gout

commit 4bc1c3617eaf670fc84d41e1e14c2edc2cf43d3c
parent da343290aeb35f9e9800f67b311402b7d3487279
Author: Chris Bracken <chris@bracken.jp>
Date:   Wed, 20 May 2026 22:20:11 +0900

writers: default NULL paths to empty string

Calling strcmp() on a NULL string is undefined behaviour.

Diffstat:
M
src/writer/gemini/commit.c
 | 
19
++++++++++---------
M
src/writer/gopher/commit.c
 | 
20
+++++++++++---------
M
src/writer/html/commit.c
 | 
22
+++++++++++-----------

3 files changed, 32 insertions(+), 29 deletions(-)
diff --git a/src/writer/gemini/commit.c b/src/writer/gemini/commit.c
@@ -159,14 +159,14 @@ static void gemini_commit_write_diffstat_row(GeminiCommit* commit,
 
   fprintf(out, "  %c ", delta->status);
   char filename[PATH_MAX];
-  const char* old_file_path = delta->old_file_path;
-  const char* new_file_path = delta->new_file_path;
+  const char* old_path = delta->old_file_path ? delta->old_file_path : "";
+  const char* new_path = delta->new_file_path ? delta->new_file_path : "";
   int r;
-  if (strcmp(old_file_path, new_file_path) == 0) {
-    r = snprintf(filename, sizeof(filename), "%s", old_file_path);
+  if (strcmp(old_path, new_path) == 0) {
+    r = snprintf(filename, sizeof(filename), "%s", old_path);
   } else {
-    r = snprintf(filename, sizeof(filename), "%s -> %s", old_file_path,
-                 new_file_path);
+    r = snprintf(filename, sizeof(filename), "%s -> %s", old_path,
+                 new_path);
   }
   if (r < 0 || (size_t)r >= sizeof(filename)) {
     errx(1, "snprintf: filename truncated or error");
@@ -205,10 +205,11 @@ static void gemini_commit_write_diff_content(GeminiCommit* commit,
 static void gemini_commit_write_diff_delta(GeminiCommit* commit,
                                            const GitDelta* delta) {
   FILE* out = commit->out;
+  const char* old_path = delta->old_file_path ? delta->old_file_path : "";
+  const char* new_path = delta->new_file_path ? delta->new_file_path : "";
   fprintf(out, "=> ../file/");
-  print_percent_encoded(out, delta->new_file_path);
-  fprintf(out, ".gmi diff --git a/%s b/%s\n", delta->old_file_path,
-          delta->new_file_path);
+  print_percent_encoded(out, new_path);
+  fprintf(out, ".gmi diff --git a/%s b/%s\n", old_path, new_path);
 
   if (delta->is_binary) {
     fprintf(out, "Binary files differ.\n\n");
diff --git a/src/writer/gopher/commit.c b/src/writer/gopher/commit.c
@@ -160,14 +160,14 @@ static void gopher_commit_write_diffstat_row(GopherCommit* commit,
 
   fprintf(out, "  %c ", delta->status);
   char filename[PATH_MAX];
-  const char* old_file_path = delta->old_file_path;
-  const char* new_file_path = delta->new_file_path;
+  const char* old_path = delta->old_file_path ? delta->old_file_path : "";
+  const char* new_path = delta->new_file_path ? delta->new_file_path : "";
   int r;
-  if (strcmp(old_file_path, new_file_path) == 0) {
-    r = snprintf(filename, sizeof(filename), "%s", old_file_path);
+  if (strcmp(old_path, new_path) == 0) {
+    r = snprintf(filename, sizeof(filename), "%s", old_path);
   } else {
-    r = snprintf(filename, sizeof(filename), "%s -> %s", old_file_path,
-                 new_file_path);
+    r = snprintf(filename, sizeof(filename), "%s -> %s", old_path,
+                 new_path);
   }
   if (r < 0 || (size_t)r >= sizeof(filename)) {
     errx(1, "snprintf: filename truncated or error");
@@ -207,12 +207,14 @@ static void gopher_commit_write_diff_content(GopherCommit* commit,
 static void gopher_commit_write_diff_delta(GopherCommit* commit,
                                            const GitDelta* delta) {
   FILE* out = commit->out;
+  const char* old_path = delta->old_file_path ? delta->old_file_path : "";
+  const char* new_path = delta->new_file_path ? delta->new_file_path : "";
   fprintf(out, "[1|diff --git a/");
-  print_gopher_link(out, delta->old_file_path);
+  print_gopher_link(out, old_path);
   fprintf(out, " b/");
-  print_gopher_link(out, delta->new_file_path);
+  print_gopher_link(out, new_path);
   fprintf(out, "|../file/");
-  print_gopher_link(out, delta->new_file_path);
+  print_gopher_link(out, new_path);
   fprintf(out, ".gph|server|port]\n");
 
   if (delta->is_binary) {
diff --git a/src/writer/html/commit.c b/src/writer/html/commit.c
@@ -179,12 +179,12 @@ static void html_commit_write_diffstat_row(HtmlCommit* commit,
   fprintf(out, "</td>");
   fprintf(out, "<td>");
   fprintf(out, "<a href=\"#h%zu\">", row);
-  const char* old_file_path = delta->old_file_path;
-  const char* new_file_path = delta->new_file_path;
-  print_xml_encoded(out, old_file_path);
-  if (strcmp(old_file_path, new_file_path) != 0) {
+  const char* old_path = delta->old_file_path ? delta->old_file_path : "";
+  const char* new_path = delta->new_file_path ? delta->new_file_path : "";
+  print_xml_encoded(out, old_path);
+  if (strcmp(old_path, new_path) != 0) {
     fprintf(out, " -&gt; ");
-    print_xml_encoded(out, new_file_path);
+    print_xml_encoded(out, new_path);
   }
   fprintf(out, "</a></td>");
 
@@ -223,17 +223,17 @@ static void html_commit_write_diff_content(HtmlCommit* commit,
 static void html_commit_write_diff_delta(HtmlCommit* commit,
                                          size_t file_num,
                                          const GitDelta* delta) {
-  const char* old_file_path = delta->old_file_path;
-  const char* new_file_path = delta->new_file_path;
+  const char* old_path = delta->old_file_path ? delta->old_file_path : "";
+  const char* new_path = delta->new_file_path ? delta->new_file_path : "";
   fprintf(commit->out, "<b>diff --git ");
   fprintf(commit->out, "a/<a id=\"h%zu\" href=\"../file/", file_num);
-  print_percent_encoded(commit->out, old_file_path);
+  print_percent_encoded(commit->out, old_path);
   fprintf(commit->out, ".html\">");
-  print_xml_encoded(commit->out, old_file_path);
+  print_xml_encoded(commit->out, old_path);
   fprintf(commit->out, "</a> b/<a href=\"../file/");
-  print_percent_encoded(commit->out, new_file_path);
+  print_percent_encoded(commit->out, new_path);
   fprintf(commit->out, ".html\">");
-  print_xml_encoded(commit->out, new_file_path);
+  print_xml_encoded(commit->out, new_path);
   fprintf(commit->out, "</a></b>\n");
 
   if (delta->is_binary) {