(copy_files): Accept backup options just as cp, ln, and

mv do: --backup (-b).  From Marty Leisner <leisner@sdsp.mc.xerox.c>.

diff --git a/src/install.c b/src/install.c
index 1e32ef4cdb400a751f444cdd23ca78a4494561fe..08cc9265f00c0cd49b00657b6f8b57a8f7eb9b36 100644 (file)
--- a/src/install.c
+++ b/src/install.c
@@ -61,6 +61,7 @@
 
 #include "system.h"
 #include "version.h"
+#include "backupfile.h"
 #include "modechange.h"
 #include "makepath.h"
 #include "error.h"
@@ -98,6 +99,7 @@ char *xmalloc ();
 int safe_read ();
 int full_write ();
 int isdir ();
+enum backup_type get_version ();
 
 static int change_attributes __P ((char *path, int no_need_to_chown));
 static int copy_file __P ((char *from, char *to, int *to_created));
@@ -147,6 +149,8 @@ static struct option const long_options[] =
   {"group", required_argument, NULL, 'g'},
   {"mode", required_argument, NULL, 'm'},
   {"owner", required_argument, NULL, 'o'},
+  {"backup", no_argument, NULL, 'b'},
+  {"version-control", required_argument, NULL, 'V'},
   {"help", no_argument, &show_help, 1},
   {"version", no_argument, &show_version, 1},
   {NULL, 0, NULL, 0}
@@ -158,6 +162,8 @@ main (int argc, char **argv)
   int optc;
   int errors = 0;
   char *symbolic_mode = NULL;
+  int make_backups = 0;
+  char *version;
 
   program_name = argv[0];
   owner_name = NULL;
@@ -167,13 +173,21 @@ main (int argc, char **argv)
   dir_arg = 0;
   umask (0);
 
-  while ((optc = getopt_long (argc, argv, "csdg:m:o:", long_options,
+   version = getenv ("SIMPLE_BACKUP_SUFFIX");
+   if (version)
+      simple_backup_suffix = version;
+   version = getenv ("VERSION_CONTROL");
+
+  while ((optc = getopt_long (argc, argv, "bcsdg:m:o:V:S:", long_options,
                              (int *) 0)) != EOF)
     {
       switch (optc)
        {
        case 0:
          break;
+       case 'b':
+         make_backups = 1;
+         break;
        case 'c':
          break;
        case 's':
@@ -191,6 +205,9 @@ main (int argc, char **argv)
        case 'o':
          owner_name = optarg;
          break;
+        case 'V':
+         version = optarg;
+         break;
        default:
          usage (1);
        }
@@ -210,6 +227,9 @@ main (int argc, char **argv)
     error (1, 0,
           _("the strip option may not be used when installing a directory"));
 
+  if (make_backups)
+    backup_type = get_version (version);
+
   if (optind == argc || (optind == argc - 1 && !dir_arg))
     {
       error (0, 0, _("too few arguments"));
@@ -339,6 +359,28 @@ copy_file (char *from, char *to, int *to_created)
          error (0, 0, _("`%s' and `%s' are the same file"), from, to);
          return 1;
        }
+
+      /* The destination file exists.  Try to back it up if required.  */
+      if (backup_type != none)
+        {
+         char *tmp_backup = find_backup_file_name (to);
+         char *dst_backup;
+
+         if (tmp_backup == NULL)
+           error (1, 0, "virtual memory exhausted");
+         dst_backup = (char *) alloca (strlen (tmp_backup) + 1);
+         strcpy (dst_backup, tmp_backup);
+         free (tmp_backup);
+         if (rename (to, dst_backup))
+           {
+             if (errno != ENOENT)
+               {
+                 error (0, errno, "cannot backup `%s'", to);
+                 return 1;
+               }
+           }
+       }
+
       /* If unlink fails, try to proceed anyway.  */
       if (unlink (to))
        target_created = 0;
@@ -546,6 +588,9 @@ format, make all components of the given DIRECTORY(ies).\n\
   -m, --mode=MODE     set permission mode (as in chmod), instead of rw-r--r--\n\
   -o, --owner=OWNER   set ownership (super-user only)\n\
   -s, --strip         strip symbol tables, only for 1st and 2nd formats\n\
+  -b, --backup        make backup before removal\n\
+  -S, --suffix=SUFFIX override the usual backup suffix\n\
+  -V, --version-control=WORD   override the usual version control\n\
       --help          display this help and exit\n\
       --version       output version information and exit\n"));
     }