Commit 57a4b4f1 authored by Damien George's avatar Damien George
Browse files

py: Add typecode to buffer protocol.

When querying an object that supports the buffer protocol, that object
must now return a typecode (as per binary.[ch]).  This does not have to
be honoured by the caller, but can be useful for determining element
size.
parent 3fd2d7fa
......@@ -55,7 +55,7 @@ STATIC mp_obj_t struct_unpack(mp_obj_t fmt_in, mp_obj_t data_in) {
char fmt_type = get_fmt_type(&fmt);
uint size = calcsize_items(fmt);
mp_obj_tuple_t *res = mp_obj_new_tuple(size, NULL);
buffer_info_t bufinfo;
mp_buffer_info_t bufinfo;
mp_get_buffer_raise(data_in, &bufinfo);
byte *p = bufinfo.buf;
......
......@@ -357,20 +357,20 @@ mp_obj_t mp_identity(mp_obj_t self) {
}
MP_DEFINE_CONST_FUN_OBJ_1(mp_identity_obj, mp_identity);
bool mp_get_buffer(mp_obj_t obj, buffer_info_t *bufinfo) {
bool mp_get_buffer(mp_obj_t obj, mp_buffer_info_t *bufinfo) {
mp_obj_type_t *type = mp_obj_get_type(obj);
if (type->buffer_p.get_buffer == NULL) {
return false;
}
type->buffer_p.get_buffer(obj, bufinfo, BUFFER_READ);
if (bufinfo->buf == NULL) {
int ret = type->buffer_p.get_buffer(obj, bufinfo, MP_BUFFER_READ);
if (ret != 0 || bufinfo->buf == NULL) {
return false;
}
return true;
}
void mp_get_buffer_raise(mp_obj_t obj, buffer_info_t *bufinfo) {
void mp_get_buffer_raise(mp_obj_t obj, mp_buffer_info_t *bufinfo) {
if (!mp_get_buffer(obj, bufinfo)) {
nlr_raise(mp_obj_new_exception_msg(&mp_type_TypeError, "Object with buffer protocol required"));
nlr_raise(mp_obj_new_exception_msg(&mp_type_TypeError, "object with buffer protocol required"));
}
}
......@@ -189,32 +189,28 @@ typedef struct _mp_method_t {
} mp_method_t;
// Buffer protocol
typedef struct _buffer_info_t {
typedef struct _mp_buffer_info_t {
// if we'd bother to support various versions of structure
// (with different number of fields), we can distinguish
// them with ver = sizeof(struct). Cons: overkill for *micro*?
//int ver; // ?
void *buf;
machine_int_t len;
// Rationale: have array.array and have SIMD operations on them
// Cons: users can pass item size to processing functions themselves,
// though that's not "plug&play"
// int itemsize;
machine_int_t len; // in bytes
int typecode; // as per binary.h
// Rationale: to load arbitrary-sized sprites directly to LCD
// Cons: a bit adhoc usecase
// int stride;
} buffer_info_t;
#define BUFFER_READ (1)
#define BUFFER_WRITE (2)
#define BUFFER_RW (BUFFER_READ | BUFFER_WRITE)
} mp_buffer_info_t;
#define MP_BUFFER_READ (1)
#define MP_BUFFER_WRITE (2)
#define MP_BUFFER_RW (MP_BUFFER_READ | MP_BUFFER_WRITE)
typedef struct _mp_buffer_p_t {
machine_int_t (*get_buffer)(mp_obj_t obj, buffer_info_t *bufinfo, int flags);
machine_int_t (*get_buffer)(mp_obj_t obj, mp_buffer_info_t *bufinfo, int flags);
} mp_buffer_p_t;
bool mp_get_buffer(mp_obj_t obj, buffer_info_t *bufinfo);
void mp_get_buffer_raise(mp_obj_t obj, buffer_info_t *bufinfo);
bool mp_get_buffer(mp_obj_t obj, mp_buffer_info_t *bufinfo);
void mp_get_buffer_raise(mp_obj_t obj, mp_buffer_info_t *bufinfo);
// Stream protocol
typedef struct _mp_stream_p_t {
......
......@@ -151,10 +151,11 @@ STATIC mp_obj_t array_subscr(mp_obj_t self_in, mp_obj_t index_in, mp_obj_t value
}
}
STATIC machine_int_t array_get_buffer(mp_obj_t o_in, buffer_info_t *bufinfo, int flags) {
STATIC machine_int_t array_get_buffer(mp_obj_t o_in, mp_buffer_info_t *bufinfo, int flags) {
mp_obj_array_t *o = o_in;
bufinfo->buf = o->items;
bufinfo->len = o->len * mp_binary_get_size(o->typecode);
bufinfo->typecode = o->typecode;
return 0;
}
......
......@@ -426,7 +426,7 @@ STATIC machine_uint_t convert_obj_for_inline_asm(mp_obj_t obj) {
mp_obj_list_get(obj, &len, &items);
return (machine_uint_t)items;
} else {
buffer_info_t bufinfo;
mp_buffer_info_t bufinfo;
if (mp_get_buffer(obj, &bufinfo)) {
// supports the buffer protocol, return a pointer to the data
return (machine_uint_t)bufinfo.buf;
......
......@@ -272,7 +272,7 @@ STATIC mp_obj_t int_from_bytes(uint n_args, const mp_obj_t *args) {
// TODO: Support signed param (assumes signed=False at the moment)
// get the buffer info
buffer_info_t bufinfo;
mp_buffer_info_t bufinfo;
mp_get_buffer_raise(args[1], &bufinfo);
// convert the bytes to an integer
......
......@@ -1326,16 +1326,18 @@ STATIC mp_obj_t str_encode(uint n_args, const mp_obj_t *args) {
}
#endif
STATIC machine_int_t str_get_buffer(mp_obj_t self_in, buffer_info_t *bufinfo, int flags) {
if (flags == BUFFER_READ) {
STATIC machine_int_t str_get_buffer(mp_obj_t self_in, mp_buffer_info_t *bufinfo, int flags) {
if (flags == MP_BUFFER_READ) {
GET_STR_DATA_LEN(self_in, str_data, str_len);
bufinfo->buf = (void*)str_data;
bufinfo->len = str_len;
bufinfo->typecode = 'b';
return 0;
} else {
// can't write to a string
bufinfo->buf = NULL;
bufinfo->len = 0;
bufinfo->typecode = -1;
return 1;
}
}
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment