XBinder  Version 2.9.x
Classes | Typedefs | Functions
Context Message Buffer Read/Write Functions

The context message buffer can be written to, or read from, using various functions. More...

Classes

struct  _OSRTBufLocDescr
 Buffer location descriptor. More...
 

Typedefs

typedef struct _OSRTBufLocDescr OSRTBufLocDescr
 Buffer location descriptor.
 

Functions

EXTERNRT int rtxCheckOutputBuffer (OSCTXT *pctxt, size_t nbytes)
 This function checks to ensure that the output buffer has sufficient space to hold an additional nbytes full bytes (if there is a partially filled byte, it is treated as though full). More...
 
EXTERNRT OSBOOL rtxIsOutputBufferFlushable (OSCTXT *pctxt)
 This function returns true if the context buffer can be flushed to a stream by calling rtxFlushOutputBuffer. More...
 
EXTERNRT int rtxFlushOutputBuffer (OSCTXT *pctxt)
 This function flushes the buffer to a stream. More...
 
EXTERNRT int rtxExpandOutputBuffer (OSCTXT *pctxt, size_t nbytes)
 This function attempts to ensure the output buffer has at least the given number of bytes available. More...
 
EXTERNRT int rtxCheckInputBuffer (OSCTXT *pctxt, size_t nbytes)
 Ensures the given number of bytes are available in the context buffer. More...
 
EXTERNRT int rtxLoadInputBuffer (OSCTXT *pctxt, OSSIZE nbytes)
 This is for meant for internal use by the runtime. More...
 
EXTERNRT int rtxPeekByte (OSCTXT *pctxt, OSOCTET *pbyte)
 This function peeks at the next byte of input, if there is one before EOF. More...
 
EXTERNRT int rtxPeekBytes (OSCTXT *pctxt, OSOCTET *pdata, OSSIZE bufsize, OSSIZE nocts, OSSIZE *pactual)
 This function peeks at the next nocts bytes of input, peeking at fewer bytes if EOF is encountered first. More...
 
EXTERNRT int rtxReadBytesSafe (OSCTXT *pctxt, OSOCTET *buffer, size_t bufsize, size_t nocts)
 This function safely reads bytes from the currently open stream or memory buffer into the given static buffer. More...
 
EXTERNRT int rtxReadBytes (OSCTXT *pctxt, OSOCTET *pdata, size_t nocts)
 This function reads bytes from the currently open stream or memory buffer. More...
 
EXTERNRT int rtxReadBytesDynamic (OSCTXT *pctxt, OSOCTET **ppdata, size_t nocts, OSBOOL *pMemAlloc)
 This function reads bytes from the currently open stream or memory buffer. More...
 
EXTERNRT int rtxWriteBytes (OSCTXT *pctxt, const OSOCTET *pdata, size_t nocts)
 This function writes bytes to the currently open stream or memory buffer. More...
 
EXTERNRT int rtxWriteIndent (OSCTXT *pctxt)
 This function writes a newline followed by indentation whitespace to the buffer. More...
 
EXTERNRT void rtxIndentDecr (OSCTXT *pctxt)
 This decreases the indentation level set in the given context by updating the indent member. More...
 
EXTERNRT void rtxIndentIncr (OSCTXT *pctxt)
 This increases the indentation level set in the given context by updating the indent member. More...
 
EXTERNRT void rtxIndentReset (OSCTXT *pctxt)
 This resets the indentation level in the given context to zero. More...
 
EXTERNRT size_t rtxGetIndentLevels (OSCTXT *pctxt)
 This returns the number of levels of indentation set in the given context. More...
 
EXTERNRT OSBOOL rtxCanonicalSort (OSOCTET *refPoint, OSRTSList *pList, OSBOOL normal)
 Sort a list of buffer locations, referring to component encodings, by comparing the referenced encodings as octet strings. More...
 
