packages: hardlink/hardlink.1 (NEW), hardlink/hardlink.c (NEW), hardlink/ha...

baggins baggins at pld-linux.org
Wed Mar 21 14:03:10 CET 2012


Author: baggins                      Date: Wed Mar 21 13:03:10 2012 GMT
Module: packages                      Tag: HEAD
---- Log message:
- new

---- Files affected:
packages/hardlink:
   hardlink.1 (NONE -> 1.1)  (NEW), hardlink.c (NONE -> 1.1)  (NEW), hardlink.spec (NONE -> 1.1)  (NEW)

---- Diffs:

================================================================
Index: packages/hardlink/hardlink.1
diff -u /dev/null packages/hardlink/hardlink.1:1.1
--- /dev/null	Wed Mar 21 14:03:10 2012
+++ packages/hardlink/hardlink.1	Wed Mar 21 14:03:05 2012
@@ -0,0 +1,48 @@
+.TH "hardlink" "1"
+.SH "NAME"
+hardlink \- Consolidate duplicate files via hardlinks
+.SH "SYNOPSIS"
+.PP
+\fBhardlink\fP [\fB-c\fP] [\fB-n\fP] [\fB-v\fP] [\fB-vv\fP] [\fB-h\fP] directory1 [ directory2 ... ]
+.SH "DESCRIPTION"
+.PP
+This manual page documents \fBhardlink\fP, a
+program which consolidates duplicate files in one or more directories
+using hardlinks.
+.PP
+\fBhardlink\fP traverses one
+or more directories searching for duplicate files.  When it finds duplicate
+files, it uses one of them as the master.  It then removes all other
+duplicates and places a hardlink for each one pointing to the master file.
+This allows for conservation of disk space where multiple directories
+on a single filesystem contain many duplicate files.
+.PP
+Since hard links can only span a single filesystem, \fBhardlink\fP
+is only useful when all directories specified are on the same filesystem.
+.SH "OPTIONS"
+.PP
+.IP "\fB-c\fP" 10
+Compare only the contents of the files being considered for consolidation.
+Disregards permission, ownership and other differences.
+.IP "\fB-n\fP" 10
+Do not perform the consolidation; only print what would be changed.
+.IP "\fB-v\fP" 10
+Print summary after hardlinking.
+.IP "\fB-vv\fP" 10
+Print every hardlinked file and bytes saved. Also print summary after hardlinking.
+.IP "\fB-h\fP" 10
+Show help.
+.SH "AUTHOR"
+.PP
+\fBhardlink\fP was written by Jakub Jelinek <jakub at redhat.com>.
+.PP
+Man page written by Brian Long.
+.PP
+Man page updated by Jindrich Novy <jnovy at redhat.com>
+.SH "BUGS"
+.PP
+\fBhardlink\fP assumes that its target directory trees do not change from under
+it.  If a directory tree does change, this may result in \fBhardlink\fP
+accessing files and/or directories outside of the intended directory tree.
+Thus, you must avoid running \fBhardlink\fP on potentially changing directory
+trees, and especially on directory trees under control of another user.

