unexpand: fix incorrect expansion, add test for it

[oweals/busybox.git] / coreutils / dos2unix.c

diff --git a/coreutils/dos2unix.c b/coreutils/dos2unix.c
index 2db7e11a17f7fb9eb375b0a4268d50e01d610f48..309cbc3b819b962e388fd338d513934af9680eb0 100644 (file)
--- a/coreutils/dos2unix.c
+++ b/coreutils/dos2unix.c
@@ -24,24 +24,27 @@ static void convert(char *fn, int conv_type)
 {
        FILE *in, *out;
        int i;
-       char *name_buf = name_buf; /* for compiler */
+       char *temp_fn = temp_fn; /* for compiler */
+       char *resolved_fn = resolved_fn;
 
        in = stdin;
        out = stdout;
        if (fn != NULL) {
-               in = xfopen(fn, "r");
-               /*
-                  The file is then created with mode read/write and
-                  permissions 0666 for glibc 2.0.6 and earlier or
-                  0600 for glibc 2.0.7 and later.
-                */
-               name_buf = xasprintf("%sXXXXXX", fn);
-               i = mkstemp(name_buf);
+               struct stat st;
+
+               resolved_fn = xmalloc_follow_symlinks(fn);
+               if (resolved_fn == NULL)
+                       bb_simple_perror_msg_and_die(fn);
+               in = xfopen_for_read(resolved_fn);
+               fstat(fileno(in), &st);
+
+               temp_fn = xasprintf("%sXXXXXX", resolved_fn);
+               i = mkstemp(temp_fn);
                if (i == -1
-                || fchmod(i, 0600) == -1
+                || fchmod(i, st.st_mode) == -1
                 || !(out = fdopen(i, "w+"))
                ) {
-                       bb_perror_nomsg_and_die();
+                       bb_simple_perror_msg_and_die(temp_fn);
                }
        }
 
@@ -56,12 +59,12 @@ static void convert(char *fn, int conv_type)
 
        if (fn != NULL) {
                if (fclose(in) < 0 || fclose(out) < 0) {
-                       unlink(name_buf);
+                       unlink(temp_fn);
                        bb_perror_nomsg_and_die();
                }
-// TODO: destroys symlinks. See how passwd handles this
-               xrename(name_buf, fn);
-               free(name_buf);
+               xrename(temp_fn, resolved_fn);
+               free(temp_fn);
+               free(resolved_fn);
        }
 }