sbin/hammer2/subs.c

   1 /*
   2  * Copyright (c) 2011-2012 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Matthew Dillon <dillon@dragonflybsd.org>
   6  * by Venkatesh Srinivas <vsrinivas@dragonflybsd.org>
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  *
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in
  16  *    the documentation and/or other materials provided with the
  17  *    distribution.
  18  * 3. Neither the name of The DragonFly Project nor the names of its
  19  *    contributors may be used to endorse or promote products derived
  20  *    from this software without specific, prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  23  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  24  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  25  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  26  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  27  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  28  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  29  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  30  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  31  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  32  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  */
  35
  36 #include "hammer2.h"
  37
  38 /*
  39  * Obtain a file descriptor that the caller can execute ioctl()'s on.
  40  */
  41 int
  42 hammer2_ioctl_handle(const char *sel_path)
  43 {
  44         struct hammer2_ioc_version info;
  45         int fd;
  46
  47         if (sel_path == NULL)
  48                 sel_path = ".";
  49
  50         fd = open(sel_path, O_RDONLY, 0);
  51         if (fd < 0) {
  52                 fprintf(stderr, "hammer2: Unable to open %s: %s\n",
  53                         sel_path, strerror(errno));
  54                 return(-1);
  55         }
  56         if (ioctl(fd, HAMMER2IOC_VERSION_GET, &info) < 0) {
  57                 fprintf(stderr, "hammer2: '%s' is not a hammer2 filesystem\n",
  58                         sel_path);
  59                 close(fd);
  60                 return(-1);
  61         }
  62         return (fd);
  63 }
  64
  65 /*
  66  * Execute the specified function as a detached independent process/daemon,
  67  * unless we are in debug mode.  If we are in debug mode the function is
  68  * executed as a pthread in the current process.
  69  */
  70 void
  71 hammer2_demon(void *(*func)(void *), void *arg)
  72 {
  73         pthread_t thread = NULL;
  74         pid_t pid;
  75         int ttyfd;
  76
  77         /*
  78          * Do not disconnect in debug mode
  79          */
  80         if (DebugOpt) {
  81                 pthread_create(&thread, NULL, func, arg);
  82                 NormalExit = 0;
  83                 return;
  84         }
  85
  86         /*
  87          * Otherwise disconnect us.  Double-fork to get rid of the ppid
  88          * association and disconnect the TTY.
  89          */
  90         if ((pid = fork()) < 0) {
  91                 fprintf(stderr, "hammer2: fork(): %s\n", strerror(errno));
  92                 exit(1);
  93         }
  94         if (pid > 0) {
  95                 while (waitpid(pid, NULL, 0) != pid)
  96                         ;
  97                 return;         /* parent returns */
  98         }
  99
 100         /*
 101          * Get rid of the TTY/session before double-forking to finish off
 102          * the ppid.
 103          */
 104         ttyfd = open("/dev/null", O_RDWR);
 105         if (ttyfd >= 0) {
 106                 if (ttyfd != 0)
 107                         dup2(ttyfd, 0);
 108                 if (ttyfd != 1)
 109                         dup2(ttyfd, 1);
 110                 if (ttyfd != 2)
 111                         dup2(ttyfd, 2);
 112                 if (ttyfd > 2)
 113                         close(ttyfd);
 114         }
 115
 116         ttyfd = open("/dev/tty", O_RDWR);
 117         if (ttyfd >= 0) {
 118                 ioctl(ttyfd, TIOCNOTTY, 0);
 119                 close(ttyfd);
 120         }
 121         setsid();
 122
 123         /*
 124          * Second fork to disconnect ppid (the original parent waits for
 125          * us to exit).
