1045 lines
		
	
	
		
			23 KiB
		
	
	
	
		
			C
		
	
	
			
		
		
	
	
			1045 lines
		
	
	
		
			23 KiB
		
	
	
	
		
			C
		
	
	
| /*
 | |
|  * GIT - The information manager from hell
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|  *
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|  * Copyright (C) Linus Torvalds, 2005
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|  */
 | |
| #define DBRT_DEBUG 1
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| 
 | |
| #include "cache.h"
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| 
 | |
| #include "object.h"
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| #include "tree.h"
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| #include "tree-walk.h"
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| #include "cache-tree.h"
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| #include <sys/time.h>
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| #include <signal.h>
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| #include "builtin.h"
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| 
 | |
| static int reset = 0;
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| static int merge = 0;
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| static int update = 0;
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| static int index_only = 0;
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| static int nontrivial_merge = 0;
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| static int trivial_merges_only = 0;
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| static int aggressive = 0;
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| static int verbose_update = 0;
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| static volatile int progress_update = 0;
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| static const char *prefix = NULL;
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| 
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| static int head_idx = -1;
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| static int merge_size = 0;
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| 
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| static struct object_list *trees = NULL;
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| 
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| static struct cache_entry df_conflict_entry;
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| 
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| struct tree_entry_list {
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| 	struct tree_entry_list *next;
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| 	unsigned directory : 1;
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| 	unsigned executable : 1;
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| 	unsigned symlink : 1;
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| 	unsigned int mode;
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| 	const char *name;
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| 	const unsigned char *sha1;
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| };
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| 
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| static struct tree_entry_list df_conflict_list = {
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| 	.name = NULL,
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| 	.next = &df_conflict_list
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| };
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| 
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| typedef int (*merge_fn_t)(struct cache_entry **src);
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| 
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| static struct tree_entry_list *create_tree_entry_list(struct tree *tree)
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| {
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| 	struct tree_desc desc;
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| 	struct name_entry one;
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| 	struct tree_entry_list *ret = NULL;
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| 	struct tree_entry_list **list_p = &ret;
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| 
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| 	desc.buf = tree->buffer;
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| 	desc.size = tree->size;
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| 
 | |
| 	while (tree_entry(&desc, &one)) {
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| 		struct tree_entry_list *entry;
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| 
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| 		entry = xmalloc(sizeof(struct tree_entry_list));
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| 		entry->name = one.path;
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| 		entry->sha1 = one.sha1;
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| 		entry->mode = one.mode;
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| 		entry->directory = S_ISDIR(one.mode) != 0;
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| 		entry->executable = (one.mode & S_IXUSR) != 0;
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| 		entry->symlink = S_ISLNK(one.mode) != 0;
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| 		entry->next = NULL;
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| 
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| 		*list_p = entry;
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| 		list_p = &entry->next;
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| 	}