EXTERNRT int rtxEncCanonicalSort (OSCTXT *pctxt, OSCTXT *pMemCtxt, OSRTSList *pList)
 Encode the encodings held in pMemCtxt into pctxt, first sorting them as required for canonical BER (and other encoding rules) by X.690 11.6. More...
 
EXTERNRT void rtxGetBufLocDescr (OSCTXT *pctxt, OSRTBufLocDescr *pDescr)
 Set the buffer location description's offset (pDescr->offset) to the current position in pCtxt's buffer.
 
EXTERNRT void rtxAddBufLocDescr (OSCTXT *pctxt, OSRTSList *pElemList, OSRTBufLocDescr *pDescr)
 Create a new Asn1BufLocDescr for an element just encoded and append it to pElemList. More...
 

Detailed Description

The context message buffer can be written to, or read from, using various functions.

Function Documentation

◆ rtxAddBufLocDescr()

EXTERNRT void rtxAddBufLocDescr ( OSCTXT pctxt,
OSRTSList *  pElemList,
OSRTBufLocDescr pDescr 
)

Create a new Asn1BufLocDescr for an element just encoded and append it to pElemList.

Parameters
pctxtPointer to context where data has been encoded.
pElemListList of Asn1BufLocDescr to which a new entry will be added.
pDescrPointer to Asn1BufLocDescr whose offset indicates the start of the element just encoded. The new Asn1BufLocDescr that is added will have the same offset and will have numocts determined by this offset and pctxt's current buffer position.

◆ rtxCanonicalSort()

EXTERNRT OSBOOL rtxCanonicalSort ( OSOCTET *  refPoint,
OSRTSList *  pList,
OSBOOL  normal 
)

Sort a list of buffer locations, referring to component encodings, by comparing the referenced encodings as octet strings.

The sorting can be used with canonical-BER (CER), distinguished-BER (DER), and canonical-XER (XER).

Encoding into the buffer may be done as a normal encoding (start to end) or as a reverse encoding (end to start). This affects the parameters as described below.

Parameters
refPointReference point in the buffer for the buffer locations. For normal encoding, refPoint is the start of the buffer; for reverse encoding, refPoint is the end of the buffer.
pListList of OSRTBufLocDescr, each of which locates the start of an encoded component. The offsets for the locations are relative to refPoint. If normal is TRUE, this function orders the list from least to greatest. Otherwise, it is ordered from greatest to least.
normalTRUE for normal encoding; FALSE for reverse encoding. This tells the function whether to add or substract offsets from refPoint to locate the component encodings and also how to order the list.
Returns
TRUE if any changes to pList were made; FALSE otherwise (meaning the list was already in the desired order).

◆ rtxCheckInputBuffer()

EXTERNRT int rtxCheckInputBuffer ( OSCTXT pctxt,
size_t  nbytes 
)

Ensures the given number of bytes are available in the context buffer.

If a stream is attached to the context and is being buffered by the context buffer, this may read from the stream to fill the buffer. Thus this function may alter the context buffer byteIndex and size. Any bytes read from the stream will be sent to the capture buffer, if there is one.

Returns
0 on success, or less than zero on failure. RTERR_ENDOFBUF or RTERR_ENDOFFILE (depending on whether the source is a stream or not) is returned if the requested number of bytes are not available in the input.

◆ rtxCheckOutputBuffer()

EXTERNRT int rtxCheckOutputBuffer ( OSCTXT pctxt,
size_t  nbytes 
)

This function checks to ensure that the output buffer has sufficient space to hold an additional nbytes full bytes (if there is a partially filled byte, it is treated as though full).

Dynamic buffers are resized if the check fails, while static buffers induce a buffer overflow error. This function may return RTERR_NOMEM if reallocating the dynamic buffer fails.

Parameters
pctxtPointer to a context structure.
nbytesThe requested capacity for the buffer.
Returns
0 on success, or less than zero on failure.

◆ rtxEncCanonicalSort()

EXTERNRT int rtxEncCanonicalSort ( OSCTXT pctxt,
OSCTXT pMemCtxt,
OSRTSList *  pList 
)

Encode the encodings held in pMemCtxt into pctxt, first sorting them as required for canonical BER (and other encoding rules) by X.690 11.6.

