mirrors/git
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

git-pack-objects: write the pack files with a SHA1 csum

Browse Source 
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.
This commit is contained in:
Linus Torvalds
2005-06-26 20:27:56 -07:00
parent 9b66ec0474
commit c38138cd78
5 changed files with 158 additions and 62 deletions
Download Patch File Download Diff File Expand all files Collapse all files

66
pack-objects.c
View File

@ -2,6 +2,7 @@
#include "cache.h"
#include "object.h"
#include "delta.h"
#include "csum-file.h"
static const char pack_usage[] = "git-pack-objects [--window=N] [--depth=N] base-name < object-list";
@ -29,51 +30,6 @@ static struct object_entry *objects = NULL;
static int nr_objects = 0, nr_alloc = 0;
static const char *base_name;
struct myfile {
int fd;
unsigned long chars;
unsigned char buffer[8192];
};
static FILE *create_file(const char *suffix)
{
static char filename[PATH_MAX];
unsigned len;
len = snprintf(filename, PATH_MAX, "%s.%s", base_name, suffix);
if (len >= PATH_MAX)
die("you wascally wabbit, you");
return fopen(filename, "w");
}
static unsigned long fwrite_compressed(void *in, unsigned long size, FILE *f)
{
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;
fwrite(out, size, 1, f);
free(out);
return size;
}
static void *delta_against(void *buf, unsigned long size, struct object_entry *entry)
{
unsigned long othersize, delta_size;
@ -92,7 +48,7 @@ static void *delta_against(void *buf, unsigned long size, struct object_entry *e
return delta_buf;
}
static unsigned long write_object(FILE *f, struct object_entry *entry)
static unsigned long write_object(struct sha1file *f, struct object_entry *entry)
{
unsigned long size;
char type[10];
@ -121,8 +77,8 @@ static unsigned long write_object(FILE *f, struct object_entry *entry)
}
datalen = htonl(size);
memcpy(header+1, &datalen, 4);
fwrite(header, hdrlen, 1, f);
datalen = fwrite_compressed(buf, size, f);
sha1write(f, header, hdrlen);
datalen = sha1write_compressed(f, buf, size);
free(buf);
return hdrlen + datalen;
}
@ -130,7 +86,7 @@ static unsigned long write_object(FILE *f, struct object_entry *entry)
static void write_pack_file(void)
{
int i;
FILE *f = create_file("pack");
struct sha1file *f = sha1create("%s.%s", base_name, "pack");
unsigned long offset = 0;
unsigned long mb;
@ -139,7 +95,7 @@ static void write_pack_file(void)
entry->offset = offset;
offset += write_object(f, entry);
}
fclose(f);
sha1close(f);
mb = offset >> 20;
offset &= 0xfffff;
}
@ -147,7 +103,7 @@ static void write_pack_file(void)
static void write_index_file(void)
{
int i;
FILE *f = create_file("idx");
struct sha1file *f = sha1create("%s.%s", base_name, "idx");
struct object_entry **list = sorted_by_sha;
struct object_entry **last = list + nr_objects;
unsigned int array[256];
@ -168,7 +124,7 @@ static void write_index_file(void)
array[i] = htonl(next - sorted_by_sha);
list = next;
}
fwrite(array, 256, sizeof(int), f);
sha1write(f, array, 256 * sizeof(int));
/*
* Write the actual SHA1 entries..
@ -177,10 +133,10 @@ static void write_index_file(void)
for (i = 0; i < nr_objects; i++) {
struct object_entry *entry = *list++;
unsigned int offset = htonl(entry->offset);
fwrite(&offset, 4, 1, f);
fwrite(entry->sha1, 20, 1, f);
sha1write(f, &offset, 4);
sha1write(f, entry->sha1, 20);
}
fclose(f);
sha1close(f);
}
static void add_object_entry(unsigned char *sha1, unsigned int hash)