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-rw-r--r--misc-utils/hardlink.c531
1 files changed, 531 insertions, 0 deletions
diff --git a/misc-utils/hardlink.c b/misc-utils/hardlink.c
new file mode 100644
index 0000000..2711b2a
--- /dev/null
+++ b/misc-utils/hardlink.c
@@ -0,0 +1,531 @@
+/*
+ * hardlink - consolidate duplicate files via hardlinks
+ *
+ * Copyright (C) 2018 Red Hat, Inc. All rights reserved.
+ * Written by Jakub Jelinek <jakub@redhat.com>
+ *
+ * Copyright (C) 2019 Karel Zak <kzak@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 would 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; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+#include <sys/types.h>
+#include <stdlib.h>
+#include <getopt.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+#include <string.h>
+#include <dirent.h>
+#include <fcntl.h>
+#include <errno.h>
+#ifdef HAVE_PCRE
+# define PCRE2_CODE_UNIT_WIDTH 8
+# include <pcre2.h>
+#endif
+
+#include "c.h"
+#include "xalloc.h"
+#include "nls.h"
+#include "closestream.h"
+
+#define NHASH (1<<17) /* Must be a power of 2! */
+#define NBUF 64
+
+struct hardlink_file;
+
+struct hardlink_hash {
+ struct hardlink_hash *next;
+ struct hardlink_file *chain;
+ off_t size;
+ time_t mtime;
+};
+
+struct hardlink_dir {
+ struct hardlink_dir *next;
+ char name[];
+};
+
+struct hardlink_file {
+ struct hardlink_file *next;
+ ino_t ino;
+ dev_t dev;
+ unsigned int cksum;
+ char name[];
+};
+
+struct hardlink_dynstr {
+ char *buf;
+ size_t alloc;
+};
+
+struct hardlink_ctl {
+ struct hardlink_dir *dirs;
+ struct hardlink_hash *hps[NHASH];
+ char iobuf1[BUFSIZ];
+ char iobuf2[BUFSIZ];
+ /* summary counters */
+ unsigned long long ndirs;
+ unsigned long long nobjects;
+ unsigned long long nregfiles;
+ unsigned long long ncomp;
+ unsigned long long nlinks;
+ unsigned long long nsaved;
+ /* current device */
+ dev_t dev;
+ /* flags */
+ unsigned int verbose;
+ unsigned int
+ no_link:1,
+ content_only:1,
+ force:1;
+};
+/* ctl is in global scope due use in atexit() */
+struct hardlink_ctl global_ctl;
+
+__attribute__ ((always_inline))
+static inline unsigned int hash(off_t size, time_t mtime)
+{
+ return (size ^ mtime) & (NHASH - 1);
+}
+
+__attribute__ ((always_inline))
+static inline int stcmp(struct stat *st1, struct stat *st2, int content_scope)
+{
+ if (content_scope)
+ 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;
+}
+
+static void print_summary(void)
+{
+ struct hardlink_ctl const *const ctl = &global_ctl;
+
+ if (!ctl->verbose)
+ return;
+
+ if (ctl->verbose > 1 && ctl->nlinks)
+ fputc('\n', stdout);
+
+ printf(_("Directories: %9lld\n"), ctl->ndirs);
+ printf(_("Objects: %9lld\n"), ctl->nobjects);
+ printf(_("Regular files: %9lld\n"), ctl->nregfiles);
+ printf(_("Comparisons: %9lld\n"), ctl->ncomp);
+ printf( "%s%9lld\n", (ctl->no_link ?
+ _("Would link: ") :
+ _("Linked: ")), ctl->nlinks);
+ printf( "%s %9lld\n", (ctl->no_link ?
