On Tuesday 19 April 2005 21:10, Tito wrote and today added:
authorlandley <landley@69ca8d6d-28ef-0310-b511-8ec308f3f277>
Sun, 1 May 2005 00:22:03 +0000 (00:22 +0000)
committerlandley <landley@69ca8d6d-28ef-0310-b511-8ec308f3f277>
Sun, 1 May 2005 00:22:03 +0000 (00:22 +0000)
> Hi,
> this is a first attempt of size optimization for zcip taking into account all
> the hints given so far on the list.
> I've applied just the more obvious busyboxifications so maybe it could be
> optimized more.
BTW: I've ripped out  a lot of debug code and changed c++ // comments to /* */
as both were rather confusing for a newbie like me. ;-)
Sorry to the author for that.
I know that this makes mantaining the code easier, but I'm simple minded....

git-svn-id: svn://busybox.net/trunk/busybox@10215 69ca8d6d-28ef-0310-b511-8ec308f3f277

include/libbb.h
libbb/setup_environment.c
networking/zcip.c

index 9daa1cf..f240137 100644 (file)
@@ -430,6 +430,7 @@ extern void run_shell ( const char *shell, int loginshell, const char *command,
 );
 extern int run_parts(char **args, const unsigned char test_mode, char **env);
 extern int restricted_shell ( const char *shell );
+extern void xsetenv ( const char *key, const char *value );
 extern void setup_environment ( const char *shell, int loginshell, int changeenv, const struct passwd *pw );
 extern int correct_password ( const struct passwd *pw );
 extern char *pw_encrypt(const char *clear, const char *salt);
index aeb285a..046ecea 100644 (file)
@@ -42,7 +42,7 @@
 #define DEFAULT_LOGIN_PATH      "/bin:/usr/bin"
 #define DEFAULT_ROOT_LOGIN_PATH "/usr/sbin:/bin:/usr/bin:/sbin"
 
-static void xsetenv ( const char *key, const char *value )
+void xsetenv ( const char *key, const char *value )
 {
            if ( setenv ( key, value, 1 ))
                                bb_error_msg_and_die (bb_msg_memory_exhausted);
index ccf399b..de9ea76 100644 (file)
  * certainly be used.  Its naming is built over multicast DNS.
  */
 
-// #define      DEBUG
-
-// TODO:
-// - more real-world usage/testing, especially daemon mode
-// - kernel packet filters to reduce scheduling noise
-// - avoid silent script failures, especially under load...
-// - link status monitoring (restart on link-up; stop on link-down)
-
+/* TODO:
+ - more real-world usage/testing, especially daemon mode
+ - kernel packet filters to reduce scheduling noise
+ - avoid silent script failures, especially under load...
+ - link status monitoring (restart on link-up; stop on link-down)
+*/
 #include <errno.h>
 #include <stdlib.h>
 #include <stdio.h>
 
 #include <linux/if_packet.h>
 #include <linux/sockios.h>
-
+#include "busybox.h"
+#include "libbb.h"
 
 struct arp_packet {
        struct ether_header hdr;
-       // FIXME this part is netinet/if_ether.h "struct ether_arp"
+       /* FIXME this part is netinet/if_ether.h "struct ether_arp" */
        struct arphdr arp;
        struct ether_addr source_addr;
        struct in_addr source_ip;
@@ -90,29 +89,13 @@ static const unsigned ANNOUNCE_NUM = 2;
 static const unsigned ANNOUNCE_INTERVAL = 2;
 static const time_t DEFEND_INTERVAL = 10;
 
-static const unsigned char ZCIP_VERSION[] = "0.75 (18 April 2005)";
-static char *prog;
+#define ZCIP_VERSION     "0.75 (18 April 2005)"
 
 static const struct in_addr null_ip = { 0 };
 static const struct ether_addr null_addr = { {0, 0, 0, 0, 0, 0} };
 
-static int verbose = 0;
-
-#ifdef DEBUG
-
-#define DBG(fmt,args...) \
-       fprintf(stderr, "%s: " fmt , prog , ## args)
-#define VDBG(fmt,args...) do { \
-       if (verbose) fprintf(stderr, "%s: " fmt , prog ,## args); \
-       } while (0)
-#else
-
-#define DBG(fmt,args...) \
-       do { } while (0)
-#define VDBG   DBG
-#endif                         /* DEBUG */
 
