X-Git-Url: https://git.octo.it/?a=blobdiff_plain;f=update-cache.c;h=893ba8679d5764ba84627558d567268ff2500558;hb=20d37ef67286e5131d2333d7b4662bc70f9d4937;hp=942e309fe63f0eeffc0e24fa70027eaa39cc1a56;hpb=121481abf8d752ef871821d4ab9a3747595d86ae;p=git.git

diff --git a/update-cache.c b/update-cache.c
index 942e309f..893ba867 100644
--- a/update-cache.c
+++ b/update-cache.c
@@ -3,6 +3,7 @@
  *
  * Copyright (C) Linus Torvalds, 2005
  */
+#include <signal.h>
 #include "cache.h"
 
 /*
@@ -12,123 +13,237 @@
  * like "update-cache *" and suddenly having all the object
  * files be revision controlled.
  */
-static int allow_add = 0, allow_remove = 0;
+static int allow_add = 0, allow_remove = 0, not_new = 0;
 
-static int index_fd(const char *path, int namelen, struct cache_entry *ce, int fd, struct stat *st)
+/*
+ * update-cache --refresh may not touch anything at all, in which case
+ * writing 1.6MB of the same thing is a waste.
+ */
+static int cache_changed = 0;
+
+/* Three functions to allow overloaded pointer return; see linux/err.h */
+static inline void *ERR_PTR(long error)
 {
-	z_stream stream;
-	int max_out_bytes = namelen + st->st_size + 200;
-	void *out = malloc(max_out_bytes);
-	void *metadata = malloc(namelen + 200);
-	void *in = mmap(NULL, st->st_size, PROT_READ, MAP_PRIVATE, fd, 0);
-	SHA_CTX c;
-
-	close(fd);
-	if (!out || (int)(long)in == -1)
-		return -1;
+	return (void *) error;
+}
 
-	memset(&stream, 0, sizeof(stream));
-	deflateInit(&stream, Z_BEST_COMPRESSION);
+static inline long PTR_ERR(const void *ptr)
+{
+	return (long) ptr;
+}
 
-	/*
-	 * ASCII size + nul byte
-	 */	
-	stream.next_in = metadata;
-	stream.avail_in = 1+sprintf(metadata, "blob %lu", (unsigned long) st->st_size);
-	stream.next_out = out;
-	stream.avail_out = max_out_bytes;
-	while (deflate(&stream, 0) == Z_OK)
-		/* nothing */;
+static inline long IS_ERR(const void *ptr)
+{
+	return (unsigned long)ptr > (unsigned long)-1000L;
+}
 
-	/*
-	 * File content
-	 */
-	stream.next_in = in;
-	stream.avail_in = st->st_size;
-	while (deflate(&stream, Z_FINISH) == Z_OK)
-		/*nothing */;
-
-	deflateEnd(&stream);
-	
-	SHA1_Init(&c);
-	SHA1_Update(&c, out, stream.total_out);
-	SHA1_Final(ce->sha1, &c);
-
-	return write_sha1_buffer(ce->sha1, out, stream.total_out);
+/*
+ * This only updates the "non-critical" parts of the directory
+ * cache, ie the parts that aren't tracked by GIT, and only used
+ * to validate the cache.
+ */
+static void fill_stat_cache_info(struct cache_entry *ce, struct stat *st)
+{
+	ce->ce_ctime.sec = htonl(st->st_ctime);
+	ce->ce_mtime.sec = htonl(st->st_mtime);
+#ifdef NSEC
+	ce->ce_ctime.nsec = htonl(st->st_ctim.tv_nsec);
+	ce->ce_mtime.nsec = htonl(st->st_mtim.tv_nsec);
+#endif
+	ce->ce_dev = htonl(st->st_dev);
+	ce->ce_ino = htonl(st->st_ino);
+	ce->ce_uid = htonl(st->st_uid);
+	ce->ce_gid = htonl(st->st_gid);
+	ce->ce_size = htonl(st->st_size);
 }
 