+ _("Would save: ") :
+ _("Saved: ")), ctl->nsaved);
+}
+
+static void __attribute__((__noreturn__)) usage(void)
+{
+ fputs(USAGE_HEADER, stdout);
+ printf(_(" %s [options] directory...\n"), program_invocation_short_name);
+
+ fputs(USAGE_SEPARATOR, stdout);
+ puts(_("Consolidate duplicate files using hardlinks."));
+
+ fputs(USAGE_OPTIONS, stdout);
+ puts(_(" -c, --content compare only contents, ignore permission, etc."));
+ puts(_(" -n, --dry-run don't actually link anything"));
+ puts(_(" -v, --verbose print summary after hardlinking"));
+ puts(_(" -vv print every hardlinked file and summary"));
+ puts(_(" -f, --force force hardlinking across filesystems"));
+ puts(_(" -x, --exclude <regex> exclude files matching pattern"));
+
+ fputs(USAGE_SEPARATOR, stdout);
+ printf(USAGE_HELP_OPTIONS(16)); /* char offset to align option descriptions */
+ printf(USAGE_MAN_TAIL("hardlink(1)"));
+ exit(EXIT_SUCCESS);
+}
+
+__attribute__ ((always_inline))
+static inline size_t add2(size_t a, size_t b)
+{
+ size_t sum = a + b;
+
+ if (sum < a)
+ errx(EXIT_FAILURE, _("integer overflow"));
+ return sum;
+}
+
+__attribute__ ((always_inline))
+static inline size_t add3(size_t a, size_t b, size_t c)
+{
+ return add2(add2(a, b), c);
+}
+
+static void growstr(struct hardlink_dynstr *str, size_t newlen)
+{
+ if (newlen < str->alloc)
+ return;
+ str->buf = xrealloc(str->buf, str->alloc = add2(newlen, 1));
+}
+
+static void process_path(struct hardlink_ctl *ctl, const char *name)
+{
+ struct stat st, st2, st3;
+ const size_t namelen = strlen(name);
+
+ ctl->nobjects++;
+ if (lstat(name, &st))
+ return;
+
+ if (st.st_dev != ctl->dev && !ctl->force) {
+ if (ctl->dev)
+ errx(EXIT_FAILURE,
+ _("%s is on different filesystem than the rest "
+ "(use -f option to override)."), name);
+ ctl->dev = st.st_dev;
+ }
+ if (S_ISDIR(st.st_mode)) {
+ struct hardlink_dir *dp = xmalloc(add3(sizeof(*dp), namelen, 1));
+ memcpy(dp->name, name, namelen + 1);
+ dp->next = ctl->dirs;
+ ctl->dirs = dp;
+
+ } else if (S_ISREG(st.st_mode)) {
+ int fd, i;
+ struct hardlink_file *fp, *fp2;
+ struct hardlink_hash *hp;
+ const char *n1, *n2;
+ unsigned int buf[NBUF];
+ int cksumsize = sizeof(buf);
+ unsigned int cksum;
+ time_t mtime = ctl->content_only ? 0 : st.st_mtime;
+ unsigned int hsh = hash(st.st_size, mtime);
+ off_t fsize;
+
+ ctl->nregfiles++;
+ if (ctl->verbose > 1)
+ printf("%s\n", name);
+
+ fd = open(name, O_RDONLY);
+ if (fd < 0)
+ return;
+
+ if ((size_t)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);
+ 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 = ctl->hps[hsh]; hp; hp = hp->next) {
+ if (hp->size == st.st_size && hp->mtime == mtime)
+ break;
+ }
+ if (!hp) {
+ hp = xmalloc(sizeof(*hp));
+ hp->size = st.st_size;
+ hp->mtime = mtime;
+ hp->chain = NULL;
+ hp->next = ctl->hps[hsh];
+ ctl->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);
+ return;
+ }
+ }
+ for (fp2 = fp; fp2 && fp2->cksum == cksum; fp2 = fp2->next) {
+
+ if (!lstat(fp2->name, &st2) && S_ISREG(st2.st_mode) &&
+ !stcmp(&st, &st2, ctl->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;
+ }
+ ctl->ncomp++;
+ lseek(fd, 0, SEEK_SET);
+
+ for (fsize = st.st_size; fsize > 0;
+ fsize -= (off_t)sizeof(ctl->iobuf1)) {
+ ssize_t xsz;
+ ssize_t rsize = fsize > (ssize_t) sizeof(ctl->iobuf1) ?
