* Copyright (C) Linus Torvalds, 2005
*/
#include "cache.h"
+#include "cache-tree.h"
+
+/* Index extensions.
+ *
+ * The first letter should be 'A'..'Z' for extensions that are not
+ * necessary for a correct operation (i.e. optimization data).
+ * When new extensions are added that _needs_ to be understood in
+ * order to correctly interpret the index file, pick character that
+ * is outside the range, to cause the reader to abort.
+ */
+
+#define CACHE_EXT(s) ( (s[0]<<24)|(s[1]<<16)|(s[2]<<8)|(s[3]) )
+#define CACHE_EXT_TREE 0x54524545 /* "TREE" */
struct cache_entry **active_cache = NULL;
static time_t index_file_timestamp;
unsigned int active_nr = 0, active_alloc = 0, active_cache_changed = 0;
+struct cache_tree *active_cache_tree = NULL;
+
+int cache_errno = 0;
+
+static void *cache_mmap = NULL;
+static size_t cache_mmap_size = 0;
+
/*
* This only updates the "non-critical" parts of the directory
* cache, ie the parts that aren't tracked by GIT, and only used
unsigned char sha1[20];
if (!index_fd(sha1, fd, st, 0, NULL))
match = memcmp(sha1, ce->sha1, 20);
- close(fd);
+ /* index_fd() closed the file descriptor already */
}
return match;
}
return changed;
}
-int ce_match_stat(struct cache_entry *ce, struct stat *st, int ignore_valid)
+int ce_match_stat(struct cache_entry *ce, struct stat *st, int options)
{
unsigned int changed;
+ int ignore_valid = options & 01;
+ int assume_racy_is_modified = options & 02;
/*
* If it's marked as always valid in the index, it's
*/
if (!changed &&
index_file_timestamp &&
- index_file_timestamp <= ntohl(ce->ce_mtime.sec))
- changed |= ce_modified_check_fs(ce, st);
+ index_file_timestamp <= ntohl(ce->ce_mtime.sec)) {
+ if (assume_racy_is_modified)
+ changed |= DATA_CHANGED;
+ else
+ changed |= ce_modified_check_fs(ce, st);
+ }
return changed;
}
return 0;
}
+int add_file_to_index(const char *path, int verbose)
+{
+ int size, namelen;
+ struct stat st;
+ struct cache_entry *ce;
+
+ if (lstat(path, &st))
+ die("%s: unable to stat (%s)", path, strerror(errno));
+
+ if (!S_ISREG(st.st_mode) && !S_ISLNK(st.st_mode))
+ die("%s: can only add regular files or symbolic links", path);
+
+ namelen = strlen(path);
+ size = cache_entry_size(namelen);
+ ce = xcalloc(1, size);
+ memcpy(ce->name, path, namelen);
+ ce->ce_flags = htons(namelen);
+ fill_stat_cache_info(ce, &st);
+
+ ce->ce_mode = create_ce_mode(st.st_mode);
+ if (!trust_executable_bit) {
+ /* If there is an existing entry, pick the mode bits
+ * from it.
+ */
+ int pos = cache_name_pos(path, namelen);
+ if (pos >= 0)
+ ce->ce_mode = active_cache[pos]->ce_mode;
+ }
+
+ if (index_path(ce->sha1, path, &st, 1))
+ die("unable to index file %s", path);
+ if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD))
+ die("unable to add %s to index",path);
+ if (verbose)
+ printf("add '%s'\n", path);
+ cache_tree_invalidate_path(active_cache_tree, path);
+ return 0;
+}
+
int ce_same_name(struct cache_entry *a, struct cache_entry *b)
{
int len = ce_namelen(a);
return 0;
}
+/*
+ * We fundamentally don't like some paths: we don't want
+ * dot or dot-dot anywhere, and for obvious reasons don't
+ * want to recurse into ".git" either.
+ *
+ * Also, we don't want double slashes or slashes at the
+ * end that can make pathnames ambiguous.
+ */
+static int verify_dotfile(const char *rest)
+{
+ /*
+ * The first character was '.', but that
+ * has already been discarded, we now test
+ * the rest.
+ */
+ switch (*rest) {
+ /* "." is not allowed */
+ case '\0': case '/':
+ return 0;
+
+ /*
+ * ".git" followed by NUL or slash is bad. This
+ * shares the path end test with the ".." case.