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| 	return ret;
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| }
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| 
 | |
| static int entcmp(const char *name1, int dir1, const char *name2, int dir2)
 | |
| {
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| 	int len1 = strlen(name1);
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| 	int len2 = strlen(name2);
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| 	int len = len1 < len2 ? len1 : len2;
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| 	int ret = memcmp(name1, name2, len);
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| 	unsigned char c1, c2;
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| 	if (ret)
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| 		return ret;
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| 	c1 = name1[len];
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| 	c2 = name2[len];
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| 	if (!c1 && dir1)
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| 		c1 = '/';
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| 	if (!c2 && dir2)
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| 		c2 = '/';
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| 	ret = (c1 < c2) ? -1 : (c1 > c2) ? 1 : 0;
 | |
| 	if (c1 && c2 && !ret)
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| 		ret = len1 - len2;
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| 	return ret;
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| }
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| 
 | |
| static int unpack_trees_rec(struct tree_entry_list **posns, int len,
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| 			    const char *base, merge_fn_t fn, int *indpos)
 | |
| {
 | |
| 	int baselen = strlen(base);
 | |
| 	int src_size = len + 1;
 | |
| 	do {
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| 		int i;
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| 		const char *first;
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| 		int firstdir = 0;
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| 		int pathlen;
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| 		unsigned ce_size;
 | |
| 		struct tree_entry_list **subposns;
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| 		struct cache_entry **src;
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| 		int any_files = 0;
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| 		int any_dirs = 0;
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| 		char *cache_name;
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| 		int ce_stage;
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| 
 | |
| 		/* Find the first name in the input. */
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| 
 | |
| 		first = NULL;
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| 		cache_name = NULL;
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| 
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| 		/* Check the cache */
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| 		if (merge && *indpos < active_nr) {
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| 			/* This is a bit tricky: */
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| 			/* If the index has a subdirectory (with
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| 			 * contents) as the first name, it'll get a
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| 			 * filename like "foo/bar". But that's after
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| 			 * "foo", so the entry in trees will get
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| 			 * handled first, at which point we'll go into
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| 			 * "foo", and deal with "bar" from the index,
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| 			 * because the base will be "foo/". The only
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| 			 * way we can actually have "foo/bar" first of
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| 			 * all the things is if the trees don't
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| 			 * contain "foo" at all, in which case we'll
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| 			 * handle "foo/bar" without going into the
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| 			 * directory, but that's fine (and will return
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| 			 * an error anyway, with the added unknown
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| 			 * file case.
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| 			 */
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| 
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| 			cache_name = active_cache[*indpos]->name;
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| 			if (strlen(cache_name) > baselen &&
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| 			    !memcmp(cache_name, base, baselen)) {
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| 				cache_name += baselen;
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| 				first = cache_name;
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| 			} else {
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| 				cache_name = NULL;
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| 			}
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| 		}
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| 
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| #if DBRT_DEBUG > 1
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| 		if (first)
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| 			printf("index %s\n", first);
