From afa7023b465d2abc5a85ecba0917cae974257eaf Mon Sep 17 00:00:00 2001 From: Denis Vlasenko Date: Mon, 26 Mar 2007 17:25:33 +0000 Subject: [PATCH] zcip: make it work on NOMMU (+ improve NOMMU support machinery) fsck: fix bad English in a comment --- TODO_config_nommu | 6 +- e2fsprogs/fsck.c | 7 +- include/libbb.h | 7 ++ libbb/vfork_daemon_rexec.c | 9 ++- libbb/xfuncs.c | 13 +++- networking/zcip.c | 150 ++++++++++++++++++------------------- 6 files changed, 102 insertions(+), 90 deletions(-) diff --git a/TODO_config_nommu b/TODO_config_nommu index 74095aa9a..695ac1114 100644 --- a/TODO_config_nommu +++ b/TODO_config_nommu @@ -5,7 +5,7 @@ # # Automatically generated make config: don't edit # Busybox version: 1.6.0.svn -# Mon Mar 26 15:00:56 2007 +# Mon Mar 26 18:36:12 2007 # CONFIG_HAVE_DOT_CONFIG=y @@ -266,7 +266,7 @@ CONFIG_RESET=y CONFIG_RESIZE=y CONFIG_FEATURE_RESIZE_PRINT=y CONFIG_SETCONSOLE=y -# CONFIG_FEATURE_SETCONSOLE_LONG_OPTIONS is not set +CONFIG_FEATURE_SETCONSOLE_LONG_OPTIONS=y CONFIG_SETKEYCODES=y CONFIG_SETLOGCONS=y @@ -605,7 +605,7 @@ CONFIG_WGET=y CONFIG_FEATURE_WGET_STATUSBAR=y CONFIG_FEATURE_WGET_AUTHENTICATION=y CONFIG_FEATURE_WGET_LONG_OPTIONS=y -# CONFIG_ZCIP is not set +CONFIG_ZCIP=y # # Process Utilities diff --git a/e2fsprogs/fsck.c b/e2fsprogs/fsck.c index 447b4d008..b70fd7088 100644 --- a/e2fsprogs/fsck.c +++ b/e2fsprogs/fsck.c @@ -509,12 +509,7 @@ static struct fsck_instance *wait_one(int flags) goto ret_inst; } - /* - * gcc -Wall fails saving throw against stupidity - * (inst and prev are thought to be uninitialized variables) - */ - inst = prev = NULL; - + inst = prev = NULL; /* for gcc */ do { pid = waitpid(-1, &status, flags); kill_all_if_cancel_requested(); diff --git a/include/libbb.h b/include/libbb.h index 32e099b54..67fd2af21 100644 --- a/include/libbb.h +++ b/include/libbb.h @@ -263,6 +263,13 @@ char *xrealloc_getcwd_or_warn(char *cwd); char *xmalloc_readlink_or_warn(const char *path); char *xmalloc_realpath(const char *path); extern void xstat(const char *filename, struct stat *buf); +/* Unlike waitpid, waits ONLY for one process, + * It's safe to pass negative 'pids' from failed [v]fork - + * wait4pid will return -1 and ECHILD in errno. + * IOW: rc = wait4pid(spawn(argv)); + * if (rc < 0) bb_perror_msg("%s", argv[0]); + * if (rc > 0) bb_error_msg("exit code: %d", rc); + */ extern int wait4pid(int pid); extern void xsetgid(gid_t gid); extern void xsetuid(uid_t uid); diff --git a/libbb/vfork_daemon_rexec.c b/libbb/vfork_daemon_rexec.c index 89ae9a73c..ec8b9b1d7 100644 --- a/libbb/vfork_daemon_rexec.c +++ b/libbb/vfork_daemon_rexec.c @@ -40,11 +40,14 @@ pid_t spawn(char **argv) * (but don't run atexit() stuff, which would screw up parent.) */ failed = errno; - _exit(0); + _exit(111); } /* parent */ - /* Unfortunately, this is not reliable: vfork() - * can be equivalent to fork() according to standards */ + /* Unfortunately, this is not reliable: according to standards + * vfork() can be equivalent to fork() and we won't see value + * of 'failed'. + * Interested party can wait on pid and learn exit code. + * If 111 - then it (most probably) failed to exec */ if (failed) { errno = failed; return -1; diff --git a/libbb/xfuncs.c b/libbb/xfuncs.c index 14bd62a15..7f870ac8b 100644 --- a/libbb/xfuncs.c +++ b/libbb/xfuncs.c @@ -192,9 +192,16 @@ int wait4pid(int pid) { int status; - if (pid == -1 || waitpid(pid, &status, 0) == -1) return -1; - if (WIFEXITED(status)) return WEXITSTATUS(status); - if (WIFSIGNALED(status)) return WTERMSIG(status); + if (pid <= 0) { + errno = ECHILD; + return -1; + } + if (waitpid(pid, &status, 0) == -1) + return -1; + if (WIFEXITED(status)) + return WEXITSTATUS(status); + if (WIFSIGNALED(status)) + return WTERMSIG(status) + 10000; return 0; } diff --git a/networking/zcip.c b/networking/zcip.c index c0cf665dd..6035b91e1 100644 --- a/networking/zcip.c +++ b/networking/zcip.c @@ -70,10 +70,6 @@ enum { #define VDBG(fmt,args...) \ do { } while (0) -static unsigned opts; -#define FOREGROUND (opts & 1) -#define QUIT (opts & 2) - /** * Pick a random link local IP address on 169.254/16, except that * the first and last 256 addresses are reserved. @@ -128,49 +124,30 @@ static void arp(int fd, struct sockaddr *saddr, int op, } /** - * Run a script. + * Run a script. argv[2] is already NULL. */ -static int run(const char *script, const char *arg, const char *intf, struct in_addr *ip) +static int run(char *argv[3], const char *intf, struct in_addr *ip) { - int pid, status; - const char *why; + int status; - if(1) { //always true: if (script != NULL) - VDBG("%s run %s %s\n", intf, script, arg); - if (ip != NULL) { - char *addr = inet_ntoa(*ip); - setenv("ip", addr, 1); - bb_info_msg("%s %s %s", arg, intf, addr); - } + VDBG("%s run %s %s\n", intf, argv[0], argv[1]); - pid = vfork(); - if (pid < 0) { // error - why = "vfork"; - goto bad; - } else if (pid == 0) { // child - execl(script, script, arg, NULL); - bb_perror_msg("execl"); - _exit(EXIT_FAILURE); - } - - if (waitpid(pid, &status, 0) <= 0) { - why = "waitpid"; - goto bad; - } - if (WEXITSTATUS(status) != 0) { - bb_error_msg("script %s failed, exit=%d", - script, WEXITSTATUS(status)); - return -errno; - } + if (ip) { + char *addr = inet_ntoa(*ip); + setenv("ip", addr, 1); + bb_info_msg("%s %s %s", argv[1], intf, addr); } - return 0; -bad: - status = -errno; - bb_perror_msg("%s %s, %s", arg, intf, why); + + status = wait4pid(spawn(argv)); + if (status < 0) { + bb_perror_msg("%s %s", argv[1], intf); + return -errno; + } + if (status != 0) + bb_error_msg("script %s %s failed, exitcode=%d", argv[0], argv[1], status); return status; } - /** * Return milliseconds of random delay, up to "secs" seconds. */ @@ -182,43 +159,58 @@ static unsigned ATTRIBUTE_ALWAYS_INLINE ms_rdelay(unsigned secs) /** * main program */ - -/* Used to be auto variables on main() stack, but - * most of them were zero-inited. Moving them to bss - * is more space-efficient. - */ -static const struct in_addr null_ip; // = { 0 }; -static const struct ether_addr null_addr; // = { {0, 0, 0, 0, 0, 0} }; - -static struct sockaddr saddr; // memset(0); -static struct in_addr ip; // = { 0 }; -static struct ifreq ifr; //memset(0); - -static char *intf; // = NULL; -static char *script; // = NULL; -static suseconds_t timeout; // = 0; // milliseconds -static unsigned conflicts; // = 0; -static unsigned nprobes; // = 0; -static unsigned nclaims; // = 0; -static int ready; // = 0; -static int verbose; // = 0; -static int state = PROBE; - int zcip_main(int argc, char *argv[]); int zcip_main(int argc, char *argv[]) { + int state = PROBE; struct