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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-09 13:16:35 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-09 13:16:35 +0000
commite2bbf175a2184bd76f6c54ccf8456babeb1a46fc (patch)
treef0b76550d6e6f500ada964a3a4ee933a45e5a6f1 /lib/darr.h
parentInitial commit. (diff)
downloadfrr-e2bbf175a2184bd76f6c54ccf8456babeb1a46fc.tar.xz
frr-e2bbf175a2184bd76f6c54ccf8456babeb1a46fc.zip
Adding upstream version 9.1.upstream/9.1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'lib/darr.h')
-rw-r--r--lib/darr.h363
1 files changed, 363 insertions, 0 deletions
diff --git a/lib/darr.h b/lib/darr.h
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+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * June 23 2023, Christian Hopps <chopps@labn.net>
+ *
+ * Copyright (c) 2023, LabN Consulting, L.L.C.
+ *
+ * API functions:
+ * ==============
+ * - darr_append
+ * - darr_append_n
+ * - darr_append_nz
+ * - darr_cap
+ * - darr_ensure_cap
+ * - darr_ensure_i
+ * - darr_foreach_i
+ * - darr_foreach_p
+ * - darr_free
+ * - darr_insert
+ * - darr_insertz
+ * - darr_insert_n
+ * - darr_insert_nz
+ * - darr_len
+ * - darr_maxi
+ * - darr_pop
+ * - darr_push
+ * - darr_pushz
+ * - darr_remove
+ * - darr_remove_n
+ * - darr_reset
+ * - darr_setlen
+ */
+/*
+ * A few assured items
+ *
+ * - DAs will never have capacity 0 unless they are NULL pointers.
+ */
+#include <zebra.h>
+
+struct darr_metadata {
+ uint len;
+ uint cap;
+};
+void *__darr_insert_n(void *a, uint at, uint count, size_t esize, bool zero);
+void *__darr_resize(void *a, uint count, size_t esize);
+
+#define _darr_esize(A) sizeof((A)[0])
+#define darr_esize(A) sizeof((A)[0])
+#define _darr_len(A) _darr_meta(A)->len
+#define _darr_meta(A) (((struct darr_metadata *)(A)) - 1)
+#define _darr_resize(A, C) ({ (A) = __darr_resize((A), C, _darr_esize(A)); })
+
+/* Get the current capacity of the array */
+#define darr_cap(A) (((A) == NULL) ? 0 : _darr_meta(A)->cap)
+
+/* Get the largest possible index one can `darr_ensure_i` w/o resizing */
+#define darr_maxi(A) ((int)darr_cap(A) - 1)
+
+/**
+ * Get the current length of the array.
+ *
+ * As long as `A` is non-NULL, this macro may be used as an L-value to modify
+ * the length of the array.
+ *
+ * Args:
+ * A: The dynamic array, can be NULL.
+ *
+ * Return:
+ * The current length of the array.
+ */
+#define darr_len(A) (((A) == NULL) ? 0 : _darr_meta(A)->len)
+
+/**
+ * Set the current length of the array `A` to 0.
+ *
+ * Args:
+ * A: The dynamic array, can be NULL.
+ */
+#define darr_reset(A) \
+ do { \
+ if ((A)) \
+ _darr_len(A) = 0; \
+ } while (0)
+
+/**
+ * Set the current length of the array `A` to `L`.
+ *
+ * This function does *not* guarantee the memory is valid to L,
+ * use `darr_ensure` or `darr_ensure_cap` for that.
+ *
+ * Args:
+ * A: The dynamic array, can only be NULL if (L) == 0.
+ * L: The new length of the array.
+ */
+#define darr_setlen(A, L) \
+ do { \
+ assert((A) || !(L)); \
+ if ((A)) { \
+ /* have to cast to avoid compiler warning for "0" */ \
+ assert((long long)darr_cap(A) >= (L)); \
+ _darr_len(A) = (L); \
+ } \
+ } while (0)
+
+/**
+ * Free memory allocated for the dynamic array `A`
+ *
+ * Args:
+ * A: The dynamic array, can be NULL.
