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	#include "git-compat-util.h"
	#include "line-range.h"
	#include "cache.h"
	#include "tag.h"
	#include "blob.h"
	#include "tree.h"
	#include "diff.h"
	#include "commit.h"
	#include "decorate.h"
	#include "revision.h"
	#include "xdiff-interface.h"
	#include "strbuf.h"
	#include "log-tree.h"
	#include "graph.h"
	#include "userdiff.h"
	#include "line-log.h"
	#include "strvec.h"
	#include "bloom.h"

	static void range_set_grow(struct range_set *rs, size_t extra)
	{
	ALLOC_GROW(rs->ranges, rs->nr + extra, rs->alloc);
	}

	/* Either initialization would be fine */
	#define RANGE_SET_INIT {0}

	void range_set_init(struct range_set *rs, size_t prealloc)
	{
	rs->alloc = rs->nr = 0;
	rs->ranges = NULL;
	if (prealloc)
	range_set_grow(rs, prealloc);
	}

	void range_set_release(struct range_set *rs)
	{
	FREE_AND_NULL(rs->ranges);
	rs->alloc = rs->nr = 0;
	}

	/* dst must be uninitialized! */
	static void range_set_copy(struct range_set dst, struct range_set src)
	{
	range_set_init(dst, src->nr);
	COPY_ARRAY(dst->ranges, src->ranges, src->nr);
	dst->nr = src->nr;
	}

	static void range_set_move(struct range_set dst, struct range_set src)
	{
	range_set_release(dst);
	dst->ranges = src->ranges;
	dst->nr = src->nr;
	dst->alloc = src->alloc;
	src->ranges = NULL;
	src->alloc = src->nr = 0;
	}

	/* tack on a _new_ range _at the end_ */
	void range_set_append_unsafe(struct range_set *rs, long a, long b)
	{
	assert(a <= b);
	range_set_grow(rs, 1);
	rs->ranges[rs->nr].start = a;
	rs->ranges[rs->nr].end = b;
	rs->nr++;
	}

	void range_set_append(struct range_set *rs, long a, long b)
	{
	assert(rs->nr == 0 \|\| rs->ranges[rs->nr-1].end <= a);
	range_set_append_unsafe(rs, a, b);
	}

	static int range_cmp(const void _r, const void _s)
	{
	const struct range *r = _r;
	const struct range *s = _s;

	/* this could be simply 'return r.start-s.start', but for the types */
	if (r->start == s->start)
	return 0;
	if (r->start < s->start)
	return -1;
	return 1;
	}

	/*
	* Check that the ranges are non-empty, sorted and non-overlapping
	*/
	static void range_set_check_invariants(struct range_set *rs)
	{
	unsigned int i;

	if (!rs)
	return;

	if (rs->nr)
	assert(rs->ranges[0].start < rs->ranges[0].end);

	for (i = 1; i < rs->nr; i++) {
	assert(rs->ranges[i-1].end < rs->ranges[i].start);
	assert(rs->ranges[i].start < rs->ranges[i].end);
	}
	}

	/*
	* In-place pass of sorting and merging the ranges in the range set,
	* to establish the invariants when we get the ranges from the user
	*/
	void sort_and_merge_range_set(struct range_set *rs)
	{
	unsigned int i;
	unsigned int o = 0; /* output cursor */

	QSORT(rs->ranges, rs->nr, range_cmp);

	for (i = 0; i < rs->nr; i++) {
	if (rs->ranges[i].start == rs->ranges[i].end)
	continue;
	if (o > 0 && rs->ranges[i].start <= rs->ranges[o-1].end) {
	if (rs->ranges[o-1].end < rs->ranges[i].end)
	rs->ranges[o-1].end = rs->ranges[i].end;
	} else {
	rs->ranges[o].start = rs->ranges[i].start;
	rs->ranges[o].end = rs->ranges[i].end;
	o++;
	}
	}
	assert(o <= rs->nr);
	rs->nr = o;

	range_set_check_invariants(rs);
	}

	/*
	* Union of range sets (i.e., sets of line numbers). Used to merge
	* them when searches meet at a common ancestor.
	*
	* This is also where the ranges are consolidated into canonical form:
	* overlapping and adjacent ranges are merged, and empty ranges are
	* removed.
	*/
	static void range_set_union(struct range_set *out,
	struct range_set a, struct range_set b)
	{
	unsigned int i = 0, j = 0;
	struct range *ra = a->ranges;
	struct range *rb = b->ranges;
	/* cannot make an alias of out->ranges: it may change during grow */

	assert(out->nr == 0);
	while (i < a->nr \|\| j < b->nr) {
	struct range *new_range;
	if (i < a->nr && j < b->nr) {
	if (ra[i].start < rb[j].start)
	new_range = &ra[i++];
	else if (ra[i].start > rb[j].start)
	new_range = &rb[j++];
	else if (ra[i].end < rb[j].end)
	new_range = &ra[i++];
	else
	new_range = &rb[j++];
	} else if (i < a->nr) /* b exhausted */
	new_range = &ra[i++];
	else /* a exhausted */
	new_range = &rb[j++];
	if (new_range->start == new_range->end)
	; /* empty range */
	else if (!out->nr \|\| out->ranges[out->nr-1].end < new_range->start) {
	range_set_grow(out, 1);
	out->ranges[out->nr].start = new_range->start;
	out->ranges[out->nr].end = new_range->end;
	out->nr++;
	} else if (out->ranges[out->nr-1].end < new_range->end) {
	out->ranges[out->nr-1].end = new_range->end;
	}
	}
	}

