New applet, fuser, from Tony J. White. (Needs some cleanup.)

include/applets.h

@@ -258,6 +258,9 @@
 #ifdef CONFIG_FTPPUT
 	APPLET(ftpput, ftpgetput_main, _BB_DIR_USR_BIN, _BB_SUID_NEVER)
 #endif
+#ifdef CONFIG_FUSER
+	APPLET(fuser, fuser_main, _BB_DIR_USR_BIN, _BB_SUID_NEVER)
+#endif
 #ifdef CONFIG_GETOPT
 	APPLET(getopt, getopt_main, _BB_DIR_BIN, _BB_SUID_NEVER)
 #endif

include/usage.h

@@ -841,6 +841,16 @@
 	"\t-p, --password         Password to be used\n" \
 	"\t-P, --port             Port number to be used"
 
+#define fuser_trivial_usage \
+	"[options] file OR port/proto"
+#define fuser_full_usage \
+	"Options:\n" \
+	"\t-m         Show all processes on the same mounted fs\n" \
+	"\t-k         Kill all processes that match.\n" \
+	"\t-s         Don't print or kill anything.\n" \
+	"\t-4         When using port/proto only search IPv4 space\n" \
+	"\t-6         When using port/proto only search IPv6 space\n" \
+	"\t-SIGNAL    When used with -k, this signal will be used to kill\n" 
 #define getopt_trivial_usage \
 	"[OPTIONS]..."
 #define getopt_full_usage \

procps/Config.in

@@ -13,6 +13,14 @@ config CONFIG_FREE
 	  memory in the system, as well as the buffers used by the kernel.
 	  The shared memory column should be ignored; it is obsolete.
 
+config CONFIG_FUSER
+	bool "fuser"
+	default n
+	help
+	  fuser lists all PIDs (Process IDs) that currently have a given 
+	  file open.  fuser can also list all PIDs that have a given network
+	  (TCP or UDP) port open.
+
 config CONFIG_KILL
 	bool "kill"
 	default n
@@ -103,5 +111,6 @@ config CONFIG_UPTIME
 	  the system has been running, how many users are currently logged
 	  on, and the system load averages for the past 1, 5, and 15 minutes.
 
+
 endmenu
 

procps/Makefile.in

@@ -19,6 +19,7 @@ PROCPS-$(CONFIG_RENICE)		+= renice.o
 PROCPS-$(CONFIG_BB_SYSCTL)	+= sysctl.o
 PROCPS-$(CONFIG_TOP)		+= top.o
 PROCPS-$(CONFIG_UPTIME)		+= uptime.o
+PROCPS-$(CONFIG_FUSER)		+= fuser.o
 
 libraries-y+=$(PROCPS_DIR)$(PROCPS_AR)
 

