Merge pull request #4489 from libgit2/ethomson/conflicts_crlf

Conflict markers should match EOL style in conflicting files

17 files changed, 326 insertions, 133 deletions

diff --git a/src/common.h b/src/common.h
index 5fb4a608f..44063be12 100644
--- a/src/common.h
+++ b/src/common.h
@@ -230,6 +230,12 @@ GIT_INLINE(void) git__init_structure(void *structure, size_t len, unsigned int v
 		GIT_ADD_SIZET_OVERFLOW(out, *(out), three) || \
 		GIT_ADD_SIZET_OVERFLOW(out, *(out), four)) { return -1; }
 
+#define GITERR_CHECK_ALLOC_ADD5(out, one, two, three, four, five) \
+	if (GIT_ADD_SIZET_OVERFLOW(out, one, two) || \
+		GIT_ADD_SIZET_OVERFLOW(out, *(out), three) || \
+		GIT_ADD_SIZET_OVERFLOW(out, *(out), four) || \
+		GIT_ADD_SIZET_OVERFLOW(out, *(out), five)) { return -1; }
+
 /** Check for multiplicative overflow, failing if it would occur. */
 #define GITERR_CHECK_ALLOC_MULTIPLY(out, nelem, elsize) \
 	if (GIT_MULTIPLY_SIZET_OVERFLOW(out, nelem, elsize)) { return -1; }
diff --git a/src/xdiff/xdiff.h b/src/xdiff/xdiff.h
index b7dc05697..5b13e77a0 100644
--- a/src/xdiff/xdiff.h
+++ b/src/xdiff/xdiff.h
@@ -13,15 +13,13 @@
  *  Lesser General Public License for more details.
  *
  *  You should have received a copy of the GNU Lesser General Public
- *  License along with this library; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *  License along with this library; if not, see
+ *  <http://www.gnu.org/licenses/>.
  *
  *  Davide Libenzi <davidel@xmailserver.org>
  *
  */
 
-#include "../util.h"
-
 #if !defined(XDIFF_H)
 #define XDIFF_H
 
@@ -29,24 +27,29 @@
 extern "C" {
 #endif /* #ifdef __cplusplus */
 
+/* xpparm_t.flags */
+#define XDF_NEED_MINIMAL (1 << 0)
+
+#define XDF_IGNORE_WHITESPACE (1 << 1)
+#define XDF_IGNORE_WHITESPACE_CHANGE (1 << 2)
+#define XDF_IGNORE_WHITESPACE_AT_EOL (1 << 3)
+#define XDF_IGNORE_CR_AT_EOL (1 << 4)
+#define XDF_WHITESPACE_FLAGS (XDF_IGNORE_WHITESPACE | \
+			      XDF_IGNORE_WHITESPACE_CHANGE | \
+			      XDF_IGNORE_WHITESPACE_AT_EOL | \
+			      XDF_IGNORE_CR_AT_EOL)
 
-#define XDF_NEED_MINIMAL (1 << 1)
-#define XDF_IGNORE_WHITESPACE (1 << 2)
-#define XDF_IGNORE_WHITESPACE_CHANGE (1 << 3)
-#define XDF_IGNORE_WHITESPACE_AT_EOL (1 << 4)
-#define XDF_WHITESPACE_FLAGS (XDF_IGNORE_WHITESPACE | XDF_IGNORE_WHITESPACE_CHANGE | XDF_IGNORE_WHITESPACE_AT_EOL)
+#define XDF_IGNORE_BLANK_LINES (1 << 7)
 
-#define XDF_PATIENCE_DIFF (1 << 5)
-#define XDF_HISTOGRAM_DIFF (1 << 6)
+#define XDF_PATIENCE_DIFF (1 << 14)
+#define XDF_HISTOGRAM_DIFF (1 << 15)
 #define XDF_DIFF_ALGORITHM_MASK (XDF_PATIENCE_DIFF | XDF_HISTOGRAM_DIFF)
 #define XDF_DIFF_ALG(x) ((x) & XDF_DIFF_ALGORITHM_MASK)
 
-#define XDF_IGNORE_BLANK_LINES (1 << 7)
-
-#define XDF_INDENT_HEURISTIC (1 << 8)
+#define XDF_INDENT_HEURISTIC (1 << 23)
 
+/* xdemitconf_t.flags */
 #define XDL_EMIT_FUNCNAMES (1 << 0)
-#define XDL_EMIT_COMMON (1 << 1)
 #define XDL_EMIT_FUNCCONTEXT (1 << 2)
 
 #define XDL_MMB_READONLY (1 << 0)
@@ -83,6 +86,10 @@ typedef struct s_mmbuffer {
 
 typedef struct s_xpparam {
 	unsigned long flags;
+
+	/* See Documentation/diff-options.txt. */
+	char **anchors;
+	size_t anchors_nr;
 } xpparam_t;
 
 typedef struct s_xdemitcb {
diff --git a/src/xdiff/xdiffi.c b/src/xdiff/xdiffi.c
index 3e65b6ce5..3a71ef678 100644
--- a/src/xdiff/xdiffi.c
+++ b/src/xdiff/xdiffi.c
@@ -13,15 +13,14 @@
  *  Lesser General Public License for more details.
  *
  *  You should have received a copy of the GNU Lesser General Public
- *  License along with this library; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *  License along with this library; if not, see
+ *  <http://www.gnu.org/licenses/>.
  *
  *  Davide Libenzi <davidel@xmailserver.org>
  *
  */
 
