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-rw-r--r--fsck.c332
1 files changed, 332 insertions, 0 deletions
diff --git a/fsck.c b/fsck.c
new file mode 100644
index 000000000..97f76c581
--- /dev/null
+++ b/fsck.c
@@ -0,0 +1,332 @@
+#include "cache.h"
+#include "object.h"
+#include "blob.h"
+#include "tree.h"
+#include "tree-walk.h"
+#include "commit.h"
+#include "tag.h"
+#include "fsck.h"
+
+static int fsck_walk_tree(struct tree *tree, fsck_walk_func walk, void *data)
+{
+ struct tree_desc desc;
+ struct name_entry entry;
+ int res = 0;
+
+ if (parse_tree(tree))
+ return -1;
+
+ init_tree_desc(&desc, tree->buffer, tree->size);
+ while (tree_entry(&desc, &entry)) {
+ int result;
+
+ if (S_ISGITLINK(entry.mode))
+ continue;
+ if (S_ISDIR(entry.mode))
+ result = walk(&lookup_tree(entry.sha1)->object, OBJ_TREE, data);
+ else if (S_ISREG(entry.mode) || S_ISLNK(entry.mode))
+ result = walk(&lookup_blob(entry.sha1)->object, OBJ_BLOB, data);
+ else {
+ result = error("in tree %s: entry %s has bad mode %.6o\n",
+ sha1_to_hex(tree->object.sha1), entry.path, entry.mode);
+ }
+ if (result < 0)
+ return result;
+ if (!res)
+ res = result;
+ }
+ return res;
+}
+
+static int fsck_walk_commit(struct commit *commit, fsck_walk_func walk, void *data)
+{
+ struct commit_list *parents;
+ int res;
+ int result;
+
+ if (parse_commit(commit))
+ return -1;
+
+ result = walk((struct object *)commit->tree, OBJ_TREE, data);
+ if (result < 0)
+ return result;
+ res = result;
+
+ parents = commit->parents;
+ while (parents) {
+ result = walk((struct object *)parents->item, OBJ_COMMIT, data);
+ if (result < 0)
+ return result;
+ if (!res)
+ res = result;
+ parents = parents->next;
+ }
+ return res;
+}
+
+static int fsck_walk_tag(struct tag *tag, fsck_walk_func walk, void *data)
+{
+ if (parse_tag(tag))
+ return -1;
+ return walk(tag->tagged, OBJ_ANY, data);
+}
+
+int fsck_walk(struct object *obj, fsck_walk_func walk, void *data)
+{
+ if (!obj)
+ return -1;
+ switch (obj->type) {
+ case OBJ_BLOB:
+ return 0;
+ case OBJ_TREE:
+ return fsck_walk_tree((struct tree *)obj, walk, data);
+ case OBJ_COMMIT:
+ return fsck_walk_commit((struct commit *)obj, walk, data);
+ case OBJ_TAG:
+ return fsck_walk_tag((struct tag *)obj, walk, data);
+ default:
+ error("Unknown object type for %s", sha1_to_hex(obj->sha1));
+ return -1;
+ }
+}
+
+/*
+ * The entries in a tree are ordered in the _path_ order,
+ * which means that a directory entry is ordered by adding
+ * a slash to the end of it.
+ *
+ * So a directory called "a" is ordered _after_ a file
+ * called "a.c", because "a/" sorts after "a.c".
+ */
+#define TREE_UNORDERED (-1)
+#define TREE_HAS_DUPS (-2)
+
+static int verify_ordered(unsigned mode1, const char *name1, unsigned mode2, const char *name2)
+{
+ int len1 = strlen(name1);
+ int len2 = strlen(name2);
+ int len = len1 < len2 ? len1 : len2;
+ unsigned char c1, c2;
+ int cmp;
+
+ cmp = memcmp(name1, name2, len);
+ if (cmp < 0)
+ return 0;
+ if (cmp > 0)
+ return TREE_UNORDERED;
+
+ /*
+ * Ok, the first <len> characters are the same.
+ * Now we need to order the next one, but turn
+ * a '\0' into a '/' for a directory entry.
+ */
+ c1 = name1[len];
+ c2 = name2[len];
+ if (!c1 && !c2)
+ /*
+ * git-write-tree used to write out a nonsense tree that has
+ * entries with the same name, one blob and one tree. Make
+ * sure we do not have duplicate entries.
+ */
+ return TREE_HAS_DUPS;
+ if (!c1 && S_ISDIR(mode1))
+ c1 = '/';
+ if (!c2 && S_ISDIR(mode2))
+ c2 = '/';
+ return c1 < c2 ? 0 : TREE_UNORDERED;
+}
+
+static int fsck_tree(struct tree *item, int strict, fsck_error error_func)
+{
+ int retval;
+ int has_full_path = 0;
+ int has_empty_name = 0;
+ int has_zero_pad = 0;
+ int has_bad_modes = 0;
+ int has_dup_entries = 0;
+ int not_properly_sorted = 0;
+ struct tree_desc desc;
+ unsigned o_mode;
+ const char *o_name;
+ const unsigned char *o_sha1;
+
+ init_tree_desc(&desc, item->buffer, item->size);
+
+ o_mode = 0;
+ o_name = NULL;
+ o_sha1 = NULL;
+
+ while (desc.size) {
+ unsigned mode;
+ const char *name;
+ const unsigned char *sha1;
+
+ sha1 = tree_entry_extract(&desc, &name, &mode);
+
+ if (strchr(name, '/'))
+ has_full_path = 1;
+ if (!*name)
+ has_empty_name = 1;
+ has_zero_pad |= *(char *)desc.buffer == '0';
+ update_tree_entry(&desc);
+
+ switch (mode) {
+ /*
+ * Standard modes..
