1 files changed, 123 insertions, 0 deletions
diff --git a/xdiff-interface.c b/xdiff-interface.c
new file mode 100644
index 0000000000..6c1f99b149
--- /dev/null
+++ b/xdiff-interface.c
@@ -0,0 +1,123 @@
+#include "cache.h"
+#include "xdiff-interface.h"
+
+static int parse_num(char **cp_p, int *num_p)
+{
+	char *cp = *cp_p;
+	int num = 0;
+	int read_some;
+
+	while ('0' <= *cp && *cp <= '9')
+		num = num * 10 + *cp++ - '0';
+	if (!(read_some = cp - *cp_p))
+		return -1;
+	*cp_p = cp;
+	*num_p = num;
+	return 0;
+}
+
+int parse_hunk_header(char *line, int len,
+		      int *ob, int *on,
+		      int *nb, int *nn)
+{
+	char *cp;
+	cp = line + 4;
+	if (parse_num(&cp, ob)) {
+	bad_line:
+		return error("malformed diff output: %s", line);
+	}
+	if (*cp == ',') {
+		cp++;
+		if (parse_num(&cp, on))
+			goto bad_line;
+	}
+	else
+		*on = 1;
+	if (*cp++ != ' ' || *cp++ != '+')
+		goto bad_line;
+	if (parse_num(&cp, nb))
+		goto bad_line;
+	if (*cp == ',') {
+		cp++;
+		if (parse_num(&cp, nn))
+			goto bad_line;
+	}
+	else
+		*nn = 1;
+	return -!!memcmp(cp, " @@", 3);
+}
+
+static void consume_one(void *priv_, char *s, unsigned long size)
+{
+	struct xdiff_emit_state *priv = priv_;
+	char *ep;
+	while (size) {
+		unsigned long this_size;
+		ep = memchr(s, '\n', size);
+		this_size = (ep == NULL) ? size : (ep - s + 1);
+		priv->consume(priv, s, this_size);
+		size -= this_size;
+		s += this_size;
+	}
+}
+
+int xdiff_outf(void *priv_, mmbuffer_t *mb, int nbuf)
+{
+	struct xdiff_emit_state *priv = priv_;
+	int i;
+
+	for (i = 0; i < nbuf; i++) {
+		if (mb[i].ptr[mb[i].size-1] != '\n') {
+			/* Incomplete line */
+			priv->remainder = xrealloc(priv->remainder,
+						   priv->remainder_size +
+						   mb[i].size);
+			memcpy(priv->remainder + priv->remainder_size,
+			       mb[i].ptr, mb[i].size);
+			priv->remainder_size += mb[i].size;
+			continue;
+		}
+
+		/* we have a complete line */
+		if (!priv->remainder) {
+			consume_one(priv, mb[i].ptr, mb[i].size);
+			continue;
+		}
+		priv->remainder = xrealloc(priv->remainder,
+					   priv->remainder_size +
+					   mb[i].size);
+		memcpy(priv->remainder + priv->remainder_size,
+		       mb[i].ptr, mb[i].size);
+		consume_one(priv, priv->remainder,
+			    priv->remainder_size + mb[i].size);
+		free(priv->remainder);
+		priv->remainder = NULL;
+		priv->remainder_size = 0;
+	}
+	if (priv->remainder) {
+		consume_one(priv, priv->remainder, priv->remainder_size);
+		free(priv->remainder);
+		priv->remainder = NULL;
+		priv->remainder_size = 0;
+	}
+	return 0;
+}
+
+int read_mmfile(mmfile_t *ptr, const char *filename)
+{
+	struct stat st;
+	FILE *f;
+
+	if (stat(filename, &st))
+		return error("Could not stat %s", filename);
+	if ((f = fopen(filename, "rb")) == NULL)
+		return error("Could not open %s", filename);
+	ptr->ptr = xmalloc(st.st_size);
+	if (fread(ptr->ptr, st.st_size, 1, f) != 1)
+		return error("Could not read %s", filename);
+	fclose(f);
+	ptr->size = st.st_size;
+	return 0;
+}
+
+