ctags/main/portable-scandir.c

   1 #include "general.h"
   2 /*
   3  * Taken from https://github.com/ClusterLabs/pacemaker/blob/master/replace/scandir.c
   4  */
   5
   6 /* scandir: Scan a directory, collecting all (selected) items into a an array.
   7  *
   8  * This code borrowed from 'libit', which can be found here:
   9  *
  10  * http://www.iro.umontreal.ca/~pinard/libit/dist/scandir/
  11  *
  12  * The original author put this code in the public domain.
  13  * It has been modified slightly to get rid of warnings, etc.
  14  *
  15  * Below is the email I received from pinard@iro.umontreal.ca (François Pinard)
  16  * when I sent him an email asking him about the license, etc. of this
  17  * code which I obtained from his site.
  18  *
  19  * I think the correct spelling of his name is Rich Salz.  I think he's now
  20  * rsalz@datapower.com...
  21  * --
  22  * Rich Salz, Chief Security Architect
  23  * DataPower Technology                           http://www.datapower.com
  24  * XS40 XML Security Gateway   http://www.datapower.com/products/xs40.html
  25  *
  26  *      Copyright(C):   none (public domain)
  27  *      License:        none (public domain)
  28  *      Author:         Rich Salz <rsalz@datapower.com>
  29  *
  30  *
  31  *
  32  *      -- Alan Robertson
  33  *         alanr@unix.sh
  34  *
  35  **************************************************************************
  36  *
  37  * Subject:     Re: Scandir replacement function
  38  * Date:        18 May 2001 12:00:48 -0400
  39  * From:        pinard@iro.umontreal.ca (François Pinard)
  40  * To:          Alan Robertson <alanr@unix.sh>
  41  * References:  1
  42  *
  43  *
  44  * [Alan Robertson]
  45  *
  46  * > Hi, I'd like to use your scandir replacement function found here:
  47  * > http://www.iro.umontreal.ca/~pinard/libit/dist/scandir/ But, it does
  48  * > not indicate authorship or licensing terms in it.  Could you tell me
  49  * > who wrote this code, under what license you distribute it, and whether
  50  * > and under what terms I may further distribute it?
  51  *
  52  * Hello, Alan.  These are (somewhat) explained in UNSHAR.HDR found in the
  53  * same directory.  The routines have been written by Rick Saltz (I'm not
  54  * completely sure of the spelling) a long while ago.  I think that nowadays,
  55  * Rick is better known as the main author of the nice INN package.
  56  *
  57  **************************************************************************
  58  *
  59  * I spent a little time verifying this with Rick Salz.
  60  * The results are below:
  61  *
  62  **************************************************************************
  63  *
  64  * Date: Tue, 20 Sep 2005 21:52:09 -0400 (EDT)
  65  * From: Rich Salz <rsalz@datapower.com>
  66  * To: Alan Robertson <alanr@unix.sh>
  67  * Subject: Re: Verifying permissions/licenses/etc on some old code of yours -
  68  *  scandir.c
  69  * In-Reply-To: <433071CA.8000107@unix.sh>
  70  * Message-ID: <Pine.LNX.4.44L0.0509202151270.9198-100000@smtp.datapower.com>
  71  * Content-Type: TEXT/PLAIN; charset=US-ASCII
  72  *
  73  * yes, it's most definitely in the public domain.
  74  *
  75  * I'm glad you find it useful.  I'm surprised it hasn't been replaced by,
  76  * e.g,. something in GLibC.  Ii'm impressed you tracked me down.
  77  *
  78  *      /r$
  79  *
  80  * --
  81  * Rich Salz                  Chief Security Architect
  82  * DataPower Technology       http://www.datapower.com
  83  * XS40 XML Security Gateway  http://www.datapower.com/products/xs40.html
  84  * ---------------------------------------------------------------------->
  85  * Subject:     scandir, ftw REDUX
  86  * Date:        1 Jan 88 00:47:01 GMT
  87  * From:        rsalz@pebbles.bbn.com
  88  * Newsgroups:  comp.sources.misc
  89  *
  90  *
  91  * Forget my previous message -- I just decided for completeness's sake to
  92  * implement the SysV ftw(3) routine, too.
  93  *
  94  * To repeat, these are public-domain implementations of the SystemV ftw()
  95  * routine, the BSD scandir() and alphasort() routines, and documentation for
  96  * same.  The FTW manpage could be more readable, but so it goes.
  97  *
  98  * Anyhow, feel free to post these, and incorporate them into your existing
  99  * packages.  I have readdir() routiens for MSDOS and the Amiga if anyone
 100  *  wants them, and should have them for VMS by the end of January; let me
 101  *  know if you want copies.
