add "wpad" DHCP option. Spotted some optimization opportunities: -80 bytes

git-svn-id: svn://busybox.net/trunk/busybox@16644 69ca8d6d-28ef-0310-b511-8ec308f3f277

4 files changed, 64 insertions, 54 deletions

diff --git a/networking/udhcp/files.c b/networking/udhcp/files.c
index 2c2c5422c..829d7e960 100644
--- a/networking/udhcp/files.c
+++ b/networking/udhcp/files.c
@@ -95,7 +95,8 @@ struct option_set *find_option(struct option_set *opt_list, char code)
 
 
 /* add an option to the opt_list */
-static void attach_option(struct option_set **opt_list, struct dhcp_option *option, char *buffer, int length)
+static void attach_option(struct option_set **opt_list,
+                const struct dhcp_option *option, char *buffer, int length)
 {
         struct option_set *existing, *new, **curr;
 
@@ -135,7 +136,7 @@ static int read_opt(const char *const_line, void *arg)
 {
         struct option_set **opt_list = arg;
         char *opt, *val, *endptr;
-        struct dhcp_option *option;
+        const struct dhcp_option *option;
         int retval = 0, length;
         char buffer[8];
         char *line;
@@ -144,16 +145,21 @@ static int read_opt(const char *const_line, void *arg)
 
         /* Cheat, the only const line we'll actually get is "" */
         line = (char *) const_line;
-        if (!(opt = strtok(line, " \t="))) return 0;
+        opt = strtok(line, " \t=");
+        if (!opt) return 0;
 
-        for (option = dhcp_options; option->code; option++)
+        option = dhcp_options;
+        while (1) {
+                if (!option->code)
+                        return 0;
                 if (!strcasecmp(option->name, opt))
                         break;
-
-        if (!option->code) return 0;
+                 option++;
+        }
 
         do {
-                if (!(val = strtok(NULL, ", \t"))) break;
+                val = strtok(NULL, ", \t");
+                if (!val) break;
                 length = option_lengths[option->flags & TYPE_MASK];
                 retval = 0;
                 opt = buffer; /* new meaning for variable opt */
diff --git a/networking/udhcp/options.c b/networking/udhcp/options.c
index 9fcbc8474..4a46da579 100644
--- a/networking/udhcp/options.c
+++ b/networking/udhcp/options.c
@@ -10,53 +10,55 @@
 
 
 /* supported options are easily added here */
-struct dhcp_option dhcp_options[] = {
-        /* name[10]     flags                                   code */
-        {"subnet",      OPTION_IP | OPTION_REQ,                 0x01},
-        {"timezone",    OPTION_S32,                             0x02},
-        {"router",      OPTION_IP | OPTION_LIST | OPTION_REQ,   0x03},
-        {"timesvr",     OPTION_IP | OPTION_LIST,                0x04},
-        {"namesvr",     OPTION_IP | OPTION_LIST,                0x05},
-        {"dns",         OPTION_IP | OPTION_LIST | OPTION_REQ,   0x06},
-        {"logsvr",      OPTION_IP | OPTION_LIST,                0x07},
-        {"cookiesvr",   OPTION_IP | OPTION_LIST,                0x08},
-        {"lprsvr",      OPTION_IP | OPTION_LIST,                0x09},
-        {"hostname",    OPTION_STRING | OPTION_REQ,             0x0c},
-        {"bootsize",    OPTION_U16,                             0x0d},
-        {"domain",      OPTION_STRING | OPTION_REQ,             0x0f},
-        {"swapsvr",     OPTION_IP,                              0x10},
-        {"rootpath",    OPTION_STRING,                          0x11},
-        {"ipttl",       OPTION_U8,                              0x17},
-        {"mtu",         OPTION_U16,                             0x1a},
-        {"broadcast",   OPTION_IP | OPTION_REQ,                 0x1c},
-        {"nisdomain",   OPTION_STRING | OPTION_REQ,             0x28},
-        {"nissrv",      OPTION_IP | OPTION_LIST | OPTION_REQ,   0x29},
-        {"ntpsrv",      OPTION_IP | OPTION_LIST | OPTION_REQ,   0x2a},
-        {"wins",        OPTION_IP | OPTION_LIST,                0x2c},
-        {"requestip",   OPTION_IP,                              0x32},
-        {"lease",       OPTION_U32,                             0x33},
-        {"dhcptype",    OPTION_U8,                              0x35},
-        {"serverid",    OPTION_IP,                              0x36},
-        {"message",     OPTION_STRING,                          0x38},
+const struct dhcp_option dhcp_options[] = {
+        /* name[10]     flags                                   code */
+        {"subnet",      OPTION_IP | OPTION_REQ,                 0x01},
+        {"timezone",    OPTION_S32,                             0x02},
+        {"router",      OPTION_IP | OPTION_LIST | OPTION_REQ,   0x03},
+        {"timesvr",     OPTION_IP | OPTION_LIST,                0x04},
+        {"namesvr",     OPTION_IP | OPTION_LIST,                0x05},
+        {"dns",         OPTION_IP | OPTION_LIST | OPTION_REQ,   0x06},
+        {"logsvr",      OPTION_IP | OPTION_LIST,                0x07},
+        {"cookiesvr",   OPTION_IP | OPTION_LIST,                0x08},
+        {"lprsvr",      OPTION_IP | OPTION_LIST,                0x09},
+        {"hostname",    OPTION_STRING | OPTION_REQ,             0x0c},
+        {"bootsize",    OPTION_U16,                             0x0d},
+        {"domain",      OPTION_STRING | OPTION_REQ,             0x0f},
+        {"swapsvr",     OPTION_IP,                              0x10},
+        {"rootpath",    OPTION_STRING,                          0x11},
+        {"ipttl",       OPTION_U8,                              0x17},
+        {"mtu",         OPTION_U16,                             0x1a},
+        {"broadcast",   OPTION_IP | OPTION_REQ,                 0x1c},
+        {"nisdomain",   OPTION_STRING | OPTION_REQ,             0x28},
+        {"nissrv",      OPTION_IP | OPTION_LIST | OPTION_REQ,   0x29},
+        {"ntpsrv",      OPTION_IP | OPTION_LIST | OPTION_REQ,   0x2a},
+        {"wins",        OPTION_IP | OPTION_LIST,                0x2c},
+        {"requestip",   OPTION_IP,                              0x32},
+        {"lease",       OPTION_U32,                             0x33},
+        {"dhcptype",    OPTION_U8,                              0x35},
+        {"serverid",    OPTION_IP,                              0x36},
+        {"message",     OPTION_STRING,                          0x38},
         {"vendorclass", OPTION_STRING,                          0x3C},
         {"clientid",    OPTION_STRING,                          0x3D},
-        {"tftp",        OPTION_STRING,                          0x42},
-        {"bootfile",    OPTION_STRING,                          0x43},
+        {"tftp",        OPTION_STRING,                          0x42},
+        {"bootfile",    OPTION_STRING,                          0x43},
         {"userclass",   OPTION_STRING,                          0x4D},
-        {"",            0x00,                           0x00}
+        /* MSIE's "Web Proxy Autodiscovery Protocol" support */
+        {"wpad",        OPTION_STRING,                          0xfc},
+        {"",            0x00,                                   0x00}
 };
 
