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-rw-r--r--jnlib/dotlock.c374
1 files changed, 0 insertions, 374 deletions
diff --git a/jnlib/dotlock.c b/jnlib/dotlock.c
deleted file mode 100644
index 29ab65dff..000000000
--- a/jnlib/dotlock.c
+++ /dev/null
@@ -1,374 +0,0 @@
-/* dotlock.c - dotfile locking
- * Copyright (C) 1998, 2000 Free Software Foundation, Inc.
- *
- * This file is part of GnuPG.
- *
- * GnuPG 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.
- *
- * GnuPG 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; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
- */
-
-#include <config.h>
-#include <stdlib.h>
-#include <string.h>
-#include <errno.h>
-#include <ctype.h>
-#include <errno.h>
-#include <unistd.h>
-#ifndef HAVE_DOSISH_SYSTEM
-#include <sys/utsname.h>
-#endif
-#include <sys/types.h>
-#include <sys/time.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <signal.h>
-
-#include "libjnlib-config.h"
-#include "dotlock.h"
-
-struct dotlock_handle {
- struct dotlock_handle *next;
- char *tname; /* name of lockfile template */
- char *lockname; /* name of the real lockfile */
- int locked; /* lock status */
- int disable; /* locking */
-};
-
-
-static DOTLOCK all_lockfiles;
-static int never_lock;
-
-static int read_lockfile( const char *name );
-static void remove_lockfiles(void);
-
-void
-disable_dotlock(void)
-{
- never_lock = 1;
-}
-
-/****************
- * Create a lockfile with the given name and return an object of
- * type DOTLOCK which may be used later to actually do the lock.
- * A cleanup routine gets installed to cleanup left over locks
- * or other files used together with the lockmechanism.
- * Althoug the function is called dotlock, this does not necessarily
- * mean that real lockfiles are used - the function may decide to
- * use fcntl locking. Calling the function with NULL only install
- * the atexit handler and maybe used to assure that the cleanup
- * is called after all other atexit handlers.
- *
- * Notes: This function creates a lock file in the same directory
- * as file_to_lock with the name "file_to_lock.lock"
- * A temporary file ".#lk.<hostname>.pid[.threadid] is used.
- * This function does nothing for Windoze.
- */
-DOTLOCK
-create_dotlock( const char *file_to_lock )
-{
- static int initialized;
- DOTLOCK h;
- int fd = -1;
- char pidstr[16];
- #ifndef HAVE_DOSISH_SYSTEM
- struct utsname utsbuf;
- #endif
- const char *nodename;
- const char *dirpart;
- int dirpartlen;
-
- if( !initialized ) {
- atexit( remove_lockfiles );
- initialized = 1;
- }
- if( !file_to_lock )
- return NULL;
-
- h = jnlib_xcalloc( 1, sizeof *h );
- if( never_lock ) {
- h->disable = 1;
- #ifdef _REENTRANT
- /* fixme: aquire mutex on all_lockfiles */
- #endif
- h->next = all_lockfiles;
- all_lockfiles = h;
- return h;
- }
-
-#ifndef HAVE_DOSISH_SYSTEM
- sprintf( pidstr, "%10d\n", (int)getpid() );
- /* fixme: add the hostname to the second line (FQDN or IP addr?) */
-
- /* create a temporary file */
- if( uname( &utsbuf ) )
- nodename = "unknown";
- else
- nodename = utsbuf.nodename;
-
- if( !(dirpart = strrchr( file_to_lock, '/' )) ) {
- dirpart = ".";
- dirpartlen = 1;
- }
- else {
- dirpartlen = dirpart - file_to_lock;
- dirpart = file_to_lock;
- }
-
- #ifdef _REENTRANT
- /* fixme: aquire mutex on all_lockfiles */
- #endif
- h->next = all_lockfiles;
- all_lockfiles = h;
-
- h->tname = jnlib_xmalloc( dirpartlen + 6+30+ strlen(nodename) + 11 );
- sprintf( h->tname, "%.*s/.#lk%p.%s.%d",
- dirpartlen, dirpart, h, nodename, (int)getpid() );
-
- do {
- errno = 0;
- fd = open( h->tname, O_WRONLY|O_CREAT|O_EXCL,
- S_IRUSR|S_IRGRP|S_IROTH|S_IWUSR );
- } while( fd == -1 && errno == EINTR );
- if( fd == -1 ) {
- all_lockfiles = h->next;
- log_error( "failed to create temporary file `%s': %s\n",
- h->tname, strerror(errno));
- jnlib_free(h->tname);
- jnlib_free(h);
- return NULL;
- }
- if( write(fd, pidstr, 11 ) != 11 ) {
- all_lockfiles = h->next;
- #ifdef _REENTRANT
- /* release mutex */
- #endif
- log_fatal( "error writing to `%s': %s\n", h->tname, strerror(errno) );
- close(fd);
- unlink(h->tname);
- jnlib_free(h->tname);
- jnlib_free(h);
- return NULL;
- }
- if( close(fd) ) {
- all_lockfiles = h->next;
- #ifdef _REENTRANT
- /* release mutex */
- #endif
- log_error( "error closing `%s': %s\n", h->tname, strerror(errno));
- unlink(h->tname);
- jnlib_free(h->tname);
- jnlib_free(h);
- return NULL;
- }
-
- #ifdef _REENTRANT
- /* release mutex */
- #endif
-#endif /* !HAVE_DOSISH_SYSTEM */
- h->lockname = jnlib_xmalloc( strlen(file_to_lock) + 6 );
- strcpy(stpcpy(h->lockname, file_to_lock), ".lock");
- return h;
-}
-
-static int
-maybe_deadlock( DOTLOCK h )
-{
- DOTLOCK r;
-
- for( r=all_lockfiles; r; r = r->next ) {
- if( r != h && r->locked )
- return 1;
- }
- return 0;
-}
-
-/****************
- * Do a lock on H. A TIMEOUT of 0 returns immediately,
- * -1 waits forever (hopefully not), other
- * values are timeouts in milliseconds.
