Fix ss to handle partial records.

Output from /proc may include partial records, so rather than
trying to be sexy and do own parsing, just use stdio.

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>

diff --git a/misc/ss.c b/misc/ss.c
index 0ac562b7ee1ad9afbc13daa57a83a55d44dabe66..5d14f13295afeb21da9561b8088e2a2b59bb9a96 100644 (file)
--- a/misc/ss.c
+++ b/misc/ss.c
@@ -112,89 +112,86 @@ struct filter default_filter = {
 
 struct filter current_filter;
 
-int generic_proc_open(char *env, char *name)
+static FILE *generic_proc_open(const char *env, const char *name)
 {
+       const char *p = getenv(env);
        char store[128];
-       char *p = getenv(env);
+
        if (!p) {
                p = getenv("PROC_ROOT") ? : "/proc";
                snprintf(store, sizeof(store)-1, "%s/%s", p, name);
                p = store;
        }
-       return open(p, O_RDONLY);
+
+       return fopen(p, "r");
 }
 
-int net_tcp_open(void)
+static FILE *net_tcp_open(void)
 {
        return generic_proc_open("PROC_NET_TCP", "net/tcp");
 }
 
-int net_tcp6_open(void)
+static FILE *net_tcp6_open(void)
 {
        return generic_proc_open("PROC_NET_TCP6", "net/tcp6");
 }
 
-int net_udp_open(void)
+static FILE *net_udp_open(void)
 {
        return generic_proc_open("PROC_NET_UDP", "net/udp");
 }
 
-int net_udp6_open(void)
+static FILE *net_udp6_open(void)
 {
        return generic_proc_open("PROC_NET_UDP6", "net/udp6");
 }
 
-int net_raw_open(void)
+static FILE *net_raw_open(void)
 {
        return generic_proc_open("PROC_NET_RAW", "net/raw");
 }
 
-int net_raw6_open(void)
+static FILE *net_raw6_open(void)
 {
        return generic_proc_open("PROC_NET_RAW6", "net/raw6");
 }
 
-int net_unix_open(void)
+static FILE *net_unix_open(void)
 {
        return generic_proc_open("PROC_NET_UNIX", "net/unix");
 }
 
-int net_packet_open(void)
+static FILE *net_packet_open(void)
 {
        return generic_proc_open("PROC_NET_PACKET", "net/packet");
 }
 
-int net_netlink_open(void)
+static FILE *net_netlink_open(void)
 {
        return generic_proc_open("PROC_NET_NETLINK", "net/netlink");
 }
 
-int slabinfo_open(void)
+static FILE *slabinfo_open(void)
 {
        return generic_proc_open("PROC_SLABINFO", "slabinfo");
 }
 
-int net_sockstat_open(void)
+static FILE *net_sockstat_open(void)
 {
        return generic_proc_open("PROC_NET_SOCKSTAT", "net/sockstat");
 }
 
-int net_sockstat6_open(void)
+static FILE *net_sockstat6_open(void)
 {
        return generic_proc_open("PROC_NET_SOCKSTAT6", "net/sockstat6");
 }
 
-int net_snmp_open(void)
+static FILE *net_snmp_open(void)
 {
        return generic_proc_open("PROC_NET_SNMP", "net/snmp");
 }
 
-int net_netstat_open(void)
-{
-       return generic_proc_open("PROC_NET_NETSTAT", "net/netstat");
-}
-
-int ephemeral_ports_open(void)
+static FILE *ephemeral_ports_open(void)
 {
        return generic_proc_open("PROC_IP_LOCAL_PORT_RANGE", "sys/net/ipv4/ip_local_port_range");
 }
@@ -313,7 +310,8 @@ int get_slabstat(struct slabstat *s)
 
        memset(s, 0, sizeof(*s));
 
