diffutils-3.5HEADdiffutils-3.5master

1 files changed, 385 insertions, 0 deletions

diff --git a/src/dir.c b/src/dir.c
new file mode 100644
index 0000000..c8aa6a5
--- /dev/null
+++ b/src/dir.c
@@ -0,0 +1,385 @@
+/* Read, sort and compare two directories.  Used for GNU DIFF.
+
+   Copyright (C) 1988-1989, 1992-1995, 1998, 2001-2002, 2004, 2006-2007,
+   2009-2013, 2015-2016 Free Software Foundation, Inc.
+
+   This file is part of GNU DIFF.
+
+   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 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include "diff.h"
+#include <error.h>
+#include <exclude.h>
+#include <filenamecat.h>
+#include <setjmp.h>
+#include <xalloc.h>
+
+/* Read the directory named by DIR and store into DIRDATA a sorted vector
+   of filenames for its contents.  DIR->desc == -1 means this directory is
+   known to be nonexistent, so set DIRDATA to an empty vector.
+   Return -1 (setting errno) if error, 0 otherwise.  */
+
+struct dirdata
+{
+  size_t nnames;	/* Number of names.  */
+  char const **names;	/* Sorted names of files in dir, followed by 0.  */
+  char *data;	/* Allocated storage for file names.  */
+};
+
+/* Whether file names in directories should be compared with
+   locale-specific sorting.  */
+static bool locale_specific_sorting;
+
+/* Where to go if locale-specific sorting fails.  */
+static jmp_buf failed_locale_specific_sorting;
+
+static bool dir_loop (struct comparison const *, int);
+
+
+/* Read a directory and get its vector of names.  */
+
+static bool
+dir_read (struct file_data const *dir, struct dirdata *dirdata)
+{
+  register struct dirent *next;
+  register size_t i;
+
+  /* Address of block containing the files that are described.  */
+  char const **names;
+
+  /* Number of files in directory.  */
+  size_t nnames;
+
+  /* Allocated and used storage for file name data.  */
+  char *data;
+  size_t data_alloc, data_used;
+
+  dirdata->names = 0;
+  dirdata->data = 0;
+  nnames = 0;
+  data = 0;
+
+  if (dir->desc != -1)
+    {
+      /* Open the directory and check for errors.  */
+      register DIR *reading = opendir (dir->name);
+      if (!reading)
+	return false;
+
+      /* Initialize the table of filenames.  */
+
+      data_alloc = 512;
+      data_used = 0;
+      dirdata->data = data = xmalloc (data_alloc);
+
+      /* Read the directory entries, and insert the subfiles
+	 into the 'data' table.  */
+
+      while ((errno = 0, (next = readdir (reading)) != 0))
+	{
+	  char *d_name = next->d_name;
+	  size_t d_size = _D_EXACT_NAMLEN (next) + 1;
+
+	  /* Ignore "." and "..".  */
+	  if (d_name[0] == '.'