+ (ssize_t) sizeof(ctl->iobuf1) : fsize;
+
+ if ((xsz = read(fd, ctl->iobuf1, rsize)) != rsize)
+ warn(_("cannot read %s"), name);
+ else if ((xsz = read(fd2, ctl->iobuf2, rsize)) != rsize)
+ warn(_("cannot read %s"), fp2->name);
+
+ if (xsz != rsize) {
+ close(fd);
+ close(fd2);
+ return;
+ }
+ if (memcmp(ctl->iobuf1, ctl->iobuf2, rsize) != 0)
+ break;
+ }
+ close(fd2);
+ if (fsize > 0)
+ continue;
+ if (lstat(name, &st3)) {
+ warn(_("cannot stat %s"), name);
+ close(fd);
+ return;
+ }
+ st3.st_atime = st.st_atime;
+ if (stcmp(&st, &st3, 0)) {
+ warnx(_("file %s changed underneath us"), name);
+ close(fd);
+ return;
+ }
+ n1 = fp2->name;
+ n2 = name;
+
+ if (!ctl->no_link) {
+ const char *suffix =
+ ".$$$___cleanit___$$$";
+ const size_t suffixlen = strlen(suffix);
+ size_t n2len = strlen(n2);
+ struct hardlink_dynstr nam2 = { NULL, 0 };
+
+ growstr(&nam2, add2(n2len, suffixlen));
+ memcpy(nam2.buf, n2, n2len);
+ memcpy(&nam2.buf[n2len], suffix,
+ suffixlen + 1);
+ /* First create a temporary link to n1 under a new name */
+ if (link(n1, nam2.buf)) {
+ warn(_("failed to hardlink %s to %s (create temporary link as %s failed)"),
+ n1, n2, nam2.buf);
+ free(nam2.buf);
+ continue;
+ }
+ /* Then rename into place over the existing n2 */
+ if (rename(nam2.buf, n2)) {
+ warn(_("failed to hardlink %s to %s (rename temporary link to %s failed)"),
+ n1, n2, n2);
+ /* Something went wrong, try to remove the now redundant temporary link */
+ if (unlink(nam2.buf))
+ warn(_("failed to remove temporary link %s"), nam2.buf);
+ free(nam2.buf);
+ continue;
+ }
+ free(nam2.buf);
+ }
+ ctl->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 (ctl->verbose > 1)
+ printf(_(" %s %s to %s\n"),
+ (ctl->no_link ? _("Would link") : _("Linked")),
+ n1, n2);
+ } else {
+ ctl->nsaved += ((st.st_size + 4095) / 4096) * 4096;
+ if (ctl->verbose > 1)
+ printf(_(" %s %s to %s, %s %jd\n"),
+ (ctl->no_link ? _("Would link") : _("Linked")),
+ n1, n2,
+ (ctl->no_link ? _("would save") : _("saved")),
+ (intmax_t)st.st_size);
+ }
+ close(fd);
+ return;
+ }
+ }
+ fp2 = xmalloc(add3(sizeof(*fp2), namelen, 1));
+ 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;
+ }
+ return;
+ }
+}
+
+int main(int argc, char **argv)
+{
+ int ch;
+ int i;
+#ifdef HAVE_PCRE
+ int errornumber;
+ PCRE2_SIZE erroroffset;
+ pcre2_code *re = NULL;
+ PCRE2_SPTR exclude_pattern = NULL;
+ pcre2_match_data *match_data = NULL;
+#endif
+ struct hardlink_dynstr nam1 = { NULL, 0 };
+ struct hardlink_ctl *ctl = &global_ctl;
+
+ static const struct option longopts[] = {
+ { "content", no_argument, NULL, 'c' },
+ { "dry-run", no_argument, NULL, 'n' },
+ { "exclude", required_argument, NULL, 'x' },
+ { "force", no_argument, NULL, 'f' },
