chore(3p/git): Unvendor git and track patches instead r/2903

This was vendored a long time ago under the expectation that keeping
it in sync with cgit would be easier this way, but it has proven not
to be a big issue.

On the other hand, a vendored copy of git is an annoying maintenance
burden. It is much easier to rebase the single (dottime) patch that we
have.

This removes the vendored copy of git and instead passes the git
source code to cgit via `pkgs.srcOnly`, which includes the applied
patch so that cgit can continue rendering dottime.

Change-Id: If31f62dea7ce688fd1b9050204e9378019775f2b

1 files changed, 0 insertions, 205 deletions

diff --git a/third_party/git/pack-revindex.c b/third_party/git/pack-revindex.c
deleted file mode 100644
index d28a7e43d0bd..000000000000
--- a/third_party/git/pack-revindex.c
+++ /dev/null
@@ -1,205 +0,0 @@
-#include "cache.h"
-#include "pack-revindex.h"
-#include "object-store.h"
-#include "packfile.h"
-
-/*
- * Pack index for existing packs give us easy access to the offsets into
- * corresponding pack file where each object's data starts, but the entries
- * do not store the size of the compressed representation (uncompressed
- * size is easily available by examining the pack entry header).  It is
- * also rather expensive to find the sha1 for an object given its offset.
- *
- * The pack index file is sorted by object name mapping to offset;
- * this revindex array is a list of offset/index_nr pairs
- * ordered by offset, so if you know the offset of an object, next offset
- * is where its packed representation ends and the index_nr can be used to
- * get the object sha1 from the main index.
- */
-
-/*
- * This is a least-significant-digit radix sort.
- *
- * It sorts each of the "n" items in "entries" by its offset field. The "max"
- * parameter must be at least as large as the largest offset in the array,
- * and lets us quit the sort early.
- */
-static void sort_revindex(struct revindex_entry *entries, unsigned n, off_t max)
-{
-	/*
-	 * We use a "digit" size of 16 bits. That keeps our memory
-	 * usage reasonable, and we can generally (for a 4G or smaller
-	 * packfile) quit after two rounds of radix-sorting.
-	 */
-#define DIGIT_SIZE (16)
-#define BUCKETS (1 << DIGIT_SIZE)
-	/*
-	 * We want to know the bucket that a[i] will go into when we are using
-	 * the digit that is N bits from the (least significant) end.
-	 */
-#define BUCKET_FOR(a, i, bits) (((a)[(i)].offset >> (bits)) & (BUCKETS-1))
-
-	/*
-	 * We need O(n) temporary storage. Rather than do an extra copy of the
-	 * partial results into "entries", we sort back and forth between the
-	 * real array and temporary storage. In each iteration of the loop, we
-	 * keep track of them with alias pointers, always sorting from "from"
-	 * to "to".
-	 */
-	struct revindex_entry *tmp, *from, *to;
-	int bits;
-	unsigned *pos;
-
-	ALLOC_ARRAY(pos, BUCKETS);
-	ALLOC_ARRAY(tmp, n);
-	from = entries;
-	to = tmp;
-
-	/*
-	 * If (max >> bits) is zero, then we know that the radix digit we are
-	 * on (and any higher) will be zero for all entries, and our loop will
-	 * be a no-op, as everybody lands in the same zero-th bucket.
-	 */
-	for (bits = 0; max >> bits; bits += DIGIT_SIZE) {
-		unsigned i;
-
-		memset(pos, 0, BUCKETS * sizeof(*pos));
-
-		/*
-		 * We want pos[i] to store the index of the last element that
-		 * will go in bucket "i" (actually one past the last element).
-		 * To do this, we first count the items that will go in each
