initial import

1 files changed, 277 insertions, 0 deletions

diff --git a/sock_stuff.c b/sock_stuff.c
new file mode 100644
index 0000000..1a23bc1
--- /dev/null
+++ b/sock_stuff.c
@@ -0,0 +1,277 @@
+#include <stdio.h>
+#include <stddef.h>
+#include <unistd.h>
+#include <errno.h>
+#include <sys/time.h>
+#include <sys/stat.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <netinet/in.h>
+#include <netdb.h>
+#include <arpa/inet.h>
+#include "sock_stuff.h"
+
+#define RECV_TIMEOUT 10000
+
+int create_unix_socket (const char *filename)
+{
+    struct sockaddr_un name;
+    int sock;
+    size_t size;
+
+    // remove if still present
+    unlink(filename);
+
+    /* Create the socket. */
+    sock = socket (PF_LOCAL, SOCK_STREAM, 0);
+    if (sock < 0) {
+	perror ("socket");
+	return -1;
+    }
+
+    /* Bind a name to the socket. */
+    name.sun_family = AF_LOCAL;
+    strncpy (name.sun_path, filename, sizeof (name.sun_path));
+    name.sun_path[sizeof (name.sun_path) - 1] = '\0';
+
+    /* The size of the address is
+       the offset of the start of the filename,
+       plus its length,
+       plus one for the terminating null byte.
+       Alternatively you can just do:
+       size = SUN_LEN (&name);
+     */
+    size = (offsetof (struct sockaddr_un, sun_path)
+	    + strlen (name.sun_path) + 1);
+
+    if (bind (sock, (struct sockaddr *) &name, size) < 0) {
+	perror("bind");
+	close(sock);
+	return -1;
+    }
+
+    if (listen(sock, 10) < 0) {
+	perror("listen");
+	close(sock);
+	return -1;
+    }
+
+    return sock;
+}
+
+int connect_unix_socket(const char *filename)
+{
+    struct sockaddr_un name;
+    int sfd = -1;
+    size_t size;
+    struct stat fst;
+
+    // check if socket file exists...
+    if (stat(filename, &fst) != 0) {
+	fprintf(stderr, "%s: stat '%s': %s\n", __func__, filename, strerror(errno));
+	return -1;
+    }
+
+    // ... and if it is a unix domain socket
+    if (!S_ISSOCK(fst.st_mode)) {
+	fprintf(stderr, "%s: File '%s' is not a socket!\n", __func__, filename);
+	return -1;
+    }
+
+    // make a new socket
+    if ((sfd = socket(PF_LOCAL, SOCK_STREAM, 0)) < 0) {
+	fprintf(stderr, "%s: socket: %s\n", __func__, strerror(errno));
+	return -1;
+    }
+
+    // and connect to 'filename'
+    name.sun_family = AF_LOCAL;
+    strncpy(name.sun_path, filename, sizeof(name.sun_path));
+    name.sun_path[sizeof(name.sun_path) - 1] = 0;
+
+    size = (offsetof (struct sockaddr_un, sun_path)
+	    + strlen (name.sun_path) + 1);
+
+    if (connect(sfd, (struct sockaddr*)&name, size) < 0) {
+	close(sfd);
+	fprintf(stderr, "%s: connect: %s\n", __func__, strerror(errno));
+	return -1;
+    }
+
+    return sfd;
+}
+
+int create_socket(uint16_t port)
+{
+    int sfd = -1;
+    int yes = 1;
+    struct sockaddr_in saddr;
+
+    if ( 0 > ( sfd = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP) ) ) {
+	perror("socket()");
+	return -1;
+    }
+
+    if (setsockopt(sfd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(int)) == -1) {
+	perror("setsockopt()");
+	close(sfd);
+	return -1;
+    }
+
+    memset((void *)&saddr, 0, sizeof(saddr));
+    saddr.sin_family = AF_INET;
+    saddr.sin_addr.s_addr = htonl(INADDR_ANY);
+    saddr.sin_port = htons(port);
+
+    if(0 > bind(sfd, (struct sockaddr *)&saddr , sizeof(saddr))) {
