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 #ifdef _WIN32 37 #define CLOSEDIR_VOID 1 38 #endif 39 40 static int 41 dir_sort (dir, dirdata) 42 struct file_data const *dir; 43 struct dirdata *dirdata; 44 { 45 register struct dirent *next; 46 register int i; 47 48 /* Address of block containing the files that are described. */ 49 char const **names; 50 51 /* Number of files in directory. */ 52 size_t nnames; 53 54 /* Allocated and used storage for file name data. */ 55 char *data; 56 size_t data_alloc, data_used; 57 58 dirdata->names = 0; 59 dirdata->data = 0; 60 nnames = 0; 61 data = 0; 62 63 if (dir->desc != -1) 64 { 65 /* Open the directory and check for errors. */ 66 register DIR *reading = opendir (dir->name); 67 if (!reading) 68 return -1; 69 70 /* Initialize the table of filenames. */ 71 72 data_alloc = max (1, (size_t) dir->stat.st_size); 73 data_used = 0; 74 dirdata->data = data = xmalloc (data_alloc); 75 76 /* Read the directory entries, and insert the subfiles 77 into the `data' table. */ 78 79 while ((errno = 0, (next = readdir (reading)) != 0)) 80 { 81 char *d_name = next->d_name; 82 size_t d_size = NAMLEN (next) + 1; 83 84 /* Ignore the files `.' and `..' */ 85 if (d_name[0] == '.' 86 && (d_name[1] == 0 || (d_name[1] == '.' && d_name[2] == 0))) 87 continue; 88 89 if (excluded_filename (d_name)) 90 continue; 91 92 while (data_alloc < data_used + d_size) 93 dirdata->data = data = xrealloc (data, data_alloc *= 2); 94 memcpy (data + data_used, d_name, d_size); 95 data_used += d_size; 96 nnames++; 97 } 98 if (errno) 99 { 100 int e = errno; 101 closedir (reading); 102 errno = e; 103 return -1; 104 } 105 #if CLOSEDIR_VOID 106 closedir (reading); 107 #else 108 if (closedir (reading) != 0) 109 return -1; 110 #endif 111 } 112 113 /* Create the `names' table from the `data' table. */ 114 dirdata->names = names = (char const **) xmalloc (sizeof (char *) 115 * (nnames + 1)); 116 for (i = 0; i < nnames; i++) 117 { 118 names[i] = data; 119 data += strlen (data) + 1; 120 } 121 names[nnames] = 0; 122 123 /* Sort the table. */ 124 qsort (names, nnames, sizeof (char *), compare_names); 125 126 return 0; 127 } 128 129 /* Sort the files now in the table. */ 130 131 static int 132 compare_names (file1, file2) 133 void const *file1, *file2; 134 { 135 return filename_cmp (* (char const *const *) file1, 136 * (char const *const *) file2); 137 } 138 139 /* Compare the contents of two directories named in FILEVEC[0] and FILEVEC[1]. 140 This is a top-level routine; it does everything necessary for diff 141 on two directories. 142 143 FILEVEC[0].desc == -1 says directory FILEVEC[0] doesn't exist, 144 but pretend it is empty. Likewise for FILEVEC[1]. 145 146 HANDLE_FILE is a caller-provided subroutine called to handle each file. 147 It gets five operands: dir and name (rel to original working dir) of file 148 in dir 0, dir and name pathname of file in dir 1, and the recursion depth. 149 150 For a file that appears in only one of the dirs, one of the name-args 151 to HANDLE_FILE is zero. 152 153 DEPTH is the current depth in recursion, used for skipping top-level 154 files by the -S option. 155 156 Returns the maximum of all the values returned by HANDLE_FILE, 157 or 2 if trouble is encountered in opening files. */ 158 159 int 160 diff_dirs (filevec, handle_file, depth) 161 struct file_data const filevec[]; 162 int (*handle_file) PARAMS((char const *, char const *, char const *, char const *, int)); 163 int depth; 164 { 165 struct dirdata dirdata[2]; 166 int val = 0; /* Return value. */ 167 int i; 168 169 /* Get sorted contents of both dirs. */ 170 for (i = 0; i < 2; i++) 171 if (dir_sort (&filevec[i], &dirdata[i]) != 0) 172 { 173 perror_with_name (filevec[i].name); 174 val = 2; 175 } 176 177 if (val == 0) 178 { 179 register char const * const *names0 = dirdata[0].names; 180 register char const * const *names1 = dirdata[1].names; 181 char const *name0 = filevec[0].name; 182 char const *name1 = filevec[1].name; 183 184 /* If `-S name' was given, and this is the topmost level of comparison, 185 ignore all file names less than the specified starting name. */ 186 187 if (dir_start_file && depth == 0) 188 { 189 while (*names0 && filename_cmp (*names0, dir_start_file) < 0) 190 names0++; 191 while (*names1 && filename_cmp (*names1, dir_start_file) < 0) 192 names1++; 193 } 194 195 /* Loop while files remain in one or both dirs. */ 196 while (*names0 || *names1) 197 { 198 /* Compare next name in dir 0 with next name in dir 1. 199 At the end of a dir, 200 pretend the "next name" in that dir is very large. */ 201 int nameorder = (!*names0 ? 1 : !*names1 ? -1 202 : filename_cmp (*names0, *names1)); 203 int v1 = (*handle_file) (name0, 0 < nameorder ? 0 : *names0++, 204 name1, nameorder < 0 ? 0 : *names1++, 205 depth + 1); 206 if (v1 > val) 207 val = v1; 208 } 209 } 210 211 for (i = 0; i < 2; i++) 212 { 213 if (dirdata[i].names) 214 free (dirdata[i].names); 215 if (dirdata[i].data) 216 free (dirdata[i].data); 217 } 218 219 return val; 220 } 221