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rpmio/fts.c

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00001 /*@-boundsread@*/
00002 /*@-sysunrecog -noeffectuncon -nullpass -sizeoftype -unrecog -usereleased @*/
00003 /*@-compdef -compmempass -dependenttrans -retalias @*/
00004 /*-
00005  * Copyright (c) 1990, 1993, 1994
00006  *      The Regents of the University of California.  All rights reserved.
00007  *
00008  * Redistribution and use in source and binary forms, with or without
00009  * modification, are permitted provided that the following conditions
00010  * are met:
00011  * 1. Redistributions of source code must retain the above copyright
00012  *    notice, this list of conditions and the following disclaimer.
00013  * 2. Redistributions in binary form must reproduce the above copyright
00014  *    notice, this list of conditions and the following disclaimer in the
00015  *    documentation and/or other materials provided with the distribution.
00016  * 4. Neither the name of the University nor the names of its contributors
00017  *    may be used to endorse or promote products derived from this software
00018  *    without specific prior written permission.
00019  *
00020  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
00021  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
00022  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
00023  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
00024  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
00025  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
00026  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
00027  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
00028  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
00029  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
00030  * SUCH DAMAGE.
00031  */
00032 
00033 #if defined(LIBC_SCCS) && !defined(lint)
00034 static char sccsid[] = "@(#)fts.c       8.6 (Berkeley) 8/14/94";
00035 #endif /* LIBC_SCCS and not lint */
00036 
00037 #if defined(_LIBC)
00038 #include <sys/param.h>
00039 #include <include/sys/stat.h>
00040 #include <fcntl.h>
00041 #include <dirent.h>
00042 #include <errno.h>
00043 #include <fts.h>
00044 #include <stdlib.h>
00045 #include <string.h>
00046 #include <unistd.h>
00047 #else
00048 #if defined(hpux)
00049 # define        _INCLUDE_POSIX_SOURCE
00050 #   define __errno_location()   (&errno)
00051 #   define dirfd(dirp)          -1
00052 #   define stat64               stat
00053 #   define _STAT_VER            0
00054 #   define __fxstat64(_stat_ver, _fd, _sbp)     fstat((_fd), (_sbp))
00055 #endif
00056 #include "system.h"
00057 #include "fts.h"
00058 #include "rpmio.h"
00059 #include "rpmurl.h"
00060 #   define __set_errno(val) (*__errno_location ()) = (val)
00061 #   define __open       open
00062 #   define __close      close
00063 #   define __fchdir     fchdir
00064 #endif
00065 
00066 
00067 /* Largest alignment size needed, minus one.
00068    Usually long double is the worst case.  */
00069 #ifndef ALIGNBYTES
00070 #define ALIGNBYTES      (__alignof__ (long double) - 1)
00071 #endif
00072 /* Align P to that size.  */
00073 #ifndef ALIGN
00074 #define ALIGN(p)        (((unsigned long int) (p) + ALIGNBYTES) & ~ALIGNBYTES)
00075 #endif
00076 
00077 
00078 /*@only@*/
00079 static FTSENT * fts_alloc(FTS * sp, const char * name, int namelen)
00080         /*@*/;
00081 static FTSENT * fts_build(FTS * sp, int type)
00082         /*@globals fileSystem, internalState @*/
00083         /*@modifies *sp, fileSystem, internalState @*/;
00084 static void     fts_lfree(/*@only@*/ FTSENT * head)
00085         /*@modifies head @*/;
00086 static void     fts_load(FTS * sp, FTSENT * p)
00087         /*@modifies *sp, *p @*/;
00088 static size_t   fts_maxarglen(char * const * argv)
00089         /*@*/;
00090 static void     fts_padjust(FTS * sp, FTSENT * head)
00091         /*@modifies *sp, *head @*/;
00092 static int      fts_palloc(FTS * sp, size_t more)
00093         /*@modifies *sp @*/;
00094 static FTSENT * fts_sort(FTS * sp, /*@returned@*/ FTSENT * head, int nitems)
00095         /*@modifies *sp @*/;
00096 static u_short  fts_stat(FTS * sp, FTSENT * p, int follow)
00097         /*@modifies *p @*/;
00098 static int      fts_safe_changedir(FTS * sp, FTSENT * p, int fd,
00099                         const char * path)
00100         /*@globals fileSystem, internalState @*/
00101         /*@modifies fileSystem, internalState @*/;
00102 
00103 #ifndef MAX
00104 #define MAX(a, b)       ({ __typeof__ (a) _a = (a); \
00105                            __typeof__ (b) _b = (b); \
00106                            _a > _b ? _a : _b; })
00107 #endif
00108 
00109 #define ISDOT(a)        (a[0] == '.' && (!a[1] || (a[1] == '.' && !a[2])))
00110 
00111 #define CLR(opt)        (sp->fts_options &= ~(opt))
00112 #define ISSET(opt)      (sp->fts_options & (opt))
00113 #define SET(opt)        (sp->fts_options |= (opt))
00114 
00115 #define FCHDIR(sp, fd)  (!ISSET(FTS_NOCHDIR) && __fchdir(fd))
00116 
00117 /* fts_build flags */
00118 #define BCHILD          1               /* fts_children */
00119 #define BNAMES          2               /* fts_children, names only */
00120 #define BREAD           3               /* fts_read */
00121 
00122 FTS *
00123 Fts_open(char * const * argv, int options,
00124                 int (*compar) (const FTSENT **, const FTSENT **))
00125 {
00126         register FTS *sp;
00127         register FTSENT *p, *root;
00128         register int nitems;
00129         FTSENT *parent, *tmp = NULL;
00130         int len;
00131 
00132         /* Options check. */
00133         if (options & ~FTS_OPTIONMASK) {
00134 /*@-boundswrite@*/
00135                 __set_errno (EINVAL);
00136 /*@=boundswrite@*/
00137                 return (NULL);
00138         }
00139 
00140         /* Allocate/initialize the stream */
00141         if ((sp = malloc((u_int)sizeof(*sp))) == NULL)
00142                 return (NULL);
00143         memset(sp, 0, sizeof(*sp));
00144         sp->fts_compar = (int (*) (const void *, const void *)) compar;
00145         sp->fts_opendir = Opendir;
00146         sp->fts_readdir = Readdir;
00147         sp->fts_closedir = Closedir;
00148         sp->fts_stat = Stat;
00149         sp->fts_lstat = Lstat;
00150         sp->fts_options = options;
00151 
00152         /* Logical walks turn on NOCHDIR; symbolic links are too hard. */
00153         if (ISSET(FTS_LOGICAL))
00154                 SET(FTS_NOCHDIR);
00155 
00156         /*
00157          * Start out with 1K of path space, and enough, in any case,
00158          * to hold the user's paths.
