Class: DBM

Inherits:
Object
  • Object
show all
Includes:
Enumerable
Defined in:
dbm.c

Constant Summary

READER =

Indicates that dbm_open() should open the database in read-only mode

INT2FIX(O_RDONLY|RUBY_DBM_RW_BIT)
WRITER =

Indicates that dbm_open() should open the database in read/write mode

INT2FIX(O_RDWR|RUBY_DBM_RW_BIT)
WRCREAT =

Indicates that dbm_open() should open the database in read/write mode, and create it if it does not already exist

INT2FIX(O_RDWR|O_CREAT|RUBY_DBM_RW_BIT)
NEWDB =

Indicates that dbm_open() should open the database in read/write mode, create it if it does not already exist, and delete all contents if it does already exist.

INT2FIX(O_RDWR|O_CREAT|O_TRUNC|RUBY_DBM_RW_BIT)
VERSION =
  • “ndbm (4.3BSD)”

  • “Berkeley DB 4.8.30: (April 9, 2010)”

  • “Berkeley DB (unknown)” (4.4BSD, maybe)

  • “GDBM version 1.8.3. 10/15/2002 (built Jul 1 2011 12:32:45)”

  • “QDBM 1.8.78”

Identifies ndbm library version.

Examples

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#new(filename[, mode[, flags]]) ⇒ Object

Open a dbm database with the specified name, which can include a directory path. Any file extensions needed will be supplied automatically by the dbm library. For example, Berkeley DB appends '.db', and GNU gdbm uses two physical files with extensions '.dir' and '.pag'.

The mode should be an integer, as for Unix chmod.

Flags should be one of READER, WRITER, WRCREAT or NEWDB.



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# File 'dbm.c', line 125

static VALUE
fdbm_initialize(int argc, VALUE *argv, VALUE obj)
{
    volatile VALUE file;
    VALUE vmode, vflags;
    DBM *dbm;
    struct dbmdata *dbmp;
    int mode, flags = 0;

    if (rb_scan_args(argc, argv, "12", &file, &vmode, &vflags) == 1) {
	mode = 0666;		/* default value */
    }
    else if (NIL_P(vmode)) {
	mode = -1;		/* return nil if DB not exist */
    }
    else {
	mode = NUM2INT(vmode);
    }

    if (!NIL_P(vflags))
        flags = NUM2INT(vflags);

    FilePathValue(file);

    /*
     * Note:
     * gdbm 1.10 works with O_CLOEXEC.  gdbm 1.9.1 silently ignore it.
     */
#ifndef O_CLOEXEC
#   define O_CLOEXEC 0
#endif

    if (flags & RUBY_DBM_RW_BIT) {
        flags &= ~RUBY_DBM_RW_BIT;
        dbm = dbm_open(RSTRING_PTR(file), flags|O_CLOEXEC, mode);
    }
    else {
        dbm = 0;
        if (mode >= 0) {
            dbm = dbm_open(RSTRING_PTR(file), O_RDWR|O_CREAT|O_CLOEXEC, mode);
        }
        if (!dbm) {
            dbm = dbm_open(RSTRING_PTR(file), O_RDWR|O_CLOEXEC, 0);
        }
        if (!dbm) {
            dbm = dbm_open(RSTRING_PTR(file), O_RDONLY|O_CLOEXEC, 0);
        }
    }

    if (dbm) {
    /*
     * History of dbm_pagfno() and dbm_dirfno() in ndbm and its compatibles.
     * (dbm_pagfno() and dbm_dirfno() is not standardized.)
     *
     * 1986: 4.3BSD provides ndbm.
     *       It provides dbm_pagfno() and dbm_dirfno() as macros.
     * 1991: gdbm-1.5 provides them as functions.
     *       They returns a same descriptor.
     *       (Earlier releases may have the functions too.)
     * 1991: Net/2 provides Berkeley DB.
     *       It doesn't provide dbm_pagfno() and dbm_dirfno().
     * 1992: 4.4BSD Alpha provides Berkeley DB with dbm_dirfno() as a function.
     *       dbm_pagfno() is a macro as DBM_PAGFNO_NOT_AVAILABLE.
     * 1997: Berkeley DB 2.0 is released by Sleepycat Software, Inc.
     *       It defines dbm_pagfno() and dbm_dirfno() as macros.
     * 2011: gdbm-1.9 creates a separate dir file.
     *       dbm_pagfno() and dbm_dirfno() returns different descriptors.
     */
#if defined(HAVE_DBM_PAGFNO)
        rb_fd_fix_cloexec(dbm_pagfno(dbm));
#endif
#if defined(HAVE_DBM_DIRFNO)
        rb_fd_fix_cloexec(dbm_dirfno(dbm));
#endif