================================================================
Index: packages/hardlink/hardlink.c
diff -u /dev/null packages/hardlink/hardlink.c:1.1
--- /dev/null	Wed Mar 21 14:03:10 2012
+++ packages/hardlink/hardlink.c	Wed Mar 21 14:03:05 2012
@@ -0,0 +1,382 @@
+/* Copyright (C) 2001 Red Hat, Inc.
+
+   Written by Jakub Jelinek <jakub at redhat.com>.
+
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+
+   You should have received a copy of the GNU General Public
+   License along with this program; see the file COPYING.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+/*  Changes by Rémy Card to use constants and add option -n.  */
+/*  Changes by Jindrich Novy to add option -h, replace mmap(2), fix overflows */
+
+#define _GNU_SOURCE
+#include <sys/types.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+#include <string.h>
+#include <dirent.h>
+#include <fcntl.h>
+
+#define NHASH	(1<<17)	/* Must be a power of 2! */
+#define NIOBUF	(1<<12)
+#define NAMELEN	4096
+#define NBUF	64
+
+struct _f;
+typedef struct _h {
+  struct _h *next;
+  struct _f *chain;
+  off_t size;
+  time_t mtime;
+} h;
+
+typedef struct _d {
+  struct _d *next;
+  char name[0];
+} d;
+
+d *dirs;
+
+h *hps[NHASH];
+
+int no_link = 0;
+int verbose = 0;
+int content_only = 0;
+
+typedef struct _f {
+  struct _f *next;
+  ino_t ino;
+  dev_t dev;
+  unsigned int cksum;
+  char name[0];
+} f;
+
+inline unsigned int hash(off_t size, time_t mtime)
+{
+  return (size ^ mtime) & (NHASH - 1);
+}
+
+inline int stcmp(struct stat *st1, struct stat *st2, int content_only)
+{
+  if (content_only)
+    return st1->st_size != st2->st_size;
+  return st1->st_mode != st2->st_mode || st1->st_uid != st2->st_uid ||
+         st1->st_gid != st2->st_gid || st1->st_size != st2->st_size ||
+         st1->st_mtime != st2->st_mtime;
+}
+
+long long ndirs, nobjects, nregfiles, ncomp, nlinks, nsaved;
+
+void doexit(int i)
+{
+  if (verbose) {
+    fprintf(stderr, "\n\n");
+    fprintf(stderr, "Directories %lld\n", ndirs);
+    fprintf(stderr, "Objects %lld\n", nobjects);
+    fprintf(stderr, "IFREG %lld\n", nregfiles);
+    fprintf(stderr, "Comparisons %lld\n", ncomp);
+    fprintf(stderr, "%s %lld\n", (no_link ? "Would link" : "Linked"), nlinks);
+    fprintf(stderr, "%s %lld\n", (no_link ? "Would save" : "saved"), nsaved);
+  }
+  exit(i);
+}
+
+void usage(char *prog)
+{
+  fprintf (stderr, "Usage: %s [-cnvh] directories...\n", prog);
+  fprintf (stderr, "  -c    When finding candidates for linking, compare only file contents.\n");
+  fprintf (stderr, "  -n    Don't actually link anything, just report what would be done.\n");
+  fprintf (stderr, "  -v    Print summary after hardlinking.\n");
+  fprintf (stderr, "  -vv   Print every hardlinked file and bytes saved + summary.\n");
+  fprintf (stderr, "  -h    Show help.\n");
+  exit(255);
+}
+
+unsigned int buf[NBUF];
+char iobuf1[NIOBUF], iobuf2[NIOBUF];
+
+inline size_t add2(size_t a, size_t b)
+{
+  size_t sum = a + b;
+  if (sum < a) {
+    fprintf(stderr, "\nInteger overflow\n");
+    doexit(5);
+  }
+  return sum;
+}
+
+inline size_t add3(size_t a, size_t b, size_t c)
+{
+  return add2(add2(a, b), c);
+}
+
+typedef struct {
+  char *buf;
+  size_t alloc;
+} dynstr;
+
+void growstr(dynstr *str, size_t newlen)
+{
+  if (newlen < str->alloc)
+    return;
+  str->buf = realloc(str->buf, str->alloc = add2(newlen, 1));
+  if (!str->buf) {
+    fprintf(stderr, "\nOut of memory 4\n");
+    doexit(4);
+  }
+}
+
+void rf (const char *name)
+{
+  struct stat st, st2, st3;
+  const size_t namelen = strlen(name);
+  nobjects++;
+  if (lstat (name, &st))
+    return;
+  if (S_ISDIR (st.st_mode)) {
+    d * dp = malloc(add3(sizeof(d), namelen, 1));
+    if (!dp) {
+      fprintf(stderr, "\nOut of memory 3\n");
+      doexit(3);
+    }
+    memcpy(dp->name, name, namelen + 1);
+    dp->next = dirs;
+    dirs = dp;
+  } else if (S_ISREG (st.st_mode)) {
+    int fd, i;
+    f * fp, * fp2;
+    h * hp;
+    const char *n1, *n2;
+    int cksumsize = sizeof(buf);
+    unsigned int cksum;
+    time_t mtime = content_only ? 0 : st.st_mtime;
+    unsigned int hsh = hash (st.st_size, mtime);
+    off_t fsize;
+    nregfiles++;
+    if (verbose > 1)
+      fprintf(stderr, "  %s", name);
+    fd = open (name, O_RDONLY);
+    if (fd < 0) return;
+    if (st.st_size < sizeof(buf)) {
+      cksumsize = st.st_size;
+      memset (((char *)buf) + cksumsize, 0, (sizeof(buf) - cksumsize) % sizeof(buf[0]));
+    }
+    if (read (fd, buf, cksumsize) != cksumsize) {
+      close(fd);
+      if (verbose > 1 && namelen <= NAMELEN)
+        fprintf(stderr, "\r%*s\r", (int)(namelen + 2), "");
+      return;
+    }
+    cksumsize = (cksumsize + sizeof(buf[0]) - 1) / sizeof(buf[0]);
+    for (i = 0, cksum = 0; i < cksumsize; i++) {
+      if (cksum + buf[i] < cksum)
+        cksum += buf[i] + 1;
+      else
+        cksum += buf[i];
+    }
+    for (hp = hps[hsh]; hp; hp = hp->next)
+      if (hp->size == st.st_size && hp->mtime == mtime)
+        break;
+    if (!hp) {
+      hp = malloc(sizeof(h));
+      if (!hp) {
+        fprintf(stderr, "\nOut of memory 1\n");
+        doexit(1);
+      }
+      hp->size = st.st_size;
+      hp->mtime = mtime;
+      hp->chain = NULL;
+      hp->next = hps[hsh];
+      hps[hsh] = hp;
+    }
+    for (fp = hp->chain; fp; fp = fp->next)
+      if (fp->cksum == cksum)
+        break;
