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git-repack --max-pack-size: write_{object,one}() respect pack limit

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With --max-pack-size,  generate the appropriate write limit
for each object and check against it before each group of writes.
Update delta usability rules to handle base being in a previously-
written pack.  Inline sha1write_compress() so we know the
exact size of the written data when it needs to be compressed.
Detect and return write "failure".

Signed-off-by: Dana L. How <danahow@gmail.com>
Signed-off-by: Junio C Hamano <junkio@cox.net>
This commit is contained in:
Dana L. How 2007-05-13 12:06:18 -07:00 committed by Junio C Hamano
parent d01fb92f8d
commit 17b08f2cd0
1 changed files with 104 additions and 27 deletions
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131
builtin-pack-objects.c
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@ -352,16 +352,31 @@ static void copy_pack_data(struct sha1file *f,
}
static unsigned long write_object(struct sha1file *f,
struct object_entry *entry)
struct object_entry *entry,
off_t write_offset)
{
unsigned long size;
enum object_type type;
void *buf;
unsigned char header[10];
unsigned char dheader[10];
unsigned hdrlen;
off_t datalen;
enum object_type obj_type;
int to_reuse = 0;
/* write limit if limited packsize and not first object */
unsigned long limit = pack_size_limit && nr_written ?
pack_size_limit - write_offset : 0;
/* no if no delta */
int usable_delta = !entry->delta ? 0 :
/* yes if unlimited packfile */
!pack_size_limit ? 1 :
/* no if base written to previous pack */
entry->delta->offset == (off_t)-1 ? 0 :
/* otherwise double-check written to this
* pack, like we do below
*/
entry->delta->offset ? 1 : 0;
if (!pack_to_stdout)
crc32_begin(f);
@ -372,7 +387,9 @@ static unsigned long write_object(struct sha1file *f,
else if (!entry->in_pack)
to_reuse = 0; /* can't reuse what we don't have */
else if (obj_type == OBJ_REF_DELTA || obj_type == OBJ_OFS_DELTA)
to_reuse = 1; /* check_object() decided it for us */
/* check_object() decided it for us ... */
to_reuse = usable_delta;
/* ... but pack split may override that */
else if (obj_type != entry->in_pack_type)
to_reuse = 0; /* pack has delta which is unusable */
else if (entry->delta)
@ -383,24 +400,48 @@ static unsigned long write_object(struct sha1file *f,
*/
if (!to_reuse) {
z_stream stream;
unsigned long maxsize;
void *out;
buf = read_sha1_file(entry->sha1, &type, &size);
if (!buf)
die("unable to read %s", sha1_to_hex(entry->sha1));
if (size != entry->size)
die("object %s size inconsistency (%lu vs %lu)",
sha1_to_hex(entry->sha1), size, entry->size);
if (entry->delta) {
if (usable_delta) {
buf = delta_against(buf, size, entry);
size = entry->delta_size;
obj_type = (allow_ofs_delta && entry->delta->offset) ?
OBJ_OFS_DELTA : OBJ_REF_DELTA;
} else {
/*
* recover real object type in case
* check_object() wanted to re-use a delta,
* but we couldn't since base was in previous split pack
*/
obj_type = type;
}
/* compress the data to store and put compressed length in datalen */
memset(&stream, 0, sizeof(stream));
deflateInit(&stream, pack_compression_level);
maxsize = deflateBound(&stream, size);
out = xmalloc(maxsize);
/* Compress it */
stream.next_in = buf;
stream.avail_in = size;
stream.next_out = out;
stream.avail_out = maxsize;
while (deflate(&stream, Z_FINISH) == Z_OK)
/* nothing */;
deflateEnd(&stream);
datalen = stream.total_out;
deflateEnd(&stream);
/*
* The object header is a byte of 'type' followed by zero or
* more bytes of length.
*/
hdrlen = encode_header(obj_type, size, header);
sha1write(f, header, hdrlen);
if (obj_type == OBJ_OFS_DELTA) {
/*
@ -409,21 +450,41 @@ static unsigned long write_object(struct sha1file *f,
* base from this object's position in the pack.
