Issue #14596: The struct.Struct() objects now use more compact implementation.
diff --git a/Modules/_struct.c b/Modules/_struct.c
index 2dec4ed..5848b19 100644
--- a/Modules/_struct.c
+++ b/Modules/_struct.c
@@ -26,6 +26,7 @@
const struct _formatdef *fmtdef;
Py_ssize_t offset;
Py_ssize_t size;
+ Py_ssize_t repeat;
} formatcode;
/* Struct object interface */
@@ -1263,7 +1264,7 @@
const char *s;
const char *fmt;
char c;
- Py_ssize_t size, len, num, itemsize;
+ Py_ssize_t size, len, ncodes, num, itemsize;
fmt = PyBytes_AS_STRING(self->s_format);
@@ -1272,6 +1273,7 @@
s = fmt;
size = 0;
len = 0;
+ ncodes = 0;
while ((c = *s++) != '\0') {
if (Py_ISSPACE(Py_CHARMASK(c)))
continue;
@@ -1301,9 +1303,9 @@
switch (c) {
case 's': /* fall through */
- case 'p': len++; break;
+ case 'p': len++; ncodes++; break;
case 'x': break;
- default: len += num; break;
+ default: len += num; if (num) ncodes++; break;
}
itemsize = e->size;
@@ -1318,14 +1320,14 @@
}
/* check for overflow */
- if ((len + 1) > (PY_SSIZE_T_MAX / sizeof(formatcode))) {
+ if ((ncodes + 1) > (PY_SSIZE_T_MAX / sizeof(formatcode))) {
PyErr_NoMemory();
return -1;
}
self->s_size = size;
self->s_len = len;
- codes = PyMem_MALLOC((len + 1) * sizeof(formatcode));
+ codes = PyMem_MALLOC((ncodes + 1) * sizeof(formatcode));
if (codes == NULL) {
PyErr_NoMemory();
return -1;
@@ -1357,23 +1359,24 @@
codes->offset = size;
codes->size = num;
codes->fmtdef = e;
+ codes->repeat = 1;
codes++;
size += num;
} else if (c == 'x') {
size += num;
- } else {
- while (--num >= 0) {
- codes->offset = size;
- codes->size = e->size;
- codes->fmtdef = e;
- codes++;
- size += e->size;
- }
+ } else if (num) {
+ codes->offset = size;
+ codes->size = e->size;
+ codes->fmtdef = e;
+ codes->repeat = num;
+ codes++;
+ size += e->size * num;
}
}
codes->fmtdef = NULL;
codes->offset = size;
codes->size = 0;
+ codes->repeat = 0;
return 0;
@@ -1462,22 +1465,26 @@
return NULL;
for (code = soself->s_codes; code->fmtdef != NULL; code++) {
- PyObject *v;
const formatdef *e = code->fmtdef;
const char *res = startfrom + code->offset;
- if (e->format == 's') {
- v = PyBytes_FromStringAndSize(res, code->size);
- } else if (e->format == 'p') {
- Py_ssize_t n = *(unsigned char*)res;
- if (n >= code->size)
- n = code->size - 1;
- v = PyBytes_FromStringAndSize(res + 1, n);
- } else {
- v = e->unpack(res, e);
+ Py_ssize_t j = code->repeat;
+ while (j--) {
+ PyObject *v;
+ if (e->format == 's') {
+ v = PyBytes_FromStringAndSize(res, code->size);
+ } else if (e->format == 'p') {
+ Py_ssize_t n = *(unsigned char*)res;
+ if (n >= code->size)
+ n = code->size - 1;
+ v = PyBytes_FromStringAndSize(res + 1, n);
+ } else {
+ v = e->unpack(res, e);
+ }
+ if (v == NULL)
+ goto fail;
+ PyTuple_SET_ITEM(result, i++, v);
+ res += code->size;
}
- if (v == NULL)
- goto fail;
- PyTuple_SET_ITEM(result, i++, v);
}
return result;
@@ -1716,62 +1723,67 @@
memset(buf, '\0', soself->s_size);
i = offset;
for (code = soself->s_codes; code->fmtdef != NULL; code++) {
