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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 07:24:22 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 07:24:22 +0000 |
commit | 45d6379135504814ab723b57f0eb8be23393a51d (patch) | |
tree | d4f2ec4acca824a8446387a758b0ce4238a4dffa /lib/isc/buffer.c | |
parent | Initial commit. (diff) | |
download | bind9-45d6379135504814ab723b57f0eb8be23393a51d.tar.xz bind9-45d6379135504814ab723b57f0eb8be23393a51d.zip |
Adding upstream version 1:9.16.44.upstream/1%9.16.44
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'lib/isc/buffer.c')
-rw-r--r-- | lib/isc/buffer.c | 542 |
1 files changed, 542 insertions, 0 deletions
diff --git a/lib/isc/buffer.c b/lib/isc/buffer.c new file mode 100644 index 0000000..b284840 --- /dev/null +++ b/lib/isc/buffer.c @@ -0,0 +1,542 @@ +/* + * Copyright (C) Internet Systems Consortium, Inc. ("ISC") + * + * SPDX-License-Identifier: MPL-2.0 + * + * This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, you can obtain one at https://mozilla.org/MPL/2.0/. + * + * See the COPYRIGHT file distributed with this work for additional + * information regarding copyright ownership. + */ + +/*! \file */ + +#include <inttypes.h> +#include <stdarg.h> +#include <stdbool.h> + +#include <isc/buffer.h> +#include <isc/mem.h> +#include <isc/print.h> +#include <isc/region.h> +#include <isc/string.h> +#include <isc/util.h> + +void +isc__buffer_init(isc_buffer_t *b, void *base, unsigned int length) { + /* + * Make 'b' refer to the 'length'-byte region starting at 'base'. + * XXXDCL see the comment in buffer.h about base being const. + */ + ISC__BUFFER_INIT(b, base, length); +} + +void +isc__buffer_initnull(isc_buffer_t *b) { + /* + * Initialize a new buffer which has no backing store. This can + * later be grown as needed and swapped in place. + */ + ISC__BUFFER_INIT(b, NULL, 0); +} + +void +isc_buffer_reinit(isc_buffer_t *b, void *base, unsigned int length) { + /* + * Re-initialize the buffer enough to reconfigure the base of the + * buffer. We will swap in the new buffer, after copying any + * data we contain into the new buffer and adjusting all of our + * internal pointers. + * + * The buffer must not be smaller than the length of the original + * buffer. + */ + REQUIRE(b->length <= length); + REQUIRE(base != NULL); + REQUIRE(!b->autore); + + if (b->length > 0U) { + (void)memmove(base, b->base, b->length); + } + + b->base = base; + b->length = length; +} + +void +isc__buffer_invalidate(isc_buffer_t *b) { + /* + * Make 'b' an invalid buffer. + */ + ISC__BUFFER_INVALIDATE(b); +} + +void +isc_buffer_setautorealloc(isc_buffer_t *b, bool enable) { + REQUIRE(ISC_BUFFER_VALID(b)); + REQUIRE(b->mctx != NULL); + b->autore = enable; +} + +void +isc__buffer_region(isc_buffer_t *b, isc_region_t *r) { + /* + * Make 'r' refer to the region of 'b'. + */ + ISC__BUFFER_REGION(b, r); +} + +void +isc__buffer_usedregion(const isc_buffer_t *b, isc_region_t *r) { + /* + * Make 'r' refer to the used region of 'b'. + */ + ISC__BUFFER_USEDREGION(b, r); +} + +void +isc__buffer_availableregion(isc_buffer_t *b, isc_region_t *r) { + /* + * Make 'r' refer to the available