00159          */
00160 #ifndef MAXPATHLEN
00161 #define MAXPATHLEN 1024
00162 #endif
00163         if (fts_palloc(sp, MAX(fts_maxarglen(argv), MAXPATHLEN)))
00164                 goto mem1;
00165 
00166         /* Allocate/initialize root's parent. */
00167         if ((parent = fts_alloc(sp, "", 0)) == NULL)
00168                 goto mem2;
00169         parent->fts_level = FTS_ROOTPARENTLEVEL;
00170 
00171         /* Allocate/initialize root(s). */
00172         for (root = NULL, nitems = 0; *argv != NULL; ++argv, ++nitems) {
00173                 /* Don't allow zero-length paths. */
00174                 if ((len = strlen(*argv)) == 0) {
00175 /*@-boundswrite@*/
00176                         __set_errno (ENOENT);
00177 /*@=boundswrite@*/
00178                         goto mem3;
00179                 }
00180 
00181                 /* Use fchdir(2) speedup only if local DASDI. */
00182                 switch (urlIsURL(*argv)) {
00183                 case URL_IS_DASH:
00184 /*@-boundswrite@*/
00185                         __set_errno (ENOENT);
00186 /*@=boundswrite@*/
00187                         goto mem3;
00188                         /*@notreached@*/ /*@switchbreak@*/ break;
00189                 case URL_IS_HTTP:
00190                 case URL_IS_FTP:
00191                         SET(FTS_NOCHDIR);
00192                         /*@switchbreak@*/ break;
00193                 case URL_IS_UNKNOWN:
00194                 case URL_IS_PATH:
00195                         /*@switchbreak@*/ break;
00196                 }
00197 
00198                 p = fts_alloc(sp, *argv, len);
00199                 p->fts_level = FTS_ROOTLEVEL;
00200                 p->fts_parent = parent;
00201                 p->fts_accpath = p->fts_name;
00202                 p->fts_info = fts_stat(sp, p, ISSET(FTS_COMFOLLOW));
00203 
00204                 /* Command-line "." and ".." are real directories. */
00205                 if (p->fts_info == FTS_DOT)
00206                         p->fts_info = FTS_D;
00207 
00208                 /*
00209                  * If comparison routine supplied, traverse in sorted
00210                  * order; otherwise traverse in the order specified.
00211                  */
00212                 if (compar) {
00213                         p->fts_link = root;
00214                         root = p;
00215                 } else {
00216                         p->fts_link = NULL;
00217                         if (root == NULL)
00218                                 tmp = root = p;
00219                         else {
00220                                 tmp->fts_link = p;
00221                                 tmp = p;
00222                         }
00223                 }
00224         }
00225         /*@-branchstate@*/
00226         if (compar && nitems > 1)
00227                 root = fts_sort(sp, root, nitems);
00228         /*@=branchstate@*/
00229 
00230         /*
00231          * Allocate a dummy pointer and make fts_read think that we've just
00232          * finished the node before the root(s); set p->fts_info to FTS_INIT
00233          * so that everything about the "current" node is ignored.
00234          */
00235         if ((sp->fts_cur = fts_alloc(sp, "", 0)) == NULL)
00236                 goto mem3;
00237         sp->fts_cur->fts_link = root;
00238         sp->fts_cur->fts_info = FTS_INIT;
00239 
00240         /*
00241          * If using chdir(2), grab a file descriptor pointing to dot to ensure
00242          * that we can get back here; this could be avoided for some paths,
00243          * but almost certainly not worth the effort.  Slashes, symbolic links,
00244          * and ".." are all fairly nasty problems.  Note, if we can't get the
00245          * descriptor we run anyway, just more slowly.
00246          */
00247         if (!ISSET(FTS_NOCHDIR)
00248             && (sp->fts_rfd = __open(".", O_RDONLY, 0)) < 0)
00249                 SET(FTS_NOCHDIR);
00250 
00251         return (sp);
00252 
00253 mem3:   fts_lfree(root);
00254         free(parent);
00255 mem2:   free(sp->fts_path);
00256 mem1:   free(sp);
00257         return (NULL);
00258 }
00259 
00260 static void
00261 fts_load(FTS * sp, FTSENT * p)
00262 {
00263         register int len;
00264         register char *cp;
00265 
00266         /*
00267          * Load the stream structure for the next traversal.  Since we don't
00268          * actually enter the directory until after the preorder visit, set
00269          * the fts_accpath field specially so the chdir gets done to the right
00270          * place and the user can access the first node.  From fts_open it's
00271          * known that the path will fit.
00272          */
00273         len = p->fts_pathlen = p->fts_namelen;
00274 /*@-boundswrite@*/
00275         memmove(sp->fts_path, p->fts_name, len + 1);
00276         if ((cp = strrchr(p->fts_name, '/')) && (cp != p->fts_name || cp[1])) {
00277                 len = strlen(++cp);
00278                 memmove(p->fts_name, cp, len + 1);
00279                 p->fts_namelen = len;
00280         }
00281         p->fts_accpath = p->fts_path = sp->fts_path;
00282         sp->fts_dev = p->fts_dev;
00283 /*@=boundswrite@*/
00284 }
00285 
00286 int
00287 Fts_close(FTS * sp)
00288 {
00289         register FTSENT *freep, *p;
00290         int saved_errno;
00291 
00292         /*
00293          * This still works if we haven't read anything -- the dummy structure
00294          * points to the root list, so we step through to the end of the root
00295          * list which has a valid parent pointer.
