]>
Commit | Line | Data |
---|---|---|
c38138cd LT |
1 | /* |
2 | * csum-file.c | |
3 | * | |
4 | * Copyright (C) 2005 Linus Torvalds | |
5 | * | |
6 | * Simple file write infrastructure for writing SHA1-summed | |
7 | * files. Useful when you write a file that you want to be | |
8 | * able to verify hasn't been messed with afterwards. | |
9 | */ | |
10 | #include "cache.h" | |
2a128d63 | 11 | #include "progress.h" |
c38138cd LT |
12 | #include "csum-file.h" |
13 | ||
98a3beab | 14 | static void flush(struct hashfile *f, const void *buf, unsigned int count) |
c38138cd | 15 | { |
e337a04d JH |
16 | if (0 <= f->check_fd && count) { |
17 | unsigned char check_buffer[8192]; | |
18 | ssize_t ret = read_in_full(f->check_fd, check_buffer, count); | |
19 | ||
20 | if (ret < 0) | |
21 | die_errno("%s: sha1 file read error", f->name); | |
61d36330 | 22 | if (ret != count) |
e337a04d JH |
23 | die("%s: sha1 file truncated", f->name); |
24 | if (memcmp(buf, check_buffer, count)) | |
25 | die("sha1 file '%s' validation error", f->name); | |
26 | } | |
27 | ||
68142e11 DS |
28 | if (write_in_full(f->fd, buf, count) < 0) { |
29 | if (errno == ENOSPC) | |
e1808845 | 30 | die("sha1 file '%s' write error. Out of diskspace", f->name); |
d824cbba | 31 | die_errno("sha1 file '%s' write error", f->name); |
c38138cd | 32 | } |
68142e11 DS |
33 | |
34 | f->total += count; | |
35 | display_throughput(f->tp, f->total); | |
c38138cd LT |
36 | } |
37 | ||
98a3beab | 38 | void hashflush(struct hashfile *f) |
c38138cd LT |
39 | { |
40 | unsigned offset = f->offset; | |
4c81b03e | 41 | |
c38138cd | 42 | if (offset) { |
4d273500 | 43 | the_hash_algo->update_fn(&f->ctx, f->buffer, offset); |
e782e12f | 44 | flush(f, f->buffer, offset); |
f0215369 | 45 | f->offset = 0; |
c38138cd | 46 | } |
838cd346 NP |
47 | } |
48 | ||
f2af9f5e | 49 | int finalize_hashfile(struct hashfile *f, unsigned char *result, unsigned int flags) |
838cd346 NP |
50 | { |
51 | int fd; | |
52 | ||
98a3beab | 53 | hashflush(f); |
4d273500 | 54 | the_hash_algo->final_fn(f->buffer, &f->ctx); |
ac0463ed NP |
55 | if (result) |
56 | hashcpy(result, f->buffer); | |
cfe83216 | 57 | if (flags & CSUM_HASH_IN_STREAM) |
4d273500 | 58 | flush(f, f->buffer, the_hash_algo->rawsz); |
cfe83216 DS |
59 | if (flags & CSUM_FSYNC) |
60 | fsync_or_die(f->fd, f->name); | |
61 | if (flags & CSUM_CLOSE) { | |
7ba502c4 | 62 | if (close(f->fd)) |
d824cbba | 63 | die_errno("%s: sha1 file error on close", f->name); |
7ba502c4 NP |
64 | fd = 0; |
65 | } else | |
66 | fd = f->fd; | |
e337a04d JH |
67 | if (0 <= f->check_fd) { |
68 | char discard; | |
69 | int cnt = read_in_full(f->check_fd, &discard, 1); | |
70 | if (cnt < 0) | |
71 | die_errno("%s: error when reading the tail of sha1 file", | |
72 | f->name); | |
73 | if (cnt) | |
74 | die("%s: sha1 file has trailing garbage", f->name); | |
75 | if (close(f->check_fd)) | |
76 | die_errno("%s: sha1 file error on close", f->name); | |
77 | } | |
7bf058f0 | 78 | free(f); |
7ba502c4 | 79 | return fd; |
c38138cd LT |
80 | } |
81 | ||
98a3beab | 82 | void hashwrite(struct hashfile *f, const void *buf, unsigned int count) |
c38138cd LT |
83 | { |
84 | while (count) { | |
ddaf1f62 | 85 | unsigned left = sizeof(f->buffer) - f->offset; |
c38138cd | 86 | unsigned nr = count > left ? left : count; |
a8032d12 NP |