 #include "xinclude.h"
-#include "common.h"
 #include "integer.h"
 
 
diff --git a/src/xdiff/xdiffi.h b/src/xdiff/xdiffi.h
index 8b81206c9..8f1c7c8b0 100644
--- a/src/xdiff/xdiffi.h
+++ b/src/xdiff/xdiffi.h
@@ -13,8 +13,8 @@
  *  Lesser General Public License for more details.
  *
  *  You should have received a copy of the GNU Lesser General Public
- *  License along with this library; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *  License along with this library; if not, see
+ *  <http://www.gnu.org/licenses/>.
  *
  *  Davide Libenzi <davidel@xmailserver.org>
  *
diff --git a/src/xdiff/xemit.c b/src/xdiff/xemit.c
index 600fd1fdd..0ffa6553a 100644
--- a/src/xdiff/xemit.c
+++ b/src/xdiff/xemit.c
@@ -13,8 +13,8 @@
  *  Lesser General Public License for more details.
  *
  *  You should have received a copy of the GNU Lesser General Public
- *  License along with this library; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *  License along with this library; if not, see
+ *  <http://www.gnu.org/licenses/>.
  *
  *  Davide Libenzi <davidel@xmailserver.org>
  *
@@ -22,15 +22,6 @@
 
 #include "xinclude.h"
 
-
-
-
-static long xdl_get_rec(xdfile_t *xdf, long ri, char const **rec);
-static int xdl_emit_record(xdfile_t *xdf, long ri, char const *pre, xdemitcb_t *ecb);
-
-
-
-
 static long xdl_get_rec(xdfile_t *xdf, long ri, char const **rec) {
 
 	*rec = xdf->recs[ri]->ptr;
@@ -110,7 +101,7 @@ static long def_ff(const char *rec, long len, char *buf, long sz, void *priv)
 
 	if (len > 0 &&
 			(isalpha((unsigned char)*rec) || /* identifier? */
-			 *rec == '_' ||	/* also identifier? */
+			 *rec == '_' || /* also identifier? */
 			 *rec == '$')) { /* identifiers from VMS and other esoterico */
 		if (len > sz)
 			len = sz;
@@ -122,22 +113,20 @@ static long def_ff(const char *rec, long len, char *buf, long sz, void *priv)
 	return -1;
 }
 
-static int xdl_emit_common(xdfenv_t *xe, xdchange_t *xscr, xdemitcb_t *ecb,
-                           xdemitconf_t const *xecfg) {
-	xdfile_t *xdf = &xe->xdf2;
-	const char *rchg = xdf->rchg;
-	long ix;
-
-	(void)xscr;
-	(void)xecfg;
+static long match_func_rec(xdfile_t *xdf, xdemitconf_t const *xecfg, long ri,
+			   char *buf, long sz)
+{
+	const char *rec;
+	long len = xdl_get_rec(xdf, ri, &rec);
+	if (!xecfg->find_func)
+		return def_ff(rec, len, buf, sz, xecfg->find_func_priv);
+	return xecfg->find_func(rec, len, buf, sz, xecfg->find_func_priv);
+}
 
-	for (ix = 0; ix < xdf->nrec; ix++) {
-		if (rchg[ix])
-			continue;
-		if (xdl_emit_record(xdf, ix, "", ecb))
-			return -1;
-	}
-	return 0;
+static int is_func_rec(xdfile_t *xdf, xdemitconf_t const *xecfg, long ri)
+{
+	char dummy[1];
+	return match_func_rec(xdf, xecfg, ri, dummy, sizeof(dummy)) >= 0;
 }
 
 struct func_line {
@@ -148,7 +137,6 @@ struct func_line {
 static long get_func_line(xdfenv_t *xe, xdemitconf_t const *xecfg,
 			  struct func_line *func_line, long start, long limit)
 {
-	find_func_t ff = xecfg->find_func ? xecfg->find_func : def_ff;
 	long l, size, step = (start > limit) ? -1 : 1;
 	char *buf, dummy[1];
 
@@ -156,9 +144,7 @@ static long get_func_line(xdfenv_t *xe, xdemitconf_t const *xecfg,
 	size = func_line ? sizeof(func_line->buf) : sizeof(dummy);
 
 	for (l = start; l != limit && 0 <= l && l < xe->xdf1.nrec; l += step) {
-		const char *rec;
-		long reclen = xdl_get_rec(&xe->xdf1, l, &rec);
-		long len = ff(rec, reclen, buf, size, xecfg->find_func_priv);
+		long len = match_func_rec(&xe->xdf1, xecfg, l, buf, size);
 		if (len >= 0) {
 			if (func_line)
 				func_line->len = len;
@@ -168,6 +154,18 @@ static long get_func_line(xdfenv_t *xe, xdemitconf_t const *xecfg,
 	return -1;
 }
 
+static int is_empty_rec(xdfile_t *xdf, long ri)
+{
+	const char *rec;
+	long len = xdl_get_rec(xdf, ri, &rec);
+
+	while (len > 0 && XDL_ISSPACE(*rec)) {
+		rec++;
+		len--;
+	}
+	return !len;
+}
+
 int xdl_emit_diff(xdfenv_t *xe, xdchange_t *xscr, xdemitcb_t *ecb,
 		  xdemitconf_t const *xecfg) {
 	long s1, s2, e1, e2, lctx;
@@ -175,9 +173,6 @@ int xdl_emit_diff(xdfenv_t *xe, xdchange_t *xscr, xdemitcb_t *ecb,
 	long funclineprev = -1;
 	struct func_line func_line = { 0 };
 
