From e125a683a77d14401644d15f38b7f578db723924 Mon Sep 17 00:00:00 2001 From: Denis Vlasenko Date: Sun, 18 May 2008 21:17:52 +0000 Subject: [PATCH] start_stop_daemon: add -test, fix -x to not match by inode, vastly improve hext text. (mostly by Roy Marples ) function old new delta packed_usage 24124 24190 +66 start_stop_daemon_main 959 991 +32 start_stop_daemon_longopts 149 156 +7 check 1632 1589 -43 ------------------------------------------------------------------------------ (add/remove: 0/0 grow/shrink: 3/1 up/down: 105/-43) Total: 62 bytes --- debianutils/start_stop_daemon.c | 134 ++++++++++++++++++++------------ include/usage.h | 83 ++++++++++++-------- 2 files changed, 137 insertions(+), 80 deletions(-) diff --git a/debianutils/start_stop_daemon.c b/debianutils/start_stop_daemon.c index 094b3b18a..524259979 100644 --- a/debianutils/start_stop_daemon.c +++ b/debianutils/start_stop_daemon.c @@ -23,15 +23,18 @@ If --start if given, start a new process unless a matching process was found. Options controlling process matching: -u,--user USERNAME|UID Only consider this user's processes - -n,--name PROCESS_NAME Look for processes with matching argv[0] - or /proc/$PID/exe or /proc/$PID/stat (comm field). + -n,--name PROCESS_NAME Look for processes by matching PROCESS_NAME + with comm field in /proc/$PID/stat. Only basename is compared: "ntpd" == "./ntpd" == "/path/to/ntpd". [TODO: can PROCESS_NAME be a full pathname? Should we require full match then with /proc/$PID/exe or argv[0] (comm can't be matched, it never contains path)] - -x,--exec EXECUTABLE Look for processes with matching /proc/$PID/exe. - Match is performed using device+inode. + -x,--exec EXECUTABLE Look for processes that were started with this + command in /proc/$PID/cmdline. + Unlike -n, we match against the full path: + "ntpd" != "./ntpd" != "/path/to/ntpd" -p,--pidfile PID_FILE Look for processes with PID from this file +If multiple conditions are specified, all must match. Options which are valid for --start only: -x,--exec EXECUTABLE Program to run (1st arg of execvp). Mandatory. @@ -41,8 +44,13 @@ Options which are valid for --start only: -c,--chuid USER[:[GRP]] Change to specified user [and group] -m,--make-pidfile Write PID to the pidfile (both -m and -p must be given!) -Misc options: + +Options which are valid for --stop only: -s,--signal SIG Signal to send (default:TERM) + -t,--test Exit with status 0 if process is found + (we don't actually start or stop daemons) + +Misc options: -o,--oknodo Exit with status 0 if nothing is done -q,--quiet Quiet -v,--verbose Verbose @@ -64,19 +72,21 @@ enum { CTX_START = (1 << 1), OPT_BACKGROUND = (1 << 2), // -b OPT_QUIET = (1 << 3), // -q - OPT_MAKEPID = (1 << 4), // -m - OPT_a = (1 << 5), // -a - OPT_n = (1 << 6), // -n - OPT_s = (1 << 7), // -s - OPT_u = (1 << 8), // -u - OPT_c = (1 << 9), // -c - OPT_x = (1 << 10), // -x - OPT_p = (1 << 11), // -p - OPT_OKNODO = (1 << 12) * ENABLE_FEATURE_START_STOP_DAEMON_FANCY, // -o - OPT_VERBOSE = (1 << 13) * ENABLE_FEATURE_START_STOP_DAEMON_FANCY, // -v - OPT_NICELEVEL = (1 << 14) * ENABLE_FEATURE_START_STOP_DAEMON_FANCY, // -N + OPT_TEST = (1 << 4), // -t + OPT_MAKEPID = (1 << 5), // -m + OPT_a = (1 << 6), // -a + OPT_n = (1 << 7), // -n + OPT_s = (1 << 8), // -s + OPT_u = (1 << 9), // -u + OPT_c = (1 << 10), // -c + OPT_x = (1 << 11), // -x + OPT_p = (1 << 12), // -p + OPT_OKNODO = (1 << 13) * ENABLE_FEATURE_START_STOP_DAEMON_FANCY, // -o + OPT_VERBOSE = (1 << 14) * ENABLE_FEATURE_START_STOP_DAEMON_FANCY, // -v + OPT_NICELEVEL = (1 << 15) * ENABLE_FEATURE_START_STOP_DAEMON_FANCY, // -N }; #define QUIET (option_mask32 & OPT_QUIET) +#define TEST (option_mask32 & OPT_TEST) struct globals { struct pid_list *found; @@ -86,7 +96,6 @@ struct globals { char *pidfile; int user_id; smallint signal_nr; - struct stat execstat; }; #define G (*(struct globals*)&bb_common_bufsiz1) #define found (G.found ) @@ -96,20 +105,23 @@ struct globals { #define pidfile (G.pidfile ) #define user_id (G.user_id ) #define signal_nr (G.signal_nr ) -#define execstat (G.execstat ) #define INIT_G() \ do { \ user_id = -1; \ signal_nr = 15; \ } while (0) - +#ifdef OLDER_VERSION_OF_X +/* -x,--exec EXECUTABLE + * Look for processes with matching /proc/$PID/exe. + * Match is performed using device+inode. + */ static int pid_is_exec(pid_t pid) { struct stat st; char buf[sizeof("/proc//exe") + sizeof(int)*3]; - sprintf(buf, "/proc/%u/exe", pid); + sprintf(buf, "/proc/%u/exe", (unsigned)pid); if (stat(buf, &st) < 0) return 0; if (st.st_dev == execstat.st_dev @@ -117,24 +129,29 @@ static int pid_is_exec(pid_t pid) return 1; return 0; } +#endif -static int pid_is_user(int pid) +static int pid_is_exec(pid_t pid) { - struct stat sb; - char buf[sizeof("/proc/") + sizeof(int)*3]; - - sprintf(buf, "/proc/%u", pid); - if (stat(buf, &sb) != 0) - return 0; - return (sb.st_uid == (uid_t)user_id); + ssize_t bytes; + char buf[PATH_MAX]; + + sprintf(buf, "/proc/%u/cmdline", (unsigned)pid); + bytes = open_read_close(buf, buf, sizeof(buf) - 1); + if (bytes > 0) { + buf[bytes] = '\0'; + return strcmp(buf, execname) == 0; + } + return 0; } -static int pid_is_cmd(pid_t pid) +static int pid_is_name(pid_t pid) { - char buf[256]; /* is it big enough? */ + /* /proc/PID/stat is "PID (comm_15_bytes_max) ..." */ + char buf[32]; /* should be enough */ char *p, *pe; - sprintf(buf, "/proc/%u/stat", pid); + sprintf(buf, "/proc/%u/stat", (unsigned)pid); if (open_read_close(buf, buf, sizeof(buf) - 1) < 0) return 0; buf[sizeof(buf) - 1] = '\0'; /* paranoia */ @@ -145,7 +162,23 @@ static int pid_is_cmd(pid_t pid) if (!pe) return 0; *pe = '\0'; - return !strcmp(p, cmdname); + /* we require comm to match and to not be truncated */ + /* in Linux, if comm is 15 chars, it may be a truncated + * name, so we don't allow that to match */ + if (strlen(p) >= COMM_LEN - 1) /* COMM_LEN is 16 */ + return 0; + return strcmp(p, cmdname) == 0; +} + +static int pid_is_user(int pid) +{ + struct stat sb; + char buf[sizeof("/proc/") + sizeof(int)*3]; + + sprintf(buf, "/proc/%u", (unsigned)pid); + if (stat(buf, &sb) != 0) + return 0; + return (sb.st_uid == (uid_t)user_id); } static void check(int pid) @@ -155,10 +188,10 @@ static void check(int pid) if (execname && !pid_is_exec(pid)) { return; } - if (userspec && !pid_is_user(pid)) { + if (cmdname && !pid_is_name(pid)) { return; } - if (cmdname && !pid_is_cmd(pid)) { + if (userspec && !pid_is_user(pid)) { return; } p = xmalloc(sizeof(*p)); @@ -195,10 +228,11 @@ static void do_procinit(void) procdir = xopendir("/proc"); pid = 0; - while(1) { + while (1) { errno = 0; /* clear any previous error */ entry = readdir(procdir); -// TODO: check for exact errno(s) which mean that we got stale entry +// TODO: this check is too generic, it's better +// to check for exact errno(s) which mean that we got stale entry if (errno) /* Stale entry, process has died after opendir */ continue; if (!entry) /* EOF, no more entries */ @@ -225,12 +259,13 @@ static int do_stop(void) } else if (execname) { if (ENABLE_FEATURE_CLEAN_UP) what = xstrdup(execname); if (!ENABLE_FEATURE_CLEAN_UP) what = execname; - } else if (pidfile) + } else if (pidfile) { what = xasprintf("process in pidfile '%s'", pidfile); - else if (userspec) + } else if (userspec) { what = xasprintf("process(es) owned by '%s'", userspec); - else + } else { bb_error_msg_and_die("internal error, please report"); + } if (!found) { if (!QUIET) @@ -239,18 +274,18 @@ static int do_stop(void) goto ret; } for (p = found; p; p = p->next) { - if (kill(p->pid, signal_nr) == 0) { - p->pid = - p->pid; + if (TEST || kill(p->pid, signal_nr) == 0) { killed++; } else { - bb_perror_msg("warning: killing process %u", p->pid); + p->pid = 0; + bb_perror_msg("warning: killing process %u", (unsigned)p->pid); } } if (!QUIET && killed) { printf("stopped %s (pid", what); for (p = found; p; p = p->next) - if (p->pid < 0) - printf(" %u", - p->pid); + if (p->pid) + printf(" %u", (unsigned)p->pid); puts(")"); } ret: @@ -265,6 +300,7 @@ static const char start_stop_daemon_longopts[] ALIGN1 = "start\0" No_argument "S" "background\0" No_argument "b" "quiet\0" No_argument "q" + "test\0" No_argument "t" "make-pidfile\0" No_argument "m" #if ENABLE_FEATURE_START_STOP_DAEMON_FANCY "oknodo\0" No_argument "o" @@ -291,6 +327,7 @@ int start_stop_daemon_main(int argc ATTRIBUTE_UNUSED, char **argv) char *signame; char *startas; char *chuid; + struct stat execstat; #if ENABLE_FEATURE_START_STOP_DAEMON_FANCY // char *retry_arg = NULL; // int retries = -1; @@ -310,7 +347,7 @@ int start_stop_daemon_main(int argc ATTRIBUTE_UNUSED, char **argv) /* -q turns off -v */ opt_complementary = "K:S:K--S:S--K:m?p:K?xpun:S?xa" USE_FEATURE_START_STOP_DAEMON_FANCY("q-v"); - opt = getopt32(argv, "KSbqma:n:s:u:c:x:p:" + opt = getopt32(argv, "KSbqtma:n:s:u:c:x:p:" USE_FEATURE_START_STOP_DAEMON_FANCY("ovN:"), // USE_FEATURE_START_STOP_DAEMON_FANCY("ovN:R:"), &startas, &cmdname, &signame, &userspec, &chuid, &execname, &pidfile @@ -338,9 +375,6 @@ int start_stop_daemon_main(int argc ATTRIBUTE_UNUSED, char **argv) if (errno) user_id = xuname2uid(userspec); } - if (execname) - xstat(execname, &execstat); - do_procinit(); /* Both start and stop needs to know current processes */ if (opt & CTX_STOP) { @@ -353,6 +387,10 @@ int start_stop_daemon_main(int argc ATTRIBUTE_UNUSED, char **argv) printf("%s already running\n%d\n", execname, found->pid); return !(opt & OPT_OKNODO); } + + if (execname) + xstat(execname, &execstat); + *--argv = startas; if (opt & OPT_BACKGROUND) { #if BB_MMU diff --git a/include/usage.h b/include/usage.h index f912d7b88..56198cfa5 100644 --- a/include/usage.h +++ b/include/usage.h @@ -3613,46 +3613,65 @@ USE_GETOPT_LONG("--start|--stop") SKIP_GETOPT_LONG("-S|-K") \ "] ... [-- arguments...]" #define start_stop_daemon_full_usage "\n\n" \ - "Start and stop services\n" \ - "\nOptions:" \ + "Search for matching processes, and then\n" \ + "-S: stop all matching processes.\n" \ + "-K: start a process unless a matching process is found.