+	      && (d_name[1] == 0 || (d_name[1] == '.' && d_name[2] == 0)))
+	    continue;
+
+	  if (excluded_file_name (excluded, d_name))
+	    continue;
+
+	  while (data_alloc < data_used + d_size)
+	    {
+	      if (PTRDIFF_MAX / 2 <= data_alloc)
+		xalloc_die ();
+	      dirdata->data = data = xrealloc (data, data_alloc *= 2);
+	    }
+
+	  memcpy (data + data_used, d_name, d_size);
+	  data_used += d_size;
+	  nnames++;
+	}
+      if (errno)
+	{
+	  int e = errno;
+	  closedir (reading);
+	  errno = e;
+	  return false;
+	}
+#if CLOSEDIR_VOID
+      closedir (reading);
+#else
+      if (closedir (reading) != 0)
+	return false;
+#endif
+    }
+
+  /* Create the 'names' table from the 'data' table.  */
+  if (PTRDIFF_MAX / sizeof *names - 1 <= nnames)
+    xalloc_die ();
+  dirdata->names = names = xmalloc ((nnames + 1) * sizeof *names);
+  dirdata->nnames = nnames;
+  for (i = 0;  i < nnames;  i++)
+    {
+      names[i] = data;
+      data += strlen (data) + 1;
+    }
+  names[nnames] = 0;
+  return true;
+}
+
+/* Compare strings in a locale-specific way, returning a value
+   compatible with strcmp.  */
+
+static int
+compare_collated (char const *name1, char const *name2)
+{
+  int r;
+  errno = 0;
+  if (ignore_file_name_case)
+    r = strcasecoll (name1, name2);
+  else
+    r = strcoll (name1, name2);
+  if (errno)
+    {
+      error (0, errno, _("cannot compare file names '%s' and '%s'"),
+	     name1, name2);
+      longjmp (failed_locale_specific_sorting, 1);
+    }
+  return r;
+}
+
+/* Compare file names, returning a value compatible with strcmp.  */
+
+static int
+compare_names (char const *name1, char const *name2)
+{
+  if (locale_specific_sorting)
+    {
+      int diff = compare_collated (name1, name2);
+      if (diff || ignore_file_name_case)
+	return diff;
+    }
+  return file_name_cmp (name1, name2);
+}
+
+/* Compare names FILE1 and FILE2 when sorting a directory.
+   Prefer filtered comparison, breaking ties with file_name_cmp.  */
+
+static int
+compare_names_for_qsort (void const *file1, void const *file2)
+{
+  char const *const *f1 = file1;
+  char const *const *f2 = file2;
+  char const *name1 = *f1;
+  char const *name2 = *f2;
+  if (locale_specific_sorting)
+    {
+      int diff = compare_collated (name1, name2);
+      if (diff)
+	return diff;
+    }
+  return file_name_cmp (name1, name2);
+}
+
+/* Compare the contents of two directories named in CMP.
+   This is a top-level routine; it does everything necessary for diff
+   on two directories.
+
+   CMP->file[0].desc == -1 says directory CMP->file[0] doesn't exist,
+   but pretend it is empty.  Likewise for CMP->file[1].
+
+   HANDLE_FILE is a caller-provided subroutine called to handle each file.
+   It gets three operands: CMP, name of file in dir 0, name of file in dir 1.
+   These names are relative to the original working directory.
+
+   For a file that appears in only one of the dirs, one of the name-args
+   to HANDLE_FILE is zero.
+
+   Returns the maximum of all the values returned by HANDLE_FILE,
+   or EXIT_TROUBLE if trouble is encountered in opening files.  */
+
+int
+diff_dirs (struct comparison const *cmp,
+	   int (*handle_file) (struct comparison const *,
+			       char const *, char const *))
+{
+  struct dirdata dirdata[2];
+  int volatile val = EXIT_SUCCESS;
+  int i;
+
+  if ((cmp->file[0].desc == -1 || dir_loop (cmp, 0))
+      && (cmp->file[1].desc == -1 || dir_loop (cmp, 1)))
+    {
+      error (0, 0, _("%s: recursive directory loop"),
+	     cmp->file[cmp->file[0].desc == -1].name);
+      return EXIT_TROUBLE;
+    }
+
+  /* Get contents of both dirs.  */
+  for (i = 0; i < 2; i++)
+    if (! dir_read (&cmp->file[i], &dirdata[i]))
+      {
+	perror_with_name (cmp->file[i].name);
+	val = EXIT_TROUBLE;
+      }
+
+  if (val == EXIT_SUCCESS)
+    {
+      char const **volatile names[2];
+      names[0] = dirdata[0].names;
+      names[1] = dirdata[1].names;
+
+      /* Use locale-specific sorting if possible, else native byte order.  */
+      locale_specific_sorting = true;
+      if (setjmp (failed_locale_specific_sorting))
+	locale_specific_sorting = false;
+
+      /* Sort the directories.  */
+      for (i = 0; i < 2; i++)
+	qsort (names[i], dirdata[i].nnames, sizeof *dirdata[i].names,
+	       compare_names_for_qsort);
+
+      /* If '-S name' was given, and this is the topmost level of comparison,
+	 ignore all file names less than the specified starting name.  */
+
+      if (starting_file && ! cmp->parent)
+	{
+	  while (*names[0] && compare_names (*names[0], starting_file) < 0)
+	    names[0]++;
+	  while (*names[1] && compare_names (*names[1], starting_file) < 0)
+	    names[1]++;
+	}
+
+      /* Loop while files remain in one or both dirs.  */
+      while (*names[0] || *names[1])
+	{
+	  /* Compare next name in dir 0 with next name in dir 1.