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| #endif
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| 		for (i = 0; i < len; i++) {
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| 			if (!posns[i] || posns[i] == &df_conflict_list)
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| 				continue;
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| #if DBRT_DEBUG > 1
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| 			printf("%d %s\n", i + 1, posns[i]->name);
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| #endif
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| 			if (!first || entcmp(first, firstdir,
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| 					     posns[i]->name, 
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| 					     posns[i]->directory) > 0) {
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| 				first = posns[i]->name;
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| 				firstdir = posns[i]->directory;
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| 			}
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| 		}
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| 		/* No name means we're done */
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| 		if (!first)
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| 			return 0;
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| 
 | |
| 		pathlen = strlen(first);
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| 		ce_size = cache_entry_size(baselen + pathlen);
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| 
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| 		src = xcalloc(src_size, sizeof(struct cache_entry *));
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| 
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| 		subposns = xcalloc(len, sizeof(struct tree_list_entry *));
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| 
 | |
| 		if (cache_name && !strcmp(cache_name, first)) {
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| 			any_files = 1;
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| 			src[0] = active_cache[*indpos];
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| 			remove_cache_entry_at(*indpos);
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| 		}
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| 
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| 		for (i = 0; i < len; i++) {
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| 			struct cache_entry *ce;
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| 
 | |
| 			if (!posns[i] ||
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| 			    (posns[i] != &df_conflict_list &&
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| 			     strcmp(first, posns[i]->name))) {
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| 				continue;
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| 			}
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| 
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| 			if (posns[i] == &df_conflict_list) {
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| 				src[i + merge] = &df_conflict_entry;
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| 				continue;
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| 			}
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| 
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| 			if (posns[i]->directory) {
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| 				struct tree *tree = lookup_tree(posns[i]->sha1);
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| 				any_dirs = 1;
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| 				parse_tree(tree);
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| 				subposns[i] = create_tree_entry_list(tree);
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| 				posns[i] = posns[i]->next;
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| 				src[i + merge] = &df_conflict_entry;
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| 				continue;
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| 			}
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| 
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| 			if (!merge)
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| 				ce_stage = 0;
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| 			else if (i + 1 < head_idx)
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| 				ce_stage = 1;
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| 			else if (i + 1 > head_idx)
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| 				ce_stage = 3;
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| 			else
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| 				ce_stage = 2;
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| 
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| 			ce = xcalloc(1, ce_size);
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| 			ce->ce_mode = create_ce_mode(posns[i]->mode);
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| 			ce->ce_flags = create_ce_flags(baselen + pathlen,
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| 						       ce_stage);
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| 			memcpy(ce->name, base, baselen);
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| 			memcpy(ce->name + baselen, first, pathlen + 1);
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| 
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| 			any_files = 1;
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| 
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| 			memcpy(ce->sha1, posns[i]->sha1, 20);
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| 			src[i + merge] = ce;