+ */
+
+#define darr_free(A) \
+ do { \
+ if ((A)) { \
+ free(_darr_meta(A)); \
+ (A) = NULL; \
+ } \
+ } while (0)
+
+/**
+ * Make sure that there is room in the dynamic array `A` for `C` elements.
+ *
+ * The value `A` may be changed as a result of this call in which case any
+ * pointers into the previous memory block are no longer valid. The `A` value
+ * is guaranteed not to change if there is sufficient capacity in the array.
+ *
+ * Args:
+ * A: (IN/OUT) the dynamic array, can be NULL.
+ * I: the index to guarantee memory exists for
+ *
+ * Return:
+ * A pointer to the (possibly moved) array.
+ */
+#define darr_ensure_cap(A, C) \
+ ({ \
+ if (darr_cap(A) < (C)) \
+ _darr_resize((A), (C)); \
+ (A); \
+ })
+
+/**
+ * Return a pointer to the (I)th element of array `A`, making sure there is
+ * room for the element.
+ *
+ * If the array length is less than `I + 1` then the length is set to `I + 1`.
+ *
+ * The value `A` may be changed as a result of this call in which case any
+ * pointers into the previous memory block are no longer valid. The `A` value
+ * is guaranteed not to change if there is sufficient capacity in the array.
+ *
+ * Args:
+ *
+ * A: (IN/OUT) the dynamic array, can be NULL.
+ * I: the index to guarantee memory exists for
+ *
+ * Return:
+ * A pointer to the (I)th element in `A`
+ */
+#define darr_ensure_i(A, I) \
+ ({ \
+ if ((int)(I) > darr_maxi(A)) \
+ _darr_resize((A), (I) + 1); \
+ if ((I) + 1 > _darr_len(A)) \
+ _darr_len(A) = (I) + 1; \
+ &(A)[I]; \
+ })
+
+#define _darr_insert_n(A, I, N, Z) \
+ ({ \
+ (A) = __darr_insert_n(A, I, N, _darr_esize(A), Z); \
+ &(A)[I]; \
+ })
+/**
+ * Insert N uninitialized elements in the array at index `I`.
+ *
+ * Previous elements from `I` are shifted right by `N`. Array length is
+ * increased by `N`.
+ *
+ * The value `A` may be changed as a result of this call in which case any
+ * pointers into the previous memory block are no longer valid. The `A` value
+ * is guaranteed not to change if there is sufficient capacity in the array.
+ *
+ * The `z` variant zeros new elements.
+ *
+ * Args:
+ * A: The dynamic array, can be NULL.
+ *
+ * Return:
+ * A pointer to the first inserted element in the array.
+ */
+#define darr_insert_n(A, I, N) _darr_insert_n(A, I, N, false)
+#define darr_insert_nz(A, I, N) _darr_insert_n(A, I, N, true)
+
+/**
+ * Insert an uninitialized element in the array at index `I`.
+ *
+ * Previous elements from `I` are shifted right by 1. Array length is
+ * increased by 1.
+ *
+ * The value `A` may be changed as a result of this call in which case any
+ * pointers into the previous memory block are no longer valid. The `A` value
+ * is guaranteed not to change if there is sufficient capacity in the array.
+ *
+ * The `z` variant zeros the new element.
+ *
+ * Args:
+ * A: The dynamic array, can be NULL.
+ *
+ * Return:
+ * A pointer to the element in the array.
+ */
+#define darr_insert(A, I) _darr_insert_n(A, I, 1, false)
+#define darr_insertz(A, I) _darr_insert_n(A, I, 1, true)
+
+/**
+ * Remove `N` elements from the array starting at index `I`.
+ *
+ * Elements from `I` + `N` are shifted left by `N`. Array length is reduced by
+ * `N`.
+ *
+ * Args:
+ * A: The dynamic array, can be NULL.
