1 /* Read, sort and compare two directories. Used for GNU DIFF.
3 Copyright (C) 1988, 1989, 1992, 1993, 1994, 1995, 1998, 2001, 2002
4 Free Software Foundation, Inc.
6 This file is part of GNU DIFF.
8 GNU DIFF is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2, or (at your option)
13 GNU DIFF is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program; see the file COPYING.
20 If not, write to the Free Software Foundation,
21 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
29 /* Read the directory named by DIR and store into DIRDATA a sorted vector
30 of filenames for its contents. DIR->desc == -1 means this directory is
31 known to be nonexistent, so set DIRDATA to an empty vector.
32 Return -1 (setting errno) if error, 0 otherwise. */
36 size_t nnames; /* Number of names. */
37 char const **names; /* Sorted names of files in dir, followed by 0. */
38 char *data; /* Allocated storage for file names. */
41 /* Whether file names in directories should be compared with strcoll. */
42 static bool locale_specific_sorting;
44 /* Where to go if strcoll fails. */
45 static jmp_buf failed_strcoll;
47 static bool dir_loop (struct comparison const *, int);
48 static int compare_names_for_qsort (void const *, void const *);
51 /* Read a directory and get its vector of names. */
54 dir_read (struct file_data const *dir, struct dirdata *dirdata)
56 register struct dirent *next;
59 /* Address of block containing the files that are described. */
62 /* Number of files in directory. */
65 /* Allocated and used storage for file name data. */
67 size_t data_alloc, data_used;
76 /* Open the directory and check for errors. */
77 register DIR *reading = opendir (dir->name);
81 /* Initialize the table of filenames. */
85 dirdata->data = data = xmalloc (data_alloc);
87 /* Read the directory entries, and insert the subfiles
88 into the `data' table. */
90 while ((errno = 0, (next = readdir (reading)) != 0))
92 char *d_name = next->d_name;
93 size_t d_size = NAMLEN (next) + 1;
95 /* Ignore "." and "..". */
97 && (d_name[1] == 0 || (d_name[1] == '.' && d_name[2] == 0)))
100 if (excluded_filename (excluded, d_name))
103 while (data_alloc < data_used + d_size)
105 if (PTRDIFF_MAX / 2 <= data_alloc)
107 dirdata->data = data = xrealloc (data, data_alloc *= 2);
110 memcpy (data + data_used, d_name, d_size);
124 if (closedir (reading) != 0)
129 /* Create the `names' table from the `data' table. */
130 if (PTRDIFF_MAX / sizeof *names - 1 <= nnames)
132 dirdata->names = names = xmalloc ((nnames + 1) * sizeof *names);
133 dirdata->nnames = nnames;
134 for (i = 0; i < nnames; i++)
137 data += strlen (data) + 1;
143 /* Compare file names, returning a value compatible with strcmp. */
146 compare_names (char const *name1, char const *name2)
148 if (ignore_file_name_case)
150 int r = strcasecmp (name1, name2);
155 if (locale_specific_sorting)
159 r = strcoll (name1, name2);
162 error (0, errno, _("cannot compare file names `%s' and `%s'"),
164 longjmp (failed_strcoll, 1);
170 return file_name_cmp (name1, name2);
173 /* A wrapper for compare_names suitable as an argument for qsort. */
176 compare_names_for_qsort (void const *file1, void const *file2)
178 char const *const *f1 = file1;
179 char const *const *f2 = file2;
180 return compare_names (*f1, *f2);
183 /* Compare the contents of two directories named in CMP.
184 This is a top-level routine; it does everything necessary for diff
187 CMP->file[0].desc == -1 says directory CMP->file[0] doesn't exist,
188 but pretend it is empty. Likewise for CMP->file[1].
190 HANDLE_FILE is a caller-provided subroutine called to handle each file.
191 It gets three operands: CMP, name of file in dir 0, name of file in dir 1.
192 These names are relative to the original working directory.
194 For a file that appears in only one of the dirs, one of the name-args
195 to HANDLE_FILE is zero.
197 Returns the maximum of all the values returned by HANDLE_FILE,
198 or EXIT_TROUBLE if trouble is encountered in opening files. */
201 diff_dirs (struct comparison const *cmp,
202 int (*handle_file) (struct comparison const *,
203 char const *, char const *))
205 struct dirdata dirdata[2];
206 int volatile val = EXIT_SUCCESS;
209 if ((cmp->file[0].desc == -1 || dir_loop (cmp, 0))
210 && (cmp->file[1].desc == -1 || dir_loop (cmp, 1)))
212 error (0, 0, "%s: recursive directory loop",
213 cmp->file[cmp->file[0].desc == -1].name);
217 /* Get contents of both dirs. */
218 for (i = 0; i < 2; i++)
219 if (! dir_read (&cmp->file[i], &dirdata[i]))
221 perror_with_name (cmp->file[i].name);
225 if (val == EXIT_SUCCESS)
227 char const **volatile names[2];
228 names[0] = dirdata[0].names;
229 names[1] = dirdata[1].names;
231 /* Use locale-specific sorting if possible, else native byte order. */
232 locale_specific_sorting = 1;
233 if (setjmp (failed_strcoll))
234 locale_specific_sorting = 0;
236 /* Sort the directories. */
237 for (i = 0; i < 2; i++)
238 qsort (names[i], dirdata[i].nnames, sizeof *dirdata[i].names,
239 compare_names_for_qsort);
241 /* If `-S name' was given, and this is the topmost level of comparison,
242 ignore all file names less than the specified starting name. */
244 if (starting_file && ! cmp->parent)
246 while (*names[0] && compare_names (*names[0], starting_file) < 0)
248 while (*names[1] && compare_names (*names[1], starting_file) < 0)
252 /* Loop while files remain in one or both dirs. */
253 while (*names[0] || *names[1])
255 /* Compare next name in dir 0 with next name in dir 1.
257 pretend the "next name" in that dir is very large. */
258 int nameorder = (!*names[0] ? 1 : !*names[1] ? -1
259 : compare_names (*names[0], *names[1]));
260 int v1 = (*handle_file) (cmp,
261 0 < nameorder ? 0 : *names[0]++,
262 nameorder < 0 ? 0 : *names[1]++);
268 for (i = 0; i < 2; i++)
270 if (dirdata[i].names)
271 free (dirdata[i].names);
273 free (dirdata[i].data);
279 /* Return nonzero if CMP is looping recursively in argument I. */
282 dir_loop (struct comparison const *cmp, int i)
284 struct comparison const *p = cmp;
285 while ((p = p->parent))
286 if (0 < same_file (&p->file[i].stat, &cmp->file[i].stat))