example client

git-svn-id: https://svn.kapsi.fi/jpa/nanopb@958 e3a754e5-d11d-0410-8d38-ebb782a927b9

example/Makefile

@@ -1,10 +1,10 @@
 CFLAGS=-ansi -Wall -Werror -I .. -g -O0
 DEPS=../pb_decode.c ../pb_decode.h ../pb_encode.c ../pb_encode.h ../pb.h
 
-all: server
+all: server client
 
 %: %.c $(DEPS) fileproto.h
-	$(CC) $(CFLAGS) -o $@ $< ../pb_decode.c ../pb_encode.c fileproto.c
+	$(CC) $(CFLAGS) -o $@ $< ../pb_decode.c ../pb_encode.c fileproto.c common.c
 
 fileproto.h: fileproto.proto ../generator/nanopb_generator.py
 	protoc -I. -I../generator -I/usr/include -ofileproto.pb $<

example/client.c

@@ -0,0 +1,116 @@
+/* This is a simple TCP client that connects to port 1234 and prints a list
+ * of files in a given directory.
+ *
+ * It directly deserializes and serializes messages from network, minimizing
+ * memory use.
+ * 
+ * For flexibility, this example is implemented using posix api.
+ * In a real embedded system you would typically use some other kind of
+ * a communication and filesystem layer.
+ */
+
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <netinet/in.h>
+#include <unistd.h>
+#include <dirent.h>
+#include <stdio.h>
+#include <string.h>
+
+#include <pb_encode.h>
+#include <pb_decode.h>
+
+#include "fileproto.h"
+#include "common.h"
+
+bool printfile_callback(pb_istream_t *stream, const pb_field_t *field, void *arg)
+{
+    FileInfo fileinfo;
+    
+    if (!pb_decode(stream, FileInfo_fields, &fileinfo))
+        return false;
+    
+    printf("%-10lld %s\n", fileinfo.inode, fileinfo.name);
+    
+    return true;
+}
+
+bool listdir(int fd, char *path)
+{
+    ListFilesRequest request;
+    ListFilesResponse response;
+    pb_istream_t input = pb_istream_from_socket(fd);
+    pb_ostream_t output = pb_ostream_from_socket(fd);
+    uint8_t zero = 0;
+    
+    if (path == NULL)
+    {
+        request.has_path = false;
+    }
+    else
+    {
+        request.has_path = true;
+        if (strlen(path) + 1 > sizeof(request.path))
+        {
+            fprintf(stderr, "Too long path.\n");
+            return false;
+        }
+        
+        strcpy(request.path, path);
+    }
+    
+    if (!pb_encode(&output, ListFilesRequest_fields, &request))
+    {
+        fprintf(stderr, "Encoding failed.\n");
+        return false;
+    }
+    
+    /* We signal the end of request with a 0 tag. */
+    pb_write(&output, &zero, 1);
+    
+    response.file.funcs.decode = &printfile_callback;
+    
+    if (!pb_decode(&input, ListFilesResponse_fields, &response))
+    {
+        fprintf(stderr, "Decoding failed.\n");
+        return false;
+    }
+    
+    if (response.path_error)
+    {
+        fprintf(stderr, "Server reported error.\n");
+        return false;
+    }
+    
+    return true;
+}
+
+int main(int argc, char **argv)
+{
+    int sockfd;
+    struct sockaddr_in servaddr;
+    char *path = NULL;
+    
+    if (argc > 1)
+        path = argv[1];
+    
+    sockfd = socket(AF_INET, SOCK_STREAM, 0);
+    
+    memset(&servaddr, 0, sizeof(servaddr));
+    servaddr.sin_family = AF_INET;
+    servaddr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
+    servaddr.sin_port = htons(1234);
+    
+    if (connect(sockfd, (struct sockaddr *)&servaddr, sizeof(servaddr)) != 0)
+    {
+        perror("connect");
+        return 1;
+    }
+    
+    if (!listdir(sockfd, path))
+        return 2;
+    
+    close(sockfd);
+    
+    return 0;
+}

