Rewrite update algorithm.

[chaz/tar] / src / misc.c

diff --git a/src/misc.c b/src/misc.c
index 55bedd2b2c901669ff4025feadbb2fd338984831..cdb2608aa45511cee77721445d4bca2a6e4fa880 100644 (file)
--- a/src/misc.c
+++ b/src/misc.c
@@ -1,11 +1,11 @@
 /* Miscellaneous functions, not really specific to GNU tar.
 
    Copyright (C) 1988, 1992, 1994, 1995, 1996, 1997, 1999, 2000, 2001,
 /* Miscellaneous functions, not really specific to GNU tar.
 
    Copyright (C) 1988, 1992, 1994, 1995, 1996, 1997, 1999, 2000, 2001,

-   2003, 2004, 2005 Free Software Foundation, Inc.
+   2003, 2004, 2005, 2006, 2007, 2009 Free Software Foundation, Inc.

 
    This program is free software; you can redistribute it and/or modify it
    under the terms of the GNU General Public License as published by the
 
    This program is free software; you can redistribute it and/or modify it
    under the terms of the GNU General Public License as published by the

-   Free Software Foundation; either version 2, or (at your option) any later
+   Free Software Foundation; either version 3, or (at your option) any later

    version.
 
    This program is distributed in the hope that it will be useful, but
    version.
 
    This program is distributed in the hope that it will be useful, but


@@ -22,7 +22,17 @@
 #include "common.h"
 #include <quotearg.h>
 #include <save-cwd.h>
 #include "common.h"
 #include <quotearg.h>
 #include <save-cwd.h>

+#include <xgetcwd.h>

 #include <unlinkdir.h>
 #include <unlinkdir.h>

+#include <utimens.h>
+#include <canonicalize.h>
+
+#if HAVE_STROPTS_H
+# include <stropts.h>
+#endif
+#if HAVE_SYS_FILIO_H
+# include <sys/filio.h>
+#endif

 
 \f
 /* Handling strings.  */
 
 \f
 /* Handling strings.  */


@@ -205,6 +215,46 @@ unquote_string (char *string)
     *destination = '\0';
   return result;
 }
     *destination = '\0';
   return result;
 }

+
+/* Zap trailing slashes.  */
+char *
+zap_slashes (char *name)
+{
+  char *q;
+
+  if (!name || *name == 0)
+    return name;
+  q = name + strlen (name) - 1;
+  while (q > name && ISSLASH (*q))
+    *q-- = '\0';
+  return name;
+}
+
+char *
+normalize_filename (const char *name)
+{
+  return zap_slashes (canonicalize_filename_mode (name, CAN_MISSING));
+}
+
+\f
+void
+replace_prefix (char **pname, const char *samp, size_t slen,
+               const char *repl, size_t rlen)
+{
+  char *name = *pname;
+  size_t nlen = strlen (name);
+  if (nlen > slen && memcmp (name, samp, slen) == 0 && ISSLASH (name[slen]))
+    {
+      if (rlen > slen)
+       {
+         name = xrealloc (name, nlen - slen + rlen + 1);
+         *pname = name;
+       }
+      memmove (name + rlen, name + slen, nlen - slen + 1);
+      memcpy (name, repl, rlen);
+    }
+}
+

 \f
 /* Handling numbers.  */
 
 \f
 /* Handling numbers.  */
 


@@ -239,6 +289,27 @@ code_ns_fraction (int ns, char *p)
        }
     }
 }
        }
     }
 }

+
+char const *
+code_timespec (struct timespec t, char sbuf[TIMESPEC_STRSIZE_BOUND])
+{
+  time_t s = t.tv_sec;
+  int ns = t.tv_nsec;
+  char *np;
+  bool negative = s < 0;
+
+  if (negative && ns != 0)
+    {
+      s++;
+      ns = BILLION - ns;
+    }
+
+  np = umaxtostr (negative ? - (uintmax_t) s : (uintmax_t) s, sbuf + 1);
+  if (negative)
+    *--np = '-';
+  code_ns_fraction (ns, sbuf + UINTMAX_STRSIZE_BOUND);
+  return np;
+}

 \f
 /* File handling.  */
 
 \f
 /* File handling.  */
 


@@ -383,10 +454,19 @@ remove_any_file (const char *file_name, enum remove_option option)
    so, we do not have to backup block or character devices, nor remote
    entities.  */
 bool
    so, we do not have to backup block or character devices, nor remote
    entities.  */
 bool

-maybe_backup_file (const char *file_name, int this_is_the_archive)
+maybe_backup_file (const char *file_name, bool this_is_the_archive)

