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
@@ -247,12 +247,14 @@ static void querystring_cb(const char *name, const char *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);
diff --git a/cgit.h b/cgit.h
index f990b15..bb8f598 100644
--- a/cgit.h
+++ b/cgit.h
@@ -142,12 +142,13 @@ struct cgit_query {
         char *period;
         int   ofs;
         int nohead;
         char *sort;
         int showmsg;
         int ssdiff;
+        int context;
         char *vpath;
 };
 
 struct cgit_config {
         char *agefile;
         char *cache_root;
@@ -271,13 +272,13 @@ extern int cgit_refs_cb(const char *refname, const unsigned char *sha1,
 
 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);
diff --git a/shared.c b/shared.c
index 6e8f0ce..7cf1e59 100644
--- a/shared.c
+++ b/shared.c
@@ -259,13 +259,14 @@ int filediff_cb(void *priv, mmbuffer_t *mb, int nbuf)
         }
         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;
 
@@ -282,13 +283,13 @@ 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);
         return 0;
 }
diff --git a/ui-diff.c b/ui-diff.c
index fb836df..d3a3b2c 100644
--- a/ui-diff.c
+++ b/ui-diff.c
@@ -124,13 +124,13 @@ static void inspect_filepair(struct diff_filepair *pair)
         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));
@@ -285,13 +285,13 @@ static void filepair_cb(struct diff_filepair *pair)
                         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");
diff --git a/ui-log.c b/ui-log.c
index bfbe436..5eb5c81 100644
--- a/ui-log.c
+++ b/ui-log.c
@@ -30,13 +30,13 @@ void inspect_files(struct diff_filepair *pair)
         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];
diff --git a/ui-patch.c b/ui-patch.c
index 25dc9fe..d13104c 100644
--- a/ui-patch.c
+++ b/ui-patch.c
@@ -68,13 +68,13 @@ static void filepair_cb(struct diff_filepair *pair)
                         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)