#if defined(RUBYDBM_DB_HEADER) && defined(HAVE_TYPE_DBC)
    /* Disable Berkeley DB error messages such as:
     * DB->put: attempt to modify a read-only database */
        ((DBC*)dbm)->dbp->set_errfile(((DBC*)dbm)->dbp, NULL);
#endif
    }

    if (!dbm) {
	if (mode == -1) return Qnil;
	rb_sys_fail_str(file);
    }

    dbmp = ALLOC(struct dbmdata);
    DATA_PTR(obj) = dbmp;
    dbmp->di_dbm = dbm;
    dbmp->di_size = -1;

    return obj;
}

Class Method Details

.open(filename[, mode[, flags]]) ⇒ Object .open(filename[, mode[, flags]]) {|dbm| ... } ⇒ Object

Open a dbm database and yields it if a block is given. See also DBM.new.

Overloads:

  • .open(filename[, mode[, flags]]) {|dbm| ... } ⇒ Object

    Yields:

    • (dbm)


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# File 'dbm.c', line 228

static VALUE
fdbm_s_open(int argc, VALUE *argv, VALUE klass)
{
    VALUE obj = Data_Wrap_Struct(klass, 0, free_dbm, 0);

    if (NIL_P(fdbm_initialize(argc, argv, obj))) {
	return Qnil;
    }

    if (rb_block_given_p()) {
        return rb_ensure(rb_yield, obj, fdbm_close, obj);
    }

    return obj;
}

Instance Method Details

#[](key) ⇒ nil

Return a value from the database by locating the key string provided. If the key is not found, returns nil.

Returns:

  • (nil)


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# File 'dbm.c', line 276

static VALUE
fdbm_aref(VALUE obj, VALUE keystr)
{
    return fdbm_fetch(obj, keystr, Qnil);
}

#store(key, value) ⇒ Object #[]=(key) ⇒ Object

Stores the specified string value in the database, indexed via the string key provided.



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# File 'dbm.c', line 627

static VALUE
fdbm_store(VALUE obj, VALUE keystr, VALUE valstr)
{
    datum key, val;
    struct dbmdata *dbmp;
    DBM *dbm;

    fdbm_modify(obj);
    keystr = rb_obj_as_string(keystr);
    valstr = rb_obj_as_string(valstr);

    key.dptr = RSTRING_PTR(keystr);
    key.dsize = RSTRING_DSIZE(keystr);

    val.dptr = RSTRING_PTR(valstr);
    val.dsize = RSTRING_DSIZE(valstr);

    GetDBM2(obj, dbmp, dbm);
    dbmp->di_size = -1;
    if (dbm_store(dbm, key, val, DBM_REPLACE)) {
	dbm_clearerr(dbm);
	if (errno == EPERM) rb_sys_fail(0);
	rb_raise(rb_eDBMError, "dbm_store failed");
    }

    return valstr;
}

#clearObject

Deletes all data from the database.



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# File 'dbm.c', line 529

static VALUE
fdbm_clear(VALUE obj)
{
    datum key;
    struct dbmdata *dbmp;
    DBM *dbm;

    fdbm_modify(obj);
    GetDBM2(obj, dbmp, dbm);
    dbmp->di_size = -1;
    while (key = dbm_firstkey(dbm), key.dptr) {
	if (dbm_delete(dbm, key)) {
	    rb_raise(rb_eDBMError, "dbm_delete failed");
	}
    }
    dbmp->di_size = 0;

    return obj;
}

#closeObject

Closes the database.



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# File 'dbm.c', line 74

static VALUE
fdbm_close(VALUE obj)
{
    struct dbmdata *dbmp;

    GetDBM(obj, dbmp);
    dbm_close(dbmp->di_dbm);
    dbmp->di_dbm = 0;

    return Qnil;
}

#closed?Boolean

Returns true if the database is closed, false otherwise.