-       if ((fp = fdopen(slabinfo_open(), "r")) == NULL)
+       fp = slabinfo_open();
+       if (!fp)
                return -1;
 
        cnt = sizeof(*s)/sizeof(int);
@@ -478,7 +476,7 @@ static int ip_local_port_min, ip_local_port_max;
 static int is_ephemeral(int port)
 {
        if (!ip_local_port_min) {
-               FILE *f = fdopen(ephemeral_ports_open(), "r");
+               FILE *f = ephemeral_ports_open();
                if (f) {
                        fscanf(f, "%d %d",
                               &ip_local_port_min, &ip_local_port_max);
@@ -655,7 +653,7 @@ int run_ssfilter(struct ssfilter *f, struct tcpstat *s)
                        return s->lport < 0;
 
                 if (!low) {
-                       FILE *fp = fdopen(ephemeral_ports_open(), "r");
+                       FILE *fp = ephemeral_ports_open();
                        if (fp) {
                                fscanf(fp, "%d%d", &low, &high);
                                fclose(fp);
@@ -1103,7 +1101,7 @@ void *parse_hostcond(char *addr)
        return res;
 }
 
-static int tcp_show_line(char *line, struct filter *f, int family)
+static int tcp_show_line(char *line, const struct filter *f, int family)
 {
        struct tcpstat s;
        char *loc, *rem, *data;
@@ -1225,68 +1223,30 @@ static int tcp_show_line(char *line, struct filter *f, int family)
        return 0;
 }
 
-static int generic_record_read(int fd, char *buf, int bufsize,
-                       int (*worker)(char*, struct filter *, int),
-                       struct filter *f, int fam)
+static int generic_record_read(FILE *fp,
+                              int (*worker)(char*, const struct filter *, int),
+                              const struct filter *f, int fam)
 {
-       int n;
-       int recsize;
-       int eof = 0;
-       char *p;
+       char line[256];
 
-       /* Load the first chunk and calculate record length from it. */
-       n = read(fd, buf, bufsize);
-       if (n < 0)
+       /* skip header */
+       if (fgets(line, sizeof(line), fp) == NULL)
                goto outerr;
-       /* I _know_ that this is wrong, do not remind. :-)
-        * But this works nowadays. */
-       if (n < bufsize)
-               eof = 1;
-       p = memchr(buf, '\n', n);
-       if (p == NULL || (p-buf) >= n)
-               goto outwrongformat;
-       recsize = (p-buf)+1;
-       p = buf+recsize;
-
-       for (;;) {
-               while ((p+recsize) - buf <= n) {
-                       if (p[recsize-1] != '\n')
-                               goto outwrongformat;
-                       p[recsize-1] = 0;
-                       if (worker(p, f, fam) < 0)
-                               goto done;
-                       p += recsize;
-               }
-               if (!eof) {
-                       int remains = (buf+bufsize) - p;
-                       memcpy(buf, p, remains);
-                       p = buf+remains;
-                       n = read(fd, p, (buf+bufsize) - p);
-                       if (n < 0)
-                               goto outerr;
-                       if (n < (buf+bufsize) - p) {
-                               eof = 1;
-                               if (n == 0) {
-                                       if (remains)
-                                               goto outwrongformat;
-                                       goto done;
-                               }
-                       }
-                       n += remains;
-                       p = buf;
-               } else {
-                       if (p != buf+n)
-                               goto outwrongformat;
-                       goto done;
+
+       while (fgets(line, sizeof(line), fp) != NULL) {
+               int n = strlen(line);
+               if (n == 0 || line[n-1] != '\n') {
+                       errno = -EINVAL;
+                       return -1;
                }
-       }
-done:
-       return 0;
+               line[n-1] = 0;
 
-outwrongformat:
-       errno = EINVAL;
+               if (worker(line, f, fam) < 0)
+                       return 0;
+       }
 outerr:
-       return -1;
+
+       return ferror(fp) ? -1 : 0;
 }
 
 static char *sprint_bw(char *buf, double bw)
@@ -1384,7 +1344,7 @@ static void tcp_show_info(const struct nlmsghdr *nlh, struct inet_diag_msg *r)
        }
 }
 