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| 			subposns[i] = &df_conflict_list;
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| 			posns[i] = posns[i]->next;
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| 		}
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| 		if (any_files) {
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| 			if (merge) {
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| 				int ret;
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| 
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| #if DBRT_DEBUG > 1
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| 				printf("%s:\n", first);
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| 				for (i = 0; i < src_size; i++) {
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| 					printf(" %d ", i);
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| 					if (src[i])
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| 						printf("%s\n", sha1_to_hex(src[i]->sha1));
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| 					else
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| 						printf("\n");
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| 				}
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| #endif
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| 				ret = fn(src);
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| 				
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| #if DBRT_DEBUG > 1
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| 				printf("Added %d entries\n", ret);
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| #endif
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| 				*indpos += ret;
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| 			} else {
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| 				for (i = 0; i < src_size; i++) {
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| 					if (src[i]) {
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| 						add_cache_entry(src[i], ADD_CACHE_OK_TO_ADD|ADD_CACHE_SKIP_DFCHECK);
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| 					}
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| 				}
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| 			}
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| 		}
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| 		if (any_dirs) {
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| 			char *newbase = xmalloc(baselen + 2 + pathlen);
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| 			memcpy(newbase, base, baselen);
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| 			memcpy(newbase + baselen, first, pathlen);
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| 			newbase[baselen + pathlen] = '/';
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| 			newbase[baselen + pathlen + 1] = '\0';
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| 			if (unpack_trees_rec(subposns, len, newbase, fn,
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| 					     indpos))
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| 				return -1;
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| 			free(newbase);
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| 		}
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| 		free(subposns);
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| 		free(src);
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| 	} while (1);
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| }
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| 
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| static void reject_merge(struct cache_entry *ce)
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| {
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| 	die("Entry '%s' would be overwritten by merge. Cannot merge.", 
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| 	    ce->name);
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| }
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| 
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| /* Unlink the last component and attempt to remove leading
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|  * directories, in case this unlink is the removal of the
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|  * last entry in the directory -- empty directories are removed.
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|  */
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| static void unlink_entry(char *name)
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| {
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| 	char *cp, *prev;
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| 
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| 	if (unlink(name))
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| 		return;
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| 	prev = NULL;
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| 	while (1) {
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| 		int status;
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| 		cp = strrchr(name, '/');
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| 		if (prev)
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| 			*prev = '/';
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| 		if (!cp)
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| 			break;
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| 
 | |
| 		*cp = 0;
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| 		status = rmdir(name);
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| 		if (status) {
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| 			*cp = '/';
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| 			break;
