[PATCH 1/2] xdiff-interface: export comparing and hashing strings

From

Stefan Beller <sbeller@google.com>

Date

Oct 24, 2017, 23:42 UTC

Message-ID

<20171024234234.10944-2-sbeller@google.com>

In-Reply-To

<20171024234234.10944-1-sbeller@google.com>

This will turn out to be useful in a later patch.

While at it, add documentation.

Signed-off-by: Stefan Beller <sbeller@google.com>
---
 xdiff-interface.c | 11 +++++++++++
 xdiff-interface.h | 16 ++++++++++++++++
 2 files changed, 27 insertions(+)

diff --git a/xdiff-interface.c b/xdiff-interface.c
index 018e033089..9b35af2455 100644
--- a/xdiff-interface.c
+++ b/xdiff-interface.c
@@ -5,6 +5,7 @@
 #include "xdiff/xdiffi.h"
 #include "xdiff/xemit.h"
 #include "xdiff/xmacros.h"
+#include "xdiff/xutils.h"
 
 struct xdiff_emit_state {
 	xdiff_emit_consume_fn consume;
@@ -296,6 +297,16 @@ void xdiff_clear_find_func(xdemitconf_t *xecfg)
 	}
 }
 
+unsigned long xdiff_hash_string(const char *s, size_t len, long flags)
+{
+	return xdl_hash_record(&s, s + len, flags);
+}
+
+int xdiff_compare_lines(const char *a, long len_a, const char *b, long len_b, long flags)
+{
+	return xdl_recmatch(a, len_a, b, len_b, flags);
+}
+
 int git_xmerge_style = -1;
 
 int git_xmerge_config(const char *var, const char *value, void *cb)
diff --git a/xdiff-interface.h b/xdiff-interface.h
index 6f6ba9095d..6f5abaf8d3 100644
--- a/xdiff-interface.h
+++ b/xdiff-interface.h
@@ -29,4 +29,20 @@ extern void xdiff_clear_find_func(xdemitconf_t *xecfg);
 extern int git_xmerge_config(const char *var, const char *value, void *cb);
 extern int git_xmerge_style;
 
+/*
+ * Compare the strings l1 with l2 which are of size s1 and s2 respectively.
+ * Returns 1 if the strings are deemed equal, 0 otherwise.
+ * The `flags` given as XDF_WHITESPACE_FLAGS determine how white spaces
+ * are treated for the comparision.
+ */
+extern int xdiff_compare_lines(const char *a, long len_a,
+			       const char *b, long len_b, long flags);
+
+/*
+ * Returns a hash of the string s of length len.
+ * The `flags` given as XDF_WHITESPACE_FLAGS determine how white spaces
+ * are treated for the hash.
+ */
+extern unsigned long xdiff_hash_string(const char *s, size_t len, long flags);
+
 #endif

-- 
2.15.0.rc2.6.g953226eb5f