+	perror("bind()");
+	close(sfd);
+	return -1;
+    }
+		   
+    if (listen(sfd, 1) == -1) {
+	perror("listen()");
+	close(sfd);
+	return -1;
+    }
+
+    return sfd;    
+}
+
+int connect_socket(const char *addr, uint16_t port)
+{
+    int sfd = -1;
+    int yes = 1;
+    struct hostent *hp;
+    struct sockaddr_in saddr;
+
+    if (!addr) {
+	errno = EINVAL;
+	return -1;
+    }
+
+    if ((hp = gethostbyname(addr)) == NULL) {
+	fprintf(stderr, "%s: unknown host '%s'\n", __func__, addr);
+	return -1;
+    }
+
+    if (!hp->h_addr) {
+	fprintf(stderr, "%s: gethostbyname returned NULL address!\n", __func__);
+	return -1;
+    }
+
+    if ( 0 > ( sfd = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP) ) ) {
+	perror("socket()");
+	return -1;
+    }
+
+    if (setsockopt(sfd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(int)) == -1) {
+	perror("setsockopt()");
+	close(sfd);
+	return -1;
+    }
+
+    memset((void *)&saddr, 0, sizeof(saddr));
+    saddr.sin_family = AF_INET;
+    saddr.sin_addr.s_addr = (uint32_t)hp->h_addr;
+    saddr.sin_port = htons(port);
+
+    if (connect(sfd, (struct sockaddr*)&saddr, sizeof(saddr)) < 0) {
+	perror("connect");
+	close(sfd);
+	return -2;
+    }
+
+    return sfd;
+}
+
+int check_fd(int fd, fd_mode fdm, unsigned int timeout)
+{
+    fd_set fds;
+    int sret;
+    int eagain;
+    struct timeval to;
+
+    if (fd <= 0) {
+	fprintf(stderr, "ERROR: invalid fd in check_fd %d\n", fd);
+	return -1;
+    }
+
+    FD_ZERO(&fds);
+    FD_SET(fd, &fds);
+
+    to.tv_sec = (time_t)(timeout/1000);
+    to.tv_usec = (time_t)((timeout-(to.tv_sec*1000))*1000);
+
+    sret = -1;
+
+    do {
+	eagain = 0;
+	switch(fdm) {
+	    case fdread:
+		sret = select(fd+1,&fds,NULL,NULL,&to);
+                break;
+            case fdwrite:
+                sret = select(fd+1,NULL,&fds,NULL,&to);
+                break;
+            case fdexcept:
+                sret = select(fd+1,NULL,NULL,&fds,&to);
+                break;
+	}
+	
+	if (sret < 0) {
+	    switch(errno) {
+		case EINTR:
+		    // interrupt signal in select
+		    fprintf(stderr, "%s: EINTR\n", __func__);
+		    eagain = 1;
+		    break;
+		case EAGAIN:
+		    fprintf(stderr, "%s: EAGAIN\n", __func__);
+		    break;
+		default:
+		    fprintf(stderr, "%s: select failed: %s\n", __func__, strerror(errno));
+		    return -1;
+	    }
+	}
+    } while (eagain);
+
+    return sret;
+}
+
+int recv_buf(int fd, void *data, size_t length)
+{
+    return recv_buf_timeout(fd, data, length, 0, RECV_TIMEOUT);
+}
+
+int peek_buf(int fd, void *data, size_t length)
+{
+    return recv_buf_timeout(fd, data, length, MSG_PEEK, RECV_TIMEOUT);
+}
+
+int recv_buf_timeout(int fd, void *data, size_t length, int flags, unsigned int timeout)
+{
+    int res;
+    int result;
+
+    // check if data is available
+    res = check_fd(fd, fdread, timeout);
+    if (res <= 0) {
+	return res;
+    }
+
+    // if we get here, there _is_ data available
+    result = recv(fd, data, length, flags);
+    if (res > 0 && result == 0) {
+	// but this is an error condition
+	fprintf(stderr, "%s: fd=%d\n", __func__, fd);
+	return -1;
+    }
+    return result;
+}
+
+int send_buf(int fd, void *data, size_t length)
+{
+    return send(fd, data, length, 0);
+}
+