-/**
+/*
  * Pick a random link local IP address on 169.254/16, except that
  * the first and last 256 addresses are reserved.
  */
@@ -128,7 +111,7 @@ pick(struct in_addr *ip)
        ip->s_addr = htonl((LINKLOCAL_ADDR + 0x0100) + tmp);
 }
 
-/**
+/*
  * Broadcast an ARP packet.
  */
 static int
@@ -138,12 +121,12 @@ arp(int fd, struct sockaddr *saddr, int op,
 {
        struct arp_packet p;
 
-       // ether header
+       /* ether header */
        p.hdr.ether_type = htons(ETHERTYPE_ARP);
        memcpy(p.hdr.ether_shost, source_addr, ETH_ALEN);
        memset(p.hdr.ether_dhost, 0xff, ETH_ALEN);
 
-       // arp request
+       /* arp request */
        p.arp.ar_hrd = htons(ARPHRD_ETHER);
        p.arp.ar_pro = htons(ETHERTYPE_IP);
        p.arp.ar_hln = ETH_ALEN;
@@ -154,15 +137,15 @@ arp(int fd, struct sockaddr *saddr, int op,
        memcpy(&p.target_addr, target_addr, ETH_ALEN);
        memcpy(&p.target_ip, &target_ip, sizeof (p.target_ip));
 
-       // send it
+       /* send it */
        if (sendto(fd, &p, sizeof (p), 0, saddr, sizeof (*saddr)) < 0) {
-               perror("sendto");
+               bb_perror_msg("sendto");
                return -errno;
        }
        return 0;
 }
 
-/**
+/*
  * Run a script.
  */
 static int
@@ -172,21 +155,19 @@ run(char *script, char *arg, char *intf, struct in_addr *ip)
        char *why;
 
        if (script != NULL) {
-               VDBG("%s run %s %s\n", intf, script, arg);
                if (ip != NULL) {
                        char *addr = inet_ntoa(*ip);
-                       setenv("ip", addr, 1);
+                       xsetenv("ip", addr);
                        syslog(LOG_INFO, "%s %s %s", arg, intf, addr);
                }
 
                pid = vfork();
-               if (pid < 0) {                  // error
+               if (pid < 0) {                  /* error */
                        why = "vfork";
                        goto bad;
-               } else if (pid == 0) {          // child
+               } else if (pid == 0) {          /* child */
                        execl(script, script, arg, NULL);
-                       perror("execl");
-                       _exit(EXIT_FAILURE);
+                       bb_perror_msg_and_die("execl");
                } 
 
                if (waitpid(pid, &status, 0) <= 0) {
@@ -194,8 +175,7 @@ run(char *script, char *arg, char *intf, struct in_addr *ip)
                        goto bad;
                }
                if (WEXITSTATUS(status) != 0) {
-                       fprintf(stderr, "%s: script %s failed, exit=%d\n",
-                                       prog, script, WEXITSTATUS(status));
+                       bb_perror_msg("script %s failed, exit=%d", script, WEXITSTATUS(status));
                        return -errno;
                }
        }
@@ -207,31 +187,7 @@ bad:
        return status;
 }
 
-#ifndef        NO_BUSYBOX
-#include "busybox.h"
-#endif
-
-/**
- * Print usage information.
- */
-static void __attribute__ ((noreturn))
-usage(const char *msg)
-{
-       fprintf(stderr, "%s: %s\n", prog, msg);
-#ifdef NO_BUSYBOX
-       fprintf(stderr, "Usage: %s [OPTIONS] ifname script\n"
-                       "\t-f              foreground mode (implied by -v)\n"
-                       "\t-q              quit after address (no daemon)\n"
-                       "\t-r 169.254.x.x  request this address first\n"
-                       "\t-v              verbose; show version\n",
-                       prog);
-       exit(0);
-#else
-       bb_show_usage();
-#endif
-}
-
-/**
+/*
  * Return milliseconds of random delay, up to "secs" seconds.
  */
 static inline unsigned
@@ -240,85 +196,72 @@ ms_rdelay(unsigned secs)
        return lrand48() % (secs * 1000);
 }
 