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| 		}
 | |
| 		prev = cp;
 | |
| 	}
 | |
| }
 | |
| 
 | |
| static void progress_interval(int signum)
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| {
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| 	progress_update = 1;
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| }
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| 
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| static void setup_progress_signal(void)
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| {
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| 	struct sigaction sa;
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| 	struct itimerval v;
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| 
 | |
| 	memset(&sa, 0, sizeof(sa));
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| 	sa.sa_handler = progress_interval;
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| 	sigemptyset(&sa.sa_mask);
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| 	sa.sa_flags = SA_RESTART;
 | |
| 	sigaction(SIGALRM, &sa, NULL);
 | |
| 
 | |
| 	v.it_interval.tv_sec = 1;
 | |
| 	v.it_interval.tv_usec = 0;
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| 	v.it_value = v.it_interval;
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| 	setitimer(ITIMER_REAL, &v, NULL);
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| }
 | |
| 
 | |
| static void check_updates(struct cache_entry **src, int nr)
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| {
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| 	static struct checkout state = {
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| 		.base_dir = "",
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| 		.force = 1,
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| 		.quiet = 1,
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| 		.refresh_cache = 1,
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| 	};
 | |
| 	unsigned short mask = htons(CE_UPDATE);
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| 	unsigned last_percent = 200, cnt = 0, total = 0;
 | |
| 
 | |
| 	if (update && verbose_update) {
 | |
| 		for (total = cnt = 0; cnt < nr; cnt++) {
 | |
| 			struct cache_entry *ce = src[cnt];
 | |
| 			if (!ce->ce_mode || ce->ce_flags & mask)
 | |
| 				total++;
 | |
| 		}
 | |
| 
 | |
| 		/* Don't bother doing this for very small updates */
 | |
| 		if (total < 250)
 | |
| 			total = 0;
 | |
| 
 | |
| 		if (total) {
 | |
| 			fprintf(stderr, "Checking files out...\n");
 | |
| 			setup_progress_signal();
 | |
| 			progress_update = 1;
 | |
| 		}
 | |
| 		cnt = 0;
 | |
| 	}
 | |
| 
 | |
| 	while (nr--) {
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| 		struct cache_entry *ce = *src++;
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| 
 | |
| 		if (total) {
 | |
| 			if (!ce->ce_mode || ce->ce_flags & mask) {
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| 				unsigned percent;
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| 				cnt++;
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| 				percent = (cnt * 100) / total;
 | |
| 				if (percent != last_percent ||
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| 				    progress_update) {
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| 					fprintf(stderr, "%4u%% (%u/%u) done\r",
 | |
| 						percent, cnt, total);
 | |
| 					last_percent = percent;
 | |
| 					progress_update = 0;
 | |
| 				}
 | |
| 			}
 | |
| 		}
 | |
| 		if (!ce->ce_mode) {
 | |
| 			if (update)
 | |
| 				unlink_entry(ce->name);
 | |
| 			continue;
 | |
| 		}
 | |
| 		if (ce->ce_flags & mask) {
 | |
| 			ce->ce_flags &= ~mask;
 | |
| 			if (update)
 | |
| 				checkout_entry(ce, &state, NULL);
 | |
| 		}
 | |
| 	}
 | |
| 	if (total) {
 | |
| 		signal(SIGALRM, SIG_IGN);
 | |
| 		fputc('\n', stderr);
 | |
| 	}
 | |
| }
 | |
| 
 | |
| static int unpack_trees(merge_fn_t fn)
 | |
| {
 | |
| 	int indpos = 0;
 | |
| 	unsigned len = object_list_length(trees);
 | |
| 	struct tree_entry_list **posns;
 | |
| 	int i;
 | |
| 	struct object_list *posn = trees;
 | |
| 	merge_size = len;
 | |
| 
 | |
| 	if (len) {
 | |
| 		posns = xmalloc(len * sizeof(struct tree_entry_list *));
 | |
| 		for (i = 0; i < len; i++) {
 | |
| 			posns[i] = create_tree_entry_list((struct tree *) posn->item);
 | |
| 			posn = posn->next;
 | |
| 		}
 | |
| 		if (unpack_trees_rec(posns, len, prefix ? prefix : "",
 | |
| 				     fn, &indpos))
 | |
| 			return -1;
 | |
| 	}
 | |
| 
 | |
| 	if (trivial_merges_only && nontrivial_merge)
 | |
| 		die("Merge requires file-level merging");
 | |
| 
 | |
| 	check_updates(active_cache, active_nr);
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int list_tree(unsigned char *sha1)
 | |
| {
 | |
| 	struct tree *tree = parse_tree_indirect(sha1);
 | |
| 	if (!tree)
 | |
| 		return -1;
 | |
| 	object_list_append(&tree->object, &trees);
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int same(struct cache_entry *a, struct cache_entry *b)
 | |
| {
 | |
| 	if (!!a != !!b)
 | |
| 		return 0;
 | |
| 	if (!a && !b)
 | |
| 		return 1;
 | |
| 	return a->ce_mode == b->ce_mode && 
 | |
| 		!memcmp(a->sha1, b->sha1, 20);
 | |
| }
 | |
| 
 | |
| 
 | |
| /*
 | |
|  * When a CE gets turned into an unmerged entry, we
 | |
|  * want it to be up-to-date
 | |
|  */
 | |
| static void verify_uptodate(struct cache_entry *ce)
 | |
| {
 | |
| 	struct stat st;
 | |
| 
 | |
| 	if (index_only || reset)
 | |
| 		return;
 | |
| 
 | |
| 	if (!lstat(ce->name, &st)) {
 | |
| 		unsigned changed = ce_match_stat(ce, &st, 1);
 | |
| 		if (!changed)
 | |
| 			return;
 | |
| 		errno = 0;
 | |
| 	}
 | |
| 	if (reset) {
 | |
| 		ce->ce_flags |= htons(CE_UPDATE);
 | |
| 		return;
 | |
| 	}
 | |
| 	if (errno == ENOENT)
