mirror of
git://jb55.com/damus
synced 2024-09-16 02:03:45 +00:00
6863e74c0f
update flatcc, including the patch that fixes japanese usenames Changelog-Fixed: Fix japanese profiles names not loading
2051 lines
64 KiB
C
2051 lines
64 KiB
C
/*
|
|
* Codegenerator for C, building FlatBuffers.
|
|
*
|
|
* There are several approaches, some light, some requiring a library,
|
|
* some with vectored I/O etc.
|
|
*
|
|
* Here we focus on a reasonable balance of light code and efficiency.
|
|
*
|
|
* Builder code is generated to a separate file that includes the
|
|
* generated read-only code.
|
|
*
|
|
* Mutable buffers are not supported in this version.
|
|
*
|
|
*/
|
|
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
|
|
#include "flatcc_builder.h"
|
|
#include "flatcc_emitter.h"
|
|
|
|
/*
|
|
* `check` is designed to handle incorrect use errors that can be
|
|
* ignored in production of a tested product.
|
|
*
|
|
* `check_error` fails if condition is false and is designed to return an
|
|
* error code in production.
|
|
*/
|
|
|
|
#if FLATCC_BUILDER_ASSERT_ON_ERROR
|
|
#define check(cond, reason) FLATCC_BUILDER_ASSERT(cond, reason)
|
|
#else
|
|
#define check(cond, reason) ((void)0)
|
|
#endif
|
|
|
|
#if FLATCC_BUILDER_SKIP_CHECKS
|
|
#define check_error(cond, err, reason) ((void)0)
|
|
#else
|
|
#define check_error(cond, err, reason) if (!(cond)) { check(cond, reason); return err; }
|
|
#endif
|
|
|
|
/* `strnlen` not widely supported. */
|
|
static inline size_t pstrnlen(const char *s, size_t max_len)
|
|
{
|
|
const char *end = memchr(s, 0, max_len);
|
|
return end ? (size_t)(end - s) : max_len;
|
|
}
|
|
#undef strnlen
|
|
#define strnlen pstrnlen
|
|
|
|
/* Padding can be up to 255 zeroes, and 1 zero string termination byte.
|
|
* When two paddings are combined at nested buffers, we need twice that.
|
|
* Visible to emitter so it can test for zero padding in iov. */
|
|
const uint8_t flatcc_builder_padding_base[512] = { 0 };
|
|
#define _pad flatcc_builder_padding_base
|
|
|
|
#define uoffset_t flatbuffers_uoffset_t
|
|
#define soffset_t flatbuffers_soffset_t
|
|
#define voffset_t flatbuffers_voffset_t
|
|
#define utype_t flatbuffers_utype_t
|
|
|
|
#define write_uoffset __flatbuffers_uoffset_write_to_pe
|
|
#define write_voffset __flatbuffers_voffset_write_to_pe
|
|
#define write_identifier __flatbuffers_uoffset_write_to_pe
|
|
#define write_utype __flatbuffers_utype_write_to_pe
|
|
|
|
#define field_size sizeof(uoffset_t)
|
|
#define max_offset_count FLATBUFFERS_COUNT_MAX(field_size)
|
|
#define union_size sizeof(flatcc_builder_union_ref_t)
|
|
#define max_union_count FLATBUFFERS_COUNT_MAX(union_size)
|
|
#define utype_size sizeof(utype_t)
|
|
#define max_utype_count FLATBUFFERS_COUNT_MAX(utype_size)
|
|
|
|
#define max_string_len FLATBUFFERS_COUNT_MAX(1)
|
|
#define identifier_size FLATBUFFERS_IDENTIFIER_SIZE
|
|
|
|
|
|
#define iovec_t flatcc_iovec_t
|
|
#define frame_size sizeof(__flatcc_builder_frame_t)
|
|
#define frame(x) (B->frame[0].x)
|
|
|
|
|
|
/* `align` must be a power of 2. */
|
|
static inline uoffset_t alignup_uoffset(uoffset_t x, size_t align)
|
|
{
|
|
return (x + (uoffset_t)align - 1u) & ~((uoffset_t)align - 1u);
|
|
}
|
|
|
|
static inline size_t alignup_size(size_t x, size_t align)
|
|
{
|
|
return (x + align - 1u) & ~(align - 1u);
|
|
}
|
|
|
|
|
|
typedef struct vtable_descriptor vtable_descriptor_t;
|
|
struct vtable_descriptor {
|
|
/* Where the vtable is emitted. */
|
|
flatcc_builder_ref_t vt_ref;
|
|
/* Which buffer it was emitted to. */
|
|
uoffset_t nest_id;
|
|
/* Where the vtable is cached. */
|
|
uoffset_t vb_start;
|
|
/* Hash table collision chain. */
|
|
uoffset_t next;
|
|
};
|
|
|
|
typedef struct flatcc_iov_state flatcc_iov_state_t;
|
|
struct flatcc_iov_state {
|
|
size_t len;
|
|
int count;
|
|
flatcc_iovec_t iov[FLATCC_IOV_COUNT_MAX];
|
|
};
|
|
|
|
#define iov_state_t flatcc_iov_state_t
|
|
|
|
/* This assumes `iov_state_t iov;` has been declared in scope */
|
|
#define push_iov_cond(base, size, cond) if ((size) > 0 && (cond)) { iov.len += size;\
|
|
iov.iov[iov.count].iov_base = (void *)(base); iov.iov[iov.count].iov_len = (size); ++iov.count; }
|
|
#define push_iov(base, size) push_iov_cond(base, size, 1)
|
|
#define init_iov() { iov.len = 0; iov.count = 0; }
|
|
|
|
|
|
int flatcc_builder_default_alloc(void *alloc_context, iovec_t *b, size_t request, int zero_fill, int hint)
|
|
{
|
|
void *p;
|
|
size_t n;
|
|
|
|
(void)alloc_context;
|
|
|
|
if (request == 0) {
|
|
if (b->iov_base) {
|
|
FLATCC_BUILDER_FREE(b->iov_base);
|
|
b->iov_base = 0;
|
|
b->iov_len = 0;
|
|
}
|
|
return 0;
|
|
}
|
|
switch (hint) {
|
|
case flatcc_builder_alloc_ds:
|
|
n = 256;
|
|
break;
|
|
case flatcc_builder_alloc_ht:
|
|
/* Should be exact size, or space size is just wasted. */
|
|
n = request;
|
|
break;
|
|
case flatcc_builder_alloc_fs:
|
|
n = sizeof(__flatcc_builder_frame_t) * 8;
|
|
break;
|
|
case flatcc_builder_alloc_us:
|
|
n = 64;
|
|
break;
|
|
default:
|
|
/*
|
|
* We have many small structures - vs stack for tables with few
|
|
* elements, and few offset fields in patch log. No need to
|
|
* overallocate in case of busy small messages.
|
|
*/
|
|
n = 32;
|
|
break;
|
|
}
|
|
while (n < request) {
|
|
n *= 2;
|
|
}
|
|
if (request <= b->iov_len && b->iov_len / 2 >= n) {
|
|
/* Add hysteresis to shrink. */
|
|
return 0;
|
|
}
|
|
if (!(p = FLATCC_BUILDER_REALLOC(b->iov_base, n))) {
|
|
return -1;
|
|
}
|
|
/* Realloc might also shrink. */
|
|
if (zero_fill && b->iov_len < n) {
|
|
memset((uint8_t *)p + b->iov_len, 0, n - b->iov_len);
|
|
}
|
|
b->iov_base = p;
|
|
b->iov_len = n;
|
|
return 0;
|
|
}
|
|
|
|
#define T_ptr(base, pos) ((void *)((size_t)(base) + (size_t)(pos)))
|
|
#define ds_ptr(pos) (T_ptr(B->buffers[flatcc_builder_alloc_ds].iov_base, (pos)))
|
|
#define vs_ptr(pos) (T_ptr(B->buffers[flatcc_builder_alloc_vs].iov_base, (pos)))
|
|
#define pl_ptr(pos) (T_ptr(B->buffers[flatcc_builder_alloc_pl].iov_base, (pos)))
|
|
#define us_ptr(pos) (T_ptr(B->buffers[flatcc_builder_alloc_us].iov_base, (pos)))
|
|
#define vd_ptr(pos) (T_ptr(B->buffers[flatcc_builder_alloc_vd].iov_base, (pos)))
|
|
#define vb_ptr(pos) (T_ptr(B->buffers[flatcc_builder_alloc_vb].iov_base, (pos)))
|
|
#define vs_offset(ptr) ((uoffset_t)((size_t)(ptr) - (size_t)B->buffers[flatcc_builder_alloc_vs].iov_base))
|
|
#define pl_offset(ptr) ((uoffset_t)((size_t)(ptr) - (size_t)B->buffers[flatcc_builder_alloc_pl].iov_base))
|
|
#define us_offset(ptr) ((uoffset_t)((size_t)(ptr) - (size_t)B->buffers[flatcc_builder_alloc_us].iov_base))
|
|
|
|
#define table_limit (FLATBUFFERS_VOFFSET_MAX - field_size + 1)
|
|
#define data_limit (FLATBUFFERS_UOFFSET_MAX - field_size + 1)
|
|
|
|
#define set_identifier(id) memcpy(&B->identifier, (id) ? (void *)(id) : (void *)_pad, identifier_size)
|
|
|
|
/* Must also return true when no buffer has been started. */
|
|
#define is_top_buffer(B) (B->nest_id == 0)
|
|
|
|
/*
|
|
* Tables use a stack represention better suited for quickly adding
|
|
* fields to tables, but it must occasionally be refreshed following
|
|
* reallocation or reentry from child frame.
|
|
*/
|
|
static inline void refresh_ds(flatcc_builder_t *B, uoffset_t type_limit)
|
|
{
|
|
iovec_t *buf = B->buffers + flatcc_builder_alloc_ds;
|
|
|
|
B->ds = ds_ptr(B->ds_first);
|
|
B->ds_limit = (uoffset_t)buf->iov_len - B->ds_first;
|
|
/*
|
|
* So we don't allocate outside tables representation size, nor our
|
|
* current buffer size.
|
|
*/
|
|
if (B->ds_limit > type_limit) {
|
|
B->ds_limit = type_limit;
|
|
}
|
|
/* So exit frame can refresh fast. */
|
|
frame(type_limit) = type_limit;
|
|
}
|
|
|
|
static int reserve_ds(flatcc_builder_t *B, size_t need, uoffset_t limit)
|
|
{
|
|
iovec_t *buf = B->buffers + flatcc_builder_alloc_ds;
|
|
|
|
if (B->alloc(B->alloc_context, buf, B->ds_first + need, 1, flatcc_builder_alloc_ds)) {
|
|
return -1;
|
|
}
|
|
refresh_ds(B, limit);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Make sure there is always an extra zero termination on stack
|
|
* even if it isn't emitted such that string updates may count
|
|
* on zero termination being present always.