- * Returns: 0 on success
- */
-int
-make_dotlock( DOTLOCK h, long timeout )
-{
-#ifdef HAVE_DOSISH_SYSTEM
- return 0;
-#else
- int pid;
- const char *maybe_dead="";
- int backoff=0;
-
- if( h->disable ) {
- return 0;
- }
-
- if( h->locked ) {
- log_debug("oops, `%s' is already locked\n", h->lockname );
- return 0;
- }
-
- for(;;) {
- if( !link(h->tname, h->lockname) ) {
- /* fixme: better use stat to check the link count */
- h->locked = 1;
- return 0; /* okay */
- }
- if( errno != EEXIST ) {
- log_error( "lock not made: link() failed: %s\n", strerror(errno) );
- return -1;
- }
- if( (pid = read_lockfile(h->lockname)) == -1 ) {
- if( errno != ENOENT ) {
- log_info("cannot read lockfile\n");
- return -1;
- }
- log_info( "lockfile disappeared\n");
- continue;
- }
- else if( pid == getpid() ) {
- log_info( "Oops: lock already hold by us\n");
- h->locked = 1;
- return 0; /* okay */
- }
- else if( kill(pid, 0) && errno == ESRCH ) {
- maybe_dead = " - probably dead";
- #if 0 /* we should not do this without checking the permissions */
- /* and the hostname */
- log_info( "removing stale lockfile (created by %d)", pid );
- #endif
- }
- if( timeout == -1 ) {
- struct timeval tv;
- log_info( "waiting for lock (hold by %d%s) %s...\n",
- pid, maybe_dead, maybe_deadlock(h)? "(deadlock?) ":"");
-
-
- /* can't use sleep, cause signals may be blocked */
- tv.tv_sec = 1 + backoff;
- tv.tv_usec = 0;
- select(0, NULL, NULL, NULL, &tv);
- if( backoff < 10 )
- backoff++ ;
- }
- else
- return -1;
- }
- /*not reached */
-#endif /* !HAVE_DOSISH_SYSTEM */
-}
-
-
-/****************
- * release a lock
- * Returns: 0 := success
- */
-int
-release_dotlock( DOTLOCK h )
-{
-#ifdef HAVE_DOSISH_SYSTEM
- return 0;
-#else
- int pid;
-
- if( h->disable ) {
- return 0;
- }
-
- if( !h->locked ) {
- log_debug("oops, `%s' is not locked\n", h->lockname );
- return 0;
- }
-
- pid = read_lockfile( h->lockname );
- if( pid == -1 ) {
- log_error( "release_dotlock: lockfile error\n");
- return -1;
- }
- if( pid != getpid() ) {
- log_error( "release_dotlock: not our lock (pid=%d)\n", pid);
- return -1;
- }
- if( unlink( h->lockname ) ) {
- log_error( "release_dotlock: error removing lockfile `%s'",
- h->lockname);
- return -1;
- }
- /* fixme: check that the link count is now 1 */
- h->locked = 0;
- return 0;
-#endif /* !HAVE_DOSISH_SYSTEM */
-}
-
-
-/****************
- * Read the lock file and return the pid, returns -1 on error.
- */
-static int
-read_lockfile( const char *name )
-{
- #ifdef HAVE_DOSISH_SYSTEM
- return 0;
- #else
- int fd, pid;
- char pidstr[16];
-
- if( (fd = open(name, O_RDONLY)) == -1 ) {
- int e = errno;
- log_debug("error opening lockfile `%s': %s\n", name, strerror(errno) );
- errno = e;
- return -1;
- }
- if( read(fd, pidstr, 10 ) != 10 ) { /* Read 10 digits w/o newline */
- log_debug("error reading lockfile `%s'", name );
- close(fd);
- errno = 0;
- return -1;
- }
- pidstr[10] = 0; /* terminate pid string */
- close(fd);
- pid = atoi(pidstr);
- if( !pid || pid == -1 ) {
- log_error("invalid pid %d in lockfile `%s'", pid, name );
- errno = 0;
- return -1;
- }
- return pid;
- #endif
-}
-
-
-static void
-remove_lockfiles()
-{
- #ifndef HAVE_DOSISH_SYSTEM
- DOTLOCK h, h2;
-
- h = all_lockfiles;
- all_lockfiles = NULL;
-
- while( h ) {
- h2 = h->next;
- if( !h->disable ) {
- if( h->locked )
- unlink( h->lockname );
- unlink(h->tname);
- jnlib_free(h->tname);
- jnlib_free(h->lockname);
- }
- jnlib_free(h);
- h = h2;
- }
- #endif
-}
-
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