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
@@ -241,24 +241,26 @@ static void querystring_cb(const char *name, const char *value)
 	} else if (!strcmp(name, "name")) {
 		ctx.qry.name = xstrdup(value);
 	} else if (!strcmp(name, "mimetype")) {
 		ctx.qry.mimetype = xstrdup(value);
 	} else if (!strcmp(name, "s")){
 		ctx.qry.sort = xstrdup(value);
 	} else if (!strcmp(name, "showmsg")) {
 		ctx.qry.showmsg = atoi(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)
 {
 	return (str ? xstrdup(str) : NULL);
 }
 
 static void prepare_context(struct cgit_context *ctx)
 {
 	memset(ctx, 0, sizeof(*ctx));
 	ctx->cfg.agefile = "info/web/last-modified";
diff --git a/cgit.h b/cgit.h
index f990b15..bb8f598 100644
--- a/cgit.h
+++ b/cgit.h
@@ -136,24 +136,25 @@ struct cgit_query {
 	char *sha1;
 	char *sha2;
 	char *path;
 	char *name;
 	char *mimetype;
 	char *url;
 	char *period;
 	int   ofs;
 	int nohead;
 	char *sort;
 	int showmsg;
 	int ssdiff;
+	int context;
 	char *vpath;
 };
 
 struct cgit_config {
 	char *agefile;
 	char *cache_root;
 	char *clone_prefix;
 	char *css;
 	char *favicon;
 	char *footer;
 	char *head_include;
 	char *header;
@@ -265,25 +266,25 @@ extern char *trim_end(const char *str, char c);
 extern char *strlpart(char *txt, int maxlen);
 extern char *strrpart(char *txt, int maxlen);
 
 extern void cgit_add_ref(struct reflist *list, struct refinfo *ref);
 extern int cgit_refs_cb(const char *refname, const unsigned char *sha1,
 			int flags, void *cb_data);
 
 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);
 
 extern void cgit_diff_commit(struct commit *commit, filepair_fn fn);
 
 extern char *fmt(const char *format,...);
 
 extern struct commitinfo *cgit_parse_commit(struct commit *commit);
 extern struct taginfo *cgit_parse_tag(struct tag *tag);
 extern void cgit_parse_url(const char *url);
diff --git a/shared.c b/shared.c
index 6e8f0ce..7cf1e59 100644
--- a/shared.c
+++ b/shared.c
@@ -253,48 +253,49 @@ int filediff_cb(void *priv, mmbuffer_t *mb, int nbuf)
 	}
 	if (diffbuf) {
 		((linediff_fn)priv)(diffbuf, buflen);
 		free(diffbuf);
 		diffbuf = NULL;
 		buflen = 0;
 	}
 	return 0;
 }
 
 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;
 	xdemitcb_t emit_cb;
 
 	if (!load_mmfile(&file1, old_sha1) || !load_mmfile(&file2, new_sha1))
 		return 1;
 
 	*old_size = file1.size;
 	*new_size = file2.size;
 
 	if ((file1.ptr && buffer_is_binary(file1.ptr, file1.size)) ||
 	    (file2.ptr && buffer_is_binary(file2.ptr, file2.size))) {
 		*binary = 1;
 		return 0;
 	}
 
 	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);
 	return 0;
 }
 
 void cgit_diff_tree(const unsigned char *old_sha1,
 		    const unsigned char *new_sha1,
 		    filepair_fn fn, const char *prefix)
 {
 	struct diff_options opt;
diff --git a/ui-diff.c b/ui-diff.c
index fb836df..d3a3b2c 100644
--- a/ui-diff.c
+++ b/ui-diff.c
@@ -118,25 +118,25 @@ static void count_diff_lines(char *line, int len)
 	}
 }
 
 static void inspect_filepair(struct diff_filepair *pair)
 {
 	int binary = 0;
 	unsigned long old_size = 0;
 	unsigned long new_size = 0;
 	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
 			slots = slots * 2;
 		items = xrealloc(items, slots * sizeof(struct fileinfo));
 	}
 	items[files-1].status = pair->status;
 	hashcpy(items[files-1].old_sha1, pair->one->sha1);
 	hashcpy(items[files-1].new_sha1, pair->two->sha1);
 	items[files-1].old_mode = pair->one->mode;
 	items[files-1].new_mode = pair->two->mode;
@@ -279,25 +279,25 @@ static void filepair_cb(struct diff_filepair *pair)
 	if (use_ssdiff)
 		cgit_ssdiff_header_end();
 	if (S_ISGITLINK(pair->one->mode) || S_ISGITLINK(pair->two->mode)) {
 		if (S_ISGITLINK(pair->one->mode))
 			print_line_fn(fmt("-Subproject %s", sha1_to_hex(pair->one->sha1)), 52);
 		if (S_ISGITLINK(pair->two->mode))
 			print_line_fn(fmt("+Subproject %s", sha1_to_hex(pair->two->sha1)), 52);
 		if (use_ssdiff)
 			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>");
 		else
 			html("Binary files differ");
 	}
 	if (use_ssdiff)
 		cgit_ssdiff_footer();
 }
 
 void cgit_print_diff(const char *new_rev, const char *old_rev, const char *prefix)
diff --git a/ui-log.c b/ui-log.c
index bfbe436..5eb5c81 100644
--- a/ui-log.c
+++ b/ui-log.c
@@ -24,25 +24,25 @@ void count_lines(char *line, int size)
 		rem_lines++;
 }
 
 void inspect_files(struct diff_filepair *pair)
 {
 	unsigned long old_size = 0;
 	unsigned long new_size = 0;
 	int binary = 0;
 
 	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)
 {
 	struct name_decoration *deco;
 	static char buf[1024];
 
 	buf[sizeof(buf) - 1] = 0;
 	deco = lookup_decoration(&name_decoration, &commit->object);
 	while (deco) {
 		if (!prefixcmp(deco->name, "refs/heads/")) {
 			strncpy(buf, deco->name + 11, sizeof(buf) - 1);
diff --git a/ui-patch.c b/ui-patch.c
index 25dc9fe..d13104c 100644
--- a/ui-patch.c
+++ b/ui-patch.c
@@ -62,25 +62,25 @@ static void filepair_cb(struct diff_filepair *pair)
 	int binary = 0;
 
 	header(pair->one->sha1, pair->one->path, pair->one->mode,
 	       pair->two->sha1, pair->two->path, pair->two->mode);
 	if (S_ISGITLINK(pair->one->mode) || S_ISGITLINK(pair->two->mode)) {
 		if (S_ISGITLINK(pair->one->mode))
 			print_line(fmt("-Subproject %s", sha1_to_hex(pair->one->sha1)), 52);
 		if (S_ISGITLINK(pair->two->mode))
 			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");
 }
 
 void cgit_print_patch(char *hex, const char *prefix)
 {
 	struct commit *commit;
 	struct commitinfo *info;
 	unsigned char sha1[20], old_sha1[20];
 	char *patchname;