| 1 | /* Copyright (c) 1979 Regents of the University of California */ |
| 2 | #include <stdio.h> |
| 3 | #include <ctype.h> |
| 4 | #include <sys/types.h> |
| 5 | #include <sys/stat.h> |
| 6 | #include <sys/dir.h> |
| 7 | #include <pwd.h> |
| 8 | #include "local/uparm.h" |
| 9 | |
| 10 | /* |
| 11 | * Expreserve - preserve a file in usrpath(preserve) |
| 12 | * Bill Joy UCB November 13, 1977 |
| 13 | * |
| 14 | * This routine is very naive - it doesn't remove anything from |
| 15 | * usrpath(preserve)... this may mean that we will be unable to preserve |
| 16 | * stuff there... the danger in doing anything with usrpath(preserve) |
| 17 | * is that the clock may be screwed up and we may get confused. |
| 18 | * |
| 19 | * We are called in two ways - first from the editor with no argumentss |
| 20 | * and the standard input open on the temp file. Second with an argument |
| 21 | * to preserve the entire contents of /tmp (root only). |
| 22 | * |
| 23 | * BUG: should do something about preserving Rx... (register contents) |
| 24 | * temporaries. |
| 25 | */ |
| 26 | |
| 27 | #define LBLKS 125 |
| 28 | #define FNSIZE 128 |
| 29 | |
| 30 | struct header { |
| 31 | time_t Time; /* Time temp file last updated */ |
| 32 | short Uid; /* This users identity */ |
| 33 | short Flines; /* Number of lines in file */ |
| 34 | char Savedfile[FNSIZE]; /* The current file name */ |
| 35 | short Blocks[LBLKS]; /* Blocks where line pointers stashed */ |
| 36 | } H; |
| 37 | |
| 38 | #ifdef lint |
| 39 | #define ignore(a) Ignore(a) |
| 40 | #define ignorl(a) Ignorl(a) |
| 41 | #else |
| 42 | #define ignore(a) a |
| 43 | #define ignorl(a) a |
| 44 | #endif |
| 45 | |
| 46 | struct passwd *getpwuid(); |
| 47 | off_t lseek(); |
| 48 | FILE *popen(); |
| 49 | |
| 50 | #define eq(a, b) strcmp(a, b) == 0 |
| 51 | |
| 52 | main(argc) |
| 53 | int argc; |
| 54 | { |
| 55 | register FILE *tf; |
| 56 | struct direct dirent; |
| 57 | struct stat stbuf; |
| 58 | |
| 59 | /* |
| 60 | * If only one argument, then preserve the standard input. |
| 61 | */ |
| 62 | if (argc == 1) { |
| 63 | if (copyout((char *) 0)) |
| 64 | exit(1); |
| 65 | exit(0); |
| 66 | } |
| 67 | |
| 68 | /* |
| 69 | * If not super user, then can only preserve standard input. |
| 70 | */ |
| 71 | if (getuid()) { |
| 72 | fprintf(stderr, "NOT super user\n"); |
| 73 | exit(1); |
| 74 | } |
| 75 | |
| 76 | /* |
| 77 | * ... else preserve all the stuff in /tmp, removing |
| 78 | * it as we go. |
| 79 | */ |
| 80 | if (chdir("/tmp") < 0) { |
| 81 | perror("/tmp"); |
| 82 | exit(1); |
| 83 | } |
| 84 | |
| 85 | tf = fopen(".", "r"); |
| 86 | if (tf == NULL) { |
| 87 | perror("/tmp"); |
| 88 | exit(1); |
| 89 | } |
| 90 | while (fread((char *) &dirent, sizeof dirent, 1, tf) == 1) { |
| 91 | if (dirent.d_ino == 0) |
| 92 | continue; |
| 93 | /* |
| 94 | * Ex temporaries must begin with Ex; |
| 95 | * we check that the 10th character of the name is null |
| 96 | * so we won't have to worry about non-null terminated names |
| 97 | * later on. |
| 98 | */ |
| 99 | if (dirent.d_name[0] != 'E' || dirent.d_name[1] != 'x' || dirent.d_name[10]) |
| 100 | continue; |
| 101 | if (stat(dirent.d_name, &stbuf)) |
| 102 | continue; |
| 103 | if ((stbuf.st_mode & S_IFMT) != S_IFREG) |
| 104 | continue; |
| 105 | /* |
| 106 | * Save the bastard. |
