djsundog/circuitpython
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

extmod/moduzlib: Fix parsing zlib header dict size.

Browse Source 
From RFC 1950 section 2.2: "CINFO is the base-2 logarithm of the LZ77
window size, minus eight (CINFO=7 indicates a 32K window size)"

Signed-off-by: Daniël van de Giessen <daniel@dvdgiessen.nl>
This commit is contained in:
Daniël van de Giessen 2020-08-27 14:16:48 +02:00 committed by Damien George
parent e0b97013d0
commit e2513bfe8d
1 changed files with 6 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
extmod/moduzlib.c
View File

@ -77,7 +77,7 @@ STATIC mp_obj_t decompio_make_new(const mp_obj_type_t *type, size_t n_args, size
o->eof = false;
mp_int_t dict_opt = 0;
int dict_sz;
uint dict_sz;
if (n_args > 1) {
dict_opt = mp_obj_get_int(args[1]);
}
@ -94,7 +94,10 @@ STATIC mp_obj_t decompio_make_new(const mp_obj_type_t *type, size_t n_args, size
header_error:
mp_raise_ValueError(MP_ERROR_TEXT("compression header"));
}
dict_sz = 1 << dict_opt;
// RFC 1950 section 2.2:
// CINFO is the base-2 logarithm of the LZ77 window size,
// minus eight (CINFO=7 indicates a 32K window size)
dict_sz = 1 << (dict_opt + 8);
} else {
dict_sz = 1 << -dict_opt;
}
@ -116,6 +119,7 @@ STATIC mp_uint_t decompio_read(mp_obj_t o_in, void *buf, mp_uint_t size, int *er
o->eof = true;
}
if (st < 0) {
DEBUG_printf("uncompress error=" INT_FMT "\n", st);
*errcode = MP_EINVAL;
return MP_STREAM_ERROR;
}