/***
This file is part of systemd.
Copyright 2013 Lennart Poettering
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include "bus-gvariant.h"
#include "bus-signature.h"
#include "bus-type.h"
int bus_gvariant_get_size(const char *signature) {
const char *p;
int sum = 0, r;
/* For fixed size structs. Fails for variable size structs. */
p = signature;
while (*p != 0) {
size_t n;
r = signature_element_length(p, &n);
if (r < 0)
return r;
else {
char t[n+1];
memcpy(t, p, n);
t[n] = 0;
r = bus_gvariant_get_alignment(t);
if (r < 0)
return r;
sum = ALIGN_TO(sum, r);
}
switch (*p) {
case SD_BUS_TYPE_BOOLEAN:
case SD_BUS_TYPE_BYTE:
sum += 1;
break;
case SD_BUS_TYPE_INT16:
case SD_BUS_TYPE_UINT16:
sum += 2;
break;
case SD_BUS_TYPE_INT32:
case SD_BUS_TYPE_UINT32:
case SD_BUS_TYPE_UNIX_FD:
sum += 4;
break;
case SD_BUS_TYPE_INT64:
case SD_BUS_TYPE_UINT64:
case SD_BUS_TYPE_DOUBLE:
sum += 8;
break;
case SD_BUS_TYPE_STRUCT_BEGIN:
case SD_BUS_TYPE_DICT_ENTRY_BEGIN: {
if (n == 2) {
/* unary type () has fixed size of 1 */
r = 1;
} else {
char t[n-1];
memcpy(t, p + 1, n - 2);
t[n - 2] = 0;
r = bus_gvariant_get_size(t);
if (r < 0)
return r;
}
sum += r;
break;
}
case SD_BUS_TYPE_STRING:
case SD_BUS_TYPE_OBJECT_PATH:
case SD_BUS_TYPE_SIGNATURE:
case SD_BUS_TYPE_ARRAY:
case SD_BUS_TYPE_VARIANT:
return -EINVAL;
default:
assert_not_reached("Unknown signature type");
}
p += n;
}
r = bus_gvariant_get_alignment(signature);
if (r < 0)
return r;
return ALIGN_TO(sum, r);
}
int bus_gvariant_get_alignment(const char *signature) {
size_t alignment = 1;
const char *p;
int r;
p = signature;
while (*p != 0 && alignment < 8) {
size_t n;
int a;
r = signature_element_length(p, &n);
if (r < 0)
return r;
switch (*p) {
case SD_BUS_TYPE_BYTE:
case SD_BUS_TYPE_BOOLEAN:
case SD_BUS_TYPE_STRING:
case SD_BUS_TYPE_OBJECT_PATH:
case SD_BUS_TYPE_SIGNATURE:
a = 1;
break;
case SD_BUS_TYPE_INT16:
case SD_BUS_TYPE_UINT16:
a = 2;
break;
case SD_BUS_TYPE_INT32:
case SD_BUS_TYPE_UINT32:
case SD_BUS_TYPE_UNIX_FD:
a = 4;
break;
case SD_BUS_TYPE_INT64:
case SD_BUS_TYPE_UINT64:
case SD_BUS_TYPE_DOUBLE:
case SD_BUS_TYPE_VARIANT:
a = 8;
break;
case SD_BUS_TYPE_ARRAY: {
char t[n];
memcpy(t, p + 1, n - 1);
t[n - 1] = 0;
a = bus_gvariant_get_alignment(t);
break;
}
case SD_BUS_TYPE_STRUCT_BEGIN:
case SD_BUS_TYPE_DICT_ENTRY_BEGIN: {
char t[n-1];
memcpy(t, p + 1, n - 2);
t[n - 2] = 0;
a = bus_gvariant_get_alignment(t);
break;
}
default:
assert_not_reached("Unknown signature type");
}
if (a < 0)
return a;
assert(a > 0 && a <= 8);
if ((size_t) a > alignment)
alignment = (size_t) a;
p += n;
}
return alignment;
}
int bus_gvariant_is_fixed_size(const char *signature) {
const char *p;
int r;
assert(signature);
p = signature;
while (*p != 0) {
size_t n;
r = signature_element_length(p, &n);
if (r < 0)
return r;
switch (*p) {
case SD_BUS_TYPE_STRING:
case SD_BUS_TYPE_OBJECT_PATH:
case SD_BUS_TYPE_SIGNATURE:
case SD_BUS_TYPE_ARRAY:
case SD_BUS_TYPE_VARIANT:
return 0;
case SD_BUS_TYPE_BYTE:
case SD_BUS_TYPE_BOOLEAN:
case SD_BUS_TYPE_INT16:
case SD_BUS_TYPE_UINT16:
case SD_BUS_TYPE_INT32:
case SD_BUS_TYPE_UINT32:
case SD_BUS_TYPE_UNIX_FD:
case SD_BUS_TYPE_INT64:
case SD_BUS_TYPE_UINT64:
case SD_BUS_TYPE_DOUBLE:
break;
case SD_BUS_TYPE_STRUCT_BEGIN:
case SD_BUS_TYPE_DICT_ENTRY_BEGIN: {
char t[n-1];
memcpy(t, p + 1, n - 2);
t[n - 2] = 0;
r = bus_gvariant_is_fixed_size(t);
if (r <= 0)
return r;
break;
}
default:
assert_not_reached("Unknown signature type");
}
p += n;
}
return true;
}
size_t bus_gvariant_determine_word_size(size_t sz, size_t extra) {
if (sz + extra <= 0xFF)
return 1;
else if (sz + extra*2 <= 0xFFFF)
return 2;
else if (sz + extra*4 <= 0xFFFFFFFF)
return 4;
else
return 8;
}
size_t bus_gvariant_read_word_le(void *p, size_t sz) {
union {
uint16_t u16;
uint32_t u32;
uint64_t u64;
} x;
assert(p);
if (sz == 1)
return *(uint8_t*) p;
memcpy(&x, p, sz);
if (sz == 2)
return le16toh(x.u16);
else if (sz == 4)
return le32toh(x.u32);
else if (sz == 8)
return le64toh(x.u64);
assert_not_reached("unknown word width");
}
void bus_gvariant_write_word_le(void *p, size_t sz, size_t value) {
union {
uint16_t u16;
uint32_t u32;
uint64_t u64;
} x;
assert(p);
assert(sz == 8 || (value < (1ULL << (sz*8))));
if (sz == 1) {
*(uint8_t*) p = value;
return;
} else if (sz == 2)
x.u16 = htole16((uint16_t) value);
else if (sz == 4)
x.u32 = htole32((uint32_t) value);
else if (sz == 8)
x.u64 = htole64((uint64_t) value);
else
assert_not_reached("unknown word width");
memcpy(p, &x, sz);
}