Make history functions generic

Signed-off-by: Lon Hohberger <lhh@redhat.com>

include/history.h

@@ -0,0 +1,25 @@
+#ifndef _HISTORY_H
+#define _HISTORY_H
+
+typedef struct _history_node {
+	list_head();
+	void *data;
+	time_t when;
+} history_node;
+
+typedef int (*history_compare_fn)(void *, void *);
+
+typedef struct _history_info {
+	history_node *hist;
+	history_compare_fn compare_func;
+	time_t timeout;
+	size_t element_size;
+} history_info_t;
+
+history_info_t *history_init(history_compare_fn func,
+			     time_t expiration, size_t element_size);
+int history_check(history_info_t *hinfo, void *stuff);
+int history_record(history_info_t *hinfo, void *data);
+int history_wipe(history_info_t *hinfo);
+
+#endif

server/history.c

@@ -0,0 +1,122 @@
+#include <stdio.h>
+#include <malloc.h>
+#include <sys/types.h>
+#include <errno.h>
+#include <string.h>
+#include <list.h>
+#include <history.h>
+#include <time.h>
+
+
+history_info_t *
+history_init(history_compare_fn func, time_t expiration, size_t element_size)
+{
+	history_info_t *hist;
+
+	errno = EINVAL;
+	if (!func || !expiration || !element_size)
+		return NULL;
+
+	hist = malloc(sizeof(*hist));
+	if (!hist)
+		return NULL;
+	memset(hist, 0, sizeof(*hist));
+
+	hist->timeout = expiration;
+	hist->element_size = element_size;
+	hist->compare_func = func;
+
+	return hist;
+}
+
+
+/*
+ * Purge our history when the entries time out.
+ *
+ * Returns 1 if a matching history node was found, or 0
+ * if not. 
+ */
+int
+history_check(history_info_t *hinfo, void *stuff)
+{
+	history_node *entry = NULL;
+	time_t now;
+	int x;
+
+	if (!hinfo)
+		return 0; /* XXX */
+
+	if (!hinfo->hist)
+		return 0;
+
+	now = time(NULL);
+
+loop_again:
+	list_for((&hinfo->hist), entry, x) {
+		if (entry->when < (now - hinfo->timeout)) {
+			list_remove((&hinfo->hist), entry);
+			free(entry->data);
+			free(entry);
+			goto loop_again;
+		}
+
+		if (hinfo->compare_func(entry->data, stuff)) {
+			return 1;
+		}
+	}
+	return 0;
+}
+
+
+int
+history_record(history_info_t *hinfo, void *data)
+{
+	history_node *entry = NULL;
+
+	errno = EINVAL;
+	if (!data || !hinfo)
+		return -1;
+
+	if (history_check(hinfo, data) == 1) {
+		errno = EEXIST;
+		return -1;
+	}
+
+	entry = malloc(sizeof(*entry));
+	if (!entry) {
+		return -1;
+	}
+	memset(entry, 0, sizeof(*entry));
+
+	entry->data = malloc(hinfo->element_size);
+	if (!entry->data) {
+		free(entry);
+		errno = ENOMEM;
+		return -1;
+	}
+
+	memcpy(entry->data, data, hinfo->element_size);
+	entry->when = time(NULL);
+	list_insert((&hinfo->hist), entry);
+	return 0;
+}
+
+
+int
+history_wipe(history_info_t *hinfo)
+{
+	history_node *entry = NULL;
+
+	if (!hinfo)
+		return -1;
+
+	while (hinfo->hist) {
+		entry = hinfo->hist;
+		list_remove((&hinfo->hist), entry);
+		free(entry->data);
+		free(entry);
+	}
+
+	/* User must free(hinfo); */
+	return 0;
+}