00296          */
00297         /*@-branchstate@*/
00298         if (sp->fts_cur) {
00299                 for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) {
00300                         freep = p;
00301                         p = p->fts_link != NULL ? p->fts_link : p->fts_parent;
00302                         free(freep);
00303                 }
00304                 free(p);
00305         }
00306         /*@=branchstate@*/
00307 
00308         /* Free up child linked list, sort array, path buffer. */
00309         if (sp->fts_child)
00310                 fts_lfree(sp->fts_child);
00311         if (sp->fts_array)
00312                 free(sp->fts_array);
00313         free(sp->fts_path);
00314 
00315         /* Return to original directory, save errno if necessary. */
00316         if (!ISSET(FTS_NOCHDIR)) {
00317                 saved_errno = __fchdir(sp->fts_rfd) ? errno : 0;
00318                 (void)__close(sp->fts_rfd);
00319 
00320                 /* Set errno and return. */
00321                 if (saved_errno != 0) {
00322                         /* Free up the stream pointer. */
00323                         free(sp);
00324 /*@-boundswrite@*/
00325                         __set_errno (saved_errno);
00326 /*@=boundswrite@*/
00327                         return (-1);
00328                 }
00329         }
00330 
00331         /* Free up the stream pointer. */
00332         free(sp);
00333         return (0);
00334 }
00335 
00336 /*
00337  * Special case of "/" at the end of the path so that slashes aren't
00338  * appended which would cause paths to be written as "....//foo".
00339  */
00340 #define NAPPEND(p)                                                      \
00341         (p->fts_path[p->fts_pathlen - 1] == '/'                         \
00342             ? p->fts_pathlen - 1 : p->fts_pathlen)
00343 
00344 FTSENT *
00345 Fts_read(FTS * sp)
00346 {
00347         register FTSENT *p;
00348         register FTSENT *tmp;
00349         register int instr;
00350         register char *t;
00351         int saved_errno;
00352 
00353         /* If finished or unrecoverable error, return NULL. */
00354         if (sp->fts_cur == NULL || ISSET(FTS_STOP))
00355                 return (NULL);
00356 
00357         /* Set current node pointer. */
00358         p = sp->fts_cur;
00359 
00360         /* Save and zero out user instructions. */
00361         instr = p->fts_instr;
00362         p->fts_instr = FTS_NOINSTR;
00363 
00364         /* Any type of file may be re-visited; re-stat and re-turn. */
00365         if (instr == FTS_AGAIN) {
00366                 p->fts_info = fts_stat(sp, p, 0);
00367                 return (p);
00368         }
00369 
00370         /*
00371          * Following a symlink -- SLNONE test allows application to see
00372          * SLNONE and recover.  If indirecting through a symlink, have
00373          * keep a pointer to current location.  If unable to get that
00374          * pointer, follow fails.
00375          */
00376         if (instr == FTS_FOLLOW &&
00377             (p->fts_info == FTS_SL || p->fts_info == FTS_SLNONE)) {
00378                 p->fts_info = fts_stat(sp, p, 1);
00379                 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {
00380                         if ((p->fts_symfd = __open(".", O_RDONLY, 0)) < 0) {
00381                                 p->fts_errno = errno;
00382                                 p->fts_info = FTS_ERR;
00383                         } else
00384                                 p->fts_flags |= FTS_SYMFOLLOW;
00385                 }
00386                 return (p);
00387         }
00388 
00389         /* Directory in pre-order. */
00390         if (p->fts_info == FTS_D) {
00391                 /* If skipped or crossed mount point, do post-order visit. */
00392                 if (instr == FTS_SKIP ||
00393                     (ISSET(FTS_XDEV) && p->fts_dev != sp->fts_dev)) {
00394                         if (p->fts_flags & FTS_SYMFOLLOW)
00395                                 (void)__close(p->fts_symfd);
00396                         if (sp->fts_child) {
00397                                 fts_lfree(sp->fts_child);
00398                                 sp->fts_child = NULL;
00399                         }
00400                         p->fts_info = FTS_DP;
00401                         return (p);
00402                 }
00403 
00404                 /* Rebuild if only read the names and now traversing. */
00405                 if (sp->fts_child != NULL && ISSET(FTS_NAMEONLY)) {
00406                         CLR(FTS_NAMEONLY);
00407                         fts_lfree(sp->fts_child);
00408                         sp->fts_child = NULL;
00409                 }
00410 
00411                 /*
00412                  * Cd to the subdirectory.
00413                  *
00414                  * If have already read and now fail to chdir, whack the list
00415                  * to make the names come out right, and set the parent errno
00416                  * so the application will eventually get an error condition.
00417                  * Set the FTS_DONTCHDIR flag so that when we logically change
00418                  * directories back to the parent we don't do a chdir.
00419                  *
00420                  * If haven't read do so.  If the read fails, fts_build sets
00421                  * FTS_STOP or the fts_info field of the node.
00422                  */
00423                 if (sp->fts_child != NULL) {
00424                         if (fts_safe_changedir(sp, p, -1, p->fts_accpath)) {
00425                                 p->fts_errno = errno;
00426                                 p->fts_flags |= FTS_DONTCHDIR;
00427                                 for (p = sp->fts_child; p != NULL;
00428                                      p = p->fts_link)
00429                                         p->fts_accpath =
00430                                             p->fts_parent->fts_accpath;
00431                         }
00432                 } else if ((sp->fts_child = fts_build(sp, BREAD)) == NULL) {
00433                         if (ISSET(FTS_STOP))
00434                                 return (NULL);
00435                         return (p);
00436                 }
00437                 p = sp->fts_child;
00438                 sp->fts_child = NULL;
00439                 goto name;
00440         }
00441 
00442         /* Move to the next node on this level. */
00443 /*@-boundswrite@*/
00444 next:   tmp = p;
00445         if ((p = p->fts_link) != NULL) {
00446                 free(tmp);
00447 
00448                 /*
00449                  * If reached the top, return to the original directory (or
00450                  * the root of the tree), and load the paths for the next root.
