X-Git-Url: https://git.ozlabs.org/?p=ccan;a=blobdiff_plain;f=ccan%2Ftal%2Ftal.h;h=28be3f2034c133b276bc1a9e7f803df6fa033469;hp=1ed15c75f46fd664b6f57b10c65bcd8eb9790406;hb=680aa496521811e7c60afb940bcae5024f4c6adb;hpb=bb480e553f9d204b85a2e42de0be42c7b80eebda diff --git a/ccan/tal/tal.h b/ccan/tal/tal.h index 1ed15c75..28be3f20 100644 --- a/ccan/tal/tal.h +++ b/ccan/tal/tal.h @@ -31,7 +31,7 @@ typedef void tal_t; * int *p = tal(NULL, int); * *p = 1; */ -#define tal(ctx, type) \ +#define tal(ctx, type) \ ((type *)tal_alloc_((ctx), sizeof(type), false, TAL_LABEL(type, ""))) /** @@ -45,7 +45,7 @@ typedef void tal_t; * p = talz(NULL, int); * assert(*p == 0); */ -#define talz(ctx, type) \ +#define talz(ctx, type) \ ((type *)tal_alloc_((ctx), sizeof(type), true, TAL_LABEL(type, ""))) /** @@ -53,14 +53,15 @@ typedef void tal_t; * @p: NULL, or tal allocated object to free. * * This calls the destructors for p (if any), then does the same for all its - * children (recursively) before finally freeing the memory. + * children (recursively) before finally freeing the memory. It returns + * NULL, for convenience. * * Note: errno is preserved by this call. * * Example: - * tal_free(p); + * p = tal_free(p); */ -void tal_free(const tal_t *p); +void *tal_free(const tal_t *p); /** * tal_arr - allocate an array of objects. @@ -68,14 +69,17 @@ void tal_free(const tal_t *p); * @type: the type to allocate. * @count: the number to allocate. * + * Note that an object allocated with tal_arr() has a length property; + * see tal_count(). + * * Example: * p = tal_arr(NULL, int, 2); * p[0] = 0; * p[1] = 1; */ -#define tal_arr(ctx, type, count) \ - ((type *)tal_alloc_((ctx), tal_sizeof_(sizeof(type), (count)), false, \ - TAL_LABEL(type, "[]"))) +#define tal_arr(ctx, type, count) \ + ((type *)tal_alloc_arr_((ctx), sizeof(type), (count), false, \ + true, TAL_LABEL(type, "[]"))) /** * tal_arrz - allocate an array of zeroed objects. @@ -83,13 +87,16 @@ void tal_free(const tal_t *p); * @type: the type to allocate. * @count: the number to allocate. * + * Note that an object allocated with tal_arrz() has a length property; + * see tal_count(). + * * Example: * p = tal_arrz(NULL, int, 2); * assert(p[0] == 0 && p[1] == 0); */ #define tal_arrz(ctx, type, count) \ - ((type *)tal_alloc_((ctx), tal_sizeof_(sizeof(type), (count)), true, \ - TAL_LABEL(type, "[]"))) + ((type *)tal_alloc_arr_((ctx), sizeof(type), (count), true, \ + true, TAL_LABEL(type, "[]"))) /** * tal_resize - enlarge or reduce a tal_arr[z]. @@ -97,12 +104,13 @@ void tal_free(const tal_t *p); * @count: the number to allocate. * * This returns true on success (and may move *@p), or false on failure. + * If @p has a length property, it is updated on success. * * Example: * tal_resize(&p, 100); */ #define tal_resize(p, count) \ - tal_resize_((void **)(p), tal_sizeof_(sizeof**(p), (count))) + tal_resize_((void **)(p), sizeof**(p), (count)) /** * tal_steal - change the parent of a tal-allocated pointer. @@ -125,10 +133,92 @@ void tal_free(const tal_t *p); * tal_add_destructor - add a callback function when this context is destroyed. * @ptr: The tal allocated object. * @function: the function to call before it's freed. + * + * This is a more convenient form of tal_add_notifier(@ptr, + * TAL_NOTIFY_FREE, ...), in that the function prototype takes only @ptr. + * + * Note that this can only fail if your allocfn fails and your errorfn returns. */ #define tal_add_destructor(ptr, function) \ tal_add_destructor_((ptr), typesafe_cb(void, void *, (function), (ptr))) +/** + * tal_del_destructor - remove a destructor callback function. + * @ptr: The tal