denyhosts/ip2region/xdb_searcher.c

403 lines
11 KiB
C
Raw Normal View History

// Copyright 2022 The Ip2Region Authors. All rights reserved.
// Use of this source code is governed by a Apache2.0-style
// license that can be found in the LICENSE file.
// ---
// @Author Lion <chenxin619315@gmail.com>
// @Date 2022/06/27
#include "sys/time.h"
#include "xdb_searcher.h"
// internal function prototype define
XDB_PRIVATE(int) read(xdb_searcher_t *, long offset, char *, size_t length);
XDB_PRIVATE(int) xdb_new_base(xdb_searcher_t *xdb, const char *db_path, const xdb_vector_index_t *v_index, const xdb_content_t *c_buffer) {
memset(xdb, 0x00, sizeof(xdb_searcher_t));
// check the content buffer first
if (c_buffer != NULL) {
xdb->v_index = NULL;
xdb->content = c_buffer;
return 0;
}
// open the xdb binary file
FILE *handle = fopen(db_path, "rb");
if (handle == NULL) {
return 1;
}
xdb->handle = handle;
xdb->v_index = v_index;
return 0;
}
// xdb searcher new api define
XDB_PUBLIC(int) xdb_new_with_file_only(xdb_searcher_t *xdb, const char *db_path) {
return xdb_new_base(xdb, db_path, NULL, NULL);
}
XDB_PUBLIC(int) xdb_new_with_vector_index(xdb_searcher_t *xdb, const char *db_path, const xdb_vector_index_t *v_index) {
return xdb_new_base(xdb, db_path, v_index, NULL);
}
XDB_PUBLIC(int) xdb_new_with_buffer(xdb_searcher_t *xdb, const xdb_content_t *c_buffer) {
return xdb_new_base(xdb, NULL, NULL, c_buffer);
}
XDB_PUBLIC(void) xdb_close(void *ptr) {
xdb_searcher_t *xdb = (xdb_searcher_t *) ptr;
if (xdb->handle != NULL) {
fclose(xdb->handle);
xdb->handle = NULL;
}
}
// --- xdb searcher search api define
XDB_PUBLIC(int) xdb_search_by_string(xdb_searcher_t *xdb, const char *str_ip, char *region_buffer, size_t length) {
unsigned int ip = 0;
int errcode = xdb_check_ip(str_ip, &ip);
if (errcode != 0) {
return 10 + errcode;
} else {
return xdb_search(xdb, ip, region_buffer, length);
}
}
XDB_PUBLIC(int) xdb_search(xdb_searcher_t *xdb, unsigned int ip, char *region_buffer, size_t length) {
int il0, il1, idx, err, l, h, m, data_len;
unsigned int s_ptr, e_ptr, p, sip, eip, data_ptr;
char vector_buffer[xdb_vector_index_size], segment_buffer[xdb_segment_index_size];
// reset the io counter
xdb->io_count = 0;
// locate the segment index block based on the vector index
il0 = ((int) (ip >> 24)) & 0xFF;
il1 = ((int) (ip >> 16)) & 0xFF;
idx = il0 * xdb_vector_index_cols * xdb_vector_index_size + il1 * xdb_vector_index_size;
if (xdb->v_index != NULL) {
s_ptr = xdb_get_uint(xdb->v_index->buffer, idx);
e_ptr = xdb_get_uint(xdb->v_index->buffer, idx + 4);
} else if (xdb->content != NULL) {
s_ptr = xdb_get_uint(xdb->content->buffer, xdb_header_info_length + idx);
e_ptr = xdb_get_uint(xdb->content->buffer, xdb_header_info_length + idx + 4);
} else {
err = read(xdb, xdb_header_info_length + idx, vector_buffer, sizeof(vector_buffer));
if (err != 0) {
return 10 + err;
}
s_ptr = xdb_get_uint(vector_buffer, 0);
e_ptr = xdb_get_uint(vector_buffer, 4);
}
// printf("s_ptr=%u, e_ptr=%u\n", s_ptr, e_ptr);
// binary search to get the final region info
data_len = 0, data_ptr = 0;
l = 0, h = ((int) (e_ptr - s_ptr)) / xdb_segment_index_size;
while (l <= h) {
