(main): Stat all non-`-' input file files (and fail if a

stat fails) when an output file is specified by `-o' but doesn't exist.

diff --git a/src/sort.c b/src/sort.c
index a1ada76409af5103de9925583ff475fcf5376c52..5b214281d59969d3ff15aed5e791818e80bb49d4 100644 (file)
--- a/src/sort.c
+++ b/src/sort.c
@@ -2280,7 +2280,9 @@ sort (char **files, int nfiles, FILE *ofp)
 #endif
          sortlines (lines.lines, lines.used, tmp);
          if (feof (fp) && !nfiles && !n_temp_files && !buf.left)
-           tfp = ofp;
+           {
+             tfp = ofp;
+           }
          else
            {
              ++n_temp_files;
@@ -2857,49 +2859,73 @@ but lacks following character offset"));
          for (i = 0; i < nfiles; ++i)
            {
              char buf[8192];
-             FILE *fp;
+             FILE *in_fp;
+             FILE *out_fp;
              int cc;
 
              if (S_ISREG (outstat.st_mode) && !STREQ (outfile, files[i]))
                {
                  struct stat instat;
-                 if ((!STREQ (files[i], "-")
-                      ? stat (files[i], &instat)
-                      : fstat (STDIN_FILENO, &instat)) != 0)
+                 if ((STREQ (files[i], "-")
+                      ? fstat (STDIN_FILENO, &instat)
+                      : stat (files[i], &instat)) != 0)
                    {
                      error (0, errno, "%s", files[i]);
                      cleanup ();
                      exit (SORT_FAILURE);
                    }
-                 if (S_ISREG (instat.st_mode)
-                     && (instat.st_ino != outstat.st_ino
-                         || instat.st_dev != outstat.st_dev))
+                 if (S_ISREG (instat.st_mode) && !SAME_INODE (instat, outstat))
                    {
                      /* We know the files are distinct.  */
                      continue;
                    }
                }
 
-             fp = xfopen (files[i], "r");
+             in_fp = xfopen (files[i], "r");
              tmp = tempname ();
-             ofp = xtmpfopen (tmp);
-             while ((cc = fread (buf, 1, sizeof buf, fp)) > 0)
-               write_bytes (buf, cc, ofp);
-             if (ferror (fp))
+             out_fp = xtmpfopen (tmp);
+             /* FIXME: maybe use copy.c(copy) here. */
+             while ((cc = fread (buf, 1, sizeof buf, in_fp)) > 0)
+               write_bytes (buf, cc, out_fp);
+             if (ferror (in_fp))
                {
                  error (0, errno, "%s", files[i]);
                  cleanup ();
                  exit (SORT_FAILURE);
                }
-             xfclose (ofp);
-             xfclose (fp);
+             xfclose (out_fp);
+             xfclose (in_fp);
              files[i] = tmp;
            }
+         ofp = xfopen (outfile, "w");
+       }
+      else
+       {
+         /* A non-`-' outfile was specified, but the file doesn't yet exist.
+            Before opening it for writing (thus creating it), make sure all
+            of the input files exist.  Otherwise, creating the output file
+            could create an otherwise missing input file, making sort succeed
+            when it should fail.  */
+         for (i = 0; i < nfiles; ++i)
+           {
+             struct stat sb;
+             if (STREQ (files[i], "-"))
+               continue;
+             if (stat (files[i], &sb))
+               {
+                 error (0, errno, "%s", files[i]);
+                 cleanup ();
+                 exit (SORT_FAILURE);
+               }
+           }
+
+         ofp = xfopen (outfile, "w");
        }
-      ofp = xfopen (outfile, "w");
     }
   else
-    ofp = stdout;
+    {
+      ofp = stdout;
+    }
 
   if (mergeonly)
     merge (files, nfiles, ofp);