77 lines
1.4 KiB
C
77 lines
1.4 KiB
C
#include "varint.h"
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size_t varint_uint32_pack(uint32_t value, uint8_t* output) {
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uint8_t* start = output;
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while(value >= 0x80) {
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*output++ = (value | 0x80);
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value >>= 7;
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}
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*output++ = value;
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return output - start;
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}
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size_t varint_uint32_unpack(uint32_t* value, const uint8_t* input, size_t input_size) {
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size_t i;
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uint32_t parsed = 0;
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for(i = 0; i < input_size; i++) {
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parsed |= (input[i] & 0x7FUL) << (7 * i);
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if(!(input[i] & 0x80)) {
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break;
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}
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}
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*value = parsed;
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return i + 1;
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}
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size_t varint_uint32_length(uint32_t value) {
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size_t size = 0;
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while(value >= 0x80) {
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value >>= 7;
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size++;
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}
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size++;
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return size;
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}
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size_t varint_int32_pack(int32_t value, uint8_t* output) {
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uint32_t v;
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if(value >= 0) {
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v = value * 2;
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} else {
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v = (value * -2) - 1;
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}
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return varint_uint32_pack(v, output);
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}
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size_t varint_int32_unpack(int32_t* value, const uint8_t* input, size_t input_size) {
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uint32_t v;
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size_t size = varint_uint32_unpack(&v, input, input_size);
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if(v & 1) {
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*value = (int32_t)(v + 1) / (-2);
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} else {
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*value = v / 2;
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}
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return size;
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}
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size_t varint_int32_length(int32_t value) {
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uint32_t v;
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if(value >= 0) {
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v = value * 2;
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} else {
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v = (value * -2) - 1;
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}
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return varint_uint32_length(v);
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}
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