	/*
	* Difference of range sets (out = a \ b). Pass the "interesting"
	* ranges as 'a' and the target side of the diff as 'b': it removes
	* the ranges for which the commit is responsible.
	*/
	static void range_set_difference(struct range_set *out,
	struct range_set a, struct range_set b)
	{
	unsigned int i, j = 0;
	for (i = 0; i < a->nr; i++) {
	long start = a->ranges[i].start;
	long end = a->ranges[i].end;
	while (start < end) {
	while (j < b->nr && start >= b->ranges[j].end)
	/*
	* a: \|-------
	* b: ------\|
	*/
	j++;
	if (j >= b->nr \|\| end < b->ranges[j].start) {
	/*
	* b exhausted, or
	* a: ----\|
	* b: \|----
	*/
	range_set_append(out, start, end);
	break;
	}
	if (start >= b->ranges[j].start) {
	/*
	* a: \|--????
	* b: \|------\|
	*/
	start = b->ranges[j].end;
	} else if (end > b->ranges[j].start) {
	/*
	* a: \|-----\|
	* b: \|--?????
	*/
	if (start < b->ranges[j].start)
	range_set_append(out, start, b->ranges[j].start);
	start = b->ranges[j].end;
	}
	}
	}
	}

	static void diff_ranges_init(struct diff_ranges *diff)
	{
	range_set_init(&diff->parent, 0);
	range_set_init(&diff->target, 0);
	}

	static void diff_ranges_release(struct diff_ranges *diff)
	{
	range_set_release(&diff->parent);
	range_set_release(&diff->target);
	}

	static void line_log_data_init(struct line_log_data *r)
	{
	memset(r, 0, sizeof(struct line_log_data));
	range_set_init(&r->ranges, 0);
	}

	static void line_log_data_clear(struct line_log_data *r)
	{
	range_set_release(&r->ranges);
	if (r->pair)
	diff_free_filepair(r->pair);
	}

	static void free_line_log_data(struct line_log_data *r)
	{
	while (r) {
	struct line_log_data *next = r->next;
	line_log_data_clear(r);
	free(r);
	r = next;
	}
	}

	static struct line_log_data *
	search_line_log_data(struct line_log_data list, const char path,
	struct line_log_data **insertion_point)
	{
	struct line_log_data *p = list;
	if (insertion_point)
	*insertion_point = NULL;
	while (p) {
	int cmp = strcmp(p->path, path);
	if (!cmp)
	return p;
	if (insertion_point && cmp < 0)
	*insertion_point = p;
	p = p->next;
	}
	return NULL;
	}

	/*
	* Note: takes ownership of 'path', which happens to be what the only
	* caller needs.
	*/
	static void line_log_data_insert(struct line_log_data **list,
	char *path,
	long begin, long end)
	{
	struct line_log_data *ip;
	struct line_log_data p = search_line_log_data(list, path, &ip);

	if (p) {
	range_set_append_unsafe(&p->ranges, begin, end);
	free(path);
	return;
	}

	CALLOC_ARRAY(p, 1);
	p->path = path;
	range_set_append(&p->ranges, begin, end);
	if (ip) {
	p->next = ip->next;
	ip->next = p;
	} else {
	p->next = *list;
	*list = p;
	}
	}

	struct collect_diff_cbdata {
	struct diff_ranges *diff;
	};

	static int collect_diff_cb(long start_a, long count_a,
	long start_b, long count_b,
	void *data)
	{
	struct collect_diff_cbdata *d = data;

	if (count_a >= 0)
	range_set_append(&d->diff->parent, start_a, start_a + count_a);
	if (count_b >= 0)
	range_set_append(&d->diff->target, start_b, start_b + count_b);

	return 0;
	}

	static int collect_diff(mmfile_t parent, mmfile_t target, struct diff_ranges *out)
	{
	struct collect_diff_cbdata cbdata = {NULL};
	xpparam_t xpp;
	xdemitconf_t xecfg;
	xdemitcb_t ecb;

	memset(&xpp, 0, sizeof(xpp));
	memset(&xecfg, 0, sizeof(xecfg));
	xecfg.ctxlen = xecfg.interhunkctxlen = 0;

	cbdata.diff = out;
	xecfg.hunk_func = collect_diff_cb;
	memset(&ecb, 0, sizeof(ecb));
	ecb.priv = &cbdata;
	return xdi_diff(parent, target, &xpp, &xecfg, &ecb);
	}

