fix: mount URL with spaces

src/link.c

@@ -77,10 +77,15 @@ static CURL *Link_to_curl(Link *link)
     if (ret) {
         lprintf(error, "%s", curl_easy_strerror(ret));
     }
-    ret = curl_easy_setopt(curl, CURLOPT_URL, link->f_url);
+
+    char *escaped_spaces = escape_spaces(link->f_url);
+    ret = curl_easy_setopt(curl, CURLOPT_URL,
+                            escaped_spaces ? escaped_spaces : link->f_url);
     if (ret) {
         lprintf(error, "%s", curl_easy_strerror(ret));
     }
+    free(escaped_spaces);
+
     ret = curl_easy_setopt(curl, CURLOPT_TCP_KEEPALIVE, 1);
     if (ret) {
         lprintf(error, "%s", curl_easy_strerror(ret));

src/util.c

@@ -49,6 +49,45 @@ char *path_append(const char *path, const char *filename)
     return str;
 }
 
+char *escape_spaces(const char *path)
+{
+    if (!strchr(path, ' ')) {
+        return NULL;
+    }
+
+    int len = strnlen(path, MAX_PATH_LEN);
+    /* Best case scenario of only one character to escape and
+     * <escaped path array>[MAX_PATH_LEN - 1] is '\0'
+     */
+    if (len + 3 >= MAX_PATH_LEN - 1) {
+        lprintf(fatal, "path too long: %s\n", path);
+    }
+
+    int replacement_len = 3;
+    const char* replacement = "%20";
+
+    char *escaped = CALLOC(MAX_PATH_LEN, sizeof(char));
+
+    int j = 0;
+    for (int i = 0; i < len; i++) {
+        /* Precaution against writing beyond the buffer, since we do not count
+         * all spaces beforehand to know the exact amount of memory to calloc
+         * for the escaped path.
+         */
+        if (j >= MAX_PATH_LEN - 1) {
+            lprintf(fatal, "path too long: %s\n", path);
+        }
+        if (path[i] == ' ') {
+            mempcpy(escaped + j, replacement, replacement_len);
+            j += replacement_len;
+        } else {
+            escaped[j++] = path[i];
+        }
+    }
+    return escaped;
+}
+
+
 int64_t round_div(int64_t a, int64_t b)
 {
     return (a + (b / 2)) / b;

src/util.h

@@ -17,6 +17,14 @@
  */
 char *path_append(const char *path, const char *filename);
 
+/**
+ * \brief escapes the space character in a path/URL
+ * \details This function escapes the space character in a path, and
+ * returns a pointer to the escaped path.
+ * \note You need to free the char * after use.
+ */
+char *escape_spaces(const char *path);
+
 /**
  * \brief division, but rounded to the nearest integer rather than truncating
  */