00451                  */
00452                 if (p->fts_level == FTS_ROOTLEVEL) {
00453                         if (FCHDIR(sp, sp->fts_rfd)) {
00454                                 SET(FTS_STOP);
00455                                 return (NULL);
00456                         }
00457                         fts_load(sp, p);
00458                         return (sp->fts_cur = p);
00459                 }
00460 
00461                 /*
00462                  * User may have called fts_set on the node.  If skipped,
00463                  * ignore.  If followed, get a file descriptor so we can
00464                  * get back if necessary.
00465                  */
00466                 if (p->fts_instr == FTS_SKIP)
00467                         goto next;
00468                 /*@-branchstate@*/
00469                 if (p->fts_instr == FTS_FOLLOW) {
00470                         p->fts_info = fts_stat(sp, p, 1);
00471                         if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {
00472                                 if ((p->fts_symfd =
00473                                     __open(".", O_RDONLY, 0)) < 0) {
00474                                         p->fts_errno = errno;
00475                                         p->fts_info = FTS_ERR;
00476                                 } else
00477                                         p->fts_flags |= FTS_SYMFOLLOW;
00478                         }
00479                         p->fts_instr = FTS_NOINSTR;
00480                 }
00481                 /*@=branchstate@*/
00482 
00483 name:           t = sp->fts_path + NAPPEND(p->fts_parent);
00484                 *t++ = '/';
00485                 memmove(t, p->fts_name, p->fts_namelen + 1);
00486                 return (sp->fts_cur = p);
00487         }
00488 
00489         /* Move up to the parent node. */
00490         p = tmp->fts_parent;
00491         free(tmp);
00492 
00493         if (p->fts_level == FTS_ROOTPARENTLEVEL) {
00494                 /*
00495                  * Done; free everything up and set errno to 0 so the user
00496                  * can distinguish between error and EOF.
00497                  */
00498                 free(p);
00499                 __set_errno (0);
00500                 return (sp->fts_cur = NULL);
00501         }
00502 
00503         /* NUL terminate the pathname. */
00504         sp->fts_path[p->fts_pathlen] = '\0';
00505 /*@=boundswrite@*/
00506 
00507         /*
00508          * Return to the parent directory.  If at a root node or came through
00509          * a symlink, go back through the file descriptor.  Otherwise, cd up
00510          * one directory.
00511          */
00512         if (p->fts_level == FTS_ROOTLEVEL) {
00513                 if (FCHDIR(sp, sp->fts_rfd)) {
00514                         SET(FTS_STOP);
00515                         return (NULL);
00516                 }
00517         } else if (p->fts_flags & FTS_SYMFOLLOW) {
00518                 if (FCHDIR(sp, p->fts_symfd)) {
00519                         saved_errno = errno;
00520                         (void)__close(p->fts_symfd);
00521 /*@-boundswrite@*/
00522                         __set_errno (saved_errno);
00523 /*@=boundswrite@*/
00524                         SET(FTS_STOP);
00525                         return (NULL);
00526                 }
00527                 (void)__close(p->fts_symfd);
00528         } else if (!(p->fts_flags & FTS_DONTCHDIR) &&
00529                    fts_safe_changedir(sp, p->fts_parent, -1, "..")) {
00530                 SET(FTS_STOP);
00531                 return (NULL);
00532         }
00533         p->fts_info = p->fts_errno ? FTS_ERR : FTS_DP;
00534         return (sp->fts_cur = p);
00535 }
00536 
00537 /*
00538  * Fts_set takes the stream as an argument although it's not used in this
00539  * implementation; it would be necessary if anyone wanted to add global
00540  * semantics to fts using fts_set.  An error return is allowed for similar
00541  * reasons.
00542  */
00543 int
00544 Fts_set(/*@unused@*/ FTS * sp, FTSENT * p, int instr)
00545 {
00546         if (instr != 0 && instr != FTS_AGAIN && instr != FTS_FOLLOW &&
00547             instr != FTS_NOINSTR && instr != FTS_SKIP) {
00548 /*@-boundswrite@*/
00549                 __set_errno (EINVAL);
00550 /*@=boundswrite@*/
00551                 return (1);
00552         }
00553         p->fts_instr = instr;
00554         return (0);
00555 }
00556 
00557 FTSENT *
00558 Fts_children(FTS * sp, int instr)
00559 {
00560         register FTSENT *p;
00561         int fd;
00562 
00563         if (instr != 0 && instr != FTS_NAMEONLY) {
00564 /*@-boundswrite@*/
00565                 __set_errno (EINVAL);
00566 /*@=boundswrite@*/
00567                 return (NULL);
00568         }
00569 
00570         /* Set current node pointer. */
00571         p = sp->fts_cur;
00572 
00573         /*
00574          * Errno set to 0 so user can distinguish empty directory from
00575          * an error.
00576          */
00577 /*@-boundswrite@*/
00578         __set_errno (0);
00579 /*@=boundswrite@*/
00580 
00581         /* Fatal errors stop here. */
00582         if (ISSET(FTS_STOP))
00583                 return (NULL);
00584 
00585         /* Return logical hierarchy of user's arguments. */
00586         if (p->fts_info == FTS_INIT)
00587                 return (p->fts_link);
00588 
00589         /*
00590          * If not a directory being visited in pre-order, stop here.  Could
00591          * allow FTS_DNR, assuming the user has fixed the problem, but the
00592          * same effect is available with FTS_AGAIN.
00593          */
00594         if (p->fts_info != FTS_D /* && p->fts_info != FTS_DNR */)
00595                 return (NULL);
00596 
00597         /* Free up any previous child list. */
00598         if (sp->fts_child != NULL)
00599                 fts_lfree(sp->fts_child);
00600 
00601         if (instr == FTS_NAMEONLY) {
00602                 SET(FTS_NAMEONLY);
00603                 instr = BNAMES;
00604         } else
00605                 instr = BCHILD;
00606 
00607         /*
00608          * If using chdir on a relative path and called BEFORE fts_read does
00609          * its chdir to the root of a traversal, we can lose -- we need to
00610          * chdir into the subdirectory, and we don't know where the current
00611          * directory is, so we can't get back so that the upcoming chdir by
00612          * fts_read will work.