-int tcp_show_sock(struct nlmsghdr *nlh, struct filter *f)
+static int tcp_show_sock(struct nlmsghdr *nlh, struct filter *f)
 {
        struct inet_diag_msg *r = NLMSG_DATA(nlh);
        struct tcpstat s;
@@ -1447,7 +1407,7 @@ int tcp_show_sock(struct nlmsghdr *nlh, struct filter *f)
        return 0;
 }
 
-int tcp_show_netlink(struct filter *f, FILE *dump_fp, int socktype)
+static int tcp_show_netlink(struct filter *f, FILE *dump_fp, int socktype)
 {
        int fd;
        struct sockaddr_nl nladdr;
@@ -1581,7 +1541,7 @@ skip_it:
        return 0;
 }
 
-int tcp_show_netlink_file(struct filter *f)
+static int tcp_show_netlink_file(struct filter *f)
 {
        FILE    *fp;
        char    buf[8192];
@@ -1637,9 +1597,9 @@ int tcp_show_netlink_file(struct filter *f)
        }
 }
 
-int tcp_show(struct filter *f, int socktype)
+static int tcp_show(struct filter *f, int socktype)
 {
-       int fd = -1;
+       FILE *fp = NULL;
        char *buf = NULL;
        int bufsize = 64*1024;
 
@@ -1654,6 +1614,7 @@ int tcp_show(struct filter *f, int socktype)
 
        /* Sigh... We have to parse /proc/net/tcp... */
 
+
        /* Estimate amount of sockets and try to allocate
         * huge buffer to read all the table at one read.
         * Limit it by 16MB though. The assumption is: as soon as
@@ -1681,18 +1642,21 @@ int tcp_show(struct filter *f, int socktype)
        }
 
        if (f->families & (1<<AF_INET)) {
-               if ((fd = net_tcp_open()) < 0)
+               if ((fp = net_tcp_open()) < 0)
                        goto outerr;
-               if (generic_record_read(fd, buf, bufsize, tcp_show_line, f, AF_INET))
+
+               setbuffer(fp, buf, bufsize);
+               if (generic_record_read(fp, tcp_show_line, f, AF_INET))
                        goto outerr;
-               close(fd);
+               fclose(fp);
        }
 
        if ((f->families & (1<<AF_INET6)) &&
-           (fd = net_tcp6_open()) >= 0) {
-               if (generic_record_read(fd, buf, bufsize, tcp_show_line, f, AF_INET6))
+           (fp = net_tcp6_open()) >= 0) {
+               setbuffer(fp, buf, bufsize);
+               if (generic_record_read(fp, tcp_show_line, f, AF_INET6))
                        goto outerr;
-               close(fd);
+               fclose(fp);
        }
 
        free(buf);
@@ -1703,15 +1667,15 @@ outerr:
                int saved_errno = errno;
                if (buf)
                        free(buf);
-               if (fd >= 0)
-                       close(fd);
+               if (fp)
+                       fclose(fp);
                errno = saved_errno;
                return -1;
        } while (0);
 }
 
 
-int dgram_show_line(char *line, struct filter *f, int family)
+int dgram_show_line(char *line, const struct filter *f, int family)
 {
        struct tcpstat s;
        char *loc, *rem, *data;
@@ -1805,33 +1769,31 @@ int dgram_show_line(char *line, struct filter *f, int family)
 
 int udp_show(struct filter *f)
 {
-       int fd = -1;
-       char buf[8192];
-       int  bufsize = sizeof(buf);
+       FILE *fp = NULL;
 
        dg_proto = UDP_PROTO;
 
        if (f->families&(1<<AF_INET)) {
-               if ((fd = net_udp_open()) < 0)
+               if ((fp = net_udp_open()) < 0)
                        goto outerr;
-               if (generic_record_read(fd, buf, bufsize, dgram_show_line, f, AF_INET))
+               if (generic_record_read(fp, dgram_show_line, f, AF_INET))
                        goto outerr;
-               close(fd);
+               fclose(fp);
        }
 
