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buf.c

Purpose

Three buffer families:

  • XByteBuffer_*: dynamic byte buffer
  • XDataBuffer_*: pointer buffer
  • XRingBuffer_*: circular queue of byte buffers

XByteBuffer_* API

uint8_t *XByteData_Dup(const uint8_t *pBuff, size_t nSize)

  • Duplicates nSize bytes and appends a trailing NUL.
  • Returns allocated buffer or NULL.

xbyte_buffer_t *XByteBuffer_New(size_t nSize, int nFastAlloc)

int XByteBuffer_Init(xbyte_buffer_t *pBuffer, size_t nSize, int nFastAlloc)

  • nFastAlloc enables geometric growth on reserve.
  • New allocates the struct and initializes it.
  • Init returns new reserved size or negative status.

void XByteBuffer_Clear(xbyte_buffer_t *pBuffer)

void XByteBuffer_Free(xbyte_buffer_t **pBuffer)

void XByteBuffer_Reset(xbyte_buffer_t *pBuffer)

  • Clear: frees owned storage and resets fields.
  • Free: clears and frees the struct when it was heap-allocated.
  • Reset: keeps allocated storage but sets used length to zero.

int XByteBuffer_Resize(xbyte_buffer_t *pBuffer, size_t nSize)

int XByteBuffer_Reserve(xbyte_buffer_t *pBuffer, size_t nSize)

  • Resize reallocates exact capacity.
  • Reserve ensures space for nUsed + nSize.
  • Return resulting size or negative error.
  • Resize(0) clears buffer and returns XSTDNON.

int XByteBuffer_SetData(xbyte_buffer_t *pBuffer, uint8_t *pData, size_t nSize)

int XByteBuffer_Set(xbyte_buffer_t *pBuffer, xbyte_buffer_t *pSrc)

  • Attach external storage without owning/resizing semantics.
  • Return attached used length.

int XByteBuffer_OwnData(xbyte_buffer_t *pBuffer, uint8_t *pData, size_t nSize)

int XByteBuffer_Own(xbyte_buffer_t *pBuffer, xbyte_buffer_t *pSrc)

  • Transfer ownership into pBuffer.
  • Return resulting owned size.

int XByteBuffer_Add(xbyte_buffer_t *pBuffer, const uint8_t *pData, size_t nSize)

int XByteBuffer_AddByte(xbyte_buffer_t *pBuffer, uint8_t nByte)

int XByteBuffer_AddStr(xbyte_buffer_t *pBuffer, xstring_t *pStr)

int XByteBuffer_AddFmt(xbyte_buffer_t *pBuffer, const char *pFmt, ...)

int XByteBuffer_AddBuff(xbyte_buffer_t *pBuffer, xbyte_buffer_t *pSrc)

  • Append bytes, one byte, xstring_t, formatted text or another byte buffer.
  • Return new used length on success.
  • Return XSTDERR/XSTDNON on failure depending on path.

int XByteBuffer_Insert(xbyte_buffer_t *pBuffer, size_t nPosit, const uint8_t *pData, size_t nSize)

  • Inserts bytes at position or appends when nPosit >= nUsed.
  • Returns new used length or XSTDERR.

int XByteBuffer_Remove(xbyte_buffer_t *pBuffer, size_t nPosit, size_t nSize)

  • Removes bytes in place without shrinking allocation.
  • Returns number of removed bytes or 0.

int XByteBuffer_Delete(xbyte_buffer_t *pBuffer, size_t nPosit, size_t nSize)

  • Removes bytes and then resizes to exact nUsed + 1.
  • Returns buffer status.

int XByteBuffer_Advance(xbyte_buffer_t *pBuffer, size_t nSize)

  • Deletes from the front.
  • Returns new used length.

int XByteBuffer_Terminate(xbyte_buffer_t *pBuffer, size_t nPosit)

int XByteBuffer_NullTerm(xbyte_buffer_t *pBuffer)

  • Terminate truncates used length at nPosit.
  • NullTerm ensures trailing NUL at current end.
  • Return XSTDOK/used length or XSTDERR.

int XByteBuffer_ReadStdin(xbyte_buffer_t *pBuffer)

  • Reads stdin until EOF and appends.
  • Returns final used length or XSTDERR.

uint8_t XByteBuffer_GetByte(xbyte_buffer_t *pBuffer, size_t nIndex)

  • Returns byte at index or 0 when out of range.

xbool_t XByteBuffer_HasData(xbyte_buffer_t *pBuffer)

  • Returns XTRUE when buffer exists and nUsed > 0.

XDataBuffer_* API

int XDataBuffer_Init(xdata_buffer_t *pBuffer, size_t nSize, int nFixed)

  • Allocates pointer table of nSize.
  • Returns capacity or XSTDERR.

void XDataBuffer_Clear(xdata_buffer_t *pBuffer)

void XDataBuffer_Destroy(xdata_buffer_t *pBuffer)

  • Clear runs clearCb for every slot and resets usage.
  • Destroy also frees the pointer table.

int XDataBuffer_Add(xdata_buffer_t *pBuffer, void *pData)

  • Appends pointer.
  • Returns appended index on success.
  • Returns -2 when reallocation failed after full buffer path, or XSTDERR when capacity is already full before growth.

void *XDataBuffer_Set(xdata_buffer_t *pBuffer, unsigned int nIndex, void *pData)

  • Replaces pointer at index.
  • Returns previous pointer.
  • Caveat:
    • current bounds condition is loose and should not be trusted blindly.

void *XDataBuffer_Get(xdata_buffer_t *pBuffer, unsigned int nIndex)

  • Returns pointer at index.
  • Returns NULL when nIndex >= nUsed or nIndex == 0.

void *XDataBuffer_Pop(xdata_buffer_t *pBuffer, unsigned int nIndex)

  • Removes pointer and shifts later items left.
  • Returns removed pointer or NULL.

XRingBuffer_* API

int XRingBuffer_Init(xring_buffer_t *pBuffer, size_t nSize)

  • Allocates nSize internal xbyte_buffer_t slots.
  • Returns capacity or 0.

void XRingBuffer_Reset(xring_buffer_t *pBuffer)

void XRingBuffer_Destroy(xring_buffer_t *pBuffer)

  • Reset clears/free each slot and resets indices.
  • Destroy also frees the slot table.

void XRingBuffer_Update(xring_buffer_t *pBuffer, int nAdd)

void XRingBuffer_Advance(xring_buffer_t *pBuffer)

  • Internal index maintenance helpers.
  • Advance drops the oldest item.

int XRingBuffer_AddData(xring_buffer_t *pBuffer, const uint8_t *pData, size_t nSize)

int XRingBuffer_AddDataAdv(xring_buffer_t *pBuffer, const uint8_t *pData, size_t nSize)

  • AddData appends into current back slot when ring is not full.
  • AddDataAdv auto-advances/drops oldest when full.
  • Return append status from XByteBuffer_Add or 0.

int XRingBuffer_GetData(xring_buffer_t *pBuffer, uint8_t **pData, size_t *pSize)

  • Returns front slot pointer and size.
  • Returns 1 on success, 0 on failure.
  • Caveat:
    • current full-buffer check is inverted; a full ring may be treated as unavailable.

int XRingBuffer_Pop(xring_buffer_t *pBuffer, uint8_t *pData, size_t nSize)

  • Copies front slot bytes into caller buffer, clears that slot and advances.
  • Returns copied byte count.