line-range.h

   1 #ifndef LINE_RANGE_H
   2 #define LINE_RANGE_H
   3
   4 struct index_state;
   5
   6 /*
   7  * Parse one item in an -L begin,end option w.r.t. the notional file
   8  * object 'cb_data' consisting of 'lines' lines.
   9  *
  10  * The 'nth_line_cb' callback is used to determine the start of the
  11  * line 'lno' inside the 'cb_data'.  The caller is expected to already
  12  * have a suitable map at hand to make this a constant-time lookup.
  13  *
  14  * 'anchor' is the 1-based line at which relative range specifications
  15  * should be anchored. Absolute ranges are unaffected by this value.
  16  *
  17  * Returns 0 in case of success and -1 if there was an error.  The
  18  * actual range is stored in *begin and *end.  The counting starts
  19  * at 1!  In case of error, the caller should show usage message.
  20  */
  21
  22 typedef const char *(*nth_line_fn_t)(void *data, long lno);
  23
  24 int parse_range_arg(const char *arg,
  25                     nth_line_fn_t nth_line_cb,
  26                     void *cb_data, long lines, long anchor,
  27                     long *begin, long *end,
  28                     const char *path, struct index_state *istate);
  29
  30 /*
  31  * Scan past a range argument that could be parsed by
  32  * 'parse_range_arg', to help the caller determine the start of the
  33  * filename in '-L n,m:file' syntax.
  34  *
  35  * Returns a pointer to the first character after the 'n,m' part, or
  36  * NULL in case the argument is obviously malformed.
  37  */
  38
  39 const char *skip_range_arg(const char *arg, struct index_state *istate);
  40
  41 #endif /* LINE_RANGE_H */