82 lines
1.6 KiB
C
82 lines
1.6 KiB
C
#include "axl_rle.h"
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#include "axl_vlq.h"
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#include "axl_memory.h"
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u32 axl_rle_encode(const u8* src, u32 src_size, u8* dst, u32 dst_size)
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{
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if (src == NULL || dst == NULL || src_size == 0 || dst_size == 0)
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{
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return 0;
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}
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u8 vlq_buff[AXL_VLQ_MAX_LEN];
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const u8* head = src;
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u32 used_size = 0;
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while(head < src + src_size)
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{
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const u8 value = *head;
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u32 count = 0;
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while(head < src + src_size && *head == value)
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{
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count++;
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head++;
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}
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u32 vlq_len = axl_vlq_encode(count, vlq_buff);
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u32 req_size = vlq_len + 1;
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if(req_size + used_size > dst_size)
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{
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return 0;
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}
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axl_memcpy(dst, vlq_buff, vlq_len);
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dst += vlq_len;
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axl_memcpy(dst, &value, 1);
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dst += 1;
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used_size += req_size;
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}
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return used_size;
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}
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u32 axl_rle_decode(const u8* src, u32 src_size, u8* dst, u32 dst_size)
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{
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if (src == NULL || dst == NULL || src_size == 0 || dst_size == 0)
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{
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return 0;
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}
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const u8* head = src;
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u32 used_size = 0;
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while(head < src + src_size)
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{
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u32 repeat_count;
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u32 vlq_len = axl_vlq_decode(head, &repeat_count);
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if(vlq_len == 0 || head + vlq_len + 1 > src + src_size)
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{
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return 0;
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}
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head += vlq_len;
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const u8 value = *head;
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head++;
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used_size += repeat_count;
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if(used_size > dst_size)
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{
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return 0;
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}
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axl_memset(dst, value, repeat_count);
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dst += repeat_count;
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}
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return used_size;
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}
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