 {
   struct stat file_stat;
 
 {
   struct stat file_stat;
 

+  assign_string (&before_backup_name, file_name);
+
+  /* A run situation may exist between Emacs or other GNU programs trying to
+     make a backup for the same file simultaneously.  If theoretically
+     possible, real problems are unlikely.  Doing any better would require a
+     convention, GNU-wide, for all programs doing backups.  */
+
+  assign_string (&after_backup_name, 0);
+

   /* Check if we really need to backup the file.  */
 
   if (this_is_the_archive && _remdev (file_name))
   /* Check if we really need to backup the file.  */
 
   if (this_is_the_archive && _remdev (file_name))


@@ -408,14 +488,6 @@ maybe_backup_file (const char *file_name, int this_is_the_archive)
       && (S_ISBLK (file_stat.st_mode) || S_ISCHR (file_stat.st_mode)))
     return true;
 
       && (S_ISBLK (file_stat.st_mode) || S_ISCHR (file_stat.st_mode)))
     return true;
 

-  assign_string (&before_backup_name, file_name);
-
-  /* A run situation may exist between Emacs or other GNU programs trying to
-     make a backup for the same file simultaneously.  If theoretically
-     possible, real problems are unlikely.  Doing any better would require a
-     convention, GNU-wide, for all programs doing backups.  */
-
-  assign_string (&after_backup_name, 0);

   after_backup_name = find_backup_file_name (file_name, backup_type);
   if (! after_backup_name)
     xalloc_die ();
   after_backup_name = find_backup_file_name (file_name, backup_type);
   if (! after_backup_name)
     xalloc_die ();


@@ -469,6 +541,26 @@ deref_stat (bool deref, char const *name, struct stat *buf)
   return deref ? stat (name, buf) : lstat (name, buf);
 }
 
   return deref ? stat (name, buf) : lstat (name, buf);
 }
 

+/* Set FD's (i.e., FILE's) access time to TIMESPEC[0].  If that's not
+   possible to do by itself, set its access and data modification
+   times to TIMESPEC[0] and TIMESPEC[1], respectively.  */
+int
+set_file_atime (int fd, char const *file, struct timespec const timespec[2])
+{
+#ifdef _FIOSATIME
+  if (0 <= fd)
+    {
+      struct timeval timeval;
+      timeval.tv_sec = timespec[0].tv_sec;
+      timeval.tv_usec = timespec[0].tv_nsec / 1000;
+      if (ioctl (fd, _FIOSATIME, &timeval) == 0)
+       return 0;
+    }
+#endif
+
+  return gl_futimens (fd, file, timespec);
+}
+

 /* A description of a working directory.  */
 struct wd
 {
 /* A description of a working directory.  */
 struct wd
 {


@@ -481,25 +573,39 @@ struct wd
 static struct wd *wd;
 
 /* The number of working directories in the vector.  */
 static struct wd *wd;
 
 /* The number of working directories in the vector.  */

-static size_t wds;
+static size_t wd_count;

 
 /* The allocated size of the vector.  */
 static size_t wd_alloc;
 
 
 /* The allocated size of the vector.  */
 static size_t wd_alloc;
 

+int
+chdir_count ()
+{
+  if (wd_count == 0)
+    return wd_count;
+  return wd_count - 1;
+}
+

 /* DIR is the operand of a -C option; add it to vector of chdir targets,
    and return the index of its location.  */
 int
 chdir_arg (char const *dir)
 {
 /* DIR is the operand of a -C option; add it to vector of chdir targets,
    and return the index of its location.  */
 int
 chdir_arg (char const *dir)
 {

-  if (wds == wd_alloc)
+  if (wd_count == wd_alloc)

     {
     {

-      wd_alloc = 2 * (wd_alloc + 1);
-      wd = xrealloc (wd, sizeof *wd * wd_alloc);
-      if (! wds)
+      if (wd_alloc == 0)
+       {
+         wd_alloc = 2;
+         wd = xmalloc (sizeof *wd * wd_alloc);
+       }
+      else
+       wd = x2nrealloc (wd, &wd_alloc, sizeof *wd);
+
+      if (! wd_count)

        {
        {

-         wd[wds].name = ".";
-         wd[wds].saved = 0;
-         wds++;
+         wd[wd_count].name = ".";
+         wd[wd_count].saved = 0;
+         wd_count++;

        }
     }
 
        }
     }
 


@@ -511,12 +617,12 @@ chdir_arg (char const *dir)
        for (dir += 2;  ISSLASH (*dir);  dir++)
          continue;
       if (! dir[dir[0] == '.'])
        for (dir += 2;  ISSLASH (*dir);  dir++)
          continue;
       if (! dir[dir[0] == '.'])