m = (l + h) >> 1;
p = s_ptr + m * xdb_segment_index_size;
// read the segment index item
err = read(xdb, p, segment_buffer, sizeof(segment_buffer));
if (err != 0) {
return 20 + err;
}
// decode the data fields as needed
sip = xdb_get_uint(segment_buffer, 0);
if (ip < sip) {
h = m - 1;
} else {
eip = xdb_get_uint(segment_buffer, 4);
if (ip > eip) {
l = m + 1;
} else {
data_len = xdb_get_ushort(segment_buffer, 8);
data_ptr = xdb_get_uint(segment_buffer, 10);
break;
}
}
}
// printf("data_len=%u, data_ptr=%u\n", data_len, data_ptr);
if (data_len == 0) {
region_buffer[0] = '\0';
return 0;
}
// buffer length checking
if (data_len >= length) {
return 1;
}
err = read(xdb, data_ptr, region_buffer, data_len);
if (err != 0) {
return 30 + err;
}
// auto append a NULL-end
region_buffer[data_len] = '\0';
return 0;
}
XDB_PRIVATE(int) read(xdb_searcher_t *xdb, long offset, char *buffer, size_t length) {
// check the xdb content cache first
if (xdb->content != NULL) {
memcpy(buffer, xdb->content->buffer + offset, length);
return 0;
}
// seek to the offset
if (fseek(xdb->handle, offset, SEEK_SET) == -1) {
return 1;
}
xdb->io_count++;
if (fread(buffer, 1, length, xdb->handle) != length) {
return 2;
}
return 0;
}
XDB_PUBLIC(int) xdb_get_io_count(xdb_searcher_t *xdb) {
return xdb->io_count;
}
// --- buffer load util functions
XDB_PUBLIC(xdb_header_t *) xdb_load_header(FILE *handle) {
xdb_header_t *header;
unsigned int size = xdb_header_info_length;
// entry alloc
header = (xdb_header_t *) xdb_malloc(sizeof(xdb_header_t));
if (header == NULL) {
return NULL;
}
if (fseek(handle, 0, SEEK_SET) == -1) {
xdb_free(header);
return NULL;
}
if (fread(header->buffer, 1,size, handle) != size) {
xdb_free(header);
return NULL;
}
// fill the fields
header->length = size;
header->version = (unsigned short) xdb_get_ushort(header->buffer, 0);
header->index_policy = (unsigned short) xdb_get_ushort(header->buffer, 2);
header->created_at = xdb_get_uint(header->buffer, 4);
header->start_index_ptr = xdb_get_uint(header->buffer, 8);
header->end_index_ptr = xdb_get_uint(header->buffer,12);
return header;
}
XDB_PUBLIC(xdb_header_t *) xdb_load_header_from_file(const char *db_path) {
xdb_header_t *header;
FILE *handle = fopen(db_path, "rb");
if (handle == NULL) {
return NULL;
}
header = xdb_load_header(handle);
fclose(handle);
return header;
}
XDB_PUBLIC(void) xdb_close_header(void *ptr) {
xdb_header_t *header = (xdb_header_t *) ptr;
if (header->length > 0) {
header->length = 0;
xdb_free(header);
}
}
// --- vector index
XDB_PUBLIC(xdb_vector_index_t *) xdb_load_vector_index(FILE *handle) {
xdb_vector_index_t *v_index;
unsigned int size = xdb_vector_index_length;
// seek to the vector index offset
if (fseek(handle, xdb_header_info_length, SEEK_SET) == -1) {
return NULL;
}
// do the buffer read
v_index = (xdb_vector_index_t *) xdb_malloc(sizeof(xdb_vector_index_t));
if (v_index == NULL) {
return NULL;
}
v_index->length = size;
if (fread(v_index->buffer, 1, size, handle) != size) {
xdb_free(v_index);
return NULL;
}
return v_index;
}
XDB_PUBLIC(xdb_vector_index_t *) xdb_load_vector_index_from_file(const char *db_path) {
xdb_vector_index_t *v_index;
