gitweb: use new Git::Repo API, and add optional caching
[git/gitweb-caching.git] / archive-zip.c
blobcf285044e3576d0127c3215cb1253443d67517dc
1 /*
2 * Copyright (c) 2006 Rene Scharfe
3 */
4 #include "cache.h"
5 #include "archive.h"
7 static int zip_date;
8 static int zip_time;
10 static unsigned char *zip_dir;
11 static unsigned int zip_dir_size;
13 static unsigned int zip_offset;
14 static unsigned int zip_dir_offset;
15 static unsigned int zip_dir_entries;
17 #define ZIP_DIRECTORY_MIN_SIZE (1024 * 1024)
19 struct zip_local_header {
20 unsigned char magic[4];
21 unsigned char version[2];
22 unsigned char flags[2];
23 unsigned char compression_method[2];
24 unsigned char mtime[2];
25 unsigned char mdate[2];
26 unsigned char crc32[4];
27 unsigned char compressed_size[4];
28 unsigned char size[4];
29 unsigned char filename_length[2];
30 unsigned char extra_length[2];
31 unsigned char _end[1];
34 struct zip_dir_header {
35 unsigned char magic[4];
36 unsigned char creator_version[2];
37 unsigned char version[2];
38 unsigned char flags[2];
39 unsigned char compression_method[2];
40 unsigned char mtime[2];
41 unsigned char mdate[2];
42 unsigned char crc32[4];
43 unsigned char compressed_size[4];
44 unsigned char size[4];
45 unsigned char filename_length[2];
46 unsigned char extra_length[2];
47 unsigned char comment_length[2];
48 unsigned char disk[2];
49 unsigned char attr1[2];
50 unsigned char attr2[4];
51 unsigned char offset[4];
52 unsigned char _end[1];
55 struct zip_dir_trailer {
56 unsigned char magic[4];
57 unsigned char disk[2];
58 unsigned char directory_start_disk[2];
59 unsigned char entries_on_this_disk[2];
60 unsigned char entries[2];
61 unsigned char size[4];
62 unsigned char offset[4];
63 unsigned char comment_length[2];
64 unsigned char _end[1];
68 * On ARM, padding is added at the end of the struct, so a simple
69 * sizeof(struct ...) reports two bytes more than the payload size
70 * we're interested in.
72 #define ZIP_LOCAL_HEADER_SIZE offsetof(struct zip_local_header, _end)
73 #define ZIP_DIR_HEADER_SIZE offsetof(struct zip_dir_header, _end)
74 #define ZIP_DIR_TRAILER_SIZE offsetof(struct zip_dir_trailer, _end)
76 static void copy_le16(unsigned char *dest, unsigned int n)
78 dest[0] = 0xff & n;
79 dest[1] = 0xff & (n >> 010);
82 static void copy_le32(unsigned char *dest, unsigned int n)
84 dest[0] = 0xff & n;
85 dest[1] = 0xff & (n >> 010);
86 dest[2] = 0xff & (n >> 020);
87 dest[3] = 0xff & (n >> 030);
90 static void *zlib_deflate(void *data, unsigned long size,
91 int compression_level, unsigned long *compressed_size)
93 z_stream stream;
94 unsigned long maxsize;
95 void *buffer;
96 int result;
98 memset(&stream, 0, sizeof(stream));
99 deflateInit(&stream, compression_level);
100 maxsize = deflateBound(&stream, size);
101 buffer = xmalloc(maxsize);
103 stream.next_in = data;
104 stream.avail_in = size;
105 stream.next_out = buffer;
106 stream.avail_out = maxsize;
108 do {
109 result = deflate(&stream, Z_FINISH);
110 } while (result == Z_OK);
112 if (result != Z_STREAM_END) {
113 free(buffer);
114 return NULL;
117 deflateEnd(&stream);
118 *compressed_size = stream.total_out;
120 return buffer;
123 static int write_zip_entry(struct archiver_args *args,
124 const unsigned char *sha1, const char *path, size_t pathlen,
125 unsigned int mode, void *buffer, unsigned long size)
127 struct zip_local_header header;
128 struct zip_dir_header dirent;
129 unsigned long attr2;
130 unsigned long compressed_size;
131 unsigned long uncompressed_size;
132 unsigned long crc;
133 unsigned long direntsize;
134 int method;
135 unsigned char *out;
136 void *deflated = NULL;
138 crc = crc32(0, NULL, 0);
140 if (pathlen > 0xffff) {
141 return error("path too long (%d chars, SHA1: %s): %s",
142 (int)pathlen, sha1_to_hex(sha1), path);
145 if (S_ISDIR(mode) || S_ISGITLINK(mode)) {
146 method = 0;
147 attr2 = 16;
148 out = NULL;
149 uncompressed_size = 0;
150 compressed_size = 0;
151 } else if (S_ISREG(mode) || S_ISLNK(mode)) {
152 method = 0;