 126          */
 127         if ((pid = fork()) < 0) {
 128                 _exit(2);
 129         }
 130         if (pid > 0)
 131                 _exit(0);
 132
 133         /*
 134          * The double child
 135          */
 136         setsid();
 137         pthread_create(&thread, NULL, func, arg);
 138         pthread_exit(NULL);
 139         _exit(2);       /* NOT REACHED */
 140 }
 141
 142 const char *
 143 hammer2_time64_to_str(uint64_t htime64, char **strp)
 144 {
 145         struct tm *tp;
 146         time_t t;
 147
 148         if (*strp) {
 149                 free(*strp);
 150                 *strp = NULL;
 151         }
 152         *strp = malloc(64);
 153         t = htime64 / 1000000;
 154         tp = localtime(&t);
 155         strftime(*strp, 64, "%d-%b-%Y %H:%M:%S", tp);
 156         return (*strp);
 157 }
 158
 159 const char *
 160 hammer2_uuid_to_str(uuid_t *uuid, char **strp)
 161 {
 162         uint32_t status;
 163         if (*strp) {
 164                 free(*strp);
 165                 *strp = NULL;
 166         }
 167         uuid_to_string(uuid, strp, &status);
 168         return (*strp);
 169 }
 170
 171 const char *
 172 hammer2_iptype_to_str(uint8_t type)
 173 {
 174         switch(type) {
 175         case HAMMER2_OBJTYPE_UNKNOWN:
 176                 return("UNKNOWN");
 177         case HAMMER2_OBJTYPE_DIRECTORY:
 178                 return("DIR");
 179         case HAMMER2_OBJTYPE_REGFILE:
 180                 return("FILE");
 181         case HAMMER2_OBJTYPE_FIFO:
 182                 return("FIFO");
 183         case HAMMER2_OBJTYPE_CDEV:
 184                 return("CDEV");
 185         case HAMMER2_OBJTYPE_BDEV:
 186                 return("BDEV");
 187         case HAMMER2_OBJTYPE_SOFTLINK:
 188                 return("SOFTLINK");
 189         case HAMMER2_OBJTYPE_HARDLINK:
 190                 return("HARDLINK");
 191         case HAMMER2_OBJTYPE_SOCKET:
 192                 return("SOCKET");
 193         case HAMMER2_OBJTYPE_WHITEOUT:
 194                 return("WHITEOUT");
 195         default:
 196                 return("ILLEGAL");
 197         }
 198 }
 199
 200 const char *
 201 hammer2_pfstype_to_str(uint8_t type)
 202 {
 203         switch(type) {
 204         case HAMMER2_PFSTYPE_NONE:
 205                 return("NONE");
 206         case HAMMER2_PFSTYPE_SUPROOT:
 207                 return("SUPROOT");
 208         case HAMMER2_PFSTYPE_DUMMY:
 209                 return("DUMMY");
 210         case HAMMER2_PFSTYPE_CACHE:
 211                 return("CACHE");
 212         case HAMMER2_PFSTYPE_SLAVE:
 213                 return("SLAVE");
 214         case HAMMER2_PFSTYPE_SOFT_SLAVE:
 215                 return("SOFT_SLAVE");
 216         case HAMMER2_PFSTYPE_SOFT_MASTER:
 217                 return("SOFT_MASTER");
 218         case HAMMER2_PFSTYPE_MASTER:
 219                 return("MASTER");
 220         default:
 221                 return("ILLEGAL");
 222         }
 223 }
 224
 225 const char *
 226 sizetostr(hammer2_off_t size)
 227 {
 228         static char buf[32];
 229
 230         if (size < 1024 / 2) {
 231                 snprintf(buf, sizeof(buf), "%6.2f", (double)size);
 232         } else if (size < 1024 * 1024 / 2) {
 233                 snprintf(buf, sizeof(buf), "%6.2fKB",
 234                         (double)size / 1024);
 235         } else if (size < 1024 * 1024 * 1024LL / 2) {
 236                 snprintf(buf, sizeof(buf), "%6.2fMB",
 237                         (double)size / (1024 * 1024));
 238         } else if (size < 1024 * 1024 * 1024LL * 1024LL / 2) {
 239                 snprintf(buf, sizeof(buf), "%6.2fGB",
 240                         (double)size / (1024 * 1024 * 1024LL));
 241         } else {
