X-Git-Url: http://git.tuebingen.mpg.de/?p=adu.git;a=blobdiff_plain;f=user.c;h=026d65be741fdc3a100c24f6cce379f8eaa124e0;hp=8959c847b0b2069c76965850fc2acc07a8cfa097;hb=ca20c17a6742464bcf861fe856a4caddf2bfeab2;hpb=3bb9b0ca535be1eb28b64972bdf0e205e6afc93e

diff --git a/user.c b/user.c
index 8959c84..026d65b 100644
--- a/user.c
+++ b/user.c
@@ -52,9 +52,6 @@ static struct user_info *uid_hash_table;
 /** This is always a power of two. It is set in create_hash_table(). */
 static uint32_t uid_hash_table_size;
 
-/* Array of indices to the entries of \a uid_hash_table. */
-static int *uid_hash_table_sort_idx;
-
 /** The number of used slots in the hash table. */
 static uint32_t num_uids;
 
@@ -325,8 +322,7 @@ int for_each_admissible_user(int (*func)(struct user_info *, void *),
 	assert(uid_hash_table);
 	for (i = 0; i < uid_hash_table_size; i++) {
 		int ret;
-		struct user_info *ui = uid_hash_table +
-			uid_hash_table_sort_idx[i];
+		struct user_info *ui = uid_hash_table + i;
 
 		if (!ui_used(ui) || !ui_admissible(ui))
 			continue;
@@ -337,21 +333,29 @@ int for_each_admissible_user(int (*func)(struct user_info *, void *),
 	return 1;
 }
 
+/** Prime number used for calculating the slot for an uid. */
 #define PRIME1 0xb11924e1
+/** Prime number used for probe all slots. */
 #define PRIME2 0x01000193
 
+/**
+ * Create a hash table large enough of given size.
+ *
+ * \param bits Sets the maximal number of hash table entries to ^bits.
+ */
 void create_hash_table(unsigned bits)
 {
-	int i;
-
 	uid_hash_table_size = 1 << bits;
 	uid_hash_table = adu_calloc(uid_hash_table_size *
 		sizeof(struct user_info));
-	uid_hash_table_sort_idx = adu_malloc(uid_hash_table_size * sizeof(int));
-	for (i = 0; i < uid_hash_table_size; i++)
-		uid_hash_table_sort_idx[i] = i;
 }
 
+/**
+ * Close all open user tables and destroy the uid hash table.
+ *
+ * For each used slot in the uid hash table, close the osl user table if it is
+ * open.  Finally, free the uid hash table.
+ */
 void close_user_tables(void)
 {
 	struct user_info *ui;
@@ -381,8 +385,6 @@ void close_user_tables(void)
 	}
 	free(uid_hash_table);
 	uid_hash_table = NULL;
-	free(uid_hash_table_sort_idx);
-	uid_hash_table_sort_idx = NULL;
 }
 
 /*
@@ -421,6 +423,19 @@ static struct user_info *lookup_uid(uint32_t uid)
 	return NULL;
 }
 
+/**
+ * Create and open a osl table for the given uid.
+ *
+ * \param uid The user ID.
+ * \param ui_ptr Result pointer
+ *
+ * Find out whether \a uid already exists in the uid hash table.  If yes, just
+ * return the user info struct via \a ui_ptr. Otherwise, insert \a uid into the
+ * uid hash table, create and open the osl user table and also return the user
+ * info struct via \a ui_ptr.
+ *
+ * \return Standard.
+ */
 int create_user_table(uint32_t uid, struct user_info **ui_ptr)
 {
 	struct user_info *ui = lookup_uid(uid);
@@ -439,23 +454,21 @@ static char *get_uid_list_name(void)
 {
 	return make_message("%s/uid_list", conf.database_dir_arg);
 }
-
-static int (*hash_table_comparator)(struct user_info *a, struct user_info *b);
-
-static int comp_wrapper(const void *a, const void *b)
-{
-	struct user_info *x = uid_hash_table + *(unsigned *)a;
-	struct user_info *y = uid_hash_table + *(unsigned *)b;
-	return hash_table_comparator(x, y);
-}
-
-void sort_hash_table(int (*comp)(struct user_info *, struct user_info *))
-{
-	hash_table_comparator = comp;
-	qsort(uid_hash_table_sort_idx, uid_hash_table_size,
-		sizeof(*uid_hash_table_sort_idx), comp_wrapper);
-}
-
+/**
+ * Open the osl tables for all admissible uids.
+ *
+ * \param admissible_uids Determines which uids are considered admissible.
+ *
+ * Each slot in the hash table contains, among other information, a bit which
+ * specifies whether the uid of the slot is admissible in the current context.
+ *
+ * This function iterates over all entries in the hash table and checks for
+ * each used slot whether the corresponding uid is admissible with respect to
+ * \a admissible_uids. If so, it sets the admissible bit for this slot and
+ * opens the osl table of the uid.
+ *
+ * \return Stamdard.
+ */
 int open_admissible_user_tables(struct uid_range *admissible_uids)
 {
 	struct user_info *ui;
@@ -482,6 +495,18 @@ int open_admissible_user_tables(struct uid_range *admissible_uids)
 	return 1;
 }
 
+/**
+ * Read the file of all possible uids.
+ *
+ * This is called from select/interactive mode. First a large hash table, large
+ * enough to store all uids contained in the uid file is created. Next, the
+ * uids are read from the uid file which was created during the creation of the
+ * database and each uid is inserted into the hash table.
+ *
+ * \sa write_uid_file().
+ *
+ * \return Standard.
+ */
 int read_uid_file(void)
 {
 	size_t size;
@@ -524,6 +549,18 @@ out:
 	return ret;
 }
 
+/**
+ * Write the list of uids to permanent storage.
+ *
+ * This is called from create mode after the dir table and all uer tables have
+ * been created. The file simply contains the list of all uids that own at
+ * least one regular file in the base directory and hence an osl table for this
+ * uid exists.
+ *
+ * \sa read_uid_file().
+ *
+ * \return Standard.
+ */
 int write_uid_file(void)
 {
 	char *buf, *p, *filename;