|
|
*/
|
|
static inline void *push_ds(flatcc_builder_t *B, uoffset_t size)
|
|
{
|
|
size_t offset;
|
|
|
|
offset = B->ds_offset;
|
|
if ((B->ds_offset += size) >= B->ds_limit) {
|
|
if (reserve_ds(B, B->ds_offset + 1, data_limit)) {
|
|
return 0;
|
|
}
|
|
}
|
|
return B->ds + offset;
|
|
}
|
|
|
|
static inline void unpush_ds(flatcc_builder_t *B, uoffset_t size)
|
|
{
|
|
B->ds_offset -= size;
|
|
memset(B->ds + B->ds_offset, 0, size);
|
|
}
|
|
|
|
static inline void *push_ds_copy(flatcc_builder_t *B, const void *data, uoffset_t size)
|
|
{
|
|
void *p;
|
|
|
|
if (!(p = push_ds(B, size))) {
|
|
return 0;
|
|
}
|
|
memcpy(p, data, size);
|
|
return p;
|
|
}
|
|
|
|
static inline void *push_ds_field(flatcc_builder_t *B, uoffset_t size, uint16_t align, voffset_t id)
|
|
{
|
|
uoffset_t offset;
|
|
|
|
/*
|
|
* We calculate table field alignment relative to first entry, not
|
|
* header field with vtable offset.
|
|
*
|
|
* Note: >= comparison handles special case where B->ds is not
|
|
* allocated yet and size is 0 so the return value would be mistaken
|
|
* for an error.
|
|
*/
|
|
offset = alignup_uoffset(B->ds_offset, align);
|
|
if ((B->ds_offset = offset + size) >= B->ds_limit) {
|
|
if (reserve_ds(B, B->ds_offset + 1, table_limit)) {
|
|
return 0;
|
|
}
|
|
}
|
|
B->vs[id] = (voffset_t)(offset + field_size);
|
|
if (id >= B->id_end) {
|
|
B->id_end = id + 1u;
|
|
}
|
|
return B->ds + offset;
|
|
}
|
|
|
|
static inline void *push_ds_offset_field(flatcc_builder_t *B, voffset_t id)
|
|
{
|
|
uoffset_t offset;
|
|
|
|
offset = alignup_uoffset(B->ds_offset, field_size);
|
|
if ((B->ds_offset = offset + field_size) > B->ds_limit) {
|
|
if (reserve_ds(B, B->ds_offset, table_limit)) {
|
|
return 0;
|
|
}
|
|
}
|
|
B->vs[id] = (voffset_t)(offset + field_size);
|
|
if (id >= B->id_end) {
|
|
B->id_end = id + 1u;
|
|
}
|
|
*B->pl++ = (flatbuffers_voffset_t)offset;
|
|
return B->ds + offset;
|
|
}
|
|
|
|
static inline void *reserve_buffer(flatcc_builder_t *B, int alloc_type, size_t used, size_t need, int zero_init)
|
|
{
|
|
iovec_t *buf = B->buffers + alloc_type;
|
|
|
|
if (used + need > buf->iov_len) {
|
|
if (B->alloc(B->alloc_context, buf, used + need, zero_init, alloc_type)) {
|
|
check(0, "memory allocation failed");
|
|
return 0;
|
|
}
|
|
}
|
|
return (void *)((size_t)buf->iov_base + used);
|
|
}
|
|
|
|
static inline int reserve_fields(flatcc_builder_t *B, int count)
|
|
{
|
|
size_t used, need;
|
|
|
|
/* Provide faster stack operations for common table operations. */
|
|
used = frame(container.table.vs_end) + frame(container.table.id_end) * sizeof(voffset_t);
|
|
need = (size_t)(count + 2) * sizeof(voffset_t);
|
|
if (!(B->vs = reserve_buffer(B, flatcc_builder_alloc_vs, used, need, 1))) {
|
|
return -1;
|
|
}
|
|
/* Move past header for convenience. */
|
|
B->vs += 2;
|
|
used = frame(container.table.pl_end);
|
|
/* Add one to handle special case of first table being empty. */
|
|
need = (size_t)count * sizeof(*(B->pl)) + 1;
|
|
if (!(B->pl = reserve_buffer(B, flatcc_builder_alloc_pl, used, need, 0))) {
|
|
return -1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int alloc_ht(flatcc_builder_t *B)
|
|
{
|
|
iovec_t *buf = B->buffers + flatcc_builder_alloc_ht;
|
|
|
|
size_t size, k;
|
|
/* Allocate null entry so we can check for return errors. */
|
|
FLATCC_ASSERT(B->vd_end == 0);
|
|
if (!reserve_buffer(B, flatcc_builder_alloc_vd, B->vd_end, sizeof(vtable_descriptor_t), 0)) {
|
|
return -1;
|
|
}
|
|
B->vd_end = sizeof(vtable_descriptor_t);
|
|
size = field_size * FLATCC_BUILDER_MIN_HASH_COUNT;
|
|
if (B->alloc(B->alloc_context, buf, size, 1, flatcc_builder_alloc_ht)) {
|
|
return -1;
|
|
}
|
|
while (size * 2 <= buf->iov_len) {
|
|
size *= 2;
|
|
}
|
|
size /= field_size;
|
|
for (k = 0; (((size_t)1) << k) < size; ++k) {
|
|
}
|
|
B->ht_width = k;
|
|
return 0;
|
|
}
|
|
|
|
static inline uoffset_t *lookup_ht(flatcc_builder_t *B, uint32_t hash)
|
|
{
|
|
uoffset_t *T;
|
|
|
|
if (B->ht_width == 0) {
|
|
if (alloc_ht(B)) {
|
|
return 0;
|
|
}
|
|
}
|
|
T = B->buffers[flatcc_builder_alloc_ht].iov_base;
|
|
|
|
return &T[FLATCC_BUILDER_BUCKET_VT_HASH(hash, B->ht_width)];
|
|
}
|
|
|
|
void flatcc_builder_flush_vtable_cache(flatcc_builder_t *B)
|
|
{
|
|
iovec_t *buf = B->buffers + flatcc_builder_alloc_ht;
|
|
|
|
if (B->ht_width == 0) {
|
|
return;
|
|
}
|
|
memset(buf->iov_base, 0, buf->iov_len);
|
|
/* Reserve the null entry. */
|
|
B->vd_end = sizeof(vtable_descriptor_t);
|
|
B->vb_end = 0;
|
|
}
|
|
|
|
int flatcc_builder_custom_init(flatcc_builder_t *B,
|
|
flatcc_builder_emit_fun *emit, void *emit_context,
|
|
flatcc_builder_alloc_fun *alloc, void *alloc_context)
|
|
{
|
|
/*
|
|
* Do not allocate anything here. Only the required buffers will be
|
|
* allocated. For simple struct buffers, no allocation is required
|
|
* at all.
|
|
*/
|
|
memset(B, 0, sizeof(*B));
|
|
|
|
if (emit == 0) {
|
|
B->is_default_emitter = 1;
|
|
emit = flatcc_emitter;
|
|
emit_context = &B->default_emit_context;
|
|
}
|
|
if (alloc == 0) {
|
|
alloc = flatcc_builder_default_alloc;
|
|
}
|
|
B->alloc_context = alloc_context;
|
|
B->alloc = alloc;
|
|
B->emit_context = emit_context;
|
|
B->emit = emit;
|
|
return 0;
|
|
}
|
|
|
|
int flatcc_builder_init(flatcc_builder_t *B)
|
|
{
|
|
return flatcc_builder_custom_init(B, 0, 0, 0, 0);
|
|
}
|
|
|
|
int flatcc_builder_custom_reset(flatcc_builder_t *B, int set_defaults, int reduce_buffers)
|
|
{
|
|
iovec_t *buf;
|
|
int i;
|
|
|
|
for (i = 0; i < FLATCC_BUILDER_ALLOC_BUFFER_COUNT; ++i) {
|
|
buf = B->buffers + i;
|
|
if (buf->iov_base) {
|
|
/* Don't try to reduce the hash table. */
|
|
if (i != flatcc_builder_alloc_ht &&
|
|
reduce_buffers && B->alloc(B->alloc_context, buf, 1, 1, i)) {
|
|
return -1;
|
|
}
|
|
memset(buf->iov_base, 0, buf->iov_len);
|
|
} else {
|
|
FLATCC_ASSERT(buf->iov_len == 0);
|
|
}
|
|
}
|
|
B->vb_end = 0;
|
|
if (B->vd_end > 0) {
|
|
/* Reset past null entry. */
|
|
B->vd_end = sizeof(vtable_descriptor_t);
|
|
}
|
|
B->min_align = 0;
|
|
B->emit_start = 0;
|
|
B->emit_end = 0;
|
|
B->level = 0;
|
|
B->limit_level = 0;
|
|
B->ds_offset = 0;
|
|
B->ds_limit = 0;
|
|
B->nest_count = 0;
|
|
B->nest_id = 0;
|
|
/* Needed for correct offset calculation. */
|
|
B->ds = B->buffers[flatcc_builder_alloc_ds].iov_base;
|
|
B->pl = B->buffers[flatcc_builder_alloc_pl].iov_base;
|
|
B->vs = B->buffers[flatcc_builder_alloc_vs].iov_base;
|
|
B->frame = 0;
|
|
if (set_defaults) {
|
|
B->vb_flush_limit = 0;
|
|
B->max_level = 0;
|
|
B->disable_vt_clustering = 0;
|
|
}
|
|
if (B->is_default_emitter) {
|
|
flatcc_emitter_reset(&B->default_emit_context);
|
|
}
|
|
if (B->refmap) {
|
|
flatcc_refmap_reset(B->refmap);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
int flatcc_builder_reset(flatcc_builder_t *B)
|
|
{
|
|
return flatcc_builder_custom_reset(B, 0, 0);
|
|
}
|
|
|
|
void flatcc_builder_clear(flatcc_builder_t *B)
|
|
{
|
|
iovec_t *buf;
|
|
int i;
|
|
|
|
for (i = 0; i < FLATCC_BUILDER_ALLOC_BUFFER_COUNT; ++i) {
|
|
buf = B->buffers + i;
|
|
B->alloc(B->alloc_context, buf, 0, 0, i);
|
|
}
|
|
if (B->is_default_emitter) {
|
|
flatcc_emitter_clear(&B->default_emit_context);
|
|
}
|
|
if (B->refmap) {
|
|
flatcc_refmap_clear(B->refmap);
|
|
}
|
|
memset(B, 0, sizeof(*B));
|
|
}
|
|
|
|
static inline void set_min_align(flatcc_builder_t *B, uint16_t align)
|
|
{
|
|
if (B->min_align < align) {
|
|
B->min_align = align;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* It's a max, but the minimum viable alignment is the largest observed
|
|
* alignment requirement, but no larger.
