/*
* Utility routines.
*
- * Copyright (C) 1999,2000,2001 by Erik Andersen <andersee@debian.org>
+ * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
*
- * 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
+ * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
*/
-#include <stdio.h>
-#include <ctype.h>
-#include <string.h>
-#include <dirent.h>
-#include <stdlib.h>
#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: <readlink fails>
+
+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;
+ const char *argv1;
-/* For Erik's nifty devps device driver */
-#ifdef CONFIG_FEATURE_USE_DEVPS_PATCH
-#include <linux/devps.h>
+ if (strncmp(p->comm, procName, 15) != 0)
+ return 0; /* comm does not match */
-/* 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; i<pid_array[0] ; i++) {
- char* p;
- struct pid_info info;
-
- info.pid = pid_array[i];
- if (ioctl (fd, DEVPS_GET_PID_INFO, &info)<0)
- perror_msg_and_die("\nDEVPS_GET_PID_INFO");
-
- /* Make sure we only match on the process name */
- p=info.command_line+1;
- while ((*p != 0) && !isspace(*(p)) && (*(p-1) != '\\')) {
- (p)++;
- }
- if (isspace(*(p)))
- *p='\0';
+ /* In Linux, if comm is 15 chars, it is truncated.
+ * (or maybe the name was exactly 15 chars, but there is
+ * no way to know that) */
+ if (p->comm[14] == '\0')
+ return 1; /* comm is not truncated - matches */
- 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;
+ argv1 = p->argv0 + argv1idx;
- return pidList;
-}
+ if (strcmp(bb_basename(argv1), procName) != 0)
+ return 0;
-#else /* CONFIG_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
+ * It is the caller's duty to free the returned pidlist.
*
- * Returns a list of all matching PIDs
+ * 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|PSSCAN_EXE))) {
+ 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)
+ /* or we require /proc/PID/exe link to match */
+ || (p->exe && strcmp(bb_basename(p->exe), procName) == 0)
+ ) {
+ 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 /* CONFIG_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;
+}