procps/fuser.c

@@ -0,0 +1,386 @@
+/*
+ * tiny fuser implementation 
+ * 
+ * Copyright 2004 Tony J. White
+ *
+ * May be distributed under the conditions of the
+ * GNU Library General Public License
+ */
+
+/* this define is needed for asprintf() */
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <limits.h>
+#include <dirent.h>
+#include <signal.h>
+#include <sys/types.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <sys/socket.h>
+#include "busybox.h"
+
+#define FUSER_PROC_DIR "/proc"
+#define FUSER_MAX_LINE 255
+
+#define FUSER_OPT_MOUNT  1
+#define FUSER_OPT_KILL   2
+#define FUSER_OPT_SILENT 4 
+#define FUSER_OPT_IP6    8 
+#define FUSER_OPT_IP4    16 
+
+typedef struct inode_list {
+	ino_t inode;
+	dev_t dev;
+	struct inode_list *next;
+} inode_list;
+
+typedef struct pid_list {
+	pid_t pid;
+	struct pid_list *next;
+} pid_list;
+
+static int fuser_option(char *option) 
+{
+	int opt = 0;
+
+	if(!(strlen(option))) return 0;
+	if(option[0] != '-') return 0;
+	*++option;
+	while(*option != '\0') {
+		if(*option == 'm') opt |= FUSER_OPT_MOUNT;
+		else if(*option == 'k') opt |= FUSER_OPT_KILL;
+		else if(*option == 's') opt |= FUSER_OPT_SILENT;
+		else if(*option == '6') opt |= FUSER_OPT_IP6;
+		else if(*option == '4') opt |= FUSER_OPT_IP4;
+		else {
+			bb_error_msg_and_die(
+				"Unsupported option '%c'", *option); 
+		}
+		*++option;
+	}
+	return opt;
+}
+
+static int fuser_file_to_dev_inode(const char *filename,
+	 dev_t *dev, ino_t *inode)
+{
+	struct stat f_stat;
+	if((stat(filename, &f_stat)) < 0) return 0;
+	memcpy(inode, &f_stat.st_ino, sizeof(ino_t));
+	memcpy(dev, &f_stat.st_dev, sizeof(dev_t));
+        return 1;
+}
+
+static int fuser_find_socket_dev(dev_t *dev) {
+	int fd = socket(PF_INET, SOCK_DGRAM,0);
+	struct stat buf;
+	
+	if (fd >= 0 && (fstat(fd, &buf)) == 0) {
+		memcpy(dev, &buf.st_dev, sizeof(dev_t));
+		close(fd);
+		return 1;
+	}
+	return 0;
+}
+
+static int fuser_parse_net_arg(const char *filename, 
+	const char **proto, int *port) 
+{
+	int tport;
+	char path[PATH_MAX+1], tproto[5];
+
+	if((sscanf(filename, "%d/%4s", &tport, &tproto[0])) != 2) return 0;
+	strncpy(path, FUSER_PROC_DIR, sizeof(FUSER_PROC_DIR));
+	strncat(path, "/net/", 5);
+	strncat(path, tproto, strlen(tproto)); 
+	if((access(path, R_OK)) != 0) return 0;
+	*proto = bb_xstrndup(tproto, strlen(tproto));
+	memcpy(port, &tport, sizeof(int));
+	return 1;	
+}
+
+static int fuser_add_pid(pid_list *plist, pid_t pid)
+{
+        pid_list *curr = NULL, *last = NULL;
+        
+        if(plist->pid == 0) plist->pid = pid;
+        curr = plist;
+        while(curr != NULL) {
+                if(curr->pid == pid) return 1;
+                last = curr;
+                curr = curr->next;
+        }
+        curr = xmalloc(sizeof(pid_list));
+        last->next = curr;
+        curr->pid = pid;
+	curr->next = NULL;
+        return 1;
+}
+
+static int fuser_add_inode(inode_list *ilist, dev_t dev, ino_t inode)
+{
+        inode_list *curr = NULL, *last = NULL;
+                                                                                
+        if(!ilist->inode && !ilist->dev) {
+		ilist->dev = dev;
+		ilist->inode = inode;
