ref: 0339e9ac44b4aed285391727ce3d6e3e1afd173e
dir: /sys/include/ndb.h/
#pragma src "/sys/src/libndb" #pragma lib "libndb.a" /* * this include file requires includes of <u.h> and <bio.h> */ typedef struct Ndb Ndb; typedef struct Ndbtuple Ndbtuple; typedef struct Ndbhf Ndbhf; typedef struct Ndbs Ndbs; typedef struct Ndbcache Ndbcache; #pragma incomplete Ndbhf #pragma incomplete Ndbcache enum { Ndbalen= 32, /* max attribute length */ Ndbvlen= 64, /* max value length */ }; /* * the database */ struct Ndb { Ndb *next; Biobufhdr b; /* buffered input file */ uchar buf[256]; /* and its buffer */ ulong mtime; /* mtime of db file */ Qid qid; /* qid of db file */ char file[128]; /* path name of db file */ ulong length; /* length of db file */ int nohash; /* don't look for hash files */ Ndbhf *hf; /* open hash files */ int ncache; /* size of tuple cache */ Ndbcache *cache; /* cached entries */ }; /* * a parsed entry, doubly linked */ struct Ndbtuple { char attr[Ndbalen]; /* attribute name */ char *val; /* value(s) */ Ndbtuple *entry; /* next tuple in this entry */ Ndbtuple *line; /* next tuple on this line */ ulong ptr; /* (for the application - starts 0) */ char valbuf[Ndbvlen]; /* initial allocation for value */ }; /* * each hash file is of the form * * +---------------------------------------+ * | mtime of db file (4 bytes) | * +---------------------------------------+ * | size of table (in entries - 4 bytes) | * +---------------------------------------+ * | hash table | * +---------------------------------------+ * | hash chains | * +---------------------------------------+ * * hash collisions are resolved using chained entries added to the * the end of the hash table. * * Hash entries are of the form * * +-------------------------------+ * | offset (3 bytes) | * +-------------------------------+ * * Chain entries are of the form * * +-------------------------------+ * | offset1 (3 bytes) | * +-------------------------------+ * | offset2 (3 bytes) | * +-------------------------------+ * * The top bit of an offset set to 1 indicates a pointer to a hash chain entry. */ #define NDBULLEN 4 /* unsigned long length in bytes */ #define NDBPLEN 3 /* pointer length in bytes */ #define NDBHLEN (2*NDBULLEN) /* hash file header length in bytes */ /* * finger pointing to current point in a search */ struct Ndbs { Ndb *db; /* data base file being searched */ Ndbhf *hf; /* hash file being searched */ int type; ulong ptr; /* current pointer */ ulong ptr1; /* next pointer */ Ndbtuple *t; /* last attribute value pair found */ }; /* * bit defs for pointers in hash files */ #define NDBSPEC (1<<23) #define NDBCHAIN NDBSPEC /* points to a collision chain */ #define NDBNAP (NDBSPEC|1) /* not a pointer */ /* * macros for packing and unpacking pointers */ #define NDBPUTP(v,a) { (a)[0] = v; (a)[1] = (v)>>8; (a)[2] = (v)>>16; } #define NDBGETP(a) ((a)[0] | ((a)[1]<<8) | ((a)[2]<<16)) /* * macros for packing and unpacking unsigned longs */ #define NDBPUTUL(v,a) { (a)[0] = v; (a)[1] = (v)>>8; (a)[2] = (v)>>16; (a)[3] = (v)>>24; } #define NDBGETUL(a) ((a)[0] | ((a)[1]<<8) | ((a)[2]<<16) | ((a)[3]<<24)) #define NDB_IPlen 16 char* csgetvalue(char*, char*, char*, char*, Ndbtuple**); Ndbtuple* csipinfo(char*, char*, char*, char**, int); Ndbtuple* dnsquery(char*, char*, char*); char* ipattr(char*); Ndb* ndbcat(Ndb*, Ndb*); int ndbchanged(Ndb*); void ndbclose(Ndb*); Ndbtuple* ndbconcatenate(Ndbtuple*, Ndbtuple*); Ndbtuple* ndbdiscard(Ndbtuple*, Ndbtuple*); void ndbfree(Ndbtuple*); Ndbtuple* ndbgetipaddr(Ndb*, char*); char* ndbgetvalue(Ndb*, Ndbs*, char*, char*, char*, Ndbtuple**); Ndbtuple* ndbfindattr(Ndbtuple*, Ndbtuple*, char*); ulong ndbhash(char*, int); Ndbtuple* ndbipinfo(Ndb*, char*, char*, char**, int); Ndbtuple* ndbnew(char*, char*); Ndb* ndbopen(char*); Ndbtuple* ndbparse(Ndb*); int ndbreopen(Ndb*); Ndbtuple* ndbreorder(Ndbtuple*, Ndbtuple*); Ndbtuple* ndbsearch(Ndb*, Ndbs*, char*, char*); void ndbsetval(Ndbtuple*, char*, int); Ndbtuple* ndbsnext(Ndbs*, char*, char*); Ndbtuple* ndbsubstitute(Ndbtuple*, Ndbtuple*, Ndbtuple*); Ndbtuple* ndbdedup(Ndbtuple*); void ndbsetmalloctag(Ndbtuple*, uintptr);