Make udp sockets useful

Separate socket types: udp client and udp server
Allow client sockets to 'connect' to an address
Allow server sockets to 'bind' to an address
Add support for 'sendto' and 'recvfrom'
Add socket client and server examples
Document new udp sockets

Signed-off-by: Steve Bennett <steveb@workware.net.au>

1 files changed, 103 insertions, 19 deletions

diff --git a/jim-aio.c b/jim-aio.c
index b46019b..04af7e9 100644
--- a/jim-aio.c
+++ b/jim-aio.c
@@ -77,6 +77,7 @@ typedef struct AioFile {
 } AioFile;
 
 static int JimAioSubCmdProc(Jim_Interp *interp, int argc, Jim_Obj *const *argv);
+static int JimParseIpAddress(Jim_Interp *interp, const char *hostport, struct sockaddr_in *sa);
 
 static void JimAioSetError(Jim_Interp *interp, Jim_Obj *name)
 {
@@ -180,6 +181,44 @@ static int aio_cmd_read(Jim_Interp *interp, int argc, Jim_Obj *const *argv)
     return JIM_OK;
 }
 
+static int aio_cmd_recvfrom(Jim_Interp *interp, int argc, Jim_Obj *const *argv)
+{
+    AioFile *af = Jim_CmdPrivData(interp);
+    char *buf;
+    struct sockaddr_in sa;
+    long len;
+    socklen_t salen = sizeof(sa);
+    int rlen;
+
+    if (Jim_GetLong(interp, argv[0], &len) != JIM_OK) {
+        return JIM_ERR;
+    }
+
+    buf = Jim_Alloc(len + 1);
+
+    rlen = recvfrom(fileno(af->fp), buf, len, 0, (struct sockaddr *)&sa, &salen);
+    if (rlen < 0) {
+        Jim_Free(buf);
+        JimAioSetError(interp, NULL);
+        return JIM_ERR;
+    }
+    Jim_SetResult(interp, Jim_NewStringObjNoAlloc(interp, buf, rlen));
+
+    if (argc > 1) {
+        char buf[50];
+
+        inet_ntop(sa.sin_family, &sa.sin_addr, buf, sizeof(buf) - 7);
+        snprintf(buf + strlen(buf), 7, ":%d", ntohs(sa.sin_port));
+
+        if (Jim_SetVariable(interp, argv[1], Jim_NewStringObj(interp, buf, -1)) != JIM_OK) {
+            return JIM_ERR;
+        }
+    }
+
+    return JIM_OK;
+}
+
+
 static int aio_cmd_gets(Jim_Interp *interp, int argc, Jim_Obj *const *argv)
 {
     AioFile *af = Jim_CmdPrivData(interp);
@@ -264,6 +303,29 @@ static int aio_cmd_puts(Jim_Interp *interp, int argc, Jim_Obj *const *argv)
     return JIM_ERR;
 }
 
+static int aio_cmd_sendto(Jim_Interp *interp, int argc, Jim_Obj *const *argv)
+{
+    AioFile *af = Jim_CmdPrivData(interp);
+    int wlen;
+    int len;
+    const char *wdata;
+    struct sockaddr_in sa;
+
+    if (JimParseIpAddress(interp, Jim_GetString(argv[1], NULL), &sa) != JIM_OK) {
+        return JIM_ERR;
+    }
+    wdata = Jim_GetString(argv[0], &wlen);
+
+    /* Note that we don't validate the socket type. Rely on sendto() failing if appropriate */
+    len = sendto(fileno(af->fp), wdata, wlen, 0, (struct sockaddr*)&sa, sizeof(sa));
+    if (len < 0) {
+        JimAioSetError(interp, NULL);
+        return JIM_ERR;
+    }
+    Jim_SetResultInt(interp, len);
+    return JIM_OK;
+}
+
 static int aio_cmd_flush(Jim_Interp *interp, int argc, Jim_Obj *const *argv)
 {
     AioFile *af = Jim_CmdPrivData(interp);
@@ -492,6 +554,13 @@ static const jim_subcmd_type command_table[] = {
         .maxargs = 2,
         .description = "Read and return bytes from the stream. To eof if no len."
     },
+    {   .cmd = "recvfrom",
+        .args = "len ?addrvar?",
+        .function = aio_cmd_recvfrom,
+        .minargs = 1,
+        .maxargs = 2,
+        .description = "Receive up to 'len' bytes on the socket. Sets 'addrvar' with receive address, if set"
+    },
     {   .cmd = "gets",
         .args = "?var?",
         .function = aio_cmd_gets,
@@ -506,6 +575,13 @@ static const jim_subcmd_type command_table[] = {
         .maxargs = 2,
         .description = "Write the string, with newline unless -nonewline"
     },
+    {   .cmd = "sendto",
+        .args = "str address",
+        .function = aio_cmd_sendto,
+        .minargs = 2,
+        .maxargs = 2,
+        .description = "Send 'str' to the given address (dgram only)"
+    },
     {   .cmd = "flush",
         .function = aio_cmd_flush,
         .description = "Flush the stream"
@@ -723,6 +799,7 @@ static int JimAioSockCommand(Jim_Interp *interp, int argc,
         "unix", 
         "unix.server", 
         "dgram", 
+        "dgram.server", 
         "stream", 
         "stream.server",
         "pipe",
@@ -732,6 +809,7 @@ static int JimAioSockCommand(Jim_Interp *interp, int argc,
         SOCK_UNIX, 
         SOCK_UNIX_SERV, 
         SOCK_DGRAM_CL, 
+        SOCK_DGRAM_SERV, 
         SOCK_STREAM_CL, 
         SOCK_STREAM_SERV,
         SOCK_STREAM_PIPE,
@@ -753,25 +831,29 @@ wrongargs:
                     JIM_ERRMSG) != JIM_OK)
             return JIM_ERR;
 