87 | |
88 | if (f->do_crc) | |
89 | f->crc32 = crc32(f->crc32, buf, nr); | |
90 | ||
91 | if (nr == sizeof(f->buffer)) { | |
ddaf1f62 DS |
92 | /* |
93 | * Flush a full batch worth of data directly | |
94 | * from the input, skipping the memcpy() to | |
95 | * the hashfile's buffer. In this block, | |
96 | * f->offset is necessarily zero. | |
97 | */ | |
98 | the_hash_algo->update_fn(&f->ctx, buf, nr); | |
99 | flush(f, buf, nr); | |
a8032d12 | 100 | } else { |
ddaf1f62 DS |
101 | /* |
102 | * Copy to the hashfile's buffer, flushing only | |
103 | * if it became full. | |
104 | */ | |
105 | memcpy(f->buffer + f->offset, buf, nr); | |
106 | f->offset += nr; | |
107 | left -= nr; | |
108 | if (!left) | |
109 | hashflush(f); | |
a8032d12 | 110 | } |
c38138cd | 111 | |
c38138cd | 112 | count -= nr; |
1d7f171c | 113 | buf = (char *) buf + nr; |
c38138cd | 114 | } |
c38138cd LT |
115 | } |
116 | ||
98a3beab | 117 | struct hashfile *hashfd(int fd, const char *name) |
2a128d63 | 118 | { |
98a3beab | 119 | return hashfd_throughput(fd, name, NULL); |
2a128d63 NP |
120 | } |
121 | ||
98a3beab | 122 | struct hashfile *hashfd_check(const char *name) |
e337a04d JH |
123 | { |
124 | int sink, check; | |
98a3beab | 125 | struct hashfile *f; |
e337a04d JH |
126 | |
127 | sink = open("/dev/null", O_WRONLY); | |
128 | if (sink < 0) | |
599d2231 | 129 | die_errno("unable to open /dev/null"); |
e337a04d | 130 | check = open(name, O_RDONLY); |
599d2231 JK |
131 | if (check < 0) |
132 | die_errno("unable to open '%s'", name); | |
98a3beab | 133 | f = hashfd(sink, name); |
e337a04d JH |
134 | f->check_fd = check; |
135 | return f; | |
136 | } | |
137 | ||
98a3beab | 138 | struct hashfile *hashfd_throughput(int fd, const char *name, struct progress *tp) |
4397f014 | 139 | { |
98a3beab | 140 | struct hashfile *f = xmalloc(sizeof(*f)); |
4397f014 | 141 | f->fd = fd; |
e337a04d | 142 | f->check_fd = -1; |
4397f014 | 143 | f->offset = 0; |
218558af | 144 | f->total = 0; |
2a128d63 | 145 | f->tp = tp; |
ec640ed1 | 146 | f->name = name; |
78d1e84f | 147 | f->do_crc = 0; |
4d273500 | 148 | the_hash_algo->init_fn(&f->ctx); |
4397f014 LT |
149 | return f; |
150 | } | |
151 | ||
98a3beab | 152 | void hashfile_checkpoint(struct hashfile *f, struct hashfile_checkpoint *checkpoint) |
6c526148 | 153 | { |
98a3beab | 154 | hashflush(f); |
6c526148 | 155 | checkpoint->offset = f->total; |
768e30ea | 156 | the_hash_algo->clone_fn(&checkpoint->ctx, &f->ctx); |
6c526148 JH |
157 | } |
158 | ||
98a3beab | 159 | int hashfile_truncate(struct hashfile *f, struct hashfile_checkpoint *checkpoint) |
6c526148 JH |
160 | { |
161 | off_t offset = checkpoint->offset; | |
162 | ||
163 | if (ftruncate(f->fd, offset) || | |
164 | lseek(f->fd, offset, SEEK_SET) != offset) | |
165 | return -1; | |
166 | f->total = offset; | |
167 | f->ctx = checkpoint->ctx; | |
98a3beab | 168 | f->offset = 0; /* hashflush() was called in checkpoint */ |
6c526148 JH |
169 | return 0; |
170 | } | |
171 | ||
98a3beab | 172 | void crc32_begin(struct hashfile *f) |
78d1e84f | 173 | { |
1e4cd68c | 174 | f->crc32 = crc32(0, NULL, 0); |
78d1e84f NP |
175 | f->do_crc = 1; |
176 | } | |
c38138cd | 177 | |
98a3beab | 178 | uint32_t crc32_end(struct hashfile *f) |
78d1e84f NP |
179 | { |
180 | f->do_crc = 0; | |
181 | return f->crc32; | |
182 | } |