]>
Commit | Line | Data |
---|---|---|
e83c5163 LT |
1 | #include "cache.h" |
2 | ||
3 | const char *sha1_file_directory = NULL; | |
4 | struct cache_entry **active_cache = NULL; | |
5 | unsigned int active_nr = 0, active_alloc = 0; | |
6 | ||
7 | void usage(const char *err) | |
8 | { | |
9 | fprintf(stderr, "read-tree: %s\n", err); | |
10 | exit(1); | |
11 | } | |
12 | ||
13 | static unsigned hexval(char c) | |
14 | { | |
15 | if (c >= '0' && c <= '9') | |
16 | return c - '0'; | |
17 | if (c >= 'a' && c <= 'f') | |
18 | return c - 'a' + 10; | |
19 | if (c >= 'A' && c <= 'F') | |
20 | return c - 'A' + 10; | |
21 | return ~0; | |
22 | } | |
23 | ||
24 | int get_sha1_hex(char *hex, unsigned char *sha1) | |
25 | { | |
26 | int i; | |
27 | for (i = 0; i < 20; i++) { | |
28 | unsigned int val = (hexval(hex[0]) << 4) | hexval(hex[1]); | |
29 | if (val & ~0xff) | |
30 | return -1; | |
31 | *sha1++ = val; | |
32 | hex += 2; | |
33 | } | |
34 | return 0; | |
35 | } | |
36 | ||
37 | char * sha1_to_hex(unsigned char *sha1) | |
38 | { | |
39 | static char buffer[50]; | |
40 | static const char hex[] = "0123456789abcdef"; | |
41 | char *buf = buffer; | |
42 | int i; | |
43 | ||
44 | for (i = 0; i < 20; i++) { | |
45 | unsigned int val = *sha1++; | |
46 | *buf++ = hex[val >> 4]; | |
47 | *buf++ = hex[val & 0xf]; | |
48 | } | |
49 | return buffer; | |
50 | } | |
51 | ||
52 | /* | |
53 | * NOTE! This returns a statically allocated buffer, so you have to be | |
54 | * careful about using it. Do a "strdup()" if you need to save the | |
55 | * filename. | |
56 | */ | |
57 | char *sha1_file_name(unsigned char *sha1) | |
58 | { | |
59 | int i; | |
60 | static char *name, *base; | |
61 | ||
62 | if (!base) { | |
63 | char *sha1_file_directory = getenv(DB_ENVIRONMENT) ? : DEFAULT_DB_ENVIRONMENT; | |
64 | int len = strlen(sha1_file_directory); | |
65 | base = malloc(len + 60); | |
66 | memcpy(base, sha1_file_directory, len); | |
67 | memset(base+len, 0, 60); | |
68 | base[len] = '/'; | |
69 | base[len+3] = '/'; | |
70 | name = base + len + 1; | |
71 | } | |
72 | for (i = 0; i < 20; i++) { | |
73 | static char hex[] = "0123456789abcdef"; | |
74 | unsigned int val = sha1[i]; | |
75 | char *pos = name + i*2 + (i > 0); | |
76 | *pos++ = hex[val >> 4]; | |
77 | *pos = hex[val & 0xf]; | |
78 | } | |
79 | return base; | |
80 | } | |
81 | ||
82 | void * read_sha1_file(unsigned char *sha1, char *type, unsigned long *size) | |
83 | { | |
84 | z_stream stream; | |
85 | char buffer[8192]; | |
86 | struct stat st; | |
87 | int i, fd, ret, bytes; | |
88 | void *map, *buf; | |
89 | char *filename = sha1_file_name(sha1); | |
90 | ||
91 | fd = open(filename, O_RDONLY); | |
92 | if (fd < 0) { | |
93 | perror(filename); | |
94 | return NULL; | |
95 | } | |
96 | if (fstat(fd, &st) < 0) { | |
97 | close(fd); | |
98 | return NULL; | |
99 | } | |
100 | map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0); | |
101 | close(fd); | |
102 | if (-1 == (int)(long)map) | |
103 | return NULL; | |
104 | ||
105 | /* Get the data stream */ | |
106 | memset(&stream, 0, sizeof(stream)); | |
107 | stream.next_in = map; | |
108 | stream.avail_in = st.st_size; | |
109 | stream.next_out = buffer; | |
110 | stream.avail_out = sizeof(buffer); | |
111 | ||
112 | inflateInit(&stream); | |
113 | ret = inflate(&stream, 0); | |
114 | if (sscanf(buffer, "%10s %lu", type, size) != 2) | |
115 | return NULL; | |
116 | bytes = strlen(buffer) + 1; | |
117 | buf = malloc(*size); | |
118 | if (!buf) | |
119 | return NULL; | |
120 | ||
121 | memcpy(buf, buffer + bytes, stream.total_out - bytes); | |
122 | bytes = stream.total_out - bytes; | |
123 | if (bytes < *size && ret == Z_OK) { | |
124 | stream.next_out = buf + bytes; | |
125 | stream.avail_out = *size - bytes; | |
126 | while (inflate(&stream, Z_FINISH) == Z_OK) | |
127 | /* nothing */; | |
128 | } | |
129 | inflateEnd(&stream); | |
130 | return buf; | |
131 | } | |
132 | ||
