf,len) == 0) return -1; + buf[len] = '\0'; + sscanf(buf, "%lg", val); + return 0; + } +} + +/* Save the object type of object "o". */ +int rdbSaveObjectType(rio *rdb, robj *o) { + switch (o->type) { + case REDIS_STRING: + return rdbSaveType(rdb,REDIS_RDB_TYPE_STRING); + case REDIS_LIST: + if (o->encoding == REDIS_ENCODING_ZIPLIST) + return rdbSaveType(rdb,REDIS_RDB_TYPE_LIST_ZIPLIST); + else if (o->encoding == REDIS_ENCODING_LINKEDLIST) + return rdbSaveType(rdb,REDIS_RDB_TYPE_LIST); + else + redisPanic("Unknown list encoding"); + case REDIS_SET: + if (o->encoding == REDIS_ENCODING_INTSET) + return rdbSaveType(rdb,REDIS_RDB_TYPE_SET_INTSET); + else if (o->encoding == REDIS_ENCODING_HT) + return rdbSaveType(rdb,REDIS_RDB_TYPE_SET); + else + redisPanic("Unknown set encoding"); + case REDIS_ZSET: + if (o->encoding == REDIS_ENCODING_ZIPLIST) + return rdbSaveType(rdb,REDIS_RDB_TYPE_ZSET_ZIPLIST); + else if (o->encoding == REDIS_ENCODING_SKIPLIST) + return rdbSaveType(rdb,REDIS_RDB_TYPE_ZSET); + else + redisPanic("Unknown sorted set encoding"); + case REDIS_HASH: + if (o->encoding == REDIS_ENCODING_ZIPMAP) + return rdbSaveType(rdb,REDIS_RDB_TYPE_HASH_ZIPMAP); + else if (o->encoding == REDIS_ENCODING_HT) + return rdbSaveType(rdb,REDIS_RDB_TYPE_HASH); + else + redisPanic("Unknown hash encoding"); + default: + redisPanic("Unknown object type"); + } + return -1; /* avoid warning */ +} + +/* Load object type. Return -1 when the byte doesn't contain an object type. */ +int rdbLoadObjectType(rio *rdb) { + int type; + if ((type = rdbLoadType(rdb)) == -1) return -1; + if (!rdbIsObjectType(type)) return -1; + return type; +} + /* Save a Redis object. Returns -1 on error, 0 on success. */ int rdbSaveObject(rio *rdb, robj *o) { int n, nwritten = 0; @@ -366,53 +557,6 @@ off_t rdbSavedObjectLen(robj *o) { return len; } -/* Save the object type of object "o". */ -int rdbSaveObjectType(rio *rdb, robj *o) { - switch (o->type) { - case REDIS_STRING: - return rdbSaveType(rdb,REDIS_RDB_TYPE_STRING); - case REDIS_LIST: - if (o->encoding == REDIS_ENCODING_ZIPLIST) - return rdbSaveType(rdb,REDIS_RDB_TYPE_LIST_ZIPLIST); - else if (o->encoding == REDIS_ENCODING_LINKEDLIST) - return rdbSaveType(rdb,REDIS_RDB_TYPE_LIST); - else - redisPanic("Unknown list encoding"); - case REDIS_SET: - if (o->encoding == REDIS_ENCODING_INTSET) - return rdbSaveType(rdb,REDIS_RDB_TYPE_SET_INTSET); - else if (o->encoding == REDIS_ENCODING_HT) - return rdbSaveType(rdb,REDIS_RDB_TYPE_SET); - else - redisPanic("Unknown set encoding"); - case REDIS_ZSET: - if (o->encoding == REDIS_ENCODING_ZIPLIST) - return rdbSaveType(rdb,REDIS_RDB_TYPE_ZSET_ZIPLIST); - else if (o->encoding == REDIS_ENCODING_SKIPLIST) - return rdbSaveType(rdb,REDIS_RDB_TYPE_ZSET); - else - redisPanic("Unknown sorted set encoding"); - case REDIS_HASH: - if (o->encoding == REDIS_ENCODING_ZIPMAP) - return rdbSaveType(rdb,REDIS_RDB_TYPE_HASH_ZIPMAP); - else if (o->encoding == REDIS_ENCODING_HT) - return rdbSaveType(rdb,REDIS_RDB_TYPE_HASH); - else - redisPanic("Unknown hash encoding"); - default: - redisPanic("Unknown object type"); - } - return -1; /* avoid warning */ -} - -/* Load object type. Return -1 when the byte doesn't contain an object type. */ -int rdbLoadObjectType(rio *rdb) { - int type; - if ((type = rdbLoadType(rdb)) == -1) return -1; - if (!rdbIsObjectType(type)) return -1; - return type; -} - /* Save a key-value pair, with expire time, type, key, value. * On error -1 is returned. * On success if the key was actaully saved 1 is returned, otherwise 0 @@ -558,153 +702,6 @@ void rdbRemoveTempFile(pid_t childpid) { unlink(tmpfile); } -int rdbLoadType(rio *rdb) { - unsigned char type; - if (rioRead(rdb,&type,1) == 0) return -1; - return type; -} - -time_t rdbLoadTime(rio *rdb) { - int32_t t32; - if (rioRead(rdb,&t32,4) == 0) return -1; - return (time_t) t32; -} - -/* Load an encoded length from the DB, see the REDIS_RDB_* defines on the top - * of this file for a description of how this are stored on disk. - * - * isencoded is set to 1 if the readed length is not actually a length but - * an "encoding type", check the above comments for more info */ -uint32_t rdbLoadLen(rio *rdb, int *isencoded) { - unsigned char buf[2]; - uint32_t len; - int type; - - if (isencoded) *isencoded = 0; - if (rioRead(rdb,buf,1) == 0) return REDIS_RDB_LENERR; - type = (buf[0]&0xC0)>>6; - if (type == REDIS_RDB_6BITLEN) { - /* Read a 6 bit len */ - return buf[0]&0x3F; - } else if (type == REDIS_RDB_ENCVAL) { - /* Read a 6 bit len encoding type */ - if (isencoded) *isencoded = 1; - return buf[0]&0x3F; - } else if (type == REDIS_RDB_14BITLEN) { - /* Read a 14 bit len */ - if (rioRead(rdb,buf+1,1) == 0) return REDIS_RDB_LENERR; - return ((buf[0]&0x3F)<<8)|buf[1]; - } else { - /* Read a 32 bit len */ - if (rioRead(rdb,&len,4) == 0) return REDIS_RDB_LENERR; - return ntohl(len); - } -} - -/* Load an integer-encoded object from file 'fp', with the specified - * encoding type 'enctype'. If encode is true the function may return - * an integer-encoded object as reply, otherwise the returned object - * will always be encoded as a raw string. */ -robj *rdbLoadIntegerObject(rio *rdb, int enctype, int encode) { - unsigned char enc[4]; - long long val; - - if (enctype == REDIS_RDB_ENC_INT8) { - if (rioRead(rdb,enc,1) == 0) return NULL; - val = (signed char)enc[0]; - } else if (enctype == REDIS_RDB_ENC_INT16) { - uint16_t v; - if (rioRead(rdb,enc,2) == 0) return NULL; - v = enc[0]|(enc[1]<<8); - val = (int16_t)v; - } else if (enctype == REDIS_RDB_ENC_INT32) { - uint32_t v; - if (rioRead(rdb,enc,4) == 0) return NULL; - v = enc[0]|(enc[1]<<8)|(enc[2]<<16)|(enc[3]<<24); - val = (int32_t)v; - } else { - val = 0; /* anti-warning */ - redisPanic("Unknown RDB integer encoding type"); - } - if (encode) - return createStringObjectFromLongLong(val); - else - return createObject(REDIS_STRING,sdsfromlonglong(val)); -} - -robj *rdbLoadLzfStringObject(rio *rdb) { - unsigned int len, clen; - unsigned char *c = NULL; - sds val = NULL; - - if ((clen = rdbLoadLen(rdb,NULL)) == REDIS_RDB_LENERR) return NULL; - if ((len = rdbLoadLen(rdb,NULL)) == REDIS_RDB_LENERR) return NULL; - if ((c = zmalloc(clen)) == NULL) goto err; - if ((val = sdsnewlen(NULL,len)) == NULL) goto err; - if (rioRead(rdb,c,clen) == 0) goto err; - if (lzf_decompress(c,clen,val,len) == 0) goto err; - zfree(c); - return createObject(REDIS_STRING,val); -err: - zfree(c); - sdsfree(val); - return NULL; -} - -robj *rdbGenericLoadStringObject(rio *rdb, int encode) { - int isencoded; - uint32_t len; - sds val; - - len = rdbLoadLen(rdb,&isencoded); - if (isencoded) { - switch(len) { - case REDIS_RDB_ENC_INT8: - case REDIS_RDB_ENC_INT16: - case REDIS_RDB_ENC_INT32: - return rdbLoadIntegerObject(rdb,len,encode); - case REDIS_RDB_ENC_LZF: - return rdbLoadLzfStringObject(rdb); - default: - redisPanic("Unknown RDB encoding type"); - } - } - - if (len == REDIS_RDB_LENERR) return NULL; - val = sdsnewlen(NULL,len); - if (len && rioRead(rdb,val,len) == 0) { - sdsfree(val); - return NULL; - } - return createObject(REDIS_STRING,val); -} - -robj *rdbLoadStringObject(rio *rdb) { - return rdbGenericLoadStringObject(rdb,0); -} - -robj *rdbLoadEncodedStringObject(rio *rdb) { - return rdbGenericLoadStringObject(rdb,1); -} - -/* For information about double serialization check rdbSaveDoubleValue() */ -int rdbLoadDoubleValue(rio *rdb, double *val) { - char buf[128]; - unsigned char len; - - if (rioRead(rdb,&len,1) == 0) return -1; - switch(len) { - case 255: *val = R_NegInf; return 0; - case 254: *val = R_PosInf; return 0; - case 253: *val = R_Nan; return 0; - default: - if (rioRead(rdb,buf,len) == 0) return -1; - buf[len] = '\0'; - sscanf(buf, "%lg", val); - return 0; - } -} - /* Load a Redis object of the specified type from the specified file. * On success a newly allocated object is returned, otherwise NULL. */ robj *rdbLoadObject(int rdbtype, rio *rdb) { diff --git a/src/rdb.h b/src/rdb.h index 93185fc3..fec16ffb 100644 --- a/src/rdb.h +++ b/src/rdb.h @@ -7,6 +7,33 @@ /* TBD: include only necessary headers. */ #include "redis.h" +/* Defines related to the dump file format. To store 32 bits lengths for short + * keys requires a lot of space, so we check the most significant 2 bits of + * the first byte to interpreter the length: + * + * 00|000000 => if the two MSB are 00 the len is the 6 bits of this byte + * 01|000000 00000000 => 01, the len is 14 byes, 6 bits + 8 bits of next byte + * 10|000000 [32 bit integer] => if it's 01, a full 32 bit len will follow + * 11|000000 this means: specially encoded object will follow. The six bits + * number specify the kind of object that follows. + * See the REDIS_RDB_ENC_* defines. + * + * Lenghts up to 63 are stored using a single byte, most DB keys, and may + * values, will fit inside. */ +#define REDIS_RDB_6BITLEN 0 +#define REDIS_RDB_14BITLEN 1 +#define REDIS_RDB_32BITLEN 2 +#define REDIS_RDB_ENCVAL 3 +#define REDIS_RDB_LENERR UINT_MAX + +/* When a length of a string object stored on disk has the first two bits + * set, the remaining two bits specify a special encoding for the object + * accordingly to the following defines: */ +#define REDIS_RDB_ENC_INT8 