Returns:

  • (Boolean)

Returns:

  • (Boolean)


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# File 'dbm.c', line 92

static VALUE
fdbm_closed(VALUE obj)
{
    struct dbmdata *dbmp;

    Data_Get_Struct(obj, struct dbmdata, dbmp);
    if (dbmp == 0)
	return Qtrue;
    if (dbmp->di_dbm == 0)
	return Qtrue;

    return Qfalse;
}

#delete(key) ⇒ Object

Deletes an entry from the database.



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# File 'dbm.c', line 405

static VALUE
fdbm_delete(VALUE obj, VALUE keystr)
{
    datum key, value;
    struct dbmdata *dbmp;
    DBM *dbm;
    VALUE valstr;
    long len;

    fdbm_modify(obj);
    ExportStringValue(keystr);
    len = RSTRING_LEN(keystr);
    if (TOO_LONG(len)) goto not_found;
    key.dptr = RSTRING_PTR(keystr);
    key.dsize = (DSIZE_TYPE)len;

    GetDBM2(obj, dbmp, dbm);

    value = dbm_fetch(dbm, key);
    if (value.dptr == 0) {
      not_found:
	if (rb_block_given_p()) return rb_yield(keystr);
	return Qnil;
    }

    /* need to save value before dbm_delete() */
    valstr = rb_tainted_str_new(value.dptr, value.dsize);

    if (dbm_delete(dbm, key)) {
	dbmp->di_size = -1;
	rb_raise(rb_eDBMError, "dbm_delete failed");
    }
    else if (dbmp->di_size >= 0) {
	dbmp->di_size--;
    }
    return valstr;
}

#reject! {|key, value| ... } ⇒ self #delete_if {|key, value| ... } ⇒ self

Deletes all entries for which the code block returns true. Returns self.

Overloads:

  • #reject! {|key, value| ... } ⇒ self

    Yields:

    Returns:

    • (self)
  • #delete_if {|key, value| ... } ⇒ self

    Yields:

    Returns:

    • (self)


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# File 'dbm.c', line 481

static VALUE
fdbm_delete_if(VALUE obj)
{
    datum key, val;
    struct dbmdata *dbmp;
    DBM *dbm;
    VALUE keystr, valstr;
    VALUE ret, ary = rb_ary_tmp_new(0);
    int i, status = 0;
    long n;

    fdbm_modify(obj);
    GetDBM2(obj, dbmp, dbm);
    n = dbmp->di_size;
    dbmp->di_size = -1;

    for (key = dbm_firstkey(dbm); key.dptr; key = dbm_nextkey(dbm)) {
	val = dbm_fetch(dbm, key);
	keystr = rb_tainted_str_new(key.dptr, key.dsize);
	OBJ_FREEZE(keystr);
	valstr = rb_tainted_str_new(val.dptr, val.dsize);
        ret = rb_protect(rb_yield, rb_assoc_new(rb_str_dup(keystr), valstr), &status);
        if (status != 0) break;
	if (RTEST(ret)) rb_ary_push(ary, keystr);
	GetDBM2(obj, dbmp, dbm);
    }

    for (i = 0; i < RARRAY_LEN(ary); i++) {
	keystr = RARRAY_PTR(ary)[i];
	key.dptr = RSTRING_PTR(keystr);
	key.dsize = (DSIZE_TYPE)RSTRING_LEN(keystr);
	if (dbm_delete(dbm, key)) {
	    rb_raise(rb_eDBMError, "dbm_delete failed");
	}
    }
    if (status) rb_jump_tag(status);
    if (n > 0) dbmp->di_size = n - RARRAY_LEN(ary);
    rb_ary_clear(ary);

    return obj;
}

#each_pair {|key, value| ... } ⇒ self

Calls the block once for each [key, value] pair in the database. Returns self.

Yields:

Returns:

  • (self)


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# File 'dbm.c', line 762

static VALUE
fdbm_each_pair(VALUE obj)
{
    datum key, val;
    DBM *dbm;
    struct dbmdata *dbmp;
    VALUE keystr, valstr;

    RETURN_ENUMERATOR(obj, 0, 0);

    GetDBM2(obj, dbmp, dbm);

    for (key = dbm_firstkey(dbm); key.dptr; key = dbm_nextkey(dbm)) {
	val = dbm_fetch(dbm, key);
	keystr = rb_tainted_str_new(key.dptr, key.dsize);
	valstr = rb_tainted_str_new(val.dptr, val.dsize);
	rb_yield(rb_assoc_new(keystr, valstr));
	GetDBM2(obj, dbmp, dbm);
    }

    return obj;
}

#each_key {|key| ... } ⇒ self

Calls the block once for each key string in the database. Returns self.

