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unix/main: When preparing sys.path, allocate exact strings on uPy heap.

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Due to the way modern compilers work (allocating space for stack vars once
at tha start of function, and deallocating once on exit from), using
intermediate stack buffer of big size caused blockage of 4K (PATH_MAX)
on stack for the entire duration of MicroPython execution.
This commit is contained in:
Paul Sokolovsky 2016-07-09 01:48:07 +03:00
parent 649b69a1db
commit 520f35632d
1 changed files with 6 additions and 4 deletions
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10
unix/main.c
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@ -444,10 +444,12 @@ MP_NOINLINE int main_(int argc, char **argv) {
}
if (p[0] == '~' && p[1] == '/' && home != NULL) {
// Expand standalone ~ to $HOME
CHECKBUF(buf, PATH_MAX);
CHECKBUF_APPEND(buf, home, strlen(home));
CHECKBUF_APPEND(buf, p + 1, (size_t)(p1 - p - 1));
path_items[i] = MP_OBJ_NEW_QSTR(qstr_from_strn(buf, CHECKBUF_LEN(buf)));
int home_l = strlen(home);
vstr_t vstr;
vstr_init(&vstr, home_l + (p1 - p - 1) + 1);
vstr_add_strn(&vstr, home, home_l);
vstr_add_strn(&vstr, p + 1, p1 - p - 1);
path_items[i] = mp_obj_new_str_from_vstr(&mp_type_str, &vstr);
} else {
path_items[i] = MP_OBJ_NEW_QSTR(qstr_from_strn(p, p1 - p));
}