example/common.c

@@ -0,0 +1,49 @@
+/* Simple binding of nanopb streams to TCP sockets.
+ */
+
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <pb_encode.h>
+#include <pb_decode.h>
+
+#include "common.h"
+
+static bool write_callback(pb_ostream_t *stream, const uint8_t *buf, size_t count)
+{
+    int fd = (int)stream->state;
+    return send(fd, buf, count, 0) == count;
+}
+
+static bool read_callback(pb_istream_t *stream, uint8_t *buf, size_t count)
+{
+    int fd = (int)stream->state;
+    int result;
+    
+    if (buf == NULL)
+    {
+        /* Well, this is a really inefficient way to skip input. */
+        /* It is only used when there are unknown fields. */
+        char dummy;
+        while (count-- && recv(fd, &dummy, 1, 0) == 1);
+        return count == 0;
+    }
+    
+    result = recv(fd, buf, count, MSG_WAITALL);
+    
+    if (result == 0)
+        stream->bytes_left = 0; /* EOF */
+    
+    return result == count;
+}
+
+pb_ostream_t pb_ostream_from_socket(int fd)
+{
+    pb_ostream_t stream = {&write_callback, (void*)fd, SIZE_MAX, 0};
+    return stream;
+}
+
+pb_istream_t pb_istream_from_socket(int fd)
+{
+    pb_istream_t stream = {&read_callback, (void*)fd, SIZE_MAX};
+    return stream;
+}

example/common.h

@@ -0,0 +1,9 @@
+#ifndef _PB_EXAMPLE_COMMON_H_
+#define _PB_EXAMPLE_COMMON_H_
+
+#include <pb.h>
+
+pb_ostream_t pb_ostream_from_socket(int fd);
+pb_istream_t pb_istream_from_socket(int fd);
+
+#endif

example/server.c

@@ -21,28 +21,7 @@
 #include <pb_decode.h>
 
 #include "fileproto.h"
-
-bool write_callback(pb_ostream_t *stream, const uint8_t *buf, size_t count)
-{
-    int fd = *(int*)stream->state;
-    return send(fd, buf, count, 0) == count;
-}
-
-bool read_callback(pb_istream_t *stream, uint8_t *buf, size_t count)
-{
-    int fd = *(int*)stream->state;
-    
-    if (buf == NULL)
-    {
-        /* Well, this is a really inefficient way to skip input. */
-        /* It is only used when there are unknown fields. */
-        char dummy;
-        while (count-- && recv(fd, &dummy, 1, 0) == 1);
-        return count == 0;
-    }
-    
-    return recv(fd, buf, count, MSG_WAITALL) == count;
-}
+#include "common.h"
 
 bool listdir_callback(pb_ostream_t *stream, const pb_field_t *field, const void *arg)
 {
@@ -70,8 +49,8 @@ void handle_connection(int connfd)
 {
     ListFilesRequest request;
     ListFilesResponse response;
-    pb_istream_t input = {&read_callback, &connfd, SIZE_MAX};
-    pb_ostream_t output = {&write_callback, &connfd, SIZE_MAX, 0};
+    pb_istream_t input = pb_istream_from_socket(connfd);
+    pb_ostream_t output = pb_ostream_from_socket(connfd);
     DIR *directory;
     
     if (!pb_decode(&input, ListFilesRequest_fields, &request))
@@ -109,9 +88,12 @@ int main(int argc, char **argv)
 {
     int listenfd, connfd;
     struct sockaddr_in servaddr;
+    int reuse = 1;
     
     listenfd = socket(AF_INET, SOCK_STREAM, 0);
     
+    setsockopt(listenfd, SOL_SOCKET, SO_REUSEADDR, &reuse, sizeof(reuse));
+    
     memset(&servaddr, 0, sizeof(servaddr));
     servaddr.sin_family = AF_INET;
     servaddr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);