- Py_ssize_t n;
- PyObject *v = PyTuple_GET_ITEM(args, i++);
const formatdef *e = code->fmtdef;
char *res = buf + code->offset;
- if (e->format == 's') {
- int isstring;
- void *p;
- isstring = PyBytes_Check(v);
- if (!isstring && !PyByteArray_Check(v)) {
- PyErr_SetString(StructError,
- "argument for 's' must be a bytes object");
- return -1;
- }
- if (isstring) {
- n = PyBytes_GET_SIZE(v);
- p = PyBytes_AS_STRING(v);
- }
- else {
- n = PyByteArray_GET_SIZE(v);
- p = PyByteArray_AS_STRING(v);
- }
- if (n > code->size)
- n = code->size;
- if (n > 0)
- memcpy(res, p, n);
- } else if (e->format == 'p') {
- int isstring;
- void *p;
- isstring = PyBytes_Check(v);
- if (!isstring && !PyByteArray_Check(v)) {
- PyErr_SetString(StructError,
- "argument for 'p' must be a bytes object");
- return -1;
- }
- if (isstring) {
- n = PyBytes_GET_SIZE(v);
- p = PyBytes_AS_STRING(v);
- }
- else {
- n = PyByteArray_GET_SIZE(v);
- p = PyByteArray_AS_STRING(v);
- }
- if (n > (code->size - 1))
- n = code->size - 1;
- if (n > 0)
- memcpy(res + 1, p, n);
- if (n > 255)
- n = 255;
- *res = Py_SAFE_DOWNCAST(n, Py_ssize_t, unsigned char);
- } else {
- if (e->pack(res, v, e) < 0) {
- if (PyLong_Check(v) && PyErr_ExceptionMatches(PyExc_OverflowError))
+ Py_ssize_t j = code->repeat;
+ while (j--) {
+ PyObject *v = PyTuple_GET_ITEM(args, i++);
+ if (e->format == 's') {
+ Py_ssize_t n;
+ int isstring;
+ void *p;
+ isstring = PyBytes_Check(v);
+ if (!isstring && !PyByteArray_Check(v)) {
PyErr_SetString(StructError,
- "long too large to convert to int");
- return -1;
+ "argument for 's' must be a bytes object");
+ return -1;
+ }
+ if (isstring) {
+ n = PyBytes_GET_SIZE(v);
+ p = PyBytes_AS_STRING(v);
+ }
+ else {
+ n = PyByteArray_GET_SIZE(v);
+ p = PyByteArray_AS_STRING(v);
+ }
+ if (n > code->size)
+ n = code->size;
+ if (n > 0)
+ memcpy(res, p, n);
+ } else if (e->format == 'p') {
+ Py_ssize_t n;
+ int isstring;
+ void *p;
+ isstring = PyBytes_Check(v);
+ if (!isstring && !PyByteArray_Check(v)) {
+ PyErr_SetString(StructError,
+ "argument for 'p' must be a bytes object");
+ return -1;
+ }
+ if (isstring) {
+ n = PyBytes_GET_SIZE(v);
+ p = PyBytes_AS_STRING(v);
+ }
+ else {
+ n = PyByteArray_GET_SIZE(v);
+ p = PyByteArray_AS_STRING(v);
+ }
+ if (n > (code->size - 1))
+ n = code->size - 1;
+ if (n > 0)
+ memcpy(res + 1, p, n);
+ if (n > 255)
+ n = 255;
+ *res = Py_SAFE_DOWNCAST(n, Py_ssize_t, unsigned char);
+ } else {
+ if (e->pack(res, v, e) < 0) {
+ if (PyLong_Check(v) && PyErr_ExceptionMatches(PyExc_OverflowError))
+ PyErr_SetString(StructError,
+ "long too large to convert to int");
+ return -1;
+ }
}
+ res += code->size;
}
}
@@ -1907,8 +1919,11 @@
s_sizeof(PyStructObject *self, void *unused)
{
Py_ssize_t size;
+ formatcode *code;
- size = sizeof(PyStructObject) + sizeof(formatcode) * (self->s_len + 1);
+ size = sizeof(PyStructObject) + sizeof(formatcode);
+ for (code = self->s_codes; code->fmtdef != NULL; code++)
+ size += sizeof(formatcode);
return PyLong_FromSsize_t(size);
}