-static int add_file_to_cache(char *path)
+static int add_file_to_cache_1(char *path)
 {
 	int size, namelen;
 	struct cache_entry *ce;
 	struct stat st;
 	int fd;
+	unsigned int len;
+	char target[1024];
 
-	fd = open(path, O_RDONLY);
-	if (fd < 0) {
-		if (errno == ENOENT) {
+	if (lstat(path, &st) < 0) {
+		if (errno == ENOENT || errno == ENOTDIR) {
 			if (allow_remove)
 				return remove_file_from_cache(path);
 		}
 		return -1;
 	}
-	if (fstat(fd, &st) < 0) {
-		close(fd);
-		return -1;
-	}
 	namelen = strlen(path);
 	size = cache_entry_size(namelen);
-	ce = malloc(size);
+	ce = xmalloc(size);
 	memset(ce, 0, size);
 	memcpy(ce->name, path, namelen);
-	ce->ctime.sec = st.st_ctime;
-	ce->ctime.nsec = st.st_ctim.tv_nsec;
-	ce->mtime.sec = st.st_mtime;
-	ce->mtime.nsec = st.st_mtim.tv_nsec;
-	ce->st_dev = st.st_dev;
-	ce->st_ino = st.st_ino;
-	ce->st_mode = st.st_mode;
-	ce->st_uid = st.st_uid;
-	ce->st_gid = st.st_gid;
-	ce->st_size = st.st_size;
-	ce->namelen = namelen;
-
-	if (index_fd(path, namelen, ce, fd, &st) < 0)
+	fill_stat_cache_info(ce, &st);
+	ce->ce_mode = create_ce_mode(st.st_mode);
+	ce->ce_flags = htons(namelen);
+	switch (st.st_mode & S_IFMT) {
+	case S_IFREG:
+		fd = open(path, O_RDONLY);
+		if (fd < 0)
+			return -1;
+		if (index_fd(ce->sha1, fd, &st) < 0)
+			return -1;
+		break;
+	case S_IFLNK:
+		len = readlink(path, target, sizeof(target));
+		if (len == -1 || len+1 > sizeof(target))
+			return -1;
+		if (write_sha1_file(target, len, "blob", ce->sha1))
+			return -1;
+		break;
+	default:
 		return -1;
-
+	}
+	if (!cache_changed) {
+		/* If we have not smudged the cache, be careful
+		 * to keep it clean.  Find out if we have a matching
+		 * cache entry that add_cache_entry would replace with,
+		 * and if it matches then do not bother calling it.
+		 */
+		int pos = cache_name_pos(ce->name, namelen);
+		if ((0 <= pos) &&
+		    !memcmp(active_cache[pos], ce, sizeof(*ce))) {
+			free(ce);
+			/* magic to tell add_file_to_cache that
+			 * we have not updated anything.
+			 */
+			return 999;
+		}
+	}
 	return add_cache_entry(ce, allow_add);
 }
 
-static void refresh_entry(struct cache_entry *ce)
+static int add_file_to_cache(char *path)
 {
+	int ret = add_file_to_cache_1(path);
+	if (ret == 0)
+		cache_changed = 1;
+	else if (ret == 999)
+		ret = 0;
+	return ret;
+}
+
+static int match_data(int fd, void *buffer, unsigned long size)
+{
+	while (size) {
+		char compare[1024];
+		int ret = read(fd, compare, sizeof(compare));
+
+		if (ret <= 0 || ret > size || memcmp(buffer, compare, ret))
+			return -1;
+		size -= ret;
+		buffer += ret;
+	}
+	return 0;
+}
+
+static int compare_data(struct cache_entry *ce, unsigned long expected_size)
+{
+	int match = -1;
+	int fd = open(ce->name, O_RDONLY);
+
+	if (fd >= 0) {
+		void *buffer;
+		unsigned long size;
+		char type[10];
+
+		buffer = read_sha1_file(ce->sha1, type, &size);
+		if (buffer) {
+			if (size == expected_size && !strcmp(type, "blob"))
+				match = match_data(fd, buffer, size);
+			free(buffer);
+		}
+		close(fd);
+	}
+	return match;
+}
+
+/*
+ * "refresh" does not calculate a new sha1 file or bring the
+ * cache up-to-date for mode/content changes. But what it
+ * _does_ do is to "re-match" the stat information of a file
+ * with the cache, so that you can refresh the cache for a
+ * file that hasn't been changed but where the stat entry is
+ * out of date.
+ *
+ * For example, you'd want to do this after doing a "read-tree",
+ * to link up the stat cache details with the proper files.
+ */
+static struct cache_entry *refresh_entry(struct cache_entry *ce)
+{
+	struct stat st;
+	struct cache_entry *updated;
+	int changed, size;
+
+	if (lstat(ce->name, &st) < 0)
+		return ERR_PTR(-errno);
+
+	changed = cache_match_stat(ce, &st);
+	if (!changed)
+		return ce;
+
 	/*
-	 * This is really not the right way to do it, but
-	 * add_file_to_cache() does do the right thing.
-	 *
-	 * We should really just update the cache
-	 * entry in-place, I think. With this approach we
-	 * end up allocating a new one, searching for where
-	 * to insert it etc etc crud.
+	 * If the mode or type has changed, there's no point in trying
+	 * to refresh the entry - it's not going to match
 	 */
-	add_file_to_cache(ce->name);
+	if (changed & (MODE_CHANGED | TYPE_CHANGED))
+		return ERR_PTR(-EINVAL);
+
+	if (compare_data(ce, st.st_size))
+		return ERR_PTR(-EINVAL);
+
+	cache_changed = 1;
+	size = ce_size(ce);
+	updated = xmalloc(size);
+	memcpy(updated, ce, size);
+	fill_stat_cache_info(updated, &st);
+	return updated;
 }
 
-static void refresh_cache(void)
+static int refresh_cache(void)
 {
 	int i;
+	int has_errors = 0;
+
+	for (i = 0; i < active_nr; i++) {
+		struct cache_entry *ce, *new;
+		ce = active_cache[i];
+		if (ce_stage(ce)) {
+			printf("%s: needs merge\n", ce->name);
+			has_errors = 1;
+			while ((i < active_nr) &&
+			       ! strcmp(active_cache[i]->name, ce->name))
+				i++;
+			i--;
+			continue;
+		}
 
-	for (i = 0; i < active_nr; i++)
-		refresh_entry(active_cache[i]);
+		new = refresh_entry(ce);
+		if (IS_ERR(new)) {
+			if (!(not_new && PTR_ERR(new) == -ENOENT)) {
+				printf("%s: needs update\n", ce->name);
+				has_errors = 1;
+			}
+			continue;
+		}
+		active_cache[i] = new;
+	}
+	return has_errors;
 }
 
 /*
  * We fundamentally don't like some paths: we don't want
  * dot or dot-dot anywhere, and in fact, we don't even want
- * any other dot-files (.dircache or anything else). They
+ * any other dot-files (.git or anything else). They
  * are hidden, for chist sake.
  *
  * Also, we don't want double slashes or slashes at the
- * end that can make pathnames ambiguous. 
+ * end that can make pathnames ambiguous.
  */
 static int verify_path(char *path)
 {
@@ -149,22 +264,67 @@ inside:
 	}
 }
 
