X-Git-Url: http://sigrok.org/gitweb/?a=blobdiff_plain;f=libserialport.h.in;h=6aa5f6f1201e212c8fd8aae5ad8bd1445a88b77b;hb=59131d602894f5e2f8776fa9f4736d360f67579f;hp=7c50c7e3a0b0ee668dab303a81ecf2c669e281cf;hpb=6aabf62a90915a94c8415ba4e29da96c05b0526b;p=libserialport.git diff --git a/libserialport.h.in b/libserialport.h.in index 7c50c7e..6aa5f6f 100644 --- a/libserialport.h.in +++ b/libserialport.h.in @@ -34,6 +34,7 @@ * - @ref Enumeration (obtaining a list of serial ports on the system) * - @ref Ports * - @ref Configuration (baud rate, parity, etc.) + * - @ref Signals (modem control lines, breaks, etc.) * - @ref Data * - @ref Errors * @@ -49,7 +50,8 @@ * 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 four possible error values: + * Most functions have return type @ref sp_return and can return only four + * possible error values: * * - @ref SP_ERR_ARG means that a function was called with invalid * arguments. This implies a bug in the caller. The arguments passed would @@ -69,8 +71,9 @@ * * All of these error values are negative. * - * Function calls that succeed return @ref SP_OK, which is equal to zero, - * or where otherwise documented a positive value. + * Calls that succeed return @ref SP_OK, which is equal to zero. Some functions + * declared @ref sp_return can also return a positive value for a successful + * numeric result, e.g. sp_read() and sp_write(). */ #ifndef LIBSERIALPORT_LIBSERIALPORT_H @@ -226,40 +229,10 @@ enum sp_signal { }; /** 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 */ -}; +struct sp_port; /** 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; -}; +struct sp_port_config; /** @defgroup Enumeration Port enumeration @@ -274,10 +247,10 @@ struct sp_port_config { * * 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. + * 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. + * + * @return SP_OK upon success, a negative error code otherwise. */ enum sp_return sp_get_port_by_name(const char *portname, struct sp_port **port_ptr); @@ -297,10 +270,10 @@ void sp_free_port(struct sp_port *port); * 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. + * 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. + * + * @return SP_OK upon success, a negative error code otherwise. */ enum sp_return sp_list_ports(struct sp_port ***list_ptr); @@ -312,10 +285,10 @@ enum sp_return sp_list_ports(struct sp_port ***list_ptr); * * 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. + * 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. + * + * @return SP_OK upon success, a negative error code otherwise. */ enum sp_return sp_copy_port(const struct sp_port *port, struct sp_port **copy_ptr); @@ -329,7 +302,7 @@ void sp_free_port_list(struct sp_port **ports); /** * @} - * @defgroup Ports Opening and closing ports + * @defgroup Ports Opening, closing and querying ports * @{ */ @@ -339,50 +312,111 @@ void sp_free_port_list(struct sp_port **ports); * @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. + * @return SP_OK upon success, a negative error code otherwise. */ 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. + * @return SP_OK upon success, a negative error code otherwise. */ enum sp_return sp_close(struct sp_port *port); +/** + * Get the name of a port. + * + * The name returned is whatever is normally used to refer to a port on the + * current operating system; e.g. for Windows it will usually be a "COMn" + * device name, and for Unix it will be a device path beginning with "/dev/". + * + * @param port Pointer to port structure. + * + * @return The port name, or NULL if an invalid port is passed. The name + * string is part of the port structure and may not be used after the + * port structure has been freed. + */ +char *sp_get_port_name(const struct sp_port *port); + +/** + * Get the operating system handle for a port. + * + * The type of the handle depends on the operating system. On Unix based + * systems, the handle is a file descriptor of type "int". On Windows, the + * handle is of type "HANDLE". The user should allocate a variable of the + * appropriate type and pass a pointer to this to receive the result. + * + * To obtain a valid handle, the port must first be opened by calling + * sp_open() using the same port structure. + * + * After the port is closed or the port structure freed, the handle may + * no longer be valid. + * + * @warning