1
0
mirror of git://sigrok.org/libserialport synced 2023-08-10 21:13:24 +03:00
libserialport/libserialport.h.in
2013-11-19 20:10:56 +01:00

557 lines
16 KiB
C

/*
* This file is part of the libserialport project.
*
* Copyright (C) 2013 Martin Ling <martin-libserialport@earth.li>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation, either version 3 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/**
*
* @mainpage libserialport API
*
* Introduction
* ============
*
* libserialport is a minimal library written in C that is intended to take
* care of the OS-specific details when writing software that uses serial ports.
*
* By writing your serial code to use libserialport, you enable it to work
* transparently on any platform supported by the library.
*
* The operations that are supported are:
*
* - @ref Enumeration (obtaining a list of serial ports on the system)
* - @ref Ports
* - @ref Configuration (baud rate, parity, etc.)
* - @ref Data
* - @ref Errors
*
* libserialport is an open source project released under the LGPL3+ license.
*
* API principles
* ==============
*
* The API is simple, and designed to be a minimal wrapper around the serial
* port support in each OS.
*
* Most functions take a pointer to a struct sp_port, which represents a serial
* port. These structures are always allocated and freed by the library, using
* the functions in the @ref Enumeration "Enumeration" section.
*
* All functions can return only three possible error values. @ref SP_ERR_ARG
* indicates the function was called with invalid arguments. @ref SP_ERR_FAIL
* indicates that the OS reported a failure. @ref SP_ERR_MEM indicates that a
* memory allocation failed. All of these error values are negative.
*
* When @ref SP_ERR_FAIL is returned, an error code or string description of
* the error can be obtained by calling sp_last_error_code() or
* sp_last_error_message(). The error code or message is that provided by the
* OS; libserialport does not define any error codes or messages of its own.
*
* Function calls that succeed return @ref SP_OK, which is equal to zero,
* or where otherwise documented a positive value.
*/
#ifndef LIBSERIALPORT_H
#define LIBSERIALPORT_H
#ifdef __cplusplus
extern "C" {
#endif
#include <stddef.h>
#ifdef _WIN32
#include <windows.h>
#endif
/* Package version macros (e.g. for conditional compilation). */
#define SP_PACKAGE_VERSION_MAJOR @SP_PACKAGE_VERSION_MAJOR@
#define SP_PACKAGE_VERSION_MINOR @SP_PACKAGE_VERSION_MINOR@
#define SP_PACKAGE_VERSION_STRING "@SP_PACKAGE_VERSION@"
/* Library/libtool version macros (e.g. for conditional compilation). */
#define SP_LIB_VERSION_CURRENT @SP_LIB_VERSION_CURRENT@
#define SP_LIB_VERSION_REVISION @SP_LIB_VERSION_REVISION@
#define SP_LIB_VERSION_AGE @SP_LIB_VERSION_AGE@
#define SP_LIB_VERSION_STRING "@SP_LIB_VERSION@"
/** Return values. */
enum sp_return {
/** Operation completed successfully. */
SP_OK = 0,
/** Invalid arguments were passed to the function. */
SP_ERR_ARG = -1,
/** A system error occured while executing the operation. */
SP_ERR_FAIL = -2,
/** A memory allocation failed while executing the operation. */
SP_ERR_MEM = -3,
};
/** Port access modes. */
enum sp_mode {
/** Open port for read/write access. */
SP_MODE_RDWR = 1,
/** Open port for read access only. */
SP_MODE_RDONLY = 2,
/** Open port in non-blocking mode. */
SP_MODE_NONBLOCK = 4,
};
/** Parity settings. */
enum sp_parity {
/** Special value to indicate setting should be left alone. */
SP_PARITY_INVALID = -1,
/** No parity. */
SP_PARITY_NONE = 0,
/** Even parity. */
SP_PARITY_EVEN = 1,
/** Odd parity. */
SP_PARITY_ODD = 2,
};
/** RTS pin behaviour. */
enum sp_rts {
/** Special value to indicate setting should be left alone. */
SP_RTS_INVALID = -1,
/** RTS off. */
SP_RTS_OFF = 0,
/** RTS on. */
SP_RTS_ON = 1,
/** RTS used for flow control. */
SP_RTS_FLOW_CONTROL = 2,
};
/** CTS pin behaviour. */
enum sp_cts {
/** Special value to indicate setting should be left alone. */
SP_CTS_INVALID = -1,
/** CTS ignored. */
SP_CTS_IGNORE = 0,
/** CTS used for flow control. */
SP_CTS_FLOW_CONTROL = 1,
};
/** DTR pin behaviour. */
enum sp_dtr {
/** Special value to indicate setting should be left alone. */
SP_DTR_INVALID = -1,
/** DTR off. */
SP_DTR_OFF = 0,
/** DTR on. */
SP_DTR_ON = 1,
/** DTR used for flow control. */
SP_DTR_FLOW_CONTROL = 2,
};
/** DSR pin behaviour. */
enum sp_dsr {
/** Special value to indicate setting should be left alone. */
SP_DSR_INVALID = -1,
/** DSR ignored. */
SP_DSR_IGNORE = 0,
/** DSR used for flow control. */
SP_DSR_FLOW_CONTROL = 1,
};
/** XON/XOFF flow control behaviour. */
enum sp_xonxoff {
/** Special value to indicate setting should be left alone. */
SP_XONXOFF_INVALID = -1,
/** XON/XOFF disabled. */
SP_XONXOFF_DISABLED = 0,
/** XON/XOFF enabled for input only. */
SP_XONXOFF_IN = 1,
/** XON/XOFF enabled for output only. */
SP_XONXOFF_OUT = 2,
/** XON/XOFF enabled for input and output. */
SP_XONXOFF_INOUT = 3,
};
/** Standard flow control combinations. */
enum sp_flowcontrol {
/** No flow control. */
SP_FLOWCONTROL_NONE = 0,
/** Software flow control using XON/XOFF characters. */
SP_FLOWCONTROL_XONXOFF = 1,
/** Hardware flow control using RTS/CTS signals. */
SP_FLOWCONTROL_RTSCTS = 2,
/** Hardware flow control using DTR/DSR signals. */
SP_FLOWCONTROL_DTRDSR = 3,
};
/** A serial port. */
struct sp_port {
/** Name used to open the port. */
char *name;
/** @cond 0 */
/** OS-specific port handle. */
#ifdef _WIN32
HANDLE hdl;
#else
int fd;
#endif
/** @endcond */
};
/** Configuration for a serial port. */
struct sp_port_config {
/** Baud rate in bits per second. */
int baudrate;
/** Number of data bits to use. Valid values are 5 to 8. */
int bits;
/** Parity setting to use. */
enum sp_parity parity;
/** Number of stop bits to use (1 or 2). */
int stopbits;
/** RTS pin mode. */
enum sp_rts rts;
/** CTS pin mode. */
enum sp_cts cts;
/** DTR pin mode. */
enum sp_dtr dtr;
/** DSR pin mode. */
enum sp_dsr dsr;
/** XON/XOFF flow control mode. */
enum sp_xonxoff xon_xoff;
};
/**
@defgroup Enumeration Port enumeration
@{
*/
/**
* Obtain a pointer to a new sp_port structure representing the named port.
*
* The user should allocate a variable of type "struct sp_port *" and pass a
* pointer to this to receive the result.
*
* The result should be freed after use by calling sp_free_port().
*
* @return SP_OK on success, SP_ERR_FAIL on failure, SP_ERR_MEM on allocation
* failure, or SP_ERR_ARG if an invalid pointer is passed. If any error
* is returned, the variable pointed to by port_ptr will be set to NULL.
* Otherwise, it will be set to point to the newly allocated port.
*/
enum sp_return sp_get_port_by_name(const char *portname, struct sp_port **port_ptr);
/**
* Free a port structure obtained from sp_get_port_by_name() or sp_copy_port().
*/
void sp_free_port(struct sp_port *port);
/**
* List the serial ports available on the system.
*
* The result obtained is an array of pointers to sp_port structures,
* terminated by a NULL. The user should allocate a variable of type
* "struct sp_port **" and pass a pointer to this to receive the result.
*
* The result should be freed after use by calling sp_free_port_list().
* If a port from the list is to be used after freeing the list, it must be
* copied first using sp_copy_port().
*
* @return SP_OK on success, SP_ERR_FAIL on failure, SP_ERR_MEM on allocation
* failure, or SP_ERR_ARG if an invalid pointer is passed. If any error
* is returned, the variable pointed to by list_ptr will be set to NULL.
* Otherwise, it will be set to point to the newly allocated array.
*/
enum sp_return sp_list_ports(struct sp_port ***list_ptr);
/**
* Make a new copy of a sp_port structure.
*
* The user should allocate a variable of type "struct sp_port *" and pass a
* pointer to this to receive the result.
*
* The copy should be freed after use by calling sp_free_port().
*
* @return SP_OK on success, SP_ERR_MEM on allocation failure, or SP_ERR_ARG
* if an invalid port or pointer is passed. If any error is returned,
* the variable pointed to by copy_ptr will be set to NULL. Otherwise,
* it will be set to point to the newly allocated copy.
*/
enum sp_return sp_copy_port(const struct sp_port *port, struct sp_port **copy_ptr);
/**
* Free a port list obtained from sp_list_ports().
*
* This will also free all the sp_port structures referred to from the list;
* any that are to be retained must be copied first using sp_copy_port().
*/
void sp_free_port_list(struct sp_port **ports);
/**
* @}
* @defgroup Ports Opening and closing ports
* @{
*/
/**
* Open the specified serial port.
*
* @param port Pointer to port structure.
* @param flags Flags to use when opening the serial port.
*
* @return SP_OK on success, SP_ERR_FAIL on failure, SP_ERR_MEM on allocation
* failure, or SP_ERR_ARG if an invalid port is passed.
*/
enum sp_return sp_open(struct sp_port *port, enum sp_mode flags);
/**
* Close the specified serial port.
*
* @return SP_OK on success, SP_ERR_FAIL on failure, or SP_ERR_ARG
* if an invalid port is passed.
*/
enum sp_return sp_close(struct sp_port *port);
/**
* @}
* @defgroup Configuration Setting port parameters
* @{
*/
/**
* Get the current configuration of the specified serial port.
*
* The user should allocate a struct sp_port_config, then pass a pointer to it
* as the config parameter. The struct will be populated with the port
* configuration.
*
* Any setting that is in a state not recognised or supported by
* libserialport will have its value set to -1 in the struct.
*
* @return SP_OK on success, SP_ERR_FAIL on failure, or SP_ERR_ARG
* for invalid arguments.
*/
enum sp_return sp_get_config(struct sp_port *port, struct sp_port_config *config);
/**
* Set the configuration for the specified serial port.
*
* The user should populate a struct sp_port_config, then pass a pointer to it
* as the config parameter.
*
* To retain the current value of any setting, set that field to -1.
*
* @return SP_OK on success, SP_ERR_FAIL on failure, or SP_ERR_ARG
* for invalid arguments.
*/
enum sp_return sp_set_config(struct sp_port *port, const struct sp_port_config *config);
/**
* Set the baud rate for the specified serial port.
*
* @param port Pointer to port structure.
* @param baudrate Baud rate in bits per second.
*
* @return SP_OK on success, SP_ERR_FAIL on failure, or SP_ERR_ARG
* for invalid arguments.
*/
enum sp_return sp_set_baudrate(struct sp_port *port, int baudrate);
/**
* Set the number of data bits for the specified serial port.
*
* @param port Pointer to port structure.
* @param bits Number of data bits to use. Valid values are 5 to 8.
*
* @return SP_OK on success, SP_ERR_FAIL on failure, or SP_ERR_ARG
* for invalid arguments.
*/
enum sp_return sp_set_bits(struct sp_port *port, int bits);
/**
* Set the parity for the specified serial port.
*
* @param port Pointer to port structure.
* @param parity Parity setting to use.
*
* @return SP_OK on success, SP_ERR_FAIL on failure, or SP_ERR_ARG
* for invalid arguments.
*/
enum sp_return sp_set_parity(struct sp_port *port, enum sp_parity parity);
/**
* Set the number of stop bits for the specified port.
*
* @param port Pointer to port structure.
* @param stopbits Number of stop bits to use (1 or 2).
*
* @return SP_OK on success, SP_ERR_FAIL on failure, or SP_ERR_ARG
* for invalid arguments.
*/
enum sp_return sp_set_stopbits(struct sp_port *port, int stopbits);
/**
* Set the flow control type for the specified serial port.
*
* This function is a wrapper that sets the RTS, CTS, DTR, DSR and
* XON/XOFF settings as necessary for the specified flow control
* type. For more fine-grained control of these settings, use their
* individual configuration functions or the sp_set_config() function.
*
* @param port Pointer to port structure.
* @param flowcontrol Flow control setting to use.
*
* @return SP_OK on success, SP_ERR_FAIL on failure, or SP_ERR_ARG
* for invalid arguments.
*/
enum sp_return sp_set_flowcontrol(struct sp_port *port, enum sp_flowcontrol flowcontrol);
/**
* Set the RTS pin behaviour for the specified port.
*
* @param port Pointer to port structure.
* @param rts RTS pin mode.
*
* @return SP_OK on success, SP_ERR_FAIL on failure, or SP_ERR_ARG
* for invalid arguments.
*/
enum sp_return sp_set_rts(struct sp_port *port, enum sp_rts rts);
/**
* Set the CTS pin behaviour for the specified port.
*
* @param port Pointer to port structure.
* @param cts CTS pin mode.
*
* @return SP_OK on success, SP_ERR_FAIL on failure, or SP_ERR_ARG
* for invalid arguments.
*/
enum sp_return sp_set_cts(struct sp_port *port, enum sp_cts cts);
/**
* Set the DTR pin behaviour for the specified port.
*
* @param port Pointer to port structure.
* @param dtr DTR pin mode.
*
* @return SP_OK on success, SP_ERR_FAIL on failure, or SP_ERR_ARG
* for invalid arguments.
*/
enum sp_return sp_set_dtr(struct sp_port *port, enum sp_dtr dtr);
/**
* Set the RTS pin behaviour for the specified port.
*
* @param port Pointer to port structure.
* @param dsr DSR pin mode.
*
* @return SP_OK on success, SP_ERR_FAIL on failure, or SP_ERR_ARG
* for invalid arguments.
*/
enum sp_return sp_set_dsr(struct sp_port *port, enum sp_dsr dsr);
/**
* Configure XON/XOFF flow control for the specified port.
*
* @param port Pointer to port structure.
* @param xon_xoff XON/XOFF flow control mode.
*
* @return SP_OK on success, SP_ERR_FAIL on failure, or SP_ERR_ARG
* for invalid arguments.
*/
enum sp_return sp_set_xon_xoff(struct sp_port *port, enum sp_xonxoff xon_xoff);
/**
* @}
* @defgroup Data Reading, writing, and flushing data
* @{
*/
/**
* Read bytes from the specified serial port.
*
* Note that this function may return after reading less than the specified
* number of bytes; it is the user's responsibility to iterate as necessary
* in this case.
*
* @param port Pointer to port structure.
* @param buf Buffer in which to store the bytes read.
* @param count Maximum number of bytes to read.
*
* @return The number of bytes read, SP_ERR_FAIL on failure,
* or SP_ERR_ARG for invalid arguments.
*/
enum sp_return sp_read(struct sp_port *port, void *buf, size_t count);
/**
* Write bytes to the specified serial port.
*
* Note that this function may return after writing less than the specified
* number of bytes; it is the user's responsibility to iterate as necessary
* in this case.
*
* @param port Pointer to port structure.
* @param buf Buffer containing the bytes to write.
* @param count Maximum number of bytes to write.
*
* @return The number of bytes written, SP_ERR_FAIL on failure,
* or SP_ERR_ARG for invalid arguments.
*/
enum sp_return sp_write(struct sp_port *port, const void *buf, size_t count);
/**
* Flush serial port buffers.
*
* @return SP_OK on success, SP_ERR_FAIL on failure, or SP_ERR_ARG
* if an invalid port is passed.
*/
enum sp_return sp_flush(struct sp_port *port);
/**
* @}
* @defgroup Errors Obtaining error information
* @{
*/
/**
* Get the error code for a failed operation.
*
* In order to obtain the correct result, this function should be called
* straight after the failure, before executing any other system operations.
*
* @return The system's numeric code for the error that caused the last
* operation to fail.
*/
int sp_last_error_code(void);
/**
* Get the error message for a failed operation.
*
* In order to obtain the correct result, this function should be called
* straight after the failure, before executing other system operations.
*
* @return The system's message for the error that caused the last
* operation to fail. This string may be allocated by the function,
* and should be freed after use by calling sp_free_error_message().
*/
char *sp_last_error_message(void);
/**
* Free an error message returned by sp_last_error_message().
*/
void sp_free_error_message(char *message);
/** @} */
#ifdef __cplusplus
}
#endif
#endif /* LIBSERIALPORT_H */