Add 'df_name_compare()' helper function

This new helper is identical to base_name_compare(), except it compares conflicting directory/file entries as equal in order to help handling DF conflicts (thus the name). Note that while a directory name compares as equal to a regular file with the new helper, they then individually compare _differently_ to a filename that has a dot after the basename (because '\0' < '.' < '/'). So a directory called "foo/" will compare equal to a file "foo", even though "foo.c" will compare after "foo" and before "foo/" This will be used by routines that want to traverse the git namespace but then handle conflicting entries together when possible. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Linus Torvalds committed Mar 5, 2008 at 18:25 UTC 0ab9e1e8cdaefdd33bf24bb0be0ec766483f8bbe

2 files changed +36

cache.h

@@ -536,6 +536,7 @@ extern int create_symref(const char *ref, const char *refs_heads_master, const c

536 extern int validate_headref(const char *ref);

537

538 extern int base_name_compare(const char *name1, int len1, int mode1, const char *name2, int len2, int mode2);

539 +extern int df_name_compare(const char *name1, int len1, int mode1, const char *name2, int len2, int mode2);

540 extern int cache_name_compare(const char *name1, int len1, const char *name2, int len2);

541

542 extern void *read_object_with_reference(const unsigned char *sha1,

read-cache.c

+35

@@ -351,6 +351,41 @@ int base_name_compare(const char *name1, int len1, int mode1,

351 return (c1 < c2) ? -1 : (c1 > c2) ? 1 : 0;

352 }

353

354 +/*

355 + * df_name_compare() is identical to base_name_compare(), except it

356 + * compares conflicting directory/file entries as equal. Note that

357 + * while a directory name compares as equal to a regular file, they

358 + * then individually compare _differently_ to a filename that has

359 + * a dot after the basename (because '\0' < '.' < '/').

360 + *

361 + * This is used by routines that want to traverse the git namespace

362 + * but then handle conflicting entries together when possible.

363 + */

364 +int df_name_compare(const char *name1, int len1, int mode1,

365 + const char *name2, int len2, int mode2)

366 +{

367 + int len = len1 < len2 ? len1 : len2, cmp;

368 + unsigned char c1, c2;

369 +

370 + cmp = memcmp(name1, name2, len);

371 + if (cmp)

372 + return cmp;

373 + /* Directories and files compare equal (same length, same name) */

374 + if (len1 == len2)

375 + return 0;

376 + c1 = name1[len];

377 + if (!c1 && S_ISDIR(mode1))

378 + c1 = '/';

379 + c2 = name2[len];

380 + if (!c2 && S_ISDIR(mode2))

381 + c2 = '/';

382 + if (c1 == '/' && !c2)

383 + return 0;

384 + if (c2 == '/' && !c1)

385 + return 0;

386 + return c1 - c2;

387 +}

388 +

389 int cache_name_compare(const char *name1, int flags1, const char *name2, int flags2)

390 {

391 int len1 = flags1 & CE_NAMEMASK;