Change the magic number used to introduce a trie file, so that instead

[sgt/agedu] / trie.h

diff --git a/trie.h b/trie.h
index ef52a08..e27885f 100644 (file)
--- a/trie.h
+++ b/trie.h
@@ -50,11 +50,30 @@ int triebuild_finish(triebuild *tb);
 void triebuild_free(triebuild *tb);
 
 /* ----------------------------------------------------------------------
+ * Anomalous function which modifies a trie after it's memory-mapped.
+ */
+
+/*
+ * Invent new fake atimes for each directory in the trie, by
+ * taking the maximum (latest) of the directory's previously
+ * stored atime and the atimes of everything below it.
+ */
+void trie_fake_dir_atimes(void *t);
+
+/* ----------------------------------------------------------------------
  * Functions to query a trie given a pointer to the start of the
  * memory-mapped file.
  */
 
 /*
+ * Check the magic numbers at the start of the file. This should also
+ * verify that the file was built on a platform whose structure layout
+ * matches that of the agedu reading it. Returns nonzero on successful
+ * match, zero on mismatch.
+ */
+int trie_check_magic(const void *t);
+
+/*
  * Return the path separator character in use in the trie.
  */
 char trie_pathsep(const void *t);
@@ -80,6 +99,11 @@ unsigned long trie_before(const void *t, const char *pathname);
 void trie_getpath(const void *t, unsigned long n, char *buf);
 
 /*
+ * Return the trie_file * for the nth entry in the trie.
+ */
+const struct trie_file *trie_getfile(const void *t, unsigned long n);
+
+/*
  * Return the total number of entries in the whole trie.
  */
 unsigned long trie_count(const void *t);
@@ -99,6 +123,7 @@ unsigned long trie_count(const void *t);
 typedef struct triewalk triewalk;
 triewalk *triewalk_new(const void *t);
 const struct trie_file *triewalk_next(triewalk *tw, char *buf);
+void triewalk_rebase(triewalk *tw, const void *t);
 void triewalk_free(triewalk *tw);
 
 /* ----------------------------------------------------------------------