-	if (xecfg->flags & XDL_EMIT_COMMON)
-		return xdl_emit_common(xe, xscr, ecb, xecfg);
-
 	for (xch = xscr; xch; xch = xche->next) {
 		xche = xdl_get_hunk(&xch, xecfg);
 		if (!xch)
@@ -187,7 +182,33 @@ int xdl_emit_diff(xdfenv_t *xe, xdchange_t *xscr, xdemitcb_t *ecb,
 		s2 = XDL_MAX(xch->i2 - xecfg->ctxlen, 0);
 
 		if (xecfg->flags & XDL_EMIT_FUNCCONTEXT) {
-			long fs1 = get_func_line(xe, xecfg, NULL, xch->i1, -1);
+			long fs1, i1 = xch->i1;
+
+			/* Appended chunk? */
+			if (i1 >= xe->xdf1.nrec) {
+				long i2 = xch->i2;
+
+				/*
+				 * We don't need additional context if
+				 * a whole function was added.
+				 */
+				while (i2 < xe->xdf2.nrec) {
+					if (is_func_rec(&xe->xdf2, xecfg, i2))
+						goto post_context_calculation;
+					i2++;
+				}
+
+				/*
+				 * Otherwise get more context from the
+				 * pre-image.
+				 */
+				i1 = xe->xdf1.nrec - 1;
+			}
+
+			fs1 = get_func_line(xe, xecfg, NULL, i1, -1);
+			while (fs1 > 0 && !is_empty_rec(&xe->xdf1, fs1 - 1) &&
+			       !is_func_rec(&xe->xdf1, xecfg, fs1 - 1))
+				fs1--;
 			if (fs1 < 0)
 				fs1 = 0;
 			if (fs1 < s1) {
@@ -196,7 +217,7 @@ int xdl_emit_diff(xdfenv_t *xe, xdchange_t *xscr, xdemitcb_t *ecb,
 			}
 		}
 
- again:
+ post_context_calculation:
 		lctx = xecfg->ctxlen;
 		lctx = XDL_MIN(lctx, xe->xdf1.nrec - (xche->i1 + xche->chg1));
 		lctx = XDL_MIN(lctx, xe->xdf2.nrec - (xche->i2 + xche->chg2));
@@ -208,6 +229,8 @@ int xdl_emit_diff(xdfenv_t *xe, xdchange_t *xscr, xdemitcb_t *ecb,
 			long fe1 = get_func_line(xe, xecfg, NULL,
 						 xche->i1 + xche->chg1,
 						 xe->xdf1.nrec);
+			while (fe1 > 0 && is_empty_rec(&xe->xdf1, fe1 - 1))
+				fe1--;
 			if (fe1 < 0)
 				fe1 = xe->xdf1.nrec;
 			if (fe1 > e1) {
@@ -221,11 +244,12 @@ int xdl_emit_diff(xdfenv_t *xe, xdchange_t *xscr, xdemitcb_t *ecb,
 			 * its new end.
 			 */
 			if (xche->next) {
-				long l = xche->next->i1;
-				if (l <= e1 ||
+				long l = XDL_MIN(xche->next->i1,
+						 xe->xdf1.nrec - 1);
+				if (l - xecfg->ctxlen <= e1 ||
 				    get_func_line(xe, xecfg, NULL, l, e1) < 0) {
 					xche = xche->next;
-					goto again;
+					goto post_context_calculation;
 				}
 			}
 		}
diff --git a/src/xdiff/xemit.h b/src/xdiff/xemit.h
index d29710770..1b9887e67 100644
--- a/src/xdiff/xemit.h
+++ b/src/xdiff/xemit.h
@@ -13,8 +13,8 @@
  *  Lesser General Public License for more details.
  *
  *  You should have received a copy of the GNU Lesser General Public
- *  License along with this library; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *  License along with this library; if not, see
+ *  <http://www.gnu.org/licenses/>.
  *
  *  Davide Libenzi <davidel@xmailserver.org>
  *
diff --git a/src/xdiff/xhistogram.c b/src/xdiff/xhistogram.c
index 0c2edb89c..ca8605e31 100644
--- a/src/xdiff/xhistogram.c
+++ b/src/xdiff/xhistogram.c
@@ -44,7 +44,6 @@
 #include "xinclude.h"
 #include "xtypes.h"
 #include "xdiff.h"
-#include "common.h"
 
 #define MAX_PTR	UINT_MAX
 #define MAX_CNT	UINT_MAX
diff --git a/src/xdiff/xinclude.h b/src/xdiff/xinclude.h
index 4a1cde909..068ce42f8 100644
--- a/src/xdiff/xinclude.h
+++ b/src/xdiff/xinclude.h
@@ -13,8 +13,8 @@
  *  Lesser General Public License for more details.
  *
  *  You should have received a copy of the GNU Lesser General Public
- *  License along with this library; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *  License along with this library; if not, see
+ *  <http://www.gnu.org/licenses/>.
  *
  *  Davide Libenzi <davidel@xmailserver.org>
  *
@@ -42,5 +42,6 @@
 #include "xdiffi.h"
 #include "xemit.h"
 
+#include "common.h"
 
 #endif /* #if !defined(XINCLUDE_H) */
diff --git a/src/xdiff/xmacros.h b/src/xdiff/xmacros.h
index 165a895a9..2809a28ca 100644
--- a/src/xdiff/xmacros.h
+++ b/src/xdiff/xmacros.h
@@ -13,8 +13,8 @@
  *  Lesser General Public License for more details.
  *
  *  You should have received a copy of the GNU Lesser General Public
- *  License along with this library; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *  License along with this library; if not, see
+ *  <http://www.gnu.org/licenses/>.
  *
  *  Davide Libenzi <davidel@xmailserver.org>
  *
diff --git a/src/xdiff/xmerge.c b/src/xdiff/xmerge.c
index 6448b5542..6fec95aa3 100644
--- a/src/xdiff/xmerge.c
+++ b/src/xdiff/xmerge.c
@@ -13,15 +13,14 @@
  *  Lesser General Public License for more details.
  *
  *  You should have received a copy of the GNU Lesser General Public
- *  License along with this library; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *  License along with this library; if not, see
+ *  <http://www.gnu.org/licenses/>.
  *
  *  Davide Libenzi <davidel@xmailserver.org>
  *
  */
 
