Revision 1335d76e4569fa84e52dc24c88c04daeae6e160e authored by Junio C Hamano on 08 July 2016, 17:59:15 UTC, committed by Junio C Hamano on 12 July 2016, 20:06:43 UTC
When merge_recursive() decides what the correct blob object merge
result for a path should be, it uses update_file_flags() helper
function to write it out to a working tree file and then calls
add_cacheinfo().  The add_cacheinfo() function in turn calls
make_cache_entry() to create a new cache entry to replace the
higher-stage entries for the path that represents the conflict.

The make_cache_entry() function calls refresh_cache_entry() to fill
in the cached stat information.  To mark a cache entry as
up-to-date, the data is re-read from the file in the working tree,
and goes through convert_to_git() conversion to be compared with the
blob object name the new cache entry records.

It is important to note that this happens while the higher-stage
entries, which are going to be replaced with the new entry, are
still in the index.  Unfortunately, the convert_to_git() conversion
has a misguided "safer crlf" mechanism baked in, and looks at the
existing cache entry for the path to decide how to convert the
contents in the working tree file.  If our side (i.e. stage#2)
records a text blob with CRLF in it, even when the system is
configured to record LF in blobs and convert them to CRLF upon
checkout (and back to LF upon checkin), the "safer crlf" mechanism
stops us doing so.

This especially poses a problem during a renormalizing merge, where
the merge result for the path is computed by first "normalizing" the
blobs involved in the merge by using convert_to_working_tree()
followed by convert_to_git() with "safer crlf" disabled.  The merge
result that is computed correctly and fed to add_cacheinfo() via
update_file_flags() does _not_ match what refresh_cache_entry() sees
by converting the working tree file via convert_to_git().

We can work this around by not refreshing the new cache entry in
make_cache_entry() called by add_cacheinfo().  After add_cacheinfo()
adds the new entry, we can call refresh_cache_entry() on that,
knowing that addition of this new cache entry would have removed the
stale cache entries that had CRLF in stage #2 that were carried over
before the renormalizing merge started and will not interfere with
the correct recording of the result.

The test update was taken from a series by Torsten Bögershausen
that attempted to fix this with a different approach.

Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Reviewed-by: Torsten Bögershausen <tboegi@web.de>
1 parent 6523728
Raw File
string-list.h
#ifndef STRING_LIST_H
#define STRING_LIST_H

struct string_list_item {
	char *string;
	void *util;
};

typedef int (*compare_strings_fn)(const char *, const char *);

struct string_list {
	struct string_list_item *items;
	unsigned int nr, alloc;
	unsigned int strdup_strings:1;
	compare_strings_fn cmp; /* NULL uses strcmp() */
};

#define STRING_LIST_INIT_NODUP { NULL, 0, 0, 0, NULL }
#define STRING_LIST_INIT_DUP   { NULL, 0, 0, 1, NULL }

void string_list_init(struct string_list *list, int strdup_strings);

void print_string_list(const struct string_list *p, const char *text);
void string_list_clear(struct string_list *list, int free_util);

/* Use this function to call a custom clear function on each util pointer */
/* The string associated with the util pointer is passed as the second argument */
typedef void (*string_list_clear_func_t)(void *p, const char *str);
void string_list_clear_func(struct string_list *list, string_list_clear_func_t clearfunc);

/* Use this function or the macro below to iterate over each item */
typedef int (*string_list_each_func_t)(struct string_list_item *, void *);
int for_each_string_list(struct string_list *list,
			 string_list_each_func_t, void *cb_data);
#define for_each_string_list_item(item,list) \
	for (item = (list)->items; item < (list)->items + (list)->nr; ++item)

/*
 * Apply want to each item in list, retaining only the ones for which
 * the function returns true.  If free_util is true, call free() on
 * the util members of any items that have to be deleted.  Preserve
 * the order of the items that are retained.
 */
void filter_string_list(struct string_list *list, int free_util,
			string_list_each_func_t want, void *cb_data);

/*
 * Remove any empty strings from the list.  If free_util is true, call
 * free() on the util members of any items that have to be deleted.
 * Preserve the order of the items that are retained.
 */
void string_list_remove_empty_items(struct string_list *list, int free_util);

/* Use these functions only on sorted lists: */
int string_list_has_string(const struct string_list *list, const char *string);
int string_list_find_insert_index(const struct string_list *list, const char *string,
				  int negative_existing_index);
/*
 * Inserts the given string into the sorted list.
 * If the string already exists, the list is not altered.
 * Returns the string_list_item, the string is part of.
 */
struct string_list_item *string_list_insert(struct string_list *list, const char *string);

/*
 * Checks if the given string is part of a sorted list. If it is part of the list,
 * return the coresponding string_list_item, NULL otherwise.
 */
struct string_list_item *string_list_lookup(struct string_list *list, const char *string);

/*
 * Remove all but the first of consecutive entries with the same
 * string value.  If free_util is true, call free() on the util
 * members of any items that have to be deleted.
 */
void string_list_remove_duplicates(struct string_list *sorted_list, int free_util);


/* Use these functions only on unsorted lists: */

/*
 * Add string to the end of list.  If list->strdup_string is set, then
 * string is copied; otherwise the new string_list_entry refers to the
 * input string.
 */
struct string_list_item *string_list_append(struct string_list *list, const char *string);

/*
 * Like string_list_append(), except string is never copied.  When
 * list->strdup_strings is set, this function can be used to hand
 * ownership of a malloc()ed string to list without making an extra
 * copy.
 */
struct string_list_item *string_list_append_nodup(struct string_list *list, char *string);

void string_list_sort(struct string_list *list);
int unsorted_string_list_has_string(struct string_list *list, const char *string);
struct string_list_item *unsorted_string_list_lookup(struct string_list *list,
						     const char *string);

void unsorted_string_list_delete_item(struct string_list *list, int i, int free_util);

/*
 * Split string into substrings on character delim and append the
 * substrings to list.  The input string is not modified.
 * list->strdup_strings must be set, as new memory needs to be
 * allocated to hold the substrings.  If maxsplit is non-negative,
 * then split at most maxsplit times.  Return the number of substrings
 * appended to list.
 *
 * Examples:
 *   string_list_split(l, "foo:bar:baz", ':', -1) -> ["foo", "bar", "baz"]
 *   string_list_split(l, "foo:bar:baz", ':', 0) -> ["foo:bar:baz"]
 *   string_list_split(l, "foo:bar:baz", ':', 1) -> ["foo", "bar:baz"]
 *   string_list_split(l, "foo:bar:", ':', -1) -> ["foo", "bar", ""]
 *   string_list_split(l, "", ':', -1) -> [""]
 *   string_list_split(l, ":", ':', -1) -> ["", ""]
 */
int string_list_split(struct string_list *list, const char *string,
		      int delim, int maxsplit);

/*
 * Like string_list_split(), except that string is split in-place: the
 * delimiter characters in string are overwritten with NULs, and the
 * new string_list_items point into string (which therefore must not
 * be modified or freed while the string_list is in use).
 * list->strdup_strings must *not* be set.
 */
int string_list_split_in_place(struct string_list *list, char *string,
			       int delim, int maxsplit);
#endif /* STRING_LIST_H */
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