diff options
Diffstat (limited to 'src/libsystemd/sd-bus/bus-gvariant.c')
| -rw-r--r-- | src/libsystemd/sd-bus/bus-gvariant.c | 299 |
1 files changed, 299 insertions, 0 deletions
diff --git a/src/libsystemd/sd-bus/bus-gvariant.c b/src/libsystemd/sd-bus/bus-gvariant.c new file mode 100644 index 0000000..ba503b3 --- /dev/null +++ b/src/libsystemd/sd-bus/bus-gvariant.c @@ -0,0 +1,299 @@ +/* SPDX-License-Identifier: LGPL-2.1+ */ + +#include <errno.h> +#include <string.h> + +#include "sd-bus.h" + +#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); +} |