Add a new list API from CCAN. Signed-off-by: Valentina Manea <valentina.manea.m@xxxxxxxxx> --- drivers/staging/usbip/userspace/libsrc/Makefile.am | 3 +- .../staging/usbip/userspace/libsrc/build_assert.h | 40 ++ .../staging/usbip/userspace/libsrc/check_type.h | 64 +++ .../staging/usbip/userspace/libsrc/container_of.h | 109 ++++ drivers/staging/usbip/userspace/libsrc/list.c | 43 ++ drivers/staging/usbip/userspace/libsrc/list.h | 613 +++++++++++++++++++++ 6 files changed, 871 insertions(+), 1 deletion(-) create mode 100644 drivers/staging/usbip/userspace/libsrc/build_assert.h create mode 100644 drivers/staging/usbip/userspace/libsrc/check_type.h create mode 100644 drivers/staging/usbip/userspace/libsrc/container_of.h create mode 100644 drivers/staging/usbip/userspace/libsrc/list.c create mode 100644 drivers/staging/usbip/userspace/libsrc/list.h diff --git a/drivers/staging/usbip/userspace/libsrc/Makefile.am b/drivers/staging/usbip/userspace/libsrc/Makefile.am index 4921189..294270b 100644 --- a/drivers/staging/usbip/userspace/libsrc/Makefile.am +++ b/drivers/staging/usbip/userspace/libsrc/Makefile.am @@ -4,4 +4,5 @@ libusbip_la_LDFLAGS = -version-info @LIBUSBIP_VERSION@ lib_LTLIBRARIES := libusbip.la libusbip_la_SOURCES := names.c names.h usbip_host_driver.c usbip_host_driver.h \ - usbip_common.c usbip_common.h vhci_driver.c vhci_driver.h + usbip_common.c usbip_common.h vhci_driver.c vhci_driver.h \ + list.c list.h build_assert.h check_type.h container_of.h diff --git a/drivers/staging/usbip/userspace/libsrc/build_assert.h b/drivers/staging/usbip/userspace/libsrc/build_assert.h new file mode 100644 index 0000000..b9ecd84 --- /dev/null +++ b/drivers/staging/usbip/userspace/libsrc/build_assert.h @@ -0,0 +1,40 @@ +/* CC0 (Public domain) - see LICENSE file for details */ +#ifndef CCAN_BUILD_ASSERT_H +#define CCAN_BUILD_ASSERT_H + +/** + * BUILD_ASSERT - assert a build-time dependency. + * @cond: the compile-time condition which must be true. + * + * Your compile will fail if the condition isn't true, or can't be evaluated + * by the compiler. This can only be used within a function. + * + * Example: + * #include <stddef.h> + * ... + * static char *foo_to_char(struct foo *foo) + * { + * // This code needs string to be at start of foo. + * BUILD_ASSERT(offsetof(struct foo, string) == 0); + * return (char *)foo; + * } + */ +#define BUILD_ASSERT(cond) \ + do { (void) sizeof(char [1 - 2*!(cond)]); } while(0) + +/** + * BUILD_ASSERT_OR_ZERO - assert a build-time dependency, as an expression. + * @cond: the compile-time condition which must be true. + * + * Your compile will fail if the condition isn't true, or can't be evaluated + * by the compiler. This can be used in an expression: its value is "0". + * + * Example: + * #define foo_to_char(foo) \ + * ((char *)(foo) \ + * + BUILD_ASSERT_OR_ZERO(offsetof(struct foo, string) == 0)) + */ +#define BUILD_ASSERT_OR_ZERO(cond) \ + (sizeof(char [1 - 2*!(cond)]) - 1) + +#endif /* CCAN_BUILD_ASSERT_H */ diff --git a/drivers/staging/usbip/userspace/libsrc/check_type.h b/drivers/staging/usbip/userspace/libsrc/check_type.h new file mode 100644 index 0000000..a39cc41 --- /dev/null +++ b/drivers/staging/usbip/userspace/libsrc/check_type.h @@ -0,0 +1,64 @@ +/* CC0 (Public domain) - see LICENSE file for details */ +#ifndef CCAN_CHECK_TYPE_H +#define CCAN_CHECK_TYPE_H +#include "config.h" + +/** + * check_type - issue a warning or build failure if type is not correct. + * @expr: the expression whose type we should check (not evaluated). + * @type: the exact type we expect the expression to be. + * + * This macro is usually used within other macros to try to ensure that a macro + * argument is of the expected type. No type promotion of the expression is + * done: an unsigned int is not the same as an int! + * + * check_type() always evaluates to 0. + * + * If your compiler does not support typeof, then the best we can do is fail + * to compile if the sizes of the types are unequal (a less complete check). + * + * Example: + * // They should always pass a 64-bit value to _set_some_value! + * #define set_some_value(expr) \ + * _set_some_value((check_type((expr), uint64_t), (expr))) + */ + +/** + * check_types_match - issue a warning or build failure if types are not same. + * @expr1: the first expression (not evaluated). + * @expr2: the second expression (not evaluated). + * + * This macro is usually used within other macros to try to ensure that + * arguments are of identical types. No type promotion of the expressions is + * done: an unsigned int is not the same as an int! + * + * check_types_match() always evaluates to 0. + * + * If your compiler does not support typeof, then the best we can do is fail + * to compile if the sizes of the types are unequal (a less complete check). + * + * Example: + * // Do subtraction to get to enclosing type, but make sure that + * // pointer is of correct type for that member. + * #define container_of(mbr_ptr, encl_type, mbr) \ + * (check_types_match((mbr_ptr), &((encl_type *)0)->mbr), \ + * ((encl_type *) \ + * ((char *)(mbr_ptr) - offsetof(enclosing_type, mbr)))) + */ +#if HAVE_TYPEOF +#define check_type(expr, type) \ + ((typeof(expr) *)0 != (type *)0) + +#define check_types_match(expr1, expr2) \ + ((typeof(expr1) *)0 != (typeof(expr2) *)0) +#else +#include <build_assert.h> +/* Without typeof, we can only test the sizes. */ +#define check_type(expr, type) \ + BUILD_ASSERT_OR_ZERO(sizeof(expr) == sizeof(type)) + +#define check_types_match(expr1, expr2) \ + BUILD_ASSERT_OR_ZERO(sizeof(expr1) == sizeof(expr2)) +#endif /* HAVE_TYPEOF */ + +#endif /* CCAN_CHECK_TYPE_H */ diff --git a/drivers/staging/usbip/userspace/libsrc/container_of.h b/drivers/staging/usbip/userspace/libsrc/container_of.h new file mode 100644 index 0000000..4afd0fe --- /dev/null +++ b/drivers/staging/usbip/userspace/libsrc/container_of.h @@ -0,0 +1,109 @@ +/* CC0 (Public domain) - see LICENSE file for details */ +#ifndef CCAN_CONTAINER_OF_H +#define CCAN_CONTAINER_OF_H +#include <stddef.h> + +#include "config.h" +#include <check_type.h> + +/** + * container_of - get pointer to enclosing structure + * @member_ptr: pointer to the structure member + * @containing_type: the type this member is within + * @member: the name of this member within the structure. + * + * Given a pointer to a member of a structure, this macro does pointer + * subtraction to return the pointer to the enclosing type. + * + * Example: + * struct foo { + * int fielda, fieldb; + * // ... + * }; + * struct info { + * int some_other_field; + * struct foo my_foo; + * }; + * + * static struct info *foo_to_info(struct foo *foo) + * { + * return container_of(foo, struct info, my_foo); + * } + */ +#define container_of(member_ptr, containing_type, member) \ + ((containing_type *) \ + ((char *)(member_ptr) \ + - container_off(containing_type, member)) \ + + check_types_match(*(member_ptr), ((containing_type *)0)->member)) + +/** + * container_off - get offset to enclosing structure + * @containing_type: the type this member is within + * @member: the name of this member within the structure. + * + * Given a pointer to a member of a structure, this macro does + * typechecking and figures out the offset to the enclosing type. + * + * Example: + * struct foo { + * int fielda, fieldb; + * // ... + * }; + * struct info { + * int some_other_field; + * struct foo my_foo; + * }; + * + * static struct info *foo_to_info(struct foo *foo) + * { + * size_t off = container_off(struct info, my_foo); + * return (void *)((char *)foo - off); + * } + */ +#define container_off(containing_type, member) \ + offsetof(containing_type, member) + +/** + * container_of_var - get pointer to enclosing structure using a variable + * @member_ptr: pointer to the structure member + * @container_var: a pointer of same type as this member's container + * @member: the name of this member within the structure. + * + * Given a pointer to a member of a structure, this macro does pointer + * subtraction to return the pointer to the