Merge remote-tracking branch 'public/bug7950' into maint-0.2.4

changes/bug7950

@@ -0,0 +1,4 @@
+  o Minor bugfixes:
+    - When rejecting a configuration because we were unable to parse a
+      quoted string, log an actual error message. Fix for bug 7950;
+      bugfix on 0.2.0.16-alpha.

src/common/util.c

@@ -2428,10 +2428,13 @@ unescape_string(const char *s, char **result, size_t *size_out)
  * key portion and *<b>value_out</b> to a new string holding the value portion
  * of the line, and return a pointer to the start of the next line.  If we run
  * out of data, return a pointer to the end of the string.  If we encounter an
- * error, return NULL.
+ * error, return NULL and set *<b>err_out</b> (if provided) to an error
+ * message.
  */
 const char *
-parse_config_line_from_str(const char *line, char **key_out, char **value_out)
+parse_config_line_from_str_verbose(const char *line, char **key_out,
+                                   char **value_out,
+                                   const char **err_out)
 {
   /* I believe the file format here is supposed to be:
      FILE = (EMPTYLINE | LINE)* (EMPTYLASTLINE | LASTLINE)?
@@ -2505,12 +2508,18 @@ parse_config_line_from_str(const char *line, char **key_out, char **value_out)
 
   /* Find the end of the line. */
   if (*line == '\"') { // XXX No continuation handling is done here
-    if (!(line = unescape_string(line, value_out, NULL)))
-       return NULL;
+    if (!(line = unescape_string(line, value_out, NULL))) {
+      if (err_out)
+        *err_out = "Invalid escape sequence in quoted string";
+      return NULL;
+    }
     while (*line == ' ' || *line == '\t')
       ++line;
-    if (*line && *line != '#' && *line != '\n')
+    if (*line && *line != '#' && *line != '\n') {
+      if (err_out)
+        *err_out = "Excess data after quoted string";
       return NULL;
+    }
   } else {
     /* Look for the end of the line. */
     while (*line && *line != '\n' && (*line != '#' || continuation)) {

src/common/util.h

@@ -369,8 +369,11 @@ char *read_file_to_str(const char *filename, int flags, struct stat *stat_out)
 char *read_file_to_str_until_eof(int fd, size_t max_bytes_to_read,
                                  size_t *sz_out)
   ATTR_MALLOC;
-const char *parse_config_line_from_str(const char *line,
-                                       char **key_out, char **value_out);
+const char *parse_config_line_from_str_verbose(const char *line,
+                                       char **key_out, char **value_out,
+                                       const char **err_out);
+#define parse_config_line_from_str(line,key_out,value_out) \
+  parse_config_line_from_str_verbose((line),(key_out),(value_out),NULL)
 char *expand_filename(const char *filename);
 struct smartlist_t *tor_listdir(const char *dirname);
 int path_is_relative(const char *filename);

src/or/confparse.c

@@ -91,12 +91,15 @@ config_get_lines(const char *string, config_line_t **result, int extended)
 {
   config_line_t *list = NULL, **next;
   char *k, *v;
+  const char *parse_err;
 
   next = &list;
   do {
     k = v = NULL;
-    string = parse_config_line_from_str(string, &k, &v);
+    string = parse_config_line_from_str_verbose(string, &k, &v, &parse_err);
     if (!string) {
+      log_warn(LD_CONFIG, "Error while parsing configuration: %s",
+               parse_err?parse_err:"<unknown>");
       config_free_lines(list);
       tor_free(k);
       tor_free(v);