1 /* Read, sort and compare two directories. Used for GNU DIFF. 2 Copyright (C) 1988, 1989, 1992, 1993, 1994 Free Software Foundation, Inc. 3 4 This file is part of GNU DIFF. 5 6 GNU DIFF is free software; you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 2, or (at your option) 9 any later version. 10 11 GNU DIFF is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 GNU General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with GNU DIFF; see the file COPYING. If not, write to 18 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ 19 20 #include "diff.h" 21 22 /* Read the directory named by DIR and store into DIRDATA a sorted vector 23 of filenames for its contents. DIR->desc == -1 means this directory is 24 known to be nonexistent, so set DIRDATA to an empty vector. 25 Return -1 (setting errno) if error, 0 otherwise. */ 26 27 struct dirdata 28 { 29 char const **names; /* Sorted names of files in dir, 0-terminated. */ 30 char *data; /* Allocated storage for file names. */ 31 }; 32 33 static int compare_names PARAMS((void const *, void const *)); 34 static int dir_sort PARAMS((struct file_data const *, struct dirdata *)); 35 36 static int 37 dir_sort (dir, dirdata) 38 struct file_data const *dir; 39 struct dirdata *dirdata; 40 { 41 register struct dirent *next; 42 register int i; 43 44 /* Address of block containing the files that are described. */ 45 char const **names; 46 47 /* Number of files in directory. */ 48 size_t nnames; 49 50 /* Allocated and used storage for file name data. */ 51 char *data; 52 size_t data_alloc, data_used; 53 54 dirdata->names = 0; 55 dirdata->data = 0; 56 nnames = 0; 57 data = 0; 58 59 if (dir->desc != -1) 60 { 61 /* Open the directory and check for errors. */ 62 register DIR *reading = opendir (dir->name); 63 if (!reading) 64 return -1; 65 66 /* Initialize the table of filenames. */ 67 68 data_alloc = max (1, (size_t) dir->stat.st_size); 69 data_used = 0; 70 dirdata->data = data = xmalloc (data_alloc); 71 72 /* Read the directory entries, and insert the subfiles 73 into the `data' table. */ 74 75 while ((errno = 0, (next = readdir (reading)) != 0)) 76 { 77 char *d_name = next->d_name; 78 size_t d_size = NAMLEN (next) + 1; 79 80 /* Ignore the files `.' and `..' */ 81 if (d_name[0] == '.' 82 && (d_name[1] == 0 || (d_name[1] == '.' && d_name[2] == 0))) 83 continue; 84 85 if (excluded_filename (d_name)) 86 continue; 87 88 while (data_alloc < data_used + d_size) 89 dirdata->data = data = xrealloc (data, data_alloc *= 2); 90 memcpy (data + data_used, d_name, d_size); 91 data_used += d_size; 92 nnames++; 93 } 94 if (errno) 95 { 96 int e = errno; 97 closedir (reading); 98 errno = e; 99 return -1; 100 } 101 #if CLOSEDIR_VOID 102 closedir (reading); 103 #else 104 if (closedir (reading) != 0) 105 return -1; 106 #endif 107 } 108 109 /* Create the `names' table from the `data' table. */ 110 dirdata->names = names = (char const **) xmalloc (sizeof (char *) 111 * (nnames + 1)); 112 for (i = 0; i < nnames; i++) 113 { 114 names[i] = data; 115 data += strlen (data) + 1; 116 } 117 names[nnames] = 0; 118 119 /* Sort the table. */ 120 qsort (names, nnames, sizeof (char *), compare_names); 121 122 return 0; 123 } 124 125 /* Sort the files now in the table. */ 126 127 static int 128 compare_names (file1, file2) 129 void const *file1, *file2; 130 { 131 return filename_cmp (* (char const *const *) file1, 132 * (char const *const *) file2); 133 } 134 135 /* Compare the contents of two directories named in FILEVEC[0] and FILEVEC[1]. 136 This is a top-level routine; it does everything necessary for diff 137 on two directories. 138 139 FILEVEC[0].desc == -1 says directory FILEVEC[0] doesn't exist, 140 but pretend it is empty. Likewise for FILEVEC[1]. 141 142 HANDLE_FILE is a caller-provided subroutine called to handle each file. 143 It gets five operands: dir and name (rel to original working dir) of file 144 in dir 0, dir and name pathname of file in dir 1, and the recursion depth. 145 146 For a file that appears in only one of the dirs, one of the name-args 147 to HANDLE_FILE is zero. 148 149 DEPTH is the current depth in recursion, used for skipping top-level 150 files by the -S option. 151 152 Returns the maximum of all the values returned by HANDLE_FILE, 153 or 2 if trouble is encountered in opening files. */ 154 155 int 156 diff_dirs (filevec, handle_file, depth) 157 struct file_data const filevec[]; 158 int (*handle_file) PARAMS((char const *, char const *, char const *, char const *, int)); 159 int depth; 160 { 161 struct dirdata dirdata[2]; 162 int val = 0; /* Return value. */ 163 int i; 164 165 /* Get sorted contents of both dirs. */ 166 for (i = 0; i < 2; i++) 167 if (dir_sort (&filevec[i], &dirdata[i]) != 0) 168 { 169 perror_with_name (filevec[i].name); 170 val = 2; 171 } 172 173 if (val == 0) 174 { 175 register char const * const *names0 = dirdata[0].names; 176 register char const * const *names1 = dirdata[1].names; 177 char const *name0 = filevec[0].name; 178 char const *name1 = filevec[1].name; 179 180 /* If `-S name' was given, and this is the topmost level of comparison, 181 ignore all file names less than the specified starting name. */ 182 183 if (dir_start_file && depth == 0) 184 { 185 while (*names0 && filename_cmp (*names0, dir_start_file) < 0) 186 names0++; 187 while (*names1 && filename_cmp (*names1, dir_start_file) < 0) 188 names1++; 189 } 190 191 /* Loop while files remain in one or both dirs. */ 192 while (*names0 || *names1) 193 { 194 /* Compare next name in dir 0 with next name in dir 1. 195 At the end of a dir, 196 pretend the "next name" in that dir is very large. */ 197 int nameorder = (!*names0 ? 1 : !*names1 ? -1 198 : filename_cmp (*names0, *names1)); 199 int v1 = (*handle_file) (name0, 0 < nameorder ? 0 : *names0++, 200 name1, nameorder < 0 ? 0 : *names1++, 201 depth + 1); 202 if (v1 > val) 203 val = v1; 204 } 205 } 206 207 for (i = 0; i < 2; i++) 208 { 209 if (dirdata[i].names) 210 free (dirdata[i].names); 211 if (dirdata[i].data) 212 free (dirdata[i].data); 213 } 214 215 return val; 216 } 217