git/csum-file.c
Shawn Pearce e702496e43 Convert memcpy(a,b,20) to hashcpy(a,b).
This abstracts away the size of the hash values when copying them
from memory location to memory location, much as the introduction
of hashcmp abstracted away hash value comparsion.

A few call sites were using char* rather than unsigned char* so
I added the cast rather than open hashcpy to be void*.  This is a
reasonable tradeoff as most call sites already use unsigned char*
and the existing hashcmp is also declared to be unsigned char*.

[jc: Splitted the patch to "master" part, to be followed by a
 patch for merge-recursive.c which is not in "master" yet.

 Fixed the cast in the latter hunk to combine-diff.c which was
 wrong in the original.

 Also converted ones left-over in combine-diff.c, diff-lib.c and
 upload-pack.c ]

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-08-23 13:53:10 -07:00

147 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 void sha1flush(struct sha1file *f, unsigned int count)
{
void *buf = f->buffer;
for (;;) {
int ret = xwrite(f->fd, buf, count);
if (ret > 0) {
buf = (char *) buf + ret;
count -= ret;
if (count)
continue;
return;
}
if (!ret)
die("sha1 file '%s' write error. Out of diskspace", f->name);
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)
hashcpy(result, f->buffer);
if (update)
sha1flush(f, 20);
if (close(f->fd))
die("%s: sha1 file error on close (%s)", f->name, strerror(errno));
free(f);
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 = (char *) 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, zlib_compression_level);
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;
}