-/**
+/*
  * main program
  */
-int
-main(int argc, char *argv[])
-       __attribute__ ((weak, alias ("zcip_main")));
+
+#define FOREGROUND        1
+#define QUIT              2
+#define REQUEST           4
+#define VERBOSE           8
 
 int zcip_main(int argc, char *argv[])
 {
        char *intf = NULL;
        char *script = NULL;
-       int quit = 0;
-       int foreground = 0;
-
        char *why;
        struct sockaddr saddr;
        struct ether_addr addr;
        struct in_addr ip = { 0 };
        int fd;
        int ready = 0;
-       suseconds_t timeout = 0;        // milliseconds
+       suseconds_t timeout = 0;        /* milliseconds */
        time_t defend = 0;
        unsigned conflicts = 0;
        unsigned nprobes = 0;
        unsigned nclaims = 0;
-       int t;
-
-       // parse commandline: prog [options] ifname script
-       prog = argv[0];
-       while ((t = getopt(argc, argv, "fqr:v")) != EOF) {
-               switch (t) {
-               case 'f':
-                       foreground = 1;
-                       continue;
-               case 'q':
-                       quit = 1;
-                       continue;
-               case 'r':
-                       if (inet_aton(optarg, &ip) == 0
-                                       || (ntohl(ip.s_addr) & IN_CLASSB_NET)
-                                               != LINKLOCAL_ADDR) {
-                               usage("invalid link address");
-                       }
-                       continue;
-               case 'v':
-                       if (!verbose)
-                               printf("%s: version %s\n", prog, ZCIP_VERSION);
-                       verbose++;
-                       foreground = 1;
-                       continue;
-               default:
-                       usage("bad option");
-               }
+       unsigned long t;
+
+       bb_opt_complementaly = "vf";
+       /* parse commandline: prog [options] ifname script */
+       t = bb_getopt_ulflags(argc, argv, "fqr:v", &why); /* reuse char* why */
+       
+       argc -= optind;
+       argv += optind;
+       
+       if ((t & 0x80000000UL) || (argc < 1) || (argc > 2)) {
+               bb_show_usage();
        }
-       if (optind < argc - 1) {
-               intf = argv[optind++];
-               setenv("interface", intf, 1);
-               script = argv[optind++];
+       
+       if (t & VERBOSE) {
+               bb_printf("%s: version %s\n", bb_applet_name, ZCIP_VERSION);
        }
-       if (optind != argc || !intf)
-               usage("wrong number of arguments");
-       openlog(prog, 0, LOG_DAEMON);
-
-       // initialize the interface (modprobe, ifup, etc)
+       if ((t & REQUEST) && (inet_aton(why, &ip) == 0 || (ntohl(ip.s_addr) & IN_CLASSB_NET) != LINKLOCAL_ADDR)) {
+               bb_perror_msg_and_die("invalid link address");
+       }
+       
+       intf = argv[0];
+       xsetenv("interface", intf);
+       script = argv[1]; /* Could be NULL ? */
+       
+       openlog(bb_applet_name, 0, LOG_DAEMON);
+
+       /* initialize the interface (modprobe, ifup, etc) */
        if (run(script, "init", intf, NULL) < 0)
                return EXIT_FAILURE;
 
-       // initialize saddr
+       /* initialize saddr */
        memset(&saddr, 0, sizeof (saddr));
        strncpy(saddr.sa_data, intf, sizeof (saddr.sa_data));
 
-       // open an ARP socket
+       /* open an ARP socket */
        if ((fd = socket(PF_PACKET, SOCK_PACKET, htons(ETH_P_ARP))) < 0) {
                why = "open";
 fail:
-               foreground = 1;
+               t |= FOREGROUND;
                goto bad;
        }
-       // bind to the interface's ARP socket
+       /* bind to the interface's ARP socket */
        if (bind(fd, &saddr, sizeof (saddr)) < 0) {
                why = "bind";
                goto fail;
@@ -326,7 +269,7 @@ fail:
                struct ifreq ifr;
                short seed[3];
 
-               // get the interface's ethernet address
+               /* get the interface's ethernet address */
                memset(&ifr, 0, sizeof (ifr));
                strncpy(ifr.ifr_name, intf, sizeof (ifr.ifr_name));
                if (ioctl(fd, SIOCGIFHWADDR, &ifr) < 0) {
@@ -335,37 +278,37 @@ fail:
                }
                memcpy(&addr, &ifr.ifr_hwaddr.sa_data, ETH_ALEN);
 
