summaryrefslogtreecommitdiffstats
path: root/misc-utils/lslocks.c
diff options
context:
space:
mode:
Diffstat (limited to 'misc-utils/lslocks.c')
-rw-r--r--misc-utils/lslocks.c679
1 files changed, 679 insertions, 0 deletions
diff --git a/misc-utils/lslocks.c b/misc-utils/lslocks.c
new file mode 100644
index 0000000..caca13f
--- /dev/null
+++ b/misc-utils/lslocks.c
@@ -0,0 +1,679 @@
+/*
+ * lslocks(8) - list local system locks
+ *
+ * Copyright (C) 2012 Davidlohr Bueso <dave@gnu.org>
+ *
+ * Very generally based on lslk(8) by Victor A. Abell <abe@purdue.edu>
+ * Since it stopped being maintained over a decade ago, this
+ * program should be considered its replacement.
+ *
+ * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <getopt.h>
+#include <stdlib.h>
+#include <assert.h>
+#include <dirent.h>
+#include <unistd.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include <libmount.h>
+#include <libsmartcols.h>
+
+#include "pathnames.h"
+#include "canonicalize.h"
+#include "nls.h"
+#include "xalloc.h"
+#include "strutils.h"
+#include "c.h"
+#include "list.h"
+#include "closestream.h"
+#include "optutils.h"
+#include "procfs.h"
+
+/* column IDs */
+enum {
+ COL_SRC = 0,
+ COL_PID,
+ COL_TYPE,
+ COL_SIZE,
+ COL_INODE,
+ COL_MAJMIN,
+ COL_MODE,
+ COL_M,
+ COL_START,
+ COL_END,
+ COL_PATH,
+ COL_BLOCKER
+};
+
+/* column names */
+struct colinfo {
+ const char *name; /* header */
+ double whint; /* width hint (N < 1 is in percent of termwidth) */
+ int flags; /* SCOLS_FL_* */
+ const char *help;
+};
+
+/* columns descriptions */
+static struct colinfo infos[] = {
+ [COL_SRC] = { "COMMAND",15, 0, N_("command of the process holding the lock") },
+ [COL_PID] = { "PID", 5, SCOLS_FL_RIGHT, N_("PID of the process holding the lock") },
+ [COL_TYPE] = { "TYPE", 5, SCOLS_FL_RIGHT, N_("kind of lock") },
+ [COL_SIZE] = { "SIZE", 4, SCOLS_FL_RIGHT, N_("size of the lock") },
+ [COL_INODE] = { "INODE", 5, SCOLS_FL_RIGHT, N_("inode number") },
+ [COL_MAJMIN] = { "MAJ:MIN", 6, 0, N_("major:minor device number") },
+ [COL_MODE] = { "MODE", 5, 0, N_("lock access mode") },
+ [COL_M] = { "M", 1, 0, N_("mandatory state of the lock: 0 (none), 1 (set)")},
+ [COL_START] = { "START", 10, SCOLS_FL_RIGHT, N_("relative byte offset of the lock")},
+ [COL_END] = { "END", 10, SCOLS_FL_RIGHT, N_("ending offset of the lock")},
+ [COL_PATH] = { "PATH", 0, SCOLS_FL_TRUNC, N_("path of the locked file")},
+ [COL_BLOCKER] = { "BLOCKER", 0, SCOLS_FL_RIGHT, N_("PID of the process blocking the lock") }
+};
+
+static int columns[ARRAY_SIZE(infos) * 2];
+static size_t ncolumns;
+
+static pid_t pid = 0;
+
+static struct libmnt_table *tab; /* /proc/self/mountinfo */
+
+/* basic output flags */
+static int no_headings;
+static int no_inaccessible;
+static int raw;
+static int json;
+static int bytes;
+
+struct lock {
+ struct list_head locks;
+
+ char *cmdname;
+ pid_t pid;
+ char *path;
+ char *type;
+ char *mode;
+ off_t start;
+ off_t end;
+ ino_t inode;
+ dev_t dev;
+ unsigned int mandatory :1,
+ blocked :1;
+ uint64_t size;
+ int id;
+};
+
+static void rem_lock(struct lock *lock)
+{
+ if (!lock)
+ return;
+
+ free(lock->path);
+ free(lock->mode);
+ free(lock->cmdname);
+ free(lock->type);
+ list_del(&lock->locks);
+ free(lock);
