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-rw-r--r--tileserver/tileset.c208
1 files changed, 0 insertions, 208 deletions
diff --git a/tileserver/tileset.c b/tileserver/tileset.c
deleted file mode 100644
index 866125e30..000000000
--- a/tileserver/tileset.c
+++ /dev/null
@@ -1,208 +0,0 @@
-/*
- * tileset.c:
- * Interface to an individual tile set.
- *
- * Copyright (c) 2006 UK Citizens Online Democracy. All rights reserved.
- * Email: chris@mysociety.org; WWW: http://www.mysociety.org/
- *
- */
-
-static const char rcsid[] = "$Id: tileset.c,v 1.6 2006-09-20 16:44:53 chris Exp $";
-
-/*
- * Tile sets are stored in directory trees which contain indices of tile
- * locations to tile IDs, packed archives of tile images, and indices of where
- * each tile image lives in the corresponding packed file. Tile IDs are SHA1
- * digests of the tile contents, enabling efficient storage in the presence of
- * repeated tiles.
- *
- * Note that this doesn't have attractive properties for locality of reference.
- * That will need fixing if performance under the current scheme is not
- * acceptable.
- */
-
-#include <stdbool.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-
-#include "cdb.h"
-#include "tileset.h"
-#include "util.h"
-
-#define TILEID_LEN 20
-
-struct tileset {
- char *t_path, *t_pathbuf;
- cdb t_tileid_idx;
- /* Tile IDs are stored in the tile ID database in N-by-N square blocks,
- * so that the tile ID for (X, Y) is obtained by getting the block for
- * (X / N, Y / N) and looking up (X, Y) within it. The blocking factor is
- * (hopefully!) chosen to be about a disk block in size. It is stored in
- * the tile ID database. Rather than allocating a specific tile ID for a
- * tile which is not present, each information block is preceded by a
- * coverage bitmap. */
- unsigned t_blocking;
- bool t_first;
- unsigned t_x, t_y;
- cdb_datum t_block;
- /* File pointer open on an image file and the name of the file it's open
- * on. */
- char *t_imgfile;
- FILE *t_fpimg;
-};
-
-
-/* tileset_open PATH
- * Open the tileset at PATH, returning a tileset object on success or NULL on
- * failure. */
-tileset tileset_open(const char *path) {
- struct tileset *T, Tz = {0};
- cdb_datum d = NULL;
- char *s;
- int i;
-
- T = xmalloc(sizeof *T);
- *T = Tz;
-
- T->t_first = 1;
- T->t_path = xstrdup(path);
- T->t_pathbuf = xmalloc(strlen(path) + sizeof "/tiles/a/b/c/tiles.cdb");
-
- /* Open the tile ID index. */
- sprintf(T->t_pathbuf, "%s/index.cdb", T->t_path);
- if (!(T->t_tileid_idx = cdb_open(T->t_pathbuf)))
- goto fail;
-
- /* get blocking factor */
- if (!(d = cdb_get_string(T->t_tileid_idx, "blocking")))
- goto fail;
- s = (char*)d->cd_buf;
- if (!(i = atoi(s)) || i < 0)
- goto fail;
- T->t_blocking = (unsigned)i;
-
- cdb_datum_free(d);
-
- return T;
-
-fail:
- tileset_close(T);
- if (d) cdb_datum_free(d);
- return NULL;
-}
-
-/* tileset_close T
- * Free resources associated with T. */
-void tileset_close(tileset T) {
- if (!T) return;
- cdb_close(T->t_tileid_idx);
- xfree(T->t_path);
- xfree(T->t_pathbuf);
- xfree(T);
-}
-
-/* tileset_path T
- * Return the path used to open T. */
-char *tileset_path(tileset T) {
- return T->t_path;
-}
-
-static size_t blockmap_bitmap_len(const unsigned blocking) {
- return (blocking * blocking + 8) / 8;
-}
-
-static size_t blockmap_len(const unsigned blocking) {
- size_t l;
- /* Bitmap of null tiles. */
- l = blockmap_bitmap_len(blocking);
- /* Tile IDs themselves */
- l += blocking * blocking * TILEID_LEN;
- return l;
-}
-
-/* tileset_get_tileid T X Y ID
- * Write into ID the tile ID of the tile at (X, Y) in T, returning true on
- * success or false on failure. */
-bool tileset_get_tileid(tileset T, const unsigned x, const unsigned y,
- uint8_t *id) {
- unsigned x2, y2, off, off0;
- uint8_t *b;
-
- if (T->t_first || T->t_x != x || T->t_y != y) {
- /* Grab block from database. */
- char buf[32];
-
- T->t_first = 0;
- if (T->t_block) cdb_datum_free(T->t_block);
-
- sprintf(buf, "%u,%u", x / T->t_blocking, y / T->t_blocking);
- if (!(T->t_block = cdb_get_string(T->t_tileid_idx, buf)))
- return 0;
- }
-
- if (T->t_block->cd_len != blockmap_len(T->t_blocking))
- return 0;
- /* XXX also report bogus ID block */
-
- b = (uint8_t*)T->t_block->cd_buf;
-
- x2 = x % T->t_blocking;
- y2 = y % T->t_blocking;
- off = (x2 + y2 * T->t_blocking);
-
- /* For a tile not present the corresponding bit in the bitmap is set. */
- if (b[off >> 3] & (1 << (off & 7)))
- return 0;
-
- off0 = blockmap_bitmap_len(T->t_blocking);
- memcpy(id, b + off0 + off * TILEID_LEN, TILEID_LEN);
-
- return 1;
-}
-
-/* tileset_get_tile T ID LEN
- * Retrieve the tile identified by ID, writing its length into *LEN and
- * returning a malloced buffer containing its contents on success, or returning
- * NULL on failure. */
-void *tileset_get_tile(tileset T, const uint8_t *id, size_t *len) {
- cdb idx = NULL;
- cdb_datum d = NULL;
- void *ret = NULL;
- unsigned off;
- FILE *fp = NULL;
-
- sprintf(T->t_pathbuf, "%s/tiles/%x/%x/%x/tiles.cdb",
- T->t_path, (unsigned)(id[0] >> 4),
- (unsigned)(id[0] & 0xf), (unsigned)(id[1] >> 4));
- if (!(idx = cdb_open(T->t_pathbuf)))
- return NULL;
- /* also maybe report bogus index */
-
- if (!(d = cdb_get_buf(idx, id, TILEID_LEN)))
- goto fail;
-
- if (2 != sscanf((char*)d->cd_buf, "%x:%x", &off, len))
- goto fail;
-
- sprintf(T->t_pathbuf, "%s/tiles/%x/%x/%x/tiles",
- T->t_path, (unsigned)(id[0] >> 4),
- (unsigned)(id[0] & 0xf), (unsigned)(id[1] >> 4));
- if (!(fp = fopen(T->t_pathbuf, "rb")))
- goto fail;
- else if (-1 == fseek(fp, off, SEEK_SET))
- goto fail;
-
- ret = xmalloc(*len);
- if (*len != fread(ret, 1, *len, fp)) {
- xfree(ret);
- goto fail;
- }
-
-fail:
- if (idx) cdb_close(idx);
- if (d) cdb_datum_free(d);
- if (fp) fclose(fp);
- return ret;
-}
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