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author | Daniel Baumann <daniel@debian.org> | 2024-11-09 14:26:35 +0100 |
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committer | Daniel Baumann <daniel@debian.org> | 2024-11-09 14:26:35 +0100 |
commit | 47e4d7c791a050deb06e6c0fdfcac94a782a7cb9 (patch) | |
tree | 19edcac0f5dbda32bc329fa68773254fb2c488c3 /lib/darr.c | |
parent | Initial commit. (diff) | |
download | frr-47e4d7c791a050deb06e6c0fdfcac94a782a7cb9.tar.xz frr-47e4d7c791a050deb06e6c0fdfcac94a782a7cb9.zip |
Adding upstream version 10.1.1.upstream/10.1.1
Signed-off-by: Daniel Baumann <daniel@debian.org>
Diffstat (limited to 'lib/darr.c')
-rw-r--r-- | lib/darr.c | 159 |
1 files changed, 159 insertions, 0 deletions
diff --git a/lib/darr.c b/lib/darr.c new file mode 100644 index 00000000..7a012741 --- /dev/null +++ b/lib/darr.c @@ -0,0 +1,159 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * June 23 2023, Christian Hopps <chopps@labn.net> + * + * Copyright (c) 2023, LabN Consulting, L.L.C. + * + */ +#include <zebra.h> +#include "darr.h" +#include "memory.h" + +DEFINE_MTYPE(LIB, DARR, "Dynamic Array"); +DEFINE_MTYPE(LIB, DARR_STR, "Dynamic Array String"); + +static uint _msb(uint count) +{ + uint bit = 0; + int msb = 0; + + while (count) { + if (count & 1) + msb = bit; + count >>= 1; + bit += 1; + } + return msb; +} + +static uint darr_next_count(uint count, size_t esize) +{ + uint ncount; + + if (esize > sizeof(long long) && count == 1) + /* treat like a pointer */ + ncount = 1; + else { + uint msb = _msb(count); + + ncount = 1ull << msb; + /* if the users count wasn't a pow2 make it the next pow2. */ + if (ncount != count) { + assert(ncount < count); + ncount <<= 1; + if (esize < sizeof(long long) && ncount < 8) + ncount = 8; + } + } + return ncount; +} + +static size_t darr_size(uint count, size_t esize) +{ + return count * esize + sizeof(struct darr_metadata); +} + +char *__darr_in_vsprintf(char **sp, bool concat, const char *fmt, va_list ap) +{ + size_t inlen = concat ? darr_strlen(*sp) : 0; + size_t capcount = strlen(fmt) + MIN(inlen + 64, 128); + ssize_t len; + va_list ap_copy; + + darr_ensure_cap(*sp, capcount); + + if (!concat) + darr_reset(*sp); + + /* code below counts on having a NUL terminated string */ + if (darr_len(*sp) == 0) + *darr_append(*sp) = 0; +again: + va_copy(ap_copy, ap); + len = vsnprintf(darr_last(*sp), darr_avail(*sp) + 1, fmt, ap_copy); + va_end(ap_copy); + if (len < 0) + darr_in_strcat(*sp, fmt); + else if ((size_t)len <= darr_avail(*sp)) + _darr_len(*sp) += len; + else { + darr_ensure_cap(*sp, darr_len(*sp) + (size_t)len); + goto again; + } + return *sp; +} + +char *__darr_in_sprintf(char **sp, bool concat, const char *fmt, ...) +{ + va_list ap; + + va_start(ap, fmt); + (void)__darr_in_vsprintf(sp, concat, fmt, ap); + va_end(ap); + return *sp; +} + + +void *__darr_resize(void *a, uint count, size_t esize, struct memtype *mtype) +{ + uint ncount = darr_next_count(count, esize); + size_t osz = (a == NULL) ? 0 : darr_size(darr_cap(a), esize); + size_t sz = darr_size(ncount, esize); + struct darr_metadata *dm; + + if (a) { + dm = XREALLOC(_darr_meta(a)->mtype, _darr_meta(a), sz); + if (sz > osz) + memset((char *)dm + osz, 0, sz - osz); + } else { + dm = XCALLOC(mtype, sz); + dm->mtype = mtype; + } + dm->cap = ncount; + return (void *)(dm + 1); +} + + +void *__darr_insert_n(void *a, uint at, uint count, size_t esize, bool zero, + struct memtype *mtype) +{ + struct darr_metadata *dm; + uint olen, nlen; + + if (!a) + a = __darr_resize(NULL, at + count, esize, mtype); + dm = (struct darr_metadata *)a - 1; + olen = dm->len; + + // at == 1 + // count == 100 + // olen == 2 + + /* see if the user is expanding first using `at` */ + if (at >= olen) + nlen = at + count; + else + nlen = olen + count; + + if (nlen > dm->cap) { + a = __darr_resize(a, nlen, esize, mtype); + dm = (struct darr_metadata *)a - 1; + } + +#define _a_at(i) ((char *)a + ((i)*esize)) + if (at < olen) + memmove(_a_at(at + count), _a_at(at), esize * (olen - at)); + + dm->len = nlen; + + if (zero) { + if (at >= olen) { + at -= olen; + count += olen; + } + memset(_a_at(at), 0, esize * count); + } + + return a; +#undef _a_at +} |