|
|
*/
|
|
static inline void get_min_align(uint16_t *align, uint16_t b)
|
|
{
|
|
if (*align < b) {
|
|
*align = b;
|
|
}
|
|
}
|
|
|
|
void *flatcc_builder_enter_user_frame_ptr(flatcc_builder_t *B, size_t size)
|
|
{
|
|
size_t *frame;
|
|
|
|
size = alignup_size(size, sizeof(size_t)) + sizeof(size_t);
|
|
|
|
if (!(frame = reserve_buffer(B, flatcc_builder_alloc_us, B->user_frame_end, size, 0))) {
|
|
return 0;
|
|
}
|
|
memset(frame, 0, size);
|
|
*frame++ = B->user_frame_offset;
|
|
B->user_frame_offset = B->user_frame_end + sizeof(size_t);
|
|
B->user_frame_end += size;
|
|
return frame;
|
|
}
|
|
|
|
size_t flatcc_builder_enter_user_frame(flatcc_builder_t *B, size_t size)
|
|
{
|
|
size_t *frame;
|
|
|
|
size = alignup_size(size, sizeof(size_t)) + sizeof(size_t);
|
|
|
|
if (!(frame = reserve_buffer(B, flatcc_builder_alloc_us, B->user_frame_end, size, 0))) {
|
|
return 0;
|
|
}
|
|
memset(frame, 0, size);
|
|
*frame++ = B->user_frame_offset;
|
|
B->user_frame_offset = B->user_frame_end + sizeof(size_t);
|
|
B->user_frame_end += size;
|
|
return B->user_frame_offset;
|
|
}
|
|
|
|
|
|
size_t flatcc_builder_exit_user_frame(flatcc_builder_t *B)
|
|
{
|
|
size_t *hdr;
|
|
|
|
FLATCC_ASSERT(B->user_frame_offset > 0);
|
|
|
|
hdr = us_ptr(B->user_frame_offset);
|
|
B->user_frame_end = B->user_frame_offset - sizeof(size_t);
|
|
return B->user_frame_offset = hdr[-1];
|
|
}
|
|
|
|
size_t flatcc_builder_exit_user_frame_at(flatcc_builder_t *B, size_t handle)
|
|
{
|
|
FLATCC_ASSERT(B->user_frame_offset >= handle);
|
|
|
|
B->user_frame_offset = handle;
|
|
return flatcc_builder_exit_user_frame(B);
|
|
}
|
|
|
|
size_t flatcc_builder_get_current_user_frame(flatcc_builder_t *B)
|
|
{
|
|
return B->user_frame_offset;
|
|
}
|
|
|
|
void *flatcc_builder_get_user_frame_ptr(flatcc_builder_t *B, size_t handle)
|
|
{
|
|
return us_ptr(handle);
|
|
}
|
|
|
|
static int enter_frame(flatcc_builder_t *B, uint16_t align)
|
|
{
|
|
if (++B->level > B->limit_level) {
|
|
if (B->max_level > 0 && B->level > B->max_level) {
|
|
return -1;
|
|
}
|
|
if (!(B->frame = reserve_buffer(B, flatcc_builder_alloc_fs,
|
|
(size_t)(B->level - 1) * frame_size, frame_size, 0))) {
|
|
return -1;
|
|
}
|
|
B->limit_level = (int)(B->buffers[flatcc_builder_alloc_fs].iov_len / frame_size);
|
|
if (B->max_level > 0 && B->max_level < B->limit_level) {
|
|
B->limit_level = B->max_level;
|
|
}
|
|
} else {
|
|
++B->frame;
|
|
}
|
|
frame(ds_offset) = B->ds_offset;
|
|
frame(align) = B->align;
|
|
B->align = align;
|
|
/* Note: do not assume padding before first has been allocated! */
|
|
frame(ds_first) = B->ds_first;
|
|
frame(type_limit) = data_limit;
|
|
B->ds_first = alignup_uoffset(B->ds_first + B->ds_offset, 8);
|
|
B->ds_offset = 0;
|
|
return 0;
|
|
}
|
|
|
|
static inline void exit_frame(flatcc_builder_t *B)
|
|
{
|
|
memset(B->ds, 0, B->ds_offset);
|
|
B->ds_offset = frame(ds_offset);
|
|
B->ds_first = frame(ds_first);
|
|
refresh_ds(B, frame(type_limit));
|
|
|
|
/*
|
|
* Restore local alignment: e.g. a table should not change alignment
|
|
* because a child table was just created elsewhere in the buffer,
|
|
* but the overall alignment (min align), should be aware of it.
|
|
* Each buffer has its own min align that then migrates up without
|
|
* being affected by sibling or child buffers.
|
|
*/
|
|
set_min_align(B, B->align);
|
|
B->align = frame(align);
|
|
|
|
--B->frame;
|
|
--B->level;
|
|
}
|
|
|
|
static inline uoffset_t front_pad(flatcc_builder_t *B, uoffset_t size, uint16_t align)
|
|
{
|
|
return (uoffset_t)(B->emit_start - (flatcc_builder_ref_t)size) & (align - 1u);
|
|
}
|
|
|
|
static inline uoffset_t back_pad(flatcc_builder_t *B, uint16_t align)
|
|
{
|
|
return (uoffset_t)(B->emit_end) & (align - 1u);
|
|
}
|
|
|
|
static inline flatcc_builder_ref_t emit_front(flatcc_builder_t *B, iov_state_t *iov)
|
|
{
|
|
flatcc_builder_ref_t ref;
|
|
|
|
/*
|
|
* We might have overflow when including headers, but without
|
|
* headers we should have checks to prevent overflow in the
|
|
* uoffset_t range, hence we subtract 16 to be safe. With that
|
|
* guarantee we can also make a safe check on the soffset_t range.
|
|
*
|
|
* We only allow buffers half the theoritical size of
|
|
* FLATBUFFERS_UOFFSET_MAX so we can safely use signed references.
|
|
*
|
|
* NOTE: vtables vt_offset field is signed, and the check in create
|
|
* table only ensures the signed limit. The check would fail if the
|
|
* total buffer size could grow beyond UOFFSET_MAX, and we prevent
|
|
* that by limiting the lower end to SOFFSET_MIN, and the upper end
|
|
* at emit_back to SOFFSET_MAX.
|
|
*/
|
|
ref = B->emit_start - (flatcc_builder_ref_t)iov->len;
|
|
if ((iov->len > 16 && iov->len - 16 > FLATBUFFERS_UOFFSET_MAX) || ref >= B->emit_start) {
|
|
check(0, "buffer too large to represent");
|
|
return 0;
|
|
}
|
|
if (B->emit(B->emit_context, iov->iov, iov->count, ref, iov->len)) {
|
|
check(0, "emitter rejected buffer content");
|
|
return 0;
|
|
}
|
|
return B->emit_start = ref;
|
|
}
|
|
|
|
static inline flatcc_builder_ref_t emit_back(flatcc_builder_t *B, iov_state_t *iov)
|
|
{
|
|
flatcc_builder_ref_t ref;
|
|
|
|
ref = B->emit_end;
|
|
B->emit_end = ref + (flatcc_builder_ref_t)iov->len;
|
|
/*
|
|
* Similar to emit_front check, but since we only emit vtables and
|
|
* padding at the back, we are not concerned with iov->len overflow,
|
|
* only total buffer overflow.
|
|
*
|
|
* With this check, vtable soffset references at table header can
|
|
* still overflow in extreme cases, so this must be checked
|
|
* separately.
|
|
*/
|
|
if (B->emit_end < ref) {
|
|
check(0, "buffer too large to represent");
|
|
return 0;
|
|
}
|
|
if (B->emit(B->emit_context, iov->iov, iov->count, ref, iov->len)) {
|
|
check(0, "emitter rejected buffer content");
|
|
return 0;
|
|
}
|
|
/*
|
|
* Back references always return ref + 1 because ref == 0 is valid and
|
|
* should not be mistaken for error. vtables understand this.
|
|
*/
|
|
return ref + 1;
|
|
}
|
|
|
|
/* If nested we cannot pad the end of the buffer without moving the entire buffer, so we don't. */
|
|
static int align_buffer_end(flatcc_builder_t *B, uint16_t *align, uint16_t block_align, int is_nested)
|
|
{
|
|
size_t end_pad;
|
|
iov_state_t iov;
|
|
|
|
block_align = block_align ? block_align : B->block_align ? B->block_align : 1;
|
|
get_min_align(align, field_size);
|
|
get_min_align(align, block_align);
|
|
/* Pad end of buffer to multiple. */
|
|
if (!is_nested) {
|
|
end_pad = back_pad(B, *align);
|
|
if (end_pad) {
|
|
init_iov();
|
|
push_iov(_pad, end_pad);
|
|
if (0 == emit_back(B, &iov)) {
|
|
check(0, "emitter rejected buffer content");
|
|
return -1;
|
|
}
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
flatcc_builder_ref_t flatcc_builder_embed_buffer(flatcc_builder_t *B,
|
|
uint16_t block_align,
|
|
const void *data, size_t size, uint16_t align, flatcc_builder_buffer_flags_t flags)
|
|
{
|
|
uoffset_t size_field, pad;
|
|
iov_state_t iov;
|
|
int with_size = (flags & flatcc_builder_with_size) != 0;
|
|
|
|
if (align_buffer_end(B, &align, block_align, !is_top_buffer(B))) {
|
|
return 0;
|
|
}
|
|
pad = front_pad(B, (uoffset_t)(size + (with_size ? field_size : 0)), align);
|
|
write_uoffset(&size_field, (uoffset_t)size + pad);
|
|
init_iov();
|
|
/* Add ubyte vector size header if nested buffer. */
|
|
push_iov_cond(&size_field, field_size, !is_top_buffer(B));
|
|
push_iov(data, size);
|
|
push_iov(_pad, pad);
|
|
return emit_front(B, &iov);
|
|
}
|
|
|
|
flatcc_builder_ref_t flatcc_builder_create_buffer(flatcc_builder_t *B,
|
|
const char identifier[identifier_size], uint16_t block_align,
|
|
flatcc_builder_ref_t object_ref, uint16_t align, flatcc_builder_buffer_flags_t flags)
|
|
{
|
|
flatcc_builder_ref_t buffer_ref;
|
|
uoffset_t header_pad, id_size = 0;
|
|
uoffset_t object_offset, buffer_size, buffer_base;
|
|
iov_state_t iov;
|
|
flatcc_builder_identifier_t id_out = 0;
|
|
int is_nested = (flags & flatcc_builder_is_nested) != 0;
|
|
int with_size = (flags & flatcc_builder_with_size) != 0;
|
|
|
|
if (align_buffer_end(B, &align, block_align, is_nested)) {
|
|
return 0;
|
|
}
|
|
set_min_align(B, align);
|
|
if (identifier) {
|
|
FLATCC_ASSERT(sizeof(flatcc_builder_identifier_t) == identifier_size);
|
|
FLATCC_ASSERT(sizeof(flatcc_builder_identifier_t) == field_size);
|
|
memcpy(&id_out, identifier, identifier_size);
|
|
id_out = __flatbuffers_thash_read_from_le(&id_out);
|
|
write_identifier(&id_out, id_out);
|
|
}
|
|
id_size = id_out ? identifier_size : 0;
|
|
header_pad = front_pad(B, field_size + id_size + (uoffset_t)(with_size ? field_size : 0), align);
|
|
init_iov();
|
|
/* ubyte vectors size field wrapping nested buffer. */
|
|
push_iov_cond(&buffer_size, field_size, is_nested || with_size);
|
|
push_iov(&object_offset, field_size);
|
|
/* Identifiers are not always present in buffer. */
|
|
push_iov(&id_out, id_size);
|
|
push_iov(_pad, header_pad);
|
|
buffer_base = (uoffset_t)B->emit_start - (uoffset_t)iov.len + (uoffset_t)((is_nested || with_size) ? field_size : 0);
|
|
if (is_nested) {
|
|
write_uoffset(&buffer_size, (uoffset_t)B->buffer_mark - buffer_base);
|
|
} else {
|
|
/* Also include clustered vtables. */
|
|
write_uoffset(&buffer_size, (uoffset_t)B->emit_end - buffer_base);
|
|
}
|
|
write_uoffset(&object_offset, (uoffset_t)object_ref - buffer_base);
|
|
if (0 == (buffer_ref = emit_front(B, &iov))) {
|
|
check(0, "emitter rejected buffer content");
|
|
return 0;
|
|
}
|
|
return buffer_ref;
|
|
}
|
|
|
|
flatcc_builder_ref_t flatcc_builder_create_struct(flatcc_builder_t *B, const void *data, size_t size, uint16_t align)
|
|
{
|
|
size_t pad;
|
|
iov_state_t iov;
|
|
|
|
check(align >= 1, "align cannot be 0");
|
|
set_min_align(B, align);
|
|
pad = front_pad(B, (uoffset_t)size, align);
|
|
init_iov();
|
|
push_iov(data, size);
|
|
/*
|
|
* Normally structs will already be a multiple of their alignment,
|
|
* so this padding will not likely be emitted.
|
|
*/
|
|
push_iov(_pad, pad);
|
|
return emit_front(B, &iov);
|
|
}
|
|
|
|
int flatcc_builder_start_buffer(flatcc_builder_t *B,
|
|
const char identifier[identifier_size], uint16_t block_align, flatcc_builder_buffer_flags_t flags)
|
|
{
|
|
/*
|
|
* This saves the parent `min_align` in the align field since we
|
|
* shouldn't use that for the current buffer. `exit_frame`
|
|
* automatically aggregates align up, so it is updated when the
|
|
* buffer frame exits.
|
|
*/
|
|
if (enter_frame(B, B->min_align)) {
|
|
return -1;
|
|
}
|
|
/* B->align now has parent min_align, and child frames will save it. */
|
|
/* Since we allow objects to be created before the buffer at top level,
|
|
we need to respect min_align in that case. */
|
|
if (!is_top_buffer(B) || B->min_align == 0) {
|
|
B->min_align = 1;
|
|
}
|
|
/* Save the parent block align, and set proper defaults for this buffer. */
|
|
frame(container.buffer.block_align) = B->block_align;
|
|
B->block_align = block_align;
|
|
frame(container.buffer.flags = B->buffer_flags);
|
|
B->buffer_flags = (uint16_t)flags;
|
|
frame(container.buffer.mark) = B->buffer_mark;
|
|
frame(container.buffer.nest_id) = B->nest_id;
|
|
/*
|
|
* End of buffer when nested. Not defined for top-level because we
|
|
* here (on only here) permit strings etc. to be created before buffer start and
|
|
* because top-level buffer vtables can be clustered.
|
|
*/
|
|
B->buffer_mark = B->emit_start;
|
|
/* Must be 0 before and after entering top-level buffer, and unique otherwise. */
|
|
B->nest_id = B->nest_count++;
|
|
frame(container.buffer.identifier) = B->identifier;
|
|
set_identifier(identifier);
|
|
frame(type) = flatcc_builder_buffer;
|
|
return 0;
|
|
}
|
|
|
|
flatcc_builder_ref_t flatcc_builder_end_buffer(flatcc_builder_t *B, flatcc_builder_ref_t root)
|
|
{
|
|
flatcc_builder_ref_t buffer_ref;
|
|
flatcc_builder_buffer_flags_t flags;
|
|
|
|
flags = (flatcc_builder_buffer_flags_t)B->buffer_flags & flatcc_builder_with_size;
|
|
flags |= is_top_buffer(B) ? 0 : flatcc_builder_is_nested;
|
|
check(frame(type) == flatcc_builder_buffer, "expected buffer frame");
|
|
set_min_align(B, B->block_align);
|
|
if (0 == (buffer_ref = flatcc_builder_create_buffer(B, (void *)&B->identifier,
|
|
B->block_align, root, B->min_align, flags))) {
|
|
return 0;
|
|
}
|
|
B->buffer_mark = frame(container.buffer.mark);
|
|
B->nest_id = frame(container.buffer.nest_id);
|
|
B->identifier = frame(container.buffer.identifier);
|
|
B->buffer_flags = frame(container.buffer.flags);
|
|
B->block_align = frame(container.buffer.block_align);
|
|
|
|
exit_frame(B);
|
|
return buffer_ref;
|
|
}
|
|
|
|
void *flatcc_builder_start_struct(flatcc_builder_t *B, size_t size, uint16_t align)
|
|
{
|
|
/* Allocate space for the struct on the ds stack. */
|
|
if (enter_frame(B, align)) {
|
|
return 0;
|
|
}
|
|
frame(type) = flatcc_builder_struct;
|
|
refresh_ds(B, data_limit);
|
|
return push_ds(B, (uoffset_t)size);
|
|
}
|
|
|
|
void *flatcc_builder_struct_edit(flatcc_builder_t *B)
|
|
{
|
|
return B->ds;
|
|
}
|
|
|
|
flatcc_builder_ref_t flatcc_builder_end_struct(flatcc_builder_t *B)
|
|
{
|
|
flatcc_builder_ref_t object_ref;
|
|
|
|
check(frame(type) == flatcc_builder_struct, "expected struct frame");
|
|
if (0 == (object_ref = flatcc_builder_create_struct(B, B->ds, B->ds_offset, B->align))) {
|
|
return 0;
|
|
}
|
|
exit_frame(B);
|
|
return object_ref;
|
|
}
|
|
|
|
static inline int vector_count_add(flatcc_builder_t *B, uoffset_t count, uoffset_t max_count)
|
|
{
|
|
uoffset_t n, n1;
|
|
n = frame(container.vector.count);
|
|
n1 = n + count;
|
|
/*
|
|
* This prevents elem_size * count from overflowing iff max_vector
|
|
* has been set sensible. Without this check we might allocate to
|
|
* little on the ds stack and return a buffer the user thinks is
|
|
* much larger which of course is bad even though the buffer eventually
|
|
* would fail anyway.
|
|
*/
|
|
check_error(n <= n1 && n1 <= max_count, -1, "vector too large to represent");
|
|
frame(container.vector.count) = n1;
|
|
return 0;
|
|
}
|
|
|
|
void *flatcc_builder_extend_vector(flatcc_builder_t *B, size_t count)
|
|
{
|
|
if (vector_count_add(B, (uoffset_t)count, frame(container.vector.max_count))) {
|
|
return 0;
|
|
}
|
|
return push_ds(B, frame(container.vector.elem_size) * (uoffset_t)count);
|
|
}
|
|
|
|
void *flatcc_builder_vector_push(flatcc_builder_t *B, const void *data)
|
|
{
|
|
check(frame(type) == flatcc_builder_vector, "expected vector frame");
|
|
check_error(frame(container.vector.count) <= frame(container.vector.max_count), 0, "vector max count exceeded");
|
|
frame(container.vector.count) += 1;
|
|
return push_ds_copy(B, data, frame(container.vector.elem_size));
|
|
}
|
|
|
|
void *flatcc_builder_append_vector(flatcc_builder_t *B, const void *data, size_t count)
|
|
{
|
|
check(frame(type) == flatcc_builder_vector, "expected vector frame");
|
|
if (vector_count_add(B, (uoffset_t)count, frame(container.vector.max_count))) {
|
|
return 0;
|
|
}
|
|
return push_ds_copy(B, data, frame(container.vector.elem_size) * (uoffset_t)count);
|
|
}
|
|
|
|
flatcc_builder_ref_t *flatcc_builder_extend_offset_vector(flatcc_builder_t *B, size_t count)
|
|
{
|
|
if (vector_count_add(B, (uoffset_t)count, max_offset_count)) {
|
|
return 0;
|
|
}
|
|
return push_ds(B, (uoffset_t)(field_size * count));
|
|
}
|
|
|
|
flatcc_builder_ref_t *flatcc_builder_offset_vector_push(flatcc_builder_t *B, flatcc_builder_ref_t ref)
|
|
{
|
|
flatcc_builder_ref_t *p;
|
|
|
|
check(frame(type) == flatcc_builder_offset_vector, "expected offset vector frame");
|
|
if (frame(container.vector.count) == max_offset_count) {
|
|
return 0;
|
|
}
|
|
frame(container.vector.count) += 1;
|
|
if (0 == (p = push_ds(B, field_size))) {
|
|
return 0;
|
|
}
|
|
*p = ref;
|
|
return p;
|
|
}
|
|
|
|
flatcc_builder_ref_t *flatcc_builder_append_offset_vector(flatcc_builder_t *B, const flatcc_builder_ref_t *refs, size_t count)
|
|
{
|
|
check(frame(type) == flatcc_builder_offset_vector, "expected offset vector frame");
|
|
if (vector_count_add(B, (uoffset_t)count, max_offset_count)) {
|
|
return 0;
|
|
}
|
|
return push_ds_copy(B, refs, (uoffset_t)(field_size * count));
|
|
}
|
|
|
|
char *flatcc_builder_extend_string(flatcc_builder_t *B, size_t len)
|
|
{
|
|
check(frame(type) == flatcc_builder_string, "expected string frame");
|
|
if (vector_count_add(B, (uoffset_t)len, max_string_len)) {
|
|
return 0;
|
|
}
|
|
return push_ds(B, (uoffset_t)len);
|
|
}
|
|
|
|
char *flatcc_builder_append_string(flatcc_builder_t *B, const char *s, size_t len)
|
|
{
|
|
check(frame(type) == flatcc_builder_string, "expected string frame");
|
|
if (vector_count_add(B, (uoffset_t)len, max_string_len)) {
|
|
return 0;
|
|
}
|
|
return push_ds_copy(B, s, (uoffset_t)len);
|
|
}
|
|
|
|
char *flatcc_builder_append_string_str(flatcc_builder_t *B, const char *s)
|
|
{
|
|
return flatcc_builder_append_string(B, s, strlen(s));
|
|
}
|
|
|
|
char *flatcc_builder_append_string_strn(flatcc_builder_t *B, const char *s, size_t max_len)
|
|
{
|
|
return flatcc_builder_append_string(B, s, strnlen(s, max_len));
|
|
}
|
|
|
|
int flatcc_builder_truncate_vector(flatcc_builder_t *B, size_t count)
|
|
{
|
|
check(frame(type) == flatcc_builder_vector, "expected vector frame");
|
|
check_error(frame(container.vector.count) >= count, -1, "cannot truncate vector past empty");
|
|
frame(container.vector.count) -= (uoffset_t)count;
|
|
unpush_ds(B, frame(container.vector.elem_size) * (uoffset_t)count);
|
|
return 0;
|
|
}
|
|
|
|
int flatcc_builder_truncate_offset_vector(flatcc_builder_t *B, size_t count)
|
|
{
|
|
check(frame(type) == flatcc_builder_offset_vector, "expected offset vector frame");
|
|
check_error(frame(container.vector.count) >= (uoffset_t)count, -1, "cannot truncate vector past empty");
|
|
frame(container.vector.count) -= (uoffset_t)count;
|
|
unpush_ds(B, frame(container.vector.elem_size) * (uoffset_t)count);
|
|
return 0;
|
|
}
|
|
|
|
int flatcc_builder_truncate_string(flatcc_builder_t *B, size_t len)
|
|
{
|
|
check(frame(type) == flatcc_builder_string, "expected string frame");
|
|
check_error(frame(container.vector.count) >= len, -1, "cannot truncate string past empty");
|
|
frame(container.vector.count) -= (uoffset_t)len;
|
|
unpush_ds(B, (uoffset_t)len);
|
|
return 0;
|
|
}
|
|
|
|
int flatcc_builder_start_vector(flatcc_builder_t *B, size_t elem_size, uint16_t align, size_t max_count)
|
|
{
|
|
get_min_align(&align, field_size);
|
|
if (enter_frame(B, align)) {
|
|
return -1;
|
|
}
|
|
frame(container.vector.elem_size) = (uoffset_t)elem_size;
|
|
frame(container.vector.count) = 0;
|
|
frame(container.vector.max_count) = (uoffset_t)max_count;
|
|
frame(type) = flatcc_builder_vector;
|
|
refresh_ds(B, data_limit);
|
|
return 0;
|
|
}
|
|
|
|
int flatcc_builder_start_offset_vector(flatcc_builder_t *B)
|
|
{
|
|
if (enter_frame(B, field_size)) {
|
|
return -1;
|
|
}
|
|
frame(container.vector.elem_size) = field_size;
|
|
frame(container.vector.count) = 0;
|
|
frame(type) = flatcc_builder_offset_vector;
|
|
refresh_ds(B, data_limit);
|
|
return 0;
|
|
}
|
|
|
|
flatcc_builder_ref_t flatcc_builder_create_offset_vector(flatcc_builder_t *B,
|
|
const flatcc_builder_ref_t *vec, size_t count)
|
|
{
|
|
flatcc_builder_ref_t *_vec;
|
|
|
|
if (flatcc_builder_start_offset_vector(B)) {
|
|
return 0;
|
|
}
|
|
if (!(_vec = flatcc_builder_extend_offset_vector(B, count))) {
|
|
return 0;
|
|
}
|
|
memcpy(_vec, vec, count * field_size);
|
|
return flatcc_builder_end_offset_vector(B);
|
|
}
|
|
|
|
int flatcc_builder_start_string(flatcc_builder_t *B)
|
|
{
|
|
if (enter_frame(B, 1)) {
|
|
return -1;
|
|
}
|
|
frame(container.vector.elem_size) = 1;
|
|
frame(container.vector.count) = 0;
|
|
frame(type) = flatcc_builder_string;
|
|
refresh_ds(B, data_limit);
|
|
return 0;
|
|
}
|
|
|
|
int flatcc_builder_reserve_table(flatcc_builder_t *B, int count)
|
|
{
|
|
check(count >= 0, "cannot reserve negative count");
|
|
return reserve_fields(B, count);
|
|
}
|
|
|
|
int flatcc_builder_start_table(flatcc_builder_t *B, int count)
|
|
{
|
|
if (enter_frame(B, field_size)) {
|
|
return -1;
|
|
}
|
|
frame(container.table.vs_end) = vs_offset(B->vs);
|
|
frame(container.table.pl_end) = pl_offset(B->pl);
|
|
frame(container.table.vt_hash) = B->vt_hash;
|
|
frame(container.table.id_end) = B->id_end;
|
|
B->vt_hash = 0;
|
|
FLATCC_BUILDER_INIT_VT_HASH(B->vt_hash);
|
|
B->id_end = 0;
|
|
frame(type) = flatcc_builder_table;
|
|
if (reserve_fields(B, count)) {
|
|
return -1;
|
|
}
|
|
refresh_ds(B, table_limit);
|
|
return 0;
|
|
}
|
|
|
|
flatcc_builder_vt_ref_t flatcc_builder_create_vtable(flatcc_builder_t *B,
|
|
const voffset_t *vt, voffset_t vt_size)
|
|
{
|
|
flatcc_builder_vt_ref_t vt_ref;
|
|
iov_state_t iov;
|
|
voffset_t *vt_;
|
|
size_t i;
|
|
|
|
/*
|
|
* Only top-level buffer can cluster vtables because only it can
|
|
* extend beyond the end.
|
|
*
|
|
* We write the vtable after the referencing table to maintain
|
|
* the construction invariant that any offset reference has
|
|
* valid emitted data at a higher address, and also that any
|
|
* issued negative emit address represents an offset reference
|
|
* to some flatbuffer object or vector (or possibly a root
|
|
* struct).
|
|
*
|
|
* The vt_ref is stored as the reference + 1 to avoid having 0 as a
|
|
* valid reference (which usally means error). It also idententifies
|
|
* vtable references as the only uneven references, and the only
|
|
* references that can be used multiple times in the same buffer.
|
|
*
|
|
* We do the vtable conversion here so cached vtables can be built
|
|
* hashed and compared more efficiently, and so end users with
|
|
* direct vtable construction don't have to worry about endianness.
|
|
* This also ensures the hash function works the same wrt.
|
|
* collision frequency.
|
|
*/
|
|
|
|
if (!flatbuffers_is_native_pe()) {
|
|
/* Make space in vtable cache for temporary endian conversion. */
|
|
if (!(vt_ = reserve_buffer(B, flatcc_builder_alloc_vb, B->vb_end, vt_size, 0))) {
|
|
return 0;
|
|
}
|
|
for (i = 0; i < vt_size / sizeof(voffset_t); ++i) {
|
|
write_voffset(&vt_[i], vt[i]);
|
|
}
|
|
vt = vt_;
|
|
/* We don't need to free the reservation since we don't advance any base pointer. */
|
|
}
|
|
|
|
init_iov();
|
|
push_iov(vt, vt_size);
|
|
if (is_top_buffer(B) && !B->disable_vt_clustering) {
|
|
/* Note that `emit_back` already returns ref + 1 as we require for vtables. */
|
|
if (0 == (vt_ref = emit_back(B, &iov))) {
|
|
return 0;
|
|
}
|
|
} else {
|
|
if (0 == (vt_ref = emit_front(B, &iov))) {
|
|
return 0;
|
|
}
|
|
/*
|
|
* We don't have a valid 0 ref here, but to be consistent with
|
|
* clustered vtables we offset by one. This cannot be zero
|
|
* either.
|
|
*/
|
|
vt_ref += 1;
|
|
}
|
|
return vt_ref;
|
|
}
|
|
|
|
flatcc_builder_vt_ref_t flatcc_builder_create_cached_vtable(flatcc_builder_t *B,
|
|
const voffset_t *vt, voffset_t vt_size, uint32_t vt_hash)
|
|
{
|
|
vtable_descriptor_t *vd, *vd2;
|
|
uoffset_t *pvd, *pvd_head;
|
|
uoffset_t next;
|
|
voffset_t *vt_;
|
|
|
|
/* This just gets the hash table slot, we still have to inspect it. */
|
|
if (!(pvd_head = lookup_ht(B, vt_hash))) {
|
|
return 0;
|
|
}
|
|
pvd = pvd_head;
|
|
next = *pvd;
|
|
/* Tracks if there already is a cached copy. */
|
|
vd2 = 0;
|
|
while (next) {
|
|
vd = vd_ptr(next);
|
|
vt_ = vb_ptr(vd->vb_start);
|
|
if (vt_[0] != vt_size || 0 != memcmp(vt, vt_, vt_size)) {
|
|
pvd = &vd->next;
|
|
next = vd->next;
|
|
continue;
|
|
}
|
|
/* Can't share emitted vtables between buffers, */
|
|
if (vd->nest_id != B->nest_id) {
|
|
/* but we don't have to resubmit to cache. */
|
|
vd2 = vd;
|
|
/* See if there is a better match. */
|
|
pvd = &vd->next;
|
|
next = vd->next;
|
|
continue;
|
|
}
|
|
/* Move to front hash strategy. */
|
|
if (pvd != pvd_head) {
|
|
*pvd = vd->next;
|
|
vd->next = *pvd_head;
|
|
*pvd_head = next;
|
|
}
|
|
/* vtable exists and has been emitted within current buffer. */
|
|
return vd->vt_ref;
|
|
}
|
|
/* Allocate new descriptor. */
|
|
if (!(vd = reserve_buffer(B, flatcc_builder_alloc_vd, B->vd_end, sizeof(vtable_descriptor_t), 0))) {
|
|
return 0;
|
|
}
|
|
next = B->vd_end;
|
|
B->vd_end += (uoffset_t)sizeof(vtable_descriptor_t);
|
|
|
|
/* Identify the buffer this vtable descriptor belongs to. */
|
|
vd->nest_id = B->nest_id;
|
|
|
|
/* Move to front hash strategy. */
|
|
vd->next = *pvd_head;
|
|
*pvd_head = next;
|
|
if (0 == (vd->vt_ref = flatcc_builder_create_vtable(B, vt, vt_size))) {
|
|
return 0;
|
|
}
|
|
if (vd2) {
|
|
/* Reuse cached copy. */
|
|
vd->vb_start = vd2->vb_start;
|
|
} else {
|
|
if (B->vb_flush_limit && B->vb_flush_limit < B->vb_end + vt_size) {
|
|
flatcc_builder_flush_vtable_cache(B);
|
|
} else {
|
|
/* Make space in vtable cache. */
|
|
if (!(vt_ = reserve_buffer(B, flatcc_builder_alloc_vb, B->vb_end, vt_size, 0))) {
|
|
return -1;
|
|
}
|
|
vd->vb_start = B->vb_end;
|
|
B->vb_end += vt_size;
|
|
memcpy(vt_, vt, vt_size);
|
|
}
|
|
}
|
|
return vd->vt_ref;
|
|
}
|
|
|
|
flatcc_builder_ref_t flatcc_builder_create_table(flatcc_builder_t *B, const void *data, size_t size, uint16_t align,
|
|
flatbuffers_voffset_t *offsets, int offset_count, flatcc_builder_vt_ref_t vt_ref)
|
|
{
|
|
int i;
|
|
uoffset_t pad, vt_offset, vt_offset_field, vt_base, base, offset, *offset_field;
|
|
iov_state_t iov;
|
|
|
|
check(offset_count >= 0, "expected non-negative offset_count");
|
|
/*
|
|
* vtable references are offset by 1 to avoid confusion with
|
|
* 0 as an error reference. It also uniquely identifies them
|
|
* as vtables being the only uneven reference type.
|
|
*/
|
|
check(vt_ref & 1, "invalid vtable referenc");
|
|
get_min_align(&align, field_size);
|
|
set_min_align(B, align);
|
|
/* Alignment is calculated for the first element, not the header. */
|
|
pad = front_pad(B, (uoffset_t)size, align);
|
|
base = (uoffset_t)B->emit_start - (uoffset_t)(pad + size + field_size);
|
|
/* Adjust by 1 to get unencoded vtable reference. */
|
|
vt_base = (uoffset_t)(vt_ref - 1);
|
|
vt_offset = base - vt_base;
|
|
/* Avoid overflow. */
|
|
if (base - vt_offset != vt_base) {
|
|
return -1;
|
|
}
|
|
/* Protocol endian encoding. */
|
|
write_uoffset(&vt_offset_field, vt_offset);
|
|
for (i = 0; i < offset_count; ++i) {
|
|
offset_field = (uoffset_t *)((size_t)data + offsets[i]);
|
|
offset = *offset_field - base - offsets[i] - (uoffset_t)field_size;
|
|
write_uoffset(offset_field, offset);
|
|
}
|
|
init_iov();
|
|
push_iov(&vt_offset_field, field_size);
|
|
push_iov(data, size);
|
|
push_iov(_pad, pad);
|
|
return emit_front(B, &iov);
|
|
}
|
|
|
|
int flatcc_builder_check_required_field(flatcc_builder_t *B, flatbuffers_voffset_t id)
|
|
{
|
|
check(frame(type) == flatcc_builder_table, "expected table frame");
|
|
|
|
return id < B->id_end && B->vs[id] != 0;
|
|
}
|
|
|
|
int flatcc_builder_check_union_field(flatcc_builder_t *B, flatbuffers_voffset_t id)
|
|
{
|
|
check(frame(type) == flatcc_builder_table, "expected table frame");
|
|
|
|
if (id == 0 || id >= B->id_end) {
|
|
return 0;
|
|
}
|
|
if (B->vs[id - 1] == 0) {
|
|
return B->vs[id] == 0;
|
|
}
|
|
if (*(uint8_t *)(B->ds + B->vs[id - 1])) {
|
|
return B->vs[id] != 0;
|
|
}
|
|
return B->vs[id] == 0;
|
|
}
|
|
|
|
int flatcc_builder_check_required(flatcc_builder_t *B, const flatbuffers_voffset_t *required, int count)
|
|
{
|
|
int i;
|
|
|
|
check(frame(type) == flatcc_builder_table, "expected table frame");
|
|
|
|
if (B->id_end < count) {
|
|
return 0;
|
|
}
|
|
for (i = 0; i < count; ++i) {
|
|
if (B->vs[required[i]] == 0) {
|
|
return 0;
|
|
}
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
flatcc_builder_ref_t flatcc_builder_end_table(flatcc_builder_t *B)
|
|
{
|
|
voffset_t *vt, vt_size;
|
|
flatcc_builder_ref_t table_ref, vt_ref;
|
|
int pl_count;
|
|
voffset_t *pl;
|
|
size_t tsize;
|
|
|
|
check(frame(type) == flatcc_builder_table, "expected table frame");
|
|
|
|
/* We have `ds_limit`, so we should not have to check for overflow here. */
|
|
|
|
vt = B->vs - 2;
|
|
vt_size = (voffset_t)(sizeof(voffset_t) * (B->id_end + 2u));
|
|
/* Update vtable header fields, first vtable size, then object table size. */
|
|
vt[0] = vt_size;
|
|
/*
|
|
* The `ds` buffer is always at least `field_size` aligned but excludes the
|
|
* initial vtable offset field. Therefore `field_size` is added here
|
|
* to the total table size in the vtable.
|
|
*/
|
|
tsize = (size_t)(B->ds_offset + field_size);
|
|
/*
|
|
* Tables are limited to 64K in standard FlatBuffers format due to the voffset
|
|
* 16 bit size, but we must also be able to store the table size, so the
|
|
* table payload has to be slightly less than that.
|
|
*/
|
|
check(tsize <= FLATBUFFERS_VOFFSET_MAX, "table too large");
|
|
vt[1] = (voffset_t)tsize;
|
|
FLATCC_BUILDER_UPDATE_VT_HASH(B->vt_hash, (uint32_t)vt[0], (uint32_t)vt[1]);
|
|
/* Find already emitted vtable, or emit a new one. */
|
|
if (!(vt_ref = flatcc_builder_create_cached_vtable(B, vt, vt_size, B->vt_hash))) {
|
|
return 0;
|
|
}
|
|
/* Clear vs stack so it is ready for the next vtable (ds stack is cleared by exit frame). */
|
|
memset(vt, 0, vt_size);
|
|
|
|
pl = pl_ptr(frame(container.table.pl_end));
|
|
pl_count = (int)(B->pl - pl);
|
|
if (0 == (table_ref = flatcc_builder_create_table(B, B->ds, B->ds_offset, B->align, pl, pl_count, vt_ref))) {
|
|
return 0;
|
|
}
|
|
B->vt_hash = frame(container.table.vt_hash);
|
|
B->id_end = frame(container.table.id_end);
|
|
B->vs = vs_ptr(frame(container.table.vs_end));
|
|
B->pl = pl_ptr(frame(container.table.pl_end));
|
|
exit_frame(B);
|
|
return table_ref;
|
|
}
|
|
|
|
flatcc_builder_ref_t flatcc_builder_create_vector(flatcc_builder_t *B,
|
|
const void *data, size_t count, size_t elem_size, uint16_t align, size_t max_count)
|
|
{
|
|
/*
|
|
* Note: it is important that vec_size is uoffset not size_t
|
|
* in case sizeof(uoffset_t) > sizeof(size_t) because max_count is
|
|
* defined in terms of uoffset_t representation size, and also
|
|
* because we risk accepting too large a vector even if max_count is
|
|
* not violated.
|
|
*/
|
|
uoffset_t vec_size, vec_pad, length_prefix;
|
|
iov_state_t iov;
|
|
|
|
check_error(count <= max_count, 0, "vector max_count violated");
|
|
get_min_align(&align, field_size);
|
|
set_min_align(B, align);
|
|
vec_size = (uoffset_t)count * (uoffset_t)elem_size;
|
|
/*
|
|
* That can happen on 32 bit systems when uoffset_t is defined as 64-bit.
|
|
* `emit_front/back` captures overflow, but not if our size type wraps first.
|
|
*/
|
|
#if FLATBUFFERS_UOFFSET_MAX > SIZE_MAX
|
|
check_error(vec_size < SIZE_MAX, 0, "vector larger than address space");
|
|
#endif
|
|
write_uoffset(&length_prefix, (uoffset_t)count);
|
|
/* Alignment is calculated for the first element, not the header. */
|
|
vec_pad = front_pad(B, vec_size, align);
|
|
init_iov();
|
|
push_iov(&length_prefix, field_size);
|
|
push_iov(data, vec_size);
|
|
push_iov(_pad, vec_pad);
|
|
return emit_front(B, &iov);
|
|
}
|
|
|
|
/*
|
|
* Note: FlatBuffers official documentation states that the size field of a
|
|
* vector is a 32-bit element count. It is not quite clear if the
|
|
* intention is to have the size field be of type uoffset_t since tables
|
|
* also have a uoffset_t sized header, or if the vector size should
|
|
* remain unchanged if uoffset is changed to 16- or 64-bits
|
|
* respectively. Since it makes most sense to have a vector compatible
|
|
* with the addressable space, we choose to use uoffset_t as size field,
|
|
* which remains compatible with the default 32-bit version of uoffset_t.
|
|
*/
|
|
flatcc_builder_ref_t flatcc_builder_end_vector(flatcc_builder_t *B)
|
|
{
|
|
flatcc_builder_ref_t vector_ref;
|
|
|
|
check(frame(type) == flatcc_builder_vector, "expected vector frame");
|
|
|
|
if (0 == (vector_ref = flatcc_builder_create_vector(B, B->ds,
|
|
frame(container.vector.count), frame(container.vector.elem_size),
|
|
B->align, frame(container.vector.max_count)))) {
|
|
return 0;
|
|
}
|
|
exit_frame(B);
|
|
return vector_ref;
|
|
}
|
|
|
|
size_t flatcc_builder_vector_count(flatcc_builder_t *B)
|
|
{
|
|
return frame(container.vector.count);
|
|
}
|
|
|
|
void *flatcc_builder_vector_edit(flatcc_builder_t *B)
|
|
{
|
|
return B->ds;
|
|
}
|
|
|
|
/* This function destroys the source content but avoids stack allocation. */
|
|
static flatcc_builder_ref_t _create_offset_vector_direct(flatcc_builder_t *B,
|
|
flatcc_builder_ref_t *vec, size_t count, const utype_t *types)
|
|
{
|
|
uoffset_t vec_size, vec_pad;
|
|
uoffset_t length_prefix, offset;
|
|
uoffset_t i;
|
|
soffset_t base;
|
|
iov_state_t iov;
|
|
|
|
if ((uoffset_t)count > max_offset_count) {
|
|
return 0;
|
|
}
|
|
set_min_align(B, field_size);
|
|
vec_size = (uoffset_t)(count * field_size);
|
|
write_uoffset(&length_prefix, (uoffset_t)count);
|
|
/* Alignment is calculated for the first element, not the header. */
|
|
vec_pad = front_pad(B, vec_size, field_size);
|
|
init_iov();
|
|
push_iov(&length_prefix, field_size);
|
|
push_iov(vec, vec_size);
|
|
push_iov(_pad, vec_pad);
|
|
base = B->emit_start - (soffset_t)iov.len;
|
|
for (i = 0; i < (uoffset_t)count; ++i) {
|
|
/*
|
|
* 0 is either end of buffer, start of vtables, or start of
|
|
* buffer depending on the direction in which the buffer is
|
|
* built. None of these can create a valid 0 reference but it
|
|
* is easy to create by mistake when manually building offset
|
|
* vectors.
|
|
*
|
|
* Unions do permit nulls, but only when the type is NONE.
