all: avoid quoting file names when possible

Quote file names using the "shell-escape" or "shell-escape-always"
methods, which quote as appropriate for most shells,
and better support copy and paste of presented names.
The "always" variant is used when the file name is
embedded in an error message with surrounding spaces.

* cfg.mk (sc_error_shell_quotes): A new syntax check rule
to suggest quotef() where appropriate.
(sc_error_shell_always_quotes): Likewise for quoteaf().
* src/system.h (quotef): A new define to apply shell quoting
when needed.  I.E. when shell character or ':' is present.
(quoteaf): Likewise, but always quote.
* src/*.c: Use quotef() and quoteaf() rather than quote()
where appropriate.
* tests/: Adjust accordingly.

1 files changed, 10 insertions, 10 deletions

diff --git a/src/du.c b/src/du.c
index af6af04f2..19f85a83a 100644
--- a/src/du.c
+++ b/src/du.c
@@ -506,7 +506,7 @@ process_file (FTS *fts, FTSENT *ent)
   if (info == FTS_DNR)
     {
       /* An error occurred, but the size is known, so count it.  */
-      error (0, ent->fts_errno, _("cannot read directory %s"), quote (file));
+      error (0, ent->fts_errno, _("cannot read directory %s"), quoteaf (file));
       ok = false;
     }
   else if (info != FTS_DP)
@@ -526,7 +526,7 @@ process_file (FTS *fts, FTSENT *ent)
 
           if (info == FTS_NS || info == FTS_SLNONE)
             {
-              error (0, ent->fts_errno, _("cannot access %s"), quote (file));
+              error (0, ent->fts_errno, _("cannot access %s"), quoteaf (file));
               return false;
             }
 
@@ -566,7 +566,7 @@ process_file (FTS *fts, FTSENT *ent)
 
         case FTS_ERR:
           /* An error occurred, but the size is known, so count it.  */
-          error (0, ent->fts_errno, "%s", quote (file));
+          error (0, ent->fts_errno, "%s", quotef (file));
           ok = false;
           break;
 
@@ -691,7 +691,7 @@ du_files (char **files, int bit_flags)
               if (errno != 0)
                 {
                   error (0, errno, _("fts_read failed: %s"),
-                         quote (fts->fts_path));
+                         quotef (fts->fts_path));
                   ok = false;
                 }
 
@@ -882,7 +882,7 @@ main (int argc, char **argv)
           if (add_exclude_file (add_exclude, exclude, optarg,
                                 EXCLUDE_WILDCARDS, '\n'))
             {
-              error (0, errno, "%s", quote (optarg));
+              error (0, errno, "%s", quotef (optarg));
               ok = false;
             }
           break;
@@ -1020,7 +1020,7 @@ main (int argc, char **argv)
 
       if (! (STREQ (files_from, "-") || freopen (files_from, "r", stdin)))
         error (EXIT_FAILURE, errno, _("cannot open %s for reading"),
-               quote (files_from));
+               quoteaf (files_from));
 
       ai = argv_iter_init_stream (stdin);
 
@@ -1068,7 +1068,7 @@ main (int argc, char **argv)
               goto argv_iter_done;
             case AI_ERR_READ:
               error (0, errno, _("%s: read error"),
-                     quote (files_from));
+                     quotef (files_from));
               ok = false;
               goto argv_iter_done;
             case AI_ERR_MEM:
@@ -1083,7 +1083,7 @@ main (int argc, char **argv)
              printf - | du --files0-from=- */
           error (0, 0, _("when reading file names from stdin, "
                          "no file name of %s allowed"),
-                 quote (file_name));
+                 quoteaf (file_name));
           skip_file = true;
         }
 
@@ -1105,7 +1105,7 @@ main (int argc, char **argv)
                  not totally appropriate, since NUL is the separator, not NL,
                  but it might be better than nothing.  */
               unsigned long int file_number = argv_iter_n_args (ai);
-              error (0, 0, "%s:%lu: %s", quote (files_from),
+              error (0, 0, "%s:%lu: %s", quotef (files_from),
                      file_number, _("invalid zero-length file name"));
             }
           skip_file = true;
@@ -1127,7 +1127,7 @@ main (int argc, char **argv)
     di_set_free (di_mnt);
 
   if (files_from && (ferror (stdin) || fclose (stdin) != 0) && ok)
-    error (EXIT_FAILURE, 0, _("error reading %s"), quote (files_from));
+    error (EXIT_FAILURE, 0, _("error reading %s"), quoteaf (files_from));
 
   if (print_grand_total)
     print_size (&tot_dui, _("total"));