adb: Transmit key properties in banner of connect message

protocol.txt says that the connect message should have three
fields:

        <systemtype>:<serialno>:<banner>

In reality, what is transmitted is simply:

        <systemtype>::

The serialno is obtained via other means so doesn't really need
to be a part of the connect message.  This change puts the
ro.product.name, ro.product.model and ro.product.device
properties in the <banner> for devices.  Each property is
terminated by a semicolon (;) with the key and value separated by
an equals sign (=).  Example message:

device::ro.product.name=<prd>;ro.product.model=<mdl>;ro.product.device=<dev>;

Making this change will enable the device list to provide more
information to the user and to give the potential for being able
to select which device to talk to with the -s option.

Change-Id: I09200decde4facb8fc9b4056fdae910155f2bcb9
Signed-off-by: Scott Anderson <saa@android.com>

adb/adb.c

@@ -29,6 +29,8 @@
 #include "sysdeps.h"
 #include "adb.h"
 
+#define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))
+
 #if !ADB_HOST
 #include <private/android_filesystem_config.h>
 #include <linux/capability.h>
@@ -43,7 +45,9 @@ ADB_MUTEX_DEFINE( D_lock );
 
 int HOST = 0;
 
+#if !ADB_HOST
 static const char *adb_device_banner = "device";
+#endif
 
 void fatal(const char *fmt, ...)
 {
@@ -218,6 +222,36 @@ static void send_close(unsigned local, unsigned remote, atransport *t)
     send_packet(p, t);
 }
 
+static size_t fill_connect_data(char *buf, size_t bufsize)
+{
+#if ADB_HOST
+    return snprintf(buf, bufsize, "host::") + 1;
+#else
+    static const char *cnxn_props[] = {
+        "ro.product.name",
+        "ro.product.model",
+        "ro.product.device",
+    };
+    static const int num_cnxn_props = ARRAY_SIZE(cnxn_props);
+    int i;
+    size_t remaining = bufsize;
+    size_t len;
+
+    len = snprintf(buf, remaining, "%s::", adb_device_banner);
+    remaining -= len;
+    buf += len;
+    for (i = 0; i < num_cnxn_props; i++) {
+        char value[PROPERTY_VALUE_MAX];
+        property_get(cnxn_props[i], value, "");
+        len = snprintf(buf, remaining, "%s=%s;", cnxn_props[i], value);
+        remaining -= len;
+        buf += len;
+    }
+
+    return bufsize - remaining + 1;
+#endif
+}
+
 static void send_connect(atransport *t)
 {
     D("Calling send_connect \n");
@@ -225,9 +259,8 @@ static void send_connect(atransport *t)
     cp->msg.command = A_CNXN;
     cp->msg.arg0 = A_VERSION;
     cp->msg.arg1 = MAX_PAYLOAD;
-    snprintf((char*) cp->data, sizeof cp->data, "%s::",
-            HOST ? "host" : adb_device_banner);
-    cp->msg.data_length = strlen((char*) cp->data) + 1;
+    cp->msg.data_length = fill_connect_data((char *)cp->data,
+                                            sizeof(cp->data));
     send_packet(cp, t);
 #if ADB_HOST
         /* XXX why sleep here? */
@@ -254,29 +287,57 @@ static char *connection_state_name(atransport *t)
     }
 }
 
+/* qual_overwrite is used to overwrite a qualifier string.  dst is a
+ * pointer to a char pointer.  It is assumed that if *dst is non-NULL, it
+ * was malloc'ed and needs to freed.  A char buffer will be malloc'ed and
+ * filled with src and *dst will be set to
+ * point to the buffer.
+ */
+static void qual_overwrite(char **dst, const char *src)
+{
+    if (!dst)
+        return;
+
+    free(*dst);
+    *dst = NULL;
+
+    if (!src || !*src)
+        return;
+
+    *dst = strdup(src);
+}
+
 void parse_banner(char *banner, atransport *t)
 {
-    char *type, *product, *end;
+    static const char *prop_seps = ";";
+    static const char key_val_sep = '=';
+    char *cp, *type;
 
     D("parse_banner: %s\n", banner);
     type = banner;
-    product = strchr(type, ':');
-    if(product) {
-        *product++ = 0;
-    } else {
-        product = "";
-    }
-
-        /* remove trailing ':' */
-    end = strchr(product, ':');
-    if(end) *end = 0;
-
-        /* save product name in device structure */
-    if (t->product == NULL) {
-        t->product = strdup(product);
-    } else if (strcmp(product, t->product) != 0) {
-        free(t->product);
-        t->product = strdup(product);
+    cp = strchr(type, ':');
+    if (cp) {
+        *cp++ = 0;
+        /* Nothing is done with second field. */
+        cp = strchr(cp, ':');
+        if (cp) {
+            char *save;
+            char *key;
+            key = strtok_r(cp + 1, prop_seps, &save);
+            while (key) {
+                cp = strchr(key, key_val_sep);
+                if (cp) {
+                    *cp++ = '\0';
+                    if (!strcmp(key, "ro.product.name"))
+                        qual_overwrite(&t->product, cp);
+                    else if (!strcmp(key, "ro.product.model"))
+                        qual_overwrite(&t->model, cp);
+                    else if (!strcmp(key, "ro.product.device"))
+                        qual_overwrite(&t->device, cp);
+                }
+                key = strtok_r(NULL, prop_seps, &save);
+            }
+        }
     }
 
     if(!strcmp(type, "bootloader")){

adb/adb.h

@@ -185,6 +185,8 @@ struct atransport
         /* used to identify transports for clients */
     char *serial;
     char *product;
+    char *model;
+    char *device;
     char *devpath;
     int adb_port; // Use for emulators (local transport)
 

adb/protocol.txt

@@ -72,7 +72,7 @@ large maxdata value, the connection with the other side must be closed.
 The system identity string should be "<systemtype>:<serialno>:<banner>"
 where systemtype is "bootloader", "device", or "host", serialno is some
 kind of unique ID (or empty), and banner is a human-readable version
-or identifier string (informational only).
+or identifier string.  The banner is used to transmit useful properties.
 
 
 --- OPEN(local-id, 0, "destination") -----------------------------------

adb/transport.c

@@ -601,6 +601,10 @@ static void transport_registration_func(int _fd, unsigned ev, void *data)
             free(t->product);
         if (t->serial)
             free(t->serial);
+        if (t->model)
+            free(t->model);
+        if (t->device)
+            free(t->device);
         if (t->devpath)
             free(t->devpath);