Add URL parameter 'context' for changing the number of context lines in diffs

The new ctx.qry.context variable is picked up by cgit_print_diff(), and
passed via cgit_diff_files() to Git's diff machinery.

Signed-off-by: Johan Herland <johan@herland.net>
Signed-off-by: Lars Hjemli <hjemli@gmail.com>

6 files changed, 11 insertions, 7 deletions

diff --git a/cgit.c b/cgit.c
index 2c3ad73..e9bafb5 100644
--- a/cgit.c
+++ b/cgit.c
@@ -249,8 +249,10 @@ static void querystring_cb(const char *name, const char *value)
 	} else if (!strcmp(name, "period")) {
 		ctx.qry.period = xstrdup(value);
 	} else if (!strcmp(name, "ss")) {
 		ctx.qry.ssdiff = atoi(value);
+	} else if (!strcmp(name, "context")) {
+		ctx.qry.context = atoi(value);
 	}
 }
 
 char *xstrdupn(const char *str)
diff --git a/cgit.h b/cgit.h
index f990b15..bb8f598 100644
--- a/cgit.h
+++ b/cgit.h
@@ -144,8 +144,9 @@ struct cgit_query {
 	int nohead;
 	char *sort;
 	int showmsg;
 	int ssdiff;
+	int context;
 	char *vpath;
 };
 
 struct cgit_config {
@@ -273,9 +274,9 @@ extern void *cgit_free_commitinfo(struct commitinfo *info);
 
 extern int cgit_diff_files(const unsigned char *old_sha1,
 			   const unsigned char *new_sha1,
 			   unsigned long *old_size, unsigned long *new_size,
-			   int *binary, linediff_fn fn);
+			   int *binary, int context, linediff_fn fn);
 
 extern void cgit_diff_tree(const unsigned char *old_sha1,
 			   const unsigned char *new_sha1,
 			   filepair_fn fn, const char *prefix);
diff --git a/shared.c b/shared.c
index 6e8f0ce..7cf1e59 100644
--- a/shared.c
+++ b/shared.c
@@ -261,9 +261,10 @@ int filediff_cb(void *priv, mmbuffer_t *mb, int nbuf)
 }
 
 int cgit_diff_files(const unsigned char *old_sha1,
 		    const unsigned char *new_sha1, unsigned long *old_size,
-		    unsigned long *new_size, int *binary, linediff_fn fn)
+		    unsigned long *new_size, int *binary, int context,
+		    linediff_fn fn)
 {
 	mmfile_t file1, file2;
 	xpparam_t diff_params;
 	xdemitconf_t emit_params;
@@ -284,9 +285,9 @@ int cgit_diff_files(const unsigned char *old_sha1,
 	memset(&diff_params, 0, sizeof(diff_params));
 	memset(&emit_params, 0, sizeof(emit_params));
 	memset(&emit_cb, 0, sizeof(emit_cb));
 	diff_params.flags = XDF_NEED_MINIMAL;
-	emit_params.ctxlen = 3;
+	emit_params.ctxlen = context > 0 ? context : 3;
 	emit_params.flags = XDL_EMIT_FUNCNAMES;
 	emit_cb.outf = filediff_cb;
 	emit_cb.priv = fn;
 	xdl_diff(&file1, &file2, &diff_params, &emit_params, &emit_cb);
diff --git a/ui-diff.c b/ui-diff.c
index fb836df..d3a3b2c 100644
--- a/ui-diff.c
+++ b/ui-diff.c
@@ -126,9 +126,9 @@ static void inspect_filepair(struct diff_filepair *pair)
 	files++;
 	lines_added = 0;
 	lines_removed = 0;
 	cgit_diff_files(pair->one->sha1, pair->two->sha1, &old_size, &new_size,
-			&binary, count_diff_lines);
+			&binary, 0, count_diff_lines);
 	if (files >= slots) {
 		if (slots == 0)
 			slots = 4;
 		else
@@ -287,9 +287,9 @@ static void filepair_cb(struct diff_filepair *pair)
 			cgit_ssdiff_footer();
 		return;
 	}
 	if (cgit_diff_files(pair->one->sha1, pair->two->sha1, &old_size,
-			    &new_size, &binary, print_line_fn))
+			    &new_size, &binary, ctx.qry.context, print_line_fn))
 		cgit_print_error("Error running diff");
 	if (binary) {
 		if (use_ssdiff)
 			html("<tr><td colspan='4'>Binary files differ</td></tr>");
diff --git a/ui-log.c b/ui-log.c
index bfbe436..5eb5c81 100644
--- a/ui-log.c
+++ b/ui-log.c
@@ -32,9 +32,9 @@ void inspect_files(struct diff_filepair *pair)
 
 	files++;
 	if (ctx.repo->enable_log_linecount)
 		cgit_diff_files(pair->one->sha1, pair->two->sha1, &old_size,
-				&new_size, &binary, count_lines);
+				&new_size, &binary, 0, count_lines);
 }
 
 void show_commit_decorations(struct commit *commit)
 {
diff --git a/ui-patch.c b/ui-patch.c
index 25dc9fe..d13104c 100644
--- a/ui-patch.c
+++ b/ui-patch.c
@@ -70,9 +70,9 @@ static void filepair_cb(struct diff_filepair *pair)
 			print_line(fmt("+Subproject %s", sha1_to_hex(pair->two->sha1)), 52);
 		return;
 	}
 	if (cgit_diff_files(pair->one->sha1, pair->two->sha1, &old_size,
-			    &new_size, &binary, print_line))
+			    &new_size, &binary, 0, print_line))
 		html("Error running diff");
 	if (binary)
 		html("Binary files differ\n");
 }