opkg: introduce the protype of active_list

     This can be used for upgrade path



git-svn-id: http://opkg.googlecode.com/svn/trunk@166 e8e0d7a0-c8d9-11dd-a880-a1081c7ac358

5 files changed, 526 insertions, 1 deletions

diff --git a/libopkg/Makefile.am b/libopkg/Makefile.am
index fbc2dd8..8783f15 100644
--- a/libopkg/Makefile.am
+++ b/libopkg/Makefile.am
@@ -24,7 +24,8 @@ opkg_list_sources = conffile.c conffile.h conffile_list.c conffile_list.h \
 		    nv_pair.c nv_pair.h nv_pair_list.c nv_pair_list.h \
 		    pkg_dest.c pkg_dest.h pkg_dest_list.c pkg_dest_list.h \
 		    pkg_src.c pkg_src.h pkg_src_list.c pkg_src_list.h \
-		    str_list.c str_list.h void_list.c void_list.h
+		    str_list.c str_list.h void_list.c void_list.h \
+		    active_list.c active.list.h list.h 
 opkg_util_sources = file_util.c file_util.h opkg_message.h opkg_message.c md5.c md5.h \
 		    sprintf_alloc.c sprintf_alloc.h str_util.c str_util.h \
 		    xregex.c xregex.h xsystem.c xsystem.h
diff --git a/libopkg/active_list.c b/libopkg/active_list.c
new file mode 100644
index 0000000..b4bbef9
--- /dev/null
+++ b/libopkg/active_list.c
@@ -0,0 +1,81 @@
+/* active_list.h - the opkg package management system
+
+   Tick Chen <tick@openmoko.com>
+
+   Copyright (C) 2008 Openmoko Inc. 
+
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2, or (at
+   your option) any later version.
+
+   This program is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+*/
+
+
+#include "active_list.h"
+#include <stdio.h>
+
+
+void active_list_init(struct active_list *ptr) {
+    INIT_LIST_HEAD(&ptr->node);
+    INIT_LIST_HEAD(&ptr->depend);
+    ptr->walked=0;
+    ptr->depended = NULL;
+}
+
+/**
+ */ 
+struct active_list * active_list_next(struct active_list *head, struct active_list *ptr) {
+    struct active_list *next=NULL;
+    if (!head || !ptr) {
+        fprintf(stderr, "active_list_prev head = %p, ptr = %p invalid value!!\n", head, ptr);
+        return NULL;
+    }
+    if (ptr == head) {
+        head->walked = !head->walked;
+        next = list_entry(ptr->node.next, struct active_list, node);
+        if (next == head)
+            return NULL;
+        return active_list_next(head, next);
+    }
+    if (ptr->depend.next != &ptr->depend) {
+        next = list_entry(ptr->depend.next, struct active_list, node);
+        if (head->walked != next->walked) {
+            ptr->walked = head->walked;
+            return active_list_next(head, next);
+        }
+    } 
+    if (ptr->walked != head->walked) {
+        ptr->walked = head->walked;
+        return ptr;
+    }
+
+    if (ptr->depended && ptr->node.next == &ptr->depended->depend ) {
+        return ptr->depended;
+    }
+
+    if (ptr->node.next != &head->node) {
+        next = list_entry(ptr->node.next, struct active_list, node);
+        return active_list_next(head, next);
+    } 
+    return NULL;
+}
+
+
+void active_list_clear(struct active_list *head) {
+}
+
+void active_list_add_depend(struct active_list *node, struct active_list *depend) {
+    list_del_init(&depend->node);
+    list_add_tail(&depend->node, &node->depend);
+    depend->depended  = node;
+}
+
+void active_list_add(struct active_list *head, struct active_list *node) {
+    list_del_init(&node->node);
+    list_add_tail(&node->node, &head->node);
+}
diff --git a/libopkg/active_list.h b/libopkg/active_list.h
new file mode 100644
index 0000000..6744234
--- /dev/null
+++ b/libopkg/active_list.h
@@ -0,0 +1,36 @@
+/* active_list.h - the opkg package management system
+
+   Tick Chen <tick@openmoko.com>
+
+   Copyright (C) 2008 Openmoko Inc. 
+
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2, or (at
+   your option) any later version.
