package/busybox/patches/340-lock_util.patch

   1
   2         Copyright (C) 2006 OpenWrt.org
   3
   4 diff -urN busybox.old/include/applets.h busybox.dev/include/applets.h
   5 --- busybox.old/include/applets.h       2006-04-05 01:06:29.000000000 +0200
   6 +++ busybox.dev/include/applets.h       2006-04-05 01:19:09.000000000 +0200
   7 @@ -167,6 +167,7 @@
   8  USE_LN(APPLET(ln, ln_main, _BB_DIR_BIN, _BB_SUID_NEVER))
   9  USE_LOADFONT(APPLET(loadfont, loadfont_main, _BB_DIR_USR_BIN, _BB_SUID_NEVER))
  10  USE_LOADKMAP(APPLET(loadkmap, loadkmap_main, _BB_DIR_SBIN, _BB_SUID_NEVER))
  11 +USE_LOCK(APPLET_NOUSAGE(lock, lock_main, _BB_DIR_BIN, _BB_SUID_NEVER))
  12  USE_LOGGER(APPLET(logger, logger_main, _BB_DIR_USR_BIN, _BB_SUID_NEVER))
  13  USE_LOGIN(APPLET(login, login_main, _BB_DIR_BIN, _BB_SUID_ALWAYS))
  14  USE_LOGNAME(APPLET(logname, logname_main, _BB_DIR_USR_BIN, _BB_SUID_NEVER))
  15 diff -urN busybox.old/miscutils/Config.in busybox.dev/miscutils/Config.in
  16 --- busybox.old/miscutils/Config.in     2006-03-22 22:16:24.000000000 +0100
  17 +++ busybox.dev/miscutils/Config.in     2006-04-05 01:07:12.000000000 +0200
  18 @@ -209,6 +209,12 @@
  19           Enables the 'hdparm -d' option to get/set using_dma flag.
  20           This is dangerous stuff, so you should probably say N.
  21
  22 +config CONFIG_LOCK
  23 +       bool "lock"
  24 +       default y
  25 +       help
  26 +         Small utility for using locks in scripts
  27 +
  28  config CONFIG_MAKEDEVS
  29         bool "makedevs"
  30         default n
  31 diff -urN busybox.old/miscutils/Makefile.in busybox.dev/miscutils/Makefile.in
  32 --- busybox.old/miscutils/Makefile.in   2006-03-22 22:16:24.000000000 +0100
  33 +++ busybox.dev/miscutils/Makefile.in   2006-04-05 01:10:50.000000000 +0200
  34 @@ -20,6 +20,7 @@
  35  MISCUTILS-$(CONFIG_EJECT)       += eject.o
  36  MISCUTILS-$(CONFIG_HDPARM)      += hdparm.o
  37  MISCUTILS-$(CONFIG_LAST)        += last.o
  38 +MISCUTILS-$(CONFIG_LOCK)        += lock.o
  39  MISCUTILS-${CONFIG_LESS}        += less.o
  40  MISCUTILS-$(CONFIG_MAKEDEVS)    += makedevs.o
  41  MISCUTILS-$(CONFIG_MOUNTPOINT)  += mountpoint.o
  42 diff -urN busybox.old/miscutils/lock.c busybox.dev/miscutils/lock.c
  43 --- busybox.old/miscutils/lock.c        1970-01-01 01:00:00.000000000 +0100
  44 +++ busybox.dev/miscutils/lock.c        2006-04-05 01:07:12.000000000 +0200
  45 @@ -0,0 +1,133 @@
  46 +/*
  47 + * Copyright (C) 2006 Felix Fietkau <nbd@openwrt.org>
  48 + *
  49 + * This is free software, licensed under the GNU General Public License v2.