*/
off_t ofs = entry->offset - entry->delta->offset;
unsigned pos = sizeof(header) - 1;
header[pos] = ofs & 127;
unsigned pos = sizeof(dheader) - 1;
dheader[pos] = ofs & 127;
while (ofs >>= 7)
header[--pos] = 128 | (--ofs & 127);
sha1write(f, header + pos, sizeof(header) - pos);
hdrlen += sizeof(header) - pos;
dheader[--pos] = 128 | (--ofs & 127);
if (limit && hdrlen + sizeof(dheader) - pos + datalen + 20 >= limit) {
free(out);
free(buf);
return 0;
}
sha1write(f, header, hdrlen);
sha1write(f, dheader + pos, sizeof(dheader) - pos);
hdrlen += sizeof(dheader) - pos;
} else if (obj_type == OBJ_REF_DELTA) {
/*
* Deltas with a base reference contain
* an additional 20 bytes for the base sha1.
*/
if (limit && hdrlen + 20 + datalen + 20 >= limit) {
free(out);
free(buf);
return 0;
}
sha1write(f, header, hdrlen);
sha1write(f, entry->delta->sha1, 20);
hdrlen += 20;
} else {
if (limit && hdrlen + datalen + 20 >= limit) {
free(out);
free(buf);
return 0;
}
sha1write(f, header, hdrlen);
}
datalen = sha1write_compressed(f, buf, size, pack_compression_level);
sha1write(f, out, datalen);
free(out);
free(buf);
}
else {
@ -438,20 +499,6 @@ static unsigned long write_object(struct sha1file *f,
reused_delta++;
}
hdrlen = encode_header(obj_type, entry->size, header);
sha1write(f, header, hdrlen);
if (obj_type == OBJ_OFS_DELTA) {
off_t ofs = entry->offset - entry->delta->offset;
unsigned pos = sizeof(header) - 1;
header[pos] = ofs & 127;
while (ofs >>= 7)
header[--pos] = 128 | (--ofs & 127);
sha1write(f, header + pos, sizeof(header) - pos);
hdrlen += sizeof(header) - pos;
} else if (obj_type == OBJ_REF_DELTA) {
sha1write(f, entry->delta->sha1, 20);
hdrlen += 20;
}
offset = entry->in_pack_offset;
revidx = find_packed_object(p, offset);
datalen = revidx[1].offset - offset;
@ -460,6 +507,29 @@ static unsigned long write_object(struct sha1file *f,
die("bad packed object CRC for %s", sha1_to_hex(entry->sha1));
offset += entry->in_pack_header_size;
datalen -= entry->in_pack_header_size;
if (obj_type == OBJ_OFS_DELTA) {
off_t ofs = entry->offset - entry->delta->offset;
unsigned pos = sizeof(dheader) - 1;
dheader[pos] = ofs & 127;
while (ofs >>= 7)
dheader[--pos] = 128 | (--ofs & 127);
if (limit && hdrlen + sizeof(dheader) - pos + datalen + 20 >= limit)
return 0;
sha1write(f, header, hdrlen);
sha1write(f, dheader + pos, sizeof(dheader) - pos);
hdrlen += sizeof(dheader) - pos;
} else if (obj_type == OBJ_REF_DELTA) {
if (limit && hdrlen + 20 + datalen + 20 >= limit)
return 0;
sha1write(f, header, hdrlen);
sha1write(f, entry->delta->sha1, 20);
hdrlen += 20;
} else {
if (limit && hdrlen + datalen + 20 >= limit)
return 0;
sha1write(f, header, hdrlen);
}
if (!pack_to_stdout && p->index_version == 1 &&
check_pack_inflate(p, &w_curs, offset, datalen, entry->size))
die("corrupt packed object for %s", sha1_to_hex(entry->sha1));
@ -467,7 +537,7 @@ static unsigned long write_object(struct sha1file *f,
unuse_pack(&w_curs);
reused++;
}
if (entry->delta)
if (usable_delta)
written_delta++;
written++;
if (!pack_to_stdout)
@ -486,11 +556,18 @@ static off_t write_one(struct sha1file *f,
return offset;
/* if we are deltified, write out base object first. */
if (e->delta)
if (e->delta) {
offset = write_one(f, e->delta, offset);
if (!offset)
return 0;
}
e->offset = offset;
size = write_object(f, e);
size = write_object(f, e, offset);
if (!size) {
e->offset = 0;
return 0;
}
/* make sure off_t is sufficiently large not to wrap */
if (offset > offset + size)