 | |
| 		return;
 | |
| 	die("Entry '%s' not uptodate. Cannot merge.", ce->name);
 | |
| }
 | |
| 
 | |
| static void invalidate_ce_path(struct cache_entry *ce)
 | |
| {
 | |
| 	if (ce)
 | |
| 		cache_tree_invalidate_path(active_cache_tree, ce->name);
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * We do not want to remove or overwrite a working tree file that
 | |
|  * is not tracked.
 | |
|  */
 | |
| static void verify_absent(const char *path, const char *action)
 | |
| {
 | |
| 	struct stat st;
 | |
| 
 | |
| 	if (index_only || reset || !update)
 | |
| 		return;
 | |
| 	if (!lstat(path, &st))
 | |
| 		die("Untracked working tree file '%s' "
 | |
| 		    "would be %s by merge.", path, action);
 | |
| }
 | |
| 
 | |
| static int merged_entry(struct cache_entry *merge, struct cache_entry *old)
 | |
| {
 | |
| 	merge->ce_flags |= htons(CE_UPDATE);
 | |
| 	if (old) {
 | |
| 		/*
 | |
| 		 * See if we can re-use the old CE directly?
 | |
| 		 * That way we get the uptodate stat info.
 | |
| 		 *
 | |
| 		 * This also removes the UPDATE flag on
 | |
| 		 * a match.
 | |
| 		 */
 | |
| 		if (same(old, merge)) {
 | |
| 			*merge = *old;
 | |
| 		} else {
 | |
| 			verify_uptodate(old);
 | |
| 			invalidate_ce_path(old);
 | |
| 		}
 | |
| 	}
 | |
| 	else {
 | |
| 		verify_absent(merge->name, "overwritten");
 | |
| 		invalidate_ce_path(merge);
 | |
| 	}
 | |
| 
 | |
| 	merge->ce_flags &= ~htons(CE_STAGEMASK);
 | |
| 	add_cache_entry(merge, ADD_CACHE_OK_TO_ADD);
 | |
| 	return 1;
 | |
| }
 | |
| 
 | |
| static int deleted_entry(struct cache_entry *ce, struct cache_entry *old)
 | |
| {
 | |
| 	if (old)
 | |
| 		verify_uptodate(old);
 | |
| 	else
 | |
| 		verify_absent(ce->name, "removed");
 | |
| 	ce->ce_mode = 0;
 | |
| 	add_cache_entry(ce, ADD_CACHE_OK_TO_ADD);
 | |
| 	invalidate_ce_path(ce);
 | |
| 	return 1;
 | |
| }
 | |
| 
 | |
| static int keep_entry(struct cache_entry *ce)
 | |
| {
 | |
| 	add_cache_entry(ce, ADD_CACHE_OK_TO_ADD);
 | |
| 	return 1;
 | |
| }
 | |
| 
 | |
| #if DBRT_DEBUG
 | |
| static void show_stage_entry(FILE *o,
 | |
| 			     const char *label, const struct cache_entry *ce)
 | |
| {
 | |
| 	if (!ce)
 | |
| 		fprintf(o, "%s (missing)\n", label);
 | |
| 	else
 | |
| 		fprintf(o, "%s%06o %s %d\t%s\n",
 | |
| 			label,
 | |
| 			ntohl(ce->ce_mode),
 | |
| 			sha1_to_hex(ce->sha1),
 | |
| 			ce_stage(ce),
 | |
| 			ce->name);
 | |
| }
 | |
| #endif
 | |
| 
 | |
| static int threeway_merge(struct cache_entry **stages)
 | |
| {
 | |
| 	struct cache_entry *index;
 | |
| 	struct cache_entry *head; 
 | |
| 	struct cache_entry *remote = stages[head_idx + 1];
 | |
| 	int count;
 | |
| 	int head_match = 0;
 | |
| 	int remote_match = 0;
 | |
| 	const char *path = NULL;
 | |
| 
 | |
| 	int df_conflict_head = 0;
 | |
| 	int df_conflict_remote = 0;
 | |
| 
 | |
| 	int any_anc_missing = 0;
 | |
| 	int no_anc_exists = 1;
 | |
| 	int i;
 | |
| 
 | |
| 	for (i = 1; i < head_idx; i++) {
 | |
| 		if (!stages[i])
 | |
| 			any_anc_missing = 1;
 | |
| 		else {
 | |
| 			if (!path)
 | |
| 				path = stages[i]->name;
 | |
| 			no_anc_exists = 0;
 | |
| 		}
 | |
| 	}
 | |
| 
 | |
| 	index = stages[0];
 | |
| 	head = stages[head_idx];
 | |
| 
 | |
| 	if (head == &df_conflict_entry) {
 | |
| 		df_conflict_head = 1;
 | |
| 		head = NULL;
 | |
| 	}
 | |
| 
 | |
| 	if (remote == &df_conflict_entry) {
 | |
| 		df_conflict_remote = 1;
 | |
| 		remote = NULL;
 | |
| 	}
 | |
| 
 | |
| 	if (!path && index)
 | |
| 		path = index->name;
 | |
| 	if (!path && head)
 | |
| 		path = head->name;
 | |
| 	if (!path && remote)
 | |
| 		path = remote->name;
 | |
| 
 | |
| 	/* First, if there's a #16 situation, note that to prevent #13
 | |
| 	 * and #14.
 | |
| 	 */
 | |
| 	if (!same(remote, head)) {
 | |
| 		for (i = 1; i < head_idx; i++) {
 | |
| 			if (same(stages[i], head)) {
 | |
| 				head_match = i;
 | |
| 			}
 | |
| 			if (same(stages[i], remote)) {
 | |
| 				remote_match = i;
 | |
| 			}
 | |
| 		}
 | |
| 	}
 | |
| 
 | |
| 	/* We start with cases where the index is allowed to match
 | |
| 	 * something other than the head: #14(ALT) and #2ALT, where it
 | |
| 	 * is permitted to match the result instead.
 | |
| 	 */
 | |
| 	/* #14, #14ALT, #2ALT */
 | |
| 	if (remote && !df_conflict_head && head_match && !remote_match) {
 | |
| 		if (index && !same(index, remote) && !same(index, head))
 | |
| 			reject_merge(index);
 | |
| 		return merged_entry(remote, index);
 | |
| 	}
 | |
| 	/*
 | |
| 	 * If we have an entry in the index cache, then we want to
 | |
| 	 * make sure that it matches head.
 | |
| 	 */
 | |
| 	if (index && !same(index, head)) {
 | |
| 		reject_merge(index);
 | |
| 	}
 | |
| 
 | |
| 	if (head) {
 | |
| 		/* #5ALT, #15 */
 | |
| 		if (same(head, remote))
 | |
| 			return merged_entry(head, index);
 | |
| 		/* #13, #3ALT */
 | |
| 		if (!df_conflict_remote && remote_match && !head_match)
 | |
| 			return merged_entry(head, index);
 | |
| 	}
 | |
| 
 | |
| 	/* #1 */
 | |
| 	if (!head && !remote && any_anc_missing)
 | |
| 		return 0;
 | |
| 
 | |
| 	/* Under the new "aggressive" rule, we resolve mostly trivial
 | |
| 	 * cases that we historically had git-merge-one-file resolve.
 | |
| 	 */
 | |
| 	if (aggressive) {
 | |
| 		int head_deleted = !head && !df_conflict_head;
 | |
| 		int remote_deleted = !remote && !df_conflict_remote;
 | |
| 		/*
 | |
| 		 * Deleted in both.
 | |
| 		 * Deleted in one and unchanged in the other.
 | |
| 		 */
 | |
| 		if ((head_deleted && remote_deleted) ||
 | |
| 		    (head_deleted && remote && remote_match) ||
 | |
| 		    (remote_deleted && head && head_match)) {
 | |
| 			if (index)
 | |
| 				return deleted_entry(index, index);
 | |
| 			else if (path)
 | |
| 				verify_absent(path, "removed");
 | |
| 			return 0;
 | |
| 		}
 | |
