diff options
| -rw-r--r-- | bftw.c | 2 | ||||
| -rw-r--r-- | dstring.c | 2 | ||||
| -rw-r--r-- | trie.c | 5 | ||||
| -rw-r--r-- | util.h | 23 |
4 files changed, 28 insertions, 4 deletions
@@ -300,7 +300,7 @@ static size_t bftw_child_nameoff(const struct bftw_file *parent) { /** Create a new bftw_file. */ static struct bftw_file *bftw_file_new(struct bftw_cache *cache, struct bftw_file *parent, const char *name) { size_t namelen = strlen(name); - size_t size = sizeof(struct bftw_file) + namelen + 1; + size_t size = BFS_FLEX_SIZEOF(struct bftw_file, name, namelen + 1); struct bftw_file *file = malloc(size); if (!file) { @@ -37,7 +37,7 @@ static struct dstring *dstrheader(const char *dstr) { /** Get the correct size for a dstring with the given capacity. */ static size_t dstrsize(size_t capacity) { - return sizeof(struct dstring) + capacity + 1; + return BFS_FLEX_SIZEOF(struct dstring, data, capacity + 1); } /** Allocate a dstring with the given contents. */ @@ -77,6 +77,7 @@ */ #include "trie.h" +#include "util.h" #include <assert.h> #include <limits.h> #include <stdbool.h> @@ -319,7 +320,7 @@ struct trie_leaf *trie_find_prefix(const struct trie *trie, const char *key) { /** Create a new leaf, holding a copy of the given key. */ static struct trie_leaf *new_trie_leaf(const void *key, size_t length) { - struct trie_leaf *leaf = malloc(sizeof(*leaf) + length); + struct trie_leaf *leaf = malloc(BFS_FLEX_SIZEOF(struct trie_leaf, key, length)); if (leaf) { leaf->value = NULL; leaf->length = length; @@ -335,7 +336,7 @@ static size_t trie_node_size(unsigned int size) { // Node size must be a power of two assert((size & (size - 1)) == 0); - return sizeof(struct trie_node) + size*sizeof(uintptr_t); + return BFS_FLEX_SIZEOF(struct trie_node, children, size); } /** Find the offset of the first nibble that differs between two keys. */ @@ -26,6 +26,7 @@ #include <fnmatch.h> #include <regex.h> #include <stdbool.h> +#include <stddef.h> #include <sys/types.h> // Some portability concerns @@ -91,6 +92,28 @@ # define BFS_FORMATTER(fmt, args) #endif +// Lower bound on BFS_FLEX_SIZEOF() +#define BFS_FLEX_LB(type, member, length) (offsetof(type, member) + sizeof(((type *)NULL)->member[0]) * (length)) + +// Maximum macro for BFS_FLEX_SIZE() +#define BFS_FLEX_MAX(a, b) ((a) > (b) ? (a) : (b)) + +/** + * Computes the size of a struct containing a flexible array member of the given + * length. + * + * @param type + * The type of the struct containing the flexible array. + * @param member + * The name of the flexible array member. + * @param length + * The length of the flexible array. + */ +#define BFS_FLEX_SIZEOF(type, member, length) \ + (sizeof(type) <= BFS_FLEX_LB(type, member, 0) \ + ? BFS_FLEX_LB(type, member, length) \ + : BFS_FLEX_MAX(sizeof(type), BFS_FLEX_LB(type, member, length))) + /** * readdir() wrapper that makes error handling cleaner. */ |