def get_raw_address_of_string(space, w_x):
"""Special case for ffi.from_buffer(string). Returns a 'char *' that
is valid as long as the string object is alive. Two calls to
ffi.from_buffer(same_string) are guaranteed to return the same pointer.
"""
from rpython.rtyper.annlowlevel import llstr
from rpython.rtyper.lltypesystem.rstr import STR
from rpython.rtyper.lltypesystem import llmemory
from rpython.rlib import rgc
cache = space.fromcache(RawBytesCache)
rawbytes = cache.wdict.get(w_x)
if rawbytes is None:
data = space.bytes_w(w_x)
if (we_are_translated() and not rgc.can_move(data)
and not rgc.must_split_gc_address_space()):
lldata = llstr(data)
data_start = (llmemory.cast_ptr_to_adr(lldata) +
rffi.offsetof(STR, 'chars') +
llmemory.itemoffsetof(STR.chars, 0))
data_start = rffi.cast(rffi.CCHARP, data_start)
data_start[len(data)] = '\x00' # write the final extra null
return data_start
rawbytes = RawBytes(data)
cache.wdict.set(w_x, rawbytes)
return rawbytes.ptr
def copy_string_contents(src, dst, srcstart, dststart, length):
"""Copies 'length' characters from the 'src' string to the 'dst'
string, starting at position 'srcstart' and 'dststart'."""
# xxx Warning: don't try to do this at home. It relies on a lot
# of details to be sure that it works correctly in all cases.
# Notably: no GC operation at all from the first cast_ptr_to_adr()
# because it might move the strings. The keepalive_until_here()
# are obscurely essential to make sure that the strings stay alive
# longer than the raw_memcopy().
assert length >= 0
ll_assert(srcstart >= 0, "copystrc: negative srcstart")
ll_assert(srcstart + length <= len(src.chars), "copystrc: src ovf")
ll_assert(dststart >= 0, "copystrc: negative dststart")
ll_assert(dststart + length <= len(dst.chars), "copystrc: dst ovf")
#
# If the 'split_gc_address_space' option is set, we must copy
# manually, character-by-character
if rgc.must_split_gc_address_space():
i = 0
while i < length:
dst.chars[dststart + i] = src.chars[srcstart + i]
i += 1
return
#
#
# from here, no GC operations can happen
asrc = _get_raw_buf(SRC_TP, src, srcstart)
adst = _get_raw_buf(DST_TP, dst, dststart)
llmemory.raw_memcopy(asrc, adst, llmemory.sizeof(CHAR_TP) * length)
# end of "no GC" section
keepalive_until_here(src)
keepalive_until_here(dst)
def copy_string_to_raw(src, ptrdst, srcstart, length):
"""
Copies 'length' characters from the 'src' string to the 'ptrdst'
buffer, starting at position 'srcstart'.
'ptrdst' must be a non-gc Array of Char.
"""
# xxx Warning: same note as above apply: don't do this at home
assert length >= 0
#
# If the 'split_gc_address_space' option is set, we must copy
# manually, character-by-character
if rgc.must_split_gc_address_space():
i = 0
while i < length:
ptrdst[i] = src.chars[srcstart + i]
i += 1
return
#
# from here, no GC operations can happen
asrc = _get_raw_buf(SRC_TP, src, srcstart)
adst = llmemory.cast_ptr_to_adr(ptrdst)
adst = adst + llmemory.itemoffsetof(typeOf(ptrdst).TO, 0)
llmemory.raw_memcopy(asrc, adst, llmemory.sizeof(CHAR_TP) * length)
# end of "no GC" section
keepalive_until_here(src)
def ll_string2list(RESLIST, src):
length = len(src.chars)
lst = RESLIST.ll_newlist(length)
dst = lst.ll_items()
SRC = typeOf(src).TO # STR or UNICODE
DST = typeOf(dst).TO # GcArray
assert DST.OF is SRC.chars.OF
#
# If the 'split_gc_address_space' option is set, we must copy
# manually, character-by-character
if rgc.must_split_gc_address_space():
i = 0
while i < length:
dst[i] = src.chars[i]
i += 1
return lst
#
# from here, no GC operations can happen
asrc = llmemory.cast_ptr_to_adr(src) + (llmemory.offsetof(
SRC, 'chars') + llmemory.itemoffsetof(SRC.chars, 0))
adst = llmemory.cast_ptr_to_adr(dst) + llmemory.itemoffsetof(DST, 0)
llmemory.raw_memcopy(asrc, adst, llmemory.sizeof(DST.OF) * length)
# end of "no GC" section
keepalive_until_here(src)
keepalive_until_here(dst)
return lst
def ll_populate_list_from_raw_array(ll_list, src_ptr, length):
ll_list._ll_resize(length)
if rgc.must_split_gc_address_space():
for i in range(length):
ll_list.ll_setitem_fast(i, src_ptr[i])
return
ITEM = lltype.typeOf(src_ptr).TO.OF
size = llmemory.sizeof(ITEM) * length
# start of no-GC section
src_adr = get_raw_buf(src_ptr)
dst_adr = get_raw_buf(ll_list.ll_items())
llmemory.raw_memcopy(src_adr, dst_adr, size)
def ll_copy_list_to_raw_array(ll_list, dst_ptr):
if rgc.must_split_gc_address_space():
for i in range(ll_list.ll_length()):
dst_ptr[i] = ll_list.ll_getitem_fast(i)
return
# this code is delicate: we must ensure that there are no GC operations
# around the call to raw_memcopy
#
ITEM = lltype.typeOf(dst_ptr).TO.OF
size = llmemory.sizeof(ITEM) * ll_list.ll_length()
# start of no-GC section
src_adr = get_raw_buf(ll_list.ll_items())
dst_adr = get_raw_buf(dst_ptr)
llmemory.raw_memcopy(src_adr, dst_adr, size)
def copy_raw_to_string(ptrsrc, dst, dststart, length):
# xxx Warning: same note as above apply: don't do this at home
assert length >= 0
#
# If the 'split_gc_address_space' option is set, we must copy
# manually, character-by-character
if rgc.must_split_gc_address_space():
i = 0
while i < length:
dst.chars[dststart + i] = ptrsrc[i]
i += 1
return
#
# from here, no GC operations can happen
adst = _get_raw_buf(SRC_TP, dst, dststart)
asrc = llmemory.cast_ptr_to_adr(ptrsrc)
asrc = asrc + llmemory.itemoffsetof(typeOf(ptrsrc).TO, 0)
llmemory.raw_memcopy(asrc, adst, llmemory.sizeof(CHAR_TP) * length)
# end of "no GC" section
keepalive_until_here(dst)
def hide_reveal():
if rgc.must_split_gc_address_space():
return hide_reveal_slow
else:
return hide_reveal_fast