ether_addr eth_addr; const char *why; int fd; - - // parse commandline: prog [options] ifname script char *r_opt; - opt_complementary = "vv:vf"; // -v accumulates and implies -f + unsigned opts; + + /* Ugly trick, but I want these zeroed in one go */ + struct { + const struct in_addr null_ip; + const struct ether_addr null_addr; + struct sockaddr saddr; + struct in_addr ip; + struct ifreq ifr; + char *intf; + char *script_av[3]; + suseconds_t timeout; // milliseconds + unsigned conflicts; + unsigned nprobes; + unsigned nclaims; + int ready; + int verbose; + } L; +#define null_ip (L.null_ip ) +#define null_addr (L.null_addr) +#define saddr (L.saddr ) +#define ip (L.ip ) +#define ifr (L.ifr ) +#define intf (L.intf ) +#define script_av (L.script_av) +#define timeout (L.timeout ) +#define conflicts (L.conflicts) +#define nprobes (L.nprobes ) +#define nclaims (L.nclaims ) +#define ready (L.ready ) +#define verbose (L.verbose ) + + memset(&L, 0, sizeof(L)); + +#define FOREGROUND (opts & 1) +#define QUIT (opts & 2) + // parse commandline: prog [options] ifname script + // exactly 2 args; -v accumulates and implies -f + opt_complementary = "=2:vv:vf"; opts = getopt32(argc, argv, "fqr:v", &r_opt, &verbose); if (!FOREGROUND) { /* Do it early, before all bb_xx_msg calls */ - logmode = LOGMODE_SYSLOG; openlog(applet_name, 0, LOG_DAEMON); + logmode |= LOGMODE_SYSLOG; } if (opts & 4) { // -r n.n.n.n if (inet_aton(r_opt, &ip) == 0 @@ -227,16 +219,21 @@ int zcip_main(int argc, char *argv[]) bb_error_msg_and_die("invalid link address"); } } + // On NOMMU reexec early (or else we will rerun things twice) +#ifdef BB_NOMMU + if (!FOREGROUND) + bb_daemonize_or_rexec(DAEMON_CHDIR_ROOT, argv); +#endif argc -= optind; argv += optind; - if (argc != 2) - bb_show_usage(); + intf = argv[0]; - script = argv[1]; + script_av[0] = argv[1]; setenv("interface", intf, 1); // initialize the interface (modprobe, ifup, etc) - if (run(script, "init", intf, NULL) < 0) + script_av[1] = (char*)"init"; + if (run(script_av, intf, NULL)) return EXIT_FAILURE; // initialize saddr @@ -271,8 +268,9 @@ int zcip_main(int argc, char *argv[]) // daemonize now; don't delay system startup if (!FOREGROUND) { -//NOMMU +#ifndef BB_NOMMU bb_daemonize(DAEMON_CHDIR_ROOT); +#endif bb_info_msg("start, interface %s", intf); } @@ -375,7 +373,8 @@ int zcip_main(int argc, char *argv[]) state = MONITOR; // link is ok to use earlier // FIXME update filters - run(script, "config", intf, &ip); + script_av[1] = (char*)"config"; + run(script_av, intf, &ip); ready = 1; conflicts = 0; timeout = -1; // Never timeout in the monitor state. @@ -429,8 +428,8 @@ int zcip_main(int argc, char *argv[]) // this shouldn't necessarily exit. bb_error_msg("%s: poll error", intf); if (ready) { - run(script, "deconfig", - intf, &ip); + script_av[1] = (char*)"deconfig"; + run(script_av, intf, &ip); } return EXIT_FAILURE; } @@ -516,7 +515,8 @@ int zcip_main(int argc, char *argv[]) state = PROBE; VDBG("defend conflict -- starting over\n"); ready = 0; - run(script, "deconfig", intf, &ip); + script_av[1] = (char*)"deconfig"; + run(script_av, intf, &ip); // restart the whole protocol pick(&ip); @@ -542,7 +542,7 @@ int zcip_main(int argc, char *argv[]) goto bad; } // switch poll } -bad: + bad: bb_perror_msg("%s, %s", intf, why); return EXIT_FAILURE; }