libnd_misc 3 LIBNETDUDE Library libnd_misc guint libnd_misc_writen (int fd, const guchar *data, guint size); guint libnd_misc_readn (int fd, guchar *data, guint size); guint libnd_misc_readline (int fd, guchar *data, guint size); int libnd_misc_ones_complement_checksum (const void *data, int data_len, u_int32_t sum); u_short libnd_misc_in_cksum (u_short *addr, int addr_len, u_int preadd); gboolean libnd_misc_exists (const char *filename); gboolean libnd_misc_can_read (const char *filename); gboolean libnd_misc_can_write (const char *filename); gboolean libnd_misc_is_tcpdump_file (const char *filename); gboolean libnd_misc_can_exec (const char *filename); gboolean libnd_misc_is_dir (const char *filename); gint libnd_misc_int_cmp (gconstpointer int1, gconstpointer int2); char* libnd_misc_add_slash (char *filename); GList* libnd_misc_get_if_names (int flags); int libnd_misc_get_if_mtu (const char *ifname); void libnd_misc_get_hardware_string (char *str, guint str_len, guchar *address, guint addr_len); char* libnd_misc_get_unnamed_string (void); char* libnd_misc_timeval_to_string (struct bpf_timeval *tv); guchar* libnd_misc_memdup (const guchar *data, guint data_len); void libnd_misc_ctime (const struct bpf_timeval *tv, char *buf, int buflen, gboolean fix_gmt, gboolean add_usec); int libnd_misc_get_gmt_deviation (void); char* libnd_misc_get_tmpfile (const char *filename); libnd_misc_writenguint libnd_misc_writen (int fd, const guchar *data, guint size); The function tries to write n buffers to the given file descriptor. fd : file descriptor data : data buffer size : size of buffer Returns : number of bytes written, or value < 0 on error. libnd_misc_readnguint libnd_misc_readn (int fd, guchar *data, guint size); The function tries to read n buffers from the given file descriptor. fd : file descriptor data : data buffer size : size of buffer Returns : number of bytes read, or value < 0 on error. libnd_misc_readlineguint libnd_misc_readline (int fd, guchar *data, guint size); The function reads from a file descriptor until a newline is encountered. WARNING -- this function can BLOCK. fd : file descriptor data : data buffer size : size of buffer Returns : number of bytes read. libnd_misc_ones_complement_checksumint libnd_misc_ones_complement_checksum (const void *data, int data_len, u_int32_t sum); The function computes the ones-complement checksum of the data pointed to by data. If you want to extend the checksum over data areas not included in data, you can pre-add the sum of that data in units of short ints (16bit) and pass it as sum. data : pointer to data to checksum. data_len : length of data. sum : pre-added input. Returns : checksum. libnd_misc_in_cksumu_short libnd_misc_in_cksum (u_short *addr, int addr_len, u_int preadd); The function computes the Internet checksum of addr. Other data can be included in the checksum by pre-added the sum if that data in units of short ints (16bit) and passing it as preadd. addr : data to checksum. addr_len : length of addr data. preadd : pre-added input. Returns : checksum. libnd_misc_existsgboolean libnd_misc_exists (const char *filename); The function checks whether filename exists and returns the result. filename : name of file. Returns : TRUE when filename exists, FALSE otherwise. libnd_misc_can_readgboolean libnd_misc_can_read (const char *filename); The function checks whether filename can be read and returns the result. filename : name of file. Returns : TRUE if file is readable, FALSE if it is not or if there is another error (such as filename doesn't exist). libnd_misc_can_writegboolean libnd_misc_can_write (const char *filename); The function checks whether filename can be written to and returns the result. filename : name of file. Returns : TRUE if file is writeable, FALSE if it is not or if there is another error (such as filename doesn't exist). libnd_misc_is_tcpdump_filegboolean libnd_misc_is_tcpdump_file (const char *filename); The function checks whether filename is a tcpdump savefile by looking for tcpdump's magic 0xa1b2c3d4 and its variations. filename : name of file. Returns : TRUE if test was positive, FALSE otherwise or if there was an error. libnd_misc_can_execgboolean libnd_misc_can_exec (const char *filename); The function checks whether filename can be executed and returns the result. filename : name of file. Returns : TRUE if file is executable, FALSE if it is not or if there is another error (such as filename doesn't exist). libnd_misc_is_dirgboolean libnd_misc_is_dir (const char *filename); The function checks whether filename is a directory and returns the result. filename : name of file. Returns : TRUE if file is a directory, FALSE if it is not or if there is another error (such as filename doesn't exist). libnd_misc_int_cmpgint libnd_misc_int_cmp (gconstpointer int1, gconstpointer int2); This is a simple compare function for pointers that can be casted (not dereferenced!) to ints, returning -1/0/1 of row1 is smaller/ equal/larger than row2. The signature allows usage with various glib functions. int1 : pointer using integer value. int2 : pointer using integer value. Returns : comparison result. libnd_misc_add_slashchar* libnd_misc_add_slash (char *filename); The function checks if filename ends with a slash and if not, reallocs the memory filename uses and appends a slash. filename : filename to test. Returns : resulting string. libnd_misc_get_if_namesGList* libnd_misc_get_if_names (int flags); The function returns an alphabetically ordered glib list of strings containing the names of those network interfaces that satisfy the given flag combination. flags : flags the interface must have set (IFF_xxx values, see net/if.h). Returns : list of strings. You need to free this list and its entries if you don't need the result any more. libnd_misc_get_if_mtuint libnd_misc_get_if_mtu (const char *ifname); The function returns the MTU for a given interface. I have no idea whether this compiles on anything non-Linux ... ifname : name of interface to query. Returns : libnd_misc_get_hardware_stringvoid libnd_misc_get_hardware_string (char *str, guint str_len, guchar *address, guint addr_len); The function places into the space pointed to by str a string representing the hardware address as "xx : xx : ... : xx". str : pointer to space filled with string. str_len : available string length. address : hardware address data. addr_len : length of hardware address in bytes. libnd_misc_get_unnamed_stringchar* libnd_misc_get_unnamed_string (void); The function returns a pointer to statically allocated data that gets filled with a numbered dummy file name. You need to strdup() the pointer if you want to keep it around. Returns : new filename. libnd_misc_timeval_to_stringchar* libnd_misc_timeval_to_string (struct bpf_timeval *tv); The function returns a static string representing tv as a time interval in the form of, for example, "2 days, 15:26:32:978560". tv : timeval to print string for. Returns : ASCII version of time interval tv. libnd_misc_memdupguchar* libnd_misc_memdup (const guchar *data, guint data_len); The function allocates a chunk of memory of size data_len, and then copies data_len bytes over from data into the newly allocated memory region. data : input data. data_len : number of bytes to copy. Returns : new memory chunk, or NULL if allocation failed. libnd_misc_ctimevoid libnd_misc_ctime (const struct bpf_timeval *tv, char *buf, int buflen, gboolean fix_gmt, gboolean add_usec); The function is similar to ctime_r(3). fix_gmt includes the local divergence from GMT, and add_usec includes the microseconds in the timestamp. tv : timestamp to convert. buf : buffer to hold result. buflen : length of buf in bytes. fix_gmt : whether to keep time local or make it relative to GMT. add_usec : whether to include the microseconds of tv in the output. libnd_misc_get_gmt_deviationint libnd_misc_get_gmt_deviation (void); The function returns the number of seconds our local time deviates from GMT. Returns : deviation in seconds. libnd_misc_get_tmpfilechar* libnd_misc_get_tmpfile (const char *filename); filename : Returns :