	/*
	* These are handy for debugging. Removing them with #if 0 silences
	* the "unused function" warning.
	*/
	#if 0
	static void dump_range_set(struct range_set rs, const char desc)
	{
	int i;
	printf("range set %s (%d items):\n", desc, rs->nr);
	for (i = 0; i < rs->nr; i++)
	printf("\t[%ld,%ld]\n", rs->ranges[i].start, rs->ranges[i].end);
	}

	static void dump_line_log_data(struct line_log_data *r)
	{
	char buf[4096];
	while (r) {
	snprintf(buf, 4096, "file %s\n", r->path);
	dump_range_set(&r->ranges, buf);
	r = r->next;
	}
	}

	static void dump_diff_ranges(struct diff_ranges diff, const char desc)
	{
	int i;
	assert(diff->parent.nr == diff->target.nr);
	printf("diff ranges %s (%d items):\n", desc, diff->parent.nr);
	printf("\tparent\ttarget\n");
	for (i = 0; i < diff->parent.nr; i++) {
	printf("\t[%ld,%ld]\t[%ld,%ld]\n",
	diff->parent.ranges[i].start,
	diff->parent.ranges[i].end,
	diff->target.ranges[i].start,
	diff->target.ranges[i].end);
	}
	}
	#endif


	static int ranges_overlap(struct range a, struct range b)
	{
	return !(a->end <= b->start \|\| b->end <= a->start);
	}

	/*
	* Given a diff and the set of interesting ranges, determine all hunks
	* of the diff which touch (overlap) at least one of the interesting
	* ranges in the target.
	*/
	static void diff_ranges_filter_touched(struct diff_ranges *out,
	struct diff_ranges *diff,
	struct range_set *rs)
	{
	unsigned int i, j = 0;

	assert(out->target.nr == 0);

	for (i = 0; i < diff->target.nr; i++) {
	while (diff->target.ranges[i].start > rs->ranges[j].end) {
	j++;
	if (j == rs->nr)
	return;
	}
	if (ranges_overlap(&diff->target.ranges[i], &rs->ranges[j])) {
	range_set_append(&out->parent,
	diff->parent.ranges[i].start,
	diff->parent.ranges[i].end);
	range_set_append(&out->target,
	diff->target.ranges[i].start,
	diff->target.ranges[i].end);
	}
	}
	}

	/*
	* Adjust the line counts in 'rs' to account for the lines
	* added/removed in the diff.
	*/
	static void range_set_shift_diff(struct range_set *out,
	struct range_set *rs,
	struct diff_ranges *diff)
	{
	unsigned int i, j = 0;
	long offset = 0;
	struct range *src = rs->ranges;
	struct range *target = diff->target.ranges;
	struct range *parent = diff->parent.ranges;

	for (i = 0; i < rs->nr; i++) {
	while (j < diff->target.nr && src[i].start >= target[j].start) {
	offset += (parent[j].end-parent[j].start)
	- (target[j].end-target[j].start);
	j++;
	}
	range_set_append(out, src[i].start+offset, src[i].end+offset);
	}
	}

	/*
	* Given a diff and the set of interesting ranges, map the ranges
	* across the diff. That is: observe that the target commit takes
	* blame for all the + (target-side) ranges. So for every pair of
	* ranges in the diff that was touched, we remove the latter and add
	* its parent side.
	*/
	static void range_set_map_across_diff(struct range_set *out,
	struct range_set *rs,
	struct diff_ranges *diff,
	struct diff_ranges **touched_out)
	{
	struct diff_ranges touched = xmalloc(sizeof(touched));
	struct range_set tmp1 = RANGE_SET_INIT;
	struct range_set tmp2 = RANGE_SET_INIT;

	diff_ranges_init(touched);
	diff_ranges_filter_touched(touched, diff, rs);
	range_set_difference(&tmp1, rs, &touched->target);
	range_set_shift_diff(&tmp2, &tmp1, diff);
	range_set_union(out, &tmp2, &touched->parent);
	range_set_release(&tmp1);
	range_set_release(&tmp2);

	*touched_out = touched;
	}

	static struct commit check_single_commit(struct rev_info revs)
	{
	struct object *commit = NULL;
	int found = -1;
	int i;

	for (i = 0; i < revs->pending.nr; i++) {
	struct object *obj = revs->pending.objects[i].item;
	if (obj->flags & UNINTERESTING)
	continue;
	obj = deref_tag(revs->repo, obj, NULL, 0);
	if (!obj \|\| obj->type != OBJ_COMMIT)
	die("Non commit %s?", revs->pending.objects[i].name);
	if (commit)
	die("More than one commit to dig from: %s and %s?",
	revs->pending.objects[i].name,
	revs->pending.objects[found].name);
	commit = obj;
	found = i;
	}

	if (!commit)
	die("No commit specified?");

	return (struct commit *) commit;
	}

	static void fill_blob_sha1(struct repository r, struct commit commit,
	struct diff_filespec *spec)
	{
	unsigned short mode;
	struct object_id oid;

	if (get_tree_entry(r, &commit->object.oid, spec->path, &oid, &mode))
	die("There is no path %s in the commit", spec->path);
	fill_filespec(spec, &oid, 1, mode);

	return;
	}

	static void fill_line_ends(struct repository *r,
	struct diff_filespec *spec,
	long *lines,
	unsigned long **line_ends)
	{
	int num = 0, size = 50;
	long cur = 0;
	unsigned long *ends = NULL;
	char *data = NULL;

	if (diff_populate_filespec(r, spec, NULL))
	die("Cannot read blob %s", oid_to_hex(&spec->oid));