+}
+
+static void disable_columns_truncate(void)
+{
+ size_t i;
+
+ for (i = 0; i < ARRAY_SIZE(infos); i++)
+ infos[i].flags &= ~SCOLS_FL_TRUNC;
+}
+
+/*
+ * Associate the device's mountpoint for a filename
+ */
+static char *get_fallback_filename(dev_t dev)
+{
+ struct libmnt_fs *fs;
+ char *res = NULL;
+
+ if (!tab) {
+ tab = mnt_new_table_from_file(_PATH_PROC_MOUNTINFO);
+ if (!tab)
+ return NULL;
+ }
+
+ fs = mnt_table_find_devno(tab, dev, MNT_ITER_BACKWARD);
+ if (!fs)
+ return NULL;
+
+ xasprintf(&res, "%s...", mnt_fs_get_target(fs));
+ return res;
+}
+
+/*
+ * Return the absolute path of a file from
+ * a given inode number (and its size)
+ */
+static char *get_filename_sz(ino_t inode, pid_t lock_pid, size_t *size)
+{
+ struct stat sb;
+ struct dirent *dp;
+ DIR *dirp;
+ size_t len;
+ int fd;
+ char path[PATH_MAX], sym[PATH_MAX], *ret = NULL;
+
+ *size = 0;
+ memset(path, 0, sizeof(path));
+ memset(sym, 0, sizeof(sym));
+
+ /*
+ * We know the pid so we don't have to
+ * iterate the *entire* filesystem searching
+ * for the damn file.
+ */
+ snprintf(path, sizeof(path), "/proc/%d/fd/", lock_pid);
+ if (!(dirp = opendir(path)))
+ return NULL;
+
+ if ((len = strlen(path)) >= (sizeof(path) - 2))
+ goto out;
+
+ if ((fd = dirfd(dirp)) < 0 )
+ goto out;
+
+ while ((dp = readdir(dirp))) {
+ if (!strcmp(dp->d_name, ".") ||
+ !strcmp(dp->d_name, ".."))
+ continue;
+
+ errno = 0;
+
+ /* care only for numerical descriptors */
+ if (!strtol(dp->d_name, (char **) NULL, 10) || errno)
+ continue;
+
+ if (!fstatat(fd, dp->d_name, &sb, 0)
+ && inode != sb.st_ino)
+ continue;
+
+ if ((len = readlinkat(fd, dp->d_name, sym, sizeof(sym) - 1)) < 1)
+ goto out;
+
+ *size = sb.st_size;
+ sym[len] = '\0';
+
+ ret = xstrdup(sym);
+ break;
+ }
+out:
+ closedir(dirp);
+ return ret;
+}
+
+/*
+ * Return the inode number from a string
+ */
+static ino_t get_dev_inode(char *str, dev_t *dev)
+{
+ unsigned int maj = 0, min = 0;
+ ino_t inum = 0;
+
+ if (sscanf(str, "%x:%x:%ju", &maj, &min, &inum) != 3)
+ errx(EXIT_FAILURE, _("failed to parse '%s'"), str);
+
+ *dev = (dev_t) makedev(maj, min);
+ return inum;
+}
+
+static int get_local_locks(struct list_head *locks)
+{
+ int i;
+ FILE *fp;
+ char buf[PATH_MAX], *tok = NULL;
+ size_t sz;
+ struct lock *l;
+
+ if (!(fp = fopen(_PATH_PROC_LOCKS, "r")))
+ return -1;
+
+ while (fgets(buf, sizeof(buf), fp)) {
+
+ l = xcalloc(1, sizeof(*l));
+ INIT_LIST_HEAD(&l->locks);
+
+ for (tok = strtok(buf, " "), i = 0; tok;
+ tok = strtok(NULL, " "), i++) {
+
+ /*
+ * /proc/locks has *exactly* 8 "blocks" of text
+ * separated by ' ' - check <kernel>/fs/locks.c
+ */
+ switch (i) {
+ case 0: /* ID: */
+ tok[strlen(tok) - 1] = '\0';
+ l->id = strtos32_or_err(tok, _("failed to parse ID"));
+ break;
+ case 1: /* posix, flock, etc */
+ if (strcmp(tok, "->") == 0) { /* optional field */
+ l->blocked = 1;
+ i--;
+ } else
+ l->type = xstrdup(tok);
+ break;
+
+ case 2: /* is this a mandatory lock? other values are advisory or noinode */
+ l->mandatory = *tok == 'M' ? 1 : 0;
+ break;
+ case 3: /* lock mode */
+ l->mode = xstrdup(tok);
+ break;
+
+ case 4: /* PID */
+ /*
+ * If user passed a pid we filter it later when adding
+ * to the list, no need to worry now. OFD locks use -1 PID.