Yields:

Returns:

  • (self)


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# File 'dbm.c', line 738

static VALUE
fdbm_each_key(VALUE obj)
{
    datum key;
    struct dbmdata *dbmp;
    DBM *dbm;

    RETURN_ENUMERATOR(obj, 0, 0);

    GetDBM2(obj, dbmp, dbm);
    for (key = dbm_firstkey(dbm); key.dptr; key = dbm_nextkey(dbm)) {
	rb_yield(rb_tainted_str_new(key.dptr, key.dsize));
	GetDBM2(obj, dbmp, dbm);
    }
    return obj;
}

#each_pair {|key, value| ... } ⇒ self

Calls the block once for each [key, value] pair in the database. Returns self.

Yields:

Returns:

  • (self)


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# File 'dbm.c', line 762

static VALUE
fdbm_each_pair(VALUE obj)
{
    datum key, val;
    DBM *dbm;
    struct dbmdata *dbmp;
    VALUE keystr, valstr;

    RETURN_ENUMERATOR(obj, 0, 0);

    GetDBM2(obj, dbmp, dbm);

    for (key = dbm_firstkey(dbm); key.dptr; key = dbm_nextkey(dbm)) {
	val = dbm_fetch(dbm, key);
	keystr = rb_tainted_str_new(key.dptr, key.dsize);
	valstr = rb_tainted_str_new(val.dptr, val.dsize);
	rb_yield(rb_assoc_new(keystr, valstr));
	GetDBM2(obj, dbmp, dbm);
    }

    return obj;
}

#each_value {|value| ... } ⇒ self

Calls the block once for each value string in the database. Returns self.

Yields:

  • (value)

Returns:

  • (self)


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# File 'dbm.c', line 714

static VALUE
fdbm_each_value(VALUE obj)
{
    datum key, val;
    struct dbmdata *dbmp;
    DBM *dbm;

    RETURN_ENUMERATOR(obj, 0, 0);

    GetDBM2(obj, dbmp, dbm);
    for (key = dbm_firstkey(dbm); key.dptr; key = dbm_nextkey(dbm)) {
	val = dbm_fetch(dbm, key);
	rb_yield(rb_tainted_str_new(val.dptr, val.dsize));
	GetDBM2(obj, dbmp, dbm);
    }
    return obj;
}

#empty?Boolean

Returns true if the database is empty, false otherwise.

Returns:

  • (Boolean)


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# File 'dbm.c', line 686

static VALUE
fdbm_empty_p(VALUE obj)
{
    datum key;
    struct dbmdata *dbmp;
    DBM *dbm;

    GetDBM2(obj, dbmp, dbm);
    if (dbmp->di_size < 0) {
	dbm = dbmp->di_dbm;

	for (key = dbm_firstkey(dbm); key.dptr; key = dbm_nextkey(dbm)) {
	    return Qfalse;
	}
    }
    else {
	if (dbmp->di_size)
	    return Qfalse;
    }
    return Qtrue;
}

#fetch(key[, ifnone]) ⇒ Object

Return a value from the database by locating the key string provided. If the key is not found, returns ifnone. If ifnone is not given, raises IndexError.



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# File 'dbm.c', line 290

static VALUE
fdbm_fetch_m(int argc, VALUE *argv, VALUE obj)
{
    VALUE keystr, valstr, ifnone;

    rb_scan_args(argc, argv, "11", &keystr, &ifnone);
    valstr = fdbm_fetch(obj, keystr, ifnone);
    if (argc == 1 && !rb_block_given_p() && NIL_P(valstr))
	rb_raise(rb_eIndexError, "key not found");

    return valstr;
}

#has_key?(key) ⇒ Boolean

Returns true if the database contains the specified key, false otherwise.

Returns:

  • (Boolean)

Returns:

  • (Boolean)


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# File 'dbm.c', line 839

static VALUE
fdbm_has_key(VALUE obj, VALUE keystr)
{
    datum key, val;
    struct dbmdata *dbmp;
    DBM *dbm;
    long len;

    ExportStringValue(keystr);
    len = RSTRING_LEN(keystr);
    if (TOO_LONG(len)) return Qfalse;
    key.dptr = RSTRING_PTR(keystr);
    key.dsize = (DSIZE_TYPE)len;

    GetDBM2(obj, dbmp, dbm);
    val = dbm_fetch(dbm, key);
    if (val.dptr) return Qtrue;
    return Qfalse;
}

#has_value?(value) ⇒ Boolean

Returns true if the database contains the specified string value, false otherwise.