00613          */
00614         if (p->fts_level != FTS_ROOTLEVEL || p->fts_accpath[0] == '/' ||
00615             ISSET(FTS_NOCHDIR))
00616                 return (sp->fts_child = fts_build(sp, instr));
00617 
00618         if ((fd = __open(".", O_RDONLY, 0)) < 0)
00619                 return (NULL);
00620         sp->fts_child = fts_build(sp, instr);
00621         if (__fchdir(fd))
00622                 return (NULL);
00623         (void)__close(fd);
00624         return (sp->fts_child);
00625 }
00626 
00627 /*
00628  * This is the tricky part -- do not casually change *anything* in here.  The
00629  * idea is to build the linked list of entries that are used by fts_children
00630  * and fts_read.  There are lots of special cases.
00631  *
00632  * The real slowdown in walking the tree is the stat calls.  If FTS_NOSTAT is
00633  * set and it's a physical walk (so that symbolic links can't be directories),
00634  * we can do things quickly.  First, if it's a 4.4BSD file system, the type
00635  * of the file is in the directory entry.  Otherwise, we assume that the number
00636  * of subdirectories in a node is equal to the number of links to the parent.
00637  * The former skips all stat calls.  The latter skips stat calls in any leaf
00638  * directories and for any files after the subdirectories in the directory have
00639  * been found, cutting the stat calls by about 2/3.
00640  */
00641 static FTSENT *
00642 fts_build(FTS * sp, int type)
00643 {
00644         register struct dirent *dp;
00645         register FTSENT *p, *head;
00646         register int nitems;
00647         FTSENT *cur, *tail;
00648         DIR *dirp;
00649         void *oldaddr;
00650         int cderrno, descend, len, level, maxlen, nlinks, saved_errno,
00651             nostat, doadjust;
00652         char *cp;
00653 
00654         /* Set current node pointer. */
00655         cur = sp->fts_cur;
00656 
00657         /*
00658          * Open the directory for reading.  If this fails, we're done.
00659          * If being called from fts_read, set the fts_info field.
00660          */
00661 #if defined FTS_WHITEOUT && 0
00662         if (ISSET(FTS_WHITEOUT))
00663                 oflag = DTF_NODUP|DTF_REWIND;
00664         else
00665                 oflag = DTF_HIDEW|DTF_NODUP|DTF_REWIND;
00666 #else
00667 # define __opendir2(path, flag) (*sp->fts_opendir) (path)
00668 #endif
00669        if ((dirp = __opendir2(cur->fts_accpath, oflag)) == NULL) {
00670                 if (type == BREAD) {
00671                         cur->fts_info = FTS_DNR;
00672                         cur->fts_errno = errno;
00673                 }
00674                 return (NULL);
00675         }
00676 
00677         /*
00678          * Nlinks is the number of possible entries of type directory in the
00679          * directory if we're cheating on stat calls, 0 if we're not doing
00680          * any stat calls at all, -1 if we're doing stats on everything.
00681          */
00682         if (type == BNAMES) {
00683                 nlinks = 0;
00684                 /* Be quiet about nostat, GCC. */
00685                 nostat = 0;
00686         } else if (ISSET(FTS_NOSTAT) && ISSET(FTS_PHYSICAL)) {
00687                 nlinks = cur->fts_nlink - (ISSET(FTS_SEEDOT) ? 0 : 2);
00688                 nostat = 1;
00689         } else {
00690                 nlinks = -1;
00691                 nostat = 0;
00692         }
00693 
00694 #ifdef notdef
00695         (void)printf("nlinks == %d (cur: %d)\n", nlinks, cur->fts_nlink);
00696         (void)printf("NOSTAT %d PHYSICAL %d SEEDOT %d\n",
00697             ISSET(FTS_NOSTAT), ISSET(FTS_PHYSICAL), ISSET(FTS_SEEDOT));
00698 #endif
00699         /*
00700          * If we're going to need to stat anything or we want to descend
00701          * and stay in the directory, chdir.  If this fails we keep going,
00702          * but set a flag so we don't chdir after the post-order visit.
00703          * We won't be able to stat anything, but we can still return the
00704          * names themselves.  Note, that since fts_read won't be able to
00705          * chdir into the directory, it will have to return different path
00706          * names than before, i.e. "a/b" instead of "b".  Since the node
00707          * has already been visited in pre-order, have to wait until the
00708          * post-order visit to return the error.  There is a special case
00709          * here, if there was nothing to stat then it's not an error to
00710          * not be able to stat.  This is all fairly nasty.  If a program
00711          * needed sorted entries or stat information, they had better be
00712          * checking FTS_NS on the returned nodes.
00713          */
00714         cderrno = 0;
00715         if (nlinks || type == BREAD) {
00716                 if (fts_safe_changedir(sp, cur, dirfd(dirp), NULL)) {
00717                         if (nlinks && type == BREAD)
00718                                 cur->fts_errno = errno;
00719                         cur->fts_flags |= FTS_DONTCHDIR;
00720                         descend = 0;
00721                         cderrno = errno;
00722                         (void) (*sp->fts_closedir) (dirp);
00723                         dirp = NULL;
00724                 } else
00725                         descend = 1;
00726         } else
00727                 descend = 0;
00728 
00729         /*
00730          * Figure out the max file name length that can be stored in the
00731          * current path -- the inner loop allocates more path as necessary.
00732          * We really wouldn't have to do the maxlen calculations here, we
00733          * could do them in fts_read before returning the path, but it's a
00734          * lot easier here since the length is part of the dirent structure.
00735          *
00736          * If not changing directories set a pointer so that can just append
00737          * each new name into the path.