FILE *handle = fopen(db_path, "rb");
if (handle == NULL) {
return NULL;
}
v_index = xdb_load_vector_index(handle);
fclose(handle);
return v_index;
}
XDB_PUBLIC(void) xdb_close_vector_index(void *ptr) {
xdb_vector_index_t *v_index = (xdb_vector_index_t *) ptr;
if (v_index->length > 0) {
v_index->length = 0;
xdb_free(v_index);
}
}
// --- content buffer
XDB_PUBLIC(xdb_content_t *) xdb_load_content(FILE *handle) {
unsigned int size;
xdb_content_t *content;
// determine the file size
if (fseek(handle, 0, SEEK_END) == -1) {
return NULL;
}
size = (unsigned int) ftell(handle);
if (fseek(handle, 0, SEEK_SET) == -1) {
return NULL;
}
// do the file read
content = (xdb_content_t *) xdb_malloc(sizeof(xdb_content_t));
if (content == NULL) {
return NULL;
}
// do the buffer alloc
content->buffer = (char *) xdb_malloc(size);
if (content->buffer == NULL) {
xdb_free(content);
return NULL;
}
// read the content into the buffer
content->length = size;
if (fread(content->buffer, 1, size, handle) != size) {
xdb_free(content);
return NULL;
}
return content;
}
XDB_PUBLIC(xdb_content_t *) xdb_load_content_from_file(const char *db_path) {
xdb_content_t *content;
FILE *handle = fopen(db_path, "rb");
if (handle == NULL) {
return NULL;
}
content = xdb_load_content(handle);
fclose(handle);
return content;
}
XDB_PUBLIC(void) xdb_close_content(void *ptr) {
xdb_content_t *content = (xdb_content_t *) ptr;
if (content->length > 0) {
content->length = 0;
xdb_free(content->buffer);
content->buffer = NULL;
xdb_free(content);
}
}
// --- End
// get unsigned long (4bytes) from a specified buffer start from the specified offset
XDB_PUBLIC(unsigned int) xdb_get_uint(const char *buffer, int offset) {
return (
((buffer[offset ]) & 0x000000FF) |
((buffer[offset+1] << 8) & 0x0000FF00) |
((buffer[offset+2] << 16) & 0x00FF0000) |
((buffer[offset+3] << 24) & 0xFF000000)
);
}
// get unsigned short (2bytes) from a specified buffer start from the specified offset
XDB_PUBLIC(int) xdb_get_ushort(const char *buffer, int offset) {
return (
((buffer[offset ]) & 0x000000FF) |
((buffer[offset+1] << 8) & 0x0000FF00)
);
}
// string ip to unsigned int
static int shiftIndex[4] = {24, 16, 8, 0};
XDB_PUBLIC(int) xdb_check_ip(const char *src_ip, unsigned int *dst_ip) {
char c;
int i, n, ip = 0;
const char *ptr = src_ip;
for (i = 0; i < 4; i++) {
n = 0;
while (1) {
c = *ptr;
ptr++;
if (c >= '0' && c <= '9') {
n *= 10;
n += c - '0';
} else if ((i < 3 && c == '.') || i == 3) {
// stopping at the '.' but ignore the tailing chars
// after the 3rd one (auto clean the tailing none-integer ?).
break;
} else {
return 1;
}
}
if (n > 0xFF) {
return 2;
}
ip |= (n << shiftIndex[i]);
}
*dst_ip = ip;
return 0;
}
// unsigned int ip to string ip
XDB_PUBLIC(void) xdb_long2ip(unsigned int ip, char *buffer) {
sprintf(buffer, "%d.%d.%d.%d", (ip >> 24) & 0xFF, (ip >> 16) & 0xFF, (ip >> 8) & 0xFF, ip & 0xFF);
}
// get the middle ip of a and b
XDB_PUBLIC(unsigned int) xdb_mip(unsigned long a, unsigned long b) {
return (unsigned int) ((a + b) >> 1);
}
XDB_PUBLIC(long) xdb_now() {
struct timeval c_time;
gettimeofday(&c_time, NULL);
return c_time.tv_sec * (int)1e6 + c_time.tv_usec;
}