Returns:

  • (Boolean)

Returns:

  • (Boolean)


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# File 'dbm.c', line 866

static VALUE
fdbm_has_value(VALUE obj, VALUE valstr)
{
    datum key, val;
    struct dbmdata *dbmp;
    DBM *dbm;
    long len;

    ExportStringValue(valstr);
    len = RSTRING_LEN(valstr);
    if (TOO_LONG(len)) return Qfalse;
    val.dptr = RSTRING_PTR(valstr);
    val.dsize = (DSIZE_TYPE)len;

    GetDBM2(obj, dbmp, dbm);
    for (key = dbm_firstkey(dbm); key.dptr; key = dbm_nextkey(dbm)) {
	val = dbm_fetch(dbm, key);
	if ((DSIZE_TYPE)val.dsize == (DSIZE_TYPE)RSTRING_LEN(valstr) &&
	    memcmp(val.dptr, RSTRING_PTR(valstr), val.dsize) == 0)
	    return Qtrue;
    }
    return Qfalse;
}

#has_key?(key) ⇒ Boolean

Returns true if the database contains the specified key, false otherwise.

Returns:

  • (Boolean)

Returns:

  • (Boolean)


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# File 'dbm.c', line 839

static VALUE
fdbm_has_key(VALUE obj, VALUE keystr)
{
    datum key, val;
    struct dbmdata *dbmp;
    DBM *dbm;
    long len;

    ExportStringValue(keystr);
    len = RSTRING_LEN(keystr);
    if (TOO_LONG(len)) return Qfalse;
    key.dptr = RSTRING_PTR(keystr);
    key.dsize = (DSIZE_TYPE)len;

    GetDBM2(obj, dbmp, dbm);
    val = dbm_fetch(dbm, key);
    if (val.dptr) return Qtrue;
    return Qfalse;
}

#indexObject

:nodoc:



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# File 'dbm.c', line 335

static VALUE
fdbm_index(VALUE hash, VALUE value)
{
    rb_warn("DBM#index is deprecated; use DBM#key");
    return fdbm_key(hash, value);
}

#invertHash

Returns a Hash (not a DBM database) created by using each value in the database as a key, with the corresponding key as its value.

Returns:

  • (Hash)


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# File 'dbm.c', line 556

static VALUE
fdbm_invert(VALUE obj)
{
    datum key, val;
    struct dbmdata *dbmp;
    DBM *dbm;
    VALUE keystr, valstr;
    VALUE hash = rb_hash_new();

    GetDBM2(obj, dbmp, dbm);
    for (key = dbm_firstkey(dbm); key.dptr; key = dbm_nextkey(dbm)) {
	val = dbm_fetch(dbm, key);
	keystr = rb_tainted_str_new(key.dptr, key.dsize);
	valstr = rb_tainted_str_new(val.dptr, val.dsize);
	rb_hash_aset(hash, valstr, keystr);
    }
    return hash;
}

#key(value) ⇒ String

Returns the key for the specified value.

Returns:

  • (String)


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# File 'dbm.c', line 309

static VALUE
fdbm_key(VALUE obj, VALUE valstr)
{
    datum key, val;
    struct dbmdata *dbmp;
    DBM *dbm;
    long len;

    ExportStringValue(valstr);
    len = RSTRING_LEN(valstr);
    if (TOO_LONG(len)) return Qnil;
    val.dptr = RSTRING_PTR(valstr);
    val.dsize = (DSIZE_TYPE)len;

    GetDBM2(obj, dbmp, dbm);
    for (key = dbm_firstkey(dbm); key.dptr; key = dbm_nextkey(dbm)) {
	val = dbm_fetch(dbm, key);
	if ((long)val.dsize == RSTRING_LEN(valstr) &&
	    memcmp(val.dptr, RSTRING_PTR(valstr), val.dsize) == 0) {
	    return rb_tainted_str_new(key.dptr, key.dsize);
	}
    }
    return Qnil;
}

#has_key?(key) ⇒ Boolean

Returns true if the database contains the specified key, false otherwise.