| 		/*
 | |
| 		 * Added in both, identically.
 | |
| 		 */
 | |
| 		if (no_anc_exists && head && remote && same(head, remote))
 | |
| 			return merged_entry(head, index);
 | |
| 
 | |
| 	}
 | |
| 
 | |
| 	/* Below are "no merge" cases, which require that the index be
 | |
| 	 * up-to-date to avoid the files getting overwritten with
 | |
| 	 * conflict resolution files. 
 | |
| 	 */
 | |
| 	if (index) {
 | |
| 		verify_uptodate(index);
 | |
| 	}
 | |
| 	else if (path)
 | |
| 		verify_absent(path, "overwritten");
 | |
| 
 | |
| 	nontrivial_merge = 1;
 | |
| 
 | |
| 	/* #2, #3, #4, #6, #7, #9, #11. */
 | |
| 	count = 0;
 | |
| 	if (!head_match || !remote_match) {
 | |
| 		for (i = 1; i < head_idx; i++) {
 | |
| 			if (stages[i]) {
 | |
| 				keep_entry(stages[i]);
 | |
| 				count++;
 | |
| 				break;
 | |
| 			}
 | |
| 		}
 | |
| 	}
 | |
| #if DBRT_DEBUG
 | |
| 	else {
 | |
| 		fprintf(stderr, "read-tree: warning #16 detected\n");
 | |
| 		show_stage_entry(stderr, "head   ", stages[head_match]);
 | |
| 		show_stage_entry(stderr, "remote ", stages[remote_match]);
 | |
| 	}
 | |
| #endif
 | |
| 	if (head) { count += keep_entry(head); }
 | |
| 	if (remote) { count += keep_entry(remote); }
 | |
| 	return count;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Two-way merge.
 | |
|  *
 | |
|  * The rule is to "carry forward" what is in the index without losing
 | |
|  * information across a "fast forward", favoring a successful merge
 | |
|  * over a merge failure when it makes sense.  For details of the
 | |
|  * "carry forward" rule, please see <Documentation/git-read-tree.txt>.
 | |
|  *
 | |
|  */
 | |
| static int twoway_merge(struct cache_entry **src)
 | |
| {
 | |
| 	struct cache_entry *current = src[0];
 | |
| 	struct cache_entry *oldtree = src[1], *newtree = src[2];
 | |
| 
 | |
| 	if (merge_size != 2)
 | |
| 		return error("Cannot do a twoway merge of %d trees",
 | |
| 			     merge_size);
 | |
| 
 | |
| 	if (current) {
 | |
| 		if ((!oldtree && !newtree) || /* 4 and 5 */
 | |
| 		    (!oldtree && newtree &&
 | |
| 		     same(current, newtree)) || /* 6 and 7 */
 | |
| 		    (oldtree && newtree &&
 | |
| 		     same(oldtree, newtree)) || /* 14 and 15 */
 | |
| 		    (oldtree && newtree &&
 | |
| 		     !same(oldtree, newtree) && /* 18 and 19*/
 | |
| 		     same(current, newtree))) {
 | |
| 			return keep_entry(current);
 | |
| 		}
 | |
| 		else if (oldtree && !newtree && same(current, oldtree)) {
 | |
| 			/* 10 or 11 */
 | |
| 			return deleted_entry(oldtree, current);
 | |
| 		}
 | |
| 		else if (oldtree && newtree &&
 | |
| 			 same(current, oldtree) && !same(current, newtree)) {
 | |
| 			/* 20 or 21 */
 | |
| 			return merged_entry(newtree, current);
 | |
| 		}
 | |
| 		else {
 | |
| 			/* all other failures */
 | |
| 			if (oldtree)
 | |
| 				reject_merge(oldtree);
 | |
| 			if (current)
 | |
| 				reject_merge(current);
 | |
| 			if (newtree)
 | |
| 				reject_merge(newtree);
 | |
| 			return -1;
 | |
| 		}
 | |
| 	}
 | |
| 	else if (newtree)
 | |
| 		return merged_entry(newtree, current);
 | |
| 	else
 | |
| 		return deleted_entry(oldtree, current);
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Bind merge.
 | |
|  *
 | |
|  * Keep the index entries at stage0, collapse stage1 but make sure
 | |
|  * stage0 does not have anything there.
 | |
|  */
 | |
| static int bind_merge(struct cache_entry **src)
 | |
| {
 | |
| 	struct cache_entry *old = src[0];
 | |
| 	struct cache_entry *a = src[1];
 | |
| 
 | |
| 	if (merge_size != 1)
 | |
| 		return error("Cannot do a bind merge of %d trees\n",
 | |
| 			     merge_size);
 | |
| 	if (a && old)
 | |
| 		die("Entry '%s' overlaps.  Cannot bind.", a->name);
 | |
| 	if (!a)
 | |
| 		return keep_entry(old);
 | |
| 	else
 | |
| 		return merged_entry(a, NULL);
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * One-way merge.
 | |
|  *
 | |
|  * The rule is:
 | |
|  * - take the stat information from stage0, take the data from stage1
 | |
|  */
 | |
| static int oneway_merge(struct cache_entry **src)
 | |
| {
 | |
| 	struct cache_entry *old = src[0];
 | |
| 	struct cache_entry *a = src[1];
 | |
| 
 | |
| 	if (merge_size != 1)
 | |
| 		return error("Cannot do a oneway merge of %d trees",
 | |
| 			     merge_size);
 | |
| 
 | |
| 	if (!a)
 | |
| 		return deleted_entry(old, old);
 | |
| 	if (old && same(old, a)) {
 | |
| 		if (reset) {
 | |
| 			struct stat st;
 | |
| 			if (lstat(old->name, &st) ||
 | |
| 			    ce_match_stat(old, &st, 1))
 | |
| 				old->ce_flags |= htons(CE_UPDATE);
 | |
| 		}
 | |
| 		return keep_entry(old);
 | |
| 	}
 | |
| 	return merged_entry(a, old);
 | |
| }
 | |
| 
 | |
| static int read_cache_unmerged(void)
 | |
| {
 | |
| 	int i;
 | |
| 	struct cache_entry **dst;
 | |
| 	struct cache_entry *last = NULL;
 | |
| 
 | |
| 	read_cache();
 | |
| 	dst = active_cache;
 | |
| 	for (i = 0; i < active_nr; i++) {
 | |
| 		struct cache_entry *ce = active_cache[i];
 | |
| 		if (ce_stage(ce)) {
 | |
| 			if (last && !strcmp(ce->name, last->name))
 | |
| 				continue;
 | |
| 			invalidate_ce_path(ce);
 | |
| 			last = ce;
 | |
| 			ce->ce_mode = 0;
 | |
| 			ce->ce_flags &= ~htons(CE_STAGEMASK);
 | |
| 		}
 | |
| 		*dst++ = ce;
 | |
| 	}
 | |
| 	active_nr = dst - active_cache;
 | |
| 	return !!last;
 | |
| }
 | |
| 
 | |
| static void prime_cache_tree_rec(struct cache_tree *it, struct tree *tree)
 | |
| {
 | |
| 	struct tree_desc desc;
 | |
| 	struct name_entry entry;
 | |
| 	int cnt;
 | |
| 
 | |
| 	memcpy(it->sha1, tree->object.sha1, 20);
 | |
| 	desc.buf = tree->buffer;
 | |
| 	desc.size = tree->size;
 | |
| 	cnt = 0;
 | |
| 	while (tree_entry(&desc, &entry)) {
 | |
| 		if (!S_ISDIR(entry.mode))
 | |
| 			cnt++;
 | |
| 		else {
 | |
| 			struct cache_tree_sub *sub;
 | |
| 			struct tree *subtree = lookup_tree(entry.sha1);