+
+   This program is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+*/
+
+#ifndef ACTIVE_LIST_H
+#define ACTIVE_LIST_H
+
+#include "list.h"
+
+struct active_list {
+    struct list_head node;
+    struct list_head depend;
+    char walked;
+    struct active_list *depended;
+}  __attribute__((packed));
+
+struct active_list * active_list_next(struct active_list *head, struct active_list *ptr);
+void active_list_init(struct active_list *ptr);
+void active_list_clear(struct active_list *head);
+void active_list_add_depend(struct active_list *node, struct active_list *depend);
+void active_list_add(struct active_list *head, struct active_list *node);
+
+#endif
diff --git a/libopkg/list.h b/libopkg/list.h
new file mode 100644
index 0000000..0bd87b9
--- /dev/null
+++ b/libopkg/list.h
@@ -0,0 +1,304 @@
+/* list.h - the opkg package management system
+
+   Tick Chen <tick@openmoko.com>
+
+   Copyright (C) 2008 Openmoko Inc. 
+
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2, or (at
+   your option) any later version.
+
+   This program is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+
+   This is modified from Linux Kernel.
+*/
+
+#ifndef _LINUX_LIST_H
+#define _LINUX_LIST_H
+
+#define LIST_POISON1  ((void *) 0x00100100)
+#define LIST_POISON2  ((void *) 0x00200200)
+
+struct list_head {
+    struct list_head *next, *prev;
+};
+
+#define LIST_HEAD_INIT(name) { &(name), &(name) }
+
+#define LIST_HEAD(name) \
+	struct list_head name = LIST_HEAD_INIT(name)
+
+#define INIT_LIST_HEAD(ptr) do { \
+	(ptr)->next = (ptr); (ptr)->prev = (ptr); \
+} while (0)
+
+static inline void __list_add(struct list_head *new,
+                              struct list_head *prev,
+                              struct list_head *next) {
+    next->prev = new;
+    new->next = next;
+    new->prev = prev;
+    prev->next = new;
+}
+
+/**
+ * list_add - add a new entry
+ * @new: new entry to be added
+ * @head: list head to add it after
+ *
+ * Insert a new entry after the specified head.
+ * This is good for implementing stacks.
+ */
+static inline void list_add(struct list_head *new, struct list_head *head) {
+    __list_add(new, head, head->next);
+}
+
+/**
+ * list_add_tail - add a new entry
+ * @new: new entry to be added
+ * @head: list head to add it before
+ *
+ * Insert a new entry before the specified head.
+ * This is useful for implementing queues.
+ */
+static inline void list_add_tail(struct list_head *new, struct list_head *head) {
+    __list_add(new, head->prev, head);
+}
+
+
+/*
+ * Delete a list entry by making the prev/next entries
+ * point to each other.
+ *
+ * This is only for internal list manipulation where we know
+ * the prev/next entries already!
+ */
+static inline void __list_del(struct list_head * prev, struct list_head * next) {
+    next->prev = prev;
+    prev->next = next;
+}
+
+/**
+ * list_del - deletes entry from list.
+ * @entry: the element to delete from the list.
+ * Note: list_empty on entry does not return true after this, the entry is
+ * in an undefined state.
+ */
+static inline void list_del(struct list_head *entry) {
+    __list_del(entry->prev, entry->next);
+    entry->next = LIST_POISON1;
+    entry->prev = LIST_POISON2;
+}
+
+/**
+ * list_del_init - deletes entry from list and reinitialize it.
+ * @entry: the element to delete from the list.
+ */
+static inline void list_del_init(struct list_head *entry) {
+    __list_del(entry->prev, entry->next);
+    INIT_LIST_HEAD(entry);
+}
+
+/**
+ * list_move - delete from one list and add as another's head
+ * @list: the entry to move
+ * @head: the head that will precede our entry
+ */
+static inline void list_move(struct list_head *list, struct list_head *head) {
+    __list_del(list->prev, list->next);
+    list_add(list, head);
+}
+
+/**
+ * list_move_tail - delete from one list and add as another's tail
+ * @list: the entry to move
+ * @head: the head that will follow our entry
+ */
+static inline void list_move_tail(struct list_head *list,
+                                  struct list_head *head) {
+    __list_del(list->prev, list->next);
+    list_add_tail(list, head);
+}
+
+/**
+ * list_empty - tests whether a list is empty
+ * @head: the list to test.
+ */
+static inline int list_empty(const struct list_head *head) {
+    return head->next == head;
+}
+
+/**
+ * list_empty_careful - tests whether a list is
+ * empty _and_ checks that no other CPU might be
+ * in the process of still modifying either member
+ *
+ * NOTE: using list_empty_careful() without synchronization
+ * can only be safe if the only activity that can happen
+ * to the list entry is list_del_init(). Eg. it cannot be used
+ * if another CPU could re-list_add() it.
+ *
+ * @head: the list to test.