+	     At the end of a dir,
+	     pretend the "next name" in that dir is very large.  */
+	  int nameorder = (!*names[0] ? 1 : !*names[1] ? -1
+			   : compare_names (*names[0], *names[1]));
+
+	  /* Prefer a file_name_cmp match if available.  This algorithm is
+	     O(N**2), where N is the number of names in a directory
+	     that compare_names says are all equal, but in practice N
+	     is so small it's not worth tuning.  */
+	  if (nameorder == 0 && ignore_file_name_case)
+	    {
+	      int raw_order = file_name_cmp (*names[0], *names[1]);
+	      if (raw_order != 0)
+		{
+		  int greater_side = raw_order < 0;
+		  int lesser_side = 1 - greater_side;
+		  char const **lesser = names[lesser_side];
+		  char const *greater_name = *names[greater_side];
+		  char const **p;
+
+		  for (p = lesser + 1;
+		       *p && compare_names (*p, greater_name) == 0;
+		       p++)
+		    {
+		      int c = file_name_cmp (*p, greater_name);
+		      if (0 <= c)
+			{
+			  if (c == 0)
+			    {
+			      memmove (lesser + 1, lesser,
+				       (char *) p - (char *) lesser);
+			      *lesser = greater_name;
+			    }
+			  break;
+			}
+		    }
+		}
+	    }
+
+	  int v1 = (*handle_file) (cmp,
+				   0 < nameorder ? 0 : *names[0]++,
+				   nameorder < 0 ? 0 : *names[1]++);
+	  if (val < v1)
+	    val = v1;
+	}
+    }
+
+  for (i = 0; i < 2; i++)
+    {
+      free (dirdata[i].names);
+      free (dirdata[i].data);
+    }
+
+  return val;
+}
+
+/* Return nonzero if CMP is looping recursively in argument I.  */
+
+static bool _GL_ATTRIBUTE_PURE
+dir_loop (struct comparison const *cmp, int i)
+{
+  struct comparison const *p = cmp;
+  while ((p = p->parent))
+    if (0 < same_file (&p->file[i].stat, &cmp->file[i].stat))
+      return true;
+  return false;
+}
+
+/* Find a matching filename in a directory.  */
+
+char *
+find_dir_file_pathname (char const *dir, char const *file)
+{
+  /* The 'IF_LINT (volatile)' works around what appears to be a bug in
+     gcc 4.8.0 20120825; see
+     <http://lists.gnu.org/archive/html/bug-diffutils/2012-08/msg00007.html>.
+     */
+  char const * IF_LINT (volatile) match = file;
+
+  char *val;
+  struct dirdata dirdata;
+  dirdata.names = NULL;
+  dirdata.data = NULL;
+
+  if (ignore_file_name_case)
+    {
+      struct file_data filedata;
+      filedata.name = dir;
+      filedata.desc = 0;
+
+      if (dir_read (&filedata, &dirdata))
+	{
+	  locale_specific_sorting = true;
+	  if (setjmp (failed_locale_specific_sorting))
+	    match = file; /* longjmp may mess up MATCH.  */
+	  else
+	    {
+	      for (char const **p = dirdata.names; *p; p++)
+		if (compare_names (*p, file) == 0)
+		  {
+		    if (file_name_cmp (*p, file) == 0)
+		      {
+			match = *p;
+			break;
+		      }
+		    if (match == file)
+		      match = *p;
+		  }
+	    }
+	}
+    }
+
+  val = file_name_concat (dir, match, NULL);
+  free (dirdata.names);
+  free (dirdata.data);
+  return val;
+}