+ */
+ case 'g':
+ if (rest[1] != 'i')
+ break;
+ if (rest[2] != 't')
+ break;
+ rest += 2;
+ /* fallthrough */
+ case '.':
+ if (rest[1] == '\0' || rest[1] == '/')
+ return 0;
+ }
+ return 1;
+}
+
+int verify_path(const char *path)
+{
+ char c;
+
+ goto inside;
+ for (;;) {
+ if (!c)
+ return 1;
+ if (c == '/') {
+inside:
+ c = *path++;
+ switch (c) {
+ default:
+ continue;
+ case '/': case '\0':
+ break;
+ case '.':
+ if (verify_dotfile(path))
+ continue;
+ }
+ return 0;
+ }
+ c = *path++;
+ }
+}
+
/*
* Do we have another file that has the beginning components being a
* proper superset of the name we're trying to add?
if (!ok_to_add)
return -1;
+ if (!verify_path(ce->name))
+ return -1;
if (!skip_df_check &&
check_file_directory_conflict(ce, pos, ok_to_replace)) {
return 0;
}
-static int verify_hdr(struct cache_header *hdr, unsigned long size, unsigned char *sha1)
+/*
+ * "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 "git-read-tree",
+ * to link up the stat cache details with the proper files.
+ */
+struct cache_entry *refresh_cache_entry(struct cache_entry *ce, int really)
+{
+ struct stat st;
+ struct cache_entry *updated;
+ int changed, size;
+
+ if (lstat(ce->name, &st) < 0) {
+ cache_errno = errno;
+ return NULL;
+ }
+
+ changed = ce_match_stat(ce, &st, really);
+ if (!changed) {
+ if (really && assume_unchanged &&
+ !(ce->ce_flags & htons(CE_VALID)))
+ ; /* mark this one VALID again */
+ else
+ return ce;
+ }
+
+ if (ce_modified(ce, &st, really)) {
+ cache_errno = EINVAL;
+ return NULL;
+ }
+
+ size = ce_size(ce);
+ updated = xmalloc(size);
+ memcpy(updated, ce, size);
+ fill_stat_cache_info(updated, &st);
+
+ /* In this case, if really is not set, we should leave
+ * CE_VALID bit alone. Otherwise, paths marked with
+ * --no-assume-unchanged (i.e. things to be edited) will
+ * reacquire CE_VALID bit automatically, which is not
+ * really what we want.
+ */
+ if (!really && assume_unchanged && !(ce->ce_flags & htons(CE_VALID)))
+ updated->ce_flags &= ~htons(CE_VALID);
+
+ return updated;
+}
+
+int refresh_cache(unsigned int flags)
+{
+ int i;
+ int has_errors = 0;
+ int really = (flags & REFRESH_REALLY) != 0;
+ int allow_unmerged = (flags & REFRESH_UNMERGED) != 0;
+ int quiet = (flags & REFRESH_QUIET) != 0;
+ int not_new = (flags & REFRESH_IGNORE_MISSING) != 0;
+
+ for (i = 0; i < active_nr; i++) {
+ struct cache_entry *ce, *new;
+ ce = active_cache[i];
+ if (ce_stage(ce)) {
+ while ((i < active_nr) &&
+ ! strcmp(active_cache[i]->name, ce->name))
+ i++;
+ i--;
+ if (allow_unmerged)
+ continue;
+ printf("%s: needs merge\n", ce->name);
+ has_errors = 1;
+ continue;
+ }
+
+ new = refresh_cache_entry(ce, really);
+ if (new == ce)
+ continue;
+ if (!new) {
+ if (not_new && cache_errno == ENOENT)
+ continue;
+ if (really && cache_errno == EINVAL) {
+ /* If we are doing --really-refresh that
+ * means the index is not valid anymore.
