Fix a comparison bug in diff-delta.c
[git/git.git] / csum-file.c
CommitLineData
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"
11#include "csum-file.h"
12
78b713a1 13static void sha1flush(struct sha1file *f, unsigned int count)
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14{
15 void *buf = f->buffer;
16
17 for (;;) {
1c15afb9 18 int ret = xwrite(f->fd, buf, count);
c38138cd 19 if (ret > 0) {
1d7f171c 20 buf = (char *) buf + ret;
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21 count -= ret;
22 if (count)
23 continue;
78b713a1 24 return;
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25 }
26 if (!ret)
e1808845 27 die("sha1 file '%s' write error. Out of diskspace", f->name);
e1808845 28 die("sha1 file '%s' write error (%s)", f->name, strerror(errno));
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29 }
30}
31
e1808845 32int sha1close(struct sha1file *f, unsigned char *result, int update)
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33{
34 unsigned offset = f->offset;
35 if (offset) {
36 SHA1_Update(&f->ctx, f->buffer, offset);
37 sha1flush(f, offset);
38 }
39 SHA1_Final(f->buffer, &f->ctx);
e1808845
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40 if (result)
41 memcpy(result, f->buffer, 20);
42 if (update)
43 sha1flush(f, 20);
44 if (close(f->fd))
45 die("%s: sha1 file error on close (%s)", f->name, strerror(errno));
7bf058f0 46 free(f);
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47 return 0;
48}
49
50int sha1write(struct sha1file *f, void *buf, unsigned int count)
51{
52 while (count) {
53 unsigned offset = f->offset;
54 unsigned left = sizeof(f->buffer) - offset;
55 unsigned nr = count > left ? left : count;
56
57 memcpy(f->buffer + offset, buf, nr);
58 count -= nr;
59 offset += nr;
1d7f171c 60 buf = (char *) buf + nr;
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61 left -= nr;
62 if (!left) {
63 SHA1_Update(&f->ctx, f->buffer, offset);
64 sha1flush(f, offset);
65 offset = 0;
66 }
67 f->offset = offset;
68 }
69 return 0;
70}
71
72struct sha1file *sha1create(const char *fmt, ...)
73{
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74 struct sha1file *f;
75 unsigned len;
76 va_list arg;
77 int fd;
78
e1808845
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79 f = xmalloc(sizeof(*f));
80
c38138cd 81 va_start(arg, fmt);
e1808845 82 len = vsnprintf(f->name, sizeof(f->name), fmt, arg);
c38138cd 83 va_end(arg);
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84 if (len >= PATH_MAX)
85 die("you wascally wabbit, you");
e1808845
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86 f->namelen = len;
87
f312de01 88 fd = open(f->name, O_CREAT | O_EXCL | O_WRONLY, 0666);
c38138cd 89 if (fd < 0)
e1808845 90 die("unable to open %s (%s)", f->name, strerror(errno));
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91 f->fd = fd;
92 f->error = 0;
93 f->offset = 0;
94 SHA1_Init(&f->ctx);
95 return f;
96}
97
4397f014
LT
98struct sha1file *sha1fd(int fd, const char *name)
99{
100 struct sha1file *f;
101 unsigned len;
102
103 f = xmalloc(sizeof(*f));
104
105 len = strlen(name);
106 if (len >= PATH_MAX)
107 die("you wascally wabbit, you");
108 f->namelen = len;
109 memcpy(f->name, name, len+1);
110
111 f->fd = fd;
112 f->error = 0;
113 f->offset = 0;
114 SHA1_Init(&f->ctx);
115 return f;
116}
117
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118int sha1write_compressed(struct sha1file *f, void *in, unsigned int size)
119{
120 z_stream stream;
121 unsigned long maxsize;
122 void *out;
123
124 memset(&stream, 0, sizeof(stream));
12f6c308 125 deflateInit(&stream, zlib_compression_level);
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126 maxsize = deflateBound(&stream, size);
127 out = xmalloc(maxsize);
128
129 /* Compress it */
130 stream.next_in = in;
131 stream.avail_in = size;
132
133 stream.next_out = out;
134 stream.avail_out = maxsize;
135
136 while (deflate(&stream, Z_FINISH) == Z_OK)
137 /* nothing */;
138 deflateEnd(&stream);
139
140 size = stream.total_out;
141 sha1write(f, out, size);
142 free(out);
143 return size;
144}
145
146