Module: MmappedString

Defined in:
lib/mmapped_string.rb,
lib/mmapped_string/version.rb,
ext/mmapped_string/mmapped_string.c

Constant Summary collapse

VERSION = 
"0.1.0"

Class Method Summary collapse

Class Method Details

.mmap_open(fname, lengthv) ⇒ Object 



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# File 'ext/mmapped_string/mmapped_string.c', line 36

static VALUE
mmap_open(VALUE self, VALUE fname, VALUE lengthv)
{
    struct mmap_data *data;
    VALUE data_val, str;
    data_val = TypedData_Make_Struct(0, struct mmap_data, &mmap_data_type, data);

    data->length = NUM2SIZET(lengthv);
    data->fd = open(StringValueCStr(fname), O_RDONLY);
    if (data->fd == -1) rb_sys_fail("open");

    data->addr = mmap(NULL, data->length, PROT_READ, MAP_PRIVATE, data->fd, 0);
    if (data->addr == MAP_FAILED) rb_sys_fail("mmap");

    if (madvise(data->addr, data->length, MADV_RANDOM) == -1) rb_sys_fail("madvise");

    data->opened = 1;

    str = rb_str_new_static(data->addr, data->length);
    rb_ivar_set(str, rb_intern("mmap_data"), data_val);

    return rb_obj_freeze(str);
}

.open(fname) ⇒ Object 



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# File 'lib/mmapped_string.rb', line 5

def self.open fname
  mmap_open(fname, File.size(fname))
end