package/busybox/patches/340-lock_util.patch

   1 # Copyright (C) 2006 OpenWrt.org
   2 #
   3 # This is free software, licensed under the GNU General Public License v2.
   4 # See /LICENSE for more information.
   5 #
   6 diff -ruN busybox-1.2.0-old/include/applets.h busybox-1.2.0-new/include/applets.h
   7 --- busybox-1.2.0-old/include/applets.h 2006-07-31 11:21:00.000000000 +0200
   8 +++ busybox-1.2.0-new/include/applets.h 2006-08-01 10:21:15.000000000 +0200
   9 @@ -169,6 +169,7 @@
  10  USE_LN(APPLET(ln, _BB_DIR_BIN, _BB_SUID_NEVER))
  11  USE_LOADFONT(APPLET(loadfont, _BB_DIR_USR_BIN, _BB_SUID_NEVER))
  12  USE_LOADKMAP(APPLET(loadkmap, _BB_DIR_SBIN, _BB_SUID_NEVER))
  13 +USE_LOCK(APPLET_NOUSAGE(lock, lock, _BB_DIR_BIN, _BB_SUID_NEVER))
  14  USE_LOGGER(APPLET(logger, _BB_DIR_USR_BIN, _BB_SUID_NEVER))
  15  USE_LOGIN(APPLET(login, _BB_DIR_BIN, _BB_SUID_ALWAYS))
  16  USE_LOGNAME(APPLET(logname, _BB_DIR_USR_BIN, _BB_SUID_NEVER))
  17 diff -ruN busybox-1.2.0-old/miscutils/Config.in busybox-1.2.0-new/miscutils/Config.in
  18 --- busybox-1.2.0-old/miscutils/Config.in       2006-07-01 00:42:09.000000000 +0200
  19 +++ busybox-1.2.0-new/miscutils/Config.in       2006-08-01 10:21:15.000000000 +0200
  20 @@ -231,6 +231,12 @@
  21           Enables the 'hdparm -d' option to get/set using_dma flag.
  22           This is dangerous stuff, so you should probably say N.
  23
  24 +config CONFIG_LOCK
  25 +       bool "lock"
  26 +       default y
  27 +       help
  28 +         Small utility for using locks in scripts
  29 +
  30  config CONFIG_MAKEDEVS
  31         bool "makedevs"
  32         default n
  33 diff -ruN busybox-1.2.0-old/miscutils/lock.c busybox-1.2.0-new/miscutils/lock.c
  34 --- busybox-1.2.0-old/miscutils/lock.c  1970-01-01 01:00:00.000000000 +0100
  35 +++ busybox-1.2.0-new/miscutils/lock.c  2006-08-01 10:21:15.000000000 +0200
  36 @@ -0,0 +1,135 @@
  37 +/*
  38 + * Copyright (C) 2006 Felix Fietkau <nbd@openwrt.org>
  39 + *
  40 + * This is free software, licensed under the GNU General Public License v2.
  41 + */
  42 +#include <sys/types.h>
  43 +#include <sys/file.h>
  44 +#include <sys/stat.h>
  45 +#include <signal.h>
  46 +#include <fcntl.h>
  47 +#include <unistd.h>
  48 +#include <stdio.h>
  49 +#include "busybox.h"
  50 +
  51 +static int unlock = 0;
  52 +static int shared = 0;
  53 +static int waitonly = 0;
  54 +static int fd;
  55 +static char *file;
  56 +
  57 +static void usage(char *name)
  58 +{
  59 +       fprintf(stderr, "Usage: %s [-suw] <filename>\n"
  60 +                       "       -s      Use shared locking\n"
  61 +                       "       -u      Unlock\n"
  62 +                       "       -w      Wait for the lock to become free, don't acquire lock\n"
  63 +                                       "\n", name);
  64 +       exit(1);
  65 +}
  66 +
  67 +static void exit_unlock(int sig)
  68 +{
  69 +       flock(fd, LOCK_UN);
  70 +       unlink(file);
  71 +       exit(0);
  72 +}
  73 +
  74 +static int do_unlock(void)
  75 +{
  76 +       FILE *f;
  77 +       int i;
  78 +
  79 +       if ((f = fopen(file, "r")) == NULL)
  80 +               return 0;
  81 +
  82 +       fscanf(f, "%d", &i);
  83 +       if (i > 0)
  84 +               kill(i, SIGTERM);
  85 +
  86 +       fclose(f);
  87 +
  88 +       return 0;
  89 +}
  90 +
  91 +static int do_lock(void)
  92 +{
  93 +       int pid;
  94 +       char pidstr[8];
  95 +
  96 +       if ((fd = open(file, O_RDWR | O_CREAT | O_EXCL, 0700)) < 0) {
  97 +               if ((fd = open(file, O_RDWR)) < 0) {
  98 +                       fprintf(stderr, "Can't open %s\n", file);
  99 +                       return 1;
 100 +               }
 101 +       }
 102 +
 103 +       if (flock(fd, (shared ? LOCK_SH : LOCK_EX)) < 0) {
 104 +               fprintf(stderr, "Can't lock %s\n", file);
 105 +               return 1;
 106 +       }
 107 +
 108 +       pid = fork();
 109 +
 110 +       if (pid < 0)
 111 +               return -1;
 112 +
 113 +       if (pid == 0) {
 114 +               signal(SIGKILL, exit_unlock);
 115 +               signal(SIGTERM, exit_unlock);
 116 +               signal(SIGINT, exit_unlock);
 117 +               if (waitonly)
 118 +                       exit_unlock(0);
 119 +               else
 120 +                       while (1)
 121 +                               sleep(1);
 122 +       } else {
 123 +               if (!waitonly) {
 124 +                       lseek(fd, 0, SEEK_SET);
 125 +                       ftruncate(fd, 0);
 126 +                       sprintf(pidstr, "%d\n", pid);
 127 +                       write(fd, pidstr, strlen(pidstr));
 128 +                       close(fd);
 129 +               }
 130 +
 131 +               return 0;
 132 +       }
 133 +}
 134 +
 135 +#ifndef CONFIG_LOCK
 136 +int main(int argc, char **argv)
 137 +#else
 138 +int lock_main(int argc, char **argv)
 139 +#endif
 140 +{
 141 +       char **args = &argv[1];
 142 +       int c = argc - 1;
 143 +
 144 +       while ((*args != NULL) && (*args)[0] == '-') {
 145 +               char *ch = *args;
 146 +               while (*(++ch) > 0) {
 147 +                       switch(*ch) {
 148 +                               case 'w':
 149 +                                       waitonly = 1;
 150 +                                       break;
 151 +                               case 's':
 152 +                                       shared = 1;
 153 +                                       break;
 154 +                               case 'u':
 155 +                                       unlock = 1;
 156 +                                       break;
 157 +                       }
 158 +               }
 159 +               c--;
 160 +               args++;
 161 +       }
 162 +
 163 +       if (c != 1)
 164 +               usage(argv[0]);
 165 +
 166 +       file = *args;
 167 +       if (unlock)
 168 +               return do_unlock();
 169 +       else
 170 +               return do_lock();
 171 +}
 172 diff -ruN busybox-1.2.0-old/miscutils/Makefile.in busybox-1.2.0-new/miscutils/Makefile.in
 173 --- busybox-1.2.0-old/miscutils/Makefile.in     2006-07-01 00:42:09.000000000 +0200
 174 +++ busybox-1.2.0-new/miscutils/Makefile.in     2006-08-01 10:21:15.000000000 +0200
 175 @@ -20,6 +20,7 @@
 176  MISCUTILS-$(CONFIG_EJECT)       += eject.o
 177  MISCUTILS-$(CONFIG_HDPARM)      += hdparm.o
 178  MISCUTILS-$(CONFIG_LAST)        += last.o
 179 +MISCUTILS-$(CONFIG_LOCK)        += lock.o
 180  MISCUTILS-${CONFIG_LESS}        += less.o
 181  MISCUTILS-$(CONFIG_MAKEDEVS)    += makedevs.o
 182  MISCUTILS-$(CONFIG_MOUNTPOINT)  += mountpoint.o