enclosing type. + * + * Example: + * static struct info *foo_to_i(struct foo *foo) + * { + * struct info *i = container_of_var(foo, i, my_foo); + * return i; + * } + */ +#if HAVE_TYPEOF +#define container_of_var(member_ptr, container_var, member) \ + container_of(member_ptr, typeof(*container_var), member) +#else +#define container_of_var(member_ptr, container_var, member) \ + ((void *)((char *)(member_ptr) - \ + container_off_var(container_var, member))) +#endif + +/** + * container_off_var - get offset of a field in enclosing structure + * @container_var: a pointer to a container structure + * @member: the name of a member within the structure. + * + * Given (any) pointer to a structure and a its member name, this + * macro does pointer subtraction to return offset of member in a + * structure memory layout. + * + */ +#if HAVE_TYPEOF +#define container_off_var(var, member) \ + container_off(typeof(*var), member) +#else +#define container_off_var(var, member) \ + ((char *)&(var)->member - (char *)(var)) +#endif + +#endif /* CCAN_CONTAINER_OF_H */ diff --git a/drivers/staging/usbip/userspace/libsrc/list.c b/drivers/staging/usbip/userspace/libsrc/list.c new file mode 100644 index 0000000..2717fa3 --- /dev/null +++ b/drivers/staging/usbip/userspace/libsrc/list.c @@ -0,0 +1,43 @@ +/* Licensed under BSD-MIT - see LICENSE file for details */ +#include <stdio.h> +#include <stdlib.h> +#include "list.h" + +static void *corrupt(const char *abortstr, + const struct list_node *head, + const struct list_node *node, + unsigned int count) +{ + if (abortstr) { + fprintf(stderr, + "%s: prev corrupt in node %p (%u) of %p\n", + abortstr, node, count, head); + abort(); + } + return NULL; +} + +struct list_node *list_check_node(const struct list_node *node, + const char *abortstr) +{ + const struct list_node *p, *n; + int count = 0; + + for (p = node, n = node->next; n != node; p = n, n = n->next) { + count++; + if (n->prev != p) + return corrupt(abortstr, node, n, count); + } + /* Check prev on head node. */ + if (node->prev != p) + return corrupt(abortstr, node, node, 0); + + return (struct list_node *)node; +} + +struct list_head *list_check(const struct list_head *h, const char *abortstr) +{ + if (!list_check_node(&h->n, abortstr)) + return NULL; + return (struct list_head *)h; +} diff --git a/drivers/staging/usbip/userspace/libsrc/list.h b/drivers/staging/usbip/userspace/libsrc/list.h new file mode 100644 index 0000000..dadb40a --- /dev/null +++ b/drivers/staging/usbip/userspace/libsrc/list.h @@ -0,0 +1,613 @@ +/* Licensed under BSD-MIT - see LICENSE file for details */ +#ifndef CCAN_LIST_H +#define CCAN_LIST_H +#include <stdbool.h> +#include <assert.h> +#include <container_of.h> +#include <check_type.h> + +/** + * struct list_node - an entry in a doubly-linked list + * @next: next entry (self if empty) + * @prev: previous entry (self if empty) + * + * This is used as an entry in a linked list. + * Example: + * struct child { + * const char *name; + * // Linked list of all us children. + * struct list_node list; + * }; + */ +struct list_node { + struct list_node *next, *prev; +}; + +/** + * struct list_head - the head of a doubly-linked list + * @h: the list_head (containing next and prev pointers) + * + * This is used as the head of a linked list. + * Example: + * struct parent { + * const char *name; + * struct list_head children; + * unsigned int num_children; + * }; + */ +struct list_head { + struct list_node n; +}; + +/** + * list_check - check head of a list for consistency + * @h: the list_head + * @abortstr: the location to print on aborting, or NULL. + * + * Because list_nodes have redundant information, consistency checking between + * the back and forward links can be done. This is useful as a debugging check. + * If @abortstr is non-NULL, that will be printed in a diagnostic if the list + * is inconsistent, and the function will abort. + * + * Returns the list head if the list is consistent, NULL if not (it + * can never return NULL if @abortstr is set). + * + * See also: list_check_node() + * + * Example: + * static void dump_parent(struct parent *p) + * { + * struct child *c; + * + * printf("%s (%u children):\n", p->name, p->num_children); + * list_check(&p->children, "bad child list"); + * list_for_each(&p->children, c, list) + * printf(" -> %s\n", c->name); + * } + */ +struct list_head *list_check(const struct list_head *h, const char *abortstr); + +/** + * list_check_node - check node of a list for consistency + * @n: the list_node + * @abortstr: the location to print on aborting, or NULL. + * + * Check consistency of the list node is in (it must be in one). + * + * See also: list_check() + * + * Example: + * static void dump_child(const struct child *c) + * { + * list_check_node(&c->list, "bad child list"); + * printf("%s\n", c->name); + * } + */ +struct list_node *list_check_node(const struct list_node *n, + const char *abortstr); + +#ifdef CCAN_LIST_DEBUG +#define list_debug(h) list_check((h), __func__) +#define list_debug_node(n) list_check_node((n), __func__) +#else +#define list_debug(h) (h) +#define list_debug_node(n) (n) +#endif + +/** + * LIST_HEAD_INIT - initializer for an empty list_head + * @name: the name of the list. + * + * Explicit initializer for an empty list. + * + * See also: + * LIST_HEAD, list_head_init() + * + * Example: + * static struct list_head my_list = LIST_HEAD_INIT(my_list); + */ +#define LIST_HEAD_INIT(name) { { &name.n, &name.n } } + +/** + * LIST_HEAD - define and initialize an empty list_head + * @name: the name of the list. + * + * The LIST_HEAD macro defines a list_head and initializes it to an empty + * list. It can be prepended by "static" to define a static list_head. + * + * See also: + * LIST_HEAD_INIT, list_head_init() + * + * Example: + * static LIST_HEAD(my_global_list); + */ +#define LIST_HEAD(name) \ + struct list_head name = LIST_HEAD_INIT(name) + +/** + * list_head_init - initialize a list_head + * @h: the list_head to set to the empty list + * + * Example: + * ... + * struct parent *parent = malloc(sizeof(*parent)); + * + * list_head_init(&parent->children); + * parent->num_children = 0; + */ +static inline void list_head_init(struct list_head *h) +{ + h->n.next = h->n.prev = &h->n; +} + +/** + * list_add - add an entry at the start of a linked list. + * @h: the list_head to add the node to + * @n: the list_node to add to the list. + * + * The list_node does not need to be initialized; it will be overwritten. + * Example: + * struct child *child = malloc(sizeof(*child)); + * + * child->name = "marvin"; + * list_add(&parent->children, &child->list); + * parent->num_children++; + */ +static inline void list_add(struct list_head *h, struct list_node *n) +{ + n->next = h->n.next; + n->prev = &h->n; + h->n.next->prev = n; + h->n.next = n; + (void)list_debug(h); +} + +/** + * list_add_tail - add an entry at the end of a linked list. + * @h: the list_head to add the node to + * @n: the list_node to add to the list. + * + * The list_node does not need to be initialized; it will be overwritten. + * Example: + * list_add_tail(&parent->children, &child->list); + * parent->num_children++; + */ +static inline void list_add_tail(struct list_head *h, struct list_node *n) +{ + n->next = &h->n; + n->prev = h->n.prev; + h->n.prev->next = n; + h->n.prev = n; + (void)list_debug(h); +} + +/** + * list_empty - is a list empty? + * @h: the list_head + * + * If the list is empty, returns true. + * + * Example: + * assert(list_empty(&parent->children) == (parent->num_children == 0)); + */ +static inline bool list_empty(const struct list_head *h) +{ + (void)list_debug(h); + return h->n.next == &h->n; +} + +/** + * list_del - delete an entry from an (unknown) linked list. + * @n: the list_node to delete from the list. + * + * Note that this leaves @n in an undefined state; it can be added to + * another list, but not deleted again. + * + * See also: + * list_del_from() + * + * Example: + * list_del(&child->list); + * parent->num_children--; + */ +static inline void list_del(struct list_node *n) +{ + (void)list_debug_node(n); + n->next->prev = n->prev; + n->prev->next = n->next; +#ifdef CCAN_LIST_DEBUG + /* Catch use-after-del. */ + n->next = n->prev = NULL; +#endif +} + +/** + * list_del_from - delete an entry from a known linked list. + * @h: the list_head the node is in. + * @n: the list_node to delete from the list. + * + * This explicitly indicates which list a node is expected to be in, + * which is better documentation and can catch more bugs. + * + * See also: list_del() + * + * Example: + * list_del_from(&parent->children, &child->list); + * parent->num_children--; + */ +static inline void list_del_from(struct list_head *h, struct list_node *n) +{ +#ifdef CCAN_LIST_DEBUG + { + /* Thorough check: make sure it was in list! */ + struct list_node *i; + for (i = h->n.next; i != n; i = i->next) + assert(i != &h->n); + } +#endif /* CCAN_LIST_DEBUG */ + + /* Quick test that catches a surprising number of bugs. */ + assert(!list_empty(h)); + list_del(n); +} + +/** + * list_entry - convert a list_node back into the structure containing it. + * @n: the list_node + * @type: the type of the entry + * @member: the list_node member of the type + * + * Example: + * // First list entry is children.next; convert back to child. + * child = list_entry(parent->children.n.next, struct child, list); + * + * See Also: + * list_top(), list_for_each() + */ +#define list_entry(n, type, member) container_of(n, type, member) + +/** + * list_top - get the first entry in a list + * @h: the list_head + * @type: the type of the entry + * @member: the list_node member of the type + * + * If the list is empty, returns NULL. + * + * Example: + * struct child *first; + * first = list_top(&parent->children, struct child, list); + * if (!first) + * printf("Empty list!\n"); + */ +#define list_top(h, type, member) \ + ((type *)list_top_((h), list_off_(type, member))) + +static inline const void *list_top_(const struct list_head *h, size_t off) +{ + if (list_empty(h)) + return NULL; + return (const char *)h->n.next - off; +} + +/** + * list_pop - remove the first entry in a list + * @h: the list_head + * @type: the type of the entry + * @member: the list_node member of the type + * + * If the list is empty, returns NULL. + * + * Example: + * struct child *one; + * one = list_pop(&parent->children, struct child, list); + * if (!one) + * printf("Empty list!\n"); + */ +#define list_pop(h, type, member) \ + ((type *)list_pop_((h), list_off_(type, member))) + +static inline const void *list_pop_(const struct list_head *h, size_t off) +{ + struct list_node *n; + + if (list_empty(h)) + return NULL; + n = h->n.next; + list_del(n); + return (const char *)n - off; +} + +/** + * list_tail - get the last entry in a list + * @h: the list_head + * @type: the type of the entry + * @member: the list_node member of the type + * + * If the list is empty, returns NULL. + * + * Example: + * struct child *last; + * last = list_tail(&parent->children, struct child, list); + * if (!last) + * printf("Empty list!\n"); + */ +#define list_tail(h, type, member) \ + ((type *)list_tail_((h), list_off_(type, member))) + +static inline const void *list_tail_(const struct list_head *h, size_t off) +{ + if (list_empty(h)) + return NULL; + return (const char *)h->n.prev - off; +} + +/** + * list_for_each - iterate through a list. + * @h: the list_head (warning: evaluated multiple times!) + * @i: the structure containing the list_node + * @member: the list_node member of the structure + * + * This is a convenient wrapper to iterate @i over the entire list. It's + * a for loop, so you can break and continue as normal. + * + * Example: + * list_for_each(&parent->children, child, list) + * printf("Name: %s\n", child->name); + */ +#define list_for_each(h, i, member) \ + list_for_each_off(h, i, list_off_var_(i, member)) + +/** + * list_for_each_rev - iterate through a list backwards. + * @h: the list_head + * @i: the structure containing the list_node + * @member: the list_node member of the structure + * + * This is a convenient wrapper to iterate @i over the entire list. It's + * a for loop, so you can break and continue as normal. + * + * Example: + * list_for_each_rev(&parent->children, child, list) + * printf("Name: %s\n", child->name); + */ +#define list_for_each_rev(h, i, member) \ + for (i = container_of_var(list_debug(h)->n.prev, i, member); \ + &i->member != &(h)->n; \ + i = container_of_var(i->member.prev, i, member)) + +/** + * list_for_each_safe - iterate through a list, maybe during deletion + * @h: the list_head + * @i: the structure containing the list_node + * @nxt: the structure containing the list_node + * @member: the list_node member of the structure + * + * This is a convenient wrapper to iterate @i over the entire list. It's + * a for loop, so you can break and continue as normal. The extra variable + * @nxt is used to hold the next element, so you can delete @i from the list. + * + * Example: + * struct child *next; + * list_for_each_safe(&parent->children, child, next, list) { + * list_del(&child->list); + * parent->num_children--; + * } + */ +#define list_for_each_safe(h, i, nxt, member) \ + list_for_each_safe_off(h, i, nxt, list_off_var_(i, member)) + +/** + * list_next - get the next entry in a list + * @h: the list_head + * @i: a pointer to an entry in the list. + * @member: the list_node member of the structure + * + * If @i was the last entry in the list, returns NULL. + * + * Example: + * struct child *second; + * second = list_next(&parent->children, first, list); + * if (!second) + * printf("No second child!\n"); + */ +#define list_next(h, i, member) \ + ((list_typeof(i))list_entry_or_null(list_debug(h), \ + (i)->member.next, \ + list_off_var_((i), member))) + +/** + * list_prev - get the previous entry in a list + * @h: the list_head + * @i: a pointer to an entry in the list. + * @member: the list_node member of the structure + * + * If @i was the first entry in the list, returns NULL. + * + * Example: + * first = list_prev(&parent->children, second, list); + * if (!first) + * printf("Can't go back to first child?!\n"); + */ +#define list_prev(h, i, member) \ + ((list_typeof(i))list_entry_or_null(list_debug(h), \ + (i)->member.prev, \ + list_off_var_((i), member))) + +/** + * list_append_list - empty one list onto the end of another. + * @to: the list to append into + * @from: the list to empty. + * + * This takes the entire contents of @from and moves it to the end of + * @to. After this @from will be empty. + * + * Example: + * struct list_head adopter; + * + * list_append_list(&adopter, &parent->children); + * assert(list_empty(&parent->children)); + * parent->num_children = 0; + */ +static inline void list_append_list(struct list_head *to, + struct list_head *from) +{ + struct list_node *from_tail = list_debug(from)->n.prev; + struct list_node *to_tail = list_debug(to)->n.prev; + + /* Sew in head and entire list. */ + to->n.prev = from_tail; + from_tail->next = &to->n; + to_tail->next = &from->n; + from->n.prev = to_tail; + + /* Now remove head. */ + list_del(&from->n); + list_head_init(from); +} + +/** + * list_prepend_list - empty one list into the start of another. + * @to: the list to prepend into + * @from: the list to empty. + * + * This takes the entire contents of @from and moves it to the start + * of @to. After this @from will be empty. + * + * Example: + * list_prepend_list(&adopter, &parent->children); + * assert(list_empty(&parent->children)); + * parent->num_children = 0; + */ +static inline void list_prepend_list(struct list_head *to, + struct list_head *from) +{ + struct list_node *from_tail = list_debug(from)->n.prev; + struct list_node *to_head = list_debug(to)->n.next; + + /* Sew in head and entire list. */ + to->n.next = &from->n; + from->n.prev = &to->n; + to_head->prev = from_tail; + from_tail->next = to_head; + + /* Now remove head. */ + list_del(&from->n); + list_head_init(from); +} + +/** + * list_for_each_off - iterate through