+ */
+ case S_IFREG | 0755:
+ case S_IFREG | 0644:
+ case S_IFLNK:
+ case S_IFDIR:
+ case S_IFGITLINK:
+ break;
+ /*
+ * This is nonstandard, but we had a few of these
+ * early on when we honored the full set of mode
+ * bits..
+ */
+ case S_IFREG | 0664:
+ if (!strict)
+ break;
+ default:
+ has_bad_modes = 1;
+ }
+
+ if (o_name) {
+ switch (verify_ordered(o_mode, o_name, mode, name)) {
+ case TREE_UNORDERED:
+ not_properly_sorted = 1;
+ break;
+ case TREE_HAS_DUPS:
+ has_dup_entries = 1;
+ break;
+ default:
+ break;
+ }
+ }
+
+ o_mode = mode;
+ o_name = name;
+ o_sha1 = sha1;
+ }
+
+ retval = 0;
+ if (has_full_path)
+ retval += error_func(&item->object, FSCK_WARN, "contains full pathnames");
+ if (has_empty_name)
+ retval += error_func(&item->object, FSCK_WARN, "contains empty pathname");
+ if (has_zero_pad)
+ retval += error_func(&item->object, FSCK_WARN, "contains zero-padded file modes");
+ if (has_bad_modes)
+ retval += error_func(&item->object, FSCK_WARN, "contains bad file modes");
+ if (has_dup_entries)
+ retval += error_func(&item->object, FSCK_ERROR, "contains duplicate file entries");
+ if (not_properly_sorted)
+ retval += error_func(&item->object, FSCK_ERROR, "not properly sorted");
+ return retval;
+}
+
+static int fsck_commit(struct commit *commit, fsck_error error_func)
+{
+ char *buffer = commit->buffer;
+ unsigned char tree_sha1[20], sha1[20];
+ struct commit_graft *graft;
+ int parents = 0;
+
+ if (!commit->date)
+ return error_func(&commit->object, FSCK_ERROR, "invalid author/committer line");
+
+ if (memcmp(buffer, "tree ", 5))
+ return error_func(&commit->object, FSCK_ERROR, "invalid format - expected 'tree' line");
+ if (get_sha1_hex(buffer+5, tree_sha1) || buffer[45] != '\n')
+ return error_func(&commit->object, FSCK_ERROR, "invalid 'tree' line format - bad sha1");
+ buffer += 46;
+ while (!memcmp(buffer, "parent ", 7)) {
+ if (get_sha1_hex(buffer+7, sha1) || buffer[47] != '\n')
+ return error_func(&commit->object, FSCK_ERROR, "invalid 'parent' line format - bad sha1");
+ buffer += 48;
+ parents++;
+ }
+ graft = lookup_commit_graft(commit->object.sha1);
+ if (graft) {
+ struct commit_list *p = commit->parents;
+ parents = 0;
+ while (p) {
+ p = p->next;
+ parents++;
+ }
+ if (graft->nr_parent == -1 && !parents)
+ ; /* shallow commit */
+ else if (graft->nr_parent != parents)
+ return error_func(&commit->object, FSCK_ERROR, "graft objects missing");
+ } else {
+ struct commit_list *p = commit->parents;
+ while (p && parents) {
+ p = p->next;
+ parents--;
+ }
+ if (p || parents)
+ return error_func(&commit->object, FSCK_ERROR, "parent objects missing");
+ }
+ if (memcmp(buffer, "author ", 7))
+ return error_func(&commit->object, FSCK_ERROR, "invalid format - expected 'author' line");
+ if (!commit->tree)
+ return error_func(&commit->object, FSCK_ERROR, "could not load commit's tree %s", sha1_to_hex(tree_sha1));
+
+ return 0;
+}
+
+static int fsck_tag(struct tag *tag, fsck_error error_func)
+{
+ struct object *tagged = tag->tagged;
+
+ if (!tagged)
+ return error_func(&tag->object, FSCK_ERROR, "could not load tagged object");
+ return 0;
+}
+
+int fsck_object(struct object *obj, int strict, fsck_error error_func)
+{
+ if (!obj)
+ return error_func(obj, FSCK_ERROR, "no valid object to fsck");
+
+ if (obj->type == OBJ_BLOB)
+ return 0;
+ if (obj->type == OBJ_TREE)
+ return fsck_tree((struct tree *) obj, strict, error_func);
+ if (obj->type == OBJ_COMMIT)
+ return fsck_commit((struct commit *) obj, error_func);
+ if (obj->type == OBJ_TAG)
+ return fsck_tag((struct tag *) obj, error_func);
+
+ return error_func(obj, FSCK_ERROR, "unknown type '%d' (internal fsck error)",
+ obj->type);
+}
+
+int fsck_error_function(struct object *obj, int type, const char *fmt, ...)
+{
+ va_list ap;
+ int len;
+ struct strbuf sb = STRBUF_INIT;
+
+ strbuf_addf(&sb, "object %s:", obj->sha1?sha1_to_hex(obj->sha1):"(null)");
+
+ va_start(ap, fmt);
+ len = vsnprintf(sb.buf + sb.len, strbuf_avail(&sb), fmt, ap);
+ va_end(ap);
+
+ if (len < 0)
+ len = 0;
+ if (len >= strbuf_avail(&sb)) {
+ strbuf_grow(&sb, len + 2);
+ va_start(ap, fmt);
+ len = vsnprintf(sb.buf + sb.len, strbuf_avail(&sb), fmt, ap);
+ va_end(ap);
+ if (len >= strbuf_avail(&sb))
+ die("this should not happen, your snprintf is broken");
+ }
+
+ error("%s", sb.buf);
+ strbuf_release(&sb);
+ return 1;
+}