| 107 | */ |
| 108 | ignore(copyout(dirent.d_name)); |
| 109 | } |
| 110 | exit(0); |
| 111 | } |
| 112 | |
| 113 | char pattern[] = usrpath(preserve/Exaa`XXXXX); |
| 114 | |
| 115 | /* |
| 116 | * Copy file name into usrpath(preserve)/... |
| 117 | * If name is (char *) 0, then do the standard input. |
| 118 | * We make some checks on the input to make sure it is |
| 119 | * really an editor temporary, generate a name for the |
| 120 | * file (this is the slowest thing since we must stat |
| 121 | * to find a unique name), and finally copy the file. |
| 122 | */ |
| 123 | copyout(name) |
| 124 | char *name; |
| 125 | { |
| 126 | int i; |
| 127 | static int reenter; |
| 128 | char buf[BUFSIZ]; |
| 129 | |
| 130 | /* |
| 131 | * The first time we put in the digits of our |
| 132 | * process number at the end of the pattern. |
| 133 | */ |
| 134 | if (reenter == 0) { |
| 135 | mkdigits(pattern); |
| 136 | reenter++; |
| 137 | } |
| 138 | |
| 139 | /* |
| 140 | * If a file name was given, make it the standard |
| 141 | * input if possible. |
| 142 | */ |
| 143 | if (name != 0) { |
| 144 | ignore(close(0)); |
| 145 | /* |
| 146 | * Need read/write access for arcane reasons |
| 147 | * (see below). |
| 148 | */ |
| 149 | if (open(name, 2) < 0) |
| 150 | return (-1); |
| 151 | } |
| 152 | |
| 153 | /* |
| 154 | * Get the header block. |
| 155 | */ |
| 156 | ignorl(lseek(0, 0l, 0)); |
| 157 | if (read(0, (char *) &H, sizeof H) != sizeof H) { |
| 158 | format: |
| 159 | if (name == 0) |
| 160 | fprintf(stderr, "Buffer format error\n"); |
| 161 | return (-1); |
| 162 | } |
| 163 | |
| 164 | /* |
| 165 | * Consistency checsks so we don't copy out garbage. |
| 166 | */ |
| 167 | if (H.Flines < 0) { |
| 168 | #ifdef DEBUG |
| 169 | fprintf(stderr, "Negative number of lines\n"); |
| 170 | #endif |
| 171 | goto format; |
| 172 | } |
| 173 | if (H.Blocks[0] != 1 || H.Blocks[1] != 2) { |
| 174 | #ifdef DEBUG |
| 175 | fprintf(stderr, "Blocks %d %d\n", H.Blocks[0], H.Blocks[1]); |
| 176 | #endif |
| 177 | goto format; |
| 178 | } |
| 179 | if (name == 0 && H.Uid != getuid()) { |
| 180 | #ifdef DEBUG |
| 181 | fprintf(stderr, "Wrong user-id\n"); |
| 182 | #endif |
| 183 | goto format; |
| 184 | } |
| 185 | if (lseek(0, 0l, 0)) { |
| 186 | #ifdef DEBUG |
| 187 | fprintf(stderr, "Negative number of lines\n"); |
| 188 | #endif |
| 189 | goto format; |
| 190 | } |
| 191 | |
| 192 | /* |
| 193 | * If no name was assigned to the file, then give it the name |
| 194 | * LOST, by putting this in the header. |
| 195 | */ |
| 196 | if (H.Savedfile[0] == 0) { |
| 197 | strcpy(H.Savedfile, "LOST"); |
| 198 | ignore(write(0, (char *) &H, sizeof H)); |
| 199 | H.Savedfile[0] = 0; |
| 200 | lseek(0, 0l, 0); |
| 201 | } |
| 202 | |
| 203 | /* |
| 204 | * File is good. Get a name and create a file for the copy. |
| 205 | */ |
| 206 | mknext(pattern); |
| 207 | ignore(close(1)); |
| 208 | if (creat(pattern, 0600) < 0) { |
| 209 | if (name == 0) |
| 210 | perror(pattern); |
| 211 | return (1); |
| 212 | } |
| 213 | |
| 214 | /* |
| 215 | * Make the target be owned by the owner of the file. |
| 216 | */ |
| 217 | ignore(chown(pattern, H.Uid, 0)); |
| 218 | |
| 219 | /* |
| 220 | * Copy the file. |
| 221 | */ |
| 222 | for (;;) { |
| 223 | i = read(0, buf, BUFSIZ); |
| 224 | if (i < 0) { |