 #include "xinclude.h"
-#include "common.h"
 
 typedef struct s_xdmerge {
 	struct s_xdmerge *next;
@@ -110,7 +109,7 @@ static int xdl_merge_cmp_lines(xdfenv_t *xe1, int i1, xdfenv_t *xe2, int i2,
 	return 0;
 }
 
-static int xdl_recs_copy_0(size_t *out, int use_orig, xdfenv_t *xe, int i, int count, int add_nl, char *dest)
+static int xdl_recs_copy_0(size_t *out, int use_orig, xdfenv_t *xe, int i, int count, int needs_cr, int add_nl, char *dest)
 {
 	xrecord_t **recs;
 	size_t size = 0;
@@ -132,6 +131,12 @@ static int xdl_recs_copy_0(size_t *out, int use_orig, xdfenv_t *xe, int i, int c
 	if (add_nl) {
 		i = recs[count - 1]->size;
 		if (i == 0 || recs[count - 1]->ptr[i - 1] != '\n') {
+			if (needs_cr) {
+				if (dest)
+					dest[size] = '\r';
+				GITERR_CHECK_ALLOC_ADD(&size, size, 1);
+			}
+
 			if (dest)
 				dest[size] = '\n';
 
@@ -143,14 +148,58 @@ static int xdl_recs_copy_0(size_t *out, int use_orig, xdfenv_t *xe, int i, int c
 	return 0;
 }
 
-static int xdl_recs_copy(size_t *out, xdfenv_t *xe, int i, int count, int add_nl, char *dest)
+static int xdl_recs_copy(size_t *out, xdfenv_t *xe, int i, int count, int needs_cr, int add_nl, char *dest)
 {
-	return xdl_recs_copy_0(out, 0, xe, i, count, add_nl, dest);
+	return xdl_recs_copy_0(out, 0, xe, i, count, needs_cr, add_nl, dest);
 }
 
-static int xdl_orig_copy(size_t *out, xdfenv_t *xe, int i, int count, int add_nl, char *dest)
+static int xdl_orig_copy(size_t *out, xdfenv_t *xe, int i, int count, int needs_cr, int add_nl, char *dest)
 {
-	return xdl_recs_copy_0(out, 1, xe, i, count, add_nl, dest);
+	return xdl_recs_copy_0(out, 1, xe, i, count, needs_cr, add_nl, dest);
+}
+
+/*
+ * Returns 1 if the i'th line ends in CR/LF (if it is the last line and
+ * has no eol, the preceding line, if any), 0 if it ends in LF-only, and
+ * -1 if the line ending cannot be determined.
+ */
+static int is_eol_crlf(xdfile_t *file, int i)
+{
+	long size;
+
+	if (i < file->nrec - 1)
+		/* All lines before the last *must* end in LF */
+		return (size = file->recs[i]->size) > 1 &&
+			file->recs[i]->ptr[size - 2] == '\r';
+	if (!file->nrec)
+		/* Cannot determine eol style from empty file */
+		return -1;
+	if ((size = file->recs[i]->size) &&
+			file->recs[i]->ptr[size - 1] == '\n')
+		/* Last line; ends in LF; Is it CR/LF? */
+		return size > 1 &&
+			file->recs[i]->ptr[size - 2] == '\r';
+	if (!i)
+		/* The only line has no eol */
+		return -1;
+	/* Determine eol from second-to-last line */
+	return (size = file->recs[i - 1]->size) > 1 &&
+		file->recs[i - 1]->ptr[size - 2] == '\r';
+}
+
+static int is_cr_needed(xdfenv_t *xe1, xdfenv_t *xe2, xdmerge_t *m)
+{
+	int needs_cr;
+
+	/* Match post-images' preceding, or first, lines' end-of-line style */
+	needs_cr = is_eol_crlf(&xe1->xdf2, m->i1 ? m->i1 - 1 : 0);
+	if (needs_cr)
+		needs_cr = is_eol_crlf(&xe2->xdf2, m->i2 ? m->i2 - 1 : 0);
+	/* Look at pre-image's first line, unless we already settled on LF */
+	if (needs_cr)
+		needs_cr = is_eol_crlf(&xe1->xdf1, 0);
+	/* If still undecided, use LF-only */
+	return needs_cr < 0 ? 0 : needs_cr;
 }
 
 static int fill_conflict_hunk(size_t *out, xdfenv_t *xe1, const char *name1,
@@ -162,6 +211,7 @@ static int fill_conflict_hunk(size_t *out, xdfenv_t *xe1, const char *name1,
 	int marker1_size = (name1 ? (int)strlen(name1) + 1 : 0);
 	int marker2_size = (name2 ? (int)strlen(name2) + 1 : 0);
 	int marker3_size = (name3 ? (int)strlen(name3) + 1 : 0);
+	int needs_cr = is_cr_needed(xe1, xe2, m);
 	size_t copied;
 
 	*out = 0;
@@ -170,14 +220,14 @@ static int fill_conflict_hunk(size_t *out, xdfenv_t *xe1, const char *name1,
 		marker_size = DEFAULT_CONFLICT_MARKER_SIZE;
 
 	/* Before conflicting part */
-	if (xdl_recs_copy(&copied, xe1, i, m->i1 - i, 0,
+	if (xdl_recs_copy(&copied, xe1, i, m->i1 - i, 0, 0,
 			      dest ? dest + size : NULL) < 0)
 		return -1;
 
