example client

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

1 files changed, 116 insertions, 0 deletions

diff --git a/example/client.c b/example/client.c
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+/* 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;
+}