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28 uint32_t magic; /* "PACK" */
31 * Offset to first directory entry in PAK file. It's often
32 * best to store the directories at the end of the file opposed
33 * to the front, since it allows easy insertion without having
34 * to load the entire file into memory again.
41 * A directory, is sort of a "file entry". The concept of
42 * a directory in Quake world is a "file entry/record". This
43 * describes a file (with directories/nested ones too in it's
44 * file name). Hence it can be a file, file with directory, or
45 * file with directories.
54 * Used to get the next token from a string, where the
55 * strings themselfs are seperated by chracters from
56 * `sep`. This is essentially strsep.
58 static char *pak_tree_sep(char **str, const char *sep) {
65 if (*(end = beg + strcspn(beg, sep)))
66 * end++ = '\0'; /* null terminate */
75 * Used to spawn a directory when creating the pak directory structure/
76 * tree. Think of this as mkdir(path, 0700). We just cargo cult our
77 * own because _mkdir on windows is "illegal" for Windows8 Certification
78 * do to the requirement of SECURITY_ATTRIBUTES on everything.
80 static bool pak_tree_spawn(const char *path) {
82 return CreateDirectoryA(path, NULL); /* non-zero on success */
84 return !!(mkdir(path, 0700)); /* zero on success */
89 * When given a string like "a/b/c/d/e/file"
90 * this function will handle the creation of
91 * the directory structure, included nested
94 static void pak_tree_build(const char *entry) {
102 pathsplit = mem_a(56);
103 directory = mem_a(56);
105 strncpy(directory, entry, 56);
106 for (itr = 0; (elements[itr] = pak_tree_sep(&directory, "/")); itr++);
107 for (jtr = 0; jtr < itr - 1; jtr++) {
108 strcat(pathsplit, elements[jtr]);
109 strcat(pathsplit, "/");
111 pak_tree_spawn(pathsplit);
119 pak_directory_t *directories;
125 pak_file_t *pak_open_read(const char *file) {
129 if (!(pak = mem_a(sizeof(pak_file_t))))
132 if (!(pak->handle = file_open(file, "rb"))) {
137 pak->directories = NULL;
138 pak->insert = false; /* read doesn't allow insert */
140 memset (&(pak->header), 0, sizeof(pak_header_t));
141 file_read (&(pak->header), 1, sizeof(pak_header_t), pak->handle);
142 util_endianswap(&(pak->header), 1, sizeof(pak_header_t));
145 * Every PAK file has "PACK" stored as little endian data in the
146 * header. If this data cannot compare (as checked here), it's
147 * probably not a PAK file.
149 if (!(memcmp(&(pak->header.magic), (const void*)"PACK", sizeof(uint32_t)))) {
150 file_close(pak->handle);
156 * Time to read in the directory handles and prepare the directories
157 * vector. We're going to be reading some the file inwards soon.
159 file_seek(pak->handle, pak->header.diroff, SEEK_SET);
162 * Read in all directories from the PAK file. These are considered
163 * to be the "file entries".
165 for (itr = 0; itr < pak->header.dirlen / 64; itr++) {
167 file_read (&dir, 1, sizeof(pak_directory_t), pak->handle);
168 util_endianswap(&dir, 1, sizeof(pak_directory_t));
170 vec_push(pak->directories, dir);
175 pak_file_t *pak_open_write(const char *file) {
178 if (!(pak = mem_a(sizeof(pak_file_t))))
182 * Generate the required directory structure / tree for
183 * writing this PAK file too.
185 pak_tree_build(file);
187 if (!(pak->handle = file_open(file, "wb"))) {
189 * The directory tree that was created, needs to be
190 * removed entierly if we failed to open a file.
192 /* TODO backup directory clean */
197 memset(&(pak->header), 0, sizeof(pak_header_t));
200 * We're in "insert" mode, we need to do things like header
201 * "patching" and writing the directories at the end of the
207 * A valid PAK file contains the magic "PACK" in it's header
208 * stored in little endian format.