+ */
+static inline int list_empty_careful(const struct list_head *head) {
+    struct list_head *next = head->next;
+    return (next == head) && (next == head->prev);
+}
+
+static inline void __list_splice(struct list_head *list,
+                                 struct list_head *head) {
+    struct list_head *first = list->next;
+    struct list_head *last = list->prev;
+    struct list_head *at = head->next;
+
+    first->prev = head;
+    head->next = first;
+
+    last->next = at;
+    at->prev = last;
+}
+
+/**
+ * list_splice - join two lists
+ * @list: the new list to add.
+ * @head: the place to add it in the first list.
+ */
+static inline void list_splice(struct list_head *list, struct list_head *head) {
+    if (!list_empty(list))
+        __list_splice(list, head);
+}
+
+/**
+ * list_splice_init - join two lists and reinitialise the emptied list.
+ * @list: the new list to add.
+ * @head: the place to add it in the first list.
+ *
+ * The list at @list is reinitialised
+ */
+static inline void list_splice_init(struct list_head *list,
+                                    struct list_head *head) {
+    if (!list_empty(list)) {
+        __list_splice(list, head);
+        INIT_LIST_HEAD(list);
+    }
+}
+
+
+
+#define _offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
+#define container_of(ptr, type, member) ({                      \
+        const typeof( ((type *)0)->member ) *__mptr = (ptr);    \
+	(type *)( (char *)__mptr - _offsetof(type,member) );})
+
+/**
+ * list_entry - get the struct for this entry
+ * @ptr:	the &struct list_head pointer.
+ * @type:	the type of the struct this is embedded in.
+ * @member:	the name of the list_struct within the struct.
+ */
+#define list_entry(ptr, type, member) \
+	container_of(ptr, type, member)
+
+/**
+ * list_for_each	-	iterate over a list
+ * @pos:	the &struct list_head to use as a loop counter.
+ * @head:	the head for your list.
+ */
+#define list_for_each(pos, head) \
+	for (pos = (head)->next; pos != (head); \
+        	pos = pos->next)
+
+/**
+ * __list_for_each	-	iterate over a list
+ * @pos:	the &struct list_head to use as a loop counter.
+ * @head:	the head for your list.
+ *
+ * This variant differs from list_for_each() in that it's the
+ * simplest possible list iteration code, no prefetching is done.
+ * Use this for code that knows the list to be very short (empty
+ * or 1 entry) most of the time.
+ */
+#define __list_for_each(pos, head) \
+	for (pos = (head)->next; pos != (head); pos = pos->next)
+
+/**
+ * list_for_each_prev	-	iterate over a list backwards
+ * @pos:	the &struct list_head to use as a loop counter.
+ * @head:	the head for your list.
+ */
+#define list_for_each_prev(pos, head) \
+	for (pos = (head)->prev; pos != (head); \
+        	pos = pos->prev)
+
+/**
+ * list_for_each_safe	-	iterate over a list safe against removal of list entry
+ * @pos:	the &struct list_head to use as a loop counter.
+ * @n:		another &struct list_head to use as temporary storage
+ * @head:	the head for your list.
+ */
+#define list_for_each_safe(pos, n, head) \
+	for (pos = (head)->next, n = pos->next; pos != (head); \
+		pos = n, n = pos->next)
+
+/**
+ * list_for_each_entry	-	iterate over list of given type
+ * @pos:	the type * to use as a loop counter.
+ * @head:	the head for your list.
+ * @member:	the name of the list_struct within the struct.
+ */
+#define list_for_each_entry(pos, head, member)				\
+	for (pos = list_entry((head)->next, typeof(*pos), member);	\
+	     &pos->member != (head); 	\
+	     pos = list_entry(pos->member.next, typeof(*pos), member))
+
+/**
+ * list_for_each_entry_reverse - iterate backwards over list of given type.
+ * @pos:	the type * to use as a loop counter.
+ * @head:	the head for your list.
+ * @member:	the name of the list_struct within the struct.
+ */
+#define list_for_each_entry_reverse(pos, head, member)			\
+	for (pos = list_entry((head)->prev, typeof(*pos), member);	\
+	     &pos->member != (head); 	\
+	     pos = list_entry(pos->member.prev, typeof(*pos), member))
+
+/**
+ * list_prepare_entry - prepare a pos entry for use as a start point in
+ *			list_for_each_entry_continue
+ * @pos:	the type * to use as a start point
+ * @head:	the head of the list
+ * @member:	the name of the list_struct within the struct.
+ */
+#define list_prepare_entry(pos, head, member) \
+	((pos) ? : list_entry(head, typeof(*pos), member))
+
+/**
+ * list_for_each_entry_continue -	iterate over list of given type
+ *			continuing after existing point
+ * @pos:	the type * to use as a loop counter.
+ * @head:	the head for your list.
+ * @member:	the name of the list_struct within the struct.