+ */
+ l->pid = strtos32_or_err(tok, _("failed to parse pid"));
+ if (l->pid > 0) {
+ l->cmdname = pid_get_cmdname(l->pid);
+ if (!l->cmdname)
+ l->cmdname = xstrdup(_("(unknown)"));
+ } else
+ l->cmdname = xstrdup(_("(undefined)"));
+ break;
+
+ case 5: /* device major:minor and inode number */
+ l->inode = get_dev_inode(tok, &l->dev);
+ break;
+
+ case 6: /* start */
+ l->start = !strcmp(tok, "EOF") ? 0 :
+ strtou64_or_err(tok, _("failed to parse start"));
+ break;
+
+ case 7: /* end */
+ /* replace '\n' character */
+ tok[strlen(tok)-1] = '\0';
+ l->end = !strcmp(tok, "EOF") ? 0 :
+ strtou64_or_err(tok, _("failed to parse end"));
+ break;
+ default:
+ break;
+ }
+ }
+
+ l->path = get_filename_sz(l->inode, l->pid, &sz);
+
+ /* no permissions -- ignore */
+ if (!l->path && no_inaccessible) {
+ rem_lock(l);
+ continue;
+ }
+
+ if (!l->path) {
+ /* probably no permission to peek into l->pid's path */
+ l->path = get_fallback_filename(l->dev);
+ l->size = 0;
+ } else
+ l->size = sz;
+
+ list_add(&l->locks, locks);
+ }
+
+ fclose(fp);
+ return 0;
+}
+
+static int column_name_to_id(const char *name, size_t namesz)
+{
+ size_t i;
+
+ assert(name);
+
+ for (i = 0; i < ARRAY_SIZE(infos); i++) {
+ const char *cn = infos[i].name;
+
+ if (!strncasecmp(name, cn, namesz) && !*(cn + namesz))
+ return i;
+ }
+ warnx(_("unknown column: %s"), name);
+ return -1;
+}
+
+static inline int get_column_id(int num)
+{
+ assert(num >= 0);
+ assert((size_t) num < ncolumns);
+ assert(columns[num] < (int) ARRAY_SIZE(infos));
+
+ return columns[num];
+}
+
+
+static inline struct colinfo *get_column_info(unsigned num)
+{
+ return &infos[ get_column_id(num) ];
+}
+
+static pid_t get_blocker(int id, struct list_head *locks)
+{
+ struct list_head *p;
+
+ list_for_each(p, locks) {
+ struct lock *l = list_entry(p, struct lock, locks);
+
+ if (l->id == id && !l->blocked)
+ return l->pid;
+ }
+
+ return 0;
+}
+
+static void add_scols_line(struct libscols_table *table, struct lock *l, struct list_head *locks)
+{
+ size_t i;
+ struct libscols_line *line;
+ /*
+ * Whenever cmdname or filename is NULL it is most
+ * likely because there's no read permissions
+ * for the specified process.