0 /* 8 bit signed integer */ +#define REDIS_RDB_ENC_INT16 1 /* 16 bit signed integer */ +#define REDIS_RDB_ENC_INT32 2 /* 32 bit signed integer */ +#define REDIS_RDB_ENC_LZF 3 /* string compressed with FASTLZ */ + /* Dup object types to RDB object types. Only reason is readability (are we * dealing with RDB types or with in-memory object types?). */ #define REDIS_RDB_TYPE_STRING 0 @@ -32,6 +59,14 @@ /* Test if a type is an opcode. */ #define rdbIsOpcode(t) (t >= 253 && t <= 255) +int rdbSaveType(rio *rdb, unsigned char type); +int rdbLoadType(rio *rdb); +int rdbSaveTime(rio *rdb, time_t t); +time_t rdbLoadTime(rio *rdb); +int rdbSaveLen(rio *rdb, uint32_t len); +uint32_t rdbLoadLen(rio *rdb, int *isencoded); +int rdbSaveObjectType(rio *rdb, robj *o); +int rdbLoadObjectType(rio *rdb); int rdbLoad(char *filename); int rdbSaveBackground(char *filename); void rdbRemoveTempFile(pid_t childpid); @@ -42,12 +77,6 @@ off_t rdbSavedObjectPages(robj *o); robj *rdbLoadObject(int type, rio *rdb); void backgroundSaveDoneHandler(int exitcode, int bysignal); int rdbSaveKeyValuePair(rio *rdb, robj *key, robj *val, time_t expireitme, time_t now); -int rdbLoadType(rio *rdb); -time_t rdbLoadTime(rio *rdb); robj *rdbLoadStringObject(rio *rdb); -int rdbSaveType(rio *rdb, unsigned char type); -int rdbSaveLen(rio *rdb, uint32_t len); -int rdbSaveObjectType(rio *rdb, robj *o); -int rdbLoadObjectType(rio *rdb); #endif diff --git a/src/redis.h b/src/redis.h index 5cf9dcad..3fd13e2e 100644 --- a/src/redis.h +++ b/src/redis.h @@ -85,33 +85,6 @@ #define REDIS_ENCODING_INTSET 6 /* Encoded as intset */ #define REDIS_ENCODING_SKIPLIST 7 /* Encoded as skiplist */ -/* Defines related to the dump file format. To store 32 bits lengths for short - * keys requires a lot of space, so we check the most significant 2 bits of - * the first byte to interpreter the length: - * - * 00|000000 => if the two MSB are 00 the len is the 6 bits of this byte - * 01|000000 00000000 => 01, the len is 14 byes, 6 bits + 8 bits of next byte - * 10|000000 [32 bit integer] => if it's 01, a full 32 bit len will follow - * 11|000000 this means: specially encoded object will follow. The six bits - * number specify the kind of object that follows. - * See the REDIS_RDB_ENC_* defines. - * - * Lenghts up to 63 are stored using a single byte, most DB keys, and may - * values, will fit inside. */ -#define REDIS_RDB_6BITLEN 0 -#define REDIS_RDB_14BITLEN 1 -#define REDIS_RDB_32BITLEN 2 -#define REDIS_RDB_ENCVAL 3 -#define REDIS_RDB_LENERR UINT_MAX - -/* When a length of a string object stored on disk has the first two bits - * set, the remaining two bits specify a special encoding for the object - * accordingly to the following defines: */ -#define REDIS_RDB_ENC_INT8 0 /* 8 bit signed integer */ -#define REDIS_RDB_ENC_INT16 1 /* 16 bit signed integer */ -#define REDIS_RDB_ENC_INT32 2 /* 32 bit signed integer */ -#define REDIS_RDB_ENC_LZF 3 /* string compressed with FASTLZ */ - /* Scheduled IO opeations flags. */ #define REDIS_IO_LOAD 1 #define REDIS_IO_SAVE 2 -- 2.47.2