mirror of
https://github.com/git/git.git
synced 2024-09-28 03:00:25 +02:00
c38138cd78
We want to be able to check their integrity later, and putting the sha1-sum of the contents at the end is a good thing. The writing routines are generic, so we could try to re-use them for the index file, instead of having the same logic duplicated. Update unpack-objects to know about the extra 20 bytes at the end of the index.
121 lines
2.4 KiB
C
121 lines
2.4 KiB
C
/*
|
|
* csum-file.c
|
|
*
|
|
* Copyright (C) 2005 Linus Torvalds
|
|
*
|
|
* Simple file write infrastructure for writing SHA1-summed
|
|
* files. Useful when you write a file that you want to be
|
|
* able to verify hasn't been messed with afterwards.
|
|
*/
|
|
#include "cache.h"
|
|
#include "csum-file.h"
|
|
|
|
static int sha1flush(struct sha1file *f, unsigned int count)
|
|
{
|
|
void *buf = f->buffer;
|
|
|
|
for (;;) {
|
|
int ret = write(f->fd, buf, count);
|
|
if (ret > 0) {
|
|
buf += ret;
|
|
count -= ret;
|
|
if (count)
|
|
continue;
|
|
return 0;
|
|
}
|
|
if (!ret)
|
|
die("sha1 file write error. Out of diskspace");
|
|
if (errno == EAGAIN || errno == EINTR)
|
|
continue;
|
|
die("sha1 file write error (%s)", strerror(errno));
|
|
}
|
|
}
|
|
|
|
int sha1close(struct sha1file *f)
|
|
{
|
|
unsigned offset = f->offset;
|
|
if (offset) {
|
|
SHA1_Update(&f->ctx, f->buffer, offset);
|
|
sha1flush(f, offset);
|
|
}
|
|
SHA1_Final(f->buffer, &f->ctx);
|
|
sha1flush(f, 20);
|
|
return 0;
|
|
}
|
|
|
|
int sha1write(struct sha1file *f, void *buf, unsigned int count)
|
|
{
|
|
while (count) {
|
|
unsigned offset = f->offset;
|
|
unsigned left = sizeof(f->buffer) - offset;
|
|
unsigned nr = count > left ? left : count;
|
|
|
|
memcpy(f->buffer + offset, buf, nr);
|
|
count -= nr;
|
|
offset += nr;
|
|
left -= nr;
|
|
if (!left) {
|
|
SHA1_Update(&f->ctx, f->buffer, offset);
|
|
sha1flush(f, offset);
|
|
offset = 0;
|
|
}
|
|
f->offset = offset;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
struct sha1file *sha1create(const char *fmt, ...)
|
|
{
|
|
static char filename[PATH_MAX];
|
|
struct sha1file *f;
|
|
unsigned len;
|
|
va_list arg;
|
|
int fd;
|
|
|
|
va_start(arg, fmt);
|
|
len = vsnprintf(filename, PATH_MAX, fmt, arg);
|
|
va_end(arg);
|
|
|
|
if (len >= PATH_MAX)
|
|
die("you wascally wabbit, you");
|
|
fd = open(filename, O_CREAT | O_EXCL | O_WRONLY, 0644);
|
|
if (fd < 0)
|
|
die("unable to open %s (%s)", filename, strerror(errno));
|
|
f = xmalloc(sizeof(*f));
|
|
f->fd = fd;
|
|
f->error = 0;
|
|
f->offset = 0;
|
|
SHA1_Init(&f->ctx);
|
|
return f;
|
|
}
|
|
|
|
int sha1write_compressed(struct sha1file *f, void *in, unsigned int size)
|
|
{
|
|
z_stream stream;
|
|
unsigned long maxsize;
|
|
void *out;
|
|
|
|
memset(&stream, 0, sizeof(stream));
|
|
deflateInit(&stream, Z_DEFAULT_COMPRESSION);
|
|
maxsize = deflateBound(&stream, size);
|
|
out = xmalloc(maxsize);
|
|
|
|
/* Compress it */
|
|
stream.next_in = in;
|
|
stream.avail_in = size;
|
|
|
|
stream.next_out = out;
|
|
stream.avail_out = maxsize;
|
|
|
|
while (deflate(&stream, Z_FINISH) == Z_OK)
|
|
/* nothing */;
|
|
deflateEnd(&stream);
|
|
|
|
size = stream.total_out;
|
|
sha1write(f, out, size);
|
|
free(out);
|
|
return size;
|
|
}
|
|
|
|
|