+ { "help", no_argument, NULL, 'h' },
+ { "verbose", no_argument, NULL, 'v' },
+ { "version", no_argument, NULL, 'V' },
+ { NULL, 0, NULL, 0 },
+ };
+
+ setlocale(LC_ALL, "");
+ bindtextdomain(PACKAGE, LOCALEDIR);
+ textdomain(PACKAGE);
+ close_stdout_atexit();
+
+ while ((ch = getopt_long(argc, argv, "cnvfx:Vh", longopts, NULL)) != -1) {
+ switch (ch) {
+ case 'n':
+ ctl->no_link = 1;
+ break;
+ case 'v':
+ ctl->verbose++;
+ break;
+ case 'c':
+ ctl->content_only = 1;
+ break;
+ case 'f':
+ ctl->force = 1;
+ break;
+ case 'x':
+#ifdef HAVE_PCRE
+ exclude_pattern = (PCRE2_SPTR) optarg;
+#else
+ errx(EXIT_FAILURE,
+ _("option --exclude not supported (built without pcre2)"));
+#endif
+ break;
+ case 'V':
+ print_version(EXIT_SUCCESS);
+ case 'h':
+ usage();
+ default:
+ errtryhelp(EXIT_FAILURE);
+ }
+ }
+
+ if (optind == argc) {
+ warnx(_("no directory specified"));
+ errtryhelp(EXIT_FAILURE);
+ }
+
+#ifdef HAVE_PCRE
+ if (exclude_pattern) {
+ re = pcre2_compile(exclude_pattern, /* the pattern */
+ PCRE2_ZERO_TERMINATED, /* indicates pattern is zero-terminate */
+ 0, /* default options */
+ &errornumber, &erroroffset, NULL); /* use default compile context */
+ if (!re) {
+ PCRE2_UCHAR buffer[256];
+ pcre2_get_error_message(errornumber, buffer,
+ sizeof(buffer));
+ errx(EXIT_FAILURE, _("pattern error at offset %d: %s"),
+ (int)erroroffset, buffer);
+ }
+ match_data = pcre2_match_data_create_from_pattern(re, NULL);
+ }
+#endif
+ atexit(print_summary);
+
+ for (i = optind; i < argc; i++)
+ process_path(ctl, argv[i]);
+
+ while (ctl->dirs) {
+ DIR *dh;
+ struct dirent *di;
+ struct hardlink_dir *dp = ctl->dirs;
+ size_t nam1baselen = strlen(dp->name);
+
+ ctl->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;
+ ctl->ndirs++;
+
+ while ((di = readdir(dh)) != NULL) {
+ if (!di->d_name[0])
+ continue;
+ if (di->d_name[0] == '.') {
+ if (!di->d_name[1] || !strcmp(di->d_name, ".."))
+ continue;
+ }
+#ifdef HAVE_PCRE
+ if (re && pcre2_match(re, /* compiled regex */
+ (PCRE2_SPTR) di->d_name, strlen(di->d_name), 0, /* start at offset 0 */
+ 0, /* default options */
+ match_data, /* block for storing the result */
+ NULL) /* use default match context */
+ >=0) {
+ if (ctl->verbose) {
+ nam1.buf[nam1baselen] = 0;
+ printf(_("Skipping %s%s\n"), nam1.buf, di->d_name);
+ }
+ continue;
+ }
+#endif
+ {
+ size_t subdirlen;
+ growstr(&nam1,
+ add2(nam1baselen, subdirlen =
+ strlen(di->d_name)));
+ memcpy(&nam1.buf[nam1baselen], di->d_name,
+ add2(subdirlen, 1));
+ }
+ process_path(ctl, nam1.buf);
+ }
+ closedir(dh);
+ }
+#ifdef HAVE_PCRE
+ pcre2_code_free(re);
+ pcre2_match_data_free(match_data);
+#endif
+ return 0;
+}
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