Merge branch 'lt/dirwalk'

[git.git] / read-cache.c

diff --git a/read-cache.c b/read-cache.c
index e8fa6d0..32ba917 100644 (file)
--- a/read-cache.c
+++ b/read-cache.c
@@ -562,6 +562,123 @@ int add_cache_entry(struct cache_entry *ce, int option)
        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+ * out of date.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;