	ALLOC_ARRAY(ends, size);
	ends[cur++] = 0;
	data = spec->data;
	while (num < spec->size) {
	if (data[num] == '\n' \|\| num == spec->size - 1) {
	ALLOC_GROW(ends, (cur + 1), size);
	ends[cur++] = num;
	}
	num++;
	}

	/* shrink the array to fit the elements */
	REALLOC_ARRAY(ends, cur);
	*lines = cur-1;
	*line_ends = ends;
	}

	struct nth_line_cb {
	struct diff_filespec *spec;
	long lines;
	unsigned long *line_ends;
	};

	static const char nth_line(void data, long line)
	{
	struct nth_line_cb *d = data;
	assert(d && line <= d->lines);
	assert(d->spec && d->spec->data);

	if (line == 0)
	return (char *)d->spec->data;
	else
	return (char *)d->spec->data + d->line_ends[line] + 1;
	}

	static struct line_log_data *
	parse_lines(struct repository r, struct commit commit,
	const char prefix, struct string_list args)
	{
	long lines = 0;
	unsigned long *ends = NULL;
	struct nth_line_cb cb_data;
	struct string_list_item *item;
	struct line_log_data *ranges = NULL;
	struct line_log_data *p;

	for_each_string_list_item(item, args) {
	const char name_part, range_part;
	char *full_name;
	struct diff_filespec *spec;
	long begin = 0, end = 0;
	long anchor;

	name_part = skip_range_arg(item->string, r->index);
	if (!name_part \|\| *name_part != ':' \|\| !name_part[1])
	die("-L argument not 'start,end:file' or ':funcname:file': %s",
	item->string);
	range_part = xstrndup(item->string, name_part - item->string);
	name_part++;

	full_name = prefix_path(prefix, prefix ? strlen(prefix) : 0,
	name_part);

	spec = alloc_filespec(full_name);
	fill_blob_sha1(r, commit, spec);
	fill_line_ends(r, spec, &lines, &ends);
	cb_data.spec = spec;
	cb_data.lines = lines;
	cb_data.line_ends = ends;

	p = search_line_log_data(ranges, full_name, NULL);
	if (p && p->ranges.nr)
	anchor = p->ranges.ranges[p->ranges.nr - 1].end + 1;
	else
	anchor = 1;

	if (parse_range_arg(range_part, nth_line, &cb_data,
	lines, anchor, &begin, &end,
	full_name, r->index))
	die("malformed -L argument '%s'", range_part);
	if ((!lines && (begin \|\| end)) \|\| lines < begin)
	die("file %s has only %lu lines", name_part, lines);
	if (begin < 1)
	begin = 1;
	if (end < 1 \|\| lines < end)
	end = lines;
	begin--;
	line_log_data_insert(&ranges, full_name, begin, end);

	free_filespec(spec);
	FREE_AND_NULL(ends);
	}

	for (p = ranges; p; p = p->next)
	sort_and_merge_range_set(&p->ranges);

	return ranges;
	}

	static struct line_log_data line_log_data_copy_one(struct line_log_data r)
	{
	struct line_log_data ret = xmalloc(sizeof(ret));

	assert(r);
	line_log_data_init(ret);
	range_set_copy(&ret->ranges, &r->ranges);

	ret->path = xstrdup(r->path);

	return ret;
	}

	static struct line_log_data *
	line_log_data_copy(struct line_log_data *r)
	{
	struct line_log_data *ret = NULL;
	struct line_log_data tmp = NULL, prev = NULL;

	assert(r);
	ret = tmp = prev = line_log_data_copy_one(r);
	r = r->next;
	while (r) {
	tmp = line_log_data_copy_one(r);
	prev->next = tmp;
	prev = tmp;
	r = r->next;
	}

	return ret;
	}

	/* merge two range sets across files */
	static struct line_log_data line_log_data_merge(struct line_log_data a,
	struct line_log_data *b)
	{
	struct line_log_data head = NULL, *pp = &head;

	while (a \|\| b) {
	struct line_log_data *src;
	struct line_log_data *src2 = NULL;
	struct line_log_data *d;
	int cmp;
	if (!a)
	cmp = 1;
	else if (!b)
	cmp = -1;
	else
	cmp = strcmp(a->path, b->path);
	if (cmp < 0) {
	src = a;
	a = a->next;
	} else if (cmp == 0) {
	src = a;
	a = a->next;
	src2 = b;
	b = b->next;
	} else {
	src = b;
	b = b->next;
	}
	d = xmalloc(sizeof(struct line_log_data));
	line_log_data_init(d);
	d->path = xstrdup(src->path);
	*pp = d;
	pp = &d->next;
	if (src2)
	range_set_union(&d->ranges, &src->ranges, &src2->ranges);
	else
	range_set_copy(&d->ranges, &src->ranges);
	}

