Skip to main content

Browse the archive

Staging
v0.8.1
Revision 68d06c5200775ffda91881254ca7a92f27db68ef authored by Jeff King on 19 February 2008, 16:25:22 UTC, committed by Junio C Hamano on 20 February 2008, 04:46:10 UTC 
Documentation/push: clarify matching refspec behavior
 
The previous text was correct, but it was easy to miss the
fact that we are talking about "matching" refs. That is, the
text can be parsed as "we push the union of the sets
of remote and local heads" and not "we push the intersection
of the sets of remote and local heads". (The former actually
doesn't make sense if you think about it, since we don't
even _have_ some of those heads). A careful reading would
reveal the correct meaning, but it makes sense to be as
explicit as possible in documentation.

We also explicitly use and introduce the term "matching";
this is a term discussed on the list, and it seems useful
to for users to be able to refer to this behavior by name.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
1 parent 2b8130c
Raw File
merge-file.c 
#include "cache.h"
#include "run-command.h"
#include "xdiff-interface.h"
#include "blob.h"

static int fill_mmfile_blob(mmfile_t *f, struct blob *obj)
{
	void *buf;
	unsigned long size;
	enum object_type type;

	buf = read_sha1_file(obj->object.sha1, &type, &size);
	if (!buf)
		return -1;
	if (type != OBJ_BLOB)
		return -1;
	f->ptr = buf;
	f->size = size;
	return 0;
}

static void free_mmfile(mmfile_t *f)
{
	free(f->ptr);
}

static void *three_way_filemerge(mmfile_t *base, mmfile_t *our, mmfile_t *their, unsigned long *size)
{
	mmbuffer_t res;
	xpparam_t xpp;
	int merge_status;

	memset(&xpp, 0, sizeof(xpp));
	merge_status = xdl_merge(base, our, ".our", their, ".their",
		&xpp, XDL_MERGE_ZEALOUS, &res);

	if (merge_status < 0)
		return NULL;

	*size = res.size;
	return res.ptr;
}

static int common_outf(void *priv_, mmbuffer_t *mb, int nbuf)
{
	int i;
	mmfile_t *dst = priv_;

	for (i = 0; i < nbuf; i++) {
		memcpy(dst->ptr + dst->size, mb[i].ptr, mb[i].size);
		dst->size += mb[i].size;
	}
	return 0;
}

static int generate_common_file(mmfile_t *res, mmfile_t *f1, mmfile_t *f2)
{
	unsigned long size = f1->size < f2->size ? f1->size : f2->size;
	void *ptr = xmalloc(size);
	xpparam_t xpp;
	xdemitconf_t xecfg;
	xdemitcb_t ecb;

	xpp.flags = XDF_NEED_MINIMAL;
	memset(&xecfg, 0, sizeof(xecfg));
	xecfg.ctxlen = 3;
	xecfg.flags = XDL_EMIT_COMMON;
	ecb.outf = common_outf;

	res->ptr = ptr;
	res->size = 0;

	ecb.priv = res;
	return xdi_diff(f1, f2, &xpp, &xecfg, &ecb);
}

void *merge_file(struct blob *base, struct blob *our, struct blob *their, unsigned long *size)
{
	void *res = NULL;
	mmfile_t f1, f2, common;

	/*
	 * Removed in either branch?
	 *
	 * NOTE! This depends on the caller having done the
	 * proper warning about removing a file that got
	 * modified in the other branch!
	 */
	if (!our || !their) {
		enum object_type type;
		if (base)
			return NULL;
		if (!our)
			our = their;
		return read_sha1_file(our->object.sha1, &type, size);
	}

	if (fill_mmfile_blob(&f1, our) < 0)
		goto out_no_mmfile;
	if (fill_mmfile_blob(&f2, their) < 0)
		goto out_free_f1;

	if (base) {
		if (fill_mmfile_blob(&common, base) < 0)
			goto out_free_f2_f1;
	} else {
		if (generate_common_file(&common, &f1, &f2) < 0)
			goto out_free_f2_f1;
	}
	res = three_way_filemerge(&common, &f1, &f2, size);
	free_mmfile(&common);
out_free_f2_f1:
	free_mmfile(&f2);
out_free_f1:
	free_mmfile(&f1);
out_no_mmfile:
	return res;
}
back to top