-       return wds - 1;
+       return wd_count - 1;

     }
 
     }
 

-  wd[wds].name = dir;
-  wd[wds].saved = 0;
-  return wds++;
+  wd[wd_count].name = dir;
+  wd[wd_count].saved = 0;
+  return wd_count++;

 }
 
 /* Change to directory I.  If I is 0, change to the initial working
 }
 
 /* Change to directory I.  If I is 0, change to the initial working


@@ -533,9 +639,30 @@ chdir_do (int i)
 
       if (! prev->saved)
        {
 
       if (! prev->saved)
        {

+         int err = 0;

          prev->saved = 1;
          if (save_cwd (&prev->saved_cwd) != 0)
          prev->saved = 1;
          if (save_cwd (&prev->saved_cwd) != 0)

-           FATAL_ERROR ((0, 0, _("Cannot save working directory")));
+           err = errno;
+         else if (0 <= prev->saved_cwd.desc)
+           {
+             /* Make sure we still have at least one descriptor available.  */
+             int fd1 = prev->saved_cwd.desc;
+             int fd2 = dup (fd1);
+             if (0 <= fd2)
+               close (fd2);
+             else if (errno == EMFILE)
+               {
+                 /* Force restore_cwd to use chdir_long.  */
+                 close (fd1);
+                 prev->saved_cwd.desc = -1;
+                 prev->saved_cwd.name = xgetcwd ();
+               }
+             else
+               err = errno;
+           }
+
+         if (err)
+           FATAL_ERROR ((0, err, _("Cannot save working directory")));

        }
 
       if (curr->saved)
        }
 
       if (curr->saved)


@@ -618,6 +745,36 @@ stat_diag (char const *name)
     stat_error (name);
 }
 
     stat_error (name);
 }
 

+void
+file_removed_diag (const char *name, bool top_level,
+                  void (*diagfn) (char const *name))
+{
+  if (!top_level && errno == ENOENT)
+    {
+      WARNOPT (WARN_FILE_REMOVED,
+              (0, 0, _("%s: File removed before we read it"),
+               quotearg_colon (name)));
+      set_exit_status (TAREXIT_DIFFERS);
+    }      
+  else
+    diagfn (name);
+}
+
+void
+dir_removed_diag (const char *name, bool top_level,
+                  void (*diagfn) (char const *name))
+{
+  if (!top_level && errno == ENOENT)
+    {
+      WARNOPT (WARN_FILE_REMOVED,
+              (0, 0, _("%s: Directory removed before we read it"),
+               quotearg_colon (name)));
+      set_exit_status (TAREXIT_DIFFERS);
+    }
+  else
+    diagfn (name);
+}
+

 void
 write_fatal_details (char const *name, ssize_t status, size_t size)
 {
 void
 write_fatal_details (char const *name, ssize_t status, size_t size)
 {


@@ -669,3 +826,45 @@ page_aligned_alloc (void **ptr, size_t size)
   *ptr = xmalloc (size1);
   return ptr_align (*ptr, alignment);
 }
   *ptr = xmalloc (size1);
   return ptr_align (*ptr, alignment);
 }

+
+\f
+
+struct namebuf
+{
+  char *buffer;                /* directory, `/', and directory member */
+  size_t buffer_size;  /* allocated size of name_buffer */
+  size_t dir_length;   /* length of directory part in buffer */
+};
+
+namebuf_t
+namebuf_create (const char *dir)
+{
+  namebuf_t buf = xmalloc (sizeof (*buf));
+  buf->buffer_size = strlen (dir) + 2;
+  buf->buffer = xmalloc (buf->buffer_size);
+  strcpy (buf->buffer, dir);
+  buf->dir_length = strlen (buf->buffer);
+  if (!ISSLASH (buf->buffer[buf->dir_length - 1]))
+    buf->buffer[buf->dir_length++] = DIRECTORY_SEPARATOR;
+  return buf;
+}
+
+void
+namebuf_free (namebuf_t buf)
+{
+  free (buf->buffer);
+  free (buf);
+}
+
+char *
+namebuf_name (namebuf_t buf, const char *name)
+{
+  size_t len = strlen (name);
+  while (buf->dir_length + len + 1 >= buf->buffer_size)
+    buf->buffer = x2realloc (buf->buffer, &buf->buffer_size);
+  strcpy (buf->buffer + buf->dir_length, name);
+  return buf->buffer;
+}
+
+
+