improve reliability of fixup_pack_header_footer()
[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"
2a128d63 11#include "progress.h"
c38138cd
LT
12#include "csum-file.h"
13
78b713a1 14static void sha1flush(struct sha1file *f, unsigned int count)
c38138cd
LT
15{
16 void *buf = f->buffer;
17
18 for (;;) {
1c15afb9 19 int ret = xwrite(f->fd, buf, count);
c38138cd 20 if (ret > 0) {
218558af
NP
21 f->total += ret;
22 display_throughput(f->tp, f->total);
1d7f171c 23 buf = (char *) buf + ret;
c38138cd
LT
24 count -= ret;
25 if (count)
26 continue;
78b713a1 27 return;
c38138cd
LT
28 }
29 if (!ret)
e1808845 30 die("sha1 file '%s' write error. Out of diskspace", f->name);
e1808845 31 die("sha1 file '%s' write error (%s)", f->name, strerror(errno));
c38138cd
LT
32 }
33}
34
4c81b03e 35int sha1close(struct sha1file *f, unsigned char *result, unsigned int flags)
c38138cd 36{
7ba502c4 37 int fd;
c38138cd 38 unsigned offset = f->offset;
4c81b03e 39
c38138cd
LT
40 if (offset) {
41 SHA1_Update(&f->ctx, f->buffer, offset);
42 sha1flush(f, offset);
f0215369 43 f->offset = 0;
c38138cd 44 }
4c81b03e 45 if (flags & (CSUM_CLOSE | CSUM_FSYNC)) {
7ba502c4
NP
46 /* write checksum and close fd */
47 SHA1_Final(f->buffer, &f->ctx);
48 if (result)
49 hashcpy(result, f->buffer);
50 sha1flush(f, 20);
4c81b03e
LT
51 if (flags & CSUM_FSYNC)
52 fsync_or_die(f->fd, f->name);
7ba502c4
NP
53 if (close(f->fd))
54 die("%s: sha1 file error on close (%s)",
55 f->name, strerror(errno));
56 fd = 0;
57 } else
58 fd = f->fd;
7bf058f0 59 free(f);
7ba502c4 60 return fd;
c38138cd
LT
61}
62
63int sha1write(struct sha1file *f, void *buf, unsigned int count)
64{
78d1e84f
NP
65 if (f->do_crc)
66 f->crc32 = crc32(f->crc32, buf, count);
c38138cd
LT
67 while (count) {
68 unsigned offset = f->offset;
69 unsigned left = sizeof(f->buffer) - offset;
70 unsigned nr = count > left ? left : count;
71
72 memcpy(f->buffer + offset, buf, nr);
73 count -= nr;
74 offset += nr;
1d7f171c 75 buf = (char *) buf + nr;
c38138cd
LT
76 left -= nr;
77 if (!left) {
78 SHA1_Update(&f->ctx, f->buffer, offset);
79 sha1flush(f, offset);
80 offset = 0;
81 }
82 f->offset = offset;
83 }
84 return 0;
85}
86
4397f014 87struct sha1file *sha1fd(int fd, const char *name)
2a128d63
NP
88{
89 return sha1fd_throughput(fd, name, NULL);
90}
91
92struct sha1file *sha1fd_throughput(int fd, const char *name, struct progress *tp)
4397f014 93{
ec640ed1 94 struct sha1file *f = xmalloc(sizeof(*f));
4397f014 95 f->fd = fd;
4397f014 96 f->offset = 0;
218558af 97 f->total = 0;
2a128d63 98 f->tp = tp;
ec640ed1 99 f->name = name;
78d1e84f 100 f->do_crc = 0;
4397f014
LT
101 SHA1_Init(&f->ctx);
102 return f;
103}
104
78d1e84f
NP
105void crc32_begin(struct sha1file *f)
106{
107 f->crc32 = crc32(0, Z_NULL, 0);
108 f->do_crc = 1;
109}
c38138cd 110
78d1e84f
NP
111uint32_t crc32_end(struct sha1file *f)
112{
113 f->do_crc = 0;
114 return f->crc32;
115}