+	}
+        curr = ilist;
+        while(curr != NULL) {
+                if(curr->inode == inode && curr->dev == dev) return 1;
+                last = curr;
+                curr = curr->next;
+        }
+        curr = xmalloc(sizeof(inode_list));
+        last->next = curr;
+        curr->dev = dev;
+        curr->inode = inode;
+	curr->next = NULL;
+        return 1;
+}
+
+static int fuser_scan_proc_net(int opts, const char *proto, 
+	int port, inode_list *ilist) 
+{
+	char path[PATH_MAX+1], line[FUSER_MAX_LINE+1];
+	char addr[128];
+	ino_t tmp_inode;
+	dev_t tmp_dev;
+	int tmp_port;
+	FILE *f;
+
+	if(!fuser_find_socket_dev(&tmp_dev)) tmp_dev = 0;
+	
+	strncpy(path, FUSER_PROC_DIR, sizeof(FUSER_PROC_DIR));
+	strncat(path, "/net/", 5);
+	strncat(path, proto, strlen(proto)); 
+
+	if (!(f = fopen(path, "r"))) return 0;
+	while(fgets(line, FUSER_MAX_LINE, f)) {
+		if(sscanf(line,
+			"%*d: %64[0-9A-Fa-f]:%x %*x:%*x %*x %*x:%*x "
+			"%*x:%*x %*x %*d %*d %lu",
+			&addr[0], &tmp_port, &tmp_inode) == 3) {
+			if((strlen(addr) == 8) && 
+				(opts & FUSER_OPT_IP6)) continue;
+			else if((strlen(addr) > 8) &&
+				(opts & FUSER_OPT_IP4)) continue; 
+			if(tmp_port == port) {
+				fuser_add_inode(ilist, tmp_dev, tmp_inode);
+			}
+		}
+
+	}
+	fclose(f);
+	return 1;
+}
+
+static int fuser_search_dev_inode(int opts, inode_list *ilist, 
+	dev_t dev, ino_t inode) 
+{
+        inode_list *curr;
+        curr = ilist;
+
+        while(curr) {
+		if((opts & FUSER_OPT_MOUNT) &&  curr->dev == dev)
+			return 1;
+		if(curr->inode == inode && curr->dev == dev)
+			return 1;
+                curr = curr->next;
+        }
+        return 0;
+}
+
+static int fuser_scan_pid_maps(int opts, const char *fname, pid_t pid,
+	inode_list *ilist, pid_list *plist) 
+{
+	FILE *file;
+	char line[FUSER_MAX_LINE + 1];
+	int major, minor;
+	ino_t inode;
+	dev_t dev;
+
+	if (!(file = fopen(fname, "r"))) return 0;
+	while (fgets(line, FUSER_MAX_LINE, file)) {
+		if(sscanf(line, "%*s %*s %*s %x:%x %ld", 
+			&major, &minor, &inode) != 3) continue;
+		if(major == 0 && minor == 0 && inode == 0) continue;
+		dev = makedev(major, minor);		
+		if(fuser_search_dev_inode(opts, ilist, dev, inode)) {
+			fuser_add_pid(plist, pid);
+		}
+		
+	}
+	fclose(file);
+	return 1;
+}
+
+static int fuser_scan_link(int opts, const char *lname, pid_t pid, 
+	inode_list *ilist, pid_list *plist) 
+{
+	ino_t inode;
+	dev_t dev;	
+
+	if(!fuser_file_to_dev_inode(lname, &dev, &inode)) return 0;
+	if(fuser_search_dev_inode(opts, ilist, dev, inode)) 
+		fuser_add_pid(plist, pid);
+	return 1;
+}
+
+static int fuser_scan_dir_links(int opts, const char *dname, pid_t pid,
+	inode_list *ilist, pid_list *plist)
+{
+	DIR *d;
+	struct dirent *de;
+	char *lname;
+
+	if((d = opendir(dname))) {
+		while((de = readdir(d)) != NULL) {
+			if(!(strcmp(de->d_name, "."))) continue;
+			if(!(strcmp(de->d_name, ".."))) continue;
+			if(asprintf(&lname, "%s/%s", dname, de->d_name) < 0) {
+				free(lname);
+				continue;
+			}
+			fuser_scan_link(opts, lname, pid, ilist, plist);
+			free(lname);
+		}
+		closedir(d);
+	}
+	else return 0;
+	return 1;
+
+} 
+
