1#ifndef LINE_RANGE_H 2#define LINE_RANGE_H 3 4/* 5 * Parse one item in an -L begin,end option w.r.t. the notional file 6 * object 'cb_data' consisting of 'lines' lines. 7 * 8 * The 'nth_line_cb' callback is used to determine the start of the 9 * line 'lno' inside the 'cb_data'. The caller is expected to already 10 * have a suitable map at hand to make this a constant-time lookup. 11 * 12 * Returns 0 in case of success and -1 if there was an error. The 13 * actual range is stored in *begin and *end. The counting starts 14 * at 1! In case of error, the caller should show usage message. 15 */ 16 17typedef const char *(*nth_line_fn_t)(void *data, long lno); 18 19extern int parse_range_arg(const char *arg, 20 nth_line_fn_t nth_line_cb, 21 void *cb_data, long lines, 22 long *begin, long *end); 23 24/* 25 * Scan past a range argument that could be parsed by 26 * 'parse_range_arg', to help the caller determine the start of the 27 * filename in '-L n,m:file' syntax. 28 * 29 * Returns a pointer to the first character after the 'n,m' part, or 30 * NULL in case the argument is obviously malformed. 31 */ 32 33extern const char *skip_range_arg(const char *arg); 34 35#endif /* LINE_RANGE_H */