parse: report errors when failing config parsing

[mirror_lxc.git] / src / lxc / parse.c

diff --git a/src/lxc/parse.c b/src/lxc/parse.c
index 1c0cc9f49127552b4368f1b14a393ee6bdfd1a35..bab842a215f29e0cda524e2f52a827c1c27c7e71 100644 (file)
--- a/src/lxc/parse.c
+++ b/src/lxc/parse.c
@@ -65,34 +65,35 @@ int lxc_strmunmap(void *addr, size_t length)
        return munmap(addr, length + 1);
 }
 
-int lxc_file_for_each_line_mmap(const char *file, lxc_file_cb callback,
-                               void *data)
+int lxc_file_for_each_line_mmap(const char *file, lxc_file_cb callback, void *data)
 {
-       int fd;
+       int fd, saved_errno;
        char *buf, *line;
        struct stat st;
        int ret = 0;
 
        fd = open(file, O_RDONLY | O_CLOEXEC);
-       if (fd < 0)
+       if (fd < 0) {
+               SYSERROR("Failed to open config file \"%s\"", file);
                return -1;
+       }
 
        ret = fstat(fd, &st);
        if (ret < 0) {
-               close(fd);
-               return -1;
+               SYSERROR("Failed to stat config file \"%s\"", file);
+               goto on_error;
        }
 
-       if (st.st_size == 0) {
-               close(fd);
-               return 0;
-       }
+       ret = 0;
+       if (st.st_size == 0)
+               goto on_error;
 
+       ret = -1;
        buf = lxc_strmmap(NULL, st.st_size, PROT_READ | PROT_WRITE,
                          MAP_PRIVATE | MAP_POPULATE, fd, 0);
        if (buf == MAP_FAILED) {
-               close(fd);
-               return -1;
+               SYSERROR("Failed to map config file \"%s\"", file);
+               goto on_error;
        }
 
        lxc_iterate_parts(line, buf, "\n\0") {
@@ -102,13 +103,22 @@ int lxc_file_for_each_line_mmap(const char *file, lxc_file_cb callback,
                         * error.
                         */
                        if (ret < 0)
-                               ERROR("Failed to parse config: %s", line);
+                               ERROR("Failed to parse config file \"%s\" at "
+                                     "line \"%s\"",
+                                     file, line);
                        break;
                }
        }
 
-       lxc_strmunmap(buf, st.st_size);
+on_error:
+       ret = lxc_strmunmap(buf, st.st_size);
+       if (ret < 0)
+               SYSERROR("Failed to unmap config file \"%s\"", file);
+
+       saved_errno = errno;
        close(fd);
+       errno = saved_errno;
+
        return ret;
 }