00738          */
00739         len = NAPPEND(cur);
00740         if (ISSET(FTS_NOCHDIR)) {
00741                 cp = sp->fts_path + len;
00742 /*@-boundswrite@*/
00743                 *cp++ = '/';
00744 /*@=boundswrite@*/
00745         } else {
00746                 /* GCC, you're too verbose. */
00747                 cp = NULL;
00748         }
00749         len++;
00750         maxlen = sp->fts_pathlen - len;
00751 
00752         level = cur->fts_level + 1;
00753 
00754         /* Read the directory, attaching each entry to the `link' pointer. */
00755         doadjust = 0;
00756         for (head = tail = NULL, nitems = 0;
00757              dirp && (dp = (*sp->fts_readdir) (dirp));)
00758         {
00759                 if (!ISSET(FTS_SEEDOT) && ISDOT(dp->d_name))
00760                         continue;
00761 
00762                 if ((p = fts_alloc(sp, dp->d_name, (int)_D_EXACT_NAMLEN (dp))) == NULL)
00763                         goto mem1;
00764                 if (_D_EXACT_NAMLEN (dp) >= maxlen) {/* include space for NUL */
00765                         oldaddr = sp->fts_path;
00766                         if (fts_palloc(sp, _D_EXACT_NAMLEN (dp) + len + 1)) {
00767                                 /*
00768                                  * No more memory for path or structures.  Save
00769                                  * errno, free up the current structure and the
00770                                  * structures already allocated.
00771                                  */
00772 mem1:                           saved_errno = errno;
00773                                 if (p)
00774                                         free(p);
00775                                 fts_lfree(head);
00776                                 (void) (*sp->fts_closedir) (dirp);
00777                                 cur->fts_info = FTS_ERR;
00778                                 SET(FTS_STOP);
00779                                 __set_errno (saved_errno);
00780                                 return (NULL);
00781                         }
00782                         /* Did realloc() change the pointer? */
00783                         if (oldaddr != sp->fts_path) {
00784                                 doadjust = 1;
00785                                 if (ISSET(FTS_NOCHDIR))
00786                                         cp = sp->fts_path + len;
00787                         }
00788                         maxlen = sp->fts_pathlen - len;
00789                 }
00790 
00791                 if (len + _D_EXACT_NAMLEN (dp) >= USHRT_MAX) {
00792                         /*
00793                          * In an FTSENT, fts_pathlen is a u_short so it is
00794                          * possible to wraparound here.  If we do, free up
00795                          * the current structure and the structures already
00796                          * allocated, then error out with ENAMETOOLONG.
00797                          */
00798                         free(p);
00799                         fts_lfree(head);
00800                         (void) (*sp->fts_closedir) (dirp);
00801                         cur->fts_info = FTS_ERR;
00802                         SET(FTS_STOP);
00803                         __set_errno (ENAMETOOLONG);
00804                         return (NULL);
00805                 }
00806                 p->fts_level = level;
00807                 p->fts_parent = sp->fts_cur;
00808                 p->fts_pathlen = len + _D_EXACT_NAMLEN (dp);
00809 
00810 #if defined FTS_WHITEOUT && 0
00811                 if (dp->d_type == DT_WHT)
00812                         p->fts_flags |= FTS_ISW;
00813 #endif
00814 
00815                 if (cderrno) {
00816                         if (nlinks) {
00817                                 p->fts_info = FTS_NS;
00818                                 p->fts_errno = cderrno;
00819                         } else
00820                                 p->fts_info = FTS_NSOK;
00821                         p->fts_accpath = cur->fts_accpath;
00822                 } else if (nlinks == 0
00823 #if defined DT_DIR && defined _DIRENT_HAVE_D_TYPE
00824                            || (nostat &&
00825                                dp->d_type != DT_DIR && dp->d_type != DT_UNKNOWN)
00826 #endif
00827                     ) {
00828                         p->fts_accpath =
00829                             ISSET(FTS_NOCHDIR) ? p->fts_path : p->fts_name;
00830                         p->fts_info = FTS_NSOK;
00831                 } else {
00832                         /* Build a file name for fts_stat to stat. */
00833                         if (ISSET(FTS_NOCHDIR)) {
00834                                 p->fts_accpath = p->fts_path;
00835                                 memmove(cp, p->fts_name, p->fts_namelen + 1);
00836                         } else
00837                                 p->fts_accpath = p->fts_name;
00838                         /* Stat it. */
00839                         p->fts_info = fts_stat(sp, p, 0);
00840 
00841                         /* Decrement link count if applicable. */
00842                         if (nlinks > 0 && (p->fts_info == FTS_D ||
00843                             p->fts_info == FTS_DC || p->fts_info == FTS_DOT))
00844                                 --nlinks;
00845                 }
00846 
00847                 /* We walk in directory order so "ls -f" doesn't get upset. */
00848                 p->fts_link = NULL;
00849                 if (head == NULL)
00850                         head = tail = p;
00851                 else {
00852                         tail->fts_link = p;
00853                         tail = p;
00854                 }
00855                 ++nitems;
00856         }
00857         if (dirp)
00858                 (void) (*sp->fts_closedir) (dirp);
00859 
00860         /*
00861          * If realloc() changed the address of the path, adjust the
00862          * addresses for the rest of the tree and the dir list.
00863          */
00864         if (doadjust)
00865                 fts_padjust(sp, head);
00866 
00867         /*
00868          * If not changing directories, reset the path back to original
00869          * state.
00870          */
00871         if (ISSET(FTS_NOCHDIR)) {
00872                 if (len == sp->fts_pathlen || nitems == 0)
00873                         --cp;
00874 /*@-boundswrite@*/
00875                 *cp = '\0';
00876 /*@=boundswrite@*/
00877         }
00878 
00879         /*
00880          * If descended after called from fts_children or after called from
00881          * fts_read and nothing found, get back.  At the root level we use
00882          * the saved fd; if one of fts_open()'s arguments is a relative path
00883          * to an empty directory, we wind up here with no other way back.  If
00884          * can't get back, we're done.
00885          */
00886         if (descend && (type == BCHILD || !nitems) &&
00887             (cur->fts_level == FTS_ROOTLEVEL ?