 /* Lengths of the different option types */
-int option_lengths[] = {
-        [OPTION_IP] =           4,
-        [OPTION_IP_PAIR] =      8,
-        [OPTION_BOOLEAN] =      1,
-        [OPTION_STRING] =       1,
-        [OPTION_U8] =           1,
-        [OPTION_U16] =          2,
-        [OPTION_S16] =          2,
-        [OPTION_U32] =          4,
-        [OPTION_S32] =          4
+const unsigned char option_lengths[] = {
+        [OPTION_IP] =      4,
+        [OPTION_IP_PAIR] = 8,
+        [OPTION_BOOLEAN] = 1,
+        [OPTION_STRING] =  1,
+        [OPTION_U8] =      1,
+        [OPTION_U16] =     2,
+        [OPTION_S16] =     2,
+        [OPTION_U32] =     4,
+        [OPTION_S32] =     4
 };
 
 
@@ -150,9 +152,9 @@ int add_option_string(uint8_t *optionptr, uint8_t *string)
 /* add a one to four byte option to a packet */
 int add_simple_option(uint8_t *optionptr, uint8_t code, uint32_t data)
 {
-        struct dhcp_option *dh;
+        const struct dhcp_option *dh;
 
-        for (dh=dhcp_options; dh->code; dh++) {
+        for (dh = dhcp_options; dh->code; dh++) {
                 if (dh->code == code) {
                         uint8_t option[6], len;
 
diff --git a/networking/udhcp/options.h b/networking/udhcp/options.h
index 1b179f173..588504e5d 100644
--- a/networking/udhcp/options.h
+++ b/networking/udhcp/options.h
@@ -26,8 +26,8 @@ struct dhcp_option {
         uint8_t code;
 };
 
-extern struct dhcp_option dhcp_options[];
-extern int option_lengths[];
+extern const struct dhcp_option dhcp_options[];
+extern const unsigned char option_lengths[];
 
 uint8_t *get_option(struct dhcpMessage *packet, int code);
 int end_option(uint8_t *optionptr);
diff --git a/networking/udhcp/script.c b/networking/udhcp/script.c
index 6e0ca885f..d44c80b9f 100644
--- a/networking/udhcp/script.c
+++ b/networking/udhcp/script.c
@@ -54,7 +54,8 @@ static int mton(struct in_addr *mask)
 
 
 /* Fill dest with the text of option 'option'. */
-static void fill_options(char *dest, uint8_t *option, struct dhcp_option *type_p)
+static void fill_options(char *dest, uint8_t *option,
+                        const struct dhcp_option *type_p)
 {
         int type, optlen;
         uint16_t val_u16;
@@ -152,7 +153,8 @@ static char **fill_envp(struct dhcpMessage *packet)
 
 
         for (i = 0; dhcp_options[i].code; i++) {
-                if (!(temp = get_option(packet, dhcp_options[i].code)))
+                temp = get_option(packet, dhcp_options[i].code);
+                if (temp)
                         continue;
                 envp[j] = xmalloc(upper_length(temp[OPT_LEN - 2],
                         dhcp_options[i].flags & TYPE_MASK) + strlen(dhcp_options[i].name) + 2);