This feature is provided so that programs may make use of + * OS-specific functionality where desired. Doing so obviously + * comes at a cost in portability. It also cannot be guaranteed + * that direct usage of the OS handle will not conflict with the + * library's own usage of the port. Be careful. + * + * @return SP_OK upon success, a negative error code otherwise. + */ +enum sp_return sp_get_port_handle(const struct sp_port *port, void *result_ptr); + /** * @} * @defgroup Configuration Setting port parameters * @{ */ +/** + * Allocate a port configuration structure. + * + * The user should allocate a variable of type "struct sp_config *" and pass a + * pointer to this to receive the result. The variable will be updated to + * point to the new configuration structure. The structure is opaque and must + * be accessed via the functions provided. + * + * All parameters in the structure will be initialised to special values which + * are ignored by sp_set_config(). + * + * The structure should be freed after use by calling sp_free_config(). + * + * @param config_ptr Pointer to variable to receive result. + * + * @return SP_OK upon success, a negative error code otherwise. + */ +enum sp_return sp_new_config(struct sp_port_config **config_ptr); + +/** + * Free a port configuration structure. + * + * @param config Pointer to configuration structure. + */ +void sp_free_config(struct sp_port_config *config); + /** * 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. + * The user should allocate a configuration structure using sp_new_config() + * and pass this as the config parameter. The configuration structure will + * be updated 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. + * Any parameters that are configured with settings not recognised or + * supported by libserialport, will be set to special values that are + * ignored by sp_set_config(). * - * @return SP_OK on success, SP_ERR_FAIL on failure, or SP_ERR_ARG - * for invalid arguments. + * @return SP_OK upon success, a negative error code otherwise. */ 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. + * For each parameter in the configuration, there is a special value (usually + * -1, but see the documentation for each field). These values will be ignored + * and the corresponding setting left unchanged on the port. * - * @return SP_OK on success, SP_ERR_FAIL on failure, or SP_ERR_ARG - * for invalid arguments. + * @return SP_OK upon success, a negative error code otherwise. */ enum sp_return sp_set_config(struct sp_port *port, const struct sp_port_config *config); @@ -392,115 +426,327 @@ enum sp_return sp_set_config(struct sp_port *port, const struct sp_port_config * * @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. + * @return SP_OK upon success, a negative error code otherwise. */ enum sp_return sp_set_baudrate(struct sp_port *port, int baudrate); /** - * Set the number of data bits for the specified serial port. + * Get the baud rate from a port configuration. + * + * The user should allocate a variable of type int and pass a pointer to this + * to receive the result. + * + * @param config Pointer to configuration structure. + * @param baudrate_ptr Pointer to variable to store result. + * + * @return SP_OK upon success, a negative error code otherwise. + */ +enum sp_return sp_get_config_baudrate(const struct sp_port_config *config, int *baudrate_ptr); + +/** + * Set the baud rate in a port configuration. + * + * @param config Pointer to configuration structure. + * @param baudrate Baud rate in bits per second, or -1 to retain current setting. + * + * @return SP_OK upon success, a negative error code otherwise. + */ +enum sp_return sp_set_config_baudrate(struct sp_port_config *config, int baudrate); + +/** + * Set the 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. + * @param bits Number of data bits. * - * @return SP_OK on success, SP_ERR_FAIL on failure, or SP_ERR_ARG - * for invalid arguments. + * @return SP_OK upon success, a negative error code otherwise. */ enum sp_return sp_set_bits(struct sp_port *port, int bits); /** - * Set the parity for the specified serial port. + * Get the data bits from a port configuration. + * + * The user should allocate a variable of type int and pass a pointer to this + * to receive the result. + * + * @param config Pointer to configuration structure. + * @param bits_ptr