-               // start with some stable ip address, either a function of
-               // the hardware address or else the last address we used.
-               // NOTE: the sequence of addresses we try changes only
-               // depending on when we detect conflicts.
+               /* start with some stable ip address, either a function of
+                  the hardware address or else the last address we used.
+                  NOTE: the sequence of addresses we try changes only
+                  depending on when we detect conflicts. */
                memcpy(seed, &ifr.ifr_hwaddr.sa_data, ETH_ALEN);
                seed48(seed);
                if (ip.s_addr == 0)
                        pick(&ip);
        }
 
-       // FIXME cases to handle:
-       //  - zcip already running!
-       //  - link already has local address... just defend/update
+       /* FIXME cases to handle:
+           - zcip already running!
+           - link already has local address... just defend/update */
 
-       // daemonize now; don't delay system startup
-       if (!foreground) {
-               if (daemon(0, verbose) < 0) {
+       /* daemonize now; don't delay system startup */
+       if (!(t & FOREGROUND)) {
+               if (daemon(0, (t & VERBOSE)) < 0) {
                        why = "daemon";
                        goto bad;
                }
                syslog(LOG_INFO, "start, interface %s", intf);
        }
 
-       // run the dynamic address negotiation protocol,
-       // restarting after address conflicts:
-       //  - start with some address we want to try
-       //  - short random delay
-       //  - arp probes to see if another host else uses it
-       //  - arp announcements that we're claiming it
-       //  - use it
-       //  - defend it, within limits
+       /* run the dynamic address negotiation protocol,
+          restarting after address conflicts:
+           - start with some address we want to try
+           - short random delay
+           - arp probes to see if another host else uses it
+           - arp announcements that we're claiming it
+           - use it
+           - defend it, within limits */
        while (1) {
                struct pollfd fds[1];
                struct timeval tv1;
@@ -375,7 +318,7 @@ fail:
                fds[0].events = POLLIN;
                fds[0].revents = 0;
 
-               // poll, being ready to adjust current timeout 
+               /* poll, being ready to adjust current timeout */ 
                if (timeout > 0) {
                        gettimeofday(&tv1, NULL);
                        tv1.tv_usec += (timeout % 1000) * 1000;
@@ -386,21 +329,17 @@ fail:
                        tv1.tv_sec += timeout / 1000;
                } else if (timeout == 0) {
                        timeout = ms_rdelay(PROBE_WAIT);
-                       // FIXME setsockopt(fd, SO_ATTACH_FILTER, ...) to
-                       // make the kernel filter out all packets except
-                       // ones we'd care about.
+                       /* FIXME setsockopt(fd, SO_ATTACH_FILTER, ...) to
+                          make the kernel filter out all packets except
+                          ones we'd care about. */
                }
-               VDBG("...wait %ld %s nprobes=%d, nclaims=%d\n",
-                               timeout, intf, nprobes, nclaims);
                switch (poll(fds, 1, timeout)) {
 
-               // timeouts trigger protocol transitions
+               /* timeouts trigger protocol transitions */
                case 0:
-                       // probes
+                       /* probes */
                        if (nprobes < PROBE_NUM) {
                                nprobes++;
-                               VDBG("probe/%d %s@%s\n",
-                                               nprobes, intf, inet_ntoa(ip));
                                (void)arp(fd, &saddr, ARPOP_REQUEST,
                                                &addr, null_ip,
                                                &null_addr, ip);
@@ -411,38 +350,36 @@ fail:
                                } else
                                        timeout = ANNOUNCE_WAIT * 1000;
                        }
-                       // then announcements
+                       /* then announcements */
                        else if (nclaims < ANNOUNCE_NUM) {
                                nclaims++;
-                               VDBG("announce/%d %s@%s\n",
-                                               nclaims, intf, inet_ntoa(ip));
                                (void)arp(fd, &saddr, ARPOP_REQUEST,
                                                &addr, ip,
                                                &addr, ip);
                                if (nclaims < ANNOUNCE_NUM) {
                                        timeout = ANNOUNCE_INTERVAL * 1000;
                                } else {
-                                       // link is ok to use earlier
+                                       /* link is ok to use earlier */
                                        run(script, "config", intf, &ip);
                                        ready = 1;
                                        conflicts = 0;
                                        timeout = -1;
 
-                                       // NOTE:  all other exit paths
-                                       // should deconfig ...
-                                       if (quit)
+                                       /* NOTE:  all other exit paths
+                                          should deconfig ... */
+                                       if (t & QUIT)
                                                return EXIT_SUCCESS;
-                                       // FIXME update filters
+                                       /* FIXME update filters */
                                }
                        }
                        break;
 