+ */
+ ce->ce_flags &= ~htons(CE_VALID);
+ active_cache_changed = 1;
+ }
+ if (quiet)
+ continue;
+ printf("%s: needs update\n", ce->name);
+ has_errors = 1;
+ continue;
+ }
+ active_cache_changed = 1;
+ /* You can NOT just free active_cache[i] here, since it
+ * might not be necessarily malloc()ed but can also come
+ * from mmap(). */
+ active_cache[i] = new;
+ }
+ return has_errors;
+}
+
+static int verify_hdr(struct cache_header *hdr, unsigned long size)
{
SHA_CTX c;
- unsigned char sha1_buf[20];
- if (!sha1)
- sha1 = sha1_buf;
+ unsigned char sha1[20];
if (hdr->hdr_signature != htonl(CACHE_SIGNATURE))
return error("bad signature");
SHA1_Init(&c);
SHA1_Update(&c, hdr, size - 20);
SHA1_Final(sha1, &c);
- if (memcmp(sha1, (void *)hdr + size - 20, 20))
+ if (memcmp(sha1, (char *) hdr + size - 20, 20))
return error("bad index file sha1 signature");
return 0;
}
-int read_cache_1(unsigned char *cache_sha1)
+static int read_index_extension(const char *ext, void *data, unsigned long sz)
+{
+ switch (CACHE_EXT(ext)) {
+ case CACHE_EXT_TREE:
+ active_cache_tree = cache_tree_read(data, sz);
+ break;
+ default:
+ if (*ext < 'A' || 'Z' < *ext)
+ return error("index uses %.4s extension, which we do not understand",
+ ext);
+ fprintf(stderr, "ignoring %.4s extension\n", ext);
+ break;
+ }
+ return 0;
+}
+
+int read_cache(void)
+{
+ return read_cache_from(get_index_file());
+}
+
+/* remember to discard_cache() before reading a different cache! */
+int read_cache_from(const char *path)
{
int fd, i;
struct stat st;
- unsigned long size, offset;
- void *map;
+ unsigned long offset;
struct cache_header *hdr;
errno = EBUSY;
- if (active_cache)
+ if (cache_mmap)
return active_nr;
errno = ENOENT;
index_file_timestamp = 0;
- fd = open(get_index_file(), O_RDONLY);
+ fd = open(path, O_RDONLY);
if (fd < 0) {
if (errno == ENOENT)
return 0;
die("index file open failed (%s)", strerror(errno));
}
- size = 0; // avoid gcc warning
- map = MAP_FAILED;
+ cache_mmap = MAP_FAILED;
if (!fstat(fd, &st)) {
- size = st.st_size;
+ cache_mmap_size = st.st_size;
errno = EINVAL;
- if (size >= sizeof(struct cache_header) + 20)
- map = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
+ if (cache_mmap_size >= sizeof(struct cache_header) + 20)
+ cache_mmap = mmap(NULL, cache_mmap_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
}
close(fd);
- if (map == MAP_FAILED)
+ if (cache_mmap == MAP_FAILED)
die("index file mmap failed (%s)", strerror(errno));
- hdr = map;
- if (verify_hdr(hdr, size, cache_sha1) < 0)
+ hdr = cache_mmap;
+ if (verify_hdr(hdr, cache_mmap_size) < 0)
goto unmap;
active_nr = ntohl(hdr->hdr_entries);
active_alloc = alloc_nr(active_nr);
- active_cache = calloc(active_alloc, sizeof(struct cache_entry *));
+ active_cache = xcalloc(active_alloc, sizeof(struct cache_entry *));
offset = sizeof(*hdr);
for (i = 0; i < active_nr; i++) {
- struct cache_entry *ce = map + offset;
+ struct cache_entry *ce = (struct cache_entry *) ((char *) cache_mmap + offset);
offset = offset + ce_size(ce);
active_cache[i] = ce;
}
index_file_timestamp = st.st_mtime;
+ while (offset <= cache_mmap_size - 20 - 8) {
+ /* After an array of active_nr index entries,
+ * there can be arbitrary number of extended
+ * sections, each of which is prefixed with
+ * extension name (4-byte) and section length
+ * in 4-byte network byte order.
+ */
+ unsigned long extsize;
+ memcpy(&extsize, (char *) cache_mmap + offset + 4, 4);
+ extsize = ntohl(extsize);
+ if (read_index_extension(((const char *) cache_mmap) + offset,
+ (char *) cache_mmap + offset + 8,
+ extsize) < 0)
+ goto unmap;
+ offset += 8;
+ offset += extsize;
+ }
return active_nr;
unmap:
- munmap(map, size);
+ munmap(cache_mmap, cache_mmap_size);
errno = EINVAL;
die("index file corrupt");
}
static unsigned char write_buffer[WRITE_BUFFER_SIZE];
static unsigned long write_buffer_len;
+static int ce_write_flush(SHA_CTX *context, int fd)
+{
+ unsigned int buffered = write_buffer_len;
+ if (buffered) {
+ SHA1_Update(context, write_buffer, buffered);
+ if (write(fd, write_buffer, buffered) != buffered)
+ return -1;
+ write_buffer_len = 0;
+ }