 102  *
 103  *                        Yours in filesystems,
 104  *                                /r$
 105  *
 106  *                                Anyhow, feel free to post
 107  * ----------------------------------------------------------------------<
 108  *
 109  */
 110
 111 #include "routines.h"
 112 #include "routines_p.h"
 113
 114 #if defined (HAVE_SCANDIR) && defined (HAVE_DIRENT_H)
 115 #include <dirent.h>
 116 #elif defined (HAVE_DIRENT_H) || defined (_MSC_VER)
 117 # ifdef HAVE_DIRENT_H
 118 # include <dirent.h>
 119 # endif
 120 #define USE_SCANDIR_COMPARE_STRUCT_DIRENT
 121
 122 #include <sys/types.h>
 123
 124 #include <stdlib.h>
 125 #include <stddef.h>
 126 #include <string.h>
 127
 128 #ifndef NULL
 129 #  define NULL ((void *) 0)
 130 #endif
 131
 132 /* Initial guess at directory allocated.  */
 133 #define INITIAL_ALLOCATION 20
 134
 135 int
 136 scandir(const char *directory_name,
 137         struct dirent ***array_pointer, int (*select_function) (const struct dirent *),
 138 #ifdef USE_SCANDIR_COMPARE_STRUCT_DIRENT
 139         /* This is what the linux man page says */
 140         int (*compare_function) (const struct dirent **, const struct dirent **)
 141 #else
 142         /* This is what the linux header file says ... */
 143         int (*compare_function) (const void *, const void *)
 144 #endif
 145     )
 146 {
 147     DIR *directory;
 148     struct dirent **array;
 149     struct dirent *entry;
 150     struct dirent *copy;
 151     int allocated = INITIAL_ALLOCATION;
 152     int counter = 0;
 153
 154     /* Get initial list space and open directory.  */
 155
 156     if (directory = opendir(directory_name), directory == NULL)
 157         return -1;
 158
 159     if (array = (struct dirent **)eMalloc(allocated * sizeof(struct dirent *)), array == NULL)
 160         return -1;
 161
 162     /* Read entries in the directory.  */
 163
 164     while (entry = readdir(directory), entry)
 165         if (select_function == NULL || (*select_function) (entry)) {
 166             /* User wants them all, or he wants this one.  Copy the entry.  */
 167
 168             /*
 169              * On some OSes the declaration of "entry->d_name" is a minimal-length
 170              * placeholder.  Example: Solaris:
 171              *      /usr/include/sys/dirent.h:
 172              *              "char d_name[1];"
 173              *      man page "dirent(3)":
 174              *              The field d_name is the beginning of the character array
 175              *              giving the name of the directory entry. This name is
 176              *              null terminated and may have at most MAXNAMLEN chars.
 177              * So our malloc length may need to be increased accordingly.
 178              *      sizeof(entry->d_name): space (possibly minimal) in struct.
 179              *      strlen(entry->d_name): actual length of the entry.
 180              *
 181              *                      John Kavadias <john_kavadias@hotmail.com>
 182              *                      David Lee <t.d.lee@durham.ac.uk>
 183              */
 184             int namelength = strlen(entry->d_name) + 1; /* length with NULL */
 185             int extra = 0;
 186
 187             if (sizeof(entry->d_name) <= namelength) {
 188                 /* allocated space <= required space */
 189                 extra += namelength - sizeof(entry->d_name);
 190             }
 191
 192             if (copy = (struct dirent *)eMalloc(sizeof(struct dirent) + extra), copy == NULL) {
 193                 closedir(directory);
 194                 eFree(array);
 195                 return -1;
 196             }
 197             copy->d_ino = entry->d_ino;
 198             copy->d_reclen = entry->d_reclen;
 199             strcpy(copy->d_name, entry->d_name);
 200
 201             /* Save the copy.  */
 202
 203             if (counter + 1 == allocated) {
 204                 allocated <<= 1;
 205                 array = (struct dirent **)
 206                     eRealloc((char *)array, allocated * sizeof(struct dirent *));
 207                 if (array == NULL) {
 208                     closedir(directory);
 209                     eFree(array);
 210                     eFree(copy);
 211                     return -1;
 212                 }
 213             }
 214             array[counter++] = copy;
 215         }
 216
 217     /* Close things off.  */
 218
 219     array[counter] = NULL;
 220     *array_pointer = array;
 221     closedir(directory);
 222
 223     /* Sort?  */
 224
 225     if (counter > 1 && compare_function)
 226         qsort((char *)array, counter, sizeof(struct dirent *)
 227               , (int (*)(const void *, const void *))(compare_function));
 228
 229     return counter;
 230 }
 231 #endif
 232
 233 #if defined (HAVE_DIRENT_H) || defined (_MSC_VER)
 234 int scanDirectory (const char *directory_name,
 235                                    struct dirent ***array_pointer, int (*select_function) (const struct dirent *),
 236                                    int (*compare_function) (const struct dirent **, const struct dirent **))
 237 {
 238         return scandir (directory_name, array_pointer, select_function, compare_function);
 239 }
 240 #endif