153 attr2 = S_ISLNK(mode) ? ((mode | 0777) << 16) :
154 (mode & 0111) ? ((mode) << 16) : 0;
155 if (S_ISREG(mode) && args->compression_level != 0)
156 method = 8;
157 crc = crc32(crc, buffer, size);
158 out = buffer;
159 uncompressed_size = size;
160 compressed_size = size;
161 } else {
162 return error("unsupported file mode: 0%o (SHA1: %s)", mode,
163 sha1_to_hex(sha1));
166 if (method == 8) {
167 deflated = zlib_deflate(buffer, size, args->compression_level,
168 &compressed_size);
169 if (deflated && compressed_size - 6 < size) {
170 /* ZLIB --> raw compressed data (see RFC 1950) */
171 /* CMF and FLG ... */
172 out = (unsigned char *)deflated + 2;
173 compressed_size -= 6; /* ... and ADLER32 */
174 } else {
175 method = 0;
176 compressed_size = size;
180 /* make sure we have enough free space in the dictionary */
181 direntsize = ZIP_DIR_HEADER_SIZE + pathlen;
182 while (zip_dir_size < zip_dir_offset + direntsize) {
183 zip_dir_size += ZIP_DIRECTORY_MIN_SIZE;
184 zip_dir = xrealloc(zip_dir, zip_dir_size);
187 copy_le32(dirent.magic, 0x02014b50);
188 copy_le16(dirent.creator_version,
189 S_ISLNK(mode) || (S_ISREG(mode) && (mode & 0111)) ? 0x0317 : 0);
190 copy_le16(dirent.version, 10);
191 copy_le16(dirent.flags, 0);
192 copy_le16(dirent.compression_method, method);
193 copy_le16(dirent.mtime, zip_time);
194 copy_le16(dirent.mdate, zip_date);
195 copy_le32(dirent.crc32, crc);
196 copy_le32(dirent.compressed_size, compressed_size);
197 copy_le32(dirent.size, uncompressed_size);
198 copy_le16(dirent.filename_length, pathlen);
199 copy_le16(dirent.extra_length, 0);
200 copy_le16(dirent.comment_length, 0);
201 copy_le16(dirent.disk, 0);
202 copy_le16(dirent.attr1, 0);
203 copy_le32(dirent.attr2, attr2);
204 copy_le32(dirent.offset, zip_offset);
205 memcpy(zip_dir + zip_dir_offset, &dirent, ZIP_DIR_HEADER_SIZE);
206 zip_dir_offset += ZIP_DIR_HEADER_SIZE;
207 memcpy(zip_dir + zip_dir_offset, path, pathlen);
208 zip_dir_offset += pathlen;
209 zip_dir_entries++;
211 copy_le32(header.magic, 0x04034b50);
212 copy_le16(header.version, 10);
213 copy_le16(header.flags, 0);
214 copy_le16(header.compression_method, method);
215 copy_le16(header.mtime, zip_time);
216 copy_le16(header.mdate, zip_date);
217 copy_le32(header.crc32, crc);
218 copy_le32(header.compressed_size, compressed_size);
219 copy_le32(header.size, uncompressed_size);
220 copy_le16(header.filename_length, pathlen);
221 copy_le16(header.extra_length, 0);
222 write_or_die(1, &header, ZIP_LOCAL_HEADER_SIZE);
223 zip_offset += ZIP_LOCAL_HEADER_SIZE;
224 write_or_die(1, path, pathlen);
225 zip_offset += pathlen;
226 if (compressed_size > 0) {
227 write_or_die(1, out, compressed_size);
228 zip_offset += compressed_size;
231 free(deflated);
233 return 0;
236 static void write_zip_trailer(const unsigned char *sha1)
238 struct zip_dir_trailer trailer;
240 copy_le32(trailer.magic, 0x06054b50);
241 copy_le16(trailer.disk, 0);
242 copy_le16(trailer.directory_start_disk, 0);
243 copy_le16(trailer.entries_on_this_disk, zip_dir_entries);
244 copy_le16(trailer.entries, zip_dir_entries);
245 copy_le32(trailer.size, zip_dir_offset);
246 copy_le32(trailer.offset, zip_offset);
247 copy_le16(trailer.comment_length, sha1 ? 40 : 0);
249 write_or_die(1, zip_dir, zip_dir_offset);
250 write_or_die(1, &trailer, ZIP_DIR_TRAILER_SIZE);
251 if (sha1)
252 write_or_die(1, sha1_to_hex(sha1), 40);
255 static void dos_time(time_t *time, int *dos_date, int *dos_time)
257 struct tm *t = localtime(time);
259 *dos_date = t->tm_mday + (t->tm_mon + 1) * 32 +
260 (t->tm_year + 1900 - 1980) * 512;
261 *dos_time = t->tm_sec / 2 + t->tm_min * 32 + t->tm_hour * 2048;
264 int write_zip_archive(struct archiver_args *args)
266 int err;
268 dos_time(&args->time, &zip_date, &zip_time);
270 zip_dir = xmalloc(ZIP_DIRECTORY_MIN_SIZE);
271 zip_dir_size = ZIP_DIRECTORY_MIN_SIZE;
273 err = write_archive_entries(args, write_zip_entry);
274 if (!err)
275 write_zip_trailer(args->commit_sha1);
277 free(zip_dir);
279 return err;