int64_t Value = 0;
unsigned Shift = 0;
uint8_t Byte;
+ if (error)
+ *error = nullptr;
do {
if (end && p == end) {
if (error)
Value |= (int64_t(Byte & 0x7f) << Shift);
Shift += 7;
} while (Byte >= 128);
- // Sign extend negative numbers.
- if (Byte & 0x40)
+ // Sign extend negative numbers if needed.
+ if (Shift < 64 && (Byte & 0x40))
Value |= (-1ULL) << Shift;
if (n)
*n = (unsigned)(p - orig_p);
}
int64_t DataExtractor::getSLEB128(uint32_t *offset_ptr) const {
- int64_t result = 0;
- if (Data.empty())
- return 0;
+ assert(*offset_ptr <= Data.size());
- unsigned shift = 0;
- uint32_t offset = *offset_ptr;
- uint8_t byte = 0;
-
- while (isValidOffset(offset)) {
- byte = Data[offset++];
- result |= uint64_t(byte & 0x7f) << shift;
- shift += 7;
- if ((byte & 0x80) == 0) {
- // Sign bit of byte is 2nd high order bit (0x40)
- if (shift < 64 && (byte & 0x40))
- result |= -(1ULL << shift);
-
- *offset_ptr = offset;
- return result;
- }
- }
- return 0;
+ const char *error;
+ unsigned bytes_read;
+ int64_t result = decodeSLEB128(
+ reinterpret_cast<const uint8_t *>(Data.data() + *offset_ptr), &bytes_read,
+ reinterpret_cast<const uint8_t *>(Data.data() + Data.size()), &error);
+ if (error)
+ return 0;
+ *offset_ptr += bytes_read;
+ return result;
}