	return head;
	}

	static void add_line_range(struct rev_info revs, struct commit commit,
	struct line_log_data *range)
	{
	struct line_log_data *old_line = NULL;
	struct line_log_data *new_line = NULL;

	old_line = lookup_decoration(&revs->line_log_data, &commit->object);
	if (old_line && range) {
	new_line = line_log_data_merge(old_line, range);
	free_line_log_data(old_line);
	} else if (range)
	new_line = line_log_data_copy(range);

	if (new_line)
	add_decoration(&revs->line_log_data, &commit->object, new_line);
	}

	static void clear_commit_line_range(struct rev_info revs, struct commit commit)
	{
	struct line_log_data *r;
	r = lookup_decoration(&revs->line_log_data, &commit->object);
	if (!r)
	return;
	free_line_log_data(r);
	add_decoration(&revs->line_log_data, &commit->object, NULL);
	}

	static struct line_log_data lookup_line_range(struct rev_info revs,
	struct commit *commit)
	{
	struct line_log_data *ret = NULL;
	struct line_log_data *d;

	ret = lookup_decoration(&revs->line_log_data, &commit->object);

	for (d = ret; d; d = d->next)
	range_set_check_invariants(&d->ranges);

	return ret;
	}

	static int same_paths_in_pathspec_and_range(struct pathspec *pathspec,
	struct line_log_data *range)
	{
	int i;
	struct line_log_data *r;

	for (i = 0, r = range; i < pathspec->nr && r; i++, r = r->next)
	if (strcmp(pathspec->items[i].match, r->path))
	return 0;
	if (i < pathspec->nr \|\| r)
	/* different number of pathspec items and ranges */
	return 0;

	return 1;
	}

	static void parse_pathspec_from_ranges(struct pathspec *pathspec,
	struct line_log_data *range)
	{
	struct line_log_data *r;
	struct strvec array = STRVEC_INIT;
	const char **paths;

	for (r = range; r; r = r->next)
	strvec_push(&array, r->path);
	paths = strvec_detach(&array);

	parse_pathspec(pathspec, 0, PATHSPEC_PREFER_FULL, "", paths);
	/* strings are now owned by pathspec */
	free(paths);
	}

	void line_log_init(struct rev_info rev, const char prefix, struct string_list *args)
	{
	struct commit *commit = NULL;
	struct line_log_data *range;

	commit = check_single_commit(rev);
	range = parse_lines(rev->diffopt.repo, commit, prefix, args);
	add_line_range(rev, commit, range);

	parse_pathspec_from_ranges(&rev->diffopt.pathspec, range);
	}

	static void move_diff_queue(struct diff_queue_struct *dst,
	struct diff_queue_struct *src)
	{
	assert(src != dst);
	memcpy(dst, src, sizeof(struct diff_queue_struct));
	DIFF_QUEUE_CLEAR(src);
	}

	static void filter_diffs_for_paths(struct line_log_data *range, int keep_deletions)
	{
	int i;
	struct diff_queue_struct outq;
	DIFF_QUEUE_CLEAR(&outq);

	for (i = 0; i < diff_queued_diff.nr; i++) {
	struct diff_filepair *p = diff_queued_diff.queue[i];
	struct line_log_data *rg = NULL;

	if (!DIFF_FILE_VALID(p->two)) {
	if (keep_deletions)
	diff_q(&outq, p);
	else
	diff_free_filepair(p);
	continue;
	}
	for (rg = range; rg; rg = rg->next) {
	if (!strcmp(rg->path, p->two->path))
	break;
	}
	if (rg)
	diff_q(&outq, p);
	else
	diff_free_filepair(p);
	}
	free(diff_queued_diff.queue);
	diff_queued_diff = outq;
	}

	static inline int diff_might_be_rename(void)
	{
	int i;
	for (i = 0; i < diff_queued_diff.nr; i++)
	if (!DIFF_FILE_VALID(diff_queued_diff.queue[i]->one)) {
	/* fprintf(stderr, "diff_might_be_rename found creation of: %s\n", */
	/* diff_queued_diff.queue[i]->two->path); */
	return 1;
	}
	return 0;
	}

	static void queue_diffs(struct line_log_data *range,
	struct diff_options *opt,
	struct diff_queue_struct *queue,
	struct commit commit, struct commit parent)
	{
	struct object_id tree_oid, parent_tree_oid;

	assert(commit);

	tree_oid = get_commit_tree_oid(commit);
	parent_tree_oid = parent ? get_commit_tree_oid(parent) : NULL;

	if (opt->detect_rename &&
	!same_paths_in_pathspec_and_range(&opt->pathspec, range)) {
	clear_pathspec(&opt->pathspec);
	parse_pathspec_from_ranges(&opt->pathspec, range);
	}
	DIFF_QUEUE_CLEAR(&diff_queued_diff);
	diff_tree_oid(parent_tree_oid, tree_oid, "", opt);
	if (opt->detect_rename && diff_might_be_rename()) {
	/* must look at the full tree diff to detect renames */
	clear_pathspec(&opt->pathspec);
	DIFF_QUEUE_CLEAR(&diff_queued_diff);

