archive-zip: mark text files in archives
[git] / archive-zip.c
1 /*
2  * Copyright (c) 2006 Rene Scharfe
3  */
4 #include "cache.h"
5 #include "archive.h"
6 #include "streaming.h"
7 #include "utf8.h"
8 #include "userdiff.h"
9 #include "xdiff-interface.h"
10
11 static int zip_date;
12 static int zip_time;
13
14 static unsigned char *zip_dir;
15 static unsigned int zip_dir_size;
16
17 static unsigned int zip_offset;
18 static unsigned int zip_dir_offset;
19 static unsigned int zip_dir_entries;
20
21 #define ZIP_DIRECTORY_MIN_SIZE  (1024 * 1024)
22 #define ZIP_STREAM      (1 <<  3)
23 #define ZIP_UTF8        (1 << 11)
24
25 struct zip_local_header {
26         unsigned char magic[4];
27         unsigned char version[2];
28         unsigned char flags[2];
29         unsigned char compression_method[2];
30         unsigned char mtime[2];
31         unsigned char mdate[2];
32         unsigned char crc32[4];
33         unsigned char compressed_size[4];
34         unsigned char size[4];
35         unsigned char filename_length[2];
36         unsigned char extra_length[2];
37         unsigned char _end[1];
38 };
39
40 struct zip_data_desc {
41         unsigned char magic[4];
42         unsigned char crc32[4];
43         unsigned char compressed_size[4];
44         unsigned char size[4];
45         unsigned char _end[1];
46 };
47
48 struct zip_dir_header {
49         unsigned char magic[4];
50         unsigned char creator_version[2];
51         unsigned char version[2];
52         unsigned char flags[2];
53         unsigned char compression_method[2];
54         unsigned char mtime[2];
55         unsigned char mdate[2];
56         unsigned char crc32[4];
57         unsigned char compressed_size[4];
58         unsigned char size[4];
59         unsigned char filename_length[2];
60         unsigned char extra_length[2];
61         unsigned char comment_length[2];
62         unsigned char disk[2];
63         unsigned char attr1[2];
64         unsigned char attr2[4];
65         unsigned char offset[4];
66         unsigned char _end[1];
67 };
68
69 struct zip_dir_trailer {
70         unsigned char magic[4];
71         unsigned char disk[2];
72         unsigned char directory_start_disk[2];
73         unsigned char entries_on_this_disk[2];
74         unsigned char entries[2];
75         unsigned char size[4];
76         unsigned char offset[4];
77         unsigned char comment_length[2];
78         unsigned char _end[1];
79 };
80
81 struct zip_extra_mtime {
82         unsigned char magic[2];
83         unsigned char extra_size[2];
84         unsigned char flags[1];
85         unsigned char mtime[4];
86         unsigned char _end[1];
87 };
88
89 /*
90  * On ARM, padding is added at the end of the struct, so a simple
91  * sizeof(struct ...) reports two bytes more than the payload size
92  * we're interested in.
93  */
94 #define ZIP_LOCAL_HEADER_SIZE   offsetof(struct zip_local_header, _end)
95 #define ZIP_DATA_DESC_SIZE      offsetof(struct zip_data_desc, _end)
96 #define ZIP_DIR_HEADER_SIZE     offsetof(struct zip_dir_header, _end)
97 #define ZIP_DIR_TRAILER_SIZE    offsetof(struct zip_dir_trailer, _end)
98 #define ZIP_EXTRA_MTIME_SIZE    offsetof(struct zip_extra_mtime, _end)
99 #define ZIP_EXTRA_MTIME_PAYLOAD_SIZE \
100         (ZIP_EXTRA_MTIME_SIZE - offsetof(struct zip_extra_mtime, flags))
101
102 static void copy_le16(unsigned char *dest, unsigned int n)
103 {
104         dest[0] = 0xff & n;
105         dest[1] = 0xff & (n >> 010);
106 }
107
108 static void copy_le32(unsigned char *dest, unsigned int n)
109 {
110         dest[0] = 0xff & n;
111         dest[1] = 0xff & (n >> 010);
112         dest[2] = 0xff & (n >> 020);
113         dest[3] = 0xff & (n >> 030);
114 }
115
116 static void *zlib_deflate_raw(void *data, unsigned long size,
117                               int compression_level,
118                               unsigned long *compressed_size)
119 {
120         git_zstream stream;
121         unsigned long maxsize;
122         void *buffer;
123         int result;
124
125         memset(&stream, 0, sizeof(stream));
126         git_deflate_init_raw(&stream, compression_level);
127         maxsize = git_deflate_bound(&stream, size);
128         buffer = xmalloc(maxsize);
129
130         stream.next_in = data;
131         stream.avail_in = size;
132         stream.next_out = buffer;
133         stream.avail_out = maxsize;
134
135         do {
136                 result = git_deflate(&stream, Z_FINISH);
137         } while (result == Z_OK);
138
139         if (result != Z_STREAM_END) {
140                 free(buffer);
141                 return NULL;
142         }
143
144         git_deflate_end(&stream);
145         *compressed_size = stream.total_out;
146
147         return buffer;
148 }
149
150 static void write_zip_data_desc(unsigned long size,