00888              FCHDIR(sp, sp->fts_rfd) :
00889              fts_safe_changedir(sp, cur->fts_parent, -1, ".."))) {
00890                 cur->fts_info = FTS_ERR;
00891                 SET(FTS_STOP);
00892                 return (NULL);
00893         }
00894 
00895         /* If didn't find anything, return NULL. */
00896         if (!nitems) {
00897                 if (type == BREAD)
00898                         cur->fts_info = FTS_DP;
00899                 return (NULL);
00900         }
00901 
00902         /* Sort the entries. */
00903         if (sp->fts_compar && nitems > 1)
00904                 head = fts_sort(sp, head, nitems);
00905         return (head);
00906 }
00907 
00908 static u_short
00909 fts_stat(FTS * sp, FTSENT * p, int follow)
00910 {
00911         register FTSENT *t;
00912         register dev_t dev;
00913         register ino_t ino;
00914         struct stat *sbp, sb;
00915         int saved_errno;
00916 
00917         /* If user needs stat info, stat buffer already allocated. */
00918         sbp = ISSET(FTS_NOSTAT) ? &sb : p->fts_statp;
00919 
00920 #if defined FTS_WHITEOUT && 0
00921         /* check for whiteout */
00922         if (p->fts_flags & FTS_ISW) {
00923                 if (sbp != &sb) {
00924                         memset(sbp, '\0', sizeof (*sbp));
00925                         sbp->st_mode = S_IFWHT;
00926                 }
00927                 return (FTS_W);
00928        }
00929 #endif
00930 
00931         /*
00932          * If doing a logical walk, or application requested FTS_FOLLOW, do
00933          * a stat(2).  If that fails, check for a non-existent symlink.  If
00934          * fail, set the errno from the stat call.
00935          */
00936         if (ISSET(FTS_LOGICAL) || follow) {
00937                 if ((*sp->fts_stat) (p->fts_accpath, sbp)) {
00938                         saved_errno = errno;
00939                         if (!(*sp->fts_lstat) (p->fts_accpath, sbp)) {
00940 /*@-boundswrite@*/
00941                                 __set_errno (0);
00942 /*@=boundswrite@*/
00943                                 return (FTS_SLNONE);
00944                         }
00945                         p->fts_errno = saved_errno;
00946                         goto err;
00947                 }
00948         } else if ((*sp->fts_lstat) (p->fts_accpath, sbp)) {
00949                 p->fts_errno = errno;
00950 /*@-boundswrite@*/
00951 err:            memset(sbp, 0, sizeof(*sbp));
00952 /*@=boundswrite@*/
00953                 return (FTS_NS);
00954         }
00955 
00956         if (S_ISDIR(sbp->st_mode)) {
00957                 /*
00958                  * Set the device/inode.  Used to find cycles and check for
00959                  * crossing mount points.  Also remember the link count, used
00960                  * in fts_build to limit the number of stat calls.  It is
00961                  * understood that these fields are only referenced if fts_info
00962                  * is set to FTS_D.
00963                  */
00964                 dev = p->fts_dev = sbp->st_dev;
00965                 ino = p->fts_ino = sbp->st_ino;
00966                 p->fts_nlink = sbp->st_nlink;
00967 
00968                 if (ISDOT(p->fts_name))
00969                         return (FTS_DOT);
00970 
00971                 /*
00972                  * Cycle detection is done by brute force when the directory
00973                  * is first encountered.  If the tree gets deep enough or the
00974                  * number of symbolic links to directories is high enough,
00975                  * something faster might be worthwhile.
00976                  */
00977                 for (t = p->fts_parent;
00978                     t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent)
00979                         if (ino == t->fts_ino && dev == t->fts_dev) {
00980                                 p->fts_cycle = t;
00981                                 return (FTS_DC);
00982                         }
00983                 return (FTS_D);
00984         }
00985         if (S_ISLNK(sbp->st_mode))
00986                 return (FTS_SL);
00987         if (S_ISREG(sbp->st_mode))
00988                 return (FTS_F);
00989         return (FTS_DEFAULT);
00990 }
00991 
00992 static FTSENT *
00993 fts_sort(FTS * sp, FTSENT * head, int nitems)
00994 {
00995         register FTSENT **ap, *p;
00996 
00997         /*
00998          * Construct an array of pointers to the structures and call qsort(3).
00999          * Reassemble the array in the order returned by qsort.  If unable to
01000          * sort for memory reasons, return the directory entries in their
01001          * current order.  Allocate enough space for the current needs plus
01002          * 40 so don't realloc one entry at a time.
01003          */
01004         if (nitems > sp->fts_nitems) {
01005                 struct _ftsent **a;
01006 
01007                 sp->fts_nitems = nitems + 40;
01008                 if ((a = realloc(sp->fts_array,
01009                     (size_t)(sp->fts_nitems * sizeof(*sp->fts_array)))) == NULL)
01010                 {
01011                         free(sp->fts_array);
01012                         sp->fts_array = NULL;
01013                         sp->fts_nitems = 0;
01014                         return (head);
01015                 }
01016                 sp->fts_array = a;
01017         }
01018 /*@-boundswrite@*/
01019         for (ap = sp->fts_array, p = head; p; p = p->fts_link)
01020                 *ap++ = p;
01021         qsort((void *)sp->fts_array, nitems, sizeof(*sp->fts_array),
01022                 sp->fts_compar);
01023         for (head = *(ap = sp->fts_array); --nitems; ++ap)
01024                 ap[0]->fts_link = ap[1];
01025         ap[0]->fts_link = NULL;
01026 /*@=boundswrite@*/
01027         return (head);
01028 }
01029 
01030 static FTSENT *
01031 fts_alloc(FTS * sp, const char * name, int namelen)
01032 {
01033         register FTSENT *p;
01034         size_t len;
01035 
01036         /*
01037          * The file name is a variable length array and no stat structure is
01038          * necessary if the user has set the nostat bit.  Allocate the FTSENT
01039          * structure, the file name and the stat structure in one chunk, but
01040          * be careful that the stat structure is reasonably aligned.  Since the
01041          * fts_name field is declared to be of size 1, the fts_name pointer is
01042          * namelen + 2 before the first possible address of the stat structure.
