* 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;
+
/*
* This only updates the "non-critical" parts of the directory
* cache, ie the parts that aren't tracked by GIT, and only used
return 0;
}
+/* Three functions to allow overloaded pointer return; see linux/err.h */
+static inline void *ERR_PTR(long error)
+{
+ return (void *) error;
+}
+
+static inline long PTR_ERR(const void *ptr)
+{
+ return (long) ptr;
+}
+
+static inline long IS_ERR(const void *ptr)
+{
+ return (unsigned long)ptr > (unsigned long)-1000L;
+}
+
+/*
+ * "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+ * out of date.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.
+ */
+static struct cache_entry *refresh_entry(struct cache_entry *ce, int really)
+{
+ struct stat st;
+ struct cache_entry *updated;
+ int changed, size;
+
+ if (lstat(ce->name, &st) < 0)
+ return ERR_PTR(-errno);
+
+ 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 NULL;
+ }
+
+ if (ce_modified(ce, &st, really))
+ return ERR_PTR(-EINVAL);
+
+ 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_entry(ce, really);
+ if (!new)
+ continue;
+ if (IS_ERR(new)) {
+ if (not_new && PTR_ERR(new) == -ENOENT)
+ continue;
+ if (really && PTR_ERR(new) == -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;
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;
}
+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)
{
int fd, i;
offset = sizeof(*hdr);
for (i = 0; i < active_nr; i++) {
- struct cache_entry *ce = map + offset;
+ struct cache_entry *ce = (struct cache_entry *) ((char *) map + offset);
offset = offset + ce_size(ce);
active_cache[i] = ce;
}
index_file_timestamp = st.st_mtime;
+ while (offset <= 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 *) map + offset + 4, 4);
+ extsize = ntohl(extsize);
+ if (read_index_extension(((const char *) map) + offset,
+ (char *) map + offset + 8,
+ extsize) < 0)
+ goto unmap;
+ offset += 8;
+ offset += extsize;
+ }
return active_nr;
unmap:
}
write_buffer_len = buffered;
len -= partial;
- data += partial;
+ data = (char *) data + partial;
}
return 0;
}
+static int write_index_ext_header(SHA_CTX *context, int fd,
+ unsigned int ext, unsigned int sz)
+{
+ ext = htonl(ext);
+ sz = htonl(sz);
+ if ((ce_write(context, fd, &ext, 4) < 0) ||
+ (ce_write(context, fd, &sz, 4) < 0))
+ return -1;
+ return 0;
+}
+
static int ce_flush(SHA_CTX *context, int fd)
{
unsigned int left = write_buffer_len;
if (ce_write(&c, newfd, ce, ce_size(ce)) < 0)
return -1;
}
+
+ /* 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;
+ }
+ }
return ce_flush(&c, newfd);
}