Parameters
pctxtPointer to context structure into which the sorted encodings should be encoded.
pMemCtxtPointer to context structure which holds the unsorted encodings.
pListList of Asn1BufLocDescr, each of which locates an encoding in pMemCtxt's buffer, the whole being the encodings that are to be sorted.

◆ rtxExpandOutputBuffer()

EXTERNRT int rtxExpandOutputBuffer ( OSCTXT pctxt,
size_t  nbytes 
)

This function attempts to ensure the output buffer has at least the given number of bytes available.

A partially full byte in the buffer counts as being available. Dynamic buffers are resized, if necessary, while static buffers induce a buffer overflow error. This function may return RTERR_NOMEM if reallocating a dynamic buffer fails.

Parameters
pctxtPointer to a context structure.
nbytesThe requested capacity for the buffer.
Returns
0 on success, or less than zero on failure.

◆ rtxFlushOutputBuffer()

EXTERNRT int rtxFlushOutputBuffer ( OSCTXT pctxt)

This function flushes the buffer to a stream.

This function MUST only be called if rtxIsOutputBufferFlushable(pctxt) returns TRUE; the behavior is otherwise undefined. After a successful call, pctxt->buffer.byteIndex == 0. Note that pctxt->buffer.bitOffset is not changed - if there was a partial byte in the buffer before this call, there will be a partial by afterward.

Parameters
pctxtPointer to a context structure.
Returns
0 on success, or less than zero on failure.

◆ rtxGetIndentLevels()

EXTERNRT size_t rtxGetIndentLevels ( OSCTXT pctxt)

This returns the number of levels of indentation set in the given context.

Currently, the indentation level in the context affects rtxPrintToStreamIndent (when used with a non-null OSCTXT), rtxWriteIndent, and rtJsonEncIndent, meaning it currently affects print-to-stream output, Abstract Syntax Notation output, and JSON (JER) output.

Parameters
pctxtPointer to context block structure.

◆ rtxIndentDecr()

EXTERNRT void rtxIndentDecr ( OSCTXT pctxt)

This decreases the indentation level set in the given context by updating the indent member.

See also
rtxGetIndentLevels
Parameters
pctxtPointer to context block structure.

◆ rtxIndentIncr()

EXTERNRT void rtxIndentIncr ( OSCTXT pctxt)

This increases the indentation level set in the given context by updating the indent member.

See also
rtxGetIndentLevels
Parameters
pctxtPointer to context block structure.

◆ rtxIndentReset()

EXTERNRT void rtxIndentReset ( OSCTXT pctxt)

This resets the indentation level in the given context to zero.

See also
rtxGetIndentLevels
Parameters
pctxtPointer to context block structure.

◆ rtxIsOutputBufferFlushable()

EXTERNRT OSBOOL rtxIsOutputBufferFlushable ( OSCTXT pctxt)

This function returns true if the context buffer can be flushed to a stream by calling rtxFlushOutputBuffer.

This function is used to determine whether it is safe to call rtxFlushOutputBuffer.

Parameters
pctxtPointer to a context structure.
Returns
TRUE if the buffer can be flushed; FALSE is not.

◆ rtxLoadInputBuffer()

EXTERNRT int rtxLoadInputBuffer ( OSCTXT pctxt,
OSSIZE  nbytes 
)

This is for meant for internal use by the runtime.

Read at least as many bytes from the context's input stream into the context buffer as necessary to make nbytes of data available in the context buffer.

Upon return, pctxt.buffer.byteIndex + nbytes <= pctxt.buffer.size OR EOF has been reached OR an error has been logged and is being returned.

If the context buffer has not been created, this will create it. If the context buffer needs to be made larger, this will enlarge it or else log, and return, an error.

Parameters
pctxtA context with an attached stream using the context's buffer as a buffer for the stream.
Returns
0 or or negative error. EOF is not considered an error.