+ */
+ const char *notfnd = "";
+
+ assert(l);
+ assert(table);
+
+ line = scols_table_new_line(table, NULL);
+ if (!line)
+ err(EXIT_FAILURE, _("failed to allocate output line"));
+
+ for (i = 0; i < ncolumns; i++) {
+ char *str = NULL;
+
+ switch (get_column_id(i)) {
+ case COL_SRC:
+ xasprintf(&str, "%s", l->cmdname ? l->cmdname : notfnd);
+ break;
+ case COL_PID:
+ xasprintf(&str, "%d", l->pid);
+ break;
+ case COL_TYPE:
+ xasprintf(&str, "%s", l->type);
+ break;
+ case COL_INODE:
+ xasprintf(&str, "%ju", (uintmax_t) l->inode);
+ break;
+ case COL_MAJMIN:
+ if (json || raw)
+ xasprintf(&str, "%u:%u", major(l->dev), minor(l->dev));
+ else
+ xasprintf(&str, "%3u:%-3u", major(l->dev), minor(l->dev));
+ break;
+ case COL_SIZE:
+ if (!l->size)
+ break;
+ if (bytes)
+ xasprintf(&str, "%ju", l->size);
+ else
+ str = size_to_human_string(SIZE_SUFFIX_1LETTER, l->size);
+ break;
+ case COL_MODE:
+ xasprintf(&str, "%s%s", l->mode, l->blocked ? "*" : "");
+ break;
+ case COL_M:
+ xasprintf(&str, "%d", l->mandatory ? 1 : 0);
+ break;
+ case COL_START:
+ xasprintf(&str, "%jd", l->start);
+ break;
+ case COL_END:
+ xasprintf(&str, "%jd", l->end);
+ break;
+ case COL_PATH:
+ xasprintf(&str, "%s", l->path ? l->path : notfnd);
+ break;
+ case COL_BLOCKER:
+ {
+ pid_t bl = l->blocked && l->id ?
+ get_blocker(l->id, locks) : 0;
+ if (bl)
+ xasprintf(&str, "%d", (int) bl);
+ }
+ default:
+ break;
+ }
+
+ if (str && scols_line_refer_data(line, i, str))
+ err(EXIT_FAILURE, _("failed to add output data"));
+ }
+}
+
+static int show_locks(struct list_head *locks)
+{
+ int rc = 0;
+ size_t i;
+ struct list_head *p, *pnext;
+ struct libscols_table *table;
+
+ table = scols_new_table();
+ if (!table)
+ err(EXIT_FAILURE, _("failed to allocate output table"));
+
+ scols_table_enable_raw(table, raw);
+ scols_table_enable_json(table, json);
+ scols_table_enable_noheadings(table, no_headings);
+
+ if (json)
+ scols_table_set_name(table, "locks");
+
+ for (i = 0; i < ncolumns; i++) {
+ struct libscols_column *cl;
+ struct colinfo *col = get_column_info(i);
+
+ cl = scols_table_new_column(table, col->name, col->whint, col->flags);
+ if (!cl)
+ err(EXIT_FAILURE, _("failed to allocate output column"));
+
+ if (json) {
+ int id = get_column_id(i);
+
+ switch (id) {
+ case COL_SIZE:
+ if (!bytes)
+ break;
+ /* fallthrough */
+ case COL_PID:
+ case COL_START:
+ case COL_END:
+ case COL_BLOCKER:
+ case COL_INODE:
+ scols_column_set_json_type(cl, SCOLS_JSON_NUMBER);
+ break;
+ case COL_M:
+ scols_column_set_json_type(cl, SCOLS_JSON_BOOLEAN);
+ break;
+ default:
+ scols_column_set_json_type(cl, SCOLS_JSON_STRING);
+ break;
+ }
+ }
+
+ }
+
+ /* prepare data for output */
+ list_for_each(p, locks) {
+ struct lock *l = list_entry(p, struct lock, locks);
+
+ if (pid && pid != l->pid)
+ continue;
+
+ add_scols_line(table, l, locks);
+ }
+
+ /* destroy the list */
+ list_for_each_safe(p, pnext, locks) {
+ struct lock *l = list_entry(p, struct lock, locks);
+ rem_lock(l);
+ }
+
+ scols_print_table(table);
+ scols_unref_table(table);
+ return rc;
+}
+
+
+static void __attribute__((__noreturn__)) usage(void)
+{
+ FILE *out = stdout;
+ size_t i;
+
+ fputs(USAGE_HEADER, out);
+
+ fprintf(out,
+ _(" %s [options]\n"), program_invocation_short_name);
+
+ fputs(USAGE_SEPARATOR, out);
+ fputs(_("List local system locks.\n"), out);
+
+ fputs(USAGE_OPTIONS, out);