Returns:

  • (Boolean)

Returns:

  • (Boolean)


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# File 'dbm.c', line 839

static VALUE
fdbm_has_key(VALUE obj, VALUE keystr)
{
    datum key, val;
    struct dbmdata *dbmp;
    DBM *dbm;
    long len;

    ExportStringValue(keystr);
    len = RSTRING_LEN(keystr);
    if (TOO_LONG(len)) return Qfalse;
    key.dptr = RSTRING_PTR(keystr);
    key.dsize = (DSIZE_TYPE)len;

    GetDBM2(obj, dbmp, dbm);
    val = dbm_fetch(dbm, key);
    if (val.dptr) return Qtrue;
    return Qfalse;
}

#keysArray

Returns an array of all the string keys in the database.

Returns:

  • (Array)


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# File 'dbm.c', line 791

static VALUE
fdbm_keys(VALUE obj)
{
    datum key;
    struct dbmdata *dbmp;
    DBM *dbm;
    VALUE ary;

    GetDBM2(obj, dbmp, dbm);

    ary = rb_ary_new();
    for (key = dbm_firstkey(dbm); key.dptr; key = dbm_nextkey(dbm)) {
	rb_ary_push(ary, rb_tainted_str_new(key.dptr, key.dsize));
    }

    return ary;
}

#lengthInteger

Returns the number of entries in the database.

Returns:

  • (Integer)


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# File 'dbm.c', line 661

static VALUE
fdbm_length(VALUE obj)
{
    datum key;
    struct dbmdata *dbmp;
    DBM *dbm;
    int i = 0;

    GetDBM2(obj, dbmp, dbm);
    if (dbmp->di_size > 0) return INT2FIX(dbmp->di_size);

    for (key = dbm_firstkey(dbm); key.dptr; key = dbm_nextkey(dbm)) {
	i++;
    }
    dbmp->di_size = i;

    return INT2FIX(i);
}

#has_key?(key) ⇒ Boolean

Returns true if the database contains the specified key, false otherwise.

Returns:

  • (Boolean)

Returns:

  • (Boolean)


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# File 'dbm.c', line 839

static VALUE
fdbm_has_key(VALUE obj, VALUE keystr)
{
    datum key, val;
    struct dbmdata *dbmp;
    DBM *dbm;
    long len;

    ExportStringValue(keystr);
    len = RSTRING_LEN(keystr);
    if (TOO_LONG(len)) return Qfalse;
    key.dptr = RSTRING_PTR(keystr);
    key.dsize = (DSIZE_TYPE)len;

    GetDBM2(obj, dbmp, dbm);
    val = dbm_fetch(dbm, key);
    if (val.dptr) return Qtrue;
    return Qfalse;
}

#reject {|key, value| ... } ⇒ Hash

Converts the contents of the database to an in-memory Hash, then calls Hash#reject with the specified code block, returning a new Hash.

Yields:

Returns:

  • (Hash)


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# File 'dbm.c', line 949

static VALUE
fdbm_reject(VALUE obj)
{
    return rb_hash_delete_if(fdbm_to_hash(obj));
}

#reject! {|key, value| ... } ⇒ self #delete_if {|key, value| ... } ⇒ self

Deletes all entries for which the code block returns true. Returns self.

Overloads:

  • #reject! {|key, value| ... } ⇒ self

    Yields:

    Returns:

    • (self)
  • #delete_if {|key, value| ... } ⇒ self

    Yields:

    Returns:

    • (self)


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# File 'dbm.c', line 481

static VALUE
fdbm_delete_if(VALUE obj)
{
    datum key, val;
    struct dbmdata *dbmp;
    DBM *dbm;
    VALUE keystr, valstr;
    VALUE ret, ary = rb_ary_tmp_new(0);
    int i, status = 0;
    long n;

    fdbm_modify(obj);
    GetDBM2(obj, dbmp, dbm);
    n = dbmp->di_size;
    dbmp->di_size = -1;

    for (key = dbm_firstkey(dbm); key.dptr; key = dbm_nextkey(dbm)) {
	val = dbm_fetch(dbm, key);
	keystr = rb_tainted_str_new(key.dptr, key.dsize);
	OBJ_FREEZE(keystr);
	valstr = rb_tainted_str_new(val.dptr, val.dsize);
        ret = rb_protect(rb_yield, rb_assoc_new(rb_str_dup(keystr), valstr), &status);
        if (status != 0) break;
	if (RTEST(ret)) rb_ary_push(ary, keystr);
	GetDBM2(obj, dbmp, dbm);
    }