 	GITERR_CHECK_ALLOC_ADD(&size, size, copied);
 
 	if (!dest) {
-		GITERR_CHECK_ALLOC_ADD4(&size, size, marker_size, 1, marker1_size);
+		GITERR_CHECK_ALLOC_ADD5(&size, size, marker_size, 1, needs_cr,  marker1_size);
 	} else {
 		memset(dest + size, '<', marker_size);
 		size += marker_size;
@@ -186,11 +236,13 @@ static int fill_conflict_hunk(size_t *out, xdfenv_t *xe1, const char *name1,
 			memcpy(dest + size + 1, name1, marker1_size - 1);
 			size += marker1_size;
 		}
+		if (needs_cr)
+			dest[size++] = '\r';
 		dest[size++] = '\n';
 	}
 
 	/* Postimage from side #1 */
-	if (xdl_recs_copy(&copied, xe1, m->i1, m->chg1, 1,
+	if (xdl_recs_copy(&copied, xe1, m->i1, m->chg1, needs_cr, 1,
 			      dest ? dest + size : NULL) < 0)
 		return -1;
 
@@ -199,7 +251,7 @@ static int fill_conflict_hunk(size_t *out, xdfenv_t *xe1, const char *name1,
 	if (style == XDL_MERGE_DIFF3) {
 		/* Shared preimage */
 		if (!dest) {
-			GITERR_CHECK_ALLOC_ADD4(&size, size, marker_size, 1, marker3_size);
+			GITERR_CHECK_ALLOC_ADD5(&size, size, marker_size, 1, needs_cr, marker3_size);
 		} else {
 			memset(dest + size, '|', marker_size);
 			size += marker_size;
@@ -208,32 +260,36 @@ static int fill_conflict_hunk(size_t *out, xdfenv_t *xe1, const char *name1,
 				memcpy(dest + size + 1, name3, marker3_size - 1);
 				size += marker3_size;
 			}
+			if (needs_cr)
+				dest[size++] = '\r';
 			dest[size++] = '\n';
 		}
 
-		if (xdl_orig_copy(&copied, xe1, m->i0, m->chg0, 1,
+		if (xdl_orig_copy(&copied, xe1, m->i0, m->chg0, needs_cr, 1,
 				      dest ? dest + size : NULL) < 0)
 			return -1;
 		GITERR_CHECK_ALLOC_ADD(&size, size, copied);
 	}
 
 	if (!dest) {
-		GITERR_CHECK_ALLOC_ADD3(&size, size, marker_size, 1);
+		GITERR_CHECK_ALLOC_ADD4(&size, size, marker_size, 1, needs_cr);
 	} else {
 		memset(dest + size, '=', marker_size);
 		size += marker_size;
+		if (needs_cr)
+			dest[size++] = '\r';
 		dest[size++] = '\n';
 	}
 
 	/* Postimage from side #2 */
 
-	if (xdl_recs_copy(&copied, xe2, m->i2, m->chg2, 1,
+	if (xdl_recs_copy(&copied, xe2, m->i2, m->chg2, needs_cr, 1,
 			      dest ? dest + size : NULL) < 0)
 		return -1;
 	GITERR_CHECK_ALLOC_ADD(&size, size, copied);
 
 	if (!dest) {
-		GITERR_CHECK_ALLOC_ADD4(&size, size, marker_size, 1, marker2_size);
+		GITERR_CHECK_ALLOC_ADD5(&size, size, marker_size, 1, needs_cr, marker2_size);
 	} else {
 		memset(dest + size, '>', marker_size);
 		size += marker_size;
@@ -242,6 +298,8 @@ static int fill_conflict_hunk(size_t *out, xdfenv_t *xe1, const char *name1,
 			memcpy(dest + size + 1, name2, marker2_size - 1);
 			size += marker2_size;
 		}
+		if (needs_cr)
+			dest[size++] = '\r';
 		dest[size++] = '\n';
 	}
 
@@ -275,14 +333,16 @@ static int xdl_fill_merge_buffer(size_t *out,
 		}
 		else if (m->mode & 3) {
 			/* Before conflicting part */
-			if (xdl_recs_copy(&copied, xe1, i, m->i1 - i, 0,
+			if (xdl_recs_copy(&copied, xe1, i, m->i1 - i, 0, 0,
 					      dest ? dest + size : NULL) < 0)
 				return -1;
 			GITERR_CHECK_ALLOC_ADD(&size, size, copied);
 
 			/* Postimage from side #1 */
 			if (m->mode & 1) {
-				if (xdl_recs_copy(&copied, xe1, m->i1, m->chg1, (m->mode & 2),
+				int needs_cr = is_cr_needed(xe1, xe2, m);
+
+				if (xdl_recs_copy(&copied, xe1, m->i1, m->chg1, needs_cr, (m->mode & 2),
 						      dest ? dest + size : NULL) < 0)
 					return -1;
 				GITERR_CHECK_ALLOC_ADD(&size, size, copied);
@@ -290,7 +350,7 @@ static int xdl_fill_merge_buffer(size_t *out,
 
 			/* Postimage from side #2 */
 			if (m->mode & 2) {
-				if (xdl_recs_copy(&copied, xe2, m->i2, m->chg2, 0,
+				if (xdl_recs_copy(&copied, xe2, m->i2, m->chg2, 0, 0,
 						      dest ? dest + size : NULL) < 0)
 					return -1;
 				GITERR_CHECK_ALLOC_ADD(&size, size, copied);
@@ -300,7 +360,7 @@ static int xdl_fill_merge_buffer(size_t *out,
 		i = m->i1 + m->chg1;
 	}
 
