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#ifndef DISFLUID_DISFLUID_CACHE_ENTRY_INCLUDED
# define DISFLUID_DISFLUID_CACHE_ENTRY_INCLUDED
# include <config.h>
# include "string-desc.h"
# include <stdbool.h>
MAYBE_UNUSED static int
db_mark_cache_entry (const char *db_root, const string_desc_t * id);
MAYBE_UNUSED static int
db_read_cache_entry (const char *db_root, const string_desc_t * id,
struct timespec *request_date,
struct timespec *response_date, bool *invalidated,
string_desc_t * key_id,
string_desc_t * response_header_id,
string_desc_t * response_body_id);
MAYBE_UNUSED static int
db_write_cache_entry (const char *db_root, string_desc_t * id,
const struct timespec *request_date,
const struct timespec *response_date, bool invalidated,
const string_desc_t * key_id,
const string_desc_t * response_header_id,
const string_desc_t * response_body_id);
# include "disfluid-db.h"
# include "safe-alloc.h"
MAYBE_UNUSED static int
db_mark_cache_entry (const char *db_root, const string_desc_t * id)
{
struct timespec request_date = { 0 }, response_date = { 0 };
bool invalidated = false;
string_desc_t key = { 0 }, header = { 0 }, body = { 0 };
int error = db_read_cache_entry (db_root, id, &request_date, &response_date,
&invalidated, &key, &header, &body);
if (error < 0)
{
goto cleanup;
}
int key_error = db_mark_leaf (db_root, &key);
int header_error = db_mark_leaf (db_root, &header);
int body_error = db_mark_leaf (db_root, &body);
if (key_error < 0 || header_error < 0 || body_error < 0)
{
error = -1;
}
cleanup:
FREE (key._data);
FREE (header._data);
FREE (body._data);
return error;
}
/* The cache entry file is organized as follows:
- on 16 bytes, "disfluid c.entry",
- on 8 bytes, the request date (timestamp in seconds),
- on 4 bytes, the request date (number of nanoseconds),
- on 8 bytes, the response date (timestamp in seconds),
- on 4 bytes, the response date (number of nanoseconds),
- on 32 bytes, the key digest,
- on 32 bytes, the header digest,
- on 32 bytes, the body digest,
- 80 if the entry has been artificially invalidated, 00 otherwise.
*/
static int
parse_timespec (const char *data, struct timespec *ts)
{
ts->tv_sec = 0;
ts->tv_nsec = 0;
for (size_t i = 0; i < 8; i++)
{
ts->tv_sec *= 256;
ts->tv_sec += (uint8_t) data[i];
}
for (size_t i = 0; i < 4; i++)
{
ts->tv_nsec *= 256;
ts->tv_nsec += (uint8_t) data[8 + i];
}
if (ts->tv_nsec < 1000000000)
{
return 0;
}
return -1;
}
static int
represent_timespec (char *data, const struct timespec *ts)
{
struct timespec cp = {.tv_sec = ts->tv_sec,.tv_nsec = ts->tv_nsec };
for (size_t i = 8; i-- > 0;)
{
data[i] = (char) (uint8_t) cp.tv_sec % 256;
cp.tv_sec /= 256;
}
for (size_t i = 4; i-- > 0;)
{
data[8 + i] = (char) (uint8_t) cp.tv_nsec % 256;
cp.tv_nsec /= 256;
}
}
MAYBE_UNUSED static int
db_read_cache_entry (const char *db_root, const string_desc_t * id,
struct timespec *request_date,
struct timespec *response_date, bool *invalidated,
string_desc_t * key_id,
string_desc_t * response_header_id,
string_desc_t * response_body_id)
{
string_desc_t file_data = { 0 };
request_date->tv_sec = 0;
request_date->tv_nsec = 0;
response_date->tv_sec = 0;
response_date->tv_nsec = 0;
*invalidated = false;
assert (key_id->_data == NULL);
assert (response_header_id->_data == NULL);
assert (response_body_id->_data == NULL);
key_id->_nbytes = 0;
response_header_id->_nbytes = 0;
response_body_id->_nbytes = 0;
int error = db_read (db_root, id, &file_data);
if (error < 0)
{
goto cleanup;
}
if (file_data._nbytes != 16 + 8 + 4 + 8 + 4 + 32 + 32 + 32 + 1)
{
error = -1;
goto cleanup;
}
if (memcmp (file_data._data, "disfluid c.entry", 16) != 0)
{
error = -1;
goto cleanup;
}
const char *data = file_data._data + 16;
error = parse_timespec (data, request_date);
data += 12;
if (error != 0)
{
goto cleanup;
}
error = parse_timespec (data, response_date);
data += 12;
if (error != 0)
{
goto cleanup;
}
if (ALLOC_N (key_id->_data, 32) < 0)
{
error = -2;
goto cleanup;
}
key_id->_nbytes = 32;
memcpy (key_id->_data, data, 32);
data += 32;
if (ALLOC_N (response_header_id->_data, 32) < 0)
{
error = -2;
goto cleanup;
}
response_header_id->_nbytes = 32;
memcpy (response_header_id->_data, data, 32);
data += 32;
if (ALLOC_N (response_body_id->_data, 32) < 0)
{
error = -2;
goto cleanup;
}
response_body_id->_nbytes = 32;
memcpy (response_body_id->_data, data, 32);
data += 32;
switch (*data)
{
case 0:
break;
case 80:
*invalidated = true;
break;
default:
error = -1;
goto cleanup;
}
cleanup:
if (error != 0)
{
FREE (key_id->_data);
FREE (response_header_id->_data);
FREE (response_body_id->_data);
}
FREE (file_data._data);
return error;
}
MAYBE_UNUSED static int
db_write_cache_entry (const char *db_root, string_desc_t * id,
const struct timespec *request_date,
const struct timespec *response_date, bool invalidated,
const string_desc_t * key_id,
const string_desc_t * response_header_id,
const string_desc_t * response_body_id)
{
char file_data[16 + 8 + 4 + 8 + 4 + 32 + 32 + 32 + 1];
if (key_id->_nbytes != 32 || response_header_id->_nbytes != 32
|| response_body_id->_nbytes != 32)
{
return -1;
}
memcpy (file_data, "disfluid c.entry", 16);
represent_timespec (file_data + 16, request_date);
represent_timespec (file_data + 16 + 12, response_date);
memcpy (file_data + 16 + 12 + 12, key_id->_data, 32);
memcpy (file_data + 16 + 12 + 12 + 32, response_header_id->_data, 32);
memcpy (file_data + 16 + 12 + 12 + 32 + 32, response_body_id->_data, 32);
file_data[16 + 12 + 12 + 32 + 32 + 32] = 0;
if (invalidated)
{
file_data[16 + 12 + 12 + 32 + 32 + 32] = 80;
}
const string_desc_t sd_data = {
._nbytes = sizeof (file_data),
._data = file_data
};
return db_write (db_root, id, &sd_data);
}
#endif /* DISFLUID_DISFLUID_CACHE_ENTRY_INCLUDED */
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