1 #define _FILE_OFFSET_BITS 64 2 #define _LARGEFILE_SOURCE 3 #define _LARGEFILE64_SOURCE 4 5 #include <unistd.h> 6 #ifndef _POSIX_SOURCE 7 #define _POSIX_SOURCE 8 #endif 9 #include <stdio.h> 10 #include <stdlib.h> 11 #ifdef HAVE_MALLOC_H 12 #include <malloc.h> 13 #endif 14 #include <string.h> 15 #include <fcntl.h> 16 #include <sys/param.h> 17 #include <sys/types.h> 18 #include <sys/stat.h> 19 #include <dirent.h> 20 #include <time.h> 21 #include <stddef.h> 22 #include <errno.h> 23 24 #ifndef S_ISLNK 25 #define S_ISLNK(mode) (((mode) & (_S_IFMT)) == (_S_IFLNK)) 26 #endif 27 28 #ifndef PATH_MAX 29 #define PATH_MAX 1024 30 #endif 31 32 #define progver "%s: scan/change symbolic links - v1.3 - by Mark Lord\n\n" 33 static char *progname; 34 static int verbose = 0, fix_links = 0, recurse = 0, delete = 0, shorten = 0, 35 testing = 0, single_fs = 1; 36 37 /* 38 * tidypath removes excess slashes and "." references from a path string 39 */ 40 41 static int substr (char *s, char *old, char *new) 42 { 43 char *tmp = NULL; 44 int oldlen = strlen(old), newlen = 0; 45 46 if (NULL == strstr(s, old)) 47 return 0; 48 49 if (new) 50 newlen = strlen(new); 51 52 if (newlen > oldlen) { 53 if ((tmp = malloc(strlen(s))) == NULL) { 54 fprintf(stderr, "no memory\n"); 55 exit (1); 56 } 57 } 58 59 while (NULL != (s = strstr(s, old))) { 60 char *p, *old_s = s; 61 62 if (new) { 63 if (newlen > oldlen) 64 old_s = strcpy(tmp, s); 65 p = new; 66 while (*p) 67 *s++ = *p++; 68 } 69 p = old_s + oldlen; 70 while ((*s++ = *p++)); 71 } 72 if (tmp) 73 free(tmp); 74 return 1; 75 } 76 77 78 static int tidy_path (char *path) 79 { 80 int tidied = 0; 81 char *s, *p; 82 83 s = path + strlen(path) - 1; 84 if (s[0] != '/') { /* tmp trailing slash simplifies things */ 85 s[1] = '/'; 86 s[2] = '\0'; 87 } 88 while (substr(path, "/./", "/")) 89 tidied = 1; 90 while (substr(path, "//", "/")) 91 tidied = 1; 92 93 while ((p = strstr(path,"/../")) != NULL) { 94 s = p+3; 95 for (p--; p != path; p--) if (*p == '/') break; 96 if (*p != '/') 97 break; 98 while ((*p++ = *s++)); 99 tidied = 1; 100 } 101 if (*path == '\0') 102 strcpy(path,"/"); 103 p = path + strlen(path) - 1; 104 if (p != path && *p == '/') 105 *p-- = '\0'; /* remove tmp trailing slash */ 106 while (p != path && *p == '/') { /* remove any others */ 107 *p-- = '\0'; 108 tidied = 1; 109 } 110 while (!strncmp(path,"./",2)) { 111 for (p = path, s = path+2; (*p++ = *s++);); 112 tidied = 1; 113 } 114 return tidied; 115 } 116 117 static int shorten_path (char *path, char *abspath) 118 { 119 static char dir[PATH_MAX]; 120 int shortened = 0; 121 char *p; 122 123 /* get rid of unnecessary "../dir" sequences */ 124 while (abspath && strlen(abspath) > 1 && (p = strstr(path,"../"))) { 125 /* find innermost occurance of "../dir", and save "dir" */ 126 int slashes = 2; 127 char *a, *s, *d = dir; 128 while ((s = strstr(p+3, "../"))) { 129 ++slashes; 130 p = s; 131 } 132 s = p+3; 133 *d++ = '/'; 134 while (*s && *s != '/') 135 *d++ = *s++; 136 *d++ = '/'; 137 *d = '\0'; 138 if (!strcmp(dir,"//")) 139 break; 140 /* note: p still points at ../dir */ 141 if (*s != '/' || !*++s) 142 break; 143 a = abspath + strlen(abspath) - 1; 144 while (slashes-- > 0) { 145 if (a <= abspath) 146 goto ughh; 147 while (*--a != '/') { 148 if (a <= abspath) 149 goto ughh; 150 } 151 } 152 if (strncmp(dir, a, strlen(dir))) 153 break; 154 while ((*p++ = *s++)); /* delete the ../dir */ 155 shortened = 1; 156 } 157 ughh: 158 return shortened; 159 } 160 161 162 static void fix_symlink (char *path, dev_t my_dev) 163 { 164 static char lpath[PATH_MAX], new[PATH_MAX], abspath[PATH_MAX]; 165 char *p, *np, *lp, *tail, *msg; 166 struct stat stbuf, lstbuf; 167 int c, fix_abs = 0, fix_messy = 0, fix_long = 0; 168 169 if ((c = readlink(path, lpath, sizeof(lpath))) == -1) { 170 perror(path); 171 return; 172 } 173 lpath[c] = '\0'; /* readlink does not null terminate it */ 174 175 /* construct the absolute address of the link */ 176 abspath[0] = '\0'; 177 if (lpath[0] != '/') { 178 strcat(abspath,path); 179 c = strlen(abspath); 180 if ((c > 0) && (abspath[c-1] == '/')) 181 abspath[c-1] = '\0'; /* cut trailing / */ 182 if ((p = strrchr(abspath,'/')) != NULL) 183 *p = '\0'; /* cut last component */ 184 strcat(abspath,"/"); 185 } 186 strcat(abspath,lpath); 187 (void) tidy_path(abspath); 188 189 /* check for various things */ 190 if (stat(abspath, &stbuf) == -1) { 191 printf("dangling: %s -> %s\n", path, lpath); 192 if (delete) { 193 if (unlink (path)) { 194 perror(path); 195 } else 196 printf("deleted: %s -> %s\n", path, lpath); 197 } 198 return; 199 } 200 201 if (single_fs) 202 lstat(abspath, &lstbuf); /* if the above didn't fail, then this shouldn't */ 203 204 if (single_fs && lstbuf.st_dev != my_dev) { 205 msg = "other_fs:"; 206 } else if (lpath[0] == '/') { 207 msg = "absolute:"; 208 fix_abs = 1; 209 } else if (verbose) { 210 msg = "relative:"; 211 } else 212 msg = NULL; 213 fix_messy = tidy_path(strcpy(new,lpath)); 214 if (shorten) 215 fix_long = shorten_path(new, path); 216 if (!fix_abs) { 217 if (fix_messy) 218 msg = "messy: "; 219 else if (fix_long) 220 msg = "lengthy: "; 221 } 222 if (msg != NULL) 223 printf("%s %s -> %s\n", msg, path, lpath); 224 if (!(fix_links || testing) || !(fix_messy || fix_abs || fix_long)) 225 return; 226 227 if (fix_abs) { 228 /* convert an absolute link to relative: */ 229 /* point tail at first part of lpath that differs from path */ 230 /* point p at first part of path that differs from lpath */ 231 (void) tidy_path(lpath); 232 tail = lp = lpath; 233 p = path; 234 while (*p && (*p == *lp)) { 235 if (*lp++ == '/') { 236 tail = lp; 237 while (*++p == '/'); 238 } 239 } 240 241 /* now create new, with "../"s followed by tail */ 242 np = new; 243 while (*p) { 244 if (*p++ == '/') { 245 *np++ = '.'; 246 *np++ = '.'; 247 *np++ = '/'; 248 while (*p == '/') ++p; 249 } 250 } 251 strcpy (np, tail); 252 (void) tidy_path(new); 253 if (shorten) (void) shorten_path(new, path); 254 } 255 shorten_path(new,path); 256 if (!testing) { 257 if (unlink (path)) { 258 perror(path); 259 return; 260 } 261 if (symlink(new, path)) { 262 perror(path); 263 return; 264 } 265 } 266 