-	if (xdl_recs_copy(&copied, xe1, i, xe1->xdf2.nrec - i, 0,
+	if (xdl_recs_copy(&copied, xe1, i, xe1->xdf2.nrec - i, 0, 0,
 			      dest ? dest + size : NULL) < 0)
 		return -1;
 	GITERR_CHECK_ALLOC_ADD(&size, size, copied);
diff --git a/src/xdiff/xpatience.c b/src/xdiff/xpatience.c
index 04e1a1ab2..cedf39cc3 100644
--- a/src/xdiff/xpatience.c
+++ b/src/xdiff/xpatience.c
@@ -1,6 +1,6 @@
 /*
  *  LibXDiff by Davide Libenzi ( File Differential Library )
- *  Copyright (C) 2003-2009 Davide Libenzi, Johannes E. Schindelin
+ *  Copyright (C) 2003-2016 Davide Libenzi, Johannes E. Schindelin
  *
  *  This library is free software; you can redistribute it and/or
  *  modify it under the terms of the GNU Lesser General Public
@@ -13,8 +13,8 @@
  *  Lesser General Public License for more details.
  *
  *  You should have received a copy of the GNU Lesser General Public
- *  License along with this library; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *  License along with this library; if not, see
+ *  <http://www.gnu.org/licenses/>.
  *
  *  Davide Libenzi <davidel@xmailserver.org>
  *
@@ -62,6 +62,12 @@ struct hashmap {
 		 * initially, "next" reflects only the order in file1.
 		 */
 		struct entry *next, *previous;
+
+		/*
+		 * If 1, this entry can serve as an anchor. See
+		 * Documentation/diff-options.txt for more information.
+		 */
+		unsigned anchor : 1;
 	} *entries, *first, *last;
 	/* were common records found? */
 	unsigned long has_matches;
@@ -70,8 +76,19 @@ struct hashmap {
 	xpparam_t const *xpp;
 };
 
+static int is_anchor(xpparam_t const *xpp, const char *line)
+{
+	unsigned long i;
+	for (i = 0; i < xpp->anchors_nr; i++) {
+		if (!strncmp(line, xpp->anchors[i], strlen(xpp->anchors[i])))
+			return 1;
+	}
+	return 0;
+}
+
 /* The argument "pass" is 1 for the first file, 2 for the second. */
-static void insert_record(int line, struct hashmap *map, int pass)
+static void insert_record(xpparam_t const *xpp, int line, struct hashmap *map,
+			  int pass)
 {
 	xrecord_t **records = pass == 1 ?
 		map->env->xdf1.recs : map->env->xdf2.recs;
@@ -110,6 +127,7 @@ static void insert_record(int line, struct hashmap *map, int pass)
 		return;
 	map->entries[index].line1 = line;
 	map->entries[index].hash = record->ha;
+	map->entries[index].anchor = is_anchor(xpp, map->env->xdf1.recs[line - 1]->ptr);
 	if (!map->first)
 		map->first = map->entries + index;
 	if (map->last) {
@@ -147,11 +165,11 @@ static int fill_hashmap(mmfile_t *file1, mmfile_t *file2,
 
 	/* First, fill with entries from the first file */
 	while (count1--)
-		insert_record(line1++, result, 1);
+		insert_record(xpp, line1++, result, 1);
 
 	/* Then search for matches in the second file */
 	while (count2--)
-		insert_record(line2++, result, 2);
+		insert_record(xpp, line2++, result, 2);
 
 	return 0;
 }
@@ -166,7 +184,7 @@ static int binary_search(struct entry **sequence, int longest,
 	int left = -1, right = longest;
 
 	while (left + 1 < right) {
-		int middle = (left + right) / 2;
+		int middle = left + (right - left) / 2;
 		/* by construction, no two entries can be equal */
 		if (sequence[middle]->line2 > entry->line2)
 			right = middle;
@@ -192,14 +210,28 @@ static struct entry *find_longest_common_sequence(struct hashmap *map)
 	int longest = 0, i;
 	struct entry *entry;
 
+	/*
+	 * If not -1, this entry in sequence must never be overridden.
+	 * Therefore, overriding entries before this has no effect, so
+	 * do not do that either.
+	 */
+	int anchor_i = -1;
+
 	for (entry = map->first; entry; entry = entry->next) {
 		if (!entry->line2 || entry->line2 == NON_UNIQUE)
 			continue;
 		i = binary_search(sequence, longest, entry);
 		entry->previous = i < 0 ? NULL : sequence[i];
-		sequence[++i] = entry;
-		if (i == longest)
+		++i;
+		if (i <= anchor_i)
+			continue;
+		sequence[i] = entry;
+		if (entry->anchor) {
+			anchor_i = i;
+			longest = anchor_i + 1;
+		} else if (i == longest) {
 			longest++;
+		}
 	}
 
