Updated docs and started on client.

1 files changed, 415 insertions, 0 deletions

diff --git a/client/nft.c b/client/nft.c
new file mode 100644
index 0000000..9d03295
--- /dev/null
+++ b/client/nft.c
@@ -0,0 +1,415 @@
+/*  Next File Transfer Client
+    Copyright (C) 2020  Ian Cowburn
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+*/
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netinet/tcp.h>
+#include <netdb.h>
+
+static const char *name;
+
+
+static void *Malloc(size_t len)
+{
+    void *p;
+
+    p = malloc(len);
+
+    if (!p)
+    {
+    	perror(name);
+	exit(EXIT_FAILURE);
+    }
+
+    return p;
+}
+
+
+static char *GetLine(char *buff, size_t len)
+{
+    size_t l;
+
+    if (feof(stdin))
+    {
+	return NULL;
+    }
+
+    printf("NFT> ");
+
+    if (!fgets(buff, len, stdin))
+    {
+	return NULL;
+    }
+
+    l = strlen(buff);
+
+    if (l > 0 && buff[l-1]=='\n')
+    {
+	buff[l-1]=0;
+    }
+
+    if (l)
+    {
+	return buff;
+    }
+    else
+    {
+	return GetLine(buff, len);
+    }
+}
+
+
+static int Connect(const char *n, int p)
+{
+    struct hostent *remote;
+    struct sockaddr_in addr;
+    int sock;
+
+    if (!(remote = gethostbyname(n)))
+    {
+	fprintf(stderr,"%s: unknown host %s\n",name,n);
+	exit(EXIT_FAILURE);
+    }
+
+    memcpy(&addr.sin_addr, remote->h_addr, remote->h_length);
+
+    if ((sock = socket(AF_INET, SOCK_STREAM, 0))==-1)
+    {
+	perror(name);
+	exit(EXIT_FAILURE);
+    }
+
+    addr.sin_family = AF_INET;
+    addr.sin_port = htons(p);
+
+    if (connect(sock,(void*)&addr,sizeof(addr)) == -1)
+    {
+	perror(name);
+	exit(EXIT_FAILURE);
+    }
+
+    return sock;
+}
+
+
+static int Read(int sock, char *buff, size_t len)
+{
+    while(len > 0)
+    {
+	size_t rd;
+
+	rd = read(sock, buff, len);
+
+	if (rd == -1)
+	{
+	    perror(name);
+	    return 0;
+	}
+	else if (rd == 0)
+	{
+	    return 0;
+	}
+	else
+	{
+	    len -= rd;
+	    buff += rd;
+	}
+    }
+
+    return 1;
+}
+
+
+static int Write(int sock, const char *buff, size_t len)
+{
+    while(len > 0)
+    {
+	size_t wr;
+
+	wr = write(sock, buff, len);
+
+	if (wr == -1)
+	{
+	    perror(name);
+	    return 0;
+	}
+	else if (wr == 0)
+	{
+	    return 0;
+	}
+	else
+	{
+	    len -= wr;
+	    buff += wr;
+	}
+    }
+
+    return 1;
+}
+
+
+static int WriteBlock(int sock, const char *block, size_t len)
+{
+    char buff[32];
+
+    if (len > 99999)
+    {
+    	fprintf(stderr, "%s: length of block %zu too large\n", name, len);
+	return 0;
+    }
+
+    snprintf(buff, sizeof buff, "%.5zu", len); 
+
+    if (!Write(sock, buff, 5))
+    {
+    	return 0;
+    }
+
+    if (!Write(sock, block, len))
+    {
+    	return 0;
+    }
+
+    return 1;
+}
+
+
+static size_t ReadSize(int sock)
+{
+    char buff[32];
+
+    if (!Read(sock, buff, 5))
+    {
+    	return 0;
+    }
+
+    return atoi(buff);
+}
+
+
+static size_t FileSize(const char *path)