151                                 unsigned long compressed_size,
152                                 unsigned long crc)
153 {
154         struct zip_data_desc trailer;
155
156         copy_le32(trailer.magic, 0x08074b50);
157         copy_le32(trailer.crc32, crc);
158         copy_le32(trailer.compressed_size, compressed_size);
159         copy_le32(trailer.size, size);
160         write_or_die(1, &trailer, ZIP_DATA_DESC_SIZE);
161 }
162
163 static void set_zip_dir_data_desc(struct zip_dir_header *header,
164                                   unsigned long size,
165                                   unsigned long compressed_size,
166                                   unsigned long crc)
167 {
168         copy_le32(header->crc32, crc);
169         copy_le32(header->compressed_size, compressed_size);
170         copy_le32(header->size, size);
171 }
172
173 static void set_zip_header_data_desc(struct zip_local_header *header,
174                                      unsigned long size,
175                                      unsigned long compressed_size,
176                                      unsigned long crc)
177 {
178         copy_le32(header->crc32, crc);
179         copy_le32(header->compressed_size, compressed_size);
180         copy_le32(header->size, size);
181 }
182
183 static int has_only_ascii(const char *s)
184 {
185         for (;;) {
186                 int c = *s++;
187                 if (c == '\0')
188                         return 1;
189                 if (!isascii(c))
190                         return 0;
191         }
192 }
193
194 static int entry_is_binary(const char *path, const void *buffer, size_t size)
195 {
196         struct userdiff_driver *driver = userdiff_find_by_path(path);
197         if (!driver)
198                 driver = userdiff_find_by_name("default");
199         if (driver->binary != -1)
200                 return driver->binary;
201         return buffer_is_binary(buffer, size);
202 }
203
204 #define STREAM_BUFFER_SIZE (1024 * 16)
205
206 static int write_zip_entry(struct archiver_args *args,
207                            const unsigned char *sha1,
208                            const char *path, size_t pathlen,
209                            unsigned int mode)
210 {
211         struct zip_local_header header;
212         struct zip_dir_header dirent;
213         struct zip_extra_mtime extra;
214         unsigned long attr2;
215         unsigned long compressed_size;
216         unsigned long crc;
217         unsigned long direntsize;
218         int method;
219         unsigned char *out;
220         void *deflated = NULL;
221         void *buffer;
222         struct git_istream *stream = NULL;
223         unsigned long flags = 0;
224         unsigned long size;
225         int is_binary = -1;
226         const char *path_without_prefix = path + args->baselen;
227
228         crc = crc32(0, NULL, 0);
229
230         if (!has_only_ascii(path)) {
231                 if (is_utf8(path))
232                         flags |= ZIP_UTF8;
233                 else
234                         warning("Path is not valid UTF-8: %s", path);
235         }
236
237         if (pathlen > 0xffff) {
238                 return error("path too long (%d chars, SHA1: %s): %s",
239                                 (int)pathlen, sha1_to_hex(sha1), path);
240         }
241
242         if (S_ISDIR(mode) || S_ISGITLINK(mode)) {
243                 method = 0;
244                 attr2 = 16;
245                 out = NULL;
246                 size = 0;
247                 compressed_size = 0;
248                 buffer = NULL;
249         } else if (S_ISREG(mode) || S_ISLNK(mode)) {
250                 enum object_type type = sha1_object_info(sha1, &size);
251
252                 method = 0;
253                 attr2 = S_ISLNK(mode) ? ((mode | 0777) << 16) :
254                         (mode & 0111) ? ((mode) << 16) : 0;
255                 if (S_ISREG(mode) && args->compression_level != 0 && size > 0)
256                         method = 8;
257
258                 if (S_ISREG(mode) && type == OBJ_BLOB && !args->convert &&
259                     size > big_file_threshold) {
260                         stream = open_istream(sha1, &type, &size, NULL);
261                         if (!stream)
262                                 return error("cannot stream blob %s",
263                                              sha1_to_hex(sha1));
264                         flags |= ZIP_STREAM;
265                         out = buffer = NULL;
266                 } else {
267                         buffer = sha1_file_to_archive(args, path, sha1, mode,
268                                                       &type, &size);
269                         if (!buffer)
270                                 return error("cannot read %s",