Pointer to variable to store result. + * + * @return SP_OK upon success, a negative error code otherwise. + */ +enum sp_return sp_get_config_bits(const struct sp_port_config *config, int *bits_ptr); + +/** + * Set the data bits in a port configuration. + * + * @param config Pointer to configuration structure. + * @param bits Number of data bits, or -1 to retain current setting. + * + * @return SP_OK upon success, a negative error code otherwise. + */ +enum sp_return sp_set_config_bits(struct sp_port_config *config, int bits); + +/** + * Set the parity setting for the specified serial port. * * @param port Pointer to port structure. - * @param parity Parity setting to use. + * @param parity Parity setting. * - * @return SP_OK on success, SP_ERR_FAIL on failure, or SP_ERR_ARG - * for invalid arguments. + * @return SP_OK upon success, a negative error code otherwise. */ enum sp_return sp_set_parity(struct sp_port *port, enum sp_parity parity); /** - * Set the number of stop bits for the specified port. + * Get the parity setting from a port configuration. + * + * The user should allocate a variable of type enum sp_parity and pass a pointer to this + * to receive the result. + * + * @param config Pointer to configuration structure. + * @param parity_ptr Pointer to variable to store result. + * + * @return SP_OK upon success, a negative error code otherwise. + */ +enum sp_return sp_get_config_parity(const struct sp_port_config *config, enum sp_parity *parity_ptr); + +/** + * Set the parity setting in a port configuration. + * + * @param config Pointer to configuration structure. + * @param parity Parity setting, or -1 to retain current setting. + * + * @return SP_OK upon success, a negative error code otherwise. + */ +enum sp_return sp_set_config_parity(struct sp_port_config *config, enum sp_parity parity); + +/** + * Set the stop bits for the specified serial port. * * @param port Pointer to port structure. - * @param stopbits Number of stop bits to use (1 or 2). + * @param stopbits Number of stop bits. * - * @return SP_OK on success, SP_ERR_FAIL on failure, or SP_ERR_ARG - * for invalid arguments. + * @return SP_OK upon success, a negative error code otherwise. */ enum sp_return sp_set_stopbits(struct sp_port *port, int stopbits); /** - * Set the flow control type for the specified serial port. + * Get the stop bits from a port configuration. * - * 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. + * The user should allocate a variable of type int and pass a pointer to this + * to receive the result. * - * @param port Pointer to port structure. - * @param flowcontrol Flow control setting to use. + * @param config Pointer to configuration structure. + * @param stopbits_ptr Pointer to variable to store result. * - * @return SP_OK on success, SP_ERR_FAIL on failure, or SP_ERR_ARG - * for invalid arguments. + * @return SP_OK upon success, a negative error code otherwise. */ -enum sp_return sp_set_flowcontrol(struct sp_port *port, enum sp_flowcontrol flowcontrol); +enum sp_return sp_get_config_stopbits(const struct sp_port_config *config, int *stopbits_ptr); + +/** + * Set the stop bits in a port configuration. + * + * @param config Pointer to configuration structure. + * @param stopbits Number of stop bits, or -1 to retain current setting. + * + * @return SP_OK upon success, a negative error code otherwise. + */ +enum sp_return sp_set_config_stopbits(struct sp_port_config *config, int stopbits); /** - * Set the RTS pin behaviour for the specified port. + * Set the RTS pin behaviour for the specified serial 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. + * @return SP_OK upon success, a negative error code otherwise. */ enum sp_return sp_set_rts(struct sp_port *port, enum sp_rts rts); /** - * Set the CTS pin behaviour for the specified port. + * Get the RTS pin behaviour from a port configuration. + * + * The user should allocate a variable of type enum sp_rts and pass a pointer to this + * to receive the result. + * + * @param config Pointer to configuration structure. + * @param rts_ptr Pointer to variable to store result. + * + * @return SP_OK upon success, a negative error code otherwise. + */ +enum sp_return sp_get_config_rts(const struct sp_port_config *config, enum sp_rts *rts_ptr); + +/** + * Set the RTS pin behaviour in a port configuration. + * + * @param config Pointer to