| 225 | if (name) |
| 226 | perror("Buffer read error"); |
| 227 | ignore(unlink(pattern)); |
| 228 | return (-1); |
| 229 | } |
| 230 | if (i == 0) { |
| 231 | if (name) |
| 232 | ignore(unlink(name)); |
| 233 | notify(H.Uid, H.Savedfile, (int) name); |
| 234 | return (0); |
| 235 | } |
| 236 | if (write(1, buf, i) != i) { |
| 237 | if (name == 0) |
| 238 | perror(pattern); |
| 239 | unlink(pattern); |
| 240 | return (-1); |
| 241 | } |
| 242 | } |
| 243 | } |
| 244 | |
| 245 | /* |
| 246 | * Blast the last 5 characters of cp to be the process number. |
| 247 | */ |
| 248 | mkdigits(cp) |
| 249 | char *cp; |
| 250 | { |
| 251 | register int i, j; |
| 252 | |
| 253 | for (i = getpid(), j = 5, cp += strlen(cp); j > 0; i /= 10, j--) |
| 254 | *--cp = i % 10 | '0'; |
| 255 | } |
| 256 | |
| 257 | /* |
| 258 | * Make the name in cp be unique by clobbering up to |
| 259 | * three alphabetic characters into a sequence of the form 'aab', 'aac', etc. |
| 260 | * Mktemp gets weird names too quickly to be useful here. |
| 261 | */ |
| 262 | mknext(cp) |
| 263 | char *cp; |
| 264 | { |
| 265 | char *dcp; |
| 266 | struct stat stb; |
| 267 | |
| 268 | dcp = cp + strlen(cp) - 1; |
| 269 | while (isdigit(*dcp)) |
| 270 | dcp--; |
| 271 | whoops: |
| 272 | if (dcp[0] == 'z') { |
| 273 | dcp[0] = 'a'; |
| 274 | if (dcp[-1] == 'z') { |
| 275 | dcp[-1] = 'a'; |
| 276 | if (dcp[-2] == 'z') |
| 277 | fprintf(stderr, "Can't find a name\n"); |
| 278 | dcp[-2]++; |
| 279 | } else |
| 280 | dcp[-1]++; |
| 281 | } else |
| 282 | dcp[0]++; |
| 283 | if (stat(cp, &stb) == 0) |
| 284 | goto whoops; |
| 285 | } |
| 286 | |
| 287 | /* |
| 288 | * Notify user uid that his file fname has been saved. |
| 289 | */ |
| 290 | notify(uid, fname, flag) |
| 291 | int uid; |
| 292 | char *fname; |
| 293 | { |
| 294 | struct passwd *pp = getpwuid(uid); |
| 295 | register FILE *mf; |
| 296 | char cmd[BUFSIZ]; |
| 297 | |
| 298 | if (pp == NULL) |
| 299 | return; |
| 300 | sprintf(cmd, "mail %s", pp->pw_name); |
| 301 | mf = popen(cmd, "w"); |
| 302 | if (mf == NULL) |
| 303 | return; |
| 304 | setbuf(mf, cmd); |
| 305 | if (fname[0] == 0) { |
| 306 | fprintf(mf, |
| 307 | "A copy of an editor buffer of yours was saved when %s.\n", |
| 308 | flag ? "the system went down" : "your phone was hung up"); |
| 309 | fprintf(mf, |
| 310 | "No name was associated with this buffer so it has been named \"LOST\".\n"); |
| 311 | } else |
| 312 | fprintf(mf, |
| 313 | "A copy of an editor buffer of your file \"%s\"\nwas saved when %s.\n", fname, |
| 314 | flag ? "the system went down" : "your phone was hung up"); |
| 315 | fprintf(mf, |
| 316 | "This buffer can be retrieved using the \"recover\" command of the editor.\n"); |
| 317 | fprintf(mf, |
| 318 | "An easy way to do this is to give the command \"ex -r %s\".\n",fname); |
| 319 | fprintf(mf, |
| 320 | "This works for \"edit\" and \"vi\" also.\n"); |
| 321 | pclose(mf); |
| 322 | } |
| 323 | |
| 324 | /* |
| 325 | * people making love |
| 326 | * never exactly the same |
| 327 | * just like a snowflake |
| 328 | */ |
| 329 | |
| 330 | #ifdef lint |
| 331 | Ignore(a) |
| 332 | int a; |
| 333 | { |
| 334 | |
| 335 | a = a; |
| 336 | } |
| 337 | |
| 338 | Ignorl(a) |
| 339 | long a; |
| 340 | { |
| 341 | |
| 342 | a = a; |
| 343 | } |
| 344 | #endif |