210 memcpy(&(pak->header.magic), (const void*)"PACK", sizeof(uint32_t));
213 * We need to write out the header since files will be wrote out to
214 * this even with directory entries, and that not wrote. The header
215 * will need to be patched in later with a file_seek, and overwrite,
216 * we could use offsets and other trickery. This is just easier.
218 file_write(&(pak->header), sizeof(pak_header_t), 1, pak->handle);
223 bool pak_exists(pak_file_t *pak, const char *file, pak_directory_t **dir) {
230 * We could technically use a hashtable here. But I don't think
231 * the lookup complexity is a performance concern. This may be
232 * O(n) lookup. But meh?
234 for (itr = 0; itr < vec_size(pak->directories); itr++) {
235 if (!strcmp(pak->directories[itr].name, file)) {
237 * Store back a pointer to the directory that matches
238 * the request if requested (NULL is not allowed).
241 *dir = &(pak->directories[itr]);
251 * Extraction abilities. These work as you expect them to.
253 bool pak_extract_one(pak_file_t *pak, const char *file) {
254 pak_directory_t *dir = NULL;
255 unsigned char *dat = NULL;
258 if (!pak_exists(pak, file, &dir)) {
262 if (!(dat = (unsigned char *)mem_a(dir->len))) {
267 * Generate the directory structure / tree that will be required
268 * to store the extracted file.
270 pak_tree_build(file);
273 * Now create the file, if this operation fails. Then abort
274 * It shouldn't fail though.
276 if (!(out = file_open(file, "wb"))) {
283 file_seek (pak->handle, dir->pos, SEEK_SET);
284 file_read (dat, 1, dir->len, pak->handle);
287 file_write(dat, 1, dir->len, out);
298 bool pak_extract_all(pak_file_t *pak) {
300 for (itr = 0; itr < vec_size(pak->directories); itr++) {
301 if (!pak_extract_one(pak, pak->directories[itr].name))
309 * Insertion functions (the opposite of extraction). Yes for generating
312 bool pak_insert_one(pak_file_t *pak, const char *file) {
318 * We don't allow insertion on files that already exist within the
319 * pak file. Weird shit can happen if we allow that ;). We also
320 * don't allow insertion if the pak isn't opened in write mode.
322 if (!pak || !file || !pak->insert || pak_exists(pak, file, NULL))
325 if (!(fp = fopen(file, "rb")))
329 * Calculate the total file length, since it will be wrote to
330 * the directory entry, and the actual contents of the file
331 * to the PAK file itself.
333 file_seek(fp, 0, SEEK_END);
335 file_seek(fp, 0, SEEK_SET);
337 dir.pos = ftell(pak->handle);
340 * Allocate some memory for loading in the data that will be
341 * redirected into the PAK file.
343 if (!(dat = (unsigned char *)mem_a(dir.len))) {
348 file_read (dat, dir.len, 1, fp);
350 file_write(dat, dir.len, 1, pak->handle);
356 * Like pak_insert_one, except this collects files in all directories
357 * from a root directory, and inserts them all.
359 bool pak_insert_all(pak_file_t *pak, const char *dir) {
366 if (!(dp = opendir(dir)))
369 while ((dirp = readdir(dp))) {
370 if (!(pak_insert_one(pak, dirp->d_name))) {
380 bool pak_close(pak_file_t *pak) {
387 * In insert mode we need to patch the header, and write
388 * our directory entries at the end of the file.
391 pak->header.dirlen = vec_size(pak->directories) * 64;
392 pak->header.diroff = ftell(pak->handle);
395 file_seek (pak->handle, 0, SEEK_SET);
396 file_write(&(pak->header), sizeof(pak_header_t), 1, pak->handle);
398 /* write directories */
399 file_seek (pak->handle, pak->header.diroff, SEEK_SET);
401 for (itr = 0; itr < vec_size(pak->directories); itr++) {
402 file_write(&(pak->directories[itr]), sizeof(pak_directory_t), 1, pak->handle);
406 vec_free (pak->directories);
407 file_close(pak->handle);