-    if (socktype != SOCK_STREAM_PIPE) {
-        if (argc == 2) {
-            goto wrongargs;
-        }
+    if (argc == 3) {
         hostportarg = Jim_GetString(argv[2], NULL);
     }
+    else if (argc != 2 || (socktype != SOCK_STREAM_PIPE && socktype != SOCK_DGRAM_CL)) {
+        goto wrongargs;
+    }
 
     Jim_SetResultString(interp, "", 0);
 
+    hdlfmt = "aio.sock%ld" ;
+
     switch (socktype) {
     case SOCK_DGRAM_CL:
-        sock = socket(PF_INET,SOCK_DGRAM,0);
-        if (sock < 0) {
-            JimAioSetError(interp, NULL);
-            return JIM_ERR;
+        if (argc == 2) {
+            /* No address, so an unconnected dgram socket */
+            sock = socket(PF_INET,SOCK_DGRAM,0);
+            if (sock < 0) {
+                JimAioSetError(interp, NULL);
+                return JIM_ERR;
+            }
+            break;
         }
-        hdlfmt = "aio.sockdgram%ld" ;
-        break;
-
+        /* fall through */
     case SOCK_STREAM_CL:    
         {
             struct sockaddr_in sa;
@@ -779,7 +861,7 @@ wrongargs:
             if (JimParseIpAddress(interp, hostportarg, &sa) != JIM_OK) {
                 return JIM_ERR;
             }
-            sock = socket(PF_INET,SOCK_STREAM,0);
+            sock = socket(PF_INET,socktype == SOCK_DGRAM_CL ? SOCK_DGRAM : SOCK_STREAM,0);
             if (sock < 0) {
                 JimAioSetError(interp, NULL);
                 return JIM_ERR;
@@ -790,11 +872,11 @@ wrongargs:
                 close(sock);
                 return JIM_ERR;
             }
-            hdlfmt = "aio.sockstream%ld" ;
         }
         break;
 
     case SOCK_STREAM_SERV: 
+    case SOCK_DGRAM_SERV: 
         {
             struct sockaddr_in sa;
 
@@ -802,7 +884,7 @@ wrongargs:
                 JimAioSetError(interp, argv[2]);
                 return JIM_ERR;
             }
-            sock = socket(PF_INET,SOCK_STREAM,0);
+            sock = socket(PF_INET,socktype == SOCK_DGRAM_SERV ? SOCK_DGRAM : SOCK_STREAM,0);
             if (sock < 0) {
                 JimAioSetError(interp, NULL);
                 return JIM_ERR;
@@ -817,11 +899,13 @@ wrongargs:
                 close(sock);
                 return JIM_ERR;
             }
-            res = listen(sock,5);   
-            if (res) {
-                JimAioSetError(interp, NULL);
-                close(sock);
-                return JIM_ERR;
+            if (socktype != SOCK_DGRAM_SERV) {
+                res = listen(sock,5);   
+                if (res) {
+                    JimAioSetError(interp, NULL);
+                    close(sock);
+                    return JIM_ERR;
+                }
             }
             hdlfmt = "aio.socksrv%ld" ;
         }