printf("changed: %s -> %s\n", path, new); 267 } 268 269 static void dirwalk (char *path, int pathlen, dev_t dev) 270 { 271 char *name; 272 DIR *dfd; 273 static struct stat st; 274 static struct dirent *dp; 275 276 if ((dfd = opendir(path)) == NULL) { 277 perror(path); 278 return; 279 } 280 281 name = path + pathlen; 282 if (*(name-1) != '/') 283 *name++ = '/'; 284 285 while ((dp = readdir(dfd)) != NULL ) { 286 strcpy(name, dp->d_name); 287 if (strcmp(name, ".") && strcmp(name,"..")) { 288 if (lstat(path, &st) == -1) { 289 perror(path); 290 } else if (st.st_dev == dev) { 291 if (S_ISLNK(st.st_mode)) { 292 fix_symlink (path, dev); 293 } else if (recurse && S_ISDIR(st.st_mode)) { 294 dirwalk(path, strlen(path), dev); 295 } 296 } 297 } 298 } 299 closedir(dfd); 300 path[pathlen] = '\0'; 301 } 302 303 static void usage_error (void) 304 { 305 fprintf(stderr, progver, progname); 306 fprintf(stderr, "Usage:\t%s [-cdorstv] LINK|DIR ...\n\n", progname); 307 fprintf(stderr, "Flags:" 308 "\t-c == change absolute/messy links to relative\n" 309 "\t-d == delete dangling links\n" 310 "\t-o == warn about links across file systems\n" 311 "\t-r == recurse into subdirs\n" 312 "\t-s == shorten lengthy links (displayed in output only when -c not specified)\n" 313 "\t-t == show what would be done by -c\n" 314 "\t-v == verbose (show all symlinks)\n\n"); 315 exit(1); 316 } 317 318 int main(int argc, char **argv) 319 { 320 #if defined (_GNU_SOURCE) && defined (__GLIBC__) 321 static char path[PATH_MAX+2]; 322 char* cwd = get_current_dir_name(); 323 #else 324 static char path[PATH_MAX+2], cwd[PATH_MAX+2]; 325 #endif 326 int dircount = 0; 327 char c, *p; 328 329 if ((progname = (char *) strrchr(*argv, '/')) == NULL) 330 progname = *argv; 331 else 332 progname++; 333 334 #if defined (_GNU_SOURCE) && defined (__GLIBC__) 335 if (NULL == cwd) { 336 fprintf(stderr,"get_current_dir_name() failed\n"); 337 #else 338 if (NULL == getcwd(cwd,PATH_MAX)) { 339 fprintf(stderr,"getcwd() failed\n"); 340 #endif 341 exit (1); 342 } 343 #if defined (_GNU_SOURCE) && defined (__GLIBC__) 344 cwd = realloc(cwd, strlen(cwd)+2); 345 if (cwd == NULL) { 346 fprintf(stderr, "realloc() failed\n"); 347 exit (1); 348 } 349 #endif 350 if (!*cwd || cwd[strlen(cwd)-1] != '/') 351 strcat(cwd,"/"); 352 353 while (--argc) { 354 p = *++argv; 355 if (*p == '-') { 356 if (*++p == '\0') 357 usage_error(); 358 while ((c = *p++)) { 359 if (c == 'c') fix_links = 1; 360 else if (c == 'd') delete = 1; 361 else if (c == 'o') single_fs = 0; 362 else if (c == 'r') recurse = 1; 363 else if (c == 's') shorten = 1; 364 else if (c == 't') testing = 1; 365 else if (c == 'v') verbose = 1; 366 else usage_error(); 367 } 368 } else { 369 struct stat st; 370 if (*p == '/') 371 *path = '\0'; 372 else 373 strcpy(path,cwd); 374 tidy_path(strcat(path, p)); 375 if (lstat(path, &st) == -1) 376 perror(path); 377 else if (S_ISLNK(st.st_mode)) 378 fix_symlink(path, st.st_dev); 379 else 380 dirwalk(path, strlen(path), st.st_dev); 381 ++dircount; 382 } 383 } 384 if (dircount == 0) 385 usage_error(); 386 exit (0); 387 } 388