 | |
| 			if (!subtree->object.parsed)
 | |
| 				parse_tree(subtree);
 | |
| 			sub = cache_tree_sub(it, entry.path);
 | |
| 			sub->cache_tree = cache_tree();
 | |
| 			prime_cache_tree_rec(sub->cache_tree, subtree);
 | |
| 			cnt += sub->cache_tree->entry_count;
 | |
| 		}
 | |
| 	}
 | |
| 	it->entry_count = cnt;
 | |
| }
 | |
| 
 | |
| static void prime_cache_tree(void)
 | |
| {
 | |
| 	struct tree *tree = (struct tree *)trees->item;
 | |
| 	if (!tree)
 | |
| 		return;
 | |
| 	active_cache_tree = cache_tree();
 | |
| 	prime_cache_tree_rec(active_cache_tree, tree);
 | |
| 
 | |
| }
 | |
| 
 | |
| static const char read_tree_usage[] = "git-read-tree (<sha> | [[-m [--aggressive] | --reset | --prefix=<prefix>] [-u | -i]] <sha1> [<sha2> [<sha3>]])";
 | |
| 
 | |
| static struct lock_file lock_file;
 | |
| 
 | |
| int cmd_read_tree(int argc, const char **argv, char **envp)
 | |
| {
 | |
| 	int i, newfd, stage = 0;
 | |
| 	unsigned char sha1[20];
 | |
| 	merge_fn_t fn = NULL;
 | |
| 
 | |
| 	setup_git_directory();
 | |
| 	git_config(git_default_config);
 | |
| 
 | |
| 	newfd = hold_lock_file_for_update(&lock_file, get_index_file());
 | |
| 	if (newfd < 0)
 | |
| 		die("unable to create new index file");
 | |
| 
 | |
| 	git_config(git_default_config);
 | |
| 
 | |
| 	merge = 0;
 | |
| 	reset = 0;
 | |
| 	for (i = 1; i < argc; i++) {
 | |
| 		const char *arg = argv[i];
 | |
| 
 | |
| 		/* "-u" means "update", meaning that a merge will update
 | |
| 		 * the working tree.
 | |
| 		 */
 | |
| 		if (!strcmp(arg, "-u")) {
 | |
| 			update = 1;
 | |
| 			continue;
 | |
| 		}
 | |
| 
 | |
| 		if (!strcmp(arg, "-v")) {
 | |
| 			verbose_update = 1;
 | |
| 			continue;
 | |
| 		}
 | |
| 
 | |
| 		/* "-i" means "index only", meaning that a merge will
 | |
| 		 * not even look at the working tree.
 | |
| 		 */
 | |
| 		if (!strcmp(arg, "-i")) {
 | |
| 			index_only = 1;
 | |
| 			continue;
 | |
| 		}
 | |
| 
 | |
| 		/* "--prefix=<subdirectory>/" means keep the current index
 | |
| 		 *  entries and put the entries from the tree under the
 | |
| 		 * given subdirectory.
 | |
| 		 */
 | |
| 		if (!strncmp(arg, "--prefix=", 9)) {
 | |
| 			if (stage || merge || prefix)
 | |
| 				usage(read_tree_usage);
 | |
| 			prefix = arg + 9;
 | |
| 			merge = 1;
 | |
| 			stage = 1;
 | |
| 			if (read_cache_unmerged())
 | |
| 				die("you need to resolve your current index first");
 | |
| 			continue;
 | |
| 		}
 | |
| 
 | |
| 		/* This differs from "-m" in that we'll silently ignore
 | |
| 		 * unmerged entries and overwrite working tree files that
 | |
| 		 * correspond to them.
 | |
| 		 */
 | |
| 		if (!strcmp(arg, "--reset")) {
 | |
| 			if (stage || merge || prefix)
 | |
| 				usage(read_tree_usage);
 | |
| 			reset = 1;
 | |
| 			merge = 1;
 | |
| 			stage = 1;
 | |
| 			read_cache_unmerged();
 | |
| 			continue;
 | |
| 		}
 | |
| 
 | |
| 		if (!strcmp(arg, "--trivial")) {
 | |
| 			trivial_merges_only = 1;
 | |
| 			continue;
 | |
| 		}
 | |
| 
 | |
| 		if (!strcmp(arg, "--aggressive")) {
 | |
| 			aggressive = 1;
 | |
| 			continue;
 | |
| 		}
 | |
| 
 | |
| 		/* "-m" stands for "merge", meaning we start in stage 1 */
 | |
| 		if (!strcmp(arg, "-m")) {
 | |
| 			if (stage || merge || prefix)
 | |
| 				usage(read_tree_usage);
 | |
| 			if (read_cache_unmerged())
 | |
| 				die("you need to resolve your current index first");
 | |
| 			stage = 1;
 | |
| 			merge = 1;
 | |
| 			continue;
 | |
| 		}
 | |
| 
 | |
| 		/* using -u and -i at the same time makes no sense */
 | |
| 		if (1 < index_only + update)
 | |
| 			usage(read_tree_usage);
 | |
| 
 | |
| 		if (get_sha1(arg, sha1))
 | |
| 			die("Not a valid object name %s", arg);
 | |
| 		if (list_tree(sha1) < 0)
 | |
| 			die("failed to unpack tree object %s", arg);
 | |
| 		stage++;
 | |
| 	}
 | |
| 	if ((update||index_only) && !merge)
 | |
| 		usage(read_tree_usage);
 | |
| 
 | |
| 	if (prefix) {
 | |
| 		int pfxlen = strlen(prefix);
 | |
| 		int pos;
 | |
| 		if (prefix[pfxlen-1] != '/')
 | |
| 			die("prefix must end with /");
 | |
| 		if (stage != 2)
 | |
| 			die("binding merge takes only one tree");
 | |
| 		pos = cache_name_pos(prefix, pfxlen);
 | |
| 		if (0 <= pos)
 | |
| 			die("corrupt index file");
 | |
| 		pos = -pos-1;
 | |
| 		if (pos < active_nr &&
 | |
| 		    !strncmp(active_cache[pos]->name, prefix, pfxlen))
 | |
| 			die("subdirectory '%s' already exists.", prefix);
 | |
| 		pos = cache_name_pos(prefix, pfxlen-1);
 | |
| 		if (0 <= pos)
 | |
| 			die("file '%.*s' already exists.", pfxlen-1, prefix);
 | |
| 	}
 | |
| 
 | |
| 	if (merge) {
 | |
| 		if (stage < 2)
 | |
| 			die("just how do you expect me to merge %d trees?", stage-1);
 | |
| 		switch (stage - 1) {
 | |
| 		case 1:
 | |
| 			fn = prefix ? bind_merge : oneway_merge;
 | |
| 			break;
 | |
| 		case 2:
 | |
| 			fn = twoway_merge;
 | |
| 			break;
 | |
| 		case 3:
 | |
| 		default:
 | |
| 			fn = threeway_merge;
 | |
| 			cache_tree_free(&active_cache_tree);
 | |
| 			break;
 | |
| 		}
 | |
| 
 | |
| 		if (stage - 1 >= 3)
 | |
| 			head_idx = stage - 2;
 | |
| 		else
 | |
| 			head_idx = 1;
 | |
| 	}
 | |
| 
 | |
| 	unpack_trees(fn);
 | |
| 
 | |
| 	/*
 | |
| 	 * When reading only one tree (either the most basic form,
 | |
| 	 * "-m ent" or "--reset ent" form), we can obtain a fully
 | |
| 	 * valid cache-tree because the index must match exactly
 | |
| 	 * what came from the tree.
 | |
| 	 */
 | |
| 	if (trees && trees->item && !prefix && (!merge || (stage == 2))) {
 | |
| 		cache_tree_free(&active_cache_tree);
 | |
| 		prime_cache_tree();
 | |
| 	}
 | |
| 
 | |
| 	if (write_cache(newfd, active_cache, active_nr) ||
 | |
| 	    commit_lock_file(&lock_file))
 | |
| 		die("unable to write new index file");
 | |
| 	return 0;
 | |
| }
 |