271                                              sha1_to_hex(sha1));
272                         crc = crc32(crc, buffer, size);
273                         is_binary = entry_is_binary(path_without_prefix,
274                                                     buffer, size);
275                         out = buffer;
276                 }
277                 compressed_size = (method == 0) ? size : 0;
278         } else {
279                 return error("unsupported file mode: 0%o (SHA1: %s)", mode,
280                                 sha1_to_hex(sha1));
281         }
282
283         if (buffer && method == 8) {
284                 out = deflated = zlib_deflate_raw(buffer, size,
285                                                   args->compression_level,
286                                                   &compressed_size);
287                 if (!out || compressed_size >= size) {
288                         out = buffer;
289                         method = 0;
290                         compressed_size = size;
291                 }
292         }
293
294         copy_le16(extra.magic, 0x5455);
295         copy_le16(extra.extra_size, ZIP_EXTRA_MTIME_PAYLOAD_SIZE);
296         extra.flags[0] = 1;     /* just mtime */
297         copy_le32(extra.mtime, args->time);
298
299         /* make sure we have enough free space in the dictionary */
300         direntsize = ZIP_DIR_HEADER_SIZE + pathlen + ZIP_EXTRA_MTIME_SIZE;
301         while (zip_dir_size < zip_dir_offset + direntsize) {
302                 zip_dir_size += ZIP_DIRECTORY_MIN_SIZE;
303                 zip_dir = xrealloc(zip_dir, zip_dir_size);
304         }
305
306         copy_le32(dirent.magic, 0x02014b50);
307         copy_le16(dirent.creator_version,
308                 S_ISLNK(mode) || (S_ISREG(mode) && (mode & 0111)) ? 0x0317 : 0);
309         copy_le16(dirent.version, 10);
310         copy_le16(dirent.flags, flags);
311         copy_le16(dirent.compression_method, method);
312         copy_le16(dirent.mtime, zip_time);
313         copy_le16(dirent.mdate, zip_date);
314         set_zip_dir_data_desc(&dirent, size, compressed_size, crc);
315         copy_le16(dirent.filename_length, pathlen);
316         copy_le16(dirent.extra_length, ZIP_EXTRA_MTIME_SIZE);
317         copy_le16(dirent.comment_length, 0);
318         copy_le16(dirent.disk, 0);
319         copy_le32(dirent.attr2, attr2);
320         copy_le32(dirent.offset, zip_offset);
321
322         copy_le32(header.magic, 0x04034b50);
323         copy_le16(header.version, 10);
324         copy_le16(header.flags, flags);
325         copy_le16(header.compression_method, method);
326         copy_le16(header.mtime, zip_time);
327         copy_le16(header.mdate, zip_date);
328         set_zip_header_data_desc(&header, size, compressed_size, crc);
329         copy_le16(header.filename_length, pathlen);
330         copy_le16(header.extra_length, ZIP_EXTRA_MTIME_SIZE);
331         write_or_die(1, &header, ZIP_LOCAL_HEADER_SIZE);
332         zip_offset += ZIP_LOCAL_HEADER_SIZE;
333         write_or_die(1, path, pathlen);
334         zip_offset += pathlen;
335         write_or_die(1, &extra, ZIP_EXTRA_MTIME_SIZE);
336         zip_offset += ZIP_EXTRA_MTIME_SIZE;
337         if (stream && method == 0) {
338                 unsigned char buf[STREAM_BUFFER_SIZE];
339                 ssize_t readlen;
340
341                 for (;;) {
342                         readlen = read_istream(stream, buf, sizeof(buf));
343                         if (readlen <= 0)
344                                 break;
345                         crc = crc32(crc, buf, readlen);
346                         if (is_binary == -1)
347                                 is_binary = entry_is_binary(path_without_prefix,
348                                                             buf, readlen);
349                         write_or_die(1, buf, readlen);
350                 }
351                 close_istream(stream);
352                 if (readlen)
353                         return readlen;
354
355                 compressed_size = size;
356                 zip_offset += compressed_size;
357
358                 write_zip_data_desc(size, compressed_size, crc);
359                 zip_offset += ZIP_DATA_DESC_SIZE;
360
361                 set_zip_dir_data_desc(&dirent, size, compressed_size, crc);
362         } else if (stream && method == 8) {
363                 unsigned char buf[STREAM_BUFFER_SIZE];
364                 ssize_t readlen;
365                 git_zstream zstream;
366                 int result;
367                 size_t out_len;
368                 unsigned char compressed[STREAM_BUFFER_SIZE * 2];
369
370                 memset(&zstream, 0, sizeof(zstream));
371                 git_deflate_init_raw(&zstream, args->compression_level);
372