+    for (fp2 = fp; fp2 && fp2->cksum == cksum; fp2 = fp2->next)
+      if (fp2->ino == st.st_ino && fp2->dev == st.st_dev) {
+        close(fd);
+        if (verbose > 1 && namelen <= NAMELEN)
+          fprintf(stderr, "\r%*s\r", (int)(namelen + 2), "");
+        return;
+      }
+    for (fp2 = fp; fp2 && fp2->cksum == cksum; fp2 = fp2->next)
+      if (!lstat (fp2->name, &st2) && S_ISREG (st2.st_mode) &&
+          !stcmp (&st, &st2, content_only) &&
+          st2.st_ino != st.st_ino &&
+          st2.st_dev == st.st_dev) {
+        int fd2 = open (fp2->name, O_RDONLY);
+        if (fd2 < 0) continue;
+        if (fstat (fd2, &st2) || !S_ISREG (st2.st_mode) || st2.st_size == 0) {
+          close (fd2);
+          continue;
+        }
+        ncomp++;
+	lseek(fd, 0, SEEK_SET);
+	for (fsize = st.st_size; fsize > 0; fsize -= NIOBUF) {
+	  off_t rsize = fsize >= NIOBUF ? NIOBUF : fsize;
+	  if (read (fd, iobuf1, rsize) != rsize || read (fd2, iobuf2, rsize) != rsize) {
+	    close(fd);
+	    close(fd2);
+	    fprintf(stderr, "\nReading error\n");
+	    return;
+	  }
+	  if (memcmp (iobuf1, iobuf2, rsize)) break;
+	}
+	close(fd2);
+	if (fsize > 0) continue;
+        if (lstat (name, &st3)) {
+          fprintf(stderr, "\nCould not stat %s again\n", name);
+          close(fd);
+          return;
+        }
+        st3.st_atime = st.st_atime;
+        if (stcmp (&st, &st3, 0)) {
+          fprintf(stderr, "\nFile %s changed underneath us\n", name);
+          close(fd);
+          return;
+        }
+        n1 = fp2->name;
+        n2 = name;
+        if (!no_link) {
+          const char *suffix = ".$$$___cleanit___$$$";
+          const size_t suffixlen = strlen(suffix);
+          size_t n2len = strlen(n2);
+          dynstr nam2 = {NULL, 0};
+          growstr(&nam2, add2(n2len, suffixlen));
+          memcpy(nam2.buf, n2, n2len);
+          memcpy(&nam2.buf[n2len], suffix, suffixlen + 1);
+          if (rename (n2, nam2.buf)) {
+            fprintf(stderr, "\nFailed to rename %s to %s\n", n2, nam2.buf);
+            free(nam2.buf);
+            continue;
+          }
+          if (link (n1, n2)) {
+            fprintf(stderr, "\nFailed to hardlink %s to %s\n", n1, n2);
+            if (rename (nam2.buf, n2)) {
+              fprintf(stderr, "\nBad bad - failed to rename back %s to %s\n", nam2.buf, n2);
+            }
+            close(fd);
+            free(nam2.buf);
+            return;
+          }
+          unlink (nam2.buf);
+          free(nam2.buf);
+        }
+        nlinks++;
+        if (st3.st_nlink > 1) {
+	  /* We actually did not save anything this time, since the link second argument
+	     had some other links as well.  */
+          if (verbose > 1)
+            fprintf(stderr, "\r%*s\r%s %s to %s\n", (int)(((namelen > NAMELEN) ? 0 : namelen) + 2), "", (no_link ? "Would link" : "Linked"), n1, n2);
+        } else {
+          nsaved+=((st.st_size+4095)/4096)*4096;
+          if (verbose > 1)
+            fprintf(stderr, "\r%*s\r%s %s to %s, %s %ld\n", (int)(((namelen > NAMELEN) ? 0 : namelen) + 2), "", (no_link ? "Would link" : "Linked"), n1, n2, (no_link ? "would save" : "saved"), st.st_size);
+	}
+        close(fd);
+        return;
+      }
+    fp2 = malloc(add3(sizeof(f), namelen, 1));
+    if (!fp2) {
+      fprintf(stderr, "\nOut of memory 2\n");
+      doexit(2);
+    }
+    close(fd);
+    fp2->ino = st.st_ino;
+    fp2->dev = st.st_dev;
+    fp2->cksum = cksum;
+    memcpy(fp2->name, name, namelen + 1);
+    if (fp) {
+      fp2->next = fp->next;
+      fp->next = fp2;
+    } else {
+      fp2->next = hp->chain;
+      hp->chain = fp2;
+    }
+    if (verbose > 1 && namelen <= NAMELEN)
+      fprintf(stderr, "\r%*s\r", (int)(namelen + 2), "");
+    return;
+  }
+}
+
+int main(int argc, char **argv)
+{
+  int ch;
+  int i;
+  dynstr nam1 = {NULL, 0};
+  while ((ch = getopt (argc, argv, "cnvh")) != -1) {
+    switch (ch) {
+    case 'n':
+      no_link++;
+      break;
+    case 'v':
+      verbose++;
+      break;
+    case 'c':
+      content_only++;
+      break;
+    case 'h':
+    default:
+      usage(argv[0]);
+    }
+  }
+  if (optind >= argc)
+    usage(argv[0]);
+  for (i = optind; i < argc; i++)
+    rf(argv[i]);
+  while (dirs) {
+    DIR *dh;
+    struct dirent *di;
+    d * dp = dirs;
+    size_t nam1baselen = strlen(dp->name);
+    dirs = dp->next;
+    growstr(&nam1, add2(nam1baselen, 1));
+    memcpy(nam1.buf, dp->name, nam1baselen);
+    free (dp);
+    nam1.buf[nam1baselen++] = '/';
+    nam1.buf[nam1baselen] = 0;
+    dh = opendir (nam1.buf);
+    if (dh == NULL)
+      continue;
+    ndirs++;
+    while ((di = readdir (dh)) != NULL) {
+      if (!di->d_name[0])
+        continue;
+      if (di->d_name[0] == '.') {
+        char *q;
+        if (!di->d_name[1] || !strcmp (di->d_name, "..") || !strncmp (di->d_name, ".in.", 4))
+          continue;
+        q = strrchr (di->d_name, '.');
+        if (q && strlen (q) == 7 && q != di->d_name) {
+          nam1.buf[nam1baselen] = 0;
+          if (verbose)
+            fprintf(stderr, "Skipping %s%s\n", nam1.buf, di->d_name);
+          continue;
+        }
+      }
+      {
+        size_t subdirlen;
+        growstr(&nam1, add2(nam1baselen, subdirlen = strlen(di->d_name)));
+        memcpy(&nam1.buf[nam1baselen], di->d_name, add2(subdirlen, 1));
+      }
+      rf(nam1.buf);
+    }
+    closedir(dh);
+  }
+  doexit(0);
+  return 0;
+}

