Put the code to get a unit number from a device name into a common

routine, and use it both on HP-UX and other DLPI systems; this means
that, in case there is ever a network device on HP-UX with a number in
the device type name, we'll properly extract the unit number (i.e.,
we'll extract the last number from the name, not the first number) - I
don't think that'll ever happen, but putting it into a common routine is
cleaner in any case.

diff --git a/pcap-dlpi.c b/pcap-dlpi.c
index f298013c4e09261d07b56d460740b7d02bd1c411..7efff2a7d71e5b85ebfeeb7a020b15f519d3fdea 100644 (file)
--- a/pcap-dlpi.c
+++ b/pcap-dlpi.c
@@ -38,7 +38,7 @@
 
 #ifndef lint
 static const char rcsid[] =
-    "@(#) $Header: /tcpdump/master/libpcap/pcap-dlpi.c,v 1.66 2001-05-21 03:50:08 guy Exp $ (LBL)";
+    "@(#) $Header: /tcpdump/master/libpcap/pcap-dlpi.c,v 1.67 2001-05-21 07:33:56 guy Exp $ (LBL)";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -95,6 +95,7 @@ static const char rcsid[] =
 #define        MAXDLBUF        8192
 
 /* Forwards */
+static char *split_dname(char *, int *, char *);
 static int dlattachreq(int, bpf_u_int32, char *);
 static int dlbindack(int, char *, char *);
 static int dlbindreq(int, bpf_u_int32, char *);
@@ -226,9 +227,8 @@ pcap_t *
 pcap_open_live(char *device, int snaplen, int promisc, int to_ms, char *ebuf)
 {
        register char *cp;
-       char *eos;
        register pcap_t *p;
-       register int ppa;
+       int ppa;
        register dl_info_ack_t *infop;
 #ifdef HAVE_SYS_BUFMOD_H
        bpf_u_int32 ss, flag;
@@ -262,20 +262,12 @@ pcap_open_live(char *device, int snaplen, int promisc, int to_ms, char *ebuf)
        strlcpy(dname, cp, sizeof(dname));
 
        /*
-        * Split the name into a device type and a unit number.
+        * Split the device name into a device type name and a unit number;
+        * chop off the unit number, so "dname" is just a device type name.
         */
-       cp = strpbrk(dname, "0123456789");
-       if (cp == NULL) {
-               snprintf(ebuf, PCAP_ERRBUF_SIZE,
-                   "%s missing unit number", device);
-               goto bad;
-       }
-       ppa = strtol(cp, &eos, 10);
-       if (*eos != '\0') {
-               snprintf(ebuf, PCAP_ERRBUF_SIZE,
-                   "%s bad unit number", device);
+       cp = split_dname(dname, &ppa, ebuf);
+       if (cp == NULL)
                goto bad;
-       }
        *cp = '\0';
 
        /*
@@ -305,33 +297,31 @@ pcap_open_live(char *device, int snaplen, int promisc, int to_ms, char *ebuf)
                goto bad;
 #else
        /*
-       ** Determine device and ppa
-       */
-       cp = device+strlen(device)-1;  /* Start at end of string */
-       if (*cp < '0' || *cp > '9') {
-               snprintf(ebuf, PCAP_ERRBUF_SIZE, "%s missing unit number",
-                   device);
-               goto bad;
-       }
-
-       /* Digits at end of string are unit number */
-       while (cp-1 >= device && *(cp-1) >= '0' && *(cp-1) <= '9')
-               cp--;
-
-       ppa = strtol(cp, &eos, 10);
-       if (*eos != '\0') {
-               snprintf(ebuf, PCAP_ERRBUF_SIZE, "%s bad unit number", device);
+        * Get the unit number, and a pointer to the end of the device
+        * type name.
+        */
+       cp = split_dname(device, &ppa, ebuf);
+       if (cp == NULL)
                goto bad;
-       }
 
+       /*
+        * If the device name begins with "/", assume it begins with
+        * the pathname of the directory containing the device to open;
+        * otherwise, concatenate the device directory name and the
+        * device name.
+        */
        if (*device == '/')
                strlcpy(dname, device, sizeof(dname));
        else
                snprintf(dname, sizeof(dname), "%s/%s", PCAP_DEV_PREFIX,
                    device);
 
+       /*
+        * Make a copy of the device pathname, and then remove the unit
+        * number from the device pathname.
+        */
        strlcpy(dname2, dname, sizeof(dname));
-       *(dname+strlen(dname)-strlen(cp))='\0';
+       *(dname + strlen(dname) - strlen(cp)) = '\0';
 
        /* Try device without unit number */
        if ((p->fd = open(dname, O_RDWR)) < 0) {
@@ -561,6 +551,44 @@ bad:
        return (NULL);
 }
 
+/*
+ * Split a device name into a device type name and a unit number;
+ * return the a pointer to the beginning of the unit number, which
+ * is the end of the device type name, and set "*unitp" to the unit
+ * number.
+ *
+ * Returns NULL on error, and fills "ebuf" with an error message.
+ */
+static char *
+split_dname(char *device, int *unitp, char *ebuf)
+{
+       char *cp;
+       char *eos;
+       int unit;
+
+       /*
+        * Look for a number at the end of the device name string.
+        */
+       cp = device + strlen(device) - 1;
+       if (*cp < '0' || *cp > '9') {
+               snprintf(ebuf, PCAP_ERRBUF_SIZE, "%s missing unit number",
+                   device);
+               return (NULL);
+       }
+
+       /* Digits at end of string are unit number */
+       while (cp-1 >= device && *(cp-1) >= '0' && *(cp-1) <= '9')
+               cp--;
+
+       unit = strtol(cp, &eos, 10);
+       if (*eos != '\0') {
+               snprintf(ebuf, PCAP_ERRBUF_SIZE, "%s bad unit number", device);
+               return (NULL);
+       }
+       *unitp = unit;
+       return (cp);
+}
+
 int
 pcap_setfilter(pcap_t *p, struct bpf_program *fp)
 {