allocated object. + * @function: the function to call before it's freed. + * + * If @function has not been successfully added as a destructor, this returns + * false. + */ +#define tal_del_destructor(ptr, function) \ + tal_del_destructor_((ptr), typesafe_cb(void, void *, (function), (ptr))) + +enum tal_notify_type { + TAL_NOTIFY_FREE = 1, + TAL_NOTIFY_STEAL = 2, + TAL_NOTIFY_MOVE = 4, + TAL_NOTIFY_RESIZE = 8, + TAL_NOTIFY_RENAME = 16, + TAL_NOTIFY_ADD_CHILD = 32, + TAL_NOTIFY_DEL_CHILD = 64, + TAL_NOTIFY_ADD_NOTIFIER = 128, + TAL_NOTIFY_DEL_NOTIFIER = 256 +}; + +/** + * tal_add_notifier - add a callback function when this context changes. + * @ptr: The tal allocated object. + * @types: Bitwise OR of the types the callback is interested in. + * @callback: the function to call. + * + * Note that this can only fail if your allocfn fails and your errorfn + * returns. Also note that notifiers are not reliable in the case + * where an allocation fails, as they may be called before any + * allocation is actually done. + * + * TAL_NOTIFY_FREE is called when @ptr is freed, either directly or + * because an ancestor is freed: @info is the argument to tal_free(). + * It is exactly equivalent to a destructor, with more information. + * + * TAL_NOTIFY_STEAL is called when @ptr's parent changes: @info is the + * new parent. + * + * TAL_NOTIFY_MOVE is called when @ptr is realloced (via tal_resize) + * and moved. In this case, @ptr arg here is the new memory, and + * @info is the old pointer. + * + * TAL_NOTIFY_RESIZE is called when @ptr is realloced via tal_resize: + * @info is the new size, in bytes. If the pointer has moved, + * TAL_NOTIFY_MOVE callbacks are called first. + * + * TAL_NOTIFY_ADD_CHILD/TAL_NOTIFY_DEL_CHILD are called when @ptr is + * the context for a tal() allocating call, or a direct child is + * tal_free()d: @info is the child. Note that TAL_NOTIFY_DEL_CHILD is + * not called when this context is tal_free()d: TAL_NOTIFY_FREE is + * considered sufficient for that case. + * + * TAL_NOTIFY_ADD_NOTIFIER/TAL_NOTIFIER_DEL_NOTIFIER are called when a + * notifier is added or removed (not for this notifier): @info is the + * callback. This is also called for tal_add_destructor and + * tal_del_destructor. + */ +#define tal_add_notifier(ptr, types, callback) \ + tal_add_notifier_((ptr), (types), \ + typesafe_cb_postargs(void, tal_t *, (callback), \ + (ptr), \ + enum tal_notify_type, void *)) + +/** + * tal_del_notifier - remove a notifier callback function. + * @ptr: The tal allocated object. + * @callback: the function to call. + */ +#define tal_del_notifier(ptr, callback) \ + tal_del_notifier_((ptr), \ + typesafe_cb_postargs(void, void *, (callback), \ + (ptr), \ + enum tal_notify_type, void *)) + /** * tal_set_name - attach a name to a tal pointer. * @ptr: The tal allocated object. @@ -147,6 +237,15 @@ void tal_free(const tal_t *p); */ const char *tal_name(const tal_t *ptr); +/** + * tal_count - get the count of objects in a tal_arr. + * @ptr: The tal allocated object array. + * + * Returns 0 if @ptr has no length property, but we aware that that is + * also a valid size! + */ +size_t tal_count(const tal_t *ptr); + /** * tal_first - get the first tal object child. * @root: The tal allocated object to start with, or NULL. @@ -184,42 +283,8 @@ tal_t *tal_parent(const tal_t *ctx); */ #define tal_dup(ctx, type, p, n, extra) \ ((type *)tal_dup_((ctx), tal_typechk_(p, type *), \ - tal_sizeof_(sizeof(type), (n)), \ - tal_sizeof_(sizeof(type), (extra)), \ - TAL_LABEL(type, "[]"))) - -/** - * tal_strdup - duplicate a string - * @ctx: NULL, or tal allocated object to be