+ fputs(_(" -b, --bytes print SIZE in bytes rather than in human readable format\n"), out);
+ fputs(_(" -J, --json use JSON output format\n"), out);
+ fputs(_(" -i, --noinaccessible ignore locks without read permissions\n"), out);
+ fputs(_(" -n, --noheadings don't print headings\n"), out);
+ fputs(_(" -o, --output <list> define which output columns to use\n"), out);
+ fputs(_(" --output-all output all columns\n"), out);
+ fputs(_(" -p, --pid <pid> display only locks held by this process\n"), out);
+ fputs(_(" -r, --raw use the raw output format\n"), out);
+ fputs(_(" -u, --notruncate don't truncate text in columns\n"), out);
+
+ fputs(USAGE_SEPARATOR, out);
+ printf(USAGE_HELP_OPTIONS(24));
+
+ fputs(USAGE_COLUMNS, out);
+
+ for (i = 0; i < ARRAY_SIZE(infos); i++)
+ fprintf(out, " %11s %s\n", infos[i].name, _(infos[i].help));
+
+ printf(USAGE_MAN_TAIL("lslocks(8)"));
+
+ exit(EXIT_SUCCESS);
+}
+
+int main(int argc, char *argv[])
+{
+ int c, rc = 0;
+ struct list_head locks;
+ char *outarg = NULL;
+ enum {
+ OPT_OUTPUT_ALL = CHAR_MAX + 1
+ };
+ static const struct option long_opts[] = {
+ { "bytes", no_argument, NULL, 'b' },
+ { "json", no_argument, NULL, 'J' },
+ { "pid", required_argument, NULL, 'p' },
+ { "help", no_argument, NULL, 'h' },
+ { "output", required_argument, NULL, 'o' },
+ { "output-all", no_argument, NULL, OPT_OUTPUT_ALL },
+ { "notruncate", no_argument, NULL, 'u' },
+ { "version", no_argument, NULL, 'V' },
+ { "noheadings", no_argument, NULL, 'n' },
+ { "raw", no_argument, NULL, 'r' },
+ { "noinaccessible", no_argument, NULL, 'i' },
+ { NULL, 0, NULL, 0 }
+ };
+
+ static const ul_excl_t excl[] = { /* rows and cols in ASCII order */
+ { 'J','r' },
+ { 0 }
+ };
+ int excl_st[ARRAY_SIZE(excl)] = UL_EXCL_STATUS_INIT;
+ setlocale(LC_ALL, "");
+ bindtextdomain(PACKAGE, LOCALEDIR);
+ textdomain(PACKAGE);
+ close_stdout_atexit();
+
+ while ((c = getopt_long(argc, argv,
+ "biJp:o:nruhV", long_opts, NULL)) != -1) {
+
+ err_exclusive_options(c, long_opts, excl, excl_st);
+
+ switch(c) {
+ case 'b':
+ bytes = 1;
+ break;
+ case 'i':
+ no_inaccessible = 1;
+ break;
+ case 'J':
+ json = 1;
+ break;
+ case 'p':
+ pid = strtos32_or_err(optarg, _("invalid PID argument"));
+ break;
+ case 'o':
+ outarg = optarg;
+ break;
+ case OPT_OUTPUT_ALL:
+ for (ncolumns = 0; ncolumns < ARRAY_SIZE(infos); ncolumns++)
+ columns[ncolumns] = ncolumns;
+ break;
+ case 'n':
+ no_headings = 1;
+ break;
+ case 'r':
+ raw = 1;
+ break;
+ case 'u':
+ disable_columns_truncate();
+ break;
+
+ case 'V':
+ print_version(EXIT_SUCCESS);
+ case 'h':
+ usage();
+ default:
+ errtryhelp(EXIT_FAILURE);
+ }
+ }
+
+ INIT_LIST_HEAD(&locks);
+
+ if (!ncolumns) {
+ /* default columns */
+ columns[ncolumns++] = COL_SRC;
+ columns[ncolumns++] = COL_PID;
+ columns[ncolumns++] = COL_TYPE;
+ columns[ncolumns++] = COL_SIZE;
+ columns[ncolumns++] = COL_MODE;
+ columns[ncolumns++] = COL_M;
+ columns[ncolumns++] = COL_START;
+ columns[ncolumns++] = COL_END;
+ columns[ncolumns++] = COL_PATH;
+ }
+
+ if (outarg && string_add_to_idarray(outarg, columns, ARRAY_SIZE(columns),
+ &ncolumns, column_name_to_id) < 0)
+ return EXIT_FAILURE;
+
+ scols_init_debug(0);
+
+ rc = get_local_locks(&locks);
+
+ if (!rc && !list_empty(&locks))
+ rc = show_locks(&locks);
+
+ mnt_unref_table(tab);
+ return rc;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-18 06:53:58 +0000