	diff_tree_oid(parent_tree_oid, tree_oid, "", opt);

	filter_diffs_for_paths(range, 1);
	diffcore_std(opt);
	filter_diffs_for_paths(range, 0);
	}
	move_diff_queue(queue, &diff_queued_diff);
	}

	static char get_nth_line(long line, unsigned long ends, void *data)
	{
	if (line == 0)
	return (char *)data;
	else
	return (char *)data + ends[line] + 1;
	}

	static void print_line(const char *prefix, char first,
	long line, unsigned long ends, void data,
	const char color, const char reset, FILE *file)
	{
	char *begin = get_nth_line(line, ends, data);
	char *end = get_nth_line(line+1, ends, data);
	int had_nl = 0;

	if (end > begin && end[-1] == '\n') {
	end--;
	had_nl = 1;
	}

	fputs(prefix, file);
	fputs(color, file);
	putc(first, file);
	fwrite(begin, 1, end-begin, file);
	fputs(reset, file);
	putc('\n', file);
	if (!had_nl)
	fputs("\\ No newline at end of file\n", file);
	}

	static char output_prefix(struct diff_options opt)
	{
	char *prefix = "";

	if (opt->output_prefix) {
	struct strbuf *sb = opt->output_prefix(opt, opt->output_prefix_data);
	prefix = sb->buf;
	}

	return prefix;
	}

	static void dump_diff_hacky_one(struct rev_info rev, struct line_log_data range)
	{
	unsigned int i, j = 0;
	long p_lines, t_lines;
	unsigned long p_ends = NULL, t_ends = NULL;
	struct diff_filepair *pair = range->pair;
	struct diff_ranges *diff = &range->diff;

	struct diff_options *opt = &rev->diffopt;
	char *prefix = output_prefix(opt);
	const char *c_reset = diff_get_color(opt->use_color, DIFF_RESET);
	const char *c_frag = diff_get_color(opt->use_color, DIFF_FRAGINFO);
	const char *c_meta = diff_get_color(opt->use_color, DIFF_METAINFO);
	const char *c_old = diff_get_color(opt->use_color, DIFF_FILE_OLD);
	const char *c_new = diff_get_color(opt->use_color, DIFF_FILE_NEW);
	const char *c_context = diff_get_color(opt->use_color, DIFF_CONTEXT);

	if (!pair \|\| !diff)
	return;

	if (pair->one->oid_valid)
	fill_line_ends(rev->diffopt.repo, pair->one, &p_lines, &p_ends);
	fill_line_ends(rev->diffopt.repo, pair->two, &t_lines, &t_ends);

	fprintf(opt->file, "%s%sdiff --git a/%s b/%s%s\n", prefix, c_meta, pair->one->path, pair->two->path, c_reset);
	fprintf(opt->file, "%s%s--- %s%s%s\n", prefix, c_meta,
	pair->one->oid_valid ? "a/" : "",
	pair->one->oid_valid ? pair->one->path : "/dev/null",
	c_reset);
	fprintf(opt->file, "%s%s+++ b/%s%s\n", prefix, c_meta, pair->two->path, c_reset);
	for (i = 0; i < range->ranges.nr; i++) {
	long p_start, p_end;
	long t_start = range->ranges.ranges[i].start;
	long t_end = range->ranges.ranges[i].end;
	long t_cur = t_start;
	unsigned int j_last;

	while (j < diff->target.nr && diff->target.ranges[j].end < t_start)
	j++;
	if (j == diff->target.nr \|\| diff->target.ranges[j].start > t_end)
	continue;

	/* Scan ahead to determine the last diff that falls in this range */
	j_last = j;
	while (j_last < diff->target.nr && diff->target.ranges[j_last].start < t_end)
	j_last++;
	if (j_last > j)
	j_last--;

	/*
	* Compute parent hunk headers: we know that the diff
	* has the correct line numbers (but not all hunks).
	* So it suffices to shift the start/end according to
	* the line numbers of the first/last hunk(s) that
	* fall in this range.
	*/
	if (t_start < diff->target.ranges[j].start)
	p_start = diff->parent.ranges[j].start - (diff->target.ranges[j].start-t_start);
	else
	p_start = diff->parent.ranges[j].start;
	if (t_end > diff->target.ranges[j_last].end)
	p_end = diff->parent.ranges[j_last].end + (t_end-diff->target.ranges[j_last].end);
	else
	p_end = diff->parent.ranges[j_last].end;