373                 compressed_size = 0;
374                 zstream.next_out = compressed;
375                 zstream.avail_out = sizeof(compressed);
376
377                 for (;;) {
378                         readlen = read_istream(stream, buf, sizeof(buf));
379                         if (readlen <= 0)
380                                 break;
381                         crc = crc32(crc, buf, readlen);
382                         if (is_binary == -1)
383                                 is_binary = entry_is_binary(path_without_prefix,
384                                                             buf, readlen);
385
386                         zstream.next_in = buf;
387                         zstream.avail_in = readlen;
388                         result = git_deflate(&zstream, 0);
389                         if (result != Z_OK)
390                                 die("deflate error (%d)", result);
391                         out_len = zstream.next_out - compressed;
392
393                         if (out_len > 0) {
394                                 write_or_die(1, compressed, out_len);
395                                 compressed_size += out_len;
396                                 zstream.next_out = compressed;
397                                 zstream.avail_out = sizeof(compressed);
398                         }
399
400                 }
401                 close_istream(stream);
402                 if (readlen)
403                         return readlen;
404
405                 zstream.next_in = buf;
406                 zstream.avail_in = 0;
407                 result = git_deflate(&zstream, Z_FINISH);
408                 if (result != Z_STREAM_END)
409                         die("deflate error (%d)", result);
410
411                 git_deflate_end(&zstream);
412                 out_len = zstream.next_out - compressed;
413                 write_or_die(1, compressed, out_len);
414                 compressed_size += out_len;
415                 zip_offset += compressed_size;
416
417                 write_zip_data_desc(size, compressed_size, crc);
418                 zip_offset += ZIP_DATA_DESC_SIZE;
419
420                 set_zip_dir_data_desc(&dirent, size, compressed_size, crc);
421         } else if (compressed_size > 0) {
422                 write_or_die(1, out, compressed_size);
423                 zip_offset += compressed_size;
424         }
425
426         free(deflated);
427         free(buffer);
428
429         copy_le16(dirent.attr1, !is_binary);
430
431         memcpy(zip_dir + zip_dir_offset, &dirent, ZIP_DIR_HEADER_SIZE);
432         zip_dir_offset += ZIP_DIR_HEADER_SIZE;
433         memcpy(zip_dir + zip_dir_offset, path, pathlen);
434         zip_dir_offset += pathlen;
435         memcpy(zip_dir + zip_dir_offset, &extra, ZIP_EXTRA_MTIME_SIZE);
436         zip_dir_offset += ZIP_EXTRA_MTIME_SIZE;
437         zip_dir_entries++;
438
439         return 0;
440 }
441
442 static void write_zip_trailer(const unsigned char *sha1)
443 {
444         struct zip_dir_trailer trailer;
445
446         copy_le32(trailer.magic, 0x06054b50);
447         copy_le16(trailer.disk, 0);
448         copy_le16(trailer.directory_start_disk, 0);
449         copy_le16(trailer.entries_on_this_disk, zip_dir_entries);
450         copy_le16(trailer.entries, zip_dir_entries);
451         copy_le32(trailer.size, zip_dir_offset);
452         copy_le32(trailer.offset, zip_offset);
453         copy_le16(trailer.comment_length, sha1 ? 40 : 0);
454
455         write_or_die(1, zip_dir, zip_dir_offset);
456         write_or_die(1, &trailer, ZIP_DIR_TRAILER_SIZE);
457         if (sha1)
458                 write_or_die(1, sha1_to_hex(sha1), 40);
459 }
460
461 static void dos_time(time_t *time, int *dos_date, int *dos_time)
462 {
463         struct tm *t = localtime(time);
464
465         *dos_date = t->tm_mday + (t->tm_mon + 1) * 32 +
466                     (t->tm_year + 1900 - 1980) * 512;
467         *dos_time = t->tm_sec / 2 + t->tm_min * 32 + t->tm_hour * 2048;
468 }
469
470 static int write_zip_archive(const struct archiver *ar,
471                              struct archiver_args *args)
472 {
473         int err;
474
475         dos_time(&args->time, &zip_date, &zip_time);
476
477         zip_dir = xmalloc(ZIP_DIRECTORY_MIN_SIZE);
478         zip_dir_size = ZIP_DIRECTORY_MIN_SIZE;
479
480         err = write_archive_entries(args, write_zip_entry);
481         if (!err)
482                 write_zip_trailer(args->commit_sha1);
483
484         free(zip_dir);
485
486         return err;
487 }
488
489 static struct archiver zip_archiver = {
490         "zip",
491         write_zip_archive,
492         ARCHIVER_WANT_COMPRESSION_LEVELS|ARCHIVER_REMOTE
493 };
494
495 void init_zip_archiver(void)
496 {
497         register_archiver(&zip_archiver);
498 }