133 | int write_sha1_file(char *buf, unsigned len) | |
134 | { | |
135 | int size; | |
136 | char *compressed; | |
137 | z_stream stream; | |
138 | unsigned char sha1[20]; | |
139 | SHA_CTX c; | |
140 | ||
141 | /* Set it up */ | |
142 | memset(&stream, 0, sizeof(stream)); | |
143 | deflateInit(&stream, Z_BEST_COMPRESSION); | |
144 | size = deflateBound(&stream, len); | |
145 | compressed = malloc(size); | |
146 | ||
147 | /* Compress it */ | |
148 | stream.next_in = buf; | |
149 | stream.avail_in = len; | |
150 | stream.next_out = compressed; | |
151 | stream.avail_out = size; | |
152 | while (deflate(&stream, Z_FINISH) == Z_OK) | |
153 | /* nothing */; | |
154 | deflateEnd(&stream); | |
155 | size = stream.total_out; | |
156 | ||
157 | /* Sha1.. */ | |
158 | SHA1_Init(&c); | |
159 | SHA1_Update(&c, compressed, size); | |
160 | SHA1_Final(sha1, &c); | |
161 | ||
162 | if (write_sha1_buffer(sha1, compressed, size) < 0) | |
163 | return -1; | |
164 | printf("%s\n", sha1_to_hex(sha1)); | |
165 | return 0; | |
166 | } | |
167 | ||
168 | int write_sha1_buffer(unsigned char *sha1, void *buf, unsigned int size) | |
169 | { | |
170 | char *filename = sha1_file_name(sha1); | |
171 | int i, fd; | |
172 | ||
173 | fd = open(filename, O_WRONLY | O_CREAT | O_EXCL, 0666); | |
174 | if (fd < 0) | |
175 | return (errno == EEXIST) ? 0 : -1; | |
176 | write(fd, buf, size); | |
177 | close(fd); | |
178 | return 0; | |
179 | } | |
180 | ||
181 | static int error(const char * string) | |
182 | { | |
183 | fprintf(stderr, "error: %s\n", string); | |
184 | return -1; | |
185 | } | |
186 | ||
187 | static int verify_hdr(struct cache_header *hdr, unsigned long size) | |
188 | { | |
189 | SHA_CTX c; | |
190 | unsigned char sha1[20]; | |
191 | ||
192 | if (hdr->signature != CACHE_SIGNATURE) | |
193 | return error("bad signature"); | |
194 | if (hdr->version != 1) | |
195 | return error("bad version"); | |
196 | SHA1_Init(&c); | |
197 | SHA1_Update(&c, hdr, offsetof(struct cache_header, sha1)); | |
198 | SHA1_Update(&c, hdr+1, size - sizeof(*hdr)); | |
199 | SHA1_Final(sha1, &c); | |
200 | if (memcmp(sha1, hdr->sha1, 20)) | |
201 | return error("bad header sha1"); | |
202 | return 0; | |
203 | } | |
204 | ||
205 | int read_cache(void) | |
206 | { | |
207 | int fd, i; | |
208 | struct stat st; | |
209 | unsigned long size, offset; | |
210 | void *map; | |
211 | struct cache_header *hdr; | |
212 | ||
213 | errno = EBUSY; | |
214 | if (active_cache) | |
215 | return error("more than one cachefile"); | |
216 | errno = ENOENT; | |
217 | sha1_file_directory = getenv(DB_ENVIRONMENT); | |
218 | if (!sha1_file_directory) | |
219 | sha1_file_directory = DEFAULT_DB_ENVIRONMENT; | |
220 | if (access(sha1_file_directory, X_OK) < 0) | |
221 | return error("no access to SHA1 file directory"); | |
222 | fd = open(".dircache/index", O_RDONLY); | |
223 | if (fd < 0) | |
224 | return (errno == ENOENT) ? 0 : error("open failed"); | |
225 | ||
226 | map = (void *)-1; | |
227 | if (!fstat(fd, &st)) { | |
228 | map = NULL; | |
229 | size = st.st_size; | |
230 | errno = EINVAL; | |
231 | if (size > sizeof(struct cache_header)) | |
232 | map = mmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0); | |
233 | } | |
234 | close(fd); | |
235 | if (-1 == (int)(long)map) | |
236 | return error("mmap failed"); | |
237 | ||
238 | hdr = map; | |
239 | if (verify_hdr(hdr, size) < 0) | |
240 | goto unmap; | |
241 | ||
242 | active_nr = hdr->entries; | |
243 | active_alloc = alloc_nr(active_nr); | |
244 | active_cache = calloc(active_alloc, sizeof(struct cache_entry *)); | |
245 | ||
246 | offset = sizeof(*hdr); | |
247 | for (i = 0; i < hdr->entries; i++) { | |
248 | struct cache_entry *ce = map + offset; | |
249 | offset = offset + ce_size(ce); | |
250 | active_cache[i] = ce; | |
251 | } | |
252 | return active_nr; | |
253 | ||
254 | unmap: | |
255 | munmap(map, size); | |
256 | errno = EINVAL; | |
257 | return error("verify header failed"); | |
258 | } | |
259 |