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synced 2024-08-27 19:49:21 +00:00
Refactored fast-import's internals for future additions.
Too many globals variables were being used not not enough code was resuable to process trees and commits so this is a simple refactoring of the existing blob processing code to get into a state that will be easier to handle trees and commits in. Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
This commit is contained in:
parent
27d6d29035
commit
ac47a738a7
149
fast-import.c
149
fast-import.c
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@ -18,22 +18,34 @@ struct object_entry_block
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struct object_entry_block *next_block;
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struct object_entry *next_free;
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struct object_entry *end;
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struct object_entry entries[0];
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struct object_entry entries[FLEX_ARRAY]; /* more */
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};
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struct last_object
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{
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void *data;
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unsigned long len;
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int depth;
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unsigned char sha1[20];
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};
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/* Stats and misc. counters. */
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static int max_depth = 10;
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static unsigned long alloc_count;
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static unsigned long object_count;
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static unsigned long duplicate_count;
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static unsigned long packoff;
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static int packfd;
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static int current_depth;
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static void *lastdat;
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static unsigned long lastdatlen;
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static unsigned char lastsha1[20];
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static unsigned char packsha1[20];
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struct object_entry *object_table[1 << 16];
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/* The .pack file */
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static int pack_fd;
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static unsigned long pack_offset;
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static unsigned char pack_sha1[20];
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/* Table of objects we've written. */
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struct object_entry_block *blocks;
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struct object_entry *object_table[1 << 16];
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/* Our last blob */
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struct last_object last_blob;
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static void alloc_objects(int cnt)
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{
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@ -115,7 +127,10 @@ static ssize_t ywrite(int fd, void *buffer, size_t length)
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return ret;
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}
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static unsigned long encode_header(enum object_type type, unsigned long size, unsigned char *hdr)
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static unsigned long encode_header(
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enum object_type type,
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unsigned long size,
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unsigned char *hdr)
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{
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int n = 1;
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unsigned char c;
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@ -135,41 +150,62 @@ static unsigned long encode_header(enum object_type type, unsigned long size, un
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return n;
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}
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static void write_blob(void *dat, unsigned long datlen)
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static int store_object(
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enum object_type type,
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void *dat,
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unsigned long datlen,
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struct last_object *last)
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{
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z_stream s;
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void *out, *delta;
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unsigned char hdr[64];
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struct object_entry *e;
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unsigned char hdr[96];
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unsigned char sha1[20];
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unsigned long hdrlen, deltalen;
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SHA_CTX c;
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z_stream s;
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if (lastdat && current_depth < max_depth) {
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delta = diff_delta(lastdat, lastdatlen,
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hdrlen = sprintf((char*)hdr,"%s %lu",type_names[type],datlen) + 1;
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SHA1_Init(&c);
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SHA1_Update(&c, hdr, hdrlen);
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SHA1_Update(&c, dat, datlen);
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SHA1_Final(sha1, &c);
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e = insert_object(sha1);
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if (e->offset) {
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duplicate_count++;
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return 0;
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}
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e->offset = pack_offset;
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object_count++;
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if (last->data && last->depth < max_depth)
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delta = diff_delta(last->data, last->len,
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dat, datlen,
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&deltalen, 0);
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} else
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else
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delta = 0;
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memset(&s, 0, sizeof(s));
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deflateInit(&s, zlib_compression_level);
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if (delta) {
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current_depth++;
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last->depth++;
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s.next_in = delta;
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s.avail_in = deltalen;
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hdrlen = encode_header(OBJ_DELTA, deltalen, hdr);
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if (ywrite(packfd, hdr, hdrlen) != hdrlen)
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if (ywrite(pack_fd, hdr, hdrlen) != hdrlen)
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die("Can't write object header: %s", strerror(errno));
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if (ywrite(packfd, lastsha1, sizeof(lastsha1)) != sizeof(lastsha1))
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if (ywrite(pack_fd, last->sha1, sizeof(sha1)) != sizeof(sha1))
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die("Can't write object base: %s", strerror(errno));
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packoff += hdrlen + sizeof(lastsha1);
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pack_offset += hdrlen + sizeof(sha1);
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} else {
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current_depth = 0;
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last->depth = 0;
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s.next_in = dat;
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s.avail_in = datlen;
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hdrlen = encode_header(OBJ_BLOB, datlen, hdr);
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if (ywrite(packfd, hdr, hdrlen) != hdrlen)
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hdrlen = encode_header(type, datlen, hdr);
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if (ywrite(pack_fd, hdr, hdrlen) != hdrlen)
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die("Can't write object header: %s", strerror(errno));
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packoff += hdrlen;
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pack_offset += hdrlen;
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}
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s.avail_out = deflateBound(&s, s.avail_in);