	if (!p_start && !p_end) {
	p_start = -1;
	p_end = -1;
	}

	/* Now output a diff hunk for this range */
	fprintf(opt->file, "%s%s@@ -%ld,%ld +%ld,%ld @@%s\n",
	prefix, c_frag,
	p_start+1, p_end-p_start, t_start+1, t_end-t_start,
	c_reset);
	while (j < diff->target.nr && diff->target.ranges[j].start < t_end) {
	int k;
	for (; t_cur < diff->target.ranges[j].start; t_cur++)
	print_line(prefix, ' ', t_cur, t_ends, pair->two->data,
	c_context, c_reset, opt->file);
	for (k = diff->parent.ranges[j].start; k < diff->parent.ranges[j].end; k++)
	print_line(prefix, '-', k, p_ends, pair->one->data,
	c_old, c_reset, opt->file);
	for (; t_cur < diff->target.ranges[j].end && t_cur < t_end; t_cur++)
	print_line(prefix, '+', t_cur, t_ends, pair->two->data,
	c_new, c_reset, opt->file);
	j++;
	}
	for (; t_cur < t_end; t_cur++)
	print_line(prefix, ' ', t_cur, t_ends, pair->two->data,
	c_context, c_reset, opt->file);
	}

	free(p_ends);
	free(t_ends);
	}

	/*
	* NEEDSWORK: manually building a diff here is not the Right
	* Thing(tm). log -L should be built into the diff pipeline.
	*/
	static void dump_diff_hacky(struct rev_info rev, struct line_log_data range)
	{
	fprintf(rev->diffopt.file, "%s\n", output_prefix(&rev->diffopt));
	while (range) {
	dump_diff_hacky_one(rev, range);
	range = range->next;
	}
	}

	/*
	* Unlike most other functions, this destructively operates on
	* 'range'.
	*/
	static int process_diff_filepair(struct rev_info *rev,
	struct diff_filepair *pair,
	struct line_log_data *range,
	struct diff_ranges **diff_out)
	{
	struct line_log_data *rg = range;
	struct range_set tmp;
	struct diff_ranges diff;
	mmfile_t file_parent, file_target;

	assert(pair->two->path);
	while (rg) {
	assert(rg->path);
	if (!strcmp(rg->path, pair->two->path))
	break;
	rg = rg->next;
	}

	if (!rg)
	return 0;
	if (rg->ranges.nr == 0)
	return 0;

	assert(pair->two->oid_valid);
	diff_populate_filespec(rev->diffopt.repo, pair->two, NULL);
	file_target.ptr = pair->two->data;
	file_target.size = pair->two->size;

	if (pair->one->oid_valid) {
	diff_populate_filespec(rev->diffopt.repo, pair->one, NULL);
	file_parent.ptr = pair->one->data;
	file_parent.size = pair->one->size;
	} else {
	file_parent.ptr = "";
	file_parent.size = 0;
	}

	diff_ranges_init(&diff);
	if (collect_diff(&file_parent, &file_target, &diff))
	die("unable to generate diff for %s", pair->one->path);

	/* NEEDSWORK should apply some heuristics to prevent mismatches */
	free(rg->path);
	rg->path = xstrdup(pair->one->path);

	range_set_init(&tmp, 0);
	range_set_map_across_diff(&tmp, &rg->ranges, &diff, diff_out);
	range_set_release(&rg->ranges);
	range_set_move(&rg->ranges, &tmp);

	diff_ranges_release(&diff);

	return ((*diff_out)->parent.nr > 0);
	}

	static struct diff_filepair diff_filepair_dup(struct diff_filepair pair)
	{
	struct diff_filepair *new_filepair = xmalloc(sizeof(struct diff_filepair));
	new_filepair->one = pair->one;
	new_filepair->two = pair->two;
	new_filepair->one->count++;
	new_filepair->two->count++;
	return new_filepair;
	}

	static void free_diffqueues(int n, struct diff_queue_struct *dq)
	{
	int i, j;
	for (i = 0; i < n; i++)
	for (j = 0; j < dq[i].nr; j++)
	diff_free_filepair(dq[i].queue[j]);
	free(dq);
	}

	static int process_all_files(struct line_log_data **range_out,
	struct rev_info *rev,
	struct diff_queue_struct *queue,
	struct line_log_data *range)
	{
	int i, changed = 0;

	*range_out = line_log_data_copy(range);

	for (i = 0; i < queue->nr; i++) {
	struct diff_ranges *pairdiff = NULL;
	struct diff_filepair *pair = queue->queue[i];
	if (process_diff_filepair(rev, pair, *range_out, &pairdiff)) {
	/*
	* Store away the diff for later output. We
	* tuck it in the ranges we got as _input_,
	* since that's the commit that caused the
	* diff.
	*
	* NEEDSWORK not enough when we get around to
	* doing something interesting with merges;
	* currently each invocation on a merge parent
	* trashes the previous one's diff.
	*
	* NEEDSWORK tramples over data structures not owned here
	*/
	struct line_log_data *rg = range;
	changed++;
	while (rg && strcmp(rg->path, pair->two->path))
	rg = rg->next;
	assert(rg);
	rg->pair = diff_filepair_dup(queue->queue[i]);
	memcpy(&rg->diff, pairdiff, sizeof(struct diff_ranges));
	}
	free(pairdiff);
	}

	return changed;
	}

	int line_log_print(struct rev_info rev, struct commit commit)
	{

	show_log(rev);
	if (!(rev->diffopt.output_format & DIFF_FORMAT_NO_OUTPUT)) {
	struct line_log_data *range = lookup_line_range(rev, commit);
	dump_diff_hacky(rev, range);
	}
	return 1;
	}