configuration structure. + * @param rts RTS pin mode, or -1 to retain current setting. + * + * @return SP_OK upon success, a negative error code otherwise. + */ +enum sp_return sp_set_config_rts(struct sp_port_config *config, enum sp_rts rts); + +/** + * Set the CTS pin behaviour for the specified serial 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. + * @return SP_OK upon success, a negative error code otherwise. */ enum sp_return sp_set_cts(struct sp_port *port, enum sp_cts cts); /** - * Set the DTR pin behaviour for the specified port. + * Get the CTS pin behaviour from a port configuration. + * + * The user should allocate a variable of type enum sp_cts and pass a pointer to this + * to receive the result. + * + * @param config Pointer to configuration structure. + * @param cts_ptr Pointer to variable to store result. + * + * @return SP_OK upon success, a negative error code otherwise. + */ +enum sp_return sp_get_config_cts(const struct sp_port_config *config, enum sp_cts *cts_ptr); + +/** + * Set the CTS pin behaviour in a port configuration. + * + * @param config Pointer to configuration structure. + * @param cts CTS pin mode, or -1 to retain current setting. + * + * @return SP_OK upon success, a negative error code otherwise. + */ +enum sp_return sp_set_config_cts(struct sp_port_config *config, enum sp_cts cts); + +/** + * Set the DTR pin behaviour for the specified serial 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. + * @return SP_OK upon success, a negative error code otherwise. */ enum sp_return sp_set_dtr(struct sp_port *port, enum sp_dtr dtr); /** - * Set the RTS pin behaviour for the specified port. + * Get the DTR pin behaviour from a port configuration. + * + * The user should allocate a variable of type enum sp_dtr and pass a pointer to this + * to receive the result. + * + * @param config Pointer to configuration structure. + * @param dtr_ptr Pointer to variable to store result. + * + * @return SP_OK upon success, a negative error code otherwise. + */ +enum sp_return sp_get_config_dtr(const struct sp_port_config *config, enum sp_dtr *dtr_ptr); + +/** + * Set the DTR pin behaviour in a port configuration. + * + * @param config Pointer to configuration structure. + * @param dtr DTR pin mode, or -1 to retain current setting. + * + * @return SP_OK upon success, a negative error code otherwise. + */ +enum sp_return sp_set_config_dtr(struct sp_port_config *config, enum sp_dtr dtr); + +/** + * Set the DSR pin behaviour for the specified serial 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. + * @return SP_OK upon success, a negative error code otherwise. */ enum sp_return sp_set_dsr(struct sp_port *port, enum sp_dsr dsr); /** - * Configure XON/XOFF flow control for the specified port. + * Get the DSR pin behaviour from a port configuration. + * + * The user should allocate a variable of type enum sp_dsr and pass a pointer to this + * to receive the result. + * + * @param config Pointer to configuration structure. + * @param dsr_ptr Pointer to variable to store result. + * + * @return SP_OK upon success, a negative error code otherwise. + */ +enum sp_return sp_get_config_dsr(const struct sp_port_config *config, enum sp_dsr *dsr_ptr); + +/** + * Set the DSR pin behaviour in a port configuration. + * + * @param config Pointer to configuration structure. + * @param dsr DSR pin mode, or -1 to retain current setting. + * + * @return SP_OK upon success, a negative error code otherwise. + */ +enum sp_return sp_set_config_dsr(struct sp_port_config *config, enum sp_dsr dsr); + +/** + * Set the XON/XOFF configuration for the specified serial port. * * @param port Pointer to port structure. - * @param xon_xoff XON/XOFF flow control mode. + * @param xon_xoff XON/XOFF mode. * - * @return SP_OK on success, SP_ERR_FAIL on failure, or SP_ERR_ARG - * for invalid arguments. + * @return SP_OK upon success, a negative error code otherwise. */ enum sp_return sp_set_xon_xoff(struct sp_port *port, enum sp_xonxoff xon_xoff); +/** + * Get the XON/XOFF configuration from a port configuration. + * + * The user should allocate a variable of type enum sp_xonxoff and pass a pointer to this + * to receive the result. + * + * @param config Pointer to configuration structure. + * @param xon_xoff_ptr Pointer to variable to store result. + * + * @return SP_OK upon success, a negative error code