+static int fuser_scan_proc_pids(int opts, inode_list *ilist, pid_list *plist) 
+{
+	DIR *d;
+	struct dirent *de;
+	pid_t pid;
+	char *dname;
+
+	if(!(d = opendir(FUSER_PROC_DIR))) return 0;
+	while((de = readdir(d)) != NULL) {
+		pid = (pid_t)atoi(de->d_name);
+		if(!pid) continue;
+		if(asprintf(&dname, "%s/%d/", FUSER_PROC_DIR, pid) < 0) {
+			free(dname);
+			continue;
+		}
+		if(chdir(dname) < 0) {
+			free(dname);
+			continue; 
+		}
+		free(dname);
+		fuser_scan_link(opts, "cwd", pid, ilist, plist);
+		fuser_scan_link(opts, "exe", pid, ilist, plist);
+		fuser_scan_link(opts, "root", pid, ilist, plist);
+		fuser_scan_dir_links(opts, "fd", pid, ilist, plist);
+		fuser_scan_dir_links(opts, "lib", pid, ilist, plist);
+		fuser_scan_dir_links(opts, "mmap", pid, ilist, plist);
+		fuser_scan_pid_maps(opts, "maps", pid, ilist, plist);
+	} 
+	closedir(d);	
+	return 1;
+}
+
+static int fuser_print_pid_list(pid_list *plist) {
+	pid_list *curr;
+	curr = plist;
+
+	if(plist == NULL) return 0;
+	while(curr != NULL) {
+		if(curr->pid > 0) printf("%d ", curr->pid);
+		curr = curr->next;
+	}
+	printf("\n");
+	return 1;
+}
+
+static int fuser_kill_pid_list(pid_list *plist, int sig) {
+        pid_list *curr;
+        curr = plist;
+	pid_t mypid = getpid();
+	int success = 1;
+
+	if(plist == NULL) return 0;
+        while(curr != NULL) {
+		if(curr->pid > 0 && curr->pid != mypid) {
+			if (kill(curr->pid, sig) != 0) { 
+                                bb_perror_msg(
+					"Could not kill pid '%d'", curr->pid);
+				success = 0;		
+			}
+		}
+                curr = curr->next;
+        }
+        return success;
+}
+
+extern int fuser_main(int argc, char **argv) {
+	int port, i, optn;
+	int* fni; /* file name indexes of argv */
+	int fnic = 0;  /* file name index count */
+	const char *proto;
+	static int opt = 0; /* FUSER_OPT_ */
+	dev_t dev;
+	ino_t inode;
+	pid_list *pids;
+	inode_list *inodes;
+	int killsig = SIGTERM;
+	int success = 1;
+
+	fni = xmalloc(sizeof(int));
+	for(i=1;i<argc;i++) {
+		optn = fuser_option(argv[i]);
+		if(optn) opt |= optn; 
+		else if(argv[i][0] == '-') {
+			if(!(u_signal_names(argv[i]+1, &killsig, 0)))
+				killsig = SIGTERM;
+		}
+		else {
+			fni = xrealloc(fni, sizeof(int) * (fnic+2));
+			fni[fnic++] = i;
+		}
+	}
+	if(!fnic) return 1;
+
+	pids = xmalloc(sizeof(pid_list));
+	inodes = xmalloc(sizeof(inode_list));
+	for(i=0;i<fnic;i++) {
+		if(fuser_parse_net_arg(argv[fni[i]], &proto, &port)) {
+			fuser_scan_proc_net(opt, proto, port, inodes);
+		}
+		else {
+			if(!fuser_file_to_dev_inode(
+				argv[fni[i]], &dev, &inode)) {
+				free(pids);
+				free(inodes);
+				bb_perror_msg_and_die(
+					"Could not open '%s'", argv[fni[i]]);
+			}
+			fuser_add_inode(inodes, dev, inode);
+		}
+	}
+	success = fuser_scan_proc_pids(opt, inodes, pids);
+	/* if the first pid in the list is 0, none have been found */
+	if(pids->pid == 0) success = 0;
+	if(success) {
+		if(opt & FUSER_OPT_KILL) {
+			success = fuser_kill_pid_list(pids, killsig);
+		}
+		else if(!(opt & FUSER_OPT_SILENT)) {
+			success = fuser_print_pid_list(pids);
+		}
+	}
+	free(pids);
+	free(inodes);
+	/* return 0 on (success == 1) 1 otherwise */
+	return (success != 1);
+}