 	/* No common unique lines were found */
diff --git a/src/xdiff/xprepare.c b/src/xdiff/xprepare.c
index 13b55aba7..abeb8fb84 100644
--- a/src/xdiff/xprepare.c
+++ b/src/xdiff/xprepare.c
@@ -13,8 +13,8 @@
  *  Lesser General Public License for more details.
  *
  *  You should have received a copy of the GNU Lesser General Public
- *  License along with this library; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *  License along with this library; if not, see
+ *  <http://www.gnu.org/licenses/>.
  *
  *  Davide Libenzi <davidel@xmailserver.org>
  *
diff --git a/src/xdiff/xprepare.h b/src/xdiff/xprepare.h
index 8fb06a537..947d9fc1b 100644
--- a/src/xdiff/xprepare.h
+++ b/src/xdiff/xprepare.h
@@ -13,8 +13,8 @@
  *  Lesser General Public License for more details.
  *
  *  You should have received a copy of the GNU Lesser General Public
- *  License along with this library; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *  License along with this library; if not, see
+ *  <http://www.gnu.org/licenses/>.
  *
  *  Davide Libenzi <davidel@xmailserver.org>
  *
diff --git a/src/xdiff/xtypes.h b/src/xdiff/xtypes.h
index 2511aef8d..8442bd436 100644
--- a/src/xdiff/xtypes.h
+++ b/src/xdiff/xtypes.h
@@ -13,8 +13,8 @@
  *  Lesser General Public License for more details.
  *
  *  You should have received a copy of the GNU Lesser General Public
- *  License along with this library; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *  License along with this library; if not, see
+ *  <http://www.gnu.org/licenses/>.
  *
  *  Davide Libenzi <davidel@xmailserver.org>
  *
diff --git a/src/xdiff/xutils.c b/src/xdiff/xutils.c
index 30f2a30ac..17c9ae184 100644
--- a/src/xdiff/xutils.c
+++ b/src/xdiff/xutils.c
@@ -13,8 +13,8 @@
  *  Lesser General Public License for more details.
  *
  *  You should have received a copy of the GNU Lesser General Public
- *  License along with this library; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *  License along with this library; if not, see
+ *  <http://www.gnu.org/licenses/>.
  *
  *  Davide Libenzi <davidel@xmailserver.org>
  *
@@ -62,14 +62,14 @@ int xdl_emit_diffrec(char const *rec, long size, char const *pre, long psize,
 
 void *xdl_mmfile_first(mmfile_t *mmf, long *size)
 {
-	*size = (long)mmf->size;
+	*size = mmf->size;
 	return mmf->ptr;
 }
 
 
 long xdl_mmfile_size(mmfile_t *mmf)
 {
-	return (long)mmf->size;
+	return mmf->size;
 }
 
 
@@ -154,6 +154,24 @@ int xdl_blankline(const char *line, long size, long flags)
 	return (i == size);
 }
 
+/*
+ * Have we eaten everything on the line, except for an optional
+ * CR at the very end?
+ */
+static int ends_with_optional_cr(const char *l, long s, long i)
+{
+	int complete = s && l[s-1] == '\n';
+
+	if (complete)
+		s--;
+	if (s == i)
+		return 1;
+	/* do not ignore CR at the end of an incomplete line */
+	if (complete && s == i + 1 && l[i] == '\r')
+		return 1;
+	return 0;
+}
+
 int xdl_recmatch(const char *l1, long s1, const char *l2, long s2, long flags)
 {
 	int i1, i2;
@@ -168,7 +186,8 @@ int xdl_recmatch(const char *l1, long s1, const char *l2, long s2, long flags)
 
 	/*
 	 * -w matches everything that matches with -b, and -b in turn
-	 * matches everything that matches with --ignore-space-at-eol.
+	 * matches everything that matches with --ignore-space-at-eol,
+	 * which in turn matches everything that matches with --ignore-cr-at-eol.
 	 *
 	 * Each flavor of ignoring needs different logic to skip whitespaces
 	 * while we have both sides to compare.
@@ -198,8 +217,18 @@ int xdl_recmatch(const char *l1, long s1, const char *l2, long s2, long flags)
 				return 0;
 		}
 	} else if (flags & XDF_IGNORE_WHITESPACE_AT_EOL) {
-		while (i1 < s1 && i2 < s2 && l1[i1++] == l2[i2++])
-			; /* keep going */
+		while (i1 < s1 && i2 < s2 && l1[i1] == l2[i2]) {
+			i1++;
+			i2++;
+		}
+	} else if (flags & XDF_IGNORE_CR_AT_EOL) {
+		/* Find the first difference and see how the line ends */
+		while (i1 < s1 && i2 < s2 && l1[i1] == l2[i2]) {
+			i1++;
+			i2++;
+		}
+		return (ends_with_optional_cr(l1, s1, i1) &&
+			ends_with_optional_cr(l2, s2, i2));
 	}
 
 	/*
@@ -226,9 +255,16 @@ static unsigned long xdl_hash_record_with_whitespace(char const **data,
 		char const *top, long flags) {
 	unsigned long ha = 5381;
 	char const *ptr = *data;
+	int cr_at_eol_only = (flags & XDF_WHITESPACE_FLAGS) == XDF_IGNORE_CR_AT_EOL;
 
 	for (; ptr < top && *ptr != '\n'; ptr++) {
-		if (XDL_ISSPACE(*ptr)) {
+		if (cr_at_eol_only) {
+			/* do not ignore CR at the end of an incomplete line */
+			if (*ptr == '\r' &&
+			    (ptr + 1 < top && ptr[1] == '\n'))
+				continue;
+		}
+		else if (XDL_ISSPACE(*ptr)) {
 			const char *ptr2 = ptr;
 			int at_eol;
 			while (ptr + 1 < top && XDL_ISSPACE(ptr[1])
@@ -260,7 +296,6 @@ static unsigned long xdl_hash_record_with_whitespace(char const **data,
 	return ha;
 }
 
-
 unsigned long xdl_hash_record(char const **data, char const *top, long flags) {
 	unsigned long ha = 5381;
 	char const *ptr = *data;
@@ -277,7 +312,6 @@ unsigned long xdl_hash_record(char const **data, char const *top, long flags) {
 	return ha;
 }
 
-
 unsigned int xdl_hashbits(unsigned int size) {
 	unsigned int val = 1, bits = 0;
 
@@ -305,23 +339,9 @@ int xdl_num_out(char *out, long val) {
 		*str++ = '0';
 	*str = '\0';
 