  50 + */
  51 +#include <sys/types.h>
  52 +#include <sys/file.h>
  53 +#include <sys/stat.h>
  54 +#include <signal.h>
  55 +#include <fcntl.h>
  56 +#include <unistd.h>
  57 +#include <stdio.h>
  58 +#include "busybox.h"
  59 +
  60 +static int unlock = 0;
  61 +static int shared = 0;
  62 +static int waitonly = 0;
  63 +static int fd;
  64 +static char *file;
  65 +
  66 +static void usage(char *name)
  67 +{
  68 +       fprintf(stderr, "Usage: %s [-suw] <filename>\n"
  69 +                       "       -s      Use shared locking\n"
  70 +                       "       -u      Unlock\n"
  71 +                       "       -w      Wait for the lock to become free, don't acquire lock\n"
  72 +                                       "\n", name);
  73 +       exit(1);
  74 +}
  75 +
  76 +static void exit_unlock(int sig)
  77 +{
  78 +       flock(fd, LOCK_UN);
  79 +       unlink(file);
  80 +       exit(0);
  81 +}
  82 +
  83 +static int do_unlock(void)
  84 +{
  85 +       FILE *f;
  86 +       int i;
  87 +
  88 +       if ((f = fopen(file, "r")) == NULL)
  89 +               return 0;
  90 +
  91 +       fscanf(f, "%d", &i);
  92 +       if (i > 0)
  93 +               kill(i, SIGTERM);
  94 +
  95 +       fclose(f);
  96 +
  97 +       return 0;
  98 +}
  99 +
 100 +static int do_lock(void)
 101 +{
 102 +       int pid;
 103 +       char pidstr[8];
 104 +
 105 +       if ((fd = open(file, O_RDWR | O_CREAT, 0700)) < 0) {
 106 +               fprintf(stderr, "Can't open %s\n", file);
 107 +               return 1;
 108 +       }
 109 +
 110 +       if (flock(fd, (shared ? LOCK_SH : LOCK_EX)) < 0) {
 111 +               fprintf(stderr, "Can't lock %s\n", file);
 112 +               return 1;
 113 +       }
 114 +
 115 +       pid = fork();
 116 +
 117 +       if (pid < 0)
 118 +               return -1;
 119 +
 120 +       if (pid == 0) {
 121 +               signal(SIGKILL, exit_unlock);
 122 +               signal(SIGTERM, exit_unlock);
 123 +               signal(SIGINT, exit_unlock);
 124 +               if (waitonly)
 125 +                       exit_unlock(0);
 126 +               else
 127 +                       while (1)
 128 +                               sleep(1);
 129 +       } else {
 130 +               if (!waitonly) {
 131 +                       lseek(fd, 0, SEEK_SET);
 132 +                       ftruncate(fd, 0);
 133 +                       sprintf(pidstr, "%d\n", pid);
 134 +                       write(fd, pidstr, strlen(pidstr));
 135 +                       close(fd);
 136 +               }
 137 +
 138 +               return 0;
 139 +       }
 140 +}
 141 +
 142 +#ifndef CONFIG_LOCK
 143 +int main(int argc, char **argv)
 144 +#else
 145 +int lock_main(int argc, char **argv)
 146 +#endif
 147 +{
 148 +       char **args = &argv[1];
 149 +       int c = argc - 1;
 150 +
 151 +       while ((*args != NULL) && (*args)[0] == '-') {
 152 +               char *ch = *args;
 153 +               while (*(++ch) > 0) {
 154 +                       switch(*ch) {
 155 +                               case 'w':
 156 +                                       waitonly = 1;
 157 +                                       break;
 158 +                               case 's':
 159 +                                       shared = 1;
 160 +                                       break;
 161 +                               case 'u':
 162 +                                       unlock = 1;
 163 +                                       break;
 164 +                       }
 165 +               }
 166 +               c--;
 167 +               args++;
 168 +       }
 169 +
 170 +       if (c != 1)
 171 +               usage(argv[0]);
 172 +
 173 +       file = *args;
 174 +       if (unlock)
 175 +               return do_unlock();
 176 +       else
 177 +               return do_lock();
 178 +}