a list of memory regions. + * @h: the list_head + * @i: the pointer to a memory region wich contains list node data. + * @off: offset(relative to @i) at which list node data resides. + * + * This is a low-level wrapper to iterate @i over the entire list, used to + * implement all oher, more high-level, for-each constructs. It's a for loop, + * so you can break and continue as normal. + * + * WARNING! Being the low-level macro that it is, this wrapper doesn't know + * nor care about the type of @i. The only assumtion made is that @i points + * to a chunk of memory that at some @offset, relative to @i, contains a + * properly filled `struct node_list' which in turn contains pointers to + * memory chunks and it's turtles all the way down. Whith all that in mind + * remember that given the wrong pointer/offset couple this macro will + * happilly churn all you memory untill SEGFAULT stops it, in other words + * caveat emptor. + * + * It is worth mentioning that one of legitimate use-cases for that wrapper + * is operation on opaque types with known offset for `struct list_node' + * member(preferably 0), because it allows you not to disclose the type of + * @i. + * + * Example: + * list_for_each_off(&parent->children, child, + * offsetof(struct child, list)) + * printf("Name: %s\n", child->name); + */ +#define list_for_each_off(h, i, off) \ + for (i = list_node_to_off_(list_debug(h)->n.next, (off)); \ + list_node_from_off_((void *)i, (off)) != &(h)->n; \ + i = list_node_to_off_(list_node_from_off_((void *)i, (off))->next, \ + (off))) + +/** + * list_for_each_safe_off - iterate through a list of memory regions, maybe + * during deletion + * @h: the list_head + * @i: the pointer to a memory region wich contains list node data. + * @nxt: the structure containing the list_node + * @off: offset(relative to @i) at which list node data resides. + * + * For details see `list_for_each_off' and `list_for_each_safe' + * descriptions. + * + * Example: + * list_for_each_safe_off(&parent->children, child, + * next, offsetof(struct child, list)) + * printf("Name: %s\n", child->name); + */ +#define list_for_each_safe_off(h, i, nxt, off) \ + for (i = list_node_to_off_(list_debug(h)->n.next, (off)), \ + nxt = list_node_to_off_(list_node_from_off_(i, (off))->next, \ + (off)); \ + list_node_from_off_(i, (off)) != &(h)->n; \ + i = nxt, \ + nxt = list_node_to_off_(list_node_from_off_(i, (off))->next, \ + (off))) + + +/* Other -off variants. */ +#define list_entry_off(n, type, off) \ + ((type *)list_node_from_off_((n), (off))) + +#define list_head_off(h, type, off) \ + ((type *)list_head_off((h), (off))) + +#define list_tail_off(h, type, off) \ + ((type *)list_tail_((h), (off))) + +#define list_add_off(h, n, off) \ + list_add((h), list_node_from_off_((n), (off))) + +#define list_del_off(n, off) \ + list_del(list_node_from_off_((n), (off))) + +#define list_del_from_off(h, n, off) \ + list_del_from(h, list_node_from_off_((n), (off))) + +/* Offset helper functions so we only single-evaluate. */ +static inline void *list_node_to_off_(struct list_node *node, size_t off) +{ + return (void *)((char *)node - off); +} +static inline struct list_node *list_node_from_off_(void *ptr, size_t off) +{ + return (struct list_node *)((char *)ptr + off); +} + +/* Get the offset of the member, but make sure it's a list_node. */ +#define list_off_(type, member) \ + (container_off(type, member) + \ + check_type(((type *)0)->member, struct list_node)) + +#define list_off_var_(var, member) \ + (container_off_var(var, member) + \ + check_type(var->member, struct list_node)) + +#if HAVE_TYPEOF +#define list_typeof(var) typeof(var) +#else +#define list_typeof(var) void * +#endif + +/* Returns member, or NULL if at end of list. */ +static inline void *list_entry_or_null(const struct list_head *h, + const struct list_node *n, + size_t off) +{ + if (n == &h->n) + return NULL; + return (char *)n - off; +} +#endif /* CCAN_LIST_H */ -- 1.8.1.2 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel