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| | /*
Copyright 2020 Google LLC
Use of this source code is governed by a BSD-style
license that can be found in the LICENSE file or at
https://developers.google.com/open-source/licenses/bsd
*/
#include "system.h"
#include "basics.h"
#include "blocksource.h"
#include "strbuf.h"
#include "reftable.h"
static void strbuf_return_block(void *b, struct reftable_block *dest)
{
memset(dest->data, 0xff, dest->len);
reftable_free(dest->data);
}
static void strbuf_close(void *b)
{
}
static int strbuf_read_block(void *v, struct reftable_block *dest, uint64_t off,
uint32_t size)
{
struct strbuf *b = (struct strbuf *)v;
assert(off + size <= b->len);
dest->data = reftable_calloc(size);
memcpy(dest->data, b->buf + off, size);
dest->len = size;
return size;
}
static uint64_t strbuf_size(void *b)
{
return ((struct strbuf *)b)->len;
}
struct reftable_block_source_vtable strbuf_vtable = {
.size = &strbuf_size,
.read_block = &strbuf_read_block,
.return_block = &strbuf_return_block,
.close = &strbuf_close,
};
void block_source_from_strbuf(struct reftable_block_source *bs,
struct strbuf *buf)
{
assert(bs->ops == NULL);
bs->ops = &strbuf_vtable;
bs->arg = buf;
}
static void malloc_return_block(void *b, struct reftable_block *dest)
{
memset(dest->data, 0xff, dest->len);
reftable_free(dest->data);
}
struct reftable_block_source_vtable malloc_vtable = {
.return_block = &malloc_return_block,
};
struct reftable_block_source malloc_block_source_instance = {
.ops = &malloc_vtable,
};
struct reftable_block_source malloc_block_source(void)
{
return malloc_block_source_instance;
}
struct file_block_source {
int fd;
uint64_t size;
};
static uint64_t file_size(void *b)
{
return ((struct file_block_source *)b)->size;
}
static void file_return_block(void *b, struct reftable_block *dest)
{
memset(dest->data, 0xff, dest->len);
reftable_free(dest->data);
}
static void file_close(void *b)
{
int fd = ((struct file_block_source *)b)->fd;
if (fd > 0) {
close(fd);
((struct file_block_source *)b)->fd = 0;
}
reftable_free(b);
}
static int file_read_block(void *v, struct reftable_block *dest, uint64_t off,
uint32_t size)
{
struct file_block_source *b = (struct file_block_source *)v;
assert(off + size <= b->size);
dest->data = reftable_malloc(size);
if (pread(b->fd, dest->data, size, off) != size)
return -1;
dest->len = size;
return size;
}
struct reftable_block_source_vtable file_vtable = {
.size = &file_size,
.read_block = &file_read_block,
.return_block = &file_return_block,
.close = &file_close,
};
int reftable_block_source_from_file(struct reftable_block_source *bs,
const char *name)
{
struct stat st = { 0 };
int err = 0;
int fd = open(name, O_RDONLY);
struct file_block_source *p = NULL;
if (fd < 0) {
if (errno == ENOENT) {
return REFTABLE_NOT_EXIST_ERROR;
}
return -1;
}
err = fstat(fd, &st);
if (err < 0)
return -1;
p = reftable_calloc(sizeof(struct file_block_source));
p->size = st.st_size;
p->fd = fd;
assert(bs->ops == NULL);
bs->ops = &file_vtable;
bs->arg = p;
return 0;
}
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