\n" \ USE_GETOPT_LONG( \ - "\n -S,--start Start" \ - "\n -K,--stop Stop" \ - "\n -a,--startas pathname Start process specified by pathname" \ - "\n -b,--background Put process into background" \ - "\n -u,--user username|uid Stop this user's processes" \ - "\n -x,--exec executable Program to either start or check" \ - "\n -n,--name process-name Stop processes with this name" \ - "\n -p,--pidfile pid-file Save or load pid using a pid-file" \ - "\n -m,--make-pidfile Create the -p file and enter pid in it" \ - "\n -q,--quiet Quiet" \ + "\nProcess matching:" \ + "\n -u,--user USERNAME|UID Match only this user's processes" \ + "\n -n,--name NAME Match processes with NAME" \ + "\n in comm field in /proc/PID/stat" \ + "\n -x,--exec EXECUTABLE Match processes with this command" \ + "\n in /proc/PID/cmdline" \ + "\n -p,--pidfile FILE Match a process with PID from the file" \ + "\n All specified conditions must match" \ + "\n-K only:" \ + "\n -x,--exec EXECUTABLE Program to run" \ + "\n -a,--startas NAME Zeroth argument" \ + "\n -b,--background Background" \ USE_FEATURE_START_STOP_DAEMON_FANCY( \ - "\n -o,--oknodo Exit status 0 if nothing done" \ - "\n -v,--verbose Verbose" \ - "\n -N,--nicelevel N Add N to process's nice level" \ + "\n -N,--nicelevel N Change nice level" \ ) \ - "\n -s,--signal signal Signal to send (default TERM)" \ - "\n -c,--chuid user[:[grp]] Change to specified user/group" \ + "\n -c,--chuid USER[:[GRP]] Change to user/group" \ + "\n -m,--make-pidfile Write PID to the pidfile specified by -p" \ + "\n-S only:" \ + "\n -s,--signal SIG Signal to send" \ + "\n -t,--test Match only, exit with 0 if a process is found" \ + "\nOther:" \ + USE_FEATURE_START_STOP_DAEMON_FANCY( \ + "\n -o,--oknodo Exit with status 0 if nothing is done" \ + "\n -q,--quiet Quiet" \ + ) \ + "\n -v,--verbose Verbose" \ ) \ SKIP_GETOPT_LONG( \ - "\n -S Start" \ - "\n -K Stop" \ - "\n -a pathname Start process specified by pathname" \ - "\n -b Put process into background" \ - "\n -u username|uid Stop this user's processes" \ - "\n -x executable Program to either start or check" \ - "\n -n process-name Stop processes with this name" \ - "\n -p pid-file Save or load pid using a pid-file" \ - "\n -m Create the -p file and enter pid in it" \ - "\n -q Quiet" \ + "\nProcess matching:" \ + "\n -u USERNAME|UID Match only this user's processes" \ + "\n -n NAME Match processes with NAME" \ + "\n in comm field in /proc/PID/stat" \ + "\n -x EXECUTABLE Match processes with this command" \ + "\n command in /proc/PID/cmdline" \ + "\n -p FILE Match a process with PID from the file" \ + "\n All specified conditions must match" \ + "\n-K only:" \ + "\n -x EXECUTABLE Program to run" \ + "\n -a NAME Zeroth argument" \ + "\n -b Background" \ + USE_FEATURE_START_STOP_DAEMON_FANCY( \ + "\n -N N Change nice level" \ + ) \ + "\n -c USER[:[GRP]] Change to user/group" \ + "\n -m Write PID to the pidfile specified by -p" \ + "\n-S only:" \ + "\n -s SIG Signal to send" \ + "\n -t Match only, exit with 0 if a process is found" \ + "\nOther:" \ USE_FEATURE_START_STOP_DAEMON_FANCY( \ - "\n -o Exit status 0 if nothing done" \ + "\n -o Exit with status 0 if nothing is done" \ + "\n -q Quiet" \ + ) \ "\n -v Verbose" \ - "\n -N N Add N to process's nice level" \ ) \ - "\n -s signal Signal to send (default TERM)" \ - "\n -c user[:[grp]] Change to specified user/group" \ - ) #define stat_trivial_usage \ "[OPTION] FILE..." -- 2.25.1