+ return 0;
+}
+
static int ce_write(SHA_CTX *context, int fd, void *data, unsigned int len)
{
while (len) {
memcpy(write_buffer + buffered, data, partial);
buffered += partial;
if (buffered == WRITE_BUFFER_SIZE) {
- SHA1_Update(context, write_buffer, WRITE_BUFFER_SIZE);
- if (write(fd, write_buffer, WRITE_BUFFER_SIZE) != WRITE_BUFFER_SIZE)
+ write_buffer_len = buffered;
+ if (ce_write_flush(context, fd))
return -1;
buffered = 0;
}
write_buffer_len = buffered;
len -= partial;
- data += partial;
+ data = (char *) data + partial;
}
return 0;
}
-static int ce_flush(SHA_CTX *context, int fd, unsigned char *sha1)
+static int write_index_ext_header(SHA_CTX *context, int fd,
+ unsigned int ext, unsigned int sz)
+{
+ ext = htonl(ext);
+ sz = htonl(sz);
+ return ((ce_write(context, fd, &ext, 4) < 0) ||
+ (ce_write(context, fd, &sz, 4) < 0)) ? -1 : 0;
+}
+
+static int ce_flush(SHA_CTX *context, int fd)
{
unsigned int left = write_buffer_len;
}
/* Append the SHA1 signature at the end */
- SHA1_Final(sha1, context);
- memcpy(write_buffer + left, sha1, 20);
+ SHA1_Final(write_buffer + left, context);
left += 20;
- if (write(fd, write_buffer, left) != left)
- return -1;
- return 0;
+ return (write(fd, write_buffer, left) != left) ? -1 : 0;
}
static void ce_smudge_racily_clean_entry(struct cache_entry *ce)
* $ echo filfre >nitfol
* $ git-update-index --add nitfol
*
- * but it does not. Whe the second update-index runs,
+ * but it does not. When the second update-index runs,
* it notices that the entry "frotz" has the same timestamp
* as index, and if we were to smudge it by resetting its
* size to zero here, then the object name recorded
}
}
-int write_cache_1(int newfd, struct cache_entry **cache, int entries,
- unsigned char *cache_sha1)
+int write_cache(int newfd, struct cache_entry **cache, int entries)
{
SHA_CTX c;
struct cache_header hdr;
- int i, removed;
- int status;
- unsigned char sha1[20];
+ int i, removed, recent;
+ struct stat st;
+ time_t now;
for (i = removed = 0; i < entries; i++)
if (!cache[i]->ce_mode)
if (ce_write(&c, newfd, ce, ce_size(ce)) < 0)
return -1;
}
- status = ce_flush(&c, newfd, sha1);
- if (cache_sha1)
- memcpy(cache_sha1, sha1, 20);
- return status;
-}
-int read_cache(void)
-{
- return read_cache_1(NULL);
-}
+ /* Write extension data here */
+ if (active_cache_tree) {
+ unsigned long sz;
+ void *data = cache_tree_write(active_cache_tree, &sz);
+ if (data &&
+ !write_index_ext_header(&c, newfd, CACHE_EXT_TREE, sz) &&
+ !ce_write(&c, newfd, data, sz))
+ ;
+ else {
+ free(data);
+ return -1;
+ }
+ }
-int write_cache(int newfd, struct cache_entry **cache, int entries)
-{
- return write_cache_1(newfd, cache, entries, NULL);
+ /*
+ * To prevent later ce_match_stat() from always falling into
+ * check_fs(), if we have too many entries that can trigger
+ * racily clean check, we are better off delaying the return.
+ * We arbitrarily say if more than 20 paths or 25% of total
+ * paths are very new, we delay the return until the index
+ * file gets a new timestamp.
+ *
+ * NOTE! NOTE! NOTE!
+ *
+ * This assumes that nobody is touching the working tree while
+ * we are updating the index.
+ */
+
+ /* Make sure that the new index file has st_mtime
+ * that is current enough -- ce_write() batches the data
+ * so it might not have written anything yet.
+ */
+ ce_write_flush(&c, newfd);
+
+ now = fstat(newfd, &st) ? 0 : st.st_mtime;
+ if (now) {
+ recent = 0;
+ for (i = 0; i < entries; i++) {
+ struct cache_entry *ce = cache[i];
+ time_t entry_time = (time_t) ntohl(ce->ce_mtime.sec);
+ if (!ce->ce_mode)
+ continue;
+ if (now && now <= entry_time)
+ recent++;
+ }
+ if (20 < recent && entries <= recent * 4) {
+#if 0
+ fprintf(stderr, "entries %d\n", entries);
+ fprintf(stderr, "recent %d\n", recent);
+ fprintf(stderr, "now %lu\n", now);
+#endif
+ while (!fstat(newfd, &st) && st.st_mtime <= now) {
+ off_t where = lseek(newfd, 0, SEEK_CUR);
+ sleep(1);
+ if ((where == (off_t) -1) ||
+ (write(newfd, "", 1) != 1) ||
+ (lseek(newfd, -1, SEEK_CUR) != where) ||
+ ftruncate(newfd, where))
+ break;
+ }
+ }
+ }
+ return ce_flush(&c, newfd);
}