otherwise. + */ +enum sp_return sp_get_config_xon_xoff(const struct sp_port_config *config, enum sp_xonxoff *xon_xoff_ptr); + +/** + * Set the XON/XOFF configuration in a port configuration. + * + * @param config Pointer to configuration structure. + * @param xon_xoff XON/XOFF mode, or -1 to retain current setting. + * + * @return SP_OK upon success, a negative error code otherwise. + */ +enum sp_return sp_set_config_xon_xoff(struct sp_port_config *config, enum sp_xonxoff xon_xoff); + +/** + * Set the flow control type in a port configuration. + * + * 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. + * + * @param config Pointer to configuration structure. + * @param flowcontrol Flow control setting to use. + * + * @return SP_OK upon success, a negative error code otherwise. + */ +enum sp_return sp_set_config_flowcontrol(struct sp_port_config *config, enum sp_flowcontrol flowcontrol); + +/** + * 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. + * + * @param port Pointer to port structure. + * @param flowcontrol Flow control setting to use. + * + * @return SP_OK upon success, a negative error code otherwise. + */ +enum sp_return sp_set_flowcontrol(struct sp_port *port, enum sp_flowcontrol flowcontrol); + /** * @} * @defgroup Data Reading, writing, and flushing data @@ -518,8 +764,7 @@ enum sp_return sp_set_xon_xoff(struct sp_port *port, enum sp_xonxoff xon_xoff); * @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. + * @return The number of bytes read on success, or a negative error code. */ enum sp_return sp_read(struct sp_port *port, void *buf, size_t count); @@ -534,8 +779,7 @@ enum sp_return sp_read(struct sp_port *port, void *buf, size_t count); * @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. + * @return The number of bytes written on success, or a negative error code. */ enum sp_return sp_write(struct sp_port *port, const void *buf, size_t count); @@ -545,8 +789,7 @@ enum sp_return sp_write(struct sp_port *port, const void *buf, size_t count); * @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. + * @return SP_OK upon success, a negative error code otherwise. */ enum sp_return sp_flush(struct sp_port *port, enum sp_buffer buffers); @@ -555,14 +798,13 @@ enum sp_return sp_flush(struct sp_port *port, enum sp_buffer buffers); * * @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. + * @return SP_OK upon success, a negative error code otherwise. */ enum sp_return sp_drain(struct sp_port *port); /** * @} - * @defgroup Signal Port signalling operations + * @defgroup Signals Port signalling operations * @{ */ @@ -577,8 +819,7 @@ enum sp_return sp_drain(struct sp_port *port); * @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. + * @return SP_OK upon success, a negative error code otherwise. */ enum sp_return sp_get_signals(struct sp_port *port, enum sp_signal *signals); @@ -587,8 +828,7 @@ enum sp_return sp_get_signals(struct sp_port *port, enum sp_signal *signals); * * @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. + * @return SP_OK upon success, a negative error code otherwise. */ enum sp_return sp_start_break(struct sp_port *port); @@ -597,8 +837,7 @@ enum sp_return sp_start_break(struct sp_port *port); * * @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. + * @return SP_OK upon success, a negative error code otherwise. */ enum sp_return sp_end_break(struct sp_port *port); @@ -636,6 +875,29 @@ char *sp_last_error_message(void); */ void sp_free_error_message(char *message); +/** + * Set the handler function for library debugging messages. + * + * Debugging messages are generated by the library during each operation, + * to help in diagnosing problems. The handler will be called for each + * message. The handler can be set to NULL to ignore all debug messages. + * + * The handler function should accept a format string and variable length + * argument list, in the same manner as e.g. printf(). + * + * The default handler is sp_default_debug_handler(). + */ +void sp_set_debug_handler(void (*handler)(const char *format, ...)); + +/** + * Default handler function for library debugging messages. + * + * This function prints debug messages to the standard error stream if the + * environment variable LIBSERIALPORT_DEBUG is set. Otherwise, they are + * ignored. + */ +void sp_default_debug_handler(const char *format, ...); + /** @} */ #ifdef __cplusplus