 242                 snprintf(buf, sizeof(buf), "%6.2fTB",
 243                         (double)size / (1024 * 1024 * 1024LL * 1024LL));
 244         }
 245         return(buf);
 246 }
 247
 248 const char *
 249 counttostr(hammer2_off_t size)
 250 {
 251         static char buf[32];
 252
 253         if (size < 1024 / 2) {
 254                 snprintf(buf, sizeof(buf), "%jd",
 255                          (intmax_t)size);
 256         } else if (size < 1024 * 1024 / 2) {
 257                 snprintf(buf, sizeof(buf), "%jd",
 258                          (intmax_t)size);
 259         } else if (size < 1024 * 1024 * 1024LL / 2) {
 260                 snprintf(buf, sizeof(buf), "%6.2fM",
 261                          (double)size / (1024 * 1024));
 262         } else if (size < 1024 * 1024 * 1024LL * 1024LL / 2) {
 263                 snprintf(buf, sizeof(buf), "%6.2fG",
 264                          (double)(size / (1024 * 1024 * 1024LL)));
 265         } else {
 266                 snprintf(buf, sizeof(buf), "%6.2fT",
 267                          (double)(size / (1024 * 1024 * 1024LL * 1024LL)));
 268         }
 269         return(buf);
 270 }
 271
 272 #if 0
 273 /*
 274  * Allocation wrappers give us shims for possible future use
 275  */
 276 void *
 277 hammer2_alloc(size_t bytes)
 278 {
 279         void *ptr;
 280
 281         ptr = malloc(bytes);
 282         assert(ptr);
 283         bzero(ptr, bytes);
 284         return (ptr);
 285 }
 286
 287 void
 288 hammer2_free(void *ptr)
 289 {
 290         free(ptr);
 291 }
 292
 293 #endif
 294
 295 hammer2_key_t
 296 dirhash(const unsigned char *name, size_t len)
 297 {
 298         const unsigned char *aname = name;
 299         uint32_t crcx;
 300         uint64_t key;
 301         size_t i;
 302         size_t j;
 303
 304         /*
 305          * Filesystem version 6 or better will create directories
 306          * using the ALG1 dirhash.  This hash breaks the filename
 307          * up into domains separated by special characters and
 308          * hashes each domain independently.
 309          *
 310          * We also do a simple sub-sort using the first character
 311          * of the filename in the top 5-bits.
 312          */
 313         key = 0;
 314
 315         /*
 316          * m32
 317          */
 318         crcx = 0;
 319         for (i = j = 0; i < len; ++i) {
 320                 if (aname[i] == '.' ||
 321                     aname[i] == '-' ||
 322                     aname[i] == '_' ||
 323                     aname[i] == '~') {
 324                         if (i != j)
 325                                 crcx += hammer2_icrc32(aname + j, i - j);
 326                         j = i + 1;
 327                 }
 328         }
 329         if (i != j)
 330                 crcx += hammer2_icrc32(aname + j, i - j);
 331
 332         /*
 333          * The directory hash utilizes the top 32 bits of the 64-bit key.
 334          * Bit 63 must be set to 1.
 335          */
 336         crcx |= 0x80000000U;
 337         key |= (uint64_t)crcx << 32;
 338
 339         /*
 340          * l16 - crc of entire filename
 341          *
 342          * This crc reduces degenerate hash collision conditions
 343          */
 344         crcx = hammer2_icrc32(aname, len);
 345         crcx = crcx ^ (crcx << 16);
 346         key |= crcx & 0xFFFF0000U;
 347
 348         /*
 349          * Set bit 15.  This allows readdir to strip bit 63 so a positive
 350          * 64-bit cookie/offset can always be returned, and still guarantee
 351          * that the values 0x0000-0x7FFF are available for artificial entries.
 352          * ('.' and '..').
 353          */
 354         key |= 0x8000U;
 355
 356         return (key);
 357 }