parent. - * @p: the string to copy (can be take()). - */ -char *tal_strdup(const tal_t *ctx, const char *p); - -/** - * tal_strndup - duplicate a limited amount of a string. - * @ctx: NULL, or tal allocated object to be parent. - * @p: the string to copy (can be take()). - * @n: the maximum length to copy. - * - * Always gives a nul-terminated string, with strlen() <= @n. - */ -char *tal_strndup(const tal_t *ctx, const char *p, size_t n); - -/** - * tal_asprintf - allocate a formatted string - * @ctx: NULL, or tal allocated object to be parent. - * @fmt: the printf-style format (can be take()). - */ -char *tal_asprintf(const tal_t *ctx, const char *fmt, ...) PRINTF_FMT(2,3); - -/** - * tal_vasprintf - allocate a formatted string (va_list version) - * @ctx: NULL, or tal allocated object to be parent. - * @fmt: the printf-style format (can be take()). - * @va: the va_list containing the format args. - */ -char *tal_vasprintf(const tal_t *ctx, const char *fmt, va_list ap) - PRINTF_FMT(2,0); + sizeof(type), (n), (extra), \ + true, TAL_LABEL(type, "[]"))) /** @@ -240,6 +305,28 @@ void tal_set_backend(void *(*alloc_fn)(size_t size), void (*free_fn)(void *), void (*error_fn)(const char *msg)); +/** + * tal_expand - expand a tal array with contents. + * @a1p: a pointer to the tal array to expand. + * @a2: the second array (can be take()). + * @num2: the number of elements in the second array. + * + * Note that *@a1 and @a2 should be the same type. tal_count(@a1) will + * be increased by @num2. + * + * Example: + * int *arr1 = tal_arrz(NULL, int, 2); + * int arr2[2] = { 1, 3 }; + * + * tal_expand(&arr1, arr2, 2); + * assert(tal_count(arr1) == 4); + * assert(arr1[2] == 1); + * assert(arr1[3] == 3); + */ +#define tal_expand(a1p, a2, num2) \ + tal_expand_((void **)(a1p), (a2), sizeof**(a1p), \ + (num2) + 0*sizeof(*(a1p) == (a2))) + /** * tal_check - set the allocation or error functions to use @@ -284,21 +371,6 @@ void tal_dump(void); bool tal_set_name_(tal_t *ctx, const char *name, bool literal); -static inline size_t tal_sizeof_(size_t size, size_t count) -{ - /* Multiplication wrap */ - if (count && unlikely(size * count / size != count)) - return (size_t)-1024; - - size *= count; - - /* Make sure we don't wrap adding header. */ - if (size > (size_t)-1024) - return (size_t)-1024; - - return size; -} - #if HAVE_TYPEOF #define tal_typeof(ptr) (__typeof__(ptr)) #if HAVE_STATEMENT_EXPR @@ -314,14 +386,25 @@ static inline size_t tal_sizeof_(size_t size, size_t count) #endif void *tal_alloc_(const tal_t *ctx, size_t bytes, bool clear, const char *label); +void *tal_alloc_arr_(const tal_t *ctx, size_t bytes, size_t count, bool clear, + bool add_count, const char *label); -void *tal_dup_(const tal_t *ctx, const void *p, size_t n, size_t extra, +void *tal_dup_(const tal_t *ctx, const void *p, size_t size, + size_t n, size_t extra, bool add_count, const char *label); tal_t *tal_steal_(const tal_t *new_parent, const tal_t *t); -bool tal_resize_(tal_t **ctxp, size_t size); +bool tal_resize_(tal_t **ctxp, size_t size, size_t count); +bool tal_expand_(tal_t **ctxp, const void *src, size_t size, size_t count); -bool tal_add_destructor_(tal_t *ctx, void (*destroy)(void *me)); +bool tal_add_destructor_(const tal_t *ctx, void (*destroy)(void *me)); +bool tal_del_destructor_(const tal_t *ctx, void (*destroy)(void *me)); +bool tal_add_notifier_(const tal_t *ctx, enum tal_notify_type types, + void (*notify)(tal_t *ctx, enum tal_notify_type, + void *info)); +bool tal_del_notifier_(const tal_t *ctx, + void (*notify)(tal_t *ctx, enum tal_notify_type, + void *info)); #endif /* CCAN_TAL_H */