*/
#include "cache.h"
-static int cache_name_compare(const char *name1, int len1, const char *name2, int len2)
-{
- int len = len1 < len2 ? len1 : len2;
- int cmp;
-
- cmp = memcmp(name1, name2, len);
- if (cmp)
- return cmp;
- if (len1 < len2)
- return -1;
- if (len1 > len2)
- return 1;
- return 0;
-}
-
-static int cache_name_pos(const char *name, int namelen)
-{
- int first, last;
-
- first = 0;
- last = active_nr;
- while (last > first) {
- int next = (last + first) >> 1;
- struct cache_entry *ce = active_cache[next];
- int cmp = cache_name_compare(name, namelen, ce->name, ce->namelen);
- if (!cmp)
- return -next-1;
- if (cmp < 0) {
- last = next;
- continue;
- }
- first = next+1;
- }
- return first;
-}
-
-static int remove_file_from_cache(char *path)
-{
- int pos = cache_name_pos(path, strlen(path));
- if (pos < 0) {
- pos = -pos-1;
- active_nr--;
- if (pos < active_nr)
- memmove(active_cache + pos, active_cache + pos + 1, (active_nr - pos - 1) * sizeof(struct cache_entry *));
- }
-}
-
-static int add_cache_entry(struct cache_entry *ce)
-{
- int pos;
-
- pos = cache_name_pos(ce->name, ce->namelen);
-
- /* existing match? Just replace it */
- if (pos < 0) {
- active_cache[-pos-1] = ce;
- return 0;
- }
-
- /* Make sure the array is big enough .. */
- if (active_nr == active_alloc) {
- active_alloc = alloc_nr(active_alloc);
- active_cache = realloc(active_cache, active_alloc * sizeof(struct cache_entry *));
- }
-
- /* Add it in.. */
- active_nr++;
- if (active_nr > pos)
- memmove(active_cache + pos + 1, active_cache + pos, (active_nr - pos - 1) * sizeof(ce));
- active_cache[pos] = ce;
- return 0;
-}
+/*
+ * Default to not allowing changes to the list of files. The
+ * tool doesn't actually care, but this makes it harder to add
+ * files to the revision control by mistake by doing something
+ * like "update-cache *" and suddenly having all the object
+ * files be revision controlled.
+ */
+static int allow_add = 0, allow_remove = 0;
static int index_fd(const char *path, int namelen, struct cache_entry *ce, int fd, struct stat *st)
{
z_stream stream;
- int max_out_bytes = namelen + st->st_size + 200;
+ unsigned long size = st->st_size;
+ int max_out_bytes = namelen + 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);
+ void *in;
SHA_CTX c;
+ in = "";
+ if (size)
+ in = mmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
close(fd);
if (!out || (int)(long)in == -1)
return -1;
* ASCII size + nul byte
*/
stream.next_in = metadata;
- stream.avail_in = 1+sprintf(metadata, "blob %lu", (unsigned long) st->st_size);
+ stream.avail_in = 1+sprintf(metadata, "blob %lu", size);
stream.next_out = out;
stream.avail_out = max_out_bytes;
while (deflate(&stream, 0) == Z_OK)
* File content
*/
stream.next_in = in;
- stream.avail_in = st->st_size;
+ stream.avail_in = size;
while (deflate(&stream, Z_FINISH) == Z_OK)
/*nothing */;
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->ctime.sec = st->st_ctime;
+#ifdef NSEC
+ ce->ctime.nsec = st->st_ctim.tv_nsec;
+#endif
+ ce->mtime.sec = st->st_mtime;
+#ifdef NSEC
+ ce->mtime.nsec = st->st_mtim.tv_nsec;
+#endif
+ ce->st_dev = st->st_dev;
+ ce->st_ino = st->st_ino;
+ ce->st_uid = st->st_uid;
+ ce->st_gid = st->st_gid;
+}
+
static int add_file_to_cache(char *path)
{
int size, namelen;
fd = open(path, O_RDONLY);
if (fd < 0) {
- if (errno == ENOENT)