	static int bloom_filter_check(struct rev_info *rev,
	struct commit *commit,
	struct line_log_data *range)
	{
	struct bloom_filter *filter;
	struct bloom_key key;
	int result = 0;

	if (!commit->parents)
	return 1;

	if (!rev->bloom_filter_settings \|\|
	!(filter = get_bloom_filter(rev->repo, commit)))
	return 1;

	if (!range)
	return 0;

	while (!result && range) {
	fill_bloom_key(range->path, strlen(range->path), &key, rev->bloom_filter_settings);

	if (bloom_filter_contains(filter, &key, rev->bloom_filter_settings))
	result = 1;

	clear_bloom_key(&key);
	range = range->next;
	}

	return result;
	}

	static int process_ranges_ordinary_commit(struct rev_info rev, struct commit commit,
	struct line_log_data *range)
	{
	struct commit *parent = NULL;
	struct diff_queue_struct queue;
	struct line_log_data *parent_range;
	int changed;

	if (commit->parents)
	parent = commit->parents->item;

	queue_diffs(range, &rev->diffopt, &queue, commit, parent);
	changed = process_all_files(&parent_range, rev, &queue, range);

	if (parent)
	add_line_range(rev, parent, parent_range);
	free_line_log_data(parent_range);
	return changed;
	}

	static int process_ranges_merge_commit(struct rev_info rev, struct commit commit,
	struct line_log_data *range)
	{
	struct diff_queue_struct *diffqueues;
	struct line_log_data **cand;
	struct commit **parents;
	struct commit_list *p;
	int i;
	int nparents = commit_list_count(commit->parents);

	if (nparents > 1 && rev->first_parent_only)
	nparents = 1;

	ALLOC_ARRAY(diffqueues, nparents);
	ALLOC_ARRAY(cand, nparents);
	ALLOC_ARRAY(parents, nparents);

	p = commit->parents;
	for (i = 0; i < nparents; i++) {
	parents[i] = p->item;
	p = p->next;
	queue_diffs(range, &rev->diffopt, &diffqueues[i], commit, parents[i]);
	}

	for (i = 0; i < nparents; i++) {
	int changed;
	cand[i] = NULL;
	changed = process_all_files(&cand[i], rev, &diffqueues[i], range);
	if (!changed) {
	/*
	* This parent can take all the blame, so we
	* don't follow any other path in history
	*/
	add_line_range(rev, parents[i], cand[i]);
	clear_commit_line_range(rev, commit);
	commit_list_append(parents[i], &commit->parents);
	free(parents);
	free(cand);
	free_diffqueues(nparents, diffqueues);
	/* NEEDSWORK leaking like a sieve */
	return 0;
	}
	}

	/*
	* No single parent took the blame. We add the candidates
	* from the above loop to the parents.
	*/
	for (i = 0; i < nparents; i++) {
	add_line_range(rev, parents[i], cand[i]);
	}

	clear_commit_line_range(rev, commit);
	free(parents);
	free(cand);
	free_diffqueues(nparents, diffqueues);
	return 1;

	/* NEEDSWORK evil merge detection stuff */
	/* NEEDSWORK leaking like a sieve */
	}

	int line_log_process_ranges_arbitrary_commit(struct rev_info rev, struct commit commit)
	{
	struct line_log_data *range = lookup_line_range(rev, commit);
	int changed = 0;

	if (range) {
	if (commit->parents && !bloom_filter_check(rev, commit, range)) {
	struct line_log_data *prange = line_log_data_copy(range);
	add_line_range(rev, commit->parents->item, prange);
	clear_commit_line_range(rev, commit);
	} else if (!commit->parents \|\| !commit->parents->next)
	changed = process_ranges_ordinary_commit(rev, commit, range);
	else
	changed = process_ranges_merge_commit(rev, commit, range);
	}

	if (!changed)
	commit->object.flags \|= TREESAME;

	return changed;
	}

	static enum rewrite_result line_log_rewrite_one(struct rev_info rev, struct commit *pp)
	{
	for (;;) {
	struct commit p = pp;
	if (p->parents && p->parents->next)
	return rewrite_one_ok;
	if (p->object.flags & UNINTERESTING)
	return rewrite_one_ok;
	if (!(p->object.flags & TREESAME))
	return rewrite_one_ok;
	if (!p->parents)
	return rewrite_one_noparents;
	*pp = p->parents->item;
	}
	}

	int line_log_filter(struct rev_info *rev)
	{
	struct commit *commit;
	struct commit_list *list = rev->commits;
	struct commit_list out = NULL, *pp = &out;

	while (list) {
	struct commit_list *to_free = NULL;
	commit = list->item;
	if (line_log_process_ranges_arbitrary_commit(rev, commit)) {
	*pp = list;
	pp = &list->next;
	} else
	to_free = list;
	list = list->next;
	free(to_free);
	}
	*pp = NULL;

	for (list = out; list; list = list->next)
	rewrite_parents(rev, list->item, line_log_rewrite_one);

	rev->commits = out;

	return 0;
	}

git / git

git/line-log.c