-               // packets arriving
+               /* packets arriving */
                case 1:
-                       // maybe adjust timeout
+                       /* maybe adjust timeout */
                        if (timeout > 0) {
                                struct timeval tv2;
-
+                               
                                gettimeofday(&tv2, NULL);
                                if (timercmp(&tv1, &tv2, <)) {
                                        timeout = -1;
@@ -454,46 +391,33 @@ fail:
                        }
                        if ((fds[0].revents & POLLIN) == 0) {
                                if (fds[0].revents & POLLERR) {
-                                       // FIXME: links routinely go down;
-                                       // this shouldn't necessarily exit.
-                                       fprintf(stderr, "%s %s: poll error\n",
-                                                       prog, intf);
+                                       /* FIXME: links routinely go down;
+                                          this shouldn't necessarily exit. */
+                                       bb_perror_msg("%s: poll error", intf);
                                        if (ready) {
-                                               run(script, "deconfig",
-                                                               intf, &ip);
+                                               run(script, "deconfig", intf, &ip);
                                        }
                                        return EXIT_FAILURE;
                                }
                                continue;
                        }
-                       // read ARP packet
+                       /* read ARP packet */
                        if (recv(fd, &p, sizeof (p), 0) < 0) {
                                why = "recv";
                                goto bad;
                        }
                        if (p.hdr.ether_type != htons(ETHERTYPE_ARP))
                                continue;
-
-                       VDBG("%s recv arp type=%d, op=%d,\n",
-                                       intf, ntohs(p.hdr.ether_type),
-                                       ntohs(p.arp.ar_op));
-                       VDBG("\tsource=%s %s\n",
-                                       ether_ntoa(&p.source_addr),
-                                       inet_ntoa(p.source_ip));
-                       VDBG("\ttarget=%s %s\n",
-                                       ether_ntoa(&p.target_addr),
-                                       inet_ntoa(p.target_ip));
+                       
                        if (p.arp.ar_op != htons(ARPOP_REQUEST)
                                        && p.arp.ar_op != htons(ARPOP_REPLY))
                                continue;
 
-                       // some cases are always conflicts 
+                       /* some cases are always conflicts */ 
                        if ((p.source_ip.s_addr == ip.s_addr)
                                        && (memcmp(&addr, &p.source_addr,
                                                        ETH_ALEN) != 0)) {
 collision:
-                               VDBG("%s ARP conflict from %s\n", intf,
-                                               ether_ntoa(&p.source_addr));
                                if (ready) {
                                        time_t now = time(0);
 
@@ -504,28 +428,26 @@ collision:
                                                                ARPOP_REQUEST,
                                                                &addr, ip,
                                                                &addr, ip);
-                                               VDBG("%s defend\n", intf);
                                                timeout = -1;
                                                continue;
                                        }
                                        defend = now;
                                        ready = 0;
                                        run(script, "deconfig", intf, &ip);
-                                       // FIXME rm filters: setsockopt(fd,
-                                       // SO_DETACH_FILTER, ...)
+                                       /* FIXME rm filters: setsockopt(fd,
+                                          SO_DETACH_FILTER, ...) */
                                }
                                conflicts++;
                                if (conflicts >= MAX_CONFLICTS) {
-                                       VDBG("%s ratelimit\n", intf);
                                        sleep(RATE_LIMIT_INTERVAL);
                                }
-                               // restart the whole protocol
+                               /* restart the whole protocol */
                                pick(&ip);
                                timeout = 0;
                                nprobes = 0;
                                nclaims = 0;
                        }
-                       // two hosts probing one address is a collision too
+                       /* two hosts probing one address is a collision too */
                        else if (p.target_ip.s_addr == ip.s_addr
                                        && nclaims == 0
                                        && p.arp.ar_op == htons(ARPOP_REQUEST)
@@ -541,10 +463,11 @@ collision:
                }
        }
 bad:
-       if (foreground)
-               perror(why);
-       else 
+       if ( t & FOREGROUND) {
+               bb_perror_msg(why);
+       } else { 
                syslog(LOG_ERR, "%s %s, %s error: %s",
-                       prog, intf, why, strerror(errno));
+                       bb_applet_name, intf, why, strerror(errno));
+       }
        return EXIT_FAILURE;
 }