diff options
Diffstat (limited to 'examples/redis-unstable/src/sds.h')
| -rw-r--r-- | examples/redis-unstable/src/sds.h | 340 |
1 files changed, 340 insertions, 0 deletions
diff --git a/examples/redis-unstable/src/sds.h b/examples/redis-unstable/src/sds.h new file mode 100644 index 0000000..3c02d7d --- /dev/null +++ b/examples/redis-unstable/src/sds.h @@ -0,0 +1,340 @@ +/* SDSLib 2.0 -- A C dynamic strings library + * + * Copyright (c) 2006-Present, Redis Ltd. + * All rights reserved. + * + * Copyright (c) 2024-present, Valkey contributors. + * All rights reserved. + * + * Licensed under your choice of (a) the Redis Source Available License 2.0 + * (RSALv2); or (b) the Server Side Public License v1 (SSPLv1); or (c) the + * GNU Affero General Public License v3 (AGPLv3). + */ + +#ifndef __SDS_H +#define __SDS_H + +#define SDS_MAX_PREALLOC (1024*1024) +extern const char *SDS_NOINIT; + +#include <sys/types.h> +#include <stdarg.h> +#include <stdint.h> + +typedef char *sds; + +/* Note: sdshdr5 is never used, we just access the flags byte directly. + * However is here to document the layout of type 5 SDS strings. */ +struct __attribute__ ((__packed__)) sdshdr5 { + unsigned char flags; /* 3 lsb of type, and 5 msb of string length */ + char buf[]; +}; +struct __attribute__ ((__packed__)) sdshdr8 { + uint8_t len; /* used */ + uint8_t alloc; /* excluding the header and null terminator */ + unsigned char flags; /* 3 lsb of type, 5 unused bits */ + char buf[]; +}; +struct __attribute__ ((__packed__)) sdshdr16 { + uint16_t len; /* used */ + uint16_t alloc; /* excluding the header and null terminator */ + unsigned char flags; /* 3 lsb of type, 5 unused bits */ + char buf[]; +}; +struct __attribute__ ((__packed__)) sdshdr32 { + uint32_t len; /* used */ + uint32_t alloc; /* excluding the header and null terminator */ + unsigned char flags; /* 3 lsb of type, 5 unused bits */ + char buf[]; +}; +struct __attribute__ ((__packed__)) sdshdr64 { + uint64_t len; /* used */ + uint64_t alloc; /* excluding the header and null terminator */ + unsigned char flags; /* 3 lsb of type, 5 unused bits */ + char buf[]; +}; + +#define SDS_TYPE_5 0 +#define SDS_TYPE_8 1 +#define SDS_TYPE_16 2 +#define SDS_TYPE_32 3 +#define SDS_TYPE_64 4 +#define SDS_TYPE_MASK 7 +#define SDS_TYPE_BITS 3 +#define SDS_HDR_VAR(T,s) struct sdshdr##T *sh = (void*)((s)-(sizeof(struct sdshdr##T))); +#define SDS_HDR(T,s) ((struct sdshdr##T *)((s)-(sizeof(struct sdshdr##T)))) +#define SDS_TYPE_5_LEN(s) (((unsigned char)(s[-1])) >> SDS_TYPE_BITS) + +static inline unsigned char sdsType(sds s) { + unsigned char flags = s[-1]; + return flags & SDS_TYPE_MASK; +} + +/* Returns a user data bit stored in the SDS header by sdsSetAuxBit. The bit + * index is 0-4. Returns 0 or 1. Always returns 0 for SDS_TYPE_5. */ +static inline int sdsGetAuxBit(sds s, int bit) { + if (sdsType(s) == SDS_TYPE_5) + return 0; + + unsigned char flags = s[-1]; + return (flags & (1U << (SDS_TYPE_BITS + bit))) != 0U; +} + +/* Stores a bit in an unused area in the SDS header, except for SDS_TYPE_5. The + * bit index is 0-4. The value is 0 or 1. The aux bits are lost if the SDS is + * auto-resized. This is only for special uses like immutable SDS embedded in + * other structures. */ +static inline void sdsSetAuxBit(sds s, int bit, int value) { + if (sdsType(s) == SDS_TYPE_5) return; + unsigned char flags = s[-1]; + if (value) { + flags |= 1U << (SDS_TYPE_BITS + bit); + } else { + flags &= ~(1U << (SDS_TYPE_BITS + bit)); + } + s[-1] = (char)flags; +} + +static inline size_t sdslen(const sds s) { + switch (sdsType(s)) { + case SDS_TYPE_5: return SDS_TYPE_5_LEN(s); + case SDS_TYPE_8: + return SDS_HDR(8,s)->len; + case SDS_TYPE_16: + return SDS_HDR(16,s)->len; + case SDS_TYPE_32: + return SDS_HDR(32,s)->len; + case SDS_TYPE_64: + return SDS_HDR(64,s)->len; + } + return 0; +} + +static inline size_t sdsavail(const sds s) { + switch(sdsType(s)) { + case SDS_TYPE_5: { + return 0; + } + case SDS_TYPE_8: { + SDS_HDR_VAR(8,s); + return sh->alloc - sh->len; + } + case SDS_TYPE_16: { + SDS_HDR_VAR(16,s); + return sh->alloc - sh->len; + } + case SDS_TYPE_32: { + SDS_HDR_VAR(32,s); + return sh->alloc - sh->len; + } + case SDS_TYPE_64: { + SDS_HDR_VAR(64,s); + return sh->alloc - sh->len; + } + } + return 0; +} + +static inline void sdssetlen(sds s, size_t newlen) { + switch(sdsType(s)) { + case SDS_TYPE_5: + { + unsigned char *fp = ((unsigned char*)s)-1; + *fp = SDS_TYPE_5 | (newlen << SDS_TYPE_BITS); + } + break; + case SDS_TYPE_8: + SDS_HDR(8,s)->len = newlen; + break; + case SDS_TYPE_16: + SDS_HDR(16,s)->len = newlen; + break; + case SDS_TYPE_32: + SDS_HDR(32,s)->len = newlen; + break; + case SDS_TYPE_64: + SDS_HDR(64,s)->len = newlen; + break; + } +} + +static inline void sdsinclen(sds s, size_t inc) { + switch(sdsType(s)) { + case SDS_TYPE_5: + { + unsigned char *fp = ((unsigned char*)s)-1; + unsigned char newlen = SDS_TYPE_5_LEN(s)+inc; + *fp = SDS_TYPE_5 | (newlen << SDS_TYPE_BITS); + } + break; + case SDS_TYPE_8: + SDS_HDR(8,s)->len += inc; + break; + case SDS_TYPE_16: + SDS_HDR(16,s)->len += inc; + break; + case SDS_TYPE_32: + SDS_HDR(32,s)->len += inc; + break; + case SDS_TYPE_64: + SDS_HDR(64,s)->len += inc; + break; + } +} + +/* Return the total size of the allocation of the specified sds string, + * including: + * 1) The sds header before the pointer. + * 2) The string. + * 3) The free buffer at the end if any. + * 4) The implicit null term. + */ +static inline size_t sdsAllocSize(sds s) { + switch(sdsType(s)) { + case SDS_TYPE_5: + return sizeof(struct sdshdr5) + SDS_TYPE_5_LEN(s) + 1; + case SDS_TYPE_8: + return sizeof(struct sdshdr8) + SDS_HDR(8,s)->alloc + 1; + case SDS_TYPE_16: + return sizeof(struct sdshdr16) + SDS_HDR(16,s)->alloc + 1; + case SDS_TYPE_32: + return sizeof(struct sdshdr32) + SDS_HDR(32,s)->alloc + 1; + case SDS_TYPE_64: + return sizeof(struct sdshdr64) + SDS_HDR(64,s)->alloc + 1; + } + return 0; +} + +/* sdsalloc() = sdsavail() + sdslen() */ +static inline size_t sdsalloc(const sds s) { + switch(sdsType(s)) { + case SDS_TYPE_5: + return SDS_TYPE_5_LEN(s); + case SDS_TYPE_8: + return SDS_HDR(8,s)->alloc; + case SDS_TYPE_16: + return SDS_HDR(16,s)->alloc; + case SDS_TYPE_32: + return SDS_HDR(32,s)->alloc; + case SDS_TYPE_64: + return SDS_HDR(64,s)->alloc; + } + return 0; +} + +static inline void sdssetalloc(sds s, size_t newlen) { + switch(sdsType(s)) { + case SDS_TYPE_5: + /* Nothing to do, this type has no total allocation info. */ + break; + case SDS_TYPE_8: + SDS_HDR(8,s)->alloc = newlen; + break; + case SDS_TYPE_16: + SDS_HDR(16,s)->alloc = newlen; + break; + case SDS_TYPE_32: + SDS_HDR(32,s)->alloc = newlen; + break; + case SDS_TYPE_64: + SDS_HDR(64,s)->alloc = newlen; + break; + } +} + +static inline int sdsHdrSize(char