X-Git-Url: https://git.verplant.org/?a=blobdiff_plain;f=read-cache.c;h=2ee96bc92c37a204a844afb3354483b733db0c4e;hb=5c2a7fbc362e4227ced84c32c3fdc9682d085962;hp=53da50065d75019d35610f480d9708247f4e0cf6;hpb=73134b6d3f700bb9e6c66aa2f099de644c6b8d09;p=git.git

diff --git a/read-cache.c b/read-cache.c
index 53da5006..2ee96bc9 100644
--- a/read-cache.c
+++ b/read-cache.c
@@ -12,10 +12,12 @@ unsigned int active_nr = 0, active_alloc = 0;
 void usage(const char *err, ...)
 {
 	va_list args;
+	char string[200];
 
 	va_start(args, err);
-	vfprintf(stderr, err, args);
+	vsnprintf(string, sizeof(string), err, args);
 	va_end(args);
+	fprintf(stderr, "%s\n", string);
 	exit(1);
 }
 
@@ -214,8 +216,25 @@ int write_sha1_buffer(const unsigned char *sha1, void *buf, unsigned int size)
 	int fd;
 
 	fd = open(filename, O_WRONLY | O_CREAT | O_EXCL, 0666);
-	if (fd < 0)
-		return (errno == EEXIST) ? 0 : -1;
+	if (fd < 0) {
+		void *map;
+		static int error(const char * string);
+
+		if (errno != EEXIST)
+			return -1;
+#ifndef COLLISION_CHECK
+		fd = open(filename, O_RDONLY);
+		if (fd < 0)
+			return -1;
+		map = mmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
+		if (map == MAP_FAILED)
+			return -1;
+		if (memcmp(buf, map, size))
+			return error("SHA1 collision detected!"
+					" This is bad, bad, BAD!\a\n");
+#endif
+		return 0;
+	}
 	write(fd, buf, size);
 	close(fd);
 	return 0;
@@ -276,24 +295,23 @@ int cache_name_pos(const char *name, int namelen)
 		struct cache_entry *ce = active_cache[next];
 		int cmp = cache_name_compare(name, namelen, ce->name, ce->namelen);
 		if (!cmp)
-			return -next-1;
+			return next;
 		if (cmp < 0) {
 			last = next;
 			continue;
 		}
 		first = next+1;
 	}
-	return first;
+	return -first-1;
 }
 
 int remove_file_from_cache(char *path)
 {
 	int pos = cache_name_pos(path, strlen(path));
-	if (pos < 0) {
-		pos = -pos-1;
+	if (pos >= 0) {
 		active_nr--;
 		if (pos < active_nr)
-			memmove(active_cache + pos, active_cache + pos + 1, (active_nr - pos - 1) * sizeof(struct cache_entry *));
+			memmove(active_cache + pos, active_cache + pos + 1, (active_nr - pos) * sizeof(struct cache_entry *));
 	}
 	return 0;
 }
@@ -305,10 +323,11 @@ int add_cache_entry(struct cache_entry *ce, int ok_to_add)
 	pos = cache_name_pos(ce->name, ce->namelen);
 
 	/* existing match? Just replace it */
-	if (pos < 0) {
-		active_cache[-pos-1] = ce;
+	if (pos >= 0) {
+		active_cache[pos] = ce;
 		return 0;
 	}
+	pos = -pos-1;
 
 	if (!ok_to_add)
 		return -1;
@@ -362,7 +381,7 @@ int read_cache(void)
 		sha1_file_directory = DEFAULT_DB_ENVIRONMENT;
 	if (access(sha1_file_directory, X_OK) < 0)
 		return error("no access to SHA1 file directory");
-	fd = open(".dircache/index", O_RDONLY);
+	fd = open(".git/index", O_RDONLY);
 	if (fd < 0)
 		return (errno == ENOENT) ? 0 : error("open failed");