-	return (int)(str - out);
-}
-
-
-long xdl_atol(char const *str, char const **next) {
-	long val, base;
-	char const *top;
-
-	for (top = str; XDL_ISDIGIT(*top); top++);
-	if (next)
-		*next = top;
-	for (val = 0, base = 1, top--; top >= str; top--, base *= 10)
-		val += base * (long)(*top - '0');
-	return val;
+	return str - out;
 }
 
-
 int xdl_emit_hunk_hdr(long s1, long c1, long s2, long c2,
 		      const char *func, long funclen, xdemitcb_t *ecb) {
 	int nb = 0;
@@ -356,8 +376,8 @@ int xdl_emit_hunk_hdr(long s1, long c1, long s2, long c2,
 	nb += 3;
 	if (func && funclen) {
 		buf[nb++] = ' ';
-		if (funclen > (long)sizeof(buf) - nb - 1)
-			funclen = (long)sizeof(buf) - nb - 1;
+		if (funclen > (long)(sizeof(buf) - nb - 1))
+			funclen = sizeof(buf) - nb - 1;
 		memcpy(buf + nb, func, funclen);
 		nb += funclen;
 	}
diff --git a/src/xdiff/xutils.h b/src/xdiff/xutils.h
index 8f952a8e6..fba7bae03 100644
--- a/src/xdiff/xutils.h
+++ b/src/xdiff/xutils.h
@@ -13,8 +13,8 @@
  *  Lesser General Public License for more details.
  *
  *  You should have received a copy of the GNU Lesser General Public
- *  License along with this library; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *  License along with this library; if not, see
+ *  <http://www.gnu.org/licenses/>.
  *
  *  Davide Libenzi <davidel@xmailserver.org>
  *
@@ -31,15 +31,12 @@ int xdl_emit_diffrec(char const *rec, long size, char const *pre, long psize,
 int xdl_cha_init(chastore_t *cha, long isize, long icount);
 void xdl_cha_free(chastore_t *cha);
 void *xdl_cha_alloc(chastore_t *cha);
-void *xdl_cha_first(chastore_t *cha);
-void *xdl_cha_next(chastore_t *cha);
 long xdl_guess_lines(mmfile_t *mf, long sample);
 int xdl_blankline(const char *line, long size, long flags);
 int xdl_recmatch(const char *l1, long s1, const char *l2, long s2, long flags);
 unsigned long xdl_hash_record(char const **data, char const *top, long flags);
 unsigned int xdl_hashbits(unsigned int size);
 int xdl_num_out(char *out, long val);
-long xdl_atol(char const *str, char const **next);
 int xdl_emit_hunk_hdr(long s1, long c1, long s2, long c2,
 		      const char *func, long funclen, xdemitcb_t *ecb);
 int xdl_fall_back_diff(xdfenv_t *diff_env, xpparam_t const *xpp,
diff --git a/tests/merge/files.c b/tests/merge/files.c
index daa73fada..6f5a1fd9c 100644
--- a/tests/merge/files.c
+++ b/tests/merge/files.c
@@ -377,3 +377,51 @@ void test_merge_files__handles_binaries_when_favored(void)
 
 	git_merge_file_result_free(&result);
 }
+
+void test_merge_files__crlf_conflict_markers_for_crlf_files(void)
+{
+	git_merge_file_input ancestor = GIT_MERGE_FILE_INPUT_INIT,
+		ours = GIT_MERGE_FILE_INPUT_INIT,
+		theirs = GIT_MERGE_FILE_INPUT_INIT;
+	git_merge_file_options opts = GIT_MERGE_FILE_OPTIONS_INIT;
+	git_merge_file_result result = {0};
+
+	const char *expected =
+		"<<<<<<< file.txt\r\nThis file\r\ndoes, too.\r\n"
+		"=======\r\nAnd so does\r\nthis one.\r\n>>>>>>> file.txt\r\n";
+	size_t expected_len = strlen(expected);
+
+	const char *expected_diff3 =
+		"<<<<<<< file.txt\r\nThis file\r\ndoes, too.\r\n"
+		"||||||| file.txt\r\nThis file has\r\nCRLF line endings.\r\n"
+		"=======\r\nAnd so does\r\nthis one.\r\n>>>>>>> file.txt\r\n";
+	size_t expected_diff3_len = strlen(expected_diff3);
+
+	ancestor.ptr = "This file has\r\nCRLF line endings.\r\n";
+	ancestor.size = 35;
+	ancestor.path = "file.txt";
+	ancestor.mode = 0100644;
+
+	ours.ptr = "This file\r\ndoes, too.\r\n";
+	ours.size = 23;
+	ours.path = "file.txt";
+	ours.mode = 0100644;
+
+	theirs.ptr = "And so does\r\nthis one.\r\n";
+	theirs.size = 24;
+	theirs.path = "file.txt";
+	theirs.mode = 0100644;
+
+	cl_git_pass(git_merge_file(&result, &ancestor, &ours, &theirs, &opts));
+	cl_assert_equal_i(0, result.automergeable);
+	cl_assert_equal_i(expected_len, result.len);
+	cl_assert(memcmp(expected, result.ptr, expected_len) == 0);
+	git_merge_file_result_free(&result);
+
+	opts.flags |= GIT_MERGE_FILE_STYLE_DIFF3;
+	cl_git_pass(git_merge_file(&result, &ancestor, &ours, &theirs, &opts));
+	cl_assert_equal_i(0, result.automergeable);
+	cl_assert_equal_i(expected_diff3_len, result.len);
+	cl_assert(memcmp(expected_diff3, result.ptr, expected_len) == 0);
+	git_merge_file_result_free(&result);
+}