+{
+    struct stat st;
+
+    if (stat(path, &st) == 0)
+    {
+    	return st.st_size;
+    }
+    else
+    {
+    	return 0;
+    }
+}
+
+
+static int Put(int sock, const char *path)
+{
+    int quit = 0;
+    char status[3] = {0};
+    size_t len;
+    int fd;
+
+    if ((len = FileSize(path)) == 0)
+    {
+    	perror(path);
+    }
+    else
+    {
+	char *buff;
+	int fd;
+
+	buff = Malloc(len);
+
+	fd = open(path, O_RDONLY);
+	read(fd, buff, len);
+	close(fd);
+
+	if (!Write(sock, "PF", 2))
+	{
+	    quit = 1;
+	}
+
+	if (!quit && !WriteBlock(sock, path, strlen(path)))
+	{
+	    quit = 1;
+	}
+
+	if (!quit && !WriteBlock(sock, buff, len))
+	{
+	    quit = 1;
+	}
+
+	if (!quit && Read(sock, status, 2))
+	{
+	    if (strcmp(status, "!E") == 0)
+	    {
+		printf("Command failed\n");
+	    }
+	}
+	else
+	{
+	    quit = 1;
+	}
+
+    }
+
+    return quit;
+}
+
+
+static int Get(int sock, const char *path)
+{
+    int quit = 0;
+    char status[3] = {0};
+    int fd;
+
+    if ((fd = open(path, O_WRONLY|O_CREAT|O_TRUNC)) == -1)
+    {
+    	perror(path);
+	return 0;
+    }
+
+    if (!Write(sock, "GF", 2))
+    {
+	quit = 1;
+    }
+
+    if (!quit && !WriteBlock(sock, path, strlen(path)))
+    {
+	quit = 1;
+    }
+
+    if (!quit && Read(sock, status, 2))
+    {
+	if (strcmp(status, "!E") == 0)
+	{
+	    printf("Command failed\n");
+	}
+    	else
+	{
+	    size_t len;
+
+	    if ((len = ReadSize(sock)) > 0)
+	    {
+		char buff[100000];
+
+		if (Read(sock, buff, len))
+		{
+		    write(fd, buff, len);
+		}
+		else
+		{
+		    quit = 1;
+		}
+	    }
+	}
+    }
+    else
+    {
+	quit = 1;
+    }
+
+    close(fd);
+
+    return quit;
+}
+
+
+static int Cd(int sock, const char *path)
+{
+    int quit = 0;
+
+    return quit;
+}
+
+
+static int Mkdir(int sock, const char *path)
+{
+    int quit = 0;
+
+    return quit;
+}
+
+
+int main(int argc, char *argv[])
+{
+    char buff[1024];
+    int sock;
+    int quit = 0;
+
+    if ((name = strrchr(argv[0], '/')))
+    {
+    	name++;
+    }
+    else
+    {
+    	name = argv[0];
+    }
+
+    if (argc<3)
+    {
+	fprintf(stderr,"%s: usage %s host port\n",name,name);
+	exit(EXIT_FAILURE);
+    }
+
+    sock = Connect(argv[1],atoi(argv[2]));
+
+    while(!quit && GetLine(buff, sizeof buff))
+    {
+    	char *tok;
+
+	tok = strtok(buff, " \t");
+
+	if (strcmp(tok, "exit") == 0)
+	{
+	    break;
+	}
+	else if (strcmp(tok, "put") == 0)
+	{
+	    quit = Put(sock, strtok(NULL, " \t"));
+	}
+	else if (strcmp(tok, "get") == 0)
+	{
+	    quit = Get(sock, strtok(NULL, " \t"));
+	}
+	else if (strcmp(tok, "cd") == 0)
+	{
+	    quit = Cd(sock, strtok(NULL, " \t"));
+	}
+	else if (strcmp(tok, "mkdir") == 0)
+	{
+	    quit = Mkdir(sock, strtok(NULL, " \t"));
+	}
+	else
+	{
+	    printf("Unrecognised command '%s'\n", tok);
+	}
+    }
+
+    close(sock);
+
+    return EXIT_SUCCESS;
+}