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-rw-r--r--ext/dbm/sdbm/sdbm.h91
1 files changed, 91 insertions, 0 deletions
diff --git a/ext/dbm/sdbm/sdbm.h b/ext/dbm/sdbm/sdbm.h
new file mode 100644
index 0000000000..e2fc762aab
--- /dev/null
+++ b/ext/dbm/sdbm/sdbm.h
@@ -0,0 +1,91 @@
+/*
+ * sdbm - ndbm work-alike hashed database library
+ * based on Per-Ake Larson's Dynamic Hashing algorithms. BIT 18 (1978).
+ * author: oz@nexus.yorku.ca
+ * status: public domain.
+ */
+#define DBLKSIZ 4096
+#define PBLKSIZ 1024
+#define PAIRMAX 1008 /* arbitrary on PBLKSIZ-N */
+#define SPLTMAX 10 /* maximum allowed splits */
+ /* for a single insertion */
+#define DIRFEXT ".dir"
+#define PAGFEXT ".pag"
+
+typedef struct {
+ int dirf; /* directory file descriptor */
+ int pagf; /* page file descriptor */
+ int flags; /* status/error flags, see below */
+ long maxbno; /* size of dirfile in bits */
+ long curbit; /* current bit number */
+ long hmask; /* current hash mask */
+ long blkptr; /* current block for nextkey */
+ int keyptr; /* current key for nextkey */
+ long blkno; /* current page to read/write */
+ long pagbno; /* current page in pagbuf */
+ char pagbuf[PBLKSIZ]; /* page file block buffer */
+ long dirbno; /* current block in dirbuf */
+ char dirbuf[DBLKSIZ]; /* directory file block buffer */
+} DBM;
+
+#define DBM_RDONLY 0x1 /* data base open read-only */
+#define DBM_IOERR 0x2 /* data base I/O error */
+
+/*
+ * utility macros
+ */
+#define sdbm_rdonly(db) ((db)->flags & DBM_RDONLY)
+#define sdbm_error(db) ((db)->flags & DBM_IOERR)
+
+#define sdbm_clearerr(db) ((db)->flags &= ~DBM_IOERR) /* ouch */
+
+#define sdbm_dirfno(db) ((db)->dirf)
+#define sdbm_pagfno(db) ((db)->pagf)
+
+typedef struct {
+ char *dptr;
+ int dsize;
+} datum;
+
+extern datum nullitem;
+
+#ifdef __STDC__
+#define proto(p) p
+#else
+#define proto(p) ()
+#endif
+
+/*
+ * flags to sdbm_store
+ */
+#define DBM_INSERT 0
+#define DBM_REPLACE 1
+
+/*
+ * ndbm interface
+ */
+extern DBM *sdbm_open proto((char *, int, int));
+extern void sdbm_close proto((DBM *));
+extern datum sdbm_fetch proto((DBM *, datum));
+extern int sdbm_delete proto((DBM *, datum));
+extern int sdbm_store proto((DBM *, datum, datum, int));
+extern datum sdbm_firstkey proto((DBM *));
+extern datum sdbm_nextkey proto((DBM *));
+
+/*
+ * other
+ */
+extern DBM *sdbm_prep proto((char *, char *, int, int));
+extern long sdbm_hash proto((char *, int));
+
+#ifndef SDBM_ONLY
+#define dbm_open sdbm_open;
+#define dbm_close sdbm_close;
+#define dbm_fetch sdbm_fetch;
+#define dbm_store sdbm_store;
+#define dbm_delete sdbm_delete;
+#define dbm_firstkey sdbm_firstkey;
+#define dbm_nextkey sdbm_nextkey;
+#define dbm_error sdbm_error;
+#define dbm_clearerr sdbm_clearerr;
+#endif