+ */
+#define list_for_each_entry_continue(pos, head, member) 		\
+	for (pos = list_entry(pos->member.next, typeof(*pos), member);	\
+	     &pos->member != (head);	\
+	     pos = list_entry(pos->member.next, typeof(*pos), member))
+
+/**
+ * list_for_each_entry_safe - iterate over list of given type safe against removal of list entry
+ * @pos:	the type * to use as a loop counter.
+ * @n:		another type * to use as temporary storage
+ * @head:	the head for your list.
+ * @member:	the name of the list_struct within the struct.
+ */
+#define list_for_each_entry_safe(pos, n, head, member)			\
+	for (pos = list_entry((head)->next, typeof(*pos), member),	\
+		n = list_entry(pos->member.next, typeof(*pos), member);	\
+	     &pos->member != (head); 					\
+	     pos = n, n = list_entry(n->member.next, typeof(*n), member))
+
+#endif
diff --git a/tests/opkg_active_list_test.c b/tests/opkg_active_list_test.c
new file mode 100644
index 0000000..ec6bec1
--- /dev/null
+++ b/tests/opkg_active_list_test.c
@@ -0,0 +1,103 @@
+
+/*
+．--A---B----C----D-----E----F
+    |             |__k---L
+    |                    |_ N
+    |__ G ---H ---I---J
+             |_M      |_O
+
+Then the sequence will be 
+G M H I O J A B K N L C D E F
+*/
+
+#include <stdlib.h>
+#include <libopkg/active_list.h>
+#include <stdio.h>
+
+struct active_test {
+    char *str;
+    struct active_list list;
+} __attribute__((packed));
+
+struct active_test *active_test_new(char *str) {
+    struct active_test *ans = (struct active_test *)calloc(1, sizeof(struct active_test));
+    ans->str = str;
+    active_list_init(&ans->list); 
+    return ans;
+}
+void active_test_add(struct active_list *head, struct active_test *node) {
+    active_list_add(head, &node->list);
+}
+
+void active_test_add_depend(struct active_test *A, struct active_test *B) {
+    active_list_add_depend(&A->list, &B->list);
+}
+
+void make_list(struct active_list *head) {
+    struct active_test *A = active_test_new("A");
+    struct active_test *B = active_test_new("B");
+    struct active_test *C = active_test_new("C");
+    struct active_test *D = active_test_new("D");
+    struct active_test *E = active_test_new("E");
+    struct active_test *F = active_test_new("F");
+    struct active_test *G = active_test_new("G");
+    struct active_test *H = active_test_new("H");
+    struct active_test *I = active_test_new("I");
+    struct active_test *J = active_test_new("J");
+    struct active_test *K = active_test_new("K");
+    struct active_test *L = active_test_new("L");
+    struct active_test *M = active_test_new("M");
+    struct active_test *N = active_test_new("N");
+    struct active_test *O = active_test_new("O");
+
+    active_test_add(head, A);
+    active_test_add(head, B);
+    active_test_add(head, C);
+    active_test_add(head, D);
+    active_test_add(head, E);
+    active_test_add(head, F);
+    active_test_add(head, G);
+    active_test_add(head, H);
+    active_test_add(head, I);
+    active_test_add(head, J);
+    active_test_add(head, K);
+    active_test_add(head, L);
+    active_test_add(head, M);
+    active_test_add(head, N);
+    active_test_add(head, O);
+    active_test_add_depend(H, M);
+    active_test_add_depend(A, G);
+    active_test_add_depend(A, H);
+    active_test_add_depend(A, I);
+    active_test_add_depend(A, J);
+    active_test_add_depend(J, O);
+    active_test_add_depend(C, K);
+    active_test_add_depend(C, L); 
+    active_test_add_depend(L, N);
+}
+
+int main (void) {
+    struct active_list head;
+    struct active_list *ptr;
+    struct active_test *test;
+    active_list_init(&head);
+    make_list(&head);
+
+    for(ptr = active_list_next(&head, &head); ptr ;ptr = active_list_next(&head, ptr)) {
+        test = list_entry(ptr, struct active_test, list);
+        printf ("%s ",test->str);
+    }
+    printf("\n");
+    for(ptr = active_list_next(&head, &head); ptr ;ptr = active_list_next(&head, ptr)) {
+        test = list_entry(ptr, struct active_test, list);
+        printf ("%s ",test->str);
+    }
+    printf("\n");
+    for(ptr = active_list_next(&head, &head); ptr ;ptr = active_list_next(&head, ptr)) {
+        test = list_entry(ptr, struct active_test, list);
+        printf ("%s ",test->str);
+    }
+    printf("\n");
+
+
+}