================================================================
Index: packages/hardlink/hardlink.spec
diff -u /dev/null packages/hardlink/hardlink.spec:1.1
--- /dev/null	Wed Mar 21 14:03:10 2012
+++ packages/hardlink/hardlink.spec	Wed Mar 21 14:03:05 2012
@@ -0,0 +1,48 @@
+# $Revision$, $Date$
+Summary:	Create a tree of hardlinks
+Name:		hardlink
+Version:	1.0
+Release:	1
+License:	GPL+
+Group:		Base
+URL:		http://pkgs.fedoraproject.org/gitweb/?p=hardlink.git
+Source0:	%{name}.c
+Source1:	%{name}.1
+BuildRoot:	%{tmpdir}/%{name}-%{version}-root-%(id -u -n)
+
+%description
+hardlink is used to create a tree of hard links. It's used by kernel
+installation to dramatically reduce the amount of diskspace used by
+each kernel package installed.
+
+%prep
+%setup -q -c -T
+install -pm 644 %{SOURCE0} hardlink.c
+
+%build
+%{__cc} %{rpmcflags} hardlink.c -o hardlink
+
+%install
+rm -rf $RPM_BUILD_ROOT
+install -d $RPM_BUILD_ROOT{%{_mandir}/man1,%{_sbindir}}
+
+install hardlink $RPM_BUILD_ROOT%{_sbindir}/hardlink
+install -p %{SOURCE1} $RPM_BUILD_ROOT%{_mandir}/man1/hardlink.1
+
+%clean
+rm -rf $RPM_BUILD_ROOT
+
+%files
+%defattr(644,root,root,755)
+%attr(755,root,root) %{_sbindir}/hardlink
+%{_mandir}/man1/hardlink.1*
+
+%define date	%(echo `LC_ALL="C" date +"%a %b %d %Y"`)
+%changelog
+* %{date} PLD Team <feedback at pld-linux.org>
+All persons listed below can be reached at <cvs_login>@pld-linux.org
+
+$Log$
+Revision 1.1  2012/03/21 13:03:05  baggins
+- new
+
================================================================


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