From 4aca87515a5083ae0e31ce3177189fd43b6d05ac Mon Sep 17 00:00:00 2001 From: Andreas Baumann Date: Sat, 3 Jan 2015 13:58:15 +0100 Subject: patch to Vanilla Tomato 1.28 --- .../src/router/busybox/libbb/find_pid_by_name.c | 261 +++++++-------------- 1 file changed, 89 insertions(+), 172 deletions(-) (limited to 'release/src/router/busybox/libbb/find_pid_by_name.c') diff --git a/release/src/router/busybox/libbb/find_pid_by_name.c b/release/src/router/busybox/libbb/find_pid_by_name.c index 7f39dd41..600d4e1a 100644 --- a/release/src/router/busybox/libbb/find_pid_by_name.c +++ b/release/src/router/busybox/libbb/find_pid_by_name.c @@ -2,198 +2,115 @@ /* * Utility routines. * - * Copyright (C) tons of folks. Tracking down who wrote what - * isn't something I'm going to worry about... If you wrote something - * here, please feel free to acknowledge your work. - * - * This program 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. - * - * This program 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 - * - * Based in part on code from sash, Copyright (c) 1999 by David I. Bell - * Permission has been granted to redistribute this code under the GPL. + * Copyright (C) 1999-2004 by Erik Andersen * + * Licensed under the GPL v2 or later, see the file LICENSE in this tarball. */ -#include -#include -#include -#include -#include #include "libbb.h" -#define READ_BUF_SIZE 50 +/* +In Linux we have three ways to determine "process name": +1. /proc/PID/stat has "...(name)...", among other things. It's so-called "comm" field. +2. /proc/PID/cmdline's first NUL-terminated string. It's argv[0] from exec syscall. +3. /proc/PID/exe symlink. Points to the running executable file. + +kernel threads: + comm: thread name + cmdline: empty + exe: + +executable + comm: first 15 chars of base name + (if executable is a symlink, then first 15 chars of symlink name are used) + cmdline: argv[0] from exec syscall + exe: points to executable (resolves symlink, unlike comm) + +script (an executable with #!/path/to/interpreter): + comm: first 15 chars of script's base name (symlinks are not resolved) + cmdline: /path/to/interpreter (symlinks are not resolved) + (script name is in argv[1], args are pushed into argv[2] etc) + exe: points to interpreter's executable (symlinks are resolved) + +If FEATURE_PREFER_APPLETS=y (and more so if FEATURE_SH_STANDALONE=y), +some commands started from busybox shell, xargs or find are started by +execXXX("/proc/self/exe", applet_name, params....) +and therefore comm field contains "exe". +*/ +static int comm_match(procps_status_t *p, const char *procName) +{ + int argv1idx; -/* For Erik's nifty devps device driver */ -#ifdef BB_FEATURE_USE_DEVPS_PATCH -#include + /* comm does not match */ + if (strncmp(p->comm, procName, 15) != 0) + return 0; -/* find_pid_by_name() - * - * This finds the pid of the specified process, - * by using the /dev/ps device driver. - * - * Returns a list of all matching PIDs - */ -extern pid_t* find_pid_by_name( char* pidName) -{ - int fd, i, j; - char device[] = "/dev/ps"; - pid_t num_pids; - pid_t* pid_array = NULL; - pid_t* pidList=NULL; - - /* open device */ - fd = open(device, O_RDONLY); - if (fd < 0) - perror_msg_and_die("open failed for `%s'", device); - - /* Find out how many processes there are */ - if (ioctl (fd, DEVPS_GET_NUM_PIDS, &num_pids)<0) - perror_msg_and_die("\nDEVPS_GET_PID_LIST"); - - /* Allocate some memory -- grab a few extras just in case - * some new processes start up while we wait. The kernel will - * just ignore any extras if we give it too many, and will trunc. - * the list if we give it too few. */ - pid_array = (pid_t*) xcalloc( num_pids+10, sizeof(pid_t)); - pid_array[0] = num_pids+10; - - /* Now grab the pid list */ - if (ioctl (fd, DEVPS_GET_PID_LIST, pid_array)<0) - perror_msg_and_die("\nDEVPS_GET_PID_LIST"); - - /* Now search for a match */ - for (i=1, j=0; icomm[14] == '\0') /* comm is not truncated - match */ + return 1; - if ((strstr(info.command_line, pidName) != NULL) - && (strlen(pidName) == strlen(info.command_line))) { - pidList=xrealloc( pidList, sizeof(pid_t) * (j+2)); - pidList[j++]=info.pid; - } - } - if (pidList) { - pidList[j]=0; - } else if ( strcmp(pidName, "init")==0) { - /* If we found nothing and they were trying to kill "init", - * guess PID 1 and call it good... Perhaps we should simply - * exit if /proc isn't mounted, but this will do for now. */ - pidList=xrealloc( pidList, sizeof(pid_t)); - pidList[0]=1; - } else { - pidList=xrealloc( pidList, sizeof(pid_t)); - pidList[0]=-1; - } + /* comm is truncated, but first 15 chars match. + * This can be crazily_long_script_name.sh! + * The telltale sign is basename(argv[1]) == procName. */ - /* Free memory */ - free( pid_array); + if (!p->argv0) + return 0; - /* close device */ - if (close (fd) != 0) - perror_msg_and_die("close failed for `%s'", device); + argv1idx = strlen(p->argv0) + 1; + if (argv1idx >= p->argv_len) + return 0; - return pidList; -} + if (strcmp(bb_basename(p->argv0 + argv1idx), procName) != 0) + return 0; -#else /* BB_FEATURE_USE_DEVPS_PATCH */ + return 1; +} -/* find_pid_by_name() - * - * This finds the pid of the specified process. - * Currently, it's implemented by rummaging through - * the proc filesystem. +/* This finds the pid of the specified process. + * Currently, it's implemented by rummaging through + * the proc filesystem. * - * Returns a list of all matching PIDs + * Returns a list of all matching PIDs + * It is the caller's duty to free the returned pidlist. + * + * Modified by Vladimir Oleynik for use with libbb/procps.c */ -extern pid_t* find_pid_by_name( char* pidName) +pid_t* FAST_FUNC find_pid_by_name(const char *procName) { - DIR *dir; - struct dirent *next; - pid_t* pidList=NULL; - int i=0; - - dir = opendir("/proc"); - if (!dir) - perror_msg_and_die("Cannot open /proc"); - - while ((next = readdir(dir)) != NULL) { - FILE *status; - char filename[READ_BUF_SIZE]; - char buffer[READ_BUF_SIZE]; - char name[READ_BUF_SIZE]; - - /* Must skip ".." since that is outside /proc */ - if (strcmp(next->d_name, "..") == 0) - continue; - - /* If it isn't a number, we don't want it */ - if (!isdigit(*next->d_name)) - continue; - - sprintf(filename, "/proc/%s/status", next->d_name); - if (! (status = fopen(filename, "r")) ) { - continue; - } - if (fgets(buffer, READ_BUF_SIZE-1, status) == NULL) { - fclose(status); - continue; - } - fclose(status); - - /* Buffer should contain a string like "Name: binary_name" */ - sscanf(buffer, "%*s %s", name); - if (strcmp(name, pidName) == 0) { - pidList=xrealloc( pidList, sizeof(pid_t) * (i+2)); - pidList[i++]=strtol(next->d_name, NULL, 0); + pid_t* pidList; + int i = 0; + procps_status_t* p = NULL; + + pidList = xzalloc(sizeof(*pidList)); + while ((p = procps_scan(p, PSSCAN_PID|PSSCAN_COMM|PSSCAN_ARGVN))) { + if (comm_match(p, procName) + /* or we require argv0 to match (essential for matching reexeced /proc/self/exe)*/ + || (p->argv0 && strcmp(bb_basename(p->argv0), procName) == 0) + /* TODO: we can also try /proc/NUM/exe link, do we want that? */ + ) { + pidList = xrealloc_vector(pidList, 2, i); + pidList[i++] = p->pid; } } - if (pidList) - pidList[i]=0; - else if ( strcmp(pidName, "init")==0) { - /* If we found nothing and they were trying to kill "init", - * guess PID 1 and call it good... Perhaps we should simply - * exit if /proc isn't mounted, but this will do for now. */ - pidList=xrealloc( pidList, sizeof(pid_t)); - pidList[0]=1; - } else { - pidList=xrealloc( pidList, sizeof(pid_t)); - pidList[0]=-1; - } + pidList[i] = 0; return pidList; } -#endif /* BB_FEATURE_USE_DEVPS_PATCH */ -/* END CODE */ -/* -Local Variables: -c-file-style: "linux" -c-basic-offset: 4 -tab-width: 4 -End: -*/ +pid_t* FAST_FUNC pidlist_reverse(pid_t *pidList) +{ + int i = 0; + while (pidList[i]) + i++; + if (--i >= 0) { + pid_t k; + int j; + for (j = 0; i > j; i--, j++) { + k = pidList[i]; + pidList[i] = pidList[j]; + pidList[j] = k; + } + } + return pidList; +} -- cgit v1.2.3-54-g00ecf