-		 * bucket, which gives us a relative offset from the last
-		 * bucket. We can then cumulatively add the index from the
-		 * previous bucket to get the true index.
-		 */
-		for (i = 0; i < n; i++)
-			pos[BUCKET_FOR(from, i, bits)]++;
-		for (i = 1; i < BUCKETS; i++)
-			pos[i] += pos[i-1];
-
-		/*
-		 * Now we can drop the elements into their correct buckets (in
-		 * our temporary array).  We iterate the pos counter backwards
-		 * to avoid using an extra index to count up. And since we are
-		 * going backwards there, we must also go backwards through the
-		 * array itself, to keep the sort stable.
-		 *
-		 * Note that we use an unsigned iterator to make sure we can
-		 * handle 2^32-1 objects, even on a 32-bit system. But this
-		 * means we cannot use the more obvious "i >= 0" loop condition
-		 * for counting backwards, and must instead check for
-		 * wrap-around with UINT_MAX.
-		 */
-		for (i = n - 1; i != UINT_MAX; i--)
-			to[--pos[BUCKET_FOR(from, i, bits)]] = from[i];
-
-		/*
-		 * Now "to" contains the most sorted list, so we swap "from" and
-		 * "to" for the next iteration.
-		 */
-		SWAP(from, to);
-	}
-
-	/*
-	 * If we ended with our data in the original array, great. If not,
-	 * we have to move it back from the temporary storage.
-	 */
-	if (from != entries)
-		COPY_ARRAY(entries, tmp, n);
-	free(tmp);
-	free(pos);
-
-#undef BUCKET_FOR
-#undef BUCKETS
-#undef DIGIT_SIZE
-}
-
-/*
- * Ordered list of offsets of objects in the pack.
- */
-static void create_pack_revindex(struct packed_git *p)
-{
-	const unsigned num_ent = p->num_objects;
-	unsigned i;
-	const char *index = p->index_data;
-	const unsigned hashsz = the_hash_algo->rawsz;
-
-	ALLOC_ARRAY(p->revindex, num_ent + 1);
-	index += 4 * 256;
-
-	if (p->index_version > 1) {
-		const uint32_t *off_32 =
-			(uint32_t *)(index + 8 + p->num_objects * (hashsz + 4));
-		const uint32_t *off_64 = off_32 + p->num_objects;
-		for (i = 0; i < num_ent; i++) {
-			const uint32_t off = ntohl(*off_32++);
-			if (!(off & 0x80000000)) {
-				p->revindex[i].offset = off;
-			} else {
-				p->revindex[i].offset = get_be64(off_64);
-				off_64 += 2;
-			}
-			p->revindex[i].nr = i;
-		}
-	} else {
-		for (i = 0; i < num_ent; i++) {
-			const uint32_t hl = *((uint32_t *)(index + (hashsz + 4) * i));
-			p->revindex[i].offset = ntohl(hl);
-			p->revindex[i].nr = i;
-		}
-	}
-
-	/*
-	 * This knows the pack format -- the hash trailer
-	 * follows immediately after the last object data.
-	 */
-	p->revindex[num_ent].offset = p->pack_size - hashsz;
-	p->revindex[num_ent].nr = -1;
-	sort_revindex(p->revindex, num_ent, p->pack_size);
-}
-
-int load_pack_revindex(struct packed_git *p)
-{
-	if (!p->revindex) {
-		if (open_pack_index(p))
-			return -1;
-		create_pack_revindex(p);
-	}
-	return 0;
-}
-
-int find_revindex_position(struct packed_git *p, off_t ofs)
-{
-	int lo = 0;
-	int hi = p->num_objects + 1;
-	const struct revindex_entry *revindex = p->revindex;
-
-	do {
-		const unsigned mi = lo + (hi - lo) / 2;
-		if (revindex[mi].offset == ofs) {
-			return mi;
-		} else if (ofs < revindex[mi].offset)
-			hi = mi;
-		else
-			lo = mi + 1;
-	} while (lo < hi);
-
-	error("bad offset for revindex");
-	return -1;
-}
-
-struct revindex_entry *find_pack_revindex(struct packed_git *p, off_t ofs)
-{
-	int pos;
-
-	if (load_pack_revindex(p))
-		return NULL;
-
-	pos = find_revindex_position(p, ofs);
-
-	if (pos < 0)
-		return NULL;
-
-	return p->revindex + pos;
-}