Common buffer protocol class.
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#include <protocols.h>
Public Types |
enum | type_t { BUF_RD,
BUF_WR,
BUF_RDWR
} |
Public Member Functions |
int | _getch (void) |
| Get a character from the buffer.
|
int | _putch (int ch) |
| Put a character into the buffer.
|
bool | eof (void) |
| Check if at end of input.
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int | err (void) |
bool | flush (void) |
| Flush buffered memory to physical I/O.
|
size_t | get (char *address, size_t count) |
| Get memory from the buffer.
|
size_t | getline (char *string, size_t size) |
| Get text as a line of input from the buffer.
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size_t | getline (string &buffer) |
| Get a string as a line of input from the buffer.
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bool | is_input (void) |
| See if input active.
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bool | is_open (void) |
| See if buffer open.
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bool | is_output (void) |
| See if output active.
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bool | is_pending (void) |
| See if pending input.
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| operator bool () |
| See if buffer open.
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bool | operator! () |
| See if buffer closed.
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size_t | printf (const char *format,...) |
| Print formatted string to the buffer.
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void | purge (void) |
| Purge any pending input or output buffer data.
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size_t | put (const char *address, size_t count=0) |
| Put memory into the buffer.
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size_t | putline (const char *string) |
| Put a string as a line of output to the buffer.
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void | reset (void) |
| Reset input buffer state.
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void | seteof (void) |
| Set eof flag.
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int | get (void) |
| Get the next character.
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int | put (int code) |
| Put the next character.
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Protected Member Functions |
virtual bool | _blocking (void) |
| Return true if blocking.
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virtual void | _clear (void)=0 |
| Method to clear low level i/o error.
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virtual int | _err (void) const =0 |
| Method to get low level i/o error.
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virtual bool | _flush (void) |
| Flush buffer to physical i/o.
|
virtual bool | _pending (void) |
| Check if data is pending.
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virtual size_t | _pull (char *address, size_t size)=0 |
| Method to pull buffer from physical i/o (read).
|
virtual size_t | _push (const char *address, size_t size)=0 |
| Method to push buffer into physical i/o (write).
|
void | allocate (size_t size, type_t access=BUF_RDWR) |
| Allocate I/O buffer(s) of specified size.
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| BufferProtocol () |
| Construct an empty (unallocated) buffer.
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| BufferProtocol (size_t size, type_t access=BUF_RDWR) |
| Construct a buffer of pre-allocated size and access type.
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char * | gather (size_t size) |
| Gather returns a pointer to contiguous input of specified size.
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void | release (void) |
| Release (free) buffer memory.
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char * | request (size_t size) |
| Request workspace in output buffer.
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void | seteol (const char *string) |
| Set end of line marker.
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size_t | unread (void) |
| Get current input position.
|
size_t | unsaved (void) |
| Get current output position.
|
virtual | ~BufferProtocol () |
| Destroy object by releasing buffer memory.
|
Protected Attributes |
const char * | format |
Detailed Description
Common buffer protocol class.
This is used to create objects which will stream character data as needed. This class can support bidirectional streaming as may be needed for serial devices, sockets, and pipes. The buffering mechanisms are hidden from derived classes, and two virtuals are used to communicate with the physical transport.
- Author:
- David Sugar dyfet.nosp@m.@gnu.nosp@m.telep.nosp@m.hony.nosp@m..org
Definition at line 172 of file protocols.h.
Constructor & Destructor Documentation
ucommon::BufferProtocol::BufferProtocol |
( |
size_t |
size, |
|
|
type_t |
access = BUF_RDWR |
|
) |
| |
|
protected |
Construct a buffer of pre-allocated size and access type.
- Parameters:
-
size | of buffer to allocate. |
access | mode of buffer. |
Member Function Documentation
virtual int ucommon::BufferProtocol::_err |
( |
void |
| ) |
const |
|
protectedpure virtual |
Method to get low level i/o error.
- Returns:
- error from low level i/o methods.
int ucommon::BufferProtocol::_getch |
( |
void |
| ) |
|
|
virtual |
Get a character from the buffer.
If no data is available, return EOF.
- Returns:
- character from buffer or eof.
Implements ucommon::CharacterProtocol.
virtual size_t ucommon::BufferProtocol::_pull |
( |
char * |
address, |
|
|
size_t |
size |
|
) |
| |
|
protectedpure virtual |
Method to pull buffer from physical i/o (read).
The address is passed to this virtual since it is hidden as private.
- Parameters:
-
address | of buffer to pull data into. |
size | of buffer area being pulled.. |
- Returns:
- number of read written, 0 on error or end of data.
Implemented in ucommon::SSLBuffer, ucommon::shell::iobuf, ucommon::TCPBuffer, and ucommon::fbuf.
virtual size_t ucommon::BufferProtocol::_push |
( |
const char * |
address, |
|
|
size_t |
size |
|
) |
| |
|
protectedpure virtual |
Method to push buffer into physical i/o (write).
The address is passed to this virtual since it is hidden as private.
- Parameters:
-
address | of data to push. |
size | of data to push. |
- Returns:
- number of bytes written, 0 on error.
int ucommon::BufferProtocol::_putch |
( |
int |
ch | ) |
|
|
virtual |
void ucommon::BufferProtocol::allocate |
( |
size_t |
size, |
|
|
type_t |
access = BUF_RDWR |
|
) |
| |
|
protected |
Allocate I/O buffer(s) of specified size.
If a buffer is currently allocated, it is released.