    for (i = 0; i < RARRAY_LEN(ary); i++) {
	keystr = RARRAY_PTR(ary)[i];
	key.dptr = RSTRING_PTR(keystr);
	key.dsize = (DSIZE_TYPE)RSTRING_LEN(keystr);
	if (dbm_delete(dbm, key)) {
	    rb_raise(rb_eDBMError, "dbm_delete failed");
	}
    }
    if (status) rb_jump_tag(status);
    if (n > 0) dbmp->di_size = n - RARRAY_LEN(ary);
    rb_ary_clear(ary);

    return obj;
}

#replace(obj) ⇒ Object

Replaces the contents of the database with the contents of the specified object. Takes any object which implements the each_pair method, including Hash and DBM objects.



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# File 'dbm.c', line 611

static VALUE
fdbm_replace(VALUE obj, VALUE other)
{
    fdbm_clear(obj);
    rb_block_call(other, rb_intern("each_pair"), 0, 0, update_i, obj);
    return obj;
}

#select {|key, value| ... } ⇒ Array

Returns a new array consisting of the [key, value] pairs for which the code block returns true.

Yields:

Returns:

  • (Array)


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# File 'dbm.c', line 349

static VALUE
fdbm_select(VALUE obj)
{
    VALUE new = rb_ary_new();
    datum key, val;
    DBM *dbm;
    struct dbmdata *dbmp;

    GetDBM2(obj, dbmp, dbm);
    for (key = dbm_firstkey(dbm); key.dptr; key = dbm_nextkey(dbm)) {
	VALUE assoc, v;
	val = dbm_fetch(dbm, key);
	assoc = rb_assoc_new(rb_tainted_str_new(key.dptr, key.dsize),
			     rb_tainted_str_new(val.dptr, val.dsize));
	v = rb_yield(assoc);
	if (RTEST(v)) {
	    rb_ary_push(new, assoc);
	}
	GetDBM2(obj, dbmp, dbm);
    }

    return new;
}

#shiftArray

Removes a [key, value] pair from the database, and returns it. If the database is empty, returns nil. The order in which values are removed/returned is not guaranteed.

Returns:

  • (Array)


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# File 'dbm.c', line 451

static VALUE
fdbm_shift(VALUE obj)
{
    datum key, val;
    struct dbmdata *dbmp;
    DBM *dbm;
    VALUE keystr, valstr;

    fdbm_modify(obj);
    GetDBM2(obj, dbmp, dbm);
    dbmp->di_size = -1;

    key = dbm_firstkey(dbm);
    if (!key.dptr) return Qnil;
    val = dbm_fetch(dbm, key);
    keystr = rb_tainted_str_new(key.dptr, key.dsize);
    valstr = rb_tainted_str_new(val.dptr, val.dsize);
    dbm_delete(dbm, key);

    return rb_assoc_new(keystr, valstr);
}

#lengthInteger

Returns the number of entries in the database.

Returns:

  • (Integer)


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# File 'dbm.c', line 661

static VALUE
fdbm_length(VALUE obj)
{
    datum key;
    struct dbmdata *dbmp;
    DBM *dbm;
    int i = 0;

    GetDBM2(obj, dbmp, dbm);
    if (dbmp->di_size > 0) return INT2FIX(dbmp->di_size);

    for (key = dbm_firstkey(dbm); key.dptr; key = dbm_nextkey(dbm)) {
	i++;
    }
    dbmp->di_size = i;

    return INT2FIX(i);
}

#store(key, value) ⇒ Object #[]=(key) ⇒ Object

Stores the specified string value in the database, indexed via the string key provided.



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# File 'dbm.c', line 627

static VALUE
fdbm_store(VALUE obj, VALUE keystr, VALUE valstr)
{
    datum key, val;
    struct dbmdata *dbmp;
    DBM *dbm;

    fdbm_modify(obj);
    keystr = rb_obj_as_string(keystr);
    valstr = rb_obj_as_string(valstr);

    key.dptr = RSTRING_PTR(keystr);
    key.dsize = RSTRING_DSIZE(keystr);

    val.dptr = RSTRING_PTR(valstr);
    val.dsize = RSTRING_DSIZE(valstr);

    GetDBM2(obj, dbmp, dbm);
    dbmp->di_size = -1;
    if (dbm_store(dbm, key, val, DBM_REPLACE)) {
	dbm_clearerr(dbm);
	if (errno == EPERM) rb_sys_fail(0);
	rb_raise(rb_eDBMError, "dbm_store failed");
    }

    return valstr;
}

#to_aArray

Converts the contents of the database to an array of [key, value] arrays, and returns it.

