* 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.
+ * All functions can return only four possible error values:
*
- * 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.
+ * - @ref SP_ERR_ARG means that a function was called with invalid
+ * arguments. This implies a bug in the caller. The arguments passed would
+ * be invalid regardless of the underlying OS or serial device involved.
+ *
+ * - @ref SP_ERR_FAIL means that the OS reported a failure. The error code or
+ * message provided by the OS can be obtained by calling sp_last_error_code()
+ * or sp_last_error_message().
+ *
+ * - @ref SP_ERR_SUPP indicates that there is no support for the requested
+ * operation in the current OS, driver or device. No error message is
+ * available from the OS in this case. There is either no way to request
+ * the operation in the first place, or libserialport does not know how to
+ * do so in the current version.
+ *
+ * - @ref SP_ERR_MEM indicates that a memory allocation failed.
+ *
+ * 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.
SP_ERR_FAIL = -2,
/** A memory allocation failed while executing the operation. */
SP_ERR_MEM = -3,
+ /** The requested operation is not supported by this system or device. */
+ SP_ERR_SUPP = -4,
};
/** Port access modes. */
};
/** 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 {
*
* 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);
+/**
+ * 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);
+
/**
* Free a port structure obtained from sp_get_port_by_name() or sp_copy_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);
*
* 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);
* @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);
* 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.
+ * @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);
*
* 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.
+ * @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);
* @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);
* @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.
+ * @return SP_OK upon success, a negative error code otherwise.
*/
enum sp_return sp_set_bits(struct sp_port *port, int bits);
* @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.
+ * @return SP_OK upon success, a negative error code otherwise.
*/
enum sp_return sp_set_parity(struct sp_port *port, enum sp_parity parity);
* @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.
+ * @return SP_OK upon success, a negative error code otherwise.
*/
enum sp_return sp_set_stopbits(struct sp_port *port, int stopbits);
* @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.
+ * @return SP_OK upon success, a negative error code otherwise.
*/
enum sp_return sp_set_flowcontrol(struct sp_port *port, enum sp_flowcontrol flowcontrol);
* @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);
* @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);
* @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);
* @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);
* @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.
+ * @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);
* @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);
* @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);
* @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);
*
* @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);
* @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);
*
* @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);
*
* @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);
*/
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
projects / libserialport.git / blobdiff