|
|
*/
|
|
if (vec[i] != 0) {
|
|
offset = (uoffset_t)
|
|
(vec[i] - base - (soffset_t)(i * field_size) - (soffset_t)field_size);
|
|
write_uoffset(&vec[i], offset);
|
|
if (types) {
|
|
check(types[i] != 0, "union vector cannot have non-null element with type NONE");
|
|
}
|
|
} else {
|
|
if (types) {
|
|
check(types[i] == 0, "union vector cannot have null element without type NONE");
|
|
} else {
|
|
check(0, "offset vector cannot have null element");
|
|
}
|
|
}
|
|
}
|
|
return emit_front(B, &iov);
|
|
}
|
|
|
|
flatcc_builder_ref_t flatcc_builder_create_offset_vector_direct(flatcc_builder_t *B,
|
|
flatcc_builder_ref_t *vec, size_t count)
|
|
{
|
|
return _create_offset_vector_direct(B, vec, count, 0);
|
|
}
|
|
|
|
flatcc_builder_ref_t flatcc_builder_end_offset_vector(flatcc_builder_t *B)
|
|
{
|
|
flatcc_builder_ref_t vector_ref;
|
|
|
|
check(frame(type) == flatcc_builder_offset_vector, "expected offset vector frame");
|
|
if (0 == (vector_ref = flatcc_builder_create_offset_vector_direct(B,
|
|
(flatcc_builder_ref_t *)B->ds, frame(container.vector.count)))) {
|
|
return 0;
|
|
}
|
|
exit_frame(B);
|
|
return vector_ref;
|
|
}
|
|
|
|
flatcc_builder_ref_t flatcc_builder_end_offset_vector_for_unions(flatcc_builder_t *B, const utype_t *types)
|
|
{
|
|
flatcc_builder_ref_t vector_ref;
|
|
|
|
check(frame(type) == flatcc_builder_offset_vector, "expected offset vector frame");
|
|
if (0 == (vector_ref = _create_offset_vector_direct(B,
|
|
(flatcc_builder_ref_t *)B->ds, frame(container.vector.count), types))) {
|
|
return 0;
|
|
}
|
|
exit_frame(B);
|
|
return vector_ref;
|
|
}
|
|
|
|
void *flatcc_builder_offset_vector_edit(flatcc_builder_t *B)
|
|
{
|
|
return B->ds;
|
|
}
|
|
|
|
size_t flatcc_builder_offset_vector_count(flatcc_builder_t *B)
|
|
{
|
|
return frame(container.vector.count);
|
|
}
|
|
|
|
int flatcc_builder_table_add_union(flatcc_builder_t *B, int id,
|
|
flatcc_builder_union_ref_t uref)
|
|
{
|
|
flatcc_builder_ref_t *pref;
|
|
flatcc_builder_utype_t *putype;
|
|
|
|
check(frame(type) == flatcc_builder_table, "expected table frame");
|
|
check_error(uref.type != 0 || uref.value == 0, -1, "expected null value for type NONE");
|
|
if (uref.value != 0) {
|
|
pref = flatcc_builder_table_add_offset(B, id);
|
|
check_error(pref != 0, -1, "unable to add union value");
|
|
*pref = uref.value;
|
|
}
|
|
putype = flatcc_builder_table_add(B, id - 1, utype_size, utype_size);
|
|
check_error(putype != 0, -1, "unable to add union type");
|
|
write_utype(putype, uref.type);
|
|
return 0;
|
|
}
|
|
|
|
int flatcc_builder_table_add_union_vector(flatcc_builder_t *B, int id,
|
|
flatcc_builder_union_vec_ref_t uvref)
|
|
{
|
|
flatcc_builder_ref_t *pref;
|
|
|
|
check(frame(type) == flatcc_builder_table, "expected table frame");
|
|
check_error((uvref.type == 0) == (uvref.value == 0), -1, "expected both type and value vector, or neither");
|
|
if (uvref.type != 0) {
|
|
pref = flatcc_builder_table_add_offset(B, id - 1);
|
|
check_error(pref != 0, -1, "unable to add union member");
|
|
*pref = uvref.type;
|
|
|
|
pref = flatcc_builder_table_add_offset(B, id);
|
|
check_error(pref != 0, -1, "unable to add union member");
|
|
*pref = uvref.value;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
flatcc_builder_union_vec_ref_t flatcc_builder_create_union_vector(flatcc_builder_t *B,
|
|
const flatcc_builder_union_ref_t *urefs, size_t count)
|
|
{
|
|
flatcc_builder_union_vec_ref_t uvref = { 0, 0 };
|
|
flatcc_builder_utype_t *types;
|
|
flatcc_builder_ref_t *refs;
|
|
size_t i;
|
|
|
|
if (flatcc_builder_start_offset_vector(B)) {
|
|
return uvref;
|
|
}
|
|
if (0 == flatcc_builder_extend_offset_vector(B, count)) {
|
|
return uvref;
|
|
}
|
|
if (0 == (types = push_ds(B, (uoffset_t)(utype_size * count)))) {
|
|
return uvref;
|
|
}
|
|
|
|
/* Safe even if push_ds caused stack reallocation. */
|
|
refs = flatcc_builder_offset_vector_edit(B);
|
|
|
|
for (i = 0; i < count; ++i) {
|
|
types[i] = urefs[i].type;
|
|
refs[i] = urefs[i].value;
|
|
}
|
|
uvref = flatcc_builder_create_union_vector_direct(B,
|
|
types, refs, count);
|
|
/* No need to clean up after out temporary types vector. */
|
|
exit_frame(B);
|
|
return uvref;
|
|
}
|
|
|
|
flatcc_builder_union_vec_ref_t flatcc_builder_create_union_vector_direct(flatcc_builder_t *B,
|
|
const flatcc_builder_utype_t *types, flatcc_builder_ref_t *data, size_t count)
|
|
{
|
|
flatcc_builder_union_vec_ref_t uvref = { 0, 0 };
|
|
|
|
if (0 == (uvref.value = _create_offset_vector_direct(B, data, count, types))) {
|
|
return uvref;
|
|
}
|
|
if (0 == (uvref.type = flatcc_builder_create_type_vector(B, types, count))) {
|
|
return uvref;
|
|
}
|
|
return uvref;
|
|
}
|
|
|
|
flatcc_builder_ref_t flatcc_builder_create_type_vector(flatcc_builder_t *B,
|
|
const flatcc_builder_utype_t *types, size_t count)
|
|
{
|
|
return flatcc_builder_create_vector(B, types, count,
|
|
utype_size, utype_size, max_utype_count);
|
|
}
|
|
|
|
int flatcc_builder_start_union_vector(flatcc_builder_t *B)
|
|
{
|
|
if (enter_frame(B, field_size)) {
|
|
return -1;
|
|
}
|
|
frame(container.vector.elem_size) = union_size;
|
|
frame(container.vector.count) = 0;
|
|
frame(type) = flatcc_builder_union_vector;
|
|
refresh_ds(B, data_limit);
|
|
return 0;
|
|
}
|
|
|
|
flatcc_builder_union_vec_ref_t flatcc_builder_end_union_vector(flatcc_builder_t *B)
|
|
{
|
|
flatcc_builder_union_vec_ref_t uvref = { 0, 0 };
|
|
flatcc_builder_utype_t *types;
|
|
flatcc_builder_union_ref_t *urefs;
|
|
flatcc_builder_ref_t *refs;
|
|
size_t i, count;
|
|
|
|
check(frame(type) == flatcc_builder_union_vector, "expected union vector frame");
|
|
|
|
/*
|
|
* We could split the union vector in-place, but then we would have
|
|
* to deal with strict pointer aliasing rules which is not worthwhile
|
|
* so we create a new offset and type vector on the stack.
|
|
*
|
|
* We assume the stack is sufficiently aligned as is.
|
|
*/
|
|
count = flatcc_builder_union_vector_count(B);
|
|
if (0 == (refs = push_ds(B, (uoffset_t)(count * (utype_size + field_size))))) {
|
|
return uvref;
|
|
}
|
|
types = (flatcc_builder_utype_t *)(refs + count);
|
|
|
|
/* Safe even if push_ds caused stack reallocation. */
|
|
urefs = flatcc_builder_union_vector_edit(B);
|
|
|
|
for (i = 0; i < count; ++i) {
|
|
types[i] = urefs[i].type;
|
|
refs[i] = urefs[i].value;
|
|
}
|
|
uvref = flatcc_builder_create_union_vector_direct(B, types, refs, count);
|
|
/* No need to clean up after out temporary types vector. */
|
|
exit_frame(B);
|
|
return uvref;
|
|
}
|
|
|
|
void *flatcc_builder_union_vector_edit(flatcc_builder_t *B)
|
|
{
|
|
return B->ds;
|
|
}
|
|
|
|
size_t flatcc_builder_union_vector_count(flatcc_builder_t *B)
|
|
{
|
|
return frame(container.vector.count);
|
|
}
|
|
|
|
flatcc_builder_union_ref_t *flatcc_builder_extend_union_vector(flatcc_builder_t *B, size_t count)
|
|
{
|
|
if (vector_count_add(B, (uoffset_t)count, max_union_count)) {
|
|
return 0;
|
|
}
|
|
return push_ds(B, (uoffset_t)(union_size * count));
|
|
}
|
|
|
|
int flatcc_builder_truncate_union_vector(flatcc_builder_t *B, size_t count)
|
|
{
|
|
check(frame(type) == flatcc_builder_union_vector, "expected union vector frame");
|
|
check_error(frame(container.vector.count) >= (uoffset_t)count, -1, "cannot truncate vector past empty");
|
|
frame(container.vector.count) -= (uoffset_t)count;
|
|
unpush_ds(B, frame(container.vector.elem_size) * (uoffset_t)count);
|
|
return 0;
|
|
}
|
|
|
|
flatcc_builder_union_ref_t *flatcc_builder_union_vector_push(flatcc_builder_t *B,
|
|
flatcc_builder_union_ref_t uref)
|
|
{
|
|
flatcc_builder_union_ref_t *p;
|
|
|
|
check(frame(type) == flatcc_builder_union_vector, "expected union vector frame");
|
|
if (frame(container.vector.count) == max_union_count) {
|
|
return 0;
|
|
}
|
|
frame(container.vector.count) += 1;
|
|
if (0 == (p = push_ds(B, union_size))) {
|
|
return 0;
|
|
}
|
|
*p = uref;
|
|
return p;
|
|
}
|
|
|
|
flatcc_builder_union_ref_t *flatcc_builder_append_union_vector(flatcc_builder_t *B,
|
|
const flatcc_builder_union_ref_t *urefs, size_t count)
|
|
{
|
|
check(frame(type) == flatcc_builder_union_vector, "expected union vector frame");
|
|
if (vector_count_add(B, (uoffset_t)count, max_union_count)) {
|
|
return 0;
|
|
}
|
|
return push_ds_copy(B, urefs, (uoffset_t)(union_size * count));
|
|
}
|
|
|
|
flatcc_builder_ref_t flatcc_builder_create_string(flatcc_builder_t *B, const char *s, size_t len)
|
|
{
|
|
uoffset_t s_pad;
|
|
uoffset_t length_prefix;
|
|
iov_state_t iov;
|
|
|
|
if (len > max_string_len) {
|
|
return 0;
|
|
}
|
|
write_uoffset(&length_prefix, (uoffset_t)len);
|
|
/* Add 1 for zero termination. */
|
|
s_pad = front_pad(B, (uoffset_t)len + 1, field_size) + 1;
|
|
init_iov();
|
|
push_iov(&length_prefix, field_size);
|
|
push_iov(s, len);
|
|
push_iov(_pad, s_pad);
|
|
return emit_front(B, &iov);
|
|
}
|
|
|
|
flatcc_builder_ref_t flatcc_builder_create_string_str(flatcc_builder_t *B, const char *s)
|
|
{
|
|
return flatcc_builder_create_string(B, s, strlen(s));
|
|
}
|
|
|
|
flatcc_builder_ref_t flatcc_builder_create_string_strn(flatcc_builder_t *B, const char *s, size_t max_len)
|
|
{
|
|
return flatcc_builder_create_string(B, s, strnlen(s, max_len));
|
|
}
|
|
|
|
flatcc_builder_ref_t flatcc_builder_end_string(flatcc_builder_t *B)
|
|
{
|
|
flatcc_builder_ref_t string_ref;
|
|
|
|
check(frame(type) == flatcc_builder_string, "expected string frame");
|
|
FLATCC_ASSERT(frame(container.vector.count) == B->ds_offset);
|
|
if (0 == (string_ref = flatcc_builder_create_string(B,
|
|
(const char *)B->ds, B->ds_offset))) {
|
|
return 0;
|
|
}
|
|
exit_frame(B);
|
|
return string_ref;
|
|
}
|
|
|
|
char *flatcc_builder_string_edit(flatcc_builder_t *B)
|
|
{
|
|
return (char *)B->ds;
|
|
}
|
|
|
|
size_t flatcc_builder_string_len(flatcc_builder_t *B)
|
|
{
|
|
return frame(container.vector.count);
|
|
}
|
|
|
|
void *flatcc_builder_table_add(flatcc_builder_t *B, int id, size_t size, uint16_t align)
|
|
{
|
|
/*
|
|
* We align the offset relative to the first table field, excluding
|
|
* the header holding the vtable reference. On the stack, `ds_first`
|
|
* is aligned to 8 bytes thanks to the `enter_frame` logic, and this
|
|
* provides a safe way to update the fields on the stack, but here
|
|
* we are concerned with the target buffer alignment.
|
|
*
|
|
* We could also have aligned relative to the end of the table which
|
|
* would allow us to emit each field immediately, but it would be a
|
|
* confusing user experience wrt. field ordering, and it would add
|
|
* more variability to vtable layouts, thus reducing reuse, and
|
|
* frequent emissions to external emitter interface would be
|
|
* sub-optimal. Also, with that appoach, the vtable offsets would
|
|
* have to be adjusted at table end.
|
|
*
|
|
* As we have it, each emit occur at table end, vector end, string
|
|
* end, or buffer end, which might be helpful to various backend
|
|
* processors.
|
|
*/
|
|
check(frame(type) == flatcc_builder_table, "expected table frame");
|
|
check(id >= 0 && id <= (int)FLATBUFFERS_ID_MAX, "table id out of range");
|
|
if (align > B->align) {
|
|
B->align = align;
|
|
}
|
|
#if FLATCC_BUILDER_ALLOW_REPEAT_TABLE_ADD
|
|
if (B->vs[id] != 0) {
|
|
return B->ds + B->vs[id] - field_size;
|
|
}
|
|
#else
|
|
if (B->vs[id] != 0) {
|
|
check(0, "table field already set");
|
|
return 0;
|
|
}
|
|
#endif
|
|
FLATCC_BUILDER_UPDATE_VT_HASH(B->vt_hash, (uint32_t)id, (uint32_t)size);
|
|
return push_ds_field(B, (uoffset_t)size, align, (voffset_t)id);
|
|
}
|
|
|
|
void *flatcc_builder_table_edit(flatcc_builder_t *B, size_t size)
|
|
{
|
|
check(frame(type) == flatcc_builder_table, "expected table frame");
|
|
|
|
return B->ds + B->ds_offset - size;
|
|
}
|
|
|
|
void *flatcc_builder_table_add_copy(flatcc_builder_t *B, int id, const void *data, size_t size, uint16_t align)
|
|
{
|
|
void *p;
|
|
|
|
if ((p = flatcc_builder_table_add(B, id, size, align))) {
|
|
memcpy(p, data, size);
|
|
}
|
|
return p;
|
|
}
|
|
|
|
flatcc_builder_ref_t *flatcc_builder_table_add_offset(flatcc_builder_t *B, int id)
|
|
{
|
|
check(frame(type) == flatcc_builder_table, "expected table frame");
|
|
check(id >= 0 && id <= (int)FLATBUFFERS_ID_MAX, "table id out of range");
|
|
#if FLATCC_BUILDER_ALLOW_REPEAT_TABLE_ADD
|
|
if (B->vs[id] != 0) {
|
|
return B->ds + B->vs[id] - field_size;
|
|
}
|
|
#else
|
|
if (B->vs[id] != 0) {
|
|
check(0, "table field already set");
|
|
return 0;
|
|
}
|
|
#endif
|
|
FLATCC_BUILDER_UPDATE_VT_HASH(B->vt_hash, (uint32_t)id, (uint32_t)field_size);
|
|
return push_ds_offset_field(B, (voffset_t)id);
|
|
}
|
|
|
|
uint16_t flatcc_builder_push_buffer_alignment(flatcc_builder_t *B)
|
|
{
|
|
uint16_t old_min_align = B->min_align;
|
|
|
|
B->min_align = field_size;
|
|
return old_min_align;
|
|
}
|
|
|
|
void flatcc_builder_pop_buffer_alignment(flatcc_builder_t *B, uint16_t pushed_align)
|
|
{
|
|
set_min_align(B, pushed_align);
|
|
}
|
|
|
|
uint16_t flatcc_builder_get_buffer_alignment(flatcc_builder_t *B)
|
|
{
|
|
return B->min_align;
|
|
}
|
|
|
|
void flatcc_builder_set_vtable_clustering(flatcc_builder_t *B, int enable)
|
|
{
|
|
/* Inverted because we zero all memory in B on init. */
|
|
B->disable_vt_clustering = !enable;
|
|
}
|
|
|
|
void flatcc_builder_set_block_align(flatcc_builder_t *B, uint16_t align)
|
|
{
|
|
B->block_align = align;
|
|
}
|
|
|
|
int flatcc_builder_get_level(flatcc_builder_t *B)
|
|
{
|
|
return B->level;
|
|
}
|
|
|
|
void flatcc_builder_set_max_level(flatcc_builder_t *B, int max_level)
|
|
{
|
|
B->max_level = max_level;
|
|
if (B->limit_level < B->max_level) {
|
|
B->limit_level = B->max_level;
|
|
}
|
|
}
|
|
|
|
size_t flatcc_builder_get_buffer_size(flatcc_builder_t *B)
|
|
{
|
|
return (size_t)(B->emit_end - B->emit_start);
|
|
}
|
|
|
|
flatcc_builder_ref_t flatcc_builder_get_buffer_start(flatcc_builder_t *B)
|
|
{
|
|
return B->emit_start;
|
|
}
|
|
|
|
flatcc_builder_ref_t flatcc_builder_get_buffer_end(flatcc_builder_t *B)
|
|
{
|
|
return B->emit_end;
|
|
}
|
|
|
|
void flatcc_builder_set_vtable_cache_limit(flatcc_builder_t *B, size_t size)
|
|
{
|
|
B->vb_flush_limit = size;
|
|
}
|
|
|
|
void flatcc_builder_set_identifier(flatcc_builder_t *B, const char identifier[identifier_size])
|
|
{
|
|
set_identifier(identifier);
|
|
}
|
|
|
|
enum flatcc_builder_type flatcc_builder_get_type(flatcc_builder_t *B)
|
|
{
|
|
return B->frame ? frame(type) : flatcc_builder_empty;
|
|
}
|
|
|
|
enum flatcc_builder_type flatcc_builder_get_type_at(flatcc_builder_t *B, int level)
|
|
{
|
|
if (level < 1 || level > B->level) {
|
|
return flatcc_builder_empty;
|
|
}
|
|
return B->frame[level - B->level].type;
|
|
}
|
|
|
|
void *flatcc_builder_get_direct_buffer(flatcc_builder_t *B, size_t *size_out)
|
|
{
|
|
if (B->is_default_emitter) {
|
|
return flatcc_emitter_get_direct_buffer(&B->default_emit_context, size_out);
|
|
} else {
|
|
if (size_out) {
|
|
*size_out = 0;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
void *flatcc_builder_copy_buffer(flatcc_builder_t *B, void *buffer, size_t size)
|
|
{
|
|
/* User is allowed to call tentatively to see if there is support. */
|
|
if (!B->is_default_emitter) {
|
|
return 0;
|
|
}
|
|
buffer = flatcc_emitter_copy_buffer(&B->default_emit_context, buffer, size);
|
|
check(buffer, "default emitter declined to copy buffer");
|
|
return buffer;
|
|
}
|
|
|
|
void *flatcc_builder_finalize_buffer(flatcc_builder_t *B, size_t *size_out)
|
|
{
|
|
void * buffer;
|
|
size_t size;
|
|
|
|
size = flatcc_builder_get_buffer_size(B);
|
|
|
|
if (size_out) {
|
|
*size_out = size;
|
|
}
|
|
|
|
buffer = FLATCC_BUILDER_ALLOC(size);
|
|
|
|
if (!buffer) {
|
|
check(0, "failed to allocated memory for finalized buffer");
|
|
goto done;
|
|
}
|
|
if (!flatcc_builder_copy_buffer(B, buffer, size)) {
|
|
check(0, "default emitter declined to copy buffer");
|
|
FLATCC_BUILDER_FREE(buffer);
|
|
buffer = 0;
|
|
}
|
|
done:
|
|
if (!buffer && size_out) {
|
|
*size_out = 0;
|
|
}
|
|
return buffer;
|
|
}
|
|
|
|
void *flatcc_builder_finalize_aligned_buffer(flatcc_builder_t *B, size_t *size_out)
|
|
{
|
|
void * buffer;
|
|
size_t align;
|
|
size_t size;
|
|
|
|
size = flatcc_builder_get_buffer_size(B);
|
|
|
|
if (size_out) {
|
|
*size_out = size;
|
|
}
|
|
align = flatcc_builder_get_buffer_alignment(B);
|
|
|
|
size = (size + align - 1) & ~(align - 1);
|
|
buffer = FLATCC_BUILDER_ALIGNED_ALLOC(align, size);
|
|
|
|
if (!buffer) {
|
|
goto done;
|
|
}
|
|
if (!flatcc_builder_copy_buffer(B, buffer, size)) {
|
|
FLATCC_BUILDER_ALIGNED_FREE(buffer);
|
|
buffer = 0;
|
|
goto done;
|
|
}
|
|
done:
|
|
if (!buffer && size_out) {
|
|
*size_out = 0;
|
|
}
|
|
return buffer;
|
|
}
|
|
|
|
void *flatcc_builder_aligned_alloc(size_t alignment, size_t size)
|
|
{
|
|
return FLATCC_BUILDER_ALIGNED_ALLOC(alignment, size);
|
|
}
|
|
|
|
void flatcc_builder_aligned_free(void *p)
|
|
{
|
|
FLATCC_BUILDER_ALIGNED_FREE(p);
|
|
}
|
|
|
|
void *flatcc_builder_alloc(size_t size)
|
|
{
|
|
return FLATCC_BUILDER_ALLOC(size);
|
|
}
|
|
|
|
void flatcc_builder_free(void *p)
|
|
{
|
|
FLATCC_BUILDER_FREE(p);
|
|
}
|
|
|
|
void *flatcc_builder_get_emit_context(flatcc_builder_t *B)
|
|
{
|
|
return B->emit_context;
|
|
}
|