+ */
+#define darr_remove_n(A, I, N) \
+ do { \
+ uint __i = (I); \
+ uint __n = (N); \
+ uint __len = darr_len(A); \
+ if (!__len) \
+ break; \
+ else if (__i + __n < __len) { \
+ memmove(&(A)[__i], &(A)[__i + __n], \
+ _darr_esize(A) * (__len - (__i + __n))); \
+ _darr_len(A) = __len - __n; \
+ } else \
+ _darr_len(A) = __i; \
+ } while (0)
+
+/**
+ * Remove the `I`th element from the array.
+ *
+ * Previous elements from `I` + 1 are shifted left by 1, Array length is reduced
+ * by 1.
+ *
+ * Args:
+ * A: The dynamic array, can be NULL.
+ */
+#define darr_remove(A, I) darr_remove_n(A, I, 1)
+
+
+#define _darr_append_n(A, N, Z) \
+ ({ \
+ uint __len = darr_len(A); \
+ darr_ensure_cap(A, __len + (N)); \
+ _darr_len(A) = __len + (N); \
+ if (Z) \
+ memset(&(A)[__len], 0, (N)*_darr_esize(A)); \
+ &(A)[__len]; \
+ })
+/**
+ * Extending the array's length by N.
+ *
+ * Args:
+ * A: The dynamic array, can be NULL.
+ *
+ * The `z` variant zeros new elements.
+ *
+ * Return:
+ * A pointer to the first of the added elements at the end of the array.
+ */
+#define darr_append_n(A, N) _darr_append_n(A, N, false)
+#define darr_append_nz(A, N) _darr_append_n(A, N, true)
+
+/**
+ * Extending the array's length by 1.
+ *
+ * Args:
+ * A: The dynamic array, can be NULL.
+ *
+ * The `z` variant zeros the new element.
+ *
+ * Return:
+ * A pointer to the new element at the end of the array.
+ */
+#define darr_append(A) _darr_append_n(A, 1, false)
+#define darr_appendz(A) _darr_append_n(A, 1, true)
+
+/**
+ * Append an element `E` onto the array `A`, extending it's length by 1.
+ *
+ * The `z` variant zeros the new element.
+ *
+ * Args:
+ * A: The dynamic array, can be NULL.
+ *
+ * Return:
+ * A pointer to the element in the array.
+ */
+#define darr_push(A, E) (*darr_append(A) = (E))
+#define darr_pushz(A) (darr_appendz(A))
+
+
+/**
+ * Pop the last `N` elements from the array decrementing the length by `N`.
+ *
+ * Args:
+ * A: The dynamic array, can be NULL.
+ */
+#define darr_pop_n(A, N) \
+ do { \
+ if ((A) && (N) >= _darr_len(A)) \
+ darr_reset(A); \
+ else \
+ _darr_len(A) -= (N); \
+ } while (0)
+
+
+/**
+ * Pop the last element from the array decrementing the length by 1.
+ *
+ * Args:
+ * A: The dynamic array, can be NULL.
+ *
+ * Return:
+ * The element just popped.
+ */
+#define darr_pop(A) \
+ ({ \
+ uint __len = _darr_len(A); \
+ assert(__len); \
+ darr_remove(A, __len - 1); \
+ /* count on fact that we don't resize */ \
+ (A)[__len - 1]; \
+ })
+
+/**
+ * Return the address at the end of the array -- useful for iterating
+ *
+ * Args:
+ * A: The dynamic array, can be NULL.
+ *
+ * Return:
+ * The address of the end of the array (past the last elment) or NULL
+ * if `A` is NULL.
+ */
+#define darr_end(A) ((A) + darr_len(A))
+
+/**
+ * Iterate over array `A` using a pointer to each element in `P`.
+ *
+ * Args:
+ * A: The dynamic array, can be NULL.
+ * P: A variable with the same type as A used as the iterator.
+ */
+#define darr_foreach_p(A, P) for ((P) = (A); (P) < darr_end(A); (P)++)
+
+/**
+ * Iterate over array `A`s indices.
+ *
+ * Args:
+ * A: The dynamic array, can be NULL.
+ * I: A uint variable to store the current element index in.
+ */
+#define darr_foreach_i(A, I) for ((I) = 0; (I) < darr_len(A); (I)++)