+static int add_cacheinfo(char *arg1, char *arg2, char *arg3)
+{
+	int size, len;
+	unsigned int mode;
+	unsigned char sha1[20];
+	struct cache_entry *ce;
+
+	if (sscanf(arg1, "%o", &mode) != 1)
+		return -1;
+	if (get_sha1_hex(arg2, sha1))
+		return -1;
+	if (!verify_path(arg3))
+		return -1;
+
+	cache_changed = 1;
+	len = strlen(arg3);
+	size = cache_entry_size(len);
+	ce = xmalloc(size);
+	memset(ce, 0, size);
+
+	memcpy(ce->sha1, sha1, 20);
+	memcpy(ce->name, arg3, len);
+	ce->ce_flags = htons(len);
+	ce->ce_mode = create_ce_mode(mode);
+	return add_cache_entry(ce, allow_add);
+}
+
+static const char *lockfile_name = NULL;
+
+static void remove_lock_file(void)
+{
+	if (lockfile_name)
+		unlink(lockfile_name);
+}
+
+static void remove_lock_file_on_signal(int signo)
+{
+	remove_lock_file();
+}
+
 int main(int argc, char **argv)
 {
-	int i, newfd, entries;
+	int i, newfd, entries, has_errors = 0;
 	int allow_options = 1;
+	static char lockfile[MAXPATHLEN+1];
+	const char *indexfile = get_index_file();
+
+	snprintf(lockfile, sizeof(lockfile), "%s.lock", indexfile);
+
+	newfd = open(lockfile, O_RDWR | O_CREAT | O_EXCL, 0600);
+	if (newfd < 0)
+		die("unable to create new cachefile");
+
+	signal(SIGINT, remove_lock_file_on_signal);
+	atexit(remove_lock_file);
+	lockfile_name = lockfile;
 
 	entries = read_cache();
-	if (entries < 0) {
-		perror("cache corrupted");
-		return -1;
-	}
+	if (entries < 0)
+		die("cache corrupted");
 
-	newfd = open(".dircache/index.lock", O_RDWR | O_CREAT | O_EXCL, 0600);
-	if (newfd < 0) {
-		perror("unable to create new cachefile");
-		return -1;
-	}
 	for (i = 1 ; i < argc; i++) {
 		char *path = argv[i];
 
@@ -182,23 +342,44 @@ int main(int argc, char **argv)
 				continue;
 			}
 			if (!strcmp(path, "--refresh")) {
-				refresh_cache();
+				has_errors |= refresh_cache();
 				continue;
 			}
-			usage("unknown option %s", path);
+			if (!strcmp(path, "--cacheinfo")) {
+				if (i+3 >= argc || add_cacheinfo(argv[i+1], argv[i+2], argv[i+3]))
+					die("update-cache: --cacheinfo <mode> <sha1> <path>");
+				i += 3;
+				continue;
+			}
+			if (!strcmp(path, "--force-remove")) {
+				if (argc <= i + 1)
+					die("update-cache: --force-remove <path>");
+				if (remove_file_from_cache(argv[i+1]))
+					die("update-cache: --force-remove cannot remove %s", argv[i+1]);
+				i++;
+				continue;
+			}
+
+			if (!strcmp(path, "--ignore-missing")) {
+				not_new = 1;
+				continue;
+			}
+			die("unknown option %s", path);
 		}
 		if (!verify_path(path)) {
 			fprintf(stderr, "Ignoring path %s\n", argv[i]);
 			continue;
 		}
-		if (add_file_to_cache(path)) {
-			fprintf(stderr, "Unable to add %s to database\n", path);
-			goto out;
-		}
+		if (add_file_to_cache(path))
+			die("Unable to add %s to database", path);
 	}
-	if (!write_cache(newfd, active_cache, active_nr) && !rename(".dircache/index.lock", ".dircache/index"))
-		return 0;
-out:
-	unlink(".dircache/index.lock");
-	return 0;
+
+	if (!cache_changed)
+		unlink(lockfile);
+	else if (write_cache(newfd, active_cache, active_nr) ||
+		 rename(lockfile, indexfile))
+		die("Unable to write new cachefile");
+
+	lockfile_name = NULL;
+	return has_errors ? 1 : 0;
 }