type) { + switch(type&SDS_TYPE_MASK) { + case SDS_TYPE_5: + return sizeof(struct sdshdr5); + case SDS_TYPE_8: + return sizeof(struct sdshdr8); + case SDS_TYPE_16: + return sizeof(struct sdshdr16); + case SDS_TYPE_32: + return sizeof(struct sdshdr32); + case SDS_TYPE_64: + return sizeof(struct sdshdr64); + } + return 0; +} + +sds sdsnewlen(const void *init, size_t initlen); +sds sdstrynewlen(const void *init, size_t initlen); +sds sdsnew(const char *init); +sds sdsnewplacement(char *buf, size_t bufsize, char type, const char *init, size_t initlen); + +sds sdsempty(void); +sds sdsdup(const sds s); +void sdsfree(sds s); +void sdsfreegeneric(void *s); +void sdsfreeusable(sds s, size_t *usable); +sds sdsgrowzero(sds s, size_t len); +sds sdscatlen(sds s, const void *t, size_t len); +sds sdscat(sds s, const char *t); +sds sdscatsds(sds s, const sds t); +sds sdscpylen(sds s, const char *t, size_t len); +sds sdscpy(sds s, const char *t); + +sds sdscatvprintf(sds s, const char *fmt, va_list ap); +#ifdef __GNUC__ +sds sdscatprintf(sds s, const char *fmt, ...) + __attribute__((format(printf, 2, 3))); +#else +sds sdscatprintf(sds s, const char *fmt, ...); +#endif + +sds sdscatfmt(sds s, char const *fmt, ...); +sds sdstrim(sds s, const char *cset); +void sdssubstr(sds s, size_t start, size_t len); +void sdsrange(sds s, ssize_t start, ssize_t end); +void sdsupdatelen(sds s); +void sdsclear(sds s); +int sdscmp(const sds s1, const sds s2); +sds *sdssplitlen(const char *s, ssize_t len, const char *sep, int seplen, int *count); +void sdsfreesplitres(sds *tokens, int count); +void sdstolower(sds s); +void sdstoupper(sds s); +sds sdsfromlonglong(long long value); +sds sdscatrepr(sds s, const char *p, size_t len); +sds *sdssplitargs(const char *line, int *argc); +sds sdsmapchars(sds s, const char *from, const char *to, size_t setlen); +sds sdsjoin(char **argv, int argc, char *sep); +sds sdsjoinsds(sds *argv, int argc, const char *sep, size_t seplen); +int sdsneedsrepr(const sds s); + +/* Callback for sdstemplate. The function gets called by sdstemplate + * every time a variable needs to be expanded. The variable name is + * provided as variable, and the callback is expected to return a + * substitution value. Returning a NULL indicates an error. + */ +typedef sds (*sdstemplate_callback_t)(const sds variable, void *arg); +sds sdstemplate(const char *template, sdstemplate_callback_t cb_func, void *cb_arg); + +/* Low level functions exposed to the user API */ +char sdsReqType(size_t string_size); +sds sdsMakeRoomFor(sds s, size_t addlen); +sds sdsMakeRoomForNonGreedy(sds s, size_t addlen); +void sdsIncrLen(sds s, ssize_t incr); +sds sdsRemoveFreeSpace(sds s, int would_regrow); +sds sdsResize(sds s, size_t size, int would_regrow); +void *sdsAllocPtr(sds s); + +/* Returns the minimum required size to store an sds string of the given length + * and type. */ +static inline size_t sdsReqSize(size_t len, char type) { + return len + sdsHdrSize(type) + 1; +} + +/* Export the allocator used by SDS to the program using SDS. + * Sometimes the program SDS is linked to, may use a different set of + * allocators, but may want to allocate or free things that SDS will + * respectively free or allocate. */ +void *sds_malloc(size_t size); +void *sds_realloc(void *ptr, size_t size); +void sds_free(void *ptr); + +#ifdef REDIS_TEST +int sdsTest(int argc, char *argv[], int flags); +#endif + +#endif |
