xdiff-interface.h

   1 #ifndef XDIFF_INTERFACE_H
   2 #define XDIFF_INTERFACE_H
   3
   4 #include "cache.h"
   5 #include "xdiff/xdiff.h"
   6
   7 /*
   8  * xdiff isn't equipped to handle content over a gigabyte;
   9  * we make the cutoff 1GB - 1MB to give some breathing
  10  * room for constant-sized additions (e.g., merge markers)
  11  */
  12 #define MAX_XDIFF_SIZE (1024UL * 1024 * 1023)
  13
  14 /**
  15  * The `xdiff_emit_line_fn` function can return 1 to abort early, or 0
  16  * to continue processing. Note that doing so is an all-or-nothing
  17  * affair, as returning 1 will return all the way to the top-level,
  18  * e.g. the xdi_diff_outf() call to generate the diff.
  19  *
  20  * Thus returning 1 means you won't be getting any more diff lines. If
  21  * you need something in-between those two options you'll to use
  22  * `xdl_emit_hunk_consume_func_t` and implement your own version of
  23  * xdl_emit_diff().
  24  *
  25  * We may extend the interface in the future to understand other more
  26  * granular return values. While you should return 1 to exit early,
  27  * doing so will currently make your early return indistinguishable
  28  * from an error internal to xdiff, xdiff itself will see that
  29  * non-zero return and translate it to -1.
  30  *
  31  * See "diff_grep" in diffcore-pickaxe.c for a trick to work around
  32  * this, i.e. using the "consume_callback_data" to note the desired
  33  * early return.
  34  */
  35 typedef int (*xdiff_emit_line_fn)(void *, char *, unsigned long);
  36 typedef void (*xdiff_emit_hunk_fn)(void *data,
  37                                    long old_begin, long old_nr,
  38                                    long new_begin, long new_nr,
  39                                    const char *func, long funclen);
  40
  41 int xdi_diff(mmfile_t *mf1, mmfile_t *mf2, xpparam_t const *xpp, xdemitconf_t const *xecfg, xdemitcb_t *ecb);
  42 int xdi_diff_outf(mmfile_t *mf1, mmfile_t *mf2,
  43                   xdiff_emit_hunk_fn hunk_fn,
  44                   xdiff_emit_line_fn line_fn,
  45                   void *consume_callback_data,
  46                   xpparam_t const *xpp, xdemitconf_t const *xecfg);
  47 int read_mmfile(mmfile_t *ptr, const char *filename);
  48 void read_mmblob(mmfile_t *ptr, const struct object_id *oid);
  49 int buffer_is_binary(const char *ptr, unsigned long size);
  50
  51 void xdiff_set_find_func(xdemitconf_t *xecfg, const char *line, int cflags);
  52 void xdiff_clear_find_func(xdemitconf_t *xecfg);
  53 int git_xmerge_config(const char *var, const char *value, void *cb);
  54 extern int git_xmerge_style;
  55
  56 /*
  57  * Compare the strings l1 with l2 which are of size s1 and s2 respectively.
  58  * Returns 1 if the strings are deemed equal, 0 otherwise.
  59  * The `flags` given as XDF_WHITESPACE_FLAGS determine how white spaces
  60  * are treated for the comparison.
  61  */
  62 int xdiff_compare_lines(const char *l1, long s1,
  63                         const char *l2, long s2, long flags);
  64
  65 /*
  66  * Returns a hash of the string s of length len.
  67  * The `flags` given as XDF_WHITESPACE_FLAGS determine how white spaces
  68  * are treated for the hash.
  69  */
  70 unsigned long xdiff_hash_string(const char *s, size_t len, long flags);
  71
  72 #endif