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-rw-r--r--sds.h190
1 files changed, 173 insertions, 17 deletions
diff --git a/sds.h b/sds.h
index 19a2abd..1aadace 100644
--- a/sds.h
+++ b/sds.h
@@ -1,6 +1,6 @@
-/* SDS (Simple Dynamic Strings), A C dynamic strings library.
+/* SDSLib, A C dynamic strings library
*
- * Copyright (c) 2006-2014, Salvatore Sanfilippo <antirez at gmail dot com>
+ * Copyright (c) 2006-2010, Salvatore Sanfilippo <antirez at gmail dot com>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
@@ -35,35 +35,188 @@
#include <sys/types.h>
#include <stdarg.h>
-#ifdef _MSC_VER
-#include "win32.h"
-#endif
+#include <stdint.h>
typedef char *sds;
-struct sdshdr {
- int len;
- int free;
+/* 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(f) ((f)>>SDS_TYPE_BITS)
static inline size_t sdslen(const sds s) {
- struct sdshdr *sh = (struct sdshdr *)(s-sizeof *sh);
- return sh->len;
+ unsigned char flags = s[-1];
+ switch(flags&SDS_TYPE_MASK) {
+ case SDS_TYPE_5:
+ return SDS_TYPE_5_LEN(flags);
+ 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) {
- struct sdshdr *sh = (struct sdshdr *)(s-sizeof *sh);
- return sh->free;
+ unsigned char flags = s[-1];
+ switch(flags&SDS_TYPE_MASK) {
+ 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) {
+ unsigned char flags = s[-1];
+ switch(flags&SDS_TYPE_MASK) {
+ 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) {
+ unsigned char flags = s[-1];
+ switch(flags&SDS_TYPE_MASK) {
+ case SDS_TYPE_5:
+ {
+ unsigned char *fp = ((unsigned char*)s)-1;
+ unsigned char newlen = SDS_TYPE_5_LEN(flags)+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;
+ }
+}
+
+/* sdsalloc() = sdsavail() + sdslen() */
+static inline size_t sdsalloc(const sds s) {
+ unsigned char flags = s[-1];
+ switch(flags&SDS_TYPE_MASK) {
+ case SDS_TYPE_5:
+ return SDS_TYPE_5_LEN(flags);
+ 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) {
+ unsigned char flags = s[-1];
+ switch(flags&SDS_TYPE_MASK) {
+ 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;
+ }
}
sds sdsnewlen(const void *init, size_t initlen);
sds sdsnew(const char *init);
sds sdsempty(void);
-size_t sdslen(const sds s);
sds sdsdup(const sds s);
void sdsfree(sds s);
-size_t sdsavail(const sds s);
sds sdsgrowzero(sds s, size_t len);
sds sdscatlen(sds s, const void *t, size_t len);
sds sdscat(sds s, const char *t);
@@ -80,7 +233,7 @@ sds sdscatprintf(sds s, const char *fmt, ...);
#endif
sds sdscatfmt(sds s, char const *fmt, ...);
-void sdstrim(sds s, const char *cset);
+sds sdstrim(sds s, const char *cset);
void sdsrange(sds s, int start, int end);
void sdsupdatelen(sds s);
void sdsclear(sds s);
@@ -93,8 +246,7 @@ 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, size_t seplen);
-sds sdsjoinsds(sds *argv, int argc, const char *sep, size_t seplen);
+sds sdsjoin(char **argv, int argc, char *sep);
/* Low level functions exposed to the user API */
sds sdsMakeRoomFor(sds s, size_t addlen);
@@ -102,4 +254,8 @@ void sdsIncrLen(sds s, int incr);
sds sdsRemoveFreeSpace(sds s);
size_t sdsAllocSize(sds s);
+#ifdef REDIS_TEST
+int sdsTest(int argc, char *argv[]);
+#endif
+
#endif