◆ rtxPeekByte()

EXTERNRT int rtxPeekByte ( OSCTXT pctxt,
OSOCTET *  pbyte 
)

This function peeks at the next byte of input, if there is one before EOF.

A return of 1 ensures the peeked byte can be skipped by incrementing pctxt->buffer.byteIndex.

Parameters
pbyteReceives the value of the peeked byte.
Returns
0 if there was no byte to peek at. 1 if there was a byte to peek at. <0 if there was an error.

◆ rtxPeekBytes()

EXTERNRT int rtxPeekBytes ( OSCTXT pctxt,
OSOCTET *  pdata,
OSSIZE  bufsize,
OSSIZE  nocts,
OSSIZE *  pactual 
)

This function peeks at the next nocts bytes of input, peeking at fewer bytes if EOF is encountered first.

A returned value (in *pactual) of n (>=0) ensures that n (or fewer) peeked bytes can be skipped by adding n (or less) to pctxt->buffer.byteIndex.

Parameters
pdataReceives the value of the peeked bytes.
bufsizeSize of pdata. If less than nocts, nocts will be adjusted accordingly.
noctsThe number of bytes to peek.
pactualReceives the actual number of bytes peeked.
Returns
0 for success <0 if there was an error.

◆ rtxReadBytes()

EXTERNRT int rtxReadBytes ( OSCTXT pctxt,
OSOCTET *  pdata,
size_t  nocts 
)

This function reads bytes from the currently open stream or memory buffer.

Parameters
pctxtPointer to a context structure.
pdataPointer to byte array where bytes are to be copied.
noctsNumber of bytes (octets) to read.
Returns
Status of the operation: 0 if success, negative value if error.

◆ rtxReadBytesDynamic()

EXTERNRT int rtxReadBytesDynamic ( OSCTXT pctxt,
OSOCTET **  ppdata,
size_t  nocts,
OSBOOL *  pMemAlloc 
)

This function reads bytes from the currently open stream or memory buffer.

In this case the function MAY allocate memory to hold the read bytes. It will only do this if the requested number of bytes will not fit in the context buffer; othwerwise, a pointer to a location in the context buffer is returned. If memory was allocated, it should be freed using rtxMemFreePtr.

Parameters
pctxtPointer to a context structure.
ppdataPointer to byte buffer pointer.
noctsNumber of bytes (octets) to read.
pMemAllocPointer to boolean value which is set to true if memory was allocated to hold requested bytes.
Returns
Status of the operation: 0 if success, negative value if error.

◆ rtxReadBytesSafe()

EXTERNRT int rtxReadBytesSafe ( OSCTXT pctxt,
OSOCTET *  buffer,
size_t  bufsize,
size_t  nocts 
)

This function safely reads bytes from the currently open stream or memory buffer into the given static buffer.

This function is preferred over rtxReadBytes because it will detect buffer overflow.

Parameters
pctxtPointer to a context structure.
bufferStatic buffer into which bytes are to be read.
bufsizeSize of the static buffer.
noctsNumber of bytes (octets) to read.
Returns
Status of the operation: 0 if success, negative value if error.

◆ rtxWriteBytes()

EXTERNRT int rtxWriteBytes ( OSCTXT pctxt,
const OSOCTET *  pdata,
size_t  nocts 
)

This function writes bytes to the currently open stream or memory buffer.

Parameters
pctxtPointer to a context structure.
pdataPointer to location where bytes are to be copied.
noctsNumber of bytes to read.
Returns
I/O byte count.

◆ rtxWriteIndent()

EXTERNRT int rtxWriteIndent ( OSCTXT pctxt)

This function writes a newline followed by indentation whitespace to the buffer.

The amount of indentation to add is determined by the indent member variable in the context structure.

If context flag OSNOWHITESPACE is set, this function will do nothing.

Parameters
pctxtPointer to context block structure.
Returns
Completion status of operation:
  • 0 = success,
  • negative return value is error.