libc: Copy string views to preallocated buffers

3 files changed, 15 insertions, 3 deletions

diff --git a/userland/httpd/httpd.c b/userland/httpd/httpd.c
index 845355a..aeae6aa 100644
--- a/userland/httpd/httpd.c
+++ b/userland/httpd/httpd.c
@@ -107,9 +107,11 @@ void parse_incoming_request(struct http_request *request) {
     return;
   }
 
-  char *p = SV_TO_C(path);
-  request->file_fd = open(p, O_RDONLY);
-  free(p);
+  {
+    char path_buffer[256];
+    sv_to_cstring_buffer(path, path_buffer, 256);
+    request->file_fd = open(path_buffer, O_RDONLY);
+  }
   if (-1 == request->file_fd) {
     request->status_code = 404;
     return;
diff --git a/userland/libc/include/tb/sv.h b/userland/libc/include/tb/sv.h
index 3d4f9fb..e1ca453 100644
--- a/userland/libc/include/tb/sv.h
+++ b/userland/libc/include/tb/sv.h
@@ -17,6 +17,7 @@ struct sv {
 };
 
 char *SV_TO_C(struct sv s);
+size_t sv_to_cstring_buffer(struct sv s, char *buffer, size_t length);
 struct sv sv_split_delim(const struct sv input, struct sv *rest, char delim);
 struct sv sv_end_split_delim(const struct sv input, struct sv *rest,
                              char delim);
diff --git a/userland/libc/tb/sv.c b/userland/libc/tb/sv.c
index 3f947ef..4ff24fb 100644
--- a/userland/libc/tb/sv.c
+++ b/userland/libc/tb/sv.c
@@ -11,6 +11,15 @@ char *SV_TO_C(struct sv s) {
   return c_string;
 }
 
+size_t sv_to_cstring_buffer(struct sv s, char *buffer, size_t length) {
+  if (0 == length || length - 1 < s.length) {
+    return s.length;
+  }
+  memcpy(buffer, s.s, s.length);
+  buffer[s.length] = '\0';
+  return s.length;
+}
+
 struct sv sv_next(struct sv s) {
   if (0 == s.length) {
     return s;