region of 'b'. + */ + ISC__BUFFER_AVAILABLEREGION(b, r); +} + +void +isc__buffer_add(isc_buffer_t *b, unsigned int n) { + /* + * Increase the 'used' region of 'b' by 'n' bytes. + */ + ISC__BUFFER_ADD(b, n); +} + +void +isc__buffer_subtract(isc_buffer_t *b, unsigned int n) { + /* + * Decrease the 'used' region of 'b' by 'n' bytes. + */ + ISC__BUFFER_SUBTRACT(b, n); +} + +void +isc__buffer_clear(isc_buffer_t *b) { + /* + * Make the used region empty. + */ + ISC__BUFFER_CLEAR(b); +} + +void +isc__buffer_consumedregion(isc_buffer_t *b, isc_region_t *r) { + /* + * Make 'r' refer to the consumed region of 'b'. + */ + ISC__BUFFER_CONSUMEDREGION(b, r); +} + +void +isc__buffer_remainingregion(isc_buffer_t *b, isc_region_t *r) { + /* + * Make 'r' refer to the remaining region of 'b'. + */ + ISC__BUFFER_REMAININGREGION(b, r); +} + +void +isc__buffer_activeregion(isc_buffer_t *b, isc_region_t *r) { + /* + * Make 'r' refer to the active region of 'b'. + */ + ISC__BUFFER_ACTIVEREGION(b, r); +} + +void +isc__buffer_setactive(isc_buffer_t *b, unsigned int n) { + /* + * Sets the end of the active region 'n' bytes after current. + */ + ISC__BUFFER_SETACTIVE(b, n); +} + +void +isc__buffer_first(isc_buffer_t *b) { + /* + * Make the consumed region empty. + */ + ISC__BUFFER_FIRST(b); +} + +void +isc__buffer_forward(isc_buffer_t *b, unsigned int n) { + /* + * Increase the 'consumed' region of 'b' by 'n' bytes. + */ + ISC__BUFFER_FORWARD(b, n); +} + +void +isc__buffer_back(isc_buffer_t *b, unsigned int n) { + /* + * Decrease the 'consumed' region of 'b' by 'n' bytes. + */ + ISC__BUFFER_BACK(b, n); +} + +void +isc_buffer_compact(isc_buffer_t *b) { + unsigned int length; + void *src; + + /* + * Compact the used region by moving the remaining region so it occurs + * at the start of the buffer. The used region is shrunk by the size + * of the consumed region, and the consumed region is then made empty. + */ + + REQUIRE(ISC_BUFFER_VALID(b)); + + src = isc_buffer_current(b); + length = isc_buffer_remaininglength(b); + if (length > 0U) { + (void)memmove(b->base, src, (size_t)length); + } + + if (b->active > b->current) { + b->active -= b->current; + } else { + b->active = 0; + } + b->current = 0; + b->used = length; +} + +uint8_t +isc_buffer_getuint8(isc_buffer_t *b) { + unsigned char *cp; + uint8_t result; + + /* + * Read an unsigned 8-bit integer from 'b' and return it. + */ + + REQUIRE(ISC_BUFFER_VALID(b)); + REQUIRE(b->used - b->current >= 1); + + cp = isc_buffer_current(b); + b->current += 1; + result = ((uint8_t)(cp[0])); + + return (result); +} + +void +isc__buffer_putuint8(isc_buffer_t *b, uint8_t val) { + ISC__BUFFER_PUTUINT8(b, val); +} + +uint16_t +isc_buffer_getuint16(isc_buffer_t *b) { + unsigned char *cp; + uint16_t result; + + /* + * Read an unsigned 16-bit integer in network byte order from 'b', + * convert it to host byte order, and return it. + */ + + REQUIRE(ISC_BUFFER_VALID(b)); + REQUIRE(b->used - b->current >= 2); + + cp = isc_buffer_current(b); + b->current += 2; + result = ((unsigned int)(cp[0])) << 8; + result |= ((unsigned int)(cp[1])); + + return (result); +} + +void +isc__buffer_putuint16(isc_buffer_t *b, uint16_t