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@ -178,13 +214,19 @@ static void write_blob(void *dat, unsigned long datlen)
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/* nothing */;
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deflateEnd(&s);
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if (ywrite(packfd, out, s.total_out) != s.total_out)
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if (ywrite(pack_fd, out, s.total_out) != s.total_out)
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die("Failed writing compressed data %s", strerror(errno));
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packoff += s.total_out;
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pack_offset += s.total_out;
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free(out);
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if (delta)
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free(delta);
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if (last->data)
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free(last->data);
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last->data = dat;
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last->len = datlen;
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memcpy(last->sha1, sha1, sizeof(sha1));
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return 1;
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}
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static void init_pack_header()
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@ -195,13 +237,13 @@ static void init_pack_header()
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version = htonl(version);
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if (ywrite(packfd, (char*)magic, 4) != 4)
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if (ywrite(pack_fd, (char*)magic, 4) != 4)
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die("Can't write pack magic: %s", strerror(errno));
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if (ywrite(packfd, &version, 4) != 4)
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if (ywrite(pack_fd, &version, 4) != 4)
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die("Can't write pack version: %s", strerror(errno));
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if (ywrite(packfd, &zero, 4) != 4)
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if (ywrite(pack_fd, &zero, 4) != 4)
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die("Can't write 0 object count: %s", strerror(errno));
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packoff = 4 * 3;
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pack_offset = 4 * 3;
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}
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static void fixup_header_footer()
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@ -212,30 +254,30 @@ static void fixup_header_footer()
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char *buf;
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size_t n;
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if (lseek(packfd, 0, SEEK_SET) != 0)
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if (lseek(pack_fd, 0, SEEK_SET) != 0)
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die("Failed seeking to start: %s", strerror(errno));
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SHA1_Init(&c);
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if (yread(packfd, hdr, 8) != 8)
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if (yread(pack_fd, hdr, 8) != 8)
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die("Failed reading header: %s", strerror(errno));
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SHA1_Update(&c, hdr, 8);
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cnt = htonl(object_count);
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SHA1_Update(&c, &cnt, 4);
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if (ywrite(packfd, &cnt, 4) != 4)
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if (ywrite(pack_fd, &cnt, 4) != 4)
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die("Failed writing object count: %s", strerror(errno));
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buf = xmalloc(128 * 1024);
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for (;;) {
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n = xread(packfd, buf, 128 * 1024);
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n = xread(pack_fd, buf, 128 * 1024);
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if (n <= 0)
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break;
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SHA1_Update(&c, buf, n);
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}
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free(buf);
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SHA1_Final(packsha1, &c);
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if (ywrite(packfd, packsha1, sizeof(packsha1)) != sizeof(packsha1))
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SHA1_Final(pack_sha1, &c);
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if (ywrite(pack_fd, pack_sha1, sizeof(pack_sha1)) != sizeof(pack_sha1))
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die("Failed writing pack checksum: %s", strerror(errno));
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}
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@ -284,7 +326,7 @@ static void write_index(const char *idx_name)
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sha1write(f, &offset, 4);
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sha1write(f, (*c)->sha1, sizeof((*c)->sha1));
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}
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sha1write(f, packsha1, sizeof(packsha1));
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sha1write(f, pack_sha1, sizeof(pack_sha1));
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sha1close(f, NULL, 1);
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free(idx);
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}
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@ -301,53 +343,28 @@ int main(int argc, const char **argv)
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idx_name = xmalloc(strlen(base_name) + 5);
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sprintf(idx_name, "%s.idx", base_name);
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packfd = open(pack_name, O_RDWR|O_CREAT|O_EXCL, 0666);
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if (packfd < 0)
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pack_fd = open(pack_name, O_RDWR|O_CREAT|O_EXCL, 0666);
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if (pack_fd < 0)
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die("Can't create pack file %s: %s", pack_name, strerror(errno));
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alloc_objects(est_obj_cnt);
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init_pack_header();
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for (;;) {
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unsigned long datlen;
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int hdrlen;
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void *dat;
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char hdr[128];
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unsigned char sha1[20];
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SHA_CTX c;
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struct object_entry *e;
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if (yread(0, &datlen, 4) != 4)
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break;
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dat = xmalloc(datlen);
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if (yread(0, dat, datlen) != datlen)
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break;
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hdrlen = sprintf(hdr, "blob %lu", datlen) + 1;
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SHA1_Init(&c);
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SHA1_Update(&c, hdr, hdrlen);
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SHA1_Update(&c, dat, datlen);
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SHA1_Final(sha1, &c);
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e = insert_object(sha1);
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if (!e->offset) {
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e->offset = packoff;
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write_blob(dat, datlen);
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object_count++;
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if (lastdat)
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free(lastdat);
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lastdat = dat;
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lastdatlen = datlen;
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memcpy(lastsha1, sha1, sizeof(sha1));
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} else {
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duplicate_count++;
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if (!store_object(OBJ_BLOB, dat, datlen, &last_blob))
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free(dat);
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}
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}
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fixup_header_footer();
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close(packfd);
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close(pack_fd);
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write_index(idx_name);
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fprintf(stderr, "%lu objects, %lu duplicates, %lu allocated (%lu overflow)\n",
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