01043          */
01044         len = sizeof(*p) + namelen;
01045         if (!ISSET(FTS_NOSTAT))
01046                 len += sizeof(*p->fts_statp) + ALIGNBYTES;
01047         if ((p = malloc(len)) == NULL)
01048                 return (NULL);
01049 
01050         /* Copy the name and guarantee NUL termination. */
01051 /*@-boundswrite@*/
01052         memmove(p->fts_name, name, namelen);
01053         p->fts_name[namelen] = '\0';
01054 /*@=boundswrite@*/
01055 
01056         if (!ISSET(FTS_NOSTAT))
01057                 p->fts_statp = (struct stat *)ALIGN(p->fts_name + namelen + 2);
01058         p->fts_namelen = namelen;
01059         p->fts_path = sp->fts_path;
01060         p->fts_errno = 0;
01061         p->fts_flags = 0;
01062         p->fts_instr = FTS_NOINSTR;
01063         p->fts_number = 0;
01064         p->fts_pointer = NULL;
01065         return (p);
01066 }
01067 
01068 static void
01069 fts_lfree(FTSENT * head)
01070 {
01071         register FTSENT *p;
01072 
01073         /* Free a linked list of structures. */
01074         /*@-branchstate@*/
01075         while ((p = head)) {
01076                 head = head->fts_link;
01077                 free(p);
01078         }
01079         /*@=branchstate@*/
01080 }
01081 
01082 /*
01083  * Allow essentially unlimited paths; find, rm, ls should all work on any tree.
01084  * Most systems will allow creation of paths much longer than MAXPATHLEN, even
01085  * though the kernel won't resolve them.  Add the size (not just what's needed)
01086  * plus 256 bytes so don't realloc the path 2 bytes at a time.
01087  */
01088 static int
01089 fts_palloc(FTS * sp, size_t more)
01090 {
01091         char *p;
01092 
01093         sp->fts_pathlen += more + 256;
01094         /*
01095          * Check for possible wraparound.  In an FTS, fts_pathlen is
01096          * a signed int but in an FTSENT it is an unsigned short.
01097          * We limit fts_pathlen to USHRT_MAX to be safe in both cases.
01098          */
01099         if (sp->fts_pathlen < 0 || sp->fts_pathlen >= USHRT_MAX) {
01100                 if (sp->fts_path) {
01101                         free(sp->fts_path);
01102                         sp->fts_path = NULL;
01103                 }
01104                 sp->fts_path = NULL;
01105 /*@-boundswrite@*/
01106                 __set_errno (ENAMETOOLONG);
01107 /*@=boundswrite@*/
01108                 return (1);
01109         }
01110         p = realloc(sp->fts_path, sp->fts_pathlen);
01111         if (p == NULL) {
01112                 free(sp->fts_path);
01113                 sp->fts_path = NULL;
01114                 return 1;
01115         }
01116         sp->fts_path = p;
01117         return 0;
01118 }
01119 
01120 /*
01121  * When the path is realloc'd, have to fix all of the pointers in structures
01122  * already returned.
01123  */
01124 static void
01125 fts_padjust(FTS * sp, FTSENT * head)
01126 {
01127         FTSENT *p;
01128         char *addr = sp->fts_path;
01129 
01130 #define ADJUST(p) do {                                                  \
01131         if ((p)->fts_accpath != (p)->fts_name) {                        \
01132                 (p)->fts_accpath =                                      \
01133                     (char *)addr + ((p)->fts_accpath - (p)->fts_path);  \
01134         }                                                               \
01135         (p)->fts_path = addr;                                           \
01136 } while (0)
01137         /* Adjust the current set of children. */
01138         for (p = sp->fts_child; p; p = p->fts_link)
01139                 ADJUST(p);
01140 
01141         /* Adjust the rest of the tree, including the current level. */
01142         for (p = head; p->fts_level >= FTS_ROOTLEVEL;) {
01143                 ADJUST(p);
01144                 p = p->fts_link ? p->fts_link : p->fts_parent;
01145         }
01146 }
01147 
01148 static size_t
01149 fts_maxarglen(char * const * argv)
01150 {
01151         size_t len, max;
01152 
01153         for (max = 0; *argv; ++argv)
01154                 if ((len = strlen(*argv)) > max)
01155                         max = len;
01156         return (max + 1);
01157 }
01158 
01159 /*
01160  * Change to dir specified by fd or p->fts_accpath without getting
01161  * tricked by someone changing the world out from underneath us.
01162  * Assumes p->fts_dev and p->fts_ino are filled in.
01163  */
01164 static int
01165 fts_safe_changedir(FTS * sp, FTSENT * p, int fd, const char * path)
01166 {
01167         int ret, oerrno, newfd;
01168         struct stat64 sb;
01169 
01170         newfd = fd;
01171         if (ISSET(FTS_NOCHDIR))
01172                 return (0);
01173         if (fd < 0 && (newfd = __open(path, O_RDONLY, 0)) < 0)
01174                 return (-1);
01175         if (__fxstat64(_STAT_VER, newfd, &sb)) {
01176                 ret = -1;
01177                 goto bail;
01178         }
01179         if (p->fts_dev != sb.st_dev || p->fts_ino != sb.st_ino) {
01180 /*@-boundswrite@*/
01181                 __set_errno (ENOENT);           /* disinformation */
01182 /*@=boundswrite@*/
01183                 ret = -1;
01184                 goto bail;
01185         }
01186         ret = __fchdir(newfd);
01187 bail:
01188         oerrno = errno;
01189         if (fd < 0)
01190                 (void)__close(newfd);
01191 /*@-boundswrite@*/
01192         __set_errno (oerrno);
01193 /*@=boundswrite@*/
01194         return (ret);
01195 }
01196 /*@=compdef =compmempass =dependenttrans =retalias @*/
01197 /*@=sysunrecog =noeffectuncon =nullpass =sizeoftype =unrecog =usereleased @*/
01198 /*@=boundsread@*/

Generated on Tue Sep 17 15:56:45 2002 for rpm by doxygen1.2.14 written by Dimitri van Heesch, © 1997-2002