val) { + ISC__BUFFER_PUTUINT16(b, val); +} + +void +isc__buffer_putuint24(isc_buffer_t *b, uint32_t val) { + ISC__BUFFER_PUTUINT24(b, val); +} + +uint32_t +isc_buffer_getuint32(isc_buffer_t *b) { + unsigned char *cp; + uint32_t result; + + /* + * Read an unsigned 32-bit integer in network byte order from 'b', + * convert it to host byte order, and return it. + */ + + REQUIRE(ISC_BUFFER_VALID(b)); + REQUIRE(b->used - b->current >= 4); + + cp = isc_buffer_current(b); + b->current += 4; + result = ((unsigned int)(cp[0])) << 24; + result |= ((unsigned int)(cp[1])) << 16; + result |= ((unsigned int)(cp[2])) << 8; + result |= ((unsigned int)(cp[3])); + + return (result); +} + +void +isc__buffer_putuint32(isc_buffer_t *b, uint32_t val) { + ISC__BUFFER_PUTUINT32(b, val); +} + +uint64_t +isc_buffer_getuint48(isc_buffer_t *b) { + unsigned char *cp; + uint64_t result; + + /* + * Read an unsigned 48-bit integer in network byte order from 'b', + * convert it to host byte order, and return it. + */ + + REQUIRE(ISC_BUFFER_VALID(b)); + REQUIRE(b->used - b->current >= 6); + + cp = isc_buffer_current(b); + b->current += 6; + result = ((int64_t)(cp[0])) << 40; + result |= ((int64_t)(cp[1])) << 32; + result |= ((int64_t)(cp[2])) << 24; + result |= ((int64_t)(cp[3])) << 16; + result |= ((int64_t)(cp[4])) << 8; + result |= ((int64_t)(cp[5])); + + return (result); +} + +void +isc__buffer_putuint48(isc_buffer_t *b, uint64_t val) { + isc_result_t result; + uint16_t valhi; + uint32_t vallo; + + REQUIRE(ISC_BUFFER_VALID(b)); + if (ISC_UNLIKELY(b->autore)) { + result = isc_buffer_reserve(&b, 6); + REQUIRE(result == ISC_R_SUCCESS); + } + REQUIRE(isc_buffer_availablelength(b) >= 6); + + valhi = (uint16_t)(val >> 32); + vallo = (uint32_t)(val & 0xFFFFFFFF); + ISC__BUFFER_PUTUINT16(b, valhi); + ISC__BUFFER_PUTUINT32(b, vallo); +} + +void +isc__buffer_putmem(isc_buffer_t *b, const unsigned char *base, + unsigned int length) { + ISC__BUFFER_PUTMEM(b, base, length); +} + +void +isc__buffer_putstr(isc_buffer_t *b, const char *source) { + ISC__BUFFER_PUTSTR(b, source); +} + +void +isc_buffer_putdecint(isc_buffer_t *b, int64_t v) { + unsigned int l = 0; + unsigned char *cp; + char buf[21]; + isc_result_t result; + + REQUIRE(ISC_BUFFER_VALID(b)); + + /* xxxwpk do it more low-level way ? */ + l = snprintf(buf, 21, "%" PRId64, v); + RUNTIME_CHECK(l <= 21); + if (ISC_UNLIKELY(b->autore)) { + result = isc_buffer_reserve(&b, l); + REQUIRE(result == ISC_R_SUCCESS); + } + REQUIRE(isc_buffer_availablelength(b) >= l); + + cp = isc_buffer_used(b); + memmove(cp, buf, l); + b->used += l; +} + +isc_result_t +isc_buffer_dup(isc_mem_t *mctx, isc_buffer_t **dstp, const isc_buffer_t *src) { + isc_buffer_t *dst = NULL; + isc_region_t region; + isc_result_t result; + + REQUIRE(dstp != NULL && *dstp == NULL); + REQUIRE(ISC_BUFFER_VALID(src)); + + isc_buffer_usedregion(src, ®ion); + + isc_buffer_allocate(mctx, &dst, region.length); + + result = isc_buffer_copyregion(dst, ®ion); + RUNTIME_CHECK(result == ISC_R_SUCCESS); /* NOSPACE is impossible */ + *dstp = dst; + return (ISC_R_SUCCESS); +} + +isc_result_t +isc_buffer_copyregion(isc_buffer_t *b, const isc_region_t *r) { + isc_result_t result; + + REQUIRE(ISC_BUFFER_VALID(b)); + REQUIRE(r != NULL); + + if (ISC_UNLIKELY(b->autore)) { + result = isc_buffer_reserve(&b, r->length); + if (result != ISC_R_SUCCESS) { + return (result); + } + } + + if (r->length > isc_buffer_availablelength(b)) { + return (ISC_R_NOSPACE); + } + + if (r->length > 0U) { + memmove(isc_buffer_used(b), r->base, r->length); + b->used += r->length; + } + + return (ISC_R_SUCCESS); +} + +void +isc_buffer_allocate(isc_mem_t *mctx, isc_buffer_t **dynbuffer, + unsigned int length) { + REQUIRE(dynbuffer != NULL && *dynbuffer == NULL); + + isc_buffer_t *dbuf = isc_mem_get(mctx, sizeof(isc_buffer_t)); + unsigned char *bdata = isc_mem_get(mctx, length); + + isc_buffer_init(dbuf, bdata, length); + + ENSURE(ISC_BUFFER_VALID(dbuf)); + + dbuf->mctx = mctx; + + *dynbuffer = dbuf; +} + +isc_result_t +isc_buffer_reserve(isc_buffer_t **dynbuffer, unsigned int size) { + unsigned char *bdata; + uint64_t len; + + REQUIRE(dynbuffer != NULL); + REQUIRE(ISC_BUFFER_VALID(*dynbuffer)); + + len = (*dynbuffer)->length; + if ((len - (*dynbuffer)->used) >= size) { + return (ISC_R_SUCCESS); + } + + if ((*dynbuffer)->mctx == NULL) { + return (ISC_R_NOSPACE); + } + + /* Round to nearest buffer size increment */ + len = size + (*dynbuffer)->used; + len = (len + ISC_BUFFER_INCR - 1 - ((len - 1) % ISC_BUFFER_INCR)); + + /* Cap at UINT_MAX */ + if (len > UINT_MAX) { + len = UINT_MAX; + } + + if ((len - (*dynbuffer)->used) < size) { + return (ISC_R_NOMEMORY); + } + + /* + * XXXMUKS: This is far more expensive than plain realloc() as + * it doesn't remap pages, but does ordinary copy. So is + * isc_mem_reallocate(), which has additional issues. + */ + bdata = isc_mem_get((*dynbuffer)->mctx, (unsigned int)len); + + memmove(bdata, (*dynbuffer)->base, (*dynbuffer)->length); + isc_mem_put((*dynbuffer)->mctx, (*dynbuffer)->base, + (*dynbuffer)->length); + + (*dynbuffer)->base = bdata; + (*dynbuffer)->length = (unsigned int)len; + + return (ISC_R_SUCCESS); +} + +void +isc_buffer_free(isc_buffer_t **dynbuffer) { + isc_buffer_t *dbuf; + isc_mem_t *mctx; + + REQUIRE(dynbuffer != NULL); + REQUIRE(ISC_BUFFER_VALID(*dynbuffer)); + REQUIRE((*dynbuffer)->mctx != NULL); + + dbuf = *dynbuffer; + *dynbuffer = NULL; /* destroy external reference */ + mctx = dbuf->mctx; + dbuf->mctx = NULL; + + isc_mem_put(mctx, dbuf->base, dbuf->length); + isc_buffer_invalidate(dbuf); + isc_mem_put(mctx, dbuf, sizeof(isc_buffer_t)); +} + +isc_result_t +isc_buffer_printf(isc_buffer_t *b, const char *format, ...) { + va_list ap; + int n; + isc_result_t result; + + REQUIRE(ISC_BUFFER_VALID(b)); + + va_start(ap, format); + n = vsnprintf(NULL, 0, format, ap); + va_end(ap); + + if (n < 0) { + return (ISC_R_FAILURE); + } + + if (ISC_UNLIKELY(b->autore)) { + result = isc_buffer_reserve(&b, n + 1); + if (result != ISC_R_SUCCESS) { + return (result); + } + } + + if (isc_buffer_availablelength(b) < (unsigned int)n + 1) { + return (ISC_R_NOSPACE); + } + + va_start(ap, format); + n = vsnprintf(isc_buffer_used(b), n + 1, format, ap); + va_end(ap); + + if (n < 0) { + return (ISC_R_FAILURE); + } + + b->used += n; + + return (ISC_R_SUCCESS); +} |