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 an open
-port. This structure should be allocated by the user and is populated by
-sp_open(). It can be freed safely after sp_close().
+Most functions take a pointer to a struct sp_port, which represents an serial
+port. This structure is obtained from the array returned by sp_list_ports().
All functions can return only three possible error values. SP_ERR_ARG indicates
the function was called with invalid arguments. SP_ERR_FAIL indicates that the
Enumeration
-----------
-char **sp_list_ports();
+struct sp_port **sp_list_ports();
Lists the serial ports available on the system. The value returned is an array
- of port names as C strings, terminated by a NULL. It should be freed after use
- by calling sp_free_port_list().
+ of pointers to sp_port structures, terminated by a NULL. It should be freed after
+ use by calling sp_free_port_list().
-void sp_free_port_list(char **list);
+void sp_free_port_list(struct sp_port **list);
Frees the data structure returned by sp_list_ports().
Opening and closing ports
-------------------------
-int sp_open(struct sp_port *port, char *portname, int flags);
+int sp_open(struct sp_port *port, int flags);
Opens the specified serial port.
Parameters:
- port: Pointer to empty port structure, allocated by caller.
- portname: Name of port to open.
+ port: Pointer to port structure.
flags: Flags to use when opening the serial port. Possible
flags are: SP_MODE_RDWR, SP_MODE_RDONLY, and SP_MODE_NONBLOCK.
#include "serialport.h"
-static char **sp_list_append(char **list, void *data, size_t len)
+static struct sp_port *sp_port_new(char *portname, size_t len)
+{
+ struct sp_port *port;
+
+ if (!(port = malloc(sizeof(struct sp_port))))
+ return NULL;
+
+ if (!(port->name = malloc(len)))
+ {
+ free(port);
+ return NULL;
+ }
+
+ memcpy(port->name, portname, len);
+
+ return port;
+}
+
+static struct sp_port **sp_list_append(struct sp_port **list, char *portname, size_t len)
{
void *tmp;
unsigned int count;
for (count = 0; list[count]; count++);
- if (!(tmp = realloc(list, sizeof(char *) * (count + 2))))
+ if (!(tmp = realloc(list, sizeof(struct sp_port *) * (count + 2))))
goto fail;
list = tmp;
- if (!(list[count] = malloc(len)))
+ if (!(list[count] = sp_port_new(portname, len)))
goto fail;
- memcpy(list[count], data, len);
list[count + 1] = NULL;
return list;
fail:
*
* @return A null-terminated array of port name strings.
*/
-char **sp_list_ports(void)
+struct sp_port **sp_list_ports(void)
{
- char **list;
+ struct sp_port **list;
- if (!(list = malloc(sizeof(char *))))
+ if (!(list = malloc(sizeof(struct sp_port **))))
return NULL;
list[0] = NULL;
/**
* Free a port list returned by sp_list_ports.
*/
-void sp_free_port_list(char **list)
+void sp_free_port_list(struct sp_port **list)
{
unsigned int i;
for (i = 0; list[i]; i++)
* @return SP_OK on success, SP_ERR_FAIL on failure,
* or SP_ERR_ARG if an invalid port or name is passed.
*/
-int sp_open(struct sp_port *port, char *portname, int flags)
+int sp_open(struct sp_port *port, int flags)
{
if (!port)
return SP_ERR_ARG;
- if (!portname)
- return SP_ERR_ARG;
-
- port->name = portname;
-
#ifdef _WIN32
DWORD desired_access = 0, flags_and_attributes = 0;
/* Map 'flags' to the OS-specific settings. */
SP_FLOW_SOFTWARE = 2
};
-char **sp_list_ports(void);
-void sp_free_port_list(char **ports);
-int sp_open(struct sp_port *port, char *portname, int flags);
+struct sp_port **sp_list_ports(void);
+void sp_free_port_list(struct sp_port **ports);
+int sp_open(struct sp_port *port, int flags);
int sp_close(struct sp_port *port);
int sp_flush(struct sp_port *port);
int sp_write(struct sp_port *port, const void *buf, size_t count);