git-commit-vandalism/csum-file.c
Junio C Hamano f312de018b [PATCH] Let umask do its work upon filesystem object creation.
IIRC our strategy was to let the users' umask take care of the
final mode bits.  This patch fixes places that deviate from it.

Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-06 10:39:59 -07:00

148 lines
2.9 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 '%s' write error. Out of diskspace", f->name);
if (errno == EAGAIN || errno == EINTR)
continue;
die("sha1 file '%s' write error (%s)", f->name, strerror(errno));
}
}
int sha1close(struct sha1file *f, unsigned char *result, int update)
{
unsigned offset = f->offset;
if (offset) {
SHA1_Update(&f->ctx, f->buffer, offset);
sha1flush(f, offset);
}
SHA1_Final(f->buffer, &f->ctx);
if (result)
memcpy(result, f->buffer, 20);
if (update)
sha1flush(f, 20);
if (close(f->fd))
die("%s: sha1 file error on close (%s)", f->name, strerror(errno));
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;
buf += 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, ...)
{
struct sha1file *f;
unsigned len;
va_list arg;
int fd;
f = xmalloc(sizeof(*f));
va_start(arg, fmt);
len = vsnprintf(f->name, sizeof(f->name), fmt, arg);
va_end(arg);
if (len >= PATH_MAX)
die("you wascally wabbit, you");
f->namelen = len;
fd = open(f->name, O_CREAT | O_EXCL | O_WRONLY, 0666);
if (fd < 0)
die("unable to open %s (%s)", f->name, strerror(errno));
f->fd = fd;
f->error = 0;
f->offset = 0;
SHA1_Init(&f->ctx);
return f;
}
struct sha1file *sha1fd(int fd, const char *name)
{
struct sha1file *f;
unsigned len;
f = xmalloc(sizeof(*f));
len = strlen(name);
if (len >= PATH_MAX)
die("you wascally wabbit, you");
f->namelen = len;
memcpy(f->name, name, len+1);
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;
}