- Parameters:
-
size | of buffer to allocate. |
access | mode of buffer. |
bool ucommon::BufferProtocol::eof |
( |
void |
| ) |
|
Check if at end of input.
- Returns:
- true if end of data, false if input still buffered.
bool ucommon::BufferProtocol::flush |
( |
void |
| ) |
|
|
inline |
Flush buffered memory to physical I/O.
- Returns:
- true on success, false if not active or fails.
Definition at line 347 of file protocols.h.
char* ucommon::BufferProtocol::gather |
( |
size_t |
size | ) |
|
|
protected |
Gather returns a pointer to contiguous input of specified size.
This may require moving the input data in memory.
- Parameters:
-
- Returns:
- data pointer to gathered data or NULL if not available.
size_t ucommon::BufferProtocol::get |
( |
char * |
address, |
|
|
size_t |
count |
|
) |
| |
Get memory from the buffer.
This method will become "get()" in abi 4 and may become a protected method.
- Parameters:
-
address | of characters save from buffer. |
count | of characters to get from buffer. |
- Returns:
- number of characters actually copied.
size_t ucommon::BufferProtocol::getline |
( |
char * |
string, |
|
|
size_t |
size |
|
) |
| |
Get text as a line of input from the buffer.
The eol character(s) are used to mark the end of a line. Because the end of line character is stripped, the length of the string may be less than the actual count read. If at the end of the file buffer and unable to read more data an error occured then 0 is returned.
- Parameters:
-
string | to save input into. |
size | limit of string to save. |
- Returns:
- count of characters actually read or 0 if at end of data.
size_t ucommon::BufferProtocol::getline |
( |
string & |
buffer | ) |
|
Get a string as a line of input from the buffer.
The eol character(s) are used to mark the end of a line. Because the end of line character is stripped, the length of the string may be less than the actual count read. If at the end of the file buffer and unable to read more data an error occured then 0 is returned.
- Parameters:
-
buffer | to save input into. |
- Returns:
- count of characters actually read or 0 if at end of data.
bool ucommon::BufferProtocol::is_input |
( |
void |
| ) |
|
|
inline |
See if input active.
- Returns:
- true if input active.
Definition at line 422 of file protocols.h.
bool ucommon::BufferProtocol::is_open |
( |
void |
| ) |
|
|
inline |
See if buffer open.
- Returns:
- true if buffer active.
Definition at line 415 of file protocols.h.
bool ucommon::BufferProtocol::is_output |
( |
void |
| ) |
|
|
inline |
See if output active.
- Returns:
- true if output active.
Definition at line 429 of file protocols.h.
bool ucommon::BufferProtocol::is_pending |
( |
void |
| ) |
|
|
inline |
See if pending input.
- Returns:
- true if input pending.
Definition at line 436 of file protocols.h.
ucommon::BufferProtocol::operator bool |
( |
| ) |
|
|
inline |
See if buffer open.
- Returns:
- true if buffer active.
Definition at line 401 of file protocols.h.
bool ucommon::BufferProtocol::operator! |
( |
| ) |
|
|
inline |
See if buffer closed.
- Returns:
- true if buffer inactive.
Definition at line 408 of file protocols.h.
size_t ucommon::BufferProtocol::printf |
( |
const char * |
format, |
|
|
|
... |
|
) |
| |
Print formatted string to the buffer.
The maximum output size is the buffer size, and the operation flushes the buffer.
- Parameters:
-
- Returns:
- number of bytes written.
size_t ucommon::BufferProtocol::put |
( |
const char * |
address, |
|
|
size_t |
count = 0 |
|
) |
| |
Put memory into the buffer.
If count is 0 then put as NULL terminated string. This method will become "put()" in abi 4 and may become a protected method.
- Parameters:
-
address | of characters to put into buffer. |
count | of characters to put into buffer. |
- Returns:
- number of characters actually written.
size_t ucommon::BufferProtocol::putline |
( |
const char * |
string | ) |
|
Put a string as a line of output to the buffer.
The eol character is appended to the end.
- Parameters:
-
- Returns:
- total characters successfully written, including eol chars.
char* ucommon::BufferProtocol::request |
( |
size_t |
size | ) |
|
|
protected |
Request workspace in output buffer.
This returns a pointer to memory from the output buffer and advances the output position. This is sometimes used for a form of zero copy write.
- Parameters:
-
- Returns:
- data pointer or NULL if not available.
void ucommon::BufferProtocol::reset |
( |
void |
| ) |
|
Reset input buffer state.
Drops any pending input.
void ucommon::BufferProtocol::seteol |
( |
const char * |
string | ) |
|
|
inlineprotected |
Set end of line marker.
Normally this is set to cr & lf, which actually supports both lf alone and cr/lf termination of lines. However, putline() will always add the full cr/lf if this mode is used. This option only effects getline() and putline().
- Parameters:
-
string | for eol for getline and putline. |
Definition at line 211 of file protocols.h.
size_t ucommon::BufferProtocol::unread |
( |
void |
| ) |
|
|
inlineprotected |
Get current input position.
Sometimes used to help compute and report a "tell" offset.
- Returns:
- offset of input buffer.
Definition at line 293 of file protocols.h.
size_t ucommon::BufferProtocol::unsaved |
( |
void |
| ) |
|
|
inlineprotected |
Get current output position.
Sometimes used to help compute a "trunc" operation.
Definition at line 300 of file protocols.h.
The documentation for this class was generated from the following file: