X-Git-Url: https://sigrok.org/gitweb/?a=blobdiff_plain;f=libserialport.h.in;h=85fd098300a9d441b4590622706155a0e60816ea;hb=8645feda604fadd077990dcbf90d687464fa9900;hp=8306fbfec8c16396bfed82c17ead601afbcb41f6;hpb=a33d84f6a0a30feebdb559162d00a936a468a887;p=libserialport.git diff --git a/libserialport.h.in b/libserialport.h.in index 8306fbf..85fd098 100644 --- a/libserialport.h.in +++ b/libserialport.h.in @@ -17,8 +17,55 @@ * along with this program. If not, see . */ -#ifndef LIBSERIALPORT_H -#define LIBSERIALPORT_H +/** + * + * @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_LIBSERIALPORT_H +#define LIBSERIALPORT_LIBSERIALPORT_H #ifdef __cplusplus extern "C" { @@ -40,143 +87,547 @@ extern "C" { #define SP_LIB_VERSION_AGE @SP_LIB_VERSION_AGE@ #define SP_LIB_VERSION_STRING "@SP_LIB_VERSION@" -/* A serial port. */ -struct sp_port { - /* Name used to open the port */ - char *name; - /* OS-specific port handle */ -#ifdef _WIN32 - HANDLE hdl; -#else - int fd; -#endif -}; - -/* Configuration for a serial port. */ -struct sp_port_config { - int baudrate; - int bits; - int parity; - int stopbits; - int rts; - int cts; - int dtr; - int dsr; - int xon_xoff; -}; - -/* Return values. */ -enum { - /* Operation completed successfully. */ +/** Return values. */ +enum sp_return { + /** Operation completed successfully. */ SP_OK = 0, - /* Invalid arguments were passed to the function. */ + /** Invalid arguments were passed to the function. */ SP_ERR_ARG = -1, - /* A system error occured while executing the operation. */ + /** A system error occured while executing the operation. */ SP_ERR_FAIL = -2, - /* A memory allocation failed while executing the operation. */ + /** A memory allocation failed while executing the operation. */ SP_ERR_MEM = -3, }; -/* Port access modes. */ -enum { - /* 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. */ +/** Port access modes. */ +enum sp_mode { + /** Open port for read access. */ + SP_MODE_READ = 1, + /** Open port for write access. */ + SP_MODE_WRITE = 2, + /** Open port in non-blocking mode. */ SP_MODE_NONBLOCK = 4, }; -/* Parity settings. */ -enum { - /* No parity. */ +/** Buffer selection. */ +enum sp_buffer { + /** Input buffer. */ + SP_BUF_INPUT = 1, + /** Output buffer. */ + SP_BUF_OUTPUT = 2, + /** Both buffers. */ + SP_BUF_BOTH = 3, +}; + +/** 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, + /** Odd parity. */ + SP_PARITY_ODD = 1, + /** Even parity. */ + SP_PARITY_EVEN = 2, }; -/* RTS pin behaviour. */ -enum { +/** 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, - SP_RTS_FLOW_CONTROL = 2 + /** RTS used for flow control. */ + SP_RTS_FLOW_CONTROL = 2, }; -/* CTS pin behaviour. */ -enum { +/** 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, - SP_CTS_FLOW_CONTROL = 1 + /** CTS used for flow control. */ + SP_CTS_FLOW_CONTROL = 1, }; -/* DTR pin behaviour. */ -enum { +/** 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, - SP_DTR_FLOW_CONTROL = 2 + /** DTR used for flow control. */ + SP_DTR_FLOW_CONTROL = 2, }; -/* DSR pin behaviour. */ -enum { +/** 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, - SP_DSR_FLOW_CONTROL = 1 + /** DSR used for flow control. */ + SP_DSR_FLOW_CONTROL = 1, }; -/* XON/XOFF flow control behaviour. */ -enum { +/** 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, - SP_XONXOFF_INOUT = 3 + /** XON/XOFF enabled for input and output. */ + SP_XONXOFF_INOUT = 3, }; -/* Standard flow control combinations. */ -enum { +/** 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, - SP_FLOWCONTROL_DTRDSR = 3 + /** Hardware flow control using DTR/DSR signals. */ + SP_FLOWCONTROL_DTRDSR = 3, +}; + +/** Input signals. */ +enum sp_signal { + /** Clear to send. */ + SP_SIG_CTS = 1, + /** Data set ready. */ + SP_SIG_DSR = 2, + /** Data carrier detect. */ + SP_SIG_DCD = 4, + /** Ring indicator. */ + SP_SIG_RI = 8, +}; + +/** 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; }; -/* Enumeration */ -int sp_get_port_by_name(const char *portname, struct sp_port **port_ptr); +/** +@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); -int sp_list_ports(struct sp_port ***list_ptr); -int sp_copy_port(const struct sp_port *port, struct sp_port **copy_ptr); + +/** + * 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); -/* Opening & closing ports */ -int sp_open(struct sp_port *port, int flags); -int sp_close(struct sp_port *port); - -/* Reading, writing and flushing. */ -int sp_read(struct sp_port *port, void *buf, size_t count); -int sp_write(struct sp_port *port, const void *buf, size_t count); -int sp_flush(struct sp_port *port); - -/* Basic port configuration */ -int sp_set_config(struct sp_port *port, struct sp_port_config *config); -int sp_set_baudrate(struct sp_port *port, int baudrate); -int sp_set_bits(struct sp_port *port, int bits); -int sp_set_parity(struct sp_port *port, int parity); -int sp_set_stopbits(struct sp_port *port, int stopbits); -int sp_set_flowcontrol(struct sp_port *port, int flowcontrol); - -/* Advanced port configuration */ -int sp_set_rts(struct sp_port *port, int rts); -int sp_set_cts(struct sp_port *port, int cts); -int sp_set_dtr(struct sp_port *port, int dtr); -int sp_set_dsr(struct sp_port *port, int dsr); -int sp_set_xon_xoff(struct sp_port *port, int xon_xoff); - -/* Error handling */ +/** + * @} + * @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. Data in the selected buffer(s) is discarded. + * + * @param port Pointer to port structure. + * @param buffers Which buffer(s) to flush. + * + * @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, enum sp_buffer buffers); + +/** + * Wait for buffered data to be transmitted. + * + * @param port Pointer to port structure. + * + * @return SP_OK on success, SP_ERR_FAIL on failure, or SP_ERR_ARG + * if an invalid port is passed. + */ +enum sp_return sp_drain(struct sp_port *port); + +/** + * @} + * @defgroup Signal Port signalling operations + * @{ + */ + +/** + * Gets the status of the control signals for the specified port. + * + * The user should allocate a variable of type "enum sp_signal" and pass a + * pointer to this variable to receive the result. The result is a bitmask + * in which individual signals can be checked by bitwise OR with values of + * the sp_signal enum. + * + * @param port Pointer to port structure. + * @param signals Pointer to variable to receive result. + * + * @return SP_OK on success, SP_ERR_FAIL on failure, or SP_ERR_ARG + * if an an invalid port or pointer is passed. + */ +enum sp_return sp_get_signals(struct sp_port *port, enum sp_signal *signals); + +/** + * Put the port transmit line into the break state. + * + * @param port Pointer to port structure. + * + * @return SP_OK on success, SP_ERR_FAIL on failure, or SP_ERR_ARG + * if an invalid port is passed. + */ +enum sp_return sp_start_break(struct sp_port *port); + +/** + * Take the port transmit line out of the break state. + * + * @param port Pointer to port structure. + * + * @return SP_OK on success, SP_ERR_FAIL on failure, or SP_ERR_ARG + * if an invalid port is passed. + */ +enum sp_return sp_end_break(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 */ +#endif