        if ((f->families&(1<<AF_INET6)) &&
-           (fd = net_udp6_open()) >= 0) {
-               if (generic_record_read(fd, buf, bufsize, dgram_show_line, f, AF_INET6))
+           (fp = net_udp6_open()) >= 0) {
+               if (generic_record_read(fp, dgram_show_line, f, AF_INET6))
                        goto outerr;
-               close(fd);
+               fclose(fp);
        }
        return 0;
 
 outerr:
        do {
                int saved_errno = errno;
-               if (fd >= 0)
-                       close(fd);
+               if (fp)
+                       fclose(fp);
                errno = saved_errno;
                return -1;
        } while (0);
@@ -1839,33 +1801,31 @@ outerr:
 
 int raw_show(struct filter *f)
 {
-       int fd = -1;
-       char buf[8192];
-       int  bufsize = sizeof(buf);
+       FILE *fp = NULL;
 
        dg_proto = RAW_PROTO;
 
        if (f->families&(1<<AF_INET)) {
-               if ((fd = net_raw_open()) < 0)
+               if ((fp = net_raw_open()) < 0)
                        goto outerr;
-               if (generic_record_read(fd, buf, bufsize, dgram_show_line, f, AF_INET))
+               if (generic_record_read(fp, dgram_show_line, f, AF_INET))
                        goto outerr;
-               close(fd);
+               fclose(fp);
        }
 
        if ((f->families&(1<<AF_INET6)) &&
-           (fd = net_raw6_open()) >= 0) {
-               if (generic_record_read(fd, buf, bufsize, dgram_show_line, f, AF_INET6))
+           (fp = net_raw6_open()) >= 0) {
+               if (generic_record_read(fp, dgram_show_line, f, AF_INET6))
                        goto outerr;
-               close(fd);
+               fclose(fp);
        }
        return 0;
 
 outerr:
        do {
                int saved_errno = errno;
-               if (fd >= 0)
-                       close(fd);
+               if (fp)
+                       fclose(fp);
                errno = saved_errno;
                return -1;
        } while (0);
@@ -1970,7 +1930,7 @@ int unix_show(struct filter *f)
        int  cnt;
        struct unixstat *list = NULL;
 
-       if ((fp = fdopen(net_unix_open(), "r")) == NULL)
+       if ((fp = net_unix_open()) == NULL)
                return -1;
        fgets(buf, sizeof(buf)-1, fp);
 
@@ -2058,7 +2018,7 @@ int packet_show(struct filter *f)
        if (!(f->states & (1<<SS_CLOSE)))
                return 0;
 
-       if ((fp = fdopen(net_packet_open(), "r")) == NULL)
+       if ((fp = net_packet_open()) == NULL)
                return -1;
        fgets(buf, sizeof(buf)-1, fp);
 
@@ -2131,7 +2091,7 @@ int netlink_show(struct filter *f)
        if (!(f->states & (1<<SS_CLOSE)))
                return 0;
 
-       if ((fp = fdopen(net_netlink_open(), "r")) == NULL)
+       if ((fp = net_netlink_open()) == NULL)
                return -1;
        fgets(buf, sizeof(buf)-1, fp);
 
@@ -2217,7 +2177,7 @@ int get_snmp_int(char *proto, char *key, int *result)
 
        *result = 0;
 
-       if ((fp = fdopen(net_snmp_open(), "r")) == NULL)
+       if ((fp = net_snmp_open()) == NULL)
                return -1;
 
        while (fgets(buf, sizeof(buf), fp) != NULL) {
@@ -2310,13 +2270,13 @@ int get_sockstat(struct sockstat *s)
 
        memset(s, 0, sizeof(*s));
 
-       if ((fp = fdopen(net_sockstat_open(), "r")) == NULL)
+       if ((fp = net_sockstat_open()) == NULL)
                return -1;
        while(fgets(buf, sizeof(buf), fp) != NULL)
                get_sockstat_line(buf, s);
        fclose(fp);
 
-       if ((fp = fdopen(net_sockstat6_open(), "r")) == NULL)
+       if ((fp = net_sockstat6_open()) == NULL)
                return 0;
        while(fgets(buf, sizeof(buf), fp) != NULL)
                get_sockstat_line(buf, s);