Returns:

  • (Array)


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# File 'dbm.c', line 897

static VALUE
fdbm_to_a(VALUE obj)
{
    datum key, val;
    struct dbmdata *dbmp;
    DBM *dbm;
    VALUE ary;

    GetDBM2(obj, dbmp, dbm);
    ary = rb_ary_new();
    for (key = dbm_firstkey(dbm); key.dptr; key = dbm_nextkey(dbm)) {
	val = dbm_fetch(dbm, key);
	rb_ary_push(ary, rb_assoc_new(rb_tainted_str_new(key.dptr, key.dsize),
				      rb_tainted_str_new(val.dptr, val.dsize)));
    }

    return ary;
}

#to_hashHash

Converts the contents of the database to an in-memory Hash object, and returns it.

Returns:

  • (Hash)


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# File 'dbm.c', line 923

static VALUE
fdbm_to_hash(VALUE obj)
{
    datum key, val;
    struct dbmdata *dbmp;
    DBM *dbm;
    VALUE hash;

    GetDBM2(obj, dbmp, dbm);
    hash = rb_hash_new();
    for (key = dbm_firstkey(dbm); key.dptr; key = dbm_nextkey(dbm)) {
	val = dbm_fetch(dbm, key);
	rb_hash_aset(hash, rb_tainted_str_new(key.dptr, key.dsize),
		           rb_tainted_str_new(val.dptr, val.dsize));
    }

    return hash;
}

#update(obj) ⇒ Object

Updates the database with multiple values from the specified object. Takes any object which implements the each_pair method, including Hash and DBM objects.



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# File 'dbm.c', line 596

static VALUE
fdbm_update(VALUE obj, VALUE other)
{
    rb_block_call(other, rb_intern("each_pair"), 0, 0, update_i, obj);
    return obj;
}

#has_value?(value) ⇒ Boolean

Returns true if the database contains the specified string value, false otherwise.

Returns:

  • (Boolean)

Returns:

  • (Boolean)


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# File 'dbm.c', line 866

static VALUE
fdbm_has_value(VALUE obj, VALUE valstr)
{
    datum key, val;
    struct dbmdata *dbmp;
    DBM *dbm;
    long len;

    ExportStringValue(valstr);
    len = RSTRING_LEN(valstr);
    if (TOO_LONG(len)) return Qfalse;
    val.dptr = RSTRING_PTR(valstr);
    val.dsize = (DSIZE_TYPE)len;

    GetDBM2(obj, dbmp, dbm);
    for (key = dbm_firstkey(dbm); key.dptr; key = dbm_nextkey(dbm)) {
	val = dbm_fetch(dbm, key);
	if ((DSIZE_TYPE)val.dsize == (DSIZE_TYPE)RSTRING_LEN(valstr) &&
	    memcmp(val.dptr, RSTRING_PTR(valstr), val.dsize) == 0)
	    return Qtrue;
    }
    return Qfalse;
}

#valuesArray

Returns an array of all the string values in the database.

Returns:

  • (Array)


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# File 'dbm.c', line 815

static VALUE
fdbm_values(VALUE obj)
{
    datum key, val;
    struct dbmdata *dbmp;
    DBM *dbm;
    VALUE ary;

    GetDBM2(obj, dbmp, dbm);
    ary = rb_ary_new();
    for (key = dbm_firstkey(dbm); key.dptr; key = dbm_nextkey(dbm)) {
	val = dbm_fetch(dbm, key);
	rb_ary_push(ary, rb_tainted_str_new(val.dptr, val.dsize));
    }

    return ary;
}

#values_at(key, ...) ⇒ Array

Returns an array containing the values associated with the given keys.

Returns:

  • (Array)


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# File 'dbm.c', line 379

static VALUE
fdbm_values_at(int argc, VALUE *argv, VALUE obj)
{
    VALUE new = rb_ary_new2(argc);
    int i;

    for (i=0; i<argc; i++) {
        rb_ary_push(new, fdbm_fetch(obj, argv[i], Qnil));
    }

    return new;
}