- return remove_file_from_cache(path);
+ if (errno == ENOENT) {
+ if (allow_remove)
+ return remove_file_from_cache(path);
+ }
return -1;
}
if (fstat(fd, &st) < 0) {
ce = malloc(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;
+ fill_stat_cache_info(ce, &st);
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)
return -1;
- return add_cache_entry(ce);
+ return add_cache_entry(ce, allow_add);
}
-static int write_cache(int newfd, struct cache_entry **cache, int entries)
+static int match_data(int fd, void *buffer, unsigned long size)
{
- SHA_CTX c;
- struct cache_header hdr;
- int i;
+ while (size) {
+ char compare[1024];
+ int ret = read(fd, compare, sizeof(compare));
- hdr.signature = CACHE_SIGNATURE;
- hdr.version = 1;
- hdr.entries = entries;
+ if (ret <= 0 || ret > size || memcmp(buffer, compare, ret))
+ return -1;
+ size -= ret;
+ buffer += ret;
+ }
+ return 0;
+}
- SHA1_Init(&c);
- SHA1_Update(&c, &hdr, offsetof(struct cache_header, sha1));
- for (i = 0; i < entries; i++) {
- struct cache_entry *ce = cache[i];
- int size = ce_size(ce);
- SHA1_Update(&c, ce, size);
+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);
}
- SHA1_Final(hdr.sha1, &c);
+ return match;
+}
- if (write(newfd, &hdr, sizeof(hdr)) != sizeof(hdr))
- return -1;
+/*
+ * "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;
- for (i = 0; i < entries; i++) {
- struct cache_entry *ce = cache[i];
- int size = ce_size(ce);
- if (write(newfd, ce, size) != size)
- return -1;
+ if (stat(ce->name, &st) < 0)
+ return NULL;
+
+ changed = cache_match_stat(ce, &st);
+ if (!changed)
+ return ce;
+
+ /*
+ * If the mode has changed, there's no point in trying
+ * to refresh the entry - it's not going to match
+ */
+ if (changed & MODE_CHANGED)
+ return NULL;
+
+ if (compare_data(ce, st.st_size))
+ return NULL;
+
+ size = ce_size(ce);
+ updated = malloc(size);
+ memcpy(updated, ce, size);
+ fill_stat_cache_info(updated, &st);
+ updated->st_size = st.st_size;
+ return updated;
+}
+
+static void refresh_cache(void)
+{
+ int i;
+
+ for (i = 0; i < active_nr; i++) {
+ struct cache_entry *ce = active_cache[i];
+ struct cache_entry *new = refresh_entry(ce);
+
+ if (!new) {
+ printf("%s: needs update\n", ce->name);
+ continue;
+ }
+ active_cache[i] = new;
}
- return 0;
-}
+}
/*
* 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)
{
}
}
+static int remove_lock = 0;
+
+static void remove_lock_file(void)
+{
+ if (remove_lock)
+ unlink(".git/index.lock");
+}
+
int main(int argc, char **argv)
{
int i, newfd, entries;
+ int allow_options = 1;
+
+ newfd = open(".git/index.lock", O_RDWR | O_CREAT | O_EXCL, 0600);
+ if (newfd < 0)
+ die("unable to create new cachefile");
+
+ atexit(remove_lock_file);
+ remove_lock = 1;
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];
+
+ if (allow_options && *path == '-') {
+ if (!strcmp(path, "--")) {
+ allow_options = 0;
+ continue;
+ }
+ if (!strcmp(path, "--add")) {
+ allow_add = 1;
+ continue;
+ }
+ if (!strcmp(path, "--remove")) {
+ allow_remove = 1;
+ continue;
+ }
+ if (!strcmp(path, "--refresh")) {
+ refresh_cache();
+ 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");
+ if (write_cache(newfd, active_cache, active_nr) ||